go to link The presence of lithiasis and of obstructive uropathy signs were determined. The plain film was only used as a guide for the US exam. Clinical follow-up of all patients was obtained. Ureteral lithiasis was confirmed in 56 patients. The 11 lithiasis not detected by US were passed spontaneously 10 were CT with a lower sensitivity and radiation dose that has a good practical value. Imaging diagnostics of the wrist: For tears of the triangular fibrocartilage, arthrography, arthro- CT , and MRI demonstrated a sensitivity and specificity of more than 0.
Ulno-lunate and ulno-triquetral ligament defects were demonstrated more exactly by arthrography. Insgesamt Untersuchungen des Handgelenkes wurden fuer einen dreijaehrigen Beobachtungszeitraum retrospektiv ausgewertet. Lediglich der positive Vorhersagewert differierte, allerdings nicht. MR-urography and CT -urography: Klinik fuer Radiologische Diagnostik. Die Kombination mit niedrigdosiertem Furosemid mg i. In those patients with established carcinoma, a CT examination was also performed.
SE sequences with long echo times detected prostatitis, adenoma and carcinoma of the prostate with a high degree of sensitivity. However, at present, differentiation between adenoma, prostatis and carcinoma is not possible with sufficient accuracy. Reliable diagnosis of a prostate carcinoma still requires a biopsy.
Because of the high soft tissue contrast and the possibility of selecting any orientation for the plane under investigation, however, MRI represents an improvement in the preoperative diagnosis of local spread. Sonography findings in tears of the extensor pollicis longus tendon and correlation with CT , MRI and surgical findings.
We present our experience in the diagnosis of extensor pollicis longus tendon tears using different imaging methods. In the past 2 years, 12 patients 7 males, 5 females with extension deficit of distal phalanx of thumb were diagnosed with extensor pollicis longus tendon EPL rupture by means of different imaging methods. The ultrasound pattern consisted of a gap between tendon stumps occupied by a continuous eight cases or discontinuous four cases attenuated hypoechoic string.
In nine cases, the tendon ends were identified as a thickened stump-like structure. In the other three cases, tendon stumps were attenuated and mixed with atrophic muscle or wrist subcutaneous fat. Optimierung der Aufnahme- und Rekonstruktionsparameter. Goettingen Germany ; Merten, H.
To determine the optimal scan parameters in multislice helical CT MSCT of the facial bone complex for both axial scanning and multiplanar reconstructions. An anthropomorphic skull phantom was examined with a MSCT. Axial scans were performed with continuously increasing collimations 4 x 1. Multiplanar reconstructions in coronal and parasagittal planes with different reconstruction increment and slice thickness were evaluated in terms of image noise, contour artifacts and visualisation of anatomical structures.
The best image quality was obtained with a collimation of 4 x 1. A reconstruction increment of 0. With these parameters the bone structures were depicted in an optimal way without artifacts. The tube current could be reduced to 50 mA without significant loss of image quality. Low-dose MSCT using thin collimation, low table speed and small reconstruction increments provides excellent data for both axial images and multiplanar reconstructions in patients with facial trauma.
An additional examination in coronal orientation is therefore no longer necessary. Ein anthropomorphes Schaedel-Phantom wurde in axialer Schichtfuehrung mit einem MSCT untersucht, wobei die Kollimation 1,25 - 2,5 mm , der Tischvorschubfaktor Pitch 3 - 6 und der Roehrenstrom 20 - mA systematisch variiert wurden. Aus den Volumendatensaetzen wurden jeweils koronare und parasagittale Sekundaerreformationen mit unterschiedlichen.
CT and MRI in progressive multifocal leukoencephalopathy. Germany ; Heindel, W. Germany ; Schroeder, R.
Germany ; Lackner, K. Radiological findings and course of progressive multifocal leukoencephalopathy in 14 patients 1 woman, 13 men; 13 HIV seropositive, 1 chronic lymphatic leukaemia were analysed retrospectively and correlated with clinical symptoms. CT scans and MR images of 9 patients, which had been obtained in less than two weeks, could be compared to each other.
MRI was superior to CT: Cortical involvement, mass effect or signs of atrophy were missing. Only 1 of 65 lesions showed a tiny enhancement after Gd injection. Due to the pattern and spread of lesions, which showed a close correlation to the neurologic symptoms, three different types of PML are suggested: Indikationen beim differenzierten Schilddruesenkarzinom und bei Lebertumoren.
Die diagnostische Genauigkeit dieser szintigraphischen Methode ist jedoch aufgrund limitierter raeumlicher Aufloesung begrenzt. Auch hier limitiert die begrenzte morphologische Information der Szintigraphie das Therapiemonitoring. Chronic inflammatory arthritis is recognized specifically by bone erosions, caused by characteristic pannus tissue.
In the finger joints dynamic low-Tesla MRI is nearly double but not completely sensitive in the detection of erosions than conventional radiography, sonography takes an intermediate position. Less specific signs of synovitis and tenosynovitis are shown with high sensitivity by both 3 2 -phase bone scintigraphy and ultrasound, MRI is less sensitive in this respect.
However, standard situation of inflammation in bone scintigraphy - positive finding in early as well as late phase - is of surprisingly low sensitivity, any singular finding in the early or late phase has to be regarded as positive. Specificity of these singular findings is nevertheless sufficiently high, acute inflammatory joint changes and even erosions are also seen with MRI in obviously healthy persons. Only 2-phase bone scintigraphy is easily able to present a simultaneous survey of all joints of the body.
For this reason 2-phase bone scintigraphy is most suitable for exclusion but also for primary diagnosis of disease, specification must be done afterwards by other imaging modalities or by laboratory findings. For the first time, computed tomography was performed for further investigation of midface hypoplasia. The early diagnosis of SWS could be made by correlation of the radiological and clinical findings.
For evaluation of progression, follow-up radiological examinations of the skeleton were performed in four children surviving infancy. Skeletal radiographs revealed bowing of the long tubular bones, most pronounced at the lower extremities.
Additional findings were internal triangular cortical diaphyseal thickening at the concave side of the bowing, wide metaphyses with abnormal trabecular pattern and radiolucencies. Four patients survived infancy. Clinically, they suffered from recurrent aspiration pneumonia and recurrent episodes of hyperthermia as well as form cutaneous and mucosal infections.
The follow-up radiographs showed progressive bowing of the long tubular bones as well as progressive metaphyseal decalcification. However, a close cooperation between radiologists, clinicians, and geneticists is required for correlation of clinical and radiological findings. The few cases that survive infancy have progressing orthopaedic problems. Die typischen radiologischen und CT -Befunde beim kongenitalen Stueve. Dual phase helical CT versus portal venous phase CT for the detection of colorectal liver metastases: Correlation with intra-operative sonography , surgical and pathological findings.
To assess whether dual phase helical computed tomography DPCT of the liver improves the detection of colorectal liver metastases compared with portal venous phase PVP imaging alone. DPCT was performed in 33 consecutive patients before laparotomy for resection of colorectal liver metastases. CT comprised 8-mm slice collimation with a pitch of 1 to 1. Alternative-free response receiver operating characteristic AFROC methodology was used to analyse the results, which were correlated with surgery, intra-operative ultrasound and histology. The mean observer sensitivities for malignant lesion detection were There was a statistically significant improvement in malignant lesion detection using DPCT when compared with PVP imaging alone P Clinical neuroanatomy and diagnostic imaging and evaluation of the brain.
MRI and CT atlas. Atlas der Magnetresonanztomographie und Computertomographie. New features of this 3rd German edition are: Ihre Anzahl wurde nahezu verdoppelt. In den nun grossen Abbildungen konnte die Zahl der bezeichneten Hirnstrukturen wesentlich erhoeht werden. Neues Wissen wurde in den Text und in die Abbildungen aufgenommen.
Trotz bestehender Vorteile hat die Bildfusion bisher nur in einzelnen Zentren Einzug in die nuklearmedizinische und radiologische Routinediagnostik gefunden. Um die Bildfusion allgemein einsetzen zu koennen, sind bestimmte technische und logistische Voraussetzungen notwendig. Dies betrifft die Langzeitarchivierung von diagitalen Daten, die Moeglichkeiten zur Datenuebertragung und die Weiterentwicklung der verfuegbaren Software, auch was den Bedienkomfort und die Dokumentation anbelangt. Zudem ist es notwendig, die Exaktheit der Koregistrierung und damit die Qualitaet der Bildfusion durch kontrollierte Studien zu validieren.
Early clinical phase of patient's management after polytrauma using 1- and 4-slice helical CT ; Fruehes klinisches Management nach Polytrauma mit 1- und 4-Schicht-Spiral- CT. In the early clinical phase the comprehensive imaging of patients with multiple trauma using helical CT is already established. Aim of this study was to assess whether MSCT may improve the patient management and the diagnostic results. The procedure is designed as follows: Then the patient is moved to CT.
After CT selected radiograms of the extremities were taken. Excluding 1 case death during 1-sl. The change from 1slice-helical CT to 4 slice-helical CT allowed us to reduce the stay in the CT room from 28 to 16 min. Advantages for the patient arose from the standardized examination protocol using multislice CT. If integrated in an interdisciplinary management concept, it is a good compromise between examination time, comprehensive diagnostic imaging, life-saving therapeutic procedures, and therapy planning.
Klinisch ausgewaehlte Extremitaetenaufnahmen wurden ergaenzt. Mediastinal fibrosis with pulmonary artery obstruction; diagnosis and investigation with helical CT imaging including 3-dimensional reconstructions; Pulomonalarterienstenose bei aggresiver Mediastinalfibrose; Diagnostik und 3D-Darstellung mittels helikaler CT -Untersuchung. An aggressive mediastinal fibrosis was found in a year-old female, suffering from dysphagia, stabbing pain in the chest, and an unclear weight loss.
In this case, the rare combination of esophageal involvement, bronchial narrowing, and pulmonary artery obstruction could easily be demonstrated with a barium study and a helical CT examination including three-dimensional reconstructions. Mittels klinischer und radiologischer Abklaerung konnte eine aggressive Mediastinalfibrose diagnostiziert werden. Die seltene Kombination einer Oesophaguseinengung mit Pulmonalarterienstenosen sowie einer Bronchuskompression konnte nichtinvasiv mittels Oesophagogramm und helikaler CT -Untersuchung zuverlaessig und schnell dargestellt werden.
