[Radiologic diagnostics of the gall bladder and bile ducts-part 1 : Imaging techniques-normal variants and congenital disorders-cholelithiasis]. / Radiologische Diagnostik der Gallenblase und der Gallenwege ­ Teil 1 : Bildgebende Verfahren ­ Normvarianten und Fehlbildungen ­ Gallensteinleiden.

Upper abdominal pain, icterus and cholestasis are the main symptoms leading to evaluation of the biliary tract. Since the advent of contrast-enhanced ultrasound techniques the accuracy of bile duct imaging has significantly improved. This is also true for computed tomography using isotropic secondary reconstructions as well as magnetic resonance imaging (MRI) including MR cholangiography (MRC), classically and after iv injection of hepatobiliary contrast agent. Diffusion-weighted imaging sequences have a recently proven ability for improving biliary tract imaging. These technical improvements provide the depiction of the non-dilated biliary tract system in diagnostic quality. Therefore, normal variants and congenital disorders of biliary tract anatomy are delineated as well as insights into the postoperative situs and complications related to surgery. Cholelithiasis is the most frequent disease of the gall bladder and biliary tract. Together with related complications, in the majority of cases it is also the reason for bile duct inflammation. Due to the immediate need for treatment special care has to be taken for hydrops of the gall bladder.

[Radiologic diagnosis of the gallbladder and bile ducts - part 2 : Acute and chronic cholecystitis, primary sclerosing cholangitis (PSC), benign and malignant masses of the biliary system]. / Radiologische Diagnostik der Gallenblase und der Gallenwege ­ Teil 2 : Akute und chronische Cholezystitis, primär sklerosierende Cholangitis, benigne und maligne Tumoren des Gallenwegsystems.

Upper abdominal pain, icterus and cholestasis are the symptoms leading to evaluation of the biliary tract. Together with its complications biliary stone disease is the main reason for inflammation of the biliary system. A distinction is made between acute and chronic variants. In chronic bile duct inflammation primary sclerosing cholangitis (PSC), primary biliary cirrhosis (PBC) and more recently IgG4-associated sclerosing cholangitis are of particular importance. Besides benign and tumor-like-lesions, malignant entities as gallbladder carcinoma and cholangiocarcinoma (CCC) in its three locations have to be mentioned. Despite all recent improvements, specificity of bile-tract imaging still remains limited, especially regarding malignant masses. Therefore the final diagnosis is made in many cases by histological analysis.

Prediction of response to preoperative chemotherapy in adenocarcinomas of the esophagogastric junction by metabolic imaging.

PURPOSE: Preoperative chemotherapy in patients with gastroesophageal cancer is hampered by the lack of reliable predictors of tumor response. This study evaluates whether positron emission tomography (PET) using fluorine-18 fluorodeoxyglucose (FDG) may predict response early in the course of therapy. PATIENTS AND METHODS: Forty consecutive patients with locally advanced adenocarcinomas of the esophagogastric junction were studied by FDG-PET at baseline and 14 days after initiation of cisplatin-based polychemotherapy. Clinical response (reduction of tumor length and wall thickness by > 50%) was evaluated after 3 months of therapy using endoscopy and standard imaging techniques. Patients with potentially resectable tumors underwent surgery, and tumor regression was assessed histopathologically. RESULTS: The reduction of tumor FDG uptake (mean +/- 1 SD) after 14 days of therapy was significantly different between responding (-54% +/- 17%) and nonresponding tumors (-15% +/- 21%). Optimal differentiation was achieved by a cutoff value of 35% reduction of initial FDG uptake. Applying this cutoff value as a criterion for a metabolic response predicted clinical response with a sensitivity and specificity of 93% (14 of 15 patients) and 95% (21 of 22), respectively. Histopathologically complete or subtotal tumor regression was achieved in 53% (eight of 15) of the patients with a metabolic response but only in 5% (one of 22) of the patients without a metabolic response. Patients without a metabolic response were also characterized by significantly shorter time to progression/recurrence (P =.01) and shorter overall survival (P =.04). CONCLUSION: PET imaging may differentiate responding and nonresponding tumors early in the course of therapy. By avoiding ineffective and potentially harmful treatment, this may markedly facilitate the use of preoperative therapy, especially in patients with potentially resectable tumors.

Adenocarcinoma of the gastro-esophageal junction: CT for monitoring during neoadjuvant chemotherapy.

