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Photon-counting detector (PCD)-CT is expected to have a substantial impact on oncologic abdominal imaging. We compared subjective and objective image quality between PCD-CT and conventional energy-integrating detector (EID-)CT arterial phase abdominal scans.This study included 84 patients undergoing both types of abdominal CT. EID-CT scans were acquired with a tube voltage of 100 kVp. With PCD-CT, acquired with 120-kVp, we reconstructed polychromatic T3D images and virtual monoenergetic images (VMIs) in 10-keV intervals from 40 to 90 keV. Quantitative image analysis included noise and contrast-to-noise ratio (CNR) of hepatic vessels, kidney cortex, and hypervascular liver lesions to liver parenchyma. Three raters used a 5-point Likert scale for qualitative image analysis of image noise and contrast, lesion conspicuity, and overall image quality. Radiation dose exposure (CT dose index) was compared between the two CT types.Mean CT dose index and effective dose were respectively 18 % and 26 % lower with PCD-CT versus EID-CT. Compared with EID-CT, CNRs of kidney cortex and vessel to liver parenchyma were significantly higher in PCD-CT VMIs at energies ≤ 60 keV and in polychromatic T3D images (p 0.004). Overall image quality of PCD-CT VMIs at 50 and 60 keV was rated as significantly better (p 0.01) than the EID-CT images (inter-reader agreement alpha = 0.80). Lesion conspicuity was significantly better in low-keV VMIs (p 0.03) and worse in 70-keV VMIs.With low-keV VMI, PCD-CT yields significantly improved objective and subjective quality of arterial phase oncological imaging compared with EID-CT. This advantage may translate into higher diagnostic confidence and lower radiation dose protocols.

Anamnese: Bei einem 25jahrigen Patienten war vor 6 Jahren eine schwere Colitis ulcerosa diagnostiziert worden. Im selben Jahr muste er wegen eines mechanischen Ileus laparotomiert werden. Seitdem waren unter einer Sulfasalazin-Therapie keine entzundlichen Schube aufgetreten. Wegen bekannter ausgepragter Pseudopolypenbildung im gesamten Kolon wurde eine endoskopische Kontrolluntersuchung durchgefuhrt. Untersuchungen und Befunde: Das Endoskop wurde glatt eingefuhrt, die Untersuchung verlief ohne Pramedikation schmerzfrei. Das Kolon wurde bis zum Zokalpol eingesehen. Beim Zuruckziehen wurden Biopsien entnommen. Plotzlich bemerkte der Patient ein starkes Anschwellen des Skrotums. Die Untersuchung wurde sofort beendet. Beim Zuruckziehen des Koloskopes konnten in den distalen Abschnitten des Kolons keine Wandlasionen beobachtet werden. Kurze Zeit danach hatte sich uber der rechten Abdomen- und Thoraxseite bis an den Hals ein Hautemphysem entwickelt. Der Patient konnte seine eigene Stimme nur noch gedampft wahrnehmen. Das Abdomen war klinisch unauffallig. Rontgenologisch wurden ein beiderseitiges Pneumoretroperitoneum, ein Mediastinalemphysem und ein Pneumothorax nachgewiesen. Therapie und Verlauf: Der Patient wurde 4 Tage lang parenteral ernahrt und prophylaktisch mit Amoxicillin, Clavulansaure und Metronidazol behandelt. Die Luft wurde resorbiert, und der Patient wurde nach insgesamt 7 Tagen beschwerdefrei entlassen. Folgerung: Im Gegensatz zur intraperitonealen Perforation, die meist von einem akuten Krankheitsbild mit Peritonitis gefolgt ist und meist sofort chirurgisch behandelt werden mus, ist der Verlauf der seltenen retroperitonealen Perforation in der Regel symptomarm und benigne und kann konservativ behandelt werden. History: Severe ulcerative colitis had been diagnosed in a 25-year-old man six years ago. That same year he underwent laparoscopy for mechanical ileus. Since then he has been on a maintenance dose of sulphasalazine without any further symptoms. Because of a known pseudopolyposis coli, repeat coloscopy was performed. Examinations and findings: The endoscope was smoothly introduced and the examination was without pain. No premedication had been given. A biopsy was obtained during withdrawal of the endoscope. Suddenly the patient noticed marked scrotal swelling. The examination was terminated abruptly. No lesions of the wall of the distal colon were seen when the endoscope was pulled out immediately. Quickly, cutaneous emphysema developed over the right side of the abdomen and thorax up to the neck. The patient could no more properly heer his own voice. Radiology demonstrated bilateral pneumoretroperitoneum, mediastinal emphysema and pneumothorax. Treatment and course: The patient was put on parenteral nutrition for 4 days and prophylactically received amoxycillin, calvulanic acid and metronidazole. The air was gradually absorbed and the patient discharged symptom-free after 7 days. Conclusion: In contrast to intraperitoneal Perforation, which usually causes acute symptoms of peritonitis and requires urgent surgical treatment, the course of the much rarer retroperitoneal Perforation is more benign with few symptoms and can be managed conservatively.