Several radiologic features such as hematoma volume are related to poor outcome following an intracerebral hemorrhage and can be measured with transcranial duplex sonography. We sought to determine the prognostic value of transcranial duplex sonography in patients with intracerebral hemorrhage. We conducted a prospective study of patients diagnosed with spontaneous intracerebral hemorrhage.
Transcranial duplex sonography examinations were performed within 2 hours of baseline CT , and we recorded the following variables: We correlated these data with the CT scans and assessed the prognostic value of the transcranial duplex sonography measurements. We assessed early neurologic deterioration during hospitalization and mortality at 1-month follow-up. We included 35 patients with a mean age of Median baseline hematoma volume was 9. A second regression analysis with CT variables also demonstrated that hematoma volume was associated with early neurologic deterioration and mortality.
When we compared the rating operation curves of both models, their predictive power was similar. Transcranial duplex sonography showed an excellent correlation with CT in assessing hematoma volume and midline shift in patients with intracerebral hemorrhage. Hematoma volume measured with transcranial duplex sonography was an independent predictor of poor outcome. New possibilities in the diagnosis of ischemia.
Coronary CT -angiography CCTA plays an increasing role in the primary diagnostics of coronary artery disease CAD according to the present guidelines but also in clinical reality. The sensitivity and negative predictive value of CCTA is very high, but the specificity could still be improved.
CT urography in women with primary or recurrent pelvic tumors. Background and initial experiences; CT -Urographie bei Frauen mit primaeren oder rezidivierenden Beckentumoren. Hintergrund und erste Erfahrungen. German guidelines advocate diagnostic imaging for local recurrence and metastasis while there are no recommendations for primary tumors. As excretory urography has been replaced by the excretory phase of computed tomography urography CTU in many institutions, two independent observers retrospectively evaluated CTUs of primary or recurrent female pelvic tumors to rule out associations between CTU findings and subsequent urologic measures.
It appears that CTU is a sensible pre-therapeutic test for the urinary tract for primary and recurrent female pelvic tumors. Deutsche Leitlinien befuerworten bildgebende Untersuchungen bei Lokalrezidiven und Metastasen; fuer Primaertumoren gibt es keine einschlaegigen Empfehlungen. Da das Ausscheidungsurogramm durch die Ausscheidungsaufnahme der CT -Urographie CTU weitgehend abgeloest ist, wurde bei weiblichen Beckentumoren oder deren Rezidive der Zusammenhang zwischen CTU-Befunden und nachfolgenden operativen urologischen Massnahmen retrospektiv von 2 unabhaengigen Auswertern geprueft.
Volume-artifact reduction modality by helical CT of the anterior, middle and posterior carnial fossae. Vergleich mit der konventionellen kranialen CT. The object of this study was to determine the extent to which a new volume-artifact reduction VAR modality using helical CT was able to reduce artifacts in the anterior, middle and posterior fossae in comparison with conventional CT sequential mode. The results were evaluated by three radiologists; influences on image quality where scaled between 1 no artifact and 4 not assessable.
Eight regions of the anterior, middle and posterior fossae were evaluated. On average, artifacts were scaled at 2. Significant differences were seen at the eyeball, anterior to the petrosol bone, at the internal occipital crest, and at the level of the transverse sinus p CT with the VAR modality is superior to conventional, sequential CT in the area of the anterior, middle and posterior fossae.
Die Auswertung erfolgte durch drei Radiologen, die Bildqualitaet wurde in einer Skala zwischen 1 kein Artefakt und 4 Beurteilung der Region wegen Artefakten nicht moeglich angegeben. Acht anatomische Regionen in der vorderen, mittleren und hinteren Schaedelgrube wurden auf Beeintraechtigung durch Artefakte untersucht. Three-Dimensional post-myelographic CT reconstruction in the diagnosis and therapy planning for spinal development disorders; Dreidimensionale postmyelographische CT -Rekonstruktion in der Diagnostik und Therapieplanung spinaler Entwicklungsstoerungen.
Dysrhaphia is often associated with severe osseous aberrations of the spine such as, for example scoliosis, hemivertebra, and synostosis. With the advanced possibilities of the post-processing of CT -data segmentation, three-dimensional reconstruction , post-myelo- CT is an excellent method for the evaluation of osseous structures and the myelon in preoperative planning. Mit den verbesserten Moeglichkeiten der Datennachbearbeitung Segmentierung, 3D-dimensionale Rekonstruktion stellt die postmyelographische Computertomographie vor allem bei komplexen Fehlbildungen ein geeignetes Verfahren zur praeoperativen Beurteilung der ossaeren Strukturen der Wirbelsaeule und des Myelons dar.
Clinical applications of imaging reconstruction by virtual sonography. One of the pitfalls in managing multiple liver tumors is the difficulty in identifying individual tumors on ultrasonography. Computed tomography CT -assisted virtual sonography has been shown to improve sonographic diagnosis, however it requires additional equipment and software.
We have developed a simple reconstruction method of virtual sonography SRVS. We reconstructed SRVS mimicking ultrasonographic images, utilizing a workstation software attached to a multi-detector row CT system without any additional program. We have performed SRVS in 32 patients with 41 liver tumors that could hardly be identify on ultrasonography. SRVS assisted the identification of malignant form non-pathologic ones and thereby contributed to the appropriate clinical strategy including radiofrequency ablation RFA 18 tumors , liver biopsy 2 tumors , other therapies 4 tumors and follow-up 17 tumors.
We have developed virtual sonography using conventional CT software. SRVS seems useful in the clinical practice in managing liver tumors. CT -guided percutaneous neurolysis methods. State of the art and first results; CT -gesteuerte Neurolysen. Stand der Technik und aktuelle Ergebnisse.
Radiodiagnostik, Radiologische Universitaetsklinik Heidelberg Germany. We used 21G or 22G fine needles. All CT -guided percutaneous neurolysis methods require a proper blood coagulation.
Most common CT scanners are suitable for neurolysis if there is enough room for maintaining sterile conditions. This allows us to correct the position of the needle if we see improper distribution of the test block or unwanted side effects. Though inflammatory complications of the peritoneum due to puncture are rarely seen, we prefer the dorsal approach whenever possible. Seven of 20 legs showed at least transient clinical improvement after CT -guided lumbar sympathectomies; 13 legs had to be amputated.
Results of the methods in the literature differ. It was recently proved that sympathectomy not only improves perfusion of the skin but also of the muscle. The hypothesis of a steal effect after sympathectomy towards skin perfusion was disproved. Modern aggressive surgical and interventional treatment often leaves patients to sympathectomy whose reservers of collateralization are nearly exhausted.
We presume this is the reason for the different results we found in our patient group. For thoracic sympathectomy the clinical treatment depends very much on the indications. Results in celiac ganglia block also differ. Abdominal polytrauma and parenchymal organs; Abdominelles Polytrauma und Parenchymorgane. Die Verletzungsmuster sind komplex und erfordern eine grosse Erfahrung, um sie in Minutenschnelle analysieren zu koennen. Im nachfolgenden Uebersichtsartikel werden die radiologische Diagnostik und die klinisch-radiologische Graduierung der Verletzungen von Milz, Leber, Pankreas und Nieren beschrieben.
Es wird der Stellenwert der Ultraschalldiagnostik bei der Abklaerung von Polytraumapatienten beschrieben. Fuer die oben genannten Organe werden die wichtigsten traumaassoziierten Veraenderungen in der Computertomographie beschrieben und in Form praegnanter Fallbeispiele veranschaulicht. Die Computertomographie hat sich als bildgebendes Standardverfahren zur Abklaerung von Polytraumapatienten etabliert.
Die Anwendung der MDCT ist traumaabhaengig, und die Klassifizierung des Verletzungsgrads der parenchymatoesen Organe ist letztendlich fuer die weitere Therapie und Prognose entscheidend. Diagnostic imaging in polytrauma: Conventional radiography consisted of chest and cervical, thoracic and lumbar spine in two views as well as pelvis. Three combinations of organ specific CT were chosen: CT examination of 1 head and cervical spine, 2 head, cervical spine and chest, 3 head, cervical spine and abdomen.
The ratio of radiation dose between whole-body MSCT and radiography was This ratio was reduced to 3: Whole-body MSCT in polytrauma compared to conventional radiography with organ-specific CT induces a threefold increased dose in unfavorable situations and no increased dose in favorable situations. Nevertheless, routine use of whole-body MSCT should be critically evaluated and should be adapted to the clinical benefit.
Fuer die organspezifischen CT -Untersuchungen wurden 3 Kombinationen ausgewaehlt: Accuracy of spiral CT and 3D reconstruction in the detection of acute pulmonary embolism - development of an animal model using porcine lungs and technical specimens. Development of an animal model using porcine lungs and technical specimens; Diagnostik der akuten Lungenembolie mittels Spiral- CT und 3D-Rekonstruktion. Entwicklung eines Tiermodells und technischer Probekoerper im Ex-vivo-Experiment.
Mainz Germany ; Konerding, M. Standardisierte kuenstliche Emboli definierter Groesse und Geometrie wurden in Schweinelungen eingebracht. Ausguesse der embolisierten Gefaessbaeume mit roentgenkontrastgebendem Kunstharz simulierten das CT -morphologische Vollbild einer Lungenembolie. Die Bilddaten wurden dreidimensional rekonstruiert und die Exaktheit der detektierten Emboluslokalisation durch Korrelation mit dem Originalpraeparat verifiziert.
Die Messungen der technischen Probekoerper ergaben deutliche Abweichungen in Abhaengigkeit von der Groesse, der Orientierung zur z-Achse und der Rekonstruktionstechnik. Hierbei traten Ueberschaetzungen von bis zu 4 mm, Unterschaetzungen von bis zu 2,2 mm auf. Bei Praeparaten mit Hoehen von mm traten Schwankungen in einer Groessenordnung von ca. Die vorgestellten Ex-vivo-Modelle sind zur Simulation der akuten Lungenembolie gut geeignet. Die Genauigkeit der Embolusdetektion wird durch Lokalisation, Groesse, Orientierung und Rekonstruktionstechnik beeinflusst.
