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Purpose: The present investigation aimed at examining changes in muscle metabolism caused by treatment of arterial occlusive disease, using dynamic 31-phosphorus methods., Method: 32 patients with arterial occlusive disease were examined in a 1.5 T apparatus with a 6 cm surface coil before and after treatment. The metabolic changes in the quadriceps muscles were visualised during a 36 s phosphorus spectrum during rest, exercise (isometric and isotonic) and during a period of recovery., Results: Vascular therapy resulted in a significant increase in the duration of both types of exercise during dynamic phosphorus spectroscopy (isometric exercise: 282 s against 199 s: p = 0.002, isotonic exercise: 575 s against 222 s; p = 5 x 10(-6). After treatment, exercise-induced changes in pH (7.00 against 6.94; p = 0.004 and 7.00 against 6.93; p = 0.02) and the ratio Pi/PCr (0.34 against 0.44; p = 0.002 and 0.36 against 0.50; p = 0.009) were significantly smaller than before therapy, using a similar amount of exercise. Recovery time of Pi/PCr (45 s against 82 s; P = 10(-5) and 42 s against 57 s; p = 0.01) and pH value (154 s against 181 s; p = 0.14 and 173 s against 214 s; p = 0.22) showed significant reduction after treatment., Conclusions: Dynamic 31-phosphorus magnetic resonance spectroscopy indicates increased mitochondrial oxidative capacity in the quadriceps muscles as evidence for increased oxygen supply to muscle tissue following vascular therapy.

Purpose: To compare the value of hydro-MRI with follow-through examinations in the follow-up of Crohn's disease., Method: 22 patients known to be suffering from Crohn's disease were examined via 1.5 T-MR system; an oral contrast examination using 1000 ml of a 2.5% mannitol solution was performed in all patients. T2-weighted TSE sequences and T1-weighted SE sequences were performed before and after the intravenous injection of Gd-DTPA. To reduce movement artifacts caused by peristalsis of the gut, intravenous injection of 40 mg Buscopan was given. The findings of hydro-MRI were compared with the follow-through examinations., Results: In the upper gastrointestinal tract, the follow-through examination showed clear advantages compared with hydro-MRI for the demonstration of inflammatory changes in the gut; Hydro-MRI was, however, somewhat more reliable in the ileum and colon. It was also more sensitive than the follow-through for the demonstration of enteric fistulae (four as compared with two cases), and in demonstration extraluminal changes (free fluid in six against zero, and inflammatory adherent loops (four against zero)). Amongst the 22 patients, hydro-MRI was equal (in 10) or better (in 8) than the follow-through examination for demonstrating the intestinal manifestations of Crohn's disease, and follow-through was better in only four., Conclusion: For follow-up of Crohn's disease, hydro-MRI is at least as good as follow-through examination, and is even preferable, because of the absence of radiation exposure of the usually young patients.

Purpose: The aim of the present investigation was to examine the metabolism of the quadriceps muscles of normal young individuals using dynamic 31phosphorus magnetic resonance spectroscopy., Methods: 22 normal individuals were examined in a 1.5T-MRT using a 6 cm surface coil. The metabolic changes in the quadriceps muscle as shown by the phosphorus spectrum were evaluated during rest, exercise (isometric and isotonic exercise) and during a 36-second period of recovery., Results: The Pi/PCr quotient rose from its resting value of 0.11 +/- 0.02 following exercise to a maximum of 0.83 +/- 0.47 (isometric) or 1.40 +/- 0.59 (isotonic) (difference p = 0.0001). Half-time recovery of Pi/PCr was 35 +/- 11 s or 31 +/- 10 s, respectively (p = 0.13). During the recovery phase Pi/PCr fell briefly but significantly below its rest value. Following an initial rise in pH, there was a continual fall. Minimum pH (6.68 +/- 0.21 and 6.53 +/- 0.27 respectively; p = 0.01) occurred in the early recovery phase. The recovery process of pH values lasted longer following isotonic than after isometric exercise (half-value recovery time 229 +/- 72 s and 146 +/- 55 s, respectively; p = 0.001)., Conclusion: Compared with isometric exercise, isotonic stress is more expensive in terms of metabolism. Dynamic 31phosphorus MRT spectroscopy can differentiate changes in muscle metabolism during different forms of exercise.