Purpose: To compare MRI findings and histological plasmacellular infiltration of the bone marrow in patients with multiple myeloma (MM). Material and Methods: Twenty-four patients with different stages of MM underwent 1.5T MRI of the pelvic bone before iliac crest punch biopsy. Precontrast T1wSE and STIR and postcontrast (Gd-DTPA) T1wSE-fatsat were acquired using axial slices. Immediately after the biopsy, T1 wSE was repeated to locate the biopsy canal. The corresponding region in the examination before punch biopsy was assessed for bone marrow involvement using a three-point score (0: negative, 1: suspect, 2: definite). Results: Two patients were not included because the location of the biopsy canal was unclear. Of 7 patients without histological plasmacellular infiltration, MRI was false positive in one case (suspect). Of 15 patients with histological infiltration, MRI was positive in 10 cases (4 suspect, 6 definite). The T1wSE was positive in 9 cases, STIR in 8 cases, and postcontrast T1wSE-fatsat in 7 cases. In 10 of the 15 patients, the infiltration was histologically graded as low (5-20% of bone marrow). In this group, MRI was only positive in 5 cases (3 suspect, 2 definite). Of five patients with the infiltration histologically graded as high (> 20% of bone marrow), MRI was positive in all cases (1 suspect, 4 definite). Conclusion: Only advanced bone marrow infiltration in MM can be reliably detected by MRI. None of the used sequences proved to be significantly superior or inferior.

AIM The initial diagnostics of acute diverticulitis of the sigmoid should render the correct diagnosis as well as assisting in the decision on the options of conservative or surgical treatment by ruling out or demonstrating complications. At present, sonography or computed tomography (CT) are the two competing diagnostic options. This study was designed to demonstrate that sonography could be used as the method of choice. METHOD 63 patients with clinical suspicion of acute diverticulitis of the sigmoid were examined initially by sonography or CT in a prospective study. RESULTS Sonography and CT showed a 97 % sensitivity and specificity for reaching the accurate and clinically plausible diagnosis. As to the demonstration of complications of the disease, sensitivity and specificity were comparably high for both diagnostic methods. CONCLUSIONS Sonography can compete with the more complex CT examination and therefore represents the recommended primary diagnostic procedure.

PURPOSE To quantify changes of bone marrow microcirculation in multiple myeloma (MM) using contrast enhanced dynamic MRI (dMRI) during thalidomide as antiangiogenic monotherapy or in combination with chemotherapy (cyclophosphamide, etoposide, dexamethasone). MATERIALS AND METHODS The study includes 63 patients with refractory or relapsed MM, who underwent dMRI with high temporal resolution (T1w-turboFLASH) of the lumbar spine before and following treatment. The contrast uptake was quantified using a two compartment model with the output parameters amplitude and k (ep) (exchange rate constant). The evaluation considered the initial dMRI finding (pathological or non-pathological) and the clinical therapeutic response (response or no response). RESULTS During monotherapy with thalidomide (n = 38), no significant changes of the dMRI parameters were found, even when considering the initial dMRI finding (positive n = 22) and the therapeutic response (responder n = 14). The combination with chemotherapy (n = 25) had a significant reduction of k (ep) (p = 0.01) in 18 patients with positive initial dMRI finding and therapeutic response. Reduction of the amplitude was seen in most cases, but in the end without any significance (p = 0.09). CONCLUSION dMRI can quantify significant changes of bone marrow microcirculation solely during treatment with thalidomide combined with chemotherapy, not with thalidomide alone.