Utility of CT after sonography for suspected appendicitis in children: To improve diagnosis of pediatric appendicitis, many institutions have implemented a staged imaging protocol utilizing ultrasonography US first and then computed tomography CT. A substantial number of children with suspected appendicitis undergo CT after US, and the efficient and accurate diagnosis of pediatric appendicitis continues to be challenging. The objective of the study is to characterize the utility of CT following US for diagnosis of pediatric appendicitis, in conjunction with a clinical appendicitis score AS.
Imaging studies of children with suspected appendicitis who underwent CT after US in an imaging protocol were retrospectively reviewed by three radiologists in consensus. Chart review derived the AS range and obtained the patient diagnosis and disposition, and an AS was applied to each patient. Clinical and radiologic data were analyzed to assess the yield of CT after US. Studies of children mean age The positive threshold for AS was determined to be 6 out of Multi-modality imaging with SPECT- CT in orthopaedics combines the excellent sensitivity of scintigraphy with the morphological information of CT as a key for specific interpretation of findings in bone scans.
The result is an imaging modality with the clear potential to prove of value even in a competitive setting dominated by MRI, and to significantly add to diagnostic imaging in orthopaedics. SPECT- CT is of great value in the diagnostic evaluation after fractures, and - in contrast to MRI - it is well suited for imaging in patients with osteosyntheses and metallic implants.
In patients with osseous pain syndromes, actively evolving degenerative changes as a cause of pain can be identified and accurately localized. All images were evaluated by 3 radiologists for image quality using a semiquantitative score score value 1: In addition, dose measurements and measurements of high contrast resolution were performed in comparison to conventional and low-dose spiral CT using a high contrast phantom Catphan, Phantom Laboratories. Adequate image quality mean score values could be achieved with an applied dose comparable to low-dose CT in smaller joints such as wrist, elbow, ankle and knee.
A remarkably inferior image quality resulted in imaging of the hip, lumbar and thoracic spine mean score values in spite of almost doubling the dose dose increased by 85 percent. The image quality of shoulder examinations was insufficient mean score value 1. ISO-C-3D images of the hip and axial skeleton show a decreased image quality, which does not seem to be sufficient for diagnosing subtle fractures.
Siemens an Extremitaetengelenken und am Stammskelett. Imaging in syndrome complex diabetes mellitus. Current standards and future perspectives; Bildgebung im Syndromkomplex Diabetes mellitus. Diabetes mellitus is a highly prevalent multisystemic disorder with numerous potential complications and substantial socioeconomic consequences. In many cases, the patient history, physical examination and laboratory tests are not sufficient for a comprehensive evaluation of complicating disorders. Imaging modalities, such as sonography , computed tomography CT and magnetic resonance imaging MRI are of major significance in the evaluation of complicating disorders of diabetes according to current guidelines.
Examples include assessment of coronary artery disease, peripheral artery disease, stroke and diabetic foot syndrome. Technical developments allow a substantial reduction in radiation dose and scan time in CT and MRI, respectively and could therefore justify a broader application in this patient population. Furthermore, they could also be used for risk stratification, e. Prior to widespread application of advanced imaging techniques in this patient population, improved outcomes with respect to survival, quality of life and cost-effectiveness need to be demonstrated.
Diagnostic imaging modalities for the evaluation of the syndrome complex of diabetic disorders should be used according to the current guidelines but the use is predicted to increase given the high potential in this population. Die Folgeerkrankungen koennen oft nicht abschliessend mittels Anamnese, koerperlicher Untersuchung und laborchemischen Verfahren evaluiert werden. Sonography for diagnosis of benign and malignant tumors of the nose and paranasal sinuses.
The purpose of this study was to demonstrate the reliability of sonography for diagnosis of nose and paranasal sinus tumors. Ninety-six consecutive patients with tumors underwent sonography and computed tomography CT before surgical treatment. Tumor detectability and imaging findings were evaluated independently and then compared with pathologic findings.
Of 96 tumors, 75 were detected by sonography , for a detectability rate of By comparison, sonography showed a trend toward higher detectability of nasal vestibular tumors than CT Among the sonographic features, boundary, shape, internal echo, calcification, bone invasion, vascular pattern, and cervical lymph node metastasis all had significantly positive correlations with malignancy P benign and malignant tumors of the nose and paranasal sinuses. Consequently, sonography has high value for diagnosis of benign and malignant tumors of the nose and paranasal sinuses, especially for nasal vestibular tumors and small lumps on the wing of the nose.
This focused review describes the current use and future perspectives regarding transabdominal bowel sonography TABS. The technique for B-mode and Doppler is described and the use of ultrasound contrast and elastography is discussed. Pathology and subsequent imaging findings are focused on appe In conclusion we find that TABS is a fast, efficient, low-cost and non-ionization imaging technique without any patient discomfort Ultrasound-guided image fusion with computed tomography and magnetic resonance imaging.
Klinische Bedeutung fuer die bildgebende und interventionelle Diagnostik von Leberlaesionen. Abdominal ultrasound is often the first-line imaging modality for assessing focal liver lesions. Due to various new ultrasound techniques, such as image fusion, global positioning system GPS tracking and needle tracking guided biopsy, abdominal ultrasound now has great potential regarding detection, characterization and treatment of focal liver lesions. Furthermore, these new techniques will help to improve the clinical management of patients before and during interventional procedures. This article presents the principle and clinical impact of recently developed techniques in the field of ultrasound, e.
In diesem Artikel werden das Prinzip und die Anwendungsmoeglichkeiten dieser neuen Techniken anhand konkreter Beispiele in einem Kollektiv von 20 Patienten mit fokalen Leberlaesionen vorgestellt und erlaeutert. Follow-up and prognosis of thyroid carcinoma; Nachsorge und Prognose der Schilddruesenkarzinome. The follow-up of patients with differentiated thyroid carcinoma is based on guidelines of the appropriate scientific societies like the German Society of Nuclear Medicine DGN.
After successfull radioiodine treatment there are follow-up investigations in intervalls every [half] year, life-long including ultrasound, serum level of thyroglobulin, TSH, f T3, and f T4. Individual prognosis can be assessed by different scoring systems including factors like age, sex, size, grading, and extent of the disease.
The medullary carcinoma has a mediocre prognosis and similar follow-up intervals focusing on the tumor markers calcitonin and CEA and, if necessary, a variety of imaging methods. The anaplastic carcinoma with its bad prognosis needs individual palliative symptomatic follow-up. Die Prognose kann mittels diverser Scores bestimmt werden, die u.
Alter, Geschlecht, Grading, und Ausdehnung der Erkrankung beruecksichtigen. Das medullaere Karzinom hat bei mittlerer Prognose aehnliche Nachsorgeintervalle, orientiert sich an den Tumormarkern Kalzitonin und CEA und gegebenenfalls komplexer. Role of focused assessment with sonography for trauma as a The objective of the study was to review the utility of focused assessement with sonography for trauma FAST as a screening tool for blunt abdominal trauma BAT in children involved in high energy trauma HET , and to determine whether a FAST could replace computed tomography CT in clinical Konsensfaehige Vereinbarungen ueber eine standardisierte Untersuchungstechnik und einheitliche Befundung existierten bislang aber nicht.
Von der Arbeitsgemeinschaft ''Diagnostische Radiologie bei arbeits- und umweltbedingten Erkrankungen'' der Deutschen Roentgengesellschaft DRG wurde ein CT -Beurteilungsbogen eingesetzt, der auf Erfahrungen aus gutachtlichen Stellungnahmen, arbeitsmedizinischen nachgehenden Untersuchungen und Fortbildungskursen basiert und im Rahmen einer Multicenterstudie eingesetzt wurde. Ein weiter entwickeltes Schema einer internationalen Arbeitsgruppe P. Parker, USA wurde international getestet. Es soll dazu dienen, die computertomographische Befundung der arbeits- und umweltbedingten Lungen- und Pleuraveraenderungen zu standardisieren und international Vergleiche zu ermoeglichen.
Das Klassifizierungsschema hat einen rein deskriptiven Charakter, sodass alle Aspekte arbeits- und umweltbedingter Folgeerscheinungen an Parenchym und Pleura erfasst werden koennen. Obwohl einige der deskriptiven Bezeichnungen mit pneumokoniotischen Befunden verknuepft sind, wie z. Chest sonography is an established procedure in the stepwise imaging diagnosis of pulmonary and pleural disease. It is the method of choice to distinguish between solid and liquid lesions and allows the investigator to make an unequivocal diagnosis without exposing the patient to costly and stressful procedures.
This book presents the state of the art in chest investigation by means of ultrasonography. A number of excellent illustrations and the compact text provide concise and easy-to-assimilate information about the diagnostic procedure. Basic elements such as indications, investigation techniques and image artifacts are detailed in separate chapters.
Spiral and multislice CT. Spiral- und Multislice- CT. Spiral and multidetector techniques have improved the diagnostic possibilities of CT , so that image analysis and interpretation have become increasingly complex. This book represents the current state of the art in CT imaging, including the most recent technical scanner developments.
The second edition comprises the current state of knowledge in cT imaging. There are new chapters on image processing, application of contrasting agents and radiation dose. All organ-specific pathological findings are discussed in full. There is an introduction to cardio- CT , from calcium scoring and CTA of the coronary arteries to judgement of cardiac morphology. There are detailed scan protocols with descriptions of how to go about parameter selection. Practical hints are given for better image quality and lower radiation exposure of patients, guidelines for patient preparation and complication management, and more than images in optimum RRR quality.
With color doppler sonography, the directions of blood flow of the hepatic veins through the intervenous communication were fairly well demonstrated in all 5 cases. The obliteration of the hepatic segment of the IVC were segmental in 6 cases and diffuse in one case. CT demonstrated communicating vessels between the hepatic veins in 3 cases. Furthermore, systemic collateral vessels azygos and hemiazygos veins, veins along the abdominal wall, and internal mammary veins were demonstrated in all cases.