OBJECTIVE: A clinical study was performed to assess the diagnostic value of spiral CT for evaluation of response during neoadjuvant chemotherapy (CTx) in patients with adenocarcinoma of the gastro-esophageal-junction (GEJ). Results were compared to those of endoscopy. METHODS AND MATERIAL: Twenty-five patients with histologically proven adenocarcinoma of the GEJ scheduled to undergo neoadjuvant CTx were studied. Before CT examination, 1200 ml of a vanilla flavoured paraffin emulsion were applied orally to the fasting patients and 40 mg BuscopanR or 2 mg glucagon were injected i.v. for hypotonia. Iodine (100 ml) was injected automatically (3 ml/s) and the CT scan was started 10 s after complete administration of CM. For response evaluation to CTx, four standardized parameters were measured by two experienced, blinded radiologists. The results were categorized according to the WHO classification of 1981 and compared to those of endoscopy. RESULTS: In 24 of 25 patients endoscopic and computed tomographic response evaluation showed a close correlation (r = 0.96). CONCLUSION: Spiral CT with negative oral contrast agent is a suitable technique for monitoring of GEJ masses. In combination with standardized metric parameters it offers a quantitative response evaluation in patients with GEJ masses during neoadjuvant CTx.

[CT arterioportography in the spiral technic for the demonstration of liver metastases]. / CT-Arterioportographie in Spiraltechnik zum Nachweis von Lebermetastasen.

CT arterioportography using indirect portal venous application of contrast media is the most sensitive preoperative diagnostic technique for detection of liver metastases. Spiral CT allows continuous examination of the liver (no gap) during a single breathhold. Due to short measurement times an optimized vessel and tissue contrast can be achieved during the portal venous phase. Compared with intraoperative ultrasonography CTAP using spiral CT offers similar sensitivity (96%) in the detection of liver metastases and thus emerges as an important technique for diagnosis and follow-up of liver metastases.

[Role of i.v. cholangiography and ultrasonography in preoperative diagnosis before laparoscopic cholecystectomy]. / Die Rolle der i.v. Cholangiographie und der Sonographie in der präoperativen Diagnostik vor laparoskopischer Cholezystektomie.

In a prospective clinical study the relevance of i.v. cholangiography and ultrasonography for preoperative diagnosis before laparoscopic cholecystectomy was assessed. Imaging of the common bile duct was realized successfully via i.v. cholangiography in 96.3% of all patients. Compared with ERCP, i.v. cholangiography diagnosis proved correct in 91.6% of all cases with pathological depiction of the common bile duct. Ultrasonography offered a sensitivity of 97.8% for assessing the common bile duct diameter. However, the distinction between intraductal concrements and artifacts caused by air superposition may be difficult. I.v. cholangiography is the most sensitive and easy to realize diagnostic technique to identify concrements in the common bile duct. The results of this study indicate that a combined strategy of i.v. cholangiography and ultrasonography may replace ERCP for preoperative diagnosis before laparoscopic cholecystectomy, if there is a sufficient depiction of the common bile duct and without concrements in it.

[Functional MR-pancreatography with secretin. A comparison of imaging quality and diagnostic value]. / Funktionelle MR-Pankreatikographie mit Sekretin--Intraindividueller Vergleich von Abbildungsqualität und Diagnoserelevanz.

PURPOSE: The aim of the present study was to assess imaging improvement and diagnostic value of secretin stimulated MR-pancreatography (MRP) compared to conventional MRP. MATERIALS AND METHODS: 50 patients were studied with a 1.0 T system using a single-shot-TSE sequence (RARE). Imaging quality and diameter of the different parts of the pancreatic tract and diagnoses were monitored before and after secretin. RESULTS: The visualization of the normal main pancreatic duct (MPD) was improved significantly in head, body and tail. Side branches were not depicted at all. Even in chronic pancreatitis a significant improvement of imaging quality could be observed, but only in patients without duct dilation before secretin. In advanced disease with duct dilation, secretin stimulation provided no further diagnostic improvement. CONCLUSIONS: In conclusion, secretin increases the diagnostic value of MRP especially in patients with normal or non-dilated native MPD and may help to avoid unnecessary invasive procedures such as ERCP.

[Spiral CT in aortic aneurysms. 2D and 3D reconstructions and CT angiography]. / Spiral-CT bei Aortenaneurysmen. 2D- und 3D-Rekonstruktionen, CT-Angiographie.