Komplexe supraaortale Gefasbefunde bedurfen eines individuellen Therapiemanagements. Wir berichten uber einen 74-jahrigen Patienten, bei dem 1980 bei einem supraaortalen komplexen Verschlussprozess ein Subklavia-Subklavia-Bypass implantiert worden war und der sich jetzt mit einem Aneurysma in Bypassmitte, einer Abgangsstenose der linken A. subclavia, einem Verschluss des Truncus brachiocephalicus und der linken A. carotis communis vorstellte. Wahrend des stationaren Aufenthalts kam es zum spontanen Bypassverschluss mit kompensierter Ischamie. Primar wurde die linke A. subclavia mittels PTA und Stent versorgt, dann erfolgte die Neuanlage des Subklavia-Subklavia-Bypasses. Neurologie und Bildgebung waren postoperativ regelgerecht. Komplexe supraaortale Gefasbefunde konnen in Kombination interventioneller und offener Verfahren erfolgreich behandelt werden.

Radiofrequenzchirurgische Techniken erlangen aufgrund ihrer minimal-invasiven Eigenschaften zunehmende Bedeutung. Die temperaturkontrollierte Technik hat sich in der Therapie schlafbezogener Atmungsstorungen etabliert. Trotz des zunehmenden Einsatzes gibt es jedoch kaum Daten zu den induzierten Effekten in vivo. Sechs Patienten wurden einer radiofrequenzchirurgischen Behandlung des Zungengrundes unterzogen. Die kernspintomographischen Untersuchungen mittels Inversion-recovery-Technik erfolgten 4–6, 8–10 sowie 24 h postoperativ. Zu allen Zeitpunkten liesen sich die erzeugten Gewebslasionen gut darstellen. In allen Schichtungen imponierte eine ovalare hypointense Struktur. Um die Lasion zeigte sich ein hyperintenses Areal. Im zeitlichen Verlauf imponiert eine geringfugige Reduktion der Lasionsgrose. Mit der Kernspintomographie steht ein potentes bildgebendes Verfahren zur Verfugung, mit dessen Hilfe sich radiofrequenzchirurgisch erzeugte Gewebslasionen hervorragend darstellen und die technischen Einstellungen dieser Technik zukunftig weiter optimieren lassen.

Bei klinischem Verdacht auf eine akute mesenteriale Ischamie steht die Sonographie des Abdomens mit Duplexsonographie der Mesenterialgefase am Beginn der bildgebenden Diagnostik.Der direkte Nachweis des Gefasverschlusses gelingt auch erfahrenen Untersuchern nur mit geringer Sensitivitat, erlaubt aber im positiven Fall die Indikationsstellung zur Operation unter Verzicht auf jede weitere Diagnostik. Die Befunde auf Rontgenubersichtsaufnahmen sind unspezifisch. Das Verfahren dient vorwiegend dem Nachweis oder Ausschluss wichtiger Differenzialdiagnosen und gestattet nur in Spatfallen die direkte Diagnose der mesenterialen Ischamie.Die Spiral-CT (idealerweise mit Multidetektortechnik) ermoglicht eine zuverlassige morphologische Beurteilung der mesenterialen Gefase,der Darmwand und reaktiver Veranderungen in der Umgebung und bietet damit die Grundlage fur eine pathologisch-anatomisch begrundete Diagnostik der mesenterialen Ischamie.Nahezu alle wichtigen Differenzialdiagnosen zur mesenterialen Ischamie konnen durch die Spiral-CT nachgewiesen oder ausgeschlossen werden.Die Magnetresonanztomographie (MRT) ist mit der CT-Diagnostik vergleichbar, wegen des hoheren Aufwands und der geringeren Verfugbarkeit spielt sie in der Notfalldiagnostik aber (noch) keine entscheidende Rolle.Die Katheterangiographie bleibt Methode der Wahl zur Beurteilung des mesenterialen Gefassystems,wenn ein Spiral-CT nicht zur Verfugung steht.