Liver cirrhosis was combined in all cases and hepatoma developed in 4 cases. Sonography is useful to detect the MOVC and to demonstrate hepatic venous obstruction and intrahepatic collateral vessels. Color doppler sonography is easily performed to show the direction of the blood flow through interconnecting vessels. CT shows the obliterated segment of the IVC clearly and multiple prominent systemic collaterals. Angiographic and hemodynamic evaluation of the mesoatrial shunt in patients with Budd-Chiari syndrome and inferior vena caval obstruction.
The caval obstruction may be due to thrombus or compression by an enlarged caudate lobe. Conventional portosystemic shunts are not possible in the presence of an obstructed IVC; the mesoatrial shunt is indicated in these patients. Between and , the authors studied 13 patients ten female, three male with Budd-Chiari syndrome and IVC obstruction in whom mesoatrial shunts were subsequently constructed. Polycythemia rubra vera was the most common predisposing condition. Preoperative evaluation included US, scintigraphy, CT, and angiography hepatic arteriography, hepatic venography and pressure measurements, inferior vena cavography, arterial portography.
Postoperatively shunts were assessed angiographically and hemodynamically, and several patients underwent CT. The shunts were catheterized via a brachial or femoral venous approach, which allowed pressures along the shunt from the superior mesenteric vein to the right atrium to be measured. The mesoatrial shunt is a relatively new procedure which is indicated in patients with the Budd-Chiari syndrome complicated by IVC obstruction. Shunt patency may be demonstrated arteriographically or with CT, but hemodynamic evaluation with measurement of pressure gradients is required to assess shunt function.
Interventional treatment for the occlusive hepatic veins in Budd-Chiari syndrome. To evaluate the interventional methods for occlusive hepatic veins in Budd-Chiari syndrome and its mid and long-term effects. Forty-two patients male 17 cases and female 25 cases aged from 18 to 57 years old mean A total of 92 hepatic veins were occluded. Among them, 29 left hepatic veins, 24 middle hepatic veins, 36 right hepatic veins, and 3 accessory hepatic veins were occluded. Thirty-four patients were accompanied with the stenotic or occlusive inferior vena cave IVC.
The interventional methods included: The successful recanalization was carried out in forty hepatic veins in 40 patients. PTA of occlusive veins was followed by stent implantation in 8 patients. The pressure of hepatic veins dropped from Transjugular intrahepatic portosystemic shunt for severe jaundice in patients with acute Budd-Chiari syndrome. From February to March , 37 patients with severe jaundice secondary to acute BCS were treated. Serum bilirubin, liver function, demographic data and operative data of the two groups of patients were analyzed.
The mean procedure time for TIPS was Budd-Chiari syndrome BCS is a rare clinical entity characterized by post-sinusoidal portal hypertension caused by the obstruction to the hepatic vein outflow. The diagnosis is suggested by hepatic scintigraphy and is usually confirmed by hepatic venography, inferior vena cavography and biopsy.
The scintigraphic finding of BCS caused by the obstruction of main hepatic vein has been reported to consist typically of hypertrophy of the caudate lobe with increased radionuclide accumulation. Such a typical finding has been accounted for by the fact that the venous outflow from the caudate lobe is preserved when the main hepatic vein is obstructed. But usually, the hepatic venous outflow from the caudate lobe is also obstructed in BCS due to inferior vena caval obstruction.
So hepatic scintigraphic findings of BCS due to inferior vena caval obstruction show different findings as compared with the BCS due to hepatic vein obstruction. We evaluate the hepatic scintigrams of the 13 cases of BCS due to inferior vena caval obstruction and review the literatures. The results are as follows: This is a useful finding suggesting BCS due to inferior vena caval obstruction. Transjugular intrahepatic portosystemic shunt for the treatment of Budd-Chiari syndrome.
Based on imaging manifestations, these patients were classified as follows: During the procedure, different puncture points were selected for fulfilling the real condition; including 7 cases from hepatic vein to portal vein; 4 cases from inferior vena cava to hepatic vein, 4 cases from the right hepatic vein to portal vein. After the operation, the follow-up evaluation of blood flow in the shunt was performed. All of these patients were successfully performed with TIPS, with average pressure of portal vein decreasing from 4. After 5 to 64 mouths follow-up, the recurrent upper gastrointestinal bleeding occurred in two patients due to stent stenosis and were well controlled through balloon angioplasty.
TIPS is an effective treatment for BCS with progressive liver dysfunction or severe portal hypertension with upper gastrointestinal bleeding and refractory ascites. In addition, it also contributes to the treatment of the recurrent or severe portal hypertension after the inferior vena cava or hepatic vein angioplasty. Full Text Available A year-old woman with end-stage renal disease secondary to autosomal dominant polycystic kidney disease was referred to a quaternary care center due to significantly increased abdominal girth. Her physical examination revealed tense ascites and abdominal collateral veins.
A L paracentesis improved abdominal discomfort and disclosed a transudate, suggestive of portal hypertension. A computed tomographic scan revealed massive hepatomegaly caused by multiple cysts of variable sizes, distributed throughout all hepatic segments. Contrast-enhanced imaging uncovered extrinsic compression of hepatic and portal veins, resulting in functional Budd-Chiari syndrome and portal hypertension.
Although image-guided drainage followed by sclerosis of dominant cysts could potentially lead to alleviation of the extrinsic compression, the associated significant risk of cyst hemorrhage and infection precluded this procedure. In this scenario, the decision was to submit the patient to a liver-kidney transplantation. Clinical application of Inoue-balloon in percutaneous transluminal angioplasty for Budd-Chiari syndrome. To investigate the feasibility and effect of recanalization of inferior vena cava with percutaneous transluminal angioplasty PTA by Inoue-balloon.
After PTA, the median interquartile range diameter of hepatic segment inferior vena cava increased from 0. The interventional procedures included: Percutaneous balloon dilatation PBD of inferior vena cava IVC , PBD and stent placement for IVC, hepatic vein angioplasty via trans jugular vein, hepatic vein angioplasty via transhepatic and trans jugular approach, accessory hepatic vein angioplasty, percutaneous dual balloon dilatation for IVC and hepatic vein, and percutanous dual stent placement for IVC and hepatic vein.
The serious complication of PTA and stent placement of BCS was penetration into the pericardium, endovascular stent migration into right atrium. Guiding of Color Doppler Ultrasound can improve the success of percutanous hepatic vein and reduce complications. Analysis of the complications in interventional treatment for Budd-Chiari syndrome. To discuss the causes and the prevention measures of the complications occurred after interventional therapy for different type of Budd-Chiari syndrome BCS.
The interventional procedures included PTA and stent placement of inferior vena cava IVC , percutaneous transhepatic recanalization and dilation PTRD of hepatic vein, percutaneous trans jugular or trans inferior vena cava recanalization, dilation and stent placement of hepatic vein and trans jugular intrahepatic portal-systemic stenting shunt TIPSS. The successful rate of interventional therapy was Interventional therapy is simple, safe and effective for the treatment of BCS, but its indications should be strictly considered and all kinds of effective prevention measures should be taken to avoid or to reduce the possible complications.
Budd-Chiari syndrome and secondary nodular regenerative hyperplasia of the liver. Case report with special reference to diagnostic imaging. Nodular regenerative hyperplasia is a benign epithelial proliferation of the liver with unknown etiology. We observed a female patient with Budd-Chiari syndrome and secondary nodular regenerative hyperplasia of the liver over a period of five years. Patient history, diagnostic imaging sonography, CT, MR imaging, angiography , and clinical course are demonstrated along with results of macroscopic and microscopic studies of explanted liver prior to liver transplantation.
The patient presented with various predisposing factors in combination that favour the development of nodular regenerative hyperplasia. Spectral CT imaging in patients with Budd-Chiari syndrome: Readers' subjective evaluations of the image quality were recorded. Two cases of Budd-Chiari syndrome complicated by hepatocellular carcinoma.
Hemodynamic study with computed tomography and venacavography. Two patients with Budd-Chiari syndrome complicated by hepatocellular carcinoma in whom CT and inferior venacavography were carried out are described. The imaging study with CT disclosed: A year-old male patient complained of general fatigue, ascites, and edema of the lower extremities. A chest x-ray film showed atelectasis of the right lung and pleural effusion of the right side.
Liver ultrasonography revealed stenosis of the middle and right hepatic veins. Venacavography revealed stenosis of the inferior vena cava and collateral circulation. Finally, abdominal NMR-CT clearly visualized lunate stenosis and antero-lateral deviation of the inferior vena cava.
In the first step, the input images are segmented to gain one image snippet for each transport box present in the image. We present graphics processing unit GPU data structures and algorithms to efficiently solve sparse linear systems that are typically required in simulations of multi-body systems and deformable bodies. We use modern programmable graphics hardware to ensure interactive frame rates. Journal of Real Estate Literature, 20 1 pp. For instance, the following options are addressed in this thesis: Political economics in retrospect: During the whole process only little user interaction is needed, which only takes place in the pre- and post-processing phases.
He was diagnosed as having secondary Budd-Chiari syndrome resulting from the deviation and stenosis of the inferior vena cava due to distortion of the surrounding tissues by the thickened pleura which was caused by chronic empyema. Orthotopic liver transplantation is the standard of care in patients with Budd-Chiari syndrome BCS , and transjugular intrahepatic portosystemic shunt TIPS has become an important adjunct procedure while the patient is waiting for a liver. Full Text Available A year-old woman with primary antiphospholipid syndrome was admitted to the Gastroenterology Department of our hospital with fever, acute abdomen, watery diarrhea, and extremely high levels of inflammatory parameters.
She had a history of left lower limb deep vein thrombosis and pulmonary embolism and was taking warfarin potassium. Acute gastroenteritis was suspected and an antibiotic was administered, but symptoms progressed. Abdominal ultrasonography showed occlusion of the left hepatic vein and the middle hepatic vein and her D-dimer level was high.
Accordingly, Budd-Chiari syndrome was diagnosed and high-dose intravenous infusion of heparin was initiated. Her abdominal symptoms improved and the levels of inflammatory parameters and D-dimer decreased rapidly. It is known that antiphospholipid syndrome can be complicated by Budd-Chiari syndrome that usually occurs as subacute or chronic onset, but acute onset is rare. It is difficult to diagnose acute Budd-Chiari syndrome complicating antiphospholipid syndrome and this complication generally has a poor outcome.