Spiral CT was performed in 8 normals and 40 patients with alterations of the large thoracic and abdominal vessels. It proved to be the ideal basis for 2D and 3D reconstructions. In 2D reconstruction the topographic aspects of aortic aneurysms were displayed better compared to the axial scans. In 3D reconstruction the segmentation of small vessels, and vessels running parallel to the scan plane showed problems. Stenoses were displayed unsatisfactory. In patients with aortic aneurysms 3D reconstruction showed well the location and dimension of the aneurysm as well as its position to branching arteries and the intraarterial thrombus. In case of dissecting aneurysms the true and the false lumen could clearly be distinguished. Colour-coded 3D reconstruction proved to be valuable to illustrate topographic information that could be detected only with difficulty on examining the original axial scan.

[The value of computed tomography in the diagnosis of the local and lymph node recurrences of head and neck tumors]. / Wertigkeit der Computertomographie bei der Diagnose von Lokal- und Lymphknotenrezidiven von Kopf-Hals-Tumoren.

544 CT studies of 231 patients were evaluated retrospectively to assess the role of CT in posttherapeutic monitoring of patients with head and neck tumours. CT (80%) was inferior to clinical evaluation (87%) in diagnosing recurrent malignancy due to a lack of specificity (76 vs. 92%). With CT small recurrencies were missed. Occasionally evaluation of the oral cavity was impaired by metal artifacts (dental fillings). However with larger recurrent tumours, CT offered important additional information regarding extent, infiltration of deeper compartments and bony destruction in 51% of the cases. CT (95%) was superior to clinical evaluation (80%) in diagnosing recurrent lymph node metastases. A baseline CT study at about 6-8 weeks after the end of therapy is of great importance for follow-up studies.

[MRI of the knee joint: first results of a comparison of 0,2-T specialized system and 1,5-T high field strength magnet]. / MRT des Kniegelenks: Erste Ergebnisse eines Vergleichs von 0,2-T-Spezialsystem mit 1,5-T-Hochfeldmagnet.

PURPOSE: Diagnostic accuracy and image quality of a specialised system for MR examinations of peripheral joints were evaluated. MATERIALS AND METHODS: 20 patients with acute or chronic injuries of the knee were examined using a low-field MR system (0.2 T). For comparison, all patients were also studied with a 1.5 T high field strength magnet and all diagnoses were correlated with arthroscopic findings. RESULTS: We found compatible diagnostic accuracies (cruciate ligaments 90%, menisci 75-90%) and good image quality ratings for the low field system ("good" and "excellent" image quality in 83% of cases). CONCLUSION: The low-field MR-system offers low-cost MR examinations of peripheral joints with good image quality and reliable diagnostic information.

[High-degree bilateral carotid stenoses]. / Hochgradige bilaterale Karotis-Stenosen.

The indication for carotid endarterectomy in patients with unilateral stenotic lesions as well as the operative risk in patients with bilateral disease is still controversial among experts. We performed a retrospective analysis in our patients with bilateral carotid endarterectomy. 578 patients underwent carotid endarterectomy at our institution from 1986-1992: 54 patients (9.3%) had bilateral carotid disease. 30% of these patients were asymptomatic and 16% had symptoms from both sides. Surgical results concerning the optimal restoration of blood supply (75%) and the occurrence of recurrent stenosis (8%) were comparable for patients with unilateral and bilateral carotid endarterectomy. On the contrary, in patients with bilateral carotid disease, both the operative morbidity (2.8%) and mortality (1.8%) were increased as compared to the total study population (1.9% and 0.45% resp.). Carotid endarterectomy is very effective in preventing stroke especially in patients with multiple vessel disease as compared to the natural history of these lesions.

Severe bilateral carotid stenosis.

An analysis of the relevant data from the Veterans Affairs Cooperative Study Group in asymptomatic patients, showed that 26 of the 32 ipsilateral strokes occurred during the first two years of clinical follow-up. Furthermore, as observed in the medical group, half the neurologic outcome events were strokes and were not preceded by transient ischemic attacks. In the North American Symptomatic Carotid Endarterectomy Trial over a 2-year period, 45 percent of those with occlusion had a stroke compared to 15 percent in the surgical group. These data dispel the traditionally held view that patients with severe contralateral disease should not be subjected to surgery. However, the referral of patients to centers capable of low rates of surgical complications is essential in a plan that includes carotid endarterectomy with optimal medical management.