Ziel der Studie war es, eine Methode zur minimal-invasiven Reposition und Aufrichtung frakturierter Wirbelkorper zu entwickeln. Methoden. 7 humane Lendenwirbelkorper wurden unter axialer Last bis zur Frakturgrenze belastet und die Kompressionscharakteristik erfasst. Anschliesend erfolgte Bildwandler-gesteuert die transpedikulare Einfuhrung zweier mit Stents armierter Ballonkatheter, welche unter BV-Kontrolle bis zum Erreichen der ursprunglichen Wirbelkorperform mit Kontrastmittel dilatiert wurden. Danach erfolgte die Entleerung der Ballons und deren Entfernung. Der entstehende Hohlraum wurde ebenfalls transpedikular mit injizierbarem Kalziumphosphat gefullt. Nach Ausharten wurde die Kompressionstestung wiederholt. Die Wirbelkorper wurden mittels Dunnschicht-CT vor und nach der Destruktion sowie nach der Expansion vermessen. Ergebnisse: 1. Durch die Ballondilatation wurde eine nahezu komplette Wiederherstellung der ursprunglichen Hohe der Wirbel erreicht. 2. Ein Kollaps des Stents nach Entfernung des Ballons wurde nicht beobachtet. 3. Durch die Augmentation mit injizierbarem Ca-Phosphat konnte die Belastbarkeit des Wirbels wiederhergestellt werden. Schlussfolgerung: Mit dem Vertebral Body Stenting steht eine Methode zur Versorgung osteoporotischer und traumatischer Wirbelfrakturen zur Verfugung, die eine minimal invasive Wiederherstellung der Wirbelform ermoglicht und die Entstehung einer posttraumatischen Kyphose verhindern konnte.

Die Teleradiologie bietet sehr viele Moglichkeiten zur Qualitatssicherung und -verbesserung in der Medizin an. Das Spektrum reicht von elektronischen Konsultationen in Notfallen oder elektiven Spezialfragen sowie Doppelbefundung uber neue Modelle kooperativen Arbeitens und der Verwirklichung von Netzstrukturen bis zur technischen Qualitatssicherung und der Integration in institutionenubergreifende, patientenkontrollierte Gesundheitsakten. Regionale Teleradiologienetze mit Serverkonzepten bilden die entstehenden Anforderungen von technischer und organisatorischer Seite ab. Die steigende Mobilitat mit kleineren Untersuchungsgeraten und zusatzlich die erhohte Erreichbarkeit bei Experten mit Minibefundungssystemen in Kombination mit dem Einsatz wissensbasierter Systeme in Referenzdatenbanken und der computerunterstutzten Diagnose (CAD) verandern die radiologische Welt von morgen. Dabei sind, wie in der neuen Rontgenverordnung vorgesehen, qualitatssichernde Vorgaben fur die Teleradiologie selbst zu erstellen, beispielsweise um eine unnotige Strahlenexposition oder eine Gefahrdung der Arzt-Patienten-Beziehung zu verhindern.

Legal prerequisites have substantial influence on the development of teleradiology. At an expert meeting (Mannheim, 8.6.2001) a proposal for a teleradiology article in the new German x-ray ordinance has been set up. An exception of the demand for a doctor trained in radiation protection at the point of examination shall be established for emergency cases. To realize the intended improvement of patient care measurements for quality assurance concerning the medical personnel and processes are necessary. Along with other current developments the basis of secure regional teleradiology networks is now built up.

Six cases of granulocytic sarcoma are presented. A mediastinal chloroma and a tumor of the submandibular gland were observed with two patients as single sign of acute myeloic leukaemia. In one patient a chloroma appeared as first manifestation of acute myeloic leukaemia. Two patients exhibited the tumor as first symptom of a blastic crisis of chronic myelogenous leukaemia (femoral bone, lumbar spine). The sixth patient with a myelodyplastic syndrom showed a chloroma of the breast. Various radiological procedures were applied including plain radiography, MRT, CT and mammography. The results are compared with literature. Principles of therapy were supplemented.

Bei einem Patienten mit primarem Hyperparathyreoidismus wurde ein zystisches Nebenschilddrusenadenom praoperativ durch ultraschallgesteuerte Feinnadelpunktion und den Nachweis einer erhohten Parathormonkonzentration im Aspirat diagnostiziert. In one patient with primary hyperparathyroidism, a cystic parathyroid adenoma was diagnosed pre-operatively by ultrasound-guided fine-needle aspiration biopsy and the detection of an elevated parathyroid hormone concentration in the aspirate.