However, the present case can get early diagnosis and successful treatment with tight anticoagulant therapy. Budd-Chiari syndrome due to prothrombotic disorder: Our objective was to evaluate efficacy and patency of metallic stent placement for symptomatic Budd-Chiari syndrome BCS due to prothrombotic disorders. Clinical efficacy and stent patency was evaluated by clinical and Doppler follow-up. After a mean follow-up of 21 months, 6 patients had fully patent stents without reintervention primary stent patency: Two patients with hepatic vein stenosis had stent thrombosis and died 4 months after procedure.
Stent placement is a safe and effective procedure to control of symptomatic BCS. Prothrombotic disorder does not seem to jeopardize patency in anticoagulated patients. Budd-Chiari syndrome and heparin-induced thrombocytopenia in polycythemia vera: Successful treatment with repeated TIPS and interferon alpha.
The postpartum period is a precipitating cofactor. The diagnosis was established using CT scan, MRI, and Doppler ultrasonography of abdominal vessels and the laboratory findings were compatible with PV. TIPS procedure was successfully repeated and heparin was replaced with Fondaparinux and then vitamin K antagonist. The treatment with interferon alpha-2A, started after the normalization of liver functions, resulted in a complete remission within 6 months. A Systematic Review and Meta-Analysis. However, the reported prevalence of pregnancy-related BCS varied considerably among studies.
Our study aims to systematically review this issue. Twenty of them were eligible. The pooled prevalence was 6. Among them, one study was carried out in Africa with a prevalence of In conclusion, pregnancy is a relatively common risk factor for BCS, but there is a huge variation in the prevalence among studies.
Physicians should be aware of pregnancy-related BCS. Regenerative nodules in patients with chronic Budd-Chiari syndrome: A longitudinal study using multiphase contrast-enhanced multidetector CT. Our aim was to evaluate the serial evolution of regenerative nodules in patients with Budd-Chiari syndrome BCS treated with portal-systemic shunts, using multiphasic multidetector computed tomography MDCT. Five patients each underwent three MDCT exams over an extended period ranging from 36 to 42 months.
Two radiologists in consensus retrospectively reviewed each exam for each patient. Individual nodules were grouped according to size size I: All patients underwent dynamic enhancement examinations with multi-slice CT within 1 week before DSA. Compared with the results of DSA, we analyzed the dynamic enhancement regulations of liver in BCS, estimated the value of dynamic enhancement CT exams and CTA techniques in judging the obstruction level and showing collateral vessels.
Of all 28 cases, CT correctly showed the obstruction level in 26 cases, and 2 had incorrect results which proved to be membranous obstruction of the inferior vena cava superior to diaphragm. In 22 cases with hepatic vein obstructions, hepatic parenchyma displayed typical patchy enhancement in 19, atypical patchy enhancement in 3. Simultaneously, CT showed stenosis and rigidity of portal vein branches in 20, enlargement of hepatic artery in 14, hepatic collateral vessels in 20 out of 22 cases. In 6 cases with simple obstruction of inferior vena cava, hepatic changes were not found.
Collateral circulations in or out of liver corresponded to the obstruction level. Dynamic enhancement examinations with multi-slice CT can correctly reflect the hepatic hemodynamic changes. Transverse images, combined with CTA, can explicitly display the obstruction level of vascular lesions and collateral circulations in BCS. Scientific publications on portal vein thrombosis and Budd-Chiari syndrome: The publication year, country, type of paper, study design, and number of citations were summarized. The number of papers gradually increased over time.
Clinical studies were the most common type of paper PVT: Furthermore, fewer than half of the clinical studies with more than 10 patients were of good quality PVT: According to the study design, the good quality papers were classified as cohort studies PVT: Despite an increase in the number of papers regarding PVT and BCS over time, most of the papers had a small sample size, suggesting the necessity of large cohort studies or randomized controlled trials.
Factor V Leiden mutation, prothrombin gene mutation, and deficiencies in coagulation inhibitors associated with Budd-Chiari syndrome and portal vein thrombosis: In a collaborative multicenter case-control study, we investigated the effect of factor V Leiden mutation, prothrombin gene mutation, and inherited deficiencies of protein C, protein S, and antithrombin on the risk of Budd-Chiari syndrome BCS and portal vein thrombosis PVT.
We compared 43 BCS. In a collaborative multicenter case-control study, we investigated the effect of factor V Leiden mutation, prothrombin gene mutation, and inherited deficiencies of protein C, protein S, and antithrombin on the risk of Budd-Chiari syndrome BCS and portal vein thrombosis PVT , We compared 43 BCS.
Detection and characterization of Budd-Chiari syndrome with inferior vena cava obstruction: Comparison of fixed and flexible delayed scan time of computed tomography venography. Image quality was classified as either good, moderate, or poor. Inter-observer agreement was assessed using Kappa statistics. There was no significant difference in IVC blood flow velocity between the two groups. Overall image quality, surrounding structures and IVC obstruction morphology delineation on the flexible delayed scan time of CTV images were rated better relative to those obtained by fixed delayed scan time of CTV images ptime of CTV.
The flexible delayed scan time of CTV was associated with better detection and more reliable characterization of BCS with IVC obstruction compared to a fixed delayed scan time. The liver function tests were raised. Besides showing a progressive hepatosplenomegaly and a cirrhotic liver alteration, the MRI revealed multiple new nodular lesions in all liver segments. These lesions showed typical patterns in the precontrast images, while there was an arterial and a persistent portal venous enhancement. The additionally performed contrast-enhanced ultrasonography showed a strong zentrifugal arterial enhancement of the lesions followed by an isoechoic enhancement in the portal venous and delayed liver phase.
Differentiation between regenerative nodules like LRN and hepatocellular carcinoma HCC in cirrhotic livers is crucial, and the target sign in the hepatobiliary phase of Gd-EOB-DTPA as well as the centrifugal arterial enhancement followed by an isoenhancement during a CEUS might be useful for establishing the correct diagnosis of such hypervascular lesions with proliferated and likely aberrant bile ducts.
Full Text Available Budd-Chiari syndrome can be defined as an interruption or diminution of the normal blood flow out of the liver. Patients with Budd-Chiari syndrome present with varying degrees of symptomatology that can be divided into the following categories: The subacute form is the most common presentation.
A majority of patients with Budd-Chiari syndrome have an underlying hypercoagulability state. We present the case of a young woman with Crohn's disease on oral contraceptives who developed bilateral pulmonary thromboembolism and Budd-Chiari syndrome. Os demais seis casos foram tratados primariamente com TIPS. To evaluate the use of transjugular intrahepatic portosystemic shunt TIPS and suprahepatic venous stenting in the management of Budd-Chiari syndrome , emphasizing the indications, technical aspects and the advantages of the procedure.
Diffuse and vascular hepatic diseases; Diffuse und vaskulaere Lebererkrankungen. In addition to focal liver lesions, diffuse and vascular disorders of the liver represent a wide spectrum of liver diseases which are from the radiological point of view often difficult or nearly impossible to diagnose.
Classical diagnostic methods are computed tomography and magnetic resonance imaging in addition to ultrasound. Diffuse parenchymal damage caused by diseases of various etiologies is therefore difficult to evaluate because it often lacks characteristic morphological features. For most diffuse liver diseases, however only nonspecific changes are visualized. Vascular pathologies of the liver, such as the Budd-Chiari syndrome and portal vein thrombosis, however, can usually be diagnosed very clearly using radiology and there is also a very effective interventional radiological treatment.
Chronic diseases very often culminate in liver cirrhosis which is highly associated with an increased risk of liver cancer. Klassische diagnostische Verfahren sind dabei neben dem Ultraschall die Computertomographie und die Magnetresonanztomographie. Diffuse Parenchymschaeden, bedingt durch Erkrankungen unterschiedlichster Aetiologie, sind deshalb schwierig evaluierbar, weil haeufig charakteristische bildmorphologische Merkmale fehlen.
The effects of L-carnitin in Budd-Chiari syndrome in a domestic cat. Full Text Available This paper describes a thrombosis in the vena cava caudalis of a 15 year-old cat with ascites. Trauma and eventually feline enteric corona virus infection in the cat were not detected. In the intrahepatic region, a blockage of vena cava caudalis was brought to light by ultrasonographic imaging. An aspirate of abdominal fl uid revealed modified transudate.
Liver enzyme levels were increased in the serum sample of the cat. Liver protection diet with L-carnitine, diuretic therapy and antimicrobial drugs were administrated for treatment of the cat. During the continuous treatment, the amount of abdominal fluid decreased, but never completely absorbed.
L-carnitine was administered to the cat during the time of treatment, and subsequently the levels of liver enzymes decreased. However, the cat died because of recurrent ascites and persistent thrombosis. In conclusion, ultrasonographic examination was very reliable, non-invasive and highly useful diagnostic method for BCS and L-carnitine has crucial effects on the quality of life, energy metabolism and liver enzyme levels. However, the blockage of the vena cava caudalis could not completely respond to medical treatment and thrombosis should be eliminated by surgical intervention.
This paper describes a thrombosis in the vena cava caudalis of a 15 year-old cat with ascites. The levels of total oxidant status TOS and total antioxidant status T Comparison of retrievable stents and permanent stents for Budd-Chiari syndrome due to obstructive inferior vena cava. The retrievable stents was removed eventually after thrombus disappeared. Patients were subsequently followed-up by color Doppler sonography or CT scanning. All retrievable stent placements were successfully, and 37 retrievable stents were retrieved 8 to 29 days later. Forty-two stents were implanted in PS Group.
One failure retrieval of retrievable stents occurred, and two failures of cannulations were found in PS Group. Two deaths may procedure-related and died from acute pulmonary thromboembolism perioperatively. One patient developed acute cerebral infarction and recovered after treatment. In PS Group, minor complications were found in 3 patients. Cumulative 1-, 3-, and 5-year secondary patency rates were This article is protected by copyright. False-positive image of portal thrombosis with MRI: Observation in a Budd-Chiari syndrome. This observation illustrates how difficult it is to interpret the intravascular signal observed with MRI in cases of portal hypertension.