Purpose: Documentation via MRI of the healing of ruptured lateral collateral ankle ligaments after functional therapy., Patients and Methods: 35 patients with ankle sprain were examined by MRI and stress radiographs, 13 were operated afterwards, 22 patients underwent a functional conservative therapy and were examined by MRI and stress radiographs and second time after three months., Results: MRI reports were correct in 12 of 13 operated cases. After conservative therapy we did not find any disrupted ankle ligament. MRI showed intact ligaments thickened by scar., Conclusion: MRI is able to show injuries of the lateral collateral ankle ligaments and demonstrates the healing by scar after conservative therapy.

There is little experience with imaging of thyroid carcinoma tissue by somatostatin receptor scintigraphy. Our case report describes an acromegalic patient, in whom 111In pentetreotide scintigraphy did not only demonstrate a receptor-positive pituitary tumor but also visualized metastases from a papillary thyroid carcinoma which had no correlate in radioiodine scintigraphy carried out under hypothyroid conditions. The possible role of this radiopharmaceutical in dedifferentiating thyroid carcinoma is discussed for its usefulness in tumor localisation and its predictive value for the outcome of an octreotide therapy.

Aim: Examination of the distensibility of the cruciate ligaments to evaluate the tense plasty of the cruciate ligaments., Material and Method: A functional MR study was performed using a Magnetom Open (0.2 Tesla, Fa. Siemens). We measured the length and width of the anterior and posterior cruciate ligament in volunteers (n = 12), age 20-40. We examined in 4 knee positions between maximal extension and maximal flexion., Results: Using the Wilcoxon test, the statistics do not show any significant difference between the length and width of the cruciate ligaments in the monoxial movement., Conclusion: Our results may support the operative tense plasty of the cruciate ligaments although the entire complex mechanical system has not been examined.

Purpose: Improvement of pelvic MRI using peroral administration of an aqueous mannitol solution., Methods: We retrospectively evaluated magnetic resonance examinations of 72 patients with suspected or proven pelvic abnormalities: In 36 patients, no bowel marking was carried out. In further 36 patients, we performed a contrast enhancement of the bowel by oral application of 1000 ml of an aqueous mannitol solution., Results: 8/36 (22%) patients suffered from diarrhoea, nausea or meteorism as a result of mannitol application. In group 2, an excellent bowel marking of the small intestine could be obtained in 36/36 (100%) patients. Contrast enhancement of the bowel significantly improved delineation between intestinal structures and pelvic organs or pathologic lesions, respectively. In summary, bowel marking was desirable in 25/36 (69%) of group 1 and helpful in 26/36 (72%) of group 2., Conclusion: Aqueous mannitol solution is a safe bowel contrast agent and improves the diagnostic value of pelvic MRI, but in some cases delineation between marked bowel and cystic pelvic lesions may be uncertain.

The following case report describes a solitary epithelioid haemangioendothelioma of the lung as an uncommon radiomorphologic differential diagnosis of an aspergilloma. Epithelioid haemangioendotheliomas are rare low-grade malignant mesenchymal tumours that typically appear multifocally in the body.

The local alcohol concentration in the human brain was determined in 10 cases using MR spectroscopic imaging. Therefore 7 subjects with an average blood alcohol concentration of 0.8/000 were examined after oral intake of alcoholic beverages. Varying alcohol concentration was found intracranially which was recorded spectroscopically w.r.t. time. Relatively high ethanol concentrations were determined in the cerebellum as well as in the ventricular system. Contrary to this, lower concentrations were found in the regions of grey and white matter.

Two weeks to 120 months after enucleation of renal tumours the postoperative defects were correctly localized by renal computed tomography in 34 patients. Typical defect morphology was either wedge-shaped or concave. No dependence on tumour localization, tumour size, operative technique or a certain surgeon was observed. The cortical defects were smaller (mean 2.0 cm) than the original, prominent tumours (mean 3.4 cm). In small defects without tension suture of the capsule is sufficient, leading to minor defects. Larger defects