To calculate canal compromise and decrease of midsagittal diameter caused by retropulsion of fragments into the spinal canal we analyzed the pre- and postoperative computed tomographies of 32 patients with unstable thoracolumbar burst fractures treated by USS (universal spine system). Our intention was to examine the efficiency of ultrasound guided repositioning of the dispaced fragments which was performed in all 32 cases. We found a clear postoperative enlargement of canal area (ASP preoperatively 55 %, postop. 80 %) and midsagittal diameter (MSD preop. 58 %, postop. 78 %). 10 of 13 patients presented a postoperative improvement of neurological deficit, no neurological deterioration occured. Fractures with neurological deficit showed more canal compromise (52 %) and less midsagittal diameter (MSD compromise 51 %) than those without (40 % or 39 %). There was no correlation between the percentage of spinal canal stenosis and the severity of neurological deficit. Below L 1 the spinal canal is greater than between Th 11 and L 1, so a more important spinal stenosis is tolerated. In case of unstable burst fractures with neurological deficit the ultrasound guided spinal fracture reposition is an effective procedure concerning the necessary improvement of spinal stenosis: an additional ventral approach for the revision of the spinal canal is unneeded. In fractures without neurologic deficit the repositioning of the displaced fragments promises an avoidance of long-term damages such as myelopathia and claudicatio spinalis.

MRI of lung airspaces using gases with MR-active nuclei ((3) He, (129) Xe, and (19) F) is an important area of research in pulmonary imaging. The volume-controlled administration of gas mixtures is important for obtaining quantitative information from MR images. State-of-the-art gas administration using plastic bags (PBs) does not allow for a precise determination of both the volume and timing of a (3) He bolus.A novel application unit (AU) was built according to the requirements of the German medical devices law. Integrated spirometers enable the monitoring of the inhaled gas flow. The device is particularly suited for hyperpolarized (HP) gases (e.g., storage and administration with minimal HP losses). The setup was tested in a clinical trial (n = 10 healthy volunteers) according to the German medicinal products law using static and dynamic ventilation HP-(3) He MRI.The required specifications for the AU were successfully realized. Compared to PB-administration, better reproducibility of gas intrapulmonary distribution was observed when using the AU for both static and dynamic ventilation imaging.The new AU meets the special requirements for HP gases, which are storage and administration with minimal losses. Our data suggest that gas AU-administration is superior to manual modes for determining the key parameters of dynamic ventilation measurements.

Radiology plays an important role in introduction and use of information technology (IT) systems in the daily clinical routine. The radiology information system (RIS) and picture archiving and communication system (PACS) are the main systems used in a digital radiology department. In this article the basic principles and functions of these systems and trends in development are described.

The aim of the present study was to evaluate the outcome of endovascular treatment of true-lumen collapse (TLC) of the downstream aorta after open surgery for acute aortic dissection type A (AADA).Retrospective, observational study with follow-up of 16 ± 7.6 months. From April 2010 to January 2012, 89 AADA-patients underwent aortic surgery. Out of these, computed tomography revealed a TLC of the downstream aorta in 13 patients (14.6%). They all received additional thoracic endovascular aortic repair (TEVAR) in consequence of malperfusion syndromes.In all 13 TLC-patients, dissection after AADA-surgery extended from the aortic arch to the abdominal aorta and malperfusion syndromes occurred. Remodeling of the true-lumen was achieved by TEVAR with complemental stent disposal in abdominal and iliac arteries in all cases. One patient died on the third postoperative day due to intracerebral hemorrhage. Another patient, who presented under severe cardiogenic shock died despite AADA-surgery and TEVAR-treatment. Thirty-day mortality was 15.4% in TLC-patients (N = 2/13). In the follow-up period, 3 patients required additional aortic stents after the emergency TEVAR procedures. After 20 weeks, a third patient died secondary to malperfusion due to false-lumen recanalization. Therefore, late mortality was 23.1%.After proximal aortic repair for AADA, early postoperative computed tomography should be demanded in all patients to exclude a TLC of the descending aorta. Mortality is still substantial in these patients despite instant TEVAR application. Thus, in case of TLC and malperfusion syndrome of the downstream aorta, TEVAR should be performed early to alleviate or even prevent ischemic injury.