A signal occupying the entire lumen of the portal trunk and branches can be seen, which is constantly observed in the axial as well as coronal planes in the 3 series studied. It is hypointense relative to the liver on T1-weighted images, hyperintense on T2-weighted images: Ultrasound combined with pulsed Doppler demonstrates the stagnant blood within the patent portal system. This kind of artifact, which is produced by a very slow flow or even by the standstill of flow, is much more difficult to recognize than the common flow artifacts; the criteria put forward by various authors to distinguish between artifacts and thrombosis are of no avail in this case.
Examinations must able to confirm or rule out portal thrombosis in the case of portal hypertension with deceleration of flow. In practice, ultrasound studies, combined with pulsed Doppler in the best cases, is therefore indicated as a first-intension technique [fr. Analysis of expression of von Willebrand factor, endothelin-1, vascular endothelial growth factor in Budd-Chiari syndrome with membranous obstruction. To investigate whether the injured vascular endothelial plays an important role in the membranous formation of the inferior vena cava IVC.
There were 40 cases of membranous obstruction of inferior vena cava MOVC in the experimental group and 40 arrhythmic inpatients in the control group from affiliated hospital. There were 23 males and 17 females in experimental group while 21 males and 19 females in control group, and the age were All of them had no anti-coagulation clotting drug history and smoking history, no hypertension, no pulmonary artery hypertension, no coronary heart disease, no valvular disease, no myocardial disease, no blood disease, no diabetes, no connective tissue disease and malignancy, and liver and renal function must be normal.
The results were analyzed with independent sample t-test. Systemic lupus erythematosus; Budd-Chiari. Syndrome ; lupus anticoagulants; thrombosis; antiphospholipid syndrome. Measurement of secondary cosmic radiation and calculation of associated dose conversion coefficients for humans; Messung sekundaerer kosmischer Strahlung und Berechnung der zugehoerigen Dosiskonversionskoeffizienten fuer den Menschen.
Due to secondary cosmic radiation SCR , pilots and flight attendants receive elevated effective doses at flight altitudes. For this reason, since aircrew members are considered as occupationally exposed, in Germany. This work deals with the calculation of dose conversion coefficients DCC for protons, neutrons, electrons, positrons, photons and myons, which are crucial for estimation of effective dose from SCR. Furthermore, measurements of neutron fluence spectra - which contribute the major part to the effective dose of SCR - were carried out at the Environmental Research Station Schneefernerhaus UFS located at m above sea level nearby the Zugspitze mountain, Germany.
These measured neutron spectra, and additionally available calculated spectra, were then folded with the DCC calculated in this work, and effective dose rates for different heights were calculated. Cranial nerves - spectrum of inflammatory and tumorous changes; Hirnnerven - Spektrum entzuendlicher und tumoroeser Veraenderungen. Inflammatory processes as well as primary and secondary tumorous changes may involve cranial nerves causing neurological deficits. In addition to neurologists, ENT physicians, ophthalmologists and maxillofacial surgeons, radiologists play an important role in the investigation of patients with cranial nerve symptoms.
Multidetector computed tomography MDCT and particularly magnetic resonance imaging MRI allow the depiction of the cranial nerve anatomy and pathological neural changes. This article briefly describes the imaging techniques in MDCT and MRI and is dedicated to the radiological presentation of inflammatory and tumorous cranial nerve pathologies.
Budd-Chiari syndrome , a blockage in one or more veins that Although extremely rare, children may also require a TIPS procedure. Autoimmune haemolytic anaemia with giant cell hepatitis. Budd-Chiari and inferior caval vein syndromes due to membranous obstruction of the liver veins. Successful treatment with angioplasty and transcaval TIPS. The case is presented of a year-old Caucasian patient with Budd-Chiari syndrome due to membranous obstruction of the liver veins and inferior caval vein syndrome as a result of secondary hyperplasia of the caudate lobe of the liver, obstructing the caval vein.
Diseases of the peritoneum and mesenterium; Erkrankungen von Peritoneum und Mesenterium. Peritoneal diseases can be seen in the different imaging modalities either as fluid collections or solid tumors along the ligaments, mesenteries, and spaces of the peritoneal cavity. The broad spectrum of different abnormalities includes inflammatory, infectious, traumatic, and neoplastic diseases.
In this article, a large variety of peritoneal abnormalities such as ascites, peritonitis, intraperitoneal hemorrhage, and both primary and secondary peritoneal tumors are discussed. The different imaging modalities, characteristic radiological features, and typical pathways of anatomic spread are explained. Dieses breite Spektrum der pathologischen Veraenderungen beinhaltet entzuendliche, infektioese, neoplastische und verschiedenste Erkrankungen anderer Genese.
In vorliegendem Artikel wird ein grosses Spektrum dieser Pathologien wie Aszites, Peritonitis, intraabdominelle Blutung und verschiedene primaere und sekundaere peritoneale Tumoren vorgestellt. Des Weiteren wird der Einsatz der verschiedenen radiologischen Untersuchungsmodalitaeten, v. Die charakteristischen Bildgebungsmerkmale und die typischen anatomischen Ausbreitungswege werden erklaert.
Osteoarthritis - histology and pathogenetic concepts; Arthrose - Histologie und pathogenetische Ansaetze. Knorpelabbau als sekundaere Arthrose zu bezeichnen. Die Pathogenese der primaeren Arthrose basiert auf einer intrinsischen Erkrankung des Knorpels, bei der biochemische und metabolische Veraenderungen zu einem Zusammenbruch fuehren. In den letzten Jahrzehnten wurden jedoch auch Modelle entworfen, die andere Gelenkanteile wie Knochen oder den Bandapparat in den Mittelpunkt der Genese stellten. Veraenderungen des subchondralen Knochens, die dem Knorpelabbau vorangingen, wurden beschrieben, und lenkten die Aufmerksamkeit auf diese Region als Ort des primaeren Geschehens.
Andere Untersuchungen konzentrierten sich auf die metabolische Aktivitaet der Chondrozyten im unveraenderten Knorpelgewebe von Arthrosepatienten. Der ausschlaggebende Faktor fuer den Krankheitsbeginn ist jedoch immer noch unklar. Dieser Uebersichtsartikel beschreibt die morphologischen Veraenderungen in Abhaengigkeit des Krankheitsstadiums und versucht einen Einblick ueber verschiedene pathogenetischen Konzepte zu schaffen. Biomechanics of the arch of the foot. Pre- and postoperative radiological examination; Biomechanik des Fussgewoelbes. Prae- und postoperative Radiometrie.
In der seitlichen stehenden Aufnahme sind Lisfranc-Gelenk-Instabilitaeten und Veraenderungen des talometatarsalen Winkels zu sehen. Bei Versagen der konservative Therapie ist eine Operation mit korrigierender Osteotomie der knoechern fixierten Fehlstellung in Kombination mit Band- und Sehnenrekonstruktion der goldene Standard. Auch hier stellt die belastete stehende Roentgenuntersuchung den Standard fuer Follow-up-Untersuchungen und Kontrollen dar.
Technologies for the commercial energetic utilisation of waste wood and used wood; Technologien zur energetischen Nutzung von Holzabfaellen und Gebrauchsholz im gewerblichen Bereich. Due to the frequent contamination of wood with wood preservatives, coatings, adhesives, paints and other non-wood materials the conversion of production residues and various types of used wood to energy appears to be fraught with problems. However, extensive studies conducted during the past years have shown that most problems regarding combustion residues and emissions have been overestimated.
Thanks to new technologies it is now possible to avoid or at least reduce the formation of pollutants during combustion of even complexly contaminated waste wood. Environmentally acceptable combustion of wood presupposes complete combustion, effective dedusting, and primary measures for nitrogen oxide control. Depending on the type of feedstock and the relevant emission limit values one may optionally include secondary nitric oxides removal measures and control techniques for partially volatile heavy metals and halocarbons.
Moreover, firing plants must be so conditioned as to keep the new synthesis of dioxins at a low level. Tatsaechlich sind - wie umfangreiche Untersuchungen der letzten Jahre gezeigt haben - die meisten Probleme in Hinblick auf Ausbrand und Emissionen ueberschaetzt worden. Durch Weiterentwicklung von Anlagen- und Regelungstechnik ist es heute moeglich, die Schadstoffbildung bei der Verbrennung auch komplex belasteter Holzabfaelle zu vermeiden oder zu vermindern. Voraussetzungen einer umweltvertraeglichen Verbrennung von Holz sind - ein guter Ausbrand, - eine effektive Entstaubung, - und primaere Massnahmen der Stickstoffoxidminderung.
Optional kommen je nach Brennstoff und Emissionsgrenzwert noch sekundaere Entstickungsmassnahmen und Minderungstechniken fuer partiell. Magnetic resonance imaging MRI in diffuse liver diseases. MRI Magnetic Resonance Imaging was performed in 74 patients with chronic hepatitis, liver cirrhosis, idiopathic portal hypertension, Budd-Chiari syndrome , extrahepatic protal vein occlusion, Wilson disease and hemochromatosis.
We measured relaxation time of the liver and the spleen in these patients and compared MRI with CT in the diagnostic capability. MRI was superior to plain CT in the detection of collateral vessels in liver cirrhosis and extrahepatic protal vein occlusion. MRI could also demonstrate the occluded part of the inferior vena cava in Budd-Chiari syndrome. However, MRI was almost the same as CT in the visualization of the hepatic configuration in liver cirrhosis. In liver cirrhosis, T1 values of the liver and the spleen were longer than those in normal controls, and T1 values of the liver were correlated with ICG R Hepatic T1 values in Budd-Chiari syndrome were longer than those in normal controls.
Sport und soziale Integration. Sport und soziale Integration: Calibration and characterisation of solar cells: Comparison of pulsed and steady-state simulation of sunlight; Kalibrierung und Charakterisierung von Solarzellen: Vergleich von gepulster und stationaerer Sonnensimulation. Pulsed solar simulators are widely used for the secondary calibration of photovoltaic modules against reference solar cells, because the uniformity and spectral match requirements for large-area class A or B simulators can be met more easily and economically by pulsed than by steady-state simulators.
Moreover, a pulsed simulator produces little additional heat that could increase the temperature of the PV device during the measurement. However, the transient measurement of current-voltage characteristics during a single flash in the ms range often induce distortions or hysteresis effects especially in high-efficiency or high-resistivity silicon solar cells. The sweep-rate distortions have systematically been studied, revealed and simulated by computation as a function of cell technology and measurement conditions.
Based on this fundamental analysis, the distortions that have been found to be unavoidable can both be explained and fully be corrected. A simple correction procedure including two auxiliary characteristics measurements in the dark has been developed for the transformation of the distorted IV-curve into the undistorted characteristics. Moreover, detailed improvements in the calibration of reference solar cells have been carried out and prototypes of large-area reference cells have been developed. New as well as developed transient and steady-state laboratory methods for the optoelectronic characterization of solar cells have been tested which can be used to study impurity effects where non-destructive and spatially resolved techniques were the main topic of interest.
Grossflaechige Strahlungsfelder der gleichen Qualitaet. Transjugular liver core biopsy: Bern Switzerland ; Dufour, J. Bern Switzerland ; Zimmermann, A. Nutzen, Durchfuehrbarkeit und Komplikationsrate der transjugulaeren Leberbiopsie mit einem halbautomatischen Stanzbiopsiesystem wurden retrospektiv evaluiert. Als erfolgreiche Biopsie wurde die Gewinnung eines Gewebszylinders definiert, der eine eindeutige histologische Diagnose gestattete. Komplikationen wurden anhand der Akten erfasst.
In die Mortalitaetsrate flossen alle Todesfaelle innerhalb von 30 Tagen ein. Die prozedurbedingte Mortalitaet umfasst alle Todesfaelle, die mit der Leberbiopsie in Verbindung standen. In 5 Faellen scheiterte sie an einem unguenstigen Lebervenenabgangswinkel 1 bei einem Patienten mit Budd-Chiari Syndrom und vollstaendigem Lebervenenverschluss, 4 bei schwierigen anatomischen Verhaeltnissen.
Bei 22 Patienten wurde einmal, bei 45 zweimal und bei 14 Patienten dreimal oder oefter - jeweils in gleicher Sitzung - gestanzt. Prevention, screening and therapy of thyroid diseases and their cost-effectiveness; Praevention, Screening und Therapie gutartiger Schilddruesenerkrankungen unter dem Aspekt von Kosten und Nutzen. Klinik und Poliklinik fuer Nuklearmedizin. Insbesondere die Erhebung eines Geldwertes pro gewonnenem Lebensjahr gestaltet sich methodisch schwierig: Der Nutzen praeventiver Massnahmen ist weit in die Zukunft verlagert. Der Einfluss einer unbehandelten Schilddruesenerkrankung auf die Lebenszeit wird ebenfalls erst durch einen langfristigen Horizont und dann eher epidemiologisch als individuell zu erfassen sein.
Basedows aus entscheidungstheoretischer Sicht sehr kosteneffektiv. Lebensjahr in einer qualitativ hochwertigen gesundheitsoekonomischen Studie bereits belegt werden. Die Therapiestrategien bei gutartigen Schilddruesenerkrankungen tertiaere Praevention zielen auf eine Minimierung sekundaerer Krankheitsfolgen Vorhofflimmern, Myokardinfarkt, Herztod und iatrogener Nebenwirkungen. Beispiele fuer eine solche tertiaere Praevention sind die definitive Therapie Radioiodtherapie der Immunhyperthyreose M.
Weiterhin wird ein Authoring-Ansatz vorgestellt, mit dem die Zuordnung des Verhaltens zu den Objekten der Szene visuell und somit durch die Endanwender bzw. Es werden zwei Industrieszenarien vorgestellt, in denen dieser Ansatz genutzt wurde, um den VR-Einsatz zu realisieren. Dazu ist es zum einen notwendig, die VR-Systeme an die Bedarfe der schiffbaulichen Produktentwicklung anzupassen und in die betriebliche DV-Landschaft zu integrieren und zum anderen bestehende Anwendungshemmnisse zu beseitigen.
Nach diesem Vorgehen wurden im Projekte folgende wesentliche Ergebnisse erarbeitet: Lukas, Uwe von ; Mesing, Benjamin. Lukas, Uwe von ; Audersch, Stefan. Die Sammlung und Auswertung von Daten, insbesondere Messdaten unterschiedlicher Sensoren, ist ein wichtiger Teilbereich der Meeresforschung und Meerestechnik. Game-based training is a promising approach to reduce costs on the one hand and reach a constant level of trainee motivation and involvement on the other hand.
Computer games pave the ground for offering a simulated world that is used for implementing realistic training scenarios. Advances of the consumer-focused game industry do not only provide off-the-shelf high-end graphics and computing power but also sophisticated game engines that allow the concentration on the content whilst interaction and rendering is mainly done by the game engine. The paper presents the experiences of the authors in applying game-technology in the area of shipboard firefighting. It starts with a concept, in how to embed game-based training in the process of maritime education - considering the benefits and limitations of this specific simulator.
Later on we describe the technological framework that is used in the authoring phase as well as during the runtime. Furthermore, we highlight the user feedback and compare our approach with the classical way of shipboard fire-fighting. The paper closes with an outlook to further research in this area. Diesen kann mit modernen Ausbildungskonzepten wie compulerbasiertem Lernen und Lernspielen Rechnung getragen werden. Experten und reales Feuer sind nicht ersetzbar. Today, there exists a multitude of different VR solutions, each providing its own advantages and application areas.
Needless to say that companies use the VR solutions best suited for their specific purposes. But commercially available VR applications often do not cover all the individual use cases which might occur in different companies - a fact which makes extra customisation necessary. This especially holds true for the shipbuilding industry with its specific needs not addressed by today's VR solutions.
Furthermore, VR applications are mostly incompatible among each other which makes the collaboration of different tools impossible, at the moment. Product counterfeiting is a major challenge for all industry nations worldwide. It must be fought at several levels, ranging from policy, over legal issues up to organization and technical measures. This article concentrates on the technical perspective, especially the challenges and potential solutions in the field of information technology. On the one hand, the internet is introducing a high risk in collaborative product development.
On the other hand, there are many tools and technologies available to protect intellectual property. Various concrete IT solutions are available that range from data filtering over enterprise rights management up to trusted computing. The joint activities of the German automotive sector for secure product creation are presented and an outlook to further research and development is given.
Lukas, Uwe von ; Vahl, Matthias. Weitere Eingangsdaten sind die Farb- und Reflektionseigenschaften der Materialien. The ongoing development of virtual reality systems allows it nowadays to use them in many different areas. Aside the already known usage of those systems in fields such as simulations or entertainment software, virtual environments gained more and more importance in the field of design and product development over the past few years. In particular for the phases of engineering, testing and marketing virtual environments can be very supportive.
For instance design mistakes can be detected in early stages, the integration of the product with other system can be tested or possible versions of the product can be demonstrated to the customer before it is already build. Within the frame of this work an Authoring-System is going to be developed which will be capable of preparing and transforming product data of different sources e.
The system will convert the structure, which is given by the data, into a displayable format. This means the product data has to be extended with interaction abilities and the metadata additional information about the product like material or weight given by the product data has to be processed for later use. The product data which is given as input to the authoring can be divided into geometry data, which will describe the appearance of objects in the virtual system and the already mentioned metadata on the other hand.
There will be an interface defined which allows the system to obtain metadata from different sources and also make it easy to integrate new sources. Computer Graphics is an important technology for progress in virtual product creation. Visualization and interaction with digital products are crucial to detect and solve problems in the design and the manufacturing process as early as possible. The concept of the virtual ship offers plenty of potential to improve communication amongst the involved disciplines, to compare alternative designs and to simulate production steps as well as usage of the ship and different situations.
Highly interactive technologies such as Virtual and Augmented Reality are available and can be applied throughout the whole life cycle. This paper summarizes the state of the art from a technology perspective and presents typical usage scenarios ranging from design and production over marketing up to maintenance and training. Upcoming trends in hard- and software are highlighted and the paper concludes with an outlook to further research in this challenging field.
The paper highlights the importance of communication and collaboration in engineering and discusses driving factors concerning this matter. Afterwards the author presents a general model for collaboration, including the technical, the strategic, the organizational, and the staff-realted viewpoint. The technical viewpoint is presented in more detail n the main part of the article by giving examples for explicit and implicit collaboration.
After presenting experiences from communicative engineering in the automotive as well as in the shipbuilding industry, the paper concludes with a summary and some outlook to further work. Cross-domain engineering is a highly multidisciplinary approach that opens the door for innovation in many industrial areas. Innovation in products and processes is a constant challenge to ensure the competitiveness of our economy. Applied research plays a major role in this context as an instrument for identifying promising technologies and preparing them for industrial use.
With the application focus of cross-domain engineering as a filter, this paper illustrates innovation topics of the Fraunhofer-Gesellschaft and presents selected research work based on computer graphics technologies. Finally, the authors give an indication of future work by highlighting challenges for computer graphics in cross-domain engineering.
Dazu wird ein Konzept entwickelt und die Realisierbarkeit an einer prototypischen Umsetzung gezeigt. Nowacki, Steffen; Lukas, Uwe von. By providing a sound information model and a well-performing interface for synchronous and asynchronous access to product data, we now have the chance to avoid proprietary integration solutions. Based on the standard and a modular approach with reusable components we can push the integration task into another dimension: The High-Level Integration presented in this paper does not concentrate on low level problems such as connecting to heterogeneous systems or mapping of data types.
The companies now can focus on the business logic - as demanded by the end-users. Organizational innovations like Global Engineering and the growing importance of the Internet as a communication backbone for distributed processes induce a risk for the integrity as well as the confidentiality of digital product data.
This paper gives an overview of the challenges and technical solutions in the area of IT security for E-Engineering. Basic technologies and specific solutions for CAD and product data in general are presented and an outlook towards further research in this field is given. Die Parametrisierung aller Module erfolgt zur Laufzeit, so dass der Einfluss dieser auf den gesamten Trackingprozess effizient untersucht werden kann.
InViS verfolgte deshalb einen integrativen Ansatz und zielte auf eine offene Plattform zur Einbindung verschiedener Software-Werkzeuge. The realisation of efficient product development and production processes forms the basis for economic success. It is of vital importance to keep up with the technological development in order to be able to react to new developments in time and furthermore to actively participate in the future evolution of product development related technologies.
The study "Setting the Course for Innovative Engineering" has been conducted with the major objective of identifying IT-potentials in product creation and possible realisation strategies up to the year This study pays special attention to the domains mentioned above and describes comprehensively the respective states of the art, deficits and requirements, trends and visions, realisation subjects and strategies, as well as benefits and success criteria.
The present book describes the results of the study. Funk, Wolfgang; Lukas, Uwe von. In the context of global engineering supply chains the virtual product is subject to a constant risk of espionage, fraud and sabotage. Beside other security technologies, digital watermarks are one approach to raise the security level in a company. In this article we concentrate on embedding digital watermarks into 3D product models. A digital watermark can be used to store and retrieve information such as the originator or the legitimate receiver of the model.
We give a short overview of existing watermarking technologies for polygonal and parametric models and a more detailed description of an algorithm that is well suited for the track-and-trace scenario.
Analyse des Produktlebenszyklus-Konzepts und sein Anwendungsbereich im Marketing (German Edition) - Kindle edition by Achim Schätzl. Download it once . Bei einer Reihe von Produkten ist es relativ gut möglich abzusehen, nach welcher Absatzmenge der Markt gesättigt sein wird. Daher eignet sich die.
Concrete usage scenarios illustrate technical alternatives and the integration in the product creation environment. Lukas, Uwe von ; Nowacki, Steffen. Integration in the area of product data management systems is still an open topic. Even though various approaches for offline typically based on STEP and now also for online integration have been developed, the effort and costs of integration are still too high. What we need in the context of a highly integrated environment or a collaborative virtual environment, including systems such as CAD, CAE, Virtual Reality and tele-cooperation, is an open and powerful approach for exploring and modifying product data.
This paper puts forward additional arguments for dealing with this topic in terms of motivation and afterwards presents an approach employing a standard access interface as the core concept. Based on the presentation of the interface, the paper illustrates usage and advantages of the approach on the basis of two application scenarios: The paper ends with a summary and an outlook on future work.
So werden aufwendige Entscheidungen zur Laufzeit vermieden. Typical problems in this context include the variety of data models, the integration of different access interfaces and efficient implementation of the business logic. Even though partial solutions do exist for all areas, there is no general approach that functions efficiently with very large data sets and which is also easy to implement in a given environment. This approach conceals the internal complexity of federation and offers a uniform view and access on the data.
This virtual PDM layer does not perform replication of product data, but is responsible for distribution of queries and joining the partial results to produce an overall result on the basis of the distribution model. A precondition of this concept is the mapping of the different data models and access interfaces of the individual PDM systems to form a uniform data model and a uniform access interface. The PDTnet Schema has been identified as a promising foundation for a neutral data model. The schema has been jointly developed by important companies in the German automotive industry and successfully used in various integration scenarios.
In order to provide an efficient access interface to connect distributed modules at service level, an efficient Java binding for the XML-based PDTnet interface has been developed. Some foundation modules that can be configured to federate arbitrary PDM systems use this. This paper not only presents the technical concept but also initial results of a pilot project carried out at a German OEM. This article describes concepts for and the realization of a federation of PDM systems. The federation supports not only the consolidation of product data within an enterprise but also the implementation of e-collaboration.
In this context, a federation of PDM systems refers to the virtual unification of product data that belongs together logically but which is distributed physically over a number of different systems. A typical example of the distribution of product data within an enterprise is when BoM for a product is located on another system. However, there is also substantial application potential for the federation in cross-enterprise product development.
Zielsetzung dieses Beitrages ist es, das Konzept des Collaborative Engineering darzustellen und durch die Idee der Communities, die sich als neue Organisationsform von Benutzern elektronischer Kommunikationsmedien entwickelt haben, zu erweitern. The crucial dilemma is the kind of data handled in both systems: CAD systems on the one hand operate on semantically rich data, where assemblies, parts, features or topological entities can be created and modified.
VR systems, on the other hand, mainly operate on dumb triangles. The first step in this direction is the identification and evaluation of interfaces. The interface not only allows read access to tessellated data, topology and features; it also supports modification of data - especially design features. The resulting application can be used to visualize arbitrary MD models in an immersive VR environment and interact with the design features of the models. The prototype demonstrates the feasibility of this flexible and integrative approach, where a commercial CAD system is linked to a VR environment.
Even though the complexity of the models that can be handled in real-time is quite limited in this prototype, the evaluation identifies a high potential of the CAD Services interface. Based on this work, improvements to the interface can be formulated to overcome current limitations of the OMG specification.
Dabei spielt der gemeinsame Zugriff auf das verteilt verwaltete Produktmodell eine wesentliche Rolle. Der Autor entwickelt hierzu ein Konzept, bei dem die Integration von Telekooperationsfunktionen in bestehende Systeme im Mittelpunkt steht. Application Service Providing ASP is a novel and promising approach for the distribution of software. Changing the philosophy from software as a material good e. CD-ROM to software as a service can result in a number of benefits for the software vendor reduced time to customer, development of new markets etc.
In the engineering domain, however, we find several ancillary conditions that inhibit an ASP boom just as in other areas such as customer relationship management. The tight integration of various applications CAD, CAE, PDM in the design process and the importance of high-end graphical presentation and interaction are just two of the important requirements that must be taken into account.
The first part of the paper examines technological, economic and psychological factors that influence the ASP decision, as well as presenting the actual market situation and looking at the future of engineering ASP. In the second half, we present a technical concept that can overcome various problems that arise when using today's ASP technology.
We also provide a roadmap for further research in this area and identify promising technologies for deployment, communication and integration. Auch die aktuellen Standardisierungsbestrebungen auf Ebene der Technologie z. Leitprojekt integrierte Virtuelle Produktentstehung - Abschlussbericht Juni Ein wesentliches Kennzeichen ist der hohe Integrationsgrad, der sowohl auf die Werkzeuge innerhalb einer Phase z. Relying on standards is an adequate solution for solving integration problems and saving on investment in software or hardware.
There are good opportunities for exchanging standardized components for pieces from another vendor with a justifiable amount of time and money. For the engineering domain, there is a bundle of standards available from the Manufacturing Domain Task Force, which address PDM access, transport of process data and a standard interface to CAD systems.
This paper gives an overview of the standardization process, as well as presenting the current status of the relevant specifications and looking at future activities. We discuss the functional coverage of both standards, as well as implementation aspects for the interface and interoperability issues relating to specific integration tasks.
The paper concludes with an assessment of the practical relevance of the OMG Standards and an overview of future work.
Dobermann, Falk; Lukas, Uwe von. This article describes the current status of the m4CAD project. The project deals with application areas of the MPEG-4 standard in the engineering domain. Following a brief overview of the standard, different scenarios are presented, including CAD conferencing, Application Service Providing and multimedia product catalogues.
Innovation - Konstruktion - Berechnung. PDM und tauschen so implizit Informationen aus. Faust, Rasmus; Lukas, Uwe von. The Path to Electronic Business. Proceedings of the ECEC The increasing need for cross enterprise communication for engineering teams can not be fulfilled by a single tool. The collaboration must at least be supported by two complementary concepts: Sharing resources data and services on the one hand and explicit tools for communication and coordination on the other hand.
This paper presents results from iViP project. On top of CORBA, the vertical market services of the OMG and the iViP framework, we specified several services to explicitly enable cross enterprise collaboration in heterogeneous environments. After presenting the overall approach, this paper focuses on two important branches: The iViP-Conference service as a bracket to arbitrary synchronous collaboration tools and iViP-Software on Demand, an enabling service for accessing iViP services at remote sites. Some remarks on the general security concepts of iViP and additional experiences on using CORBA in this application stress the practical perspective of this paper.
Leitprojekt integrierte Virtuelle Produktentstehung - Fortschrittsbericht April Weiterhin werden Details zu einer prototypischen Implementierung dieser Konzepte und Methoden beschrieben. Basierend auf einer Befragung zur Infrastruktur, zur aktuellen Nutzung und den Potentialen von Telekooperationssystemen bei den beteiligten Anwendern wurde ein umfassendes Konzept entwickelt.
Kennzeichnend ist der hohe Integrationsgrad auf verschiedenen Ebenen. Neu entwickelte Kommunikationswerkzeuge umfassen insbesondere ein Whiteboard und Dienste zur Kopplung von iViP-Applikationen nach dem replizierten Ansatz. Concurrent and distributed engineering are challenging concepts for reducing the time-to-market and increasing the competitiveness of new products in a global market.
The main idea of the project is the continuous virtualization of the product realization process in all its phases. It comprises the initial planning, design, testing and the manufacturing approach. The project aims at developing an integrated platform that supports all stages of the product realization cycle. This paper will give a short introduction to the concepts of cross enterprise collaboration in iViP. The acceptance of communication and collaboration tools and the potential for advanced CSCW Computer Supported Cooperative Work systems have been analyzed on the basis of a detailed questionnaire.
The results have been used to develop a in two main areas: Secondly, there are tools for collaboration and mainly synchronous communication. The iViP-Connect service is a representative of this group. This service is intended to connect two or more instances of an iViP application in a tele-conference.
Using the Internet for searching and accessing software components "on Demand" will be a future market in the context of E-Business. By applying innovative approaches for modular and distributed software systems, we now can make this vision happen. After giving a short introduction into the topics, the paper presents a reference model for classifying various technical solutions -concentrating on computer graphics applications.
This classification is used to describe the state of the art in online software distribution. It is followed by a research agenda - topics to be solved in order to have a complete framework for Software on Demand. The authors' concrete steps for implementing the frame-work are presented. The second part of the paper outlines the benefits for the different groups involved in this scenario: A case study of a small soft-ware company, starting to apply this technology will underline the practical focus of this paper. Lukas, Uwe von ; Runge, Thomas. Former and ongoing research projects aim for applying groupware technologies to this important business sector.
The focus lies on tools that are easy to use for the engineers and affordable even for small and medium sized enterprises. This implies an approach with minimal bandwidth requirements.