Strategies for reducing radiation exposure are an important part of optimizing medical imaging and therefore a relevant quality factor in radiology. Regarding the medical radiation exposure, computed tomography has a special relevance. The use of the integrating the healthcare enterprise (IHE) radiation exposure monitoring (REM) profile is the upcoming standard for organizing and collecting exposure data in radiology. Currently most installed base devices do not support this profile generating the required digital imaging and communication in medicine (DICOM) dose structured reporting (SR). For this reason different solutions had been developed to register dose exposure measurements without having the dose SR object.Registration and analysis of dose-related parameters is required for constantly optimizing examination protocols, especially computed tomography (CT) examinations based on the latest research results in order to minimize the individual radiation dose exposure from medical imaging according to the principle as low as reasonably achievable (ALARA).

Due to increasing amounts of data in radiology methods for image compression appear both economically and technically interesting. Irreversible image compression allows markedly higher reduction of data volume in comparison with reversible compression algorithms but is, however, accompanied by a certain amount of mathematical and visual loss of information. Various national and international radiological societies have published recommendations for the use of irreversible image compression. The degree of acceptable compression varies across modalities and regions of interest.The DICOM standard supports JPEG, which achieves compression through tiling, DCT/DWT and quantization. Although mathematical loss due to rounding up errors and reduction of high frequency information occurs this results in relatively low visual degradation.It is still unclear where to implement irreversible compression in the radiological workflow as only few studies analyzed the impact of irreversible compression on specialized image postprocessing. As long as this is within the limits recommended by the German Radiological Society irreversible image compression could be implemented directly at the imaging modality as it would comply with § 28 of the roentgen act (RöV).

Die transvaskulare Plazierung endoluminaler Gefasprothesen mittels interventionell-radiologischer Methoden ist ein neues, minimal invasives Verfahren zur Therapie von Aortenaneurysmen. Wir analysierten retrospektiv die Praktikabilitat verschiedener Anasthesieverfahren, die pathophysiologischen Auswirkungen des Eingriffs und typische Risiken. Bei 19 Patienten mit Aneurysmen der infrarenalen (n=18) oder der thorakalen Aorta (n=1) wurden in 23 Eingriffen aortale Stentprothesen implantiert. Die Eingriffe erfolgten in Allgemeinanasthesie (AA: n=9), in Periduralanasthesie (PDA: n=8) oder Lokalanasthesie (LA: n=6) mit Analgosedierung. Trotz erhohten Uberwachungsaufwands in der Gruppe AA ergaben sich keine Unterschiede in folgenden Parametern: Inzidenz und Dauer intraoperativer hypertensiver, brady- oder tachykarder Phasen; Einsatz von Vasopressoren, Antihypertensiva oder Volumenersatz. Hypotensive Episoden waren bei Allgemeinanasthesien haufiger. Postoperativ zeigten alle Patienten Anstiege der Korpertemperatur sowie laborchemischer Entzundungsparameter. Vom Anasthesieverfahren abhangige Unterschiede im Verlauf der Entzundungsreaktion waren nicht erkennbar. 13 von 18 Patienten zeigten passagere arterielle Desaturationen zwischen 83% und 95%. In 3 Fallen gingen Temperaturanstiege mit kardialen Komplikationen (Tachyarrhythmien, Stenokardie) einher. Perioperative Myokardinfarkte oder Todesfalle traten nicht auf. Zur endovaskularen Therapie ausgewahlter Aortenaneurysmen sind neben der Allgemeinanasthesie auch die Regional- oder die Lokalanasthesie mit Analgosedierung praktikable, sichere Verfahren, sofern invasives Monitoring und engmaschige postoperative Uberwachung gewahrleistet sind. Die eingriffstypische abakterielle Entzundungsreaktion stellt fur kardiopulmonal vorgeschadigte Patienten ein Risiko dar.

To evaluate treatment of infrarenal abdominal aortic aneurysm (AAA) with a new endoluminal stent-graft.In 26 male patients, straight or bifurcated nitinol stents covered with woven Dacron graft material were implanted to treat eccentric saccular AAA (n = 3) or AAA involving the bifurcation and common iliac arteries (n = 23), with follow-up from 8 days to 8 1/2 months.Implantation was technically successful in all but one of the 26 (96%) patients (leak of the stent-graft for more than 3 months necessitated implantation of an additional covered stent). In seven of the 26 patients, minor residual perfusion persisted immediately after implantation, but complete thrombosis occurred within 7 days. Five procedure-related complications occurred: distal embolization (n = 2); local hematoma, which necessitated surgery (n = 1); acute hepatic failure due to gastric bleeding, in a patient with liver cirrhosis (n = 1); and stent-graft occlusion due to emboli originating from the left atrium (n = 1).Exclusion of AAA from circulation was feasible, safe, and clinically effective with the new stent-graft.

Between March 1989 and December 1992, a total of 85 pelvic exenterations were performed in the Department of Gynaecology and Obstetrics of the University of Mainz. To assess the accuracy of preoperative Magnetic Resonance Imaging (MRI) and Computer Tomography (CT) with regard to tumour localisation and spread, the results of 28 MRI and 14 CT examinations were compared with the postoperative histological findings. For this widely varying patient group that had undergone a broad range of previous treatments, MRI produced an accurate forecast in 56% of cases (CT, 36%). In 33% of the patients tested, the diagnosis based on MRI was partially correct (CT, 43%), whereas the MRI results fundamentally disagreed with the actual findings in 11% of cases (CT, 21%). We conclude that both MRI and CT are of great value in the planning of operations and for informing patients about their condition; however, in individual cases, an intraoperative quick-section diagnosis is necessary to provide details of tumour spread. If the extent of tumour spread is uncertain, the results of CT and/or MRI should not deter the surgeon from the radicality of the planned operative intervention.

In this study, the diagnostic value of renal function scintigraphy performed both without and with ACE inhibition has been evaluated using the new radiopharmaceutical 99mTc-MAG3. In cases of decompensated renal artery stenoses, the typical scan finding with this tubular excreted agent was shown to be a distinct parenchymal nuclide retention in combination with a delayed appearance of the radiotracer in the pelvic system. Using this criterion in 43 patients with suspected renovascular hypertension, sensitivity and specificity were 89 and 88%, respectively. Bilateral positive findings were non-specific; excluding them from the study, specificity increased to 100%. In renal insufficiency, captopril scans seem to be of reduced diagnostic value. Summarising our experiences, renal function scintigraphy using 99mTc-MAG3 without and with captopril was proved to be a reliable non-invasive method to detect or exclude haemodynamically relevant renal artery stenosis.

ZusammenfassungIm Rahmen der Diagnostik der renovaskulären Hypertonie hat die Nierenfunktionsszintigraphie unter Einfluß eines ACE-Hemmers als nichtinvasives Verfahren erhebliche Bedeutung erlangt. Unter Einsatz des Radiopharmazeutikums 99mTc-MAG3 wurden bei 54 Nieren mit angiographisch, klinisch und endokrinologisch gesicherter Diagnose folgende szintigraphischen Parameter isoliert auf ihre Aussagekraft zum Nachweis bzw. Ausschluß einer relevanten Nierenarterienstenose untersucht: parenchymaler Nuklidtransport, Harnabflußsituation, Nierengröße und seitengetrennte Funktionsanteile. Als typischer Befund einer dekompensierten Nierenarterienstenose erwies sich eine ausgeprägte parenchymale Nuklidretention in Kombination mit einer deutlich verzögerten Harnaktivitätsanflutung im Nierenhohlraumsystem. Im Vergleich zur rein visuellen Beurteilung der Sequenzszintigramme erbrachte die Miteinbeziehung zusätzlicher, quantitativer Kriterien im eigenen Patientenkollektiv keine diagnostischen Vorteile. Bei 43 Patienten mit klinischen Hinweisen auf eine renovaskuläre Hypertonie ergab sich mit diesen Kriterien eine Sensitivität von 89%, die Spezifität betrug 88%. Bilateral positive Befunde erwiesen sich als unspezifisch; blieben diese unberücksichtigt, erhöhte sich die Spezifität der Untersuchung auf 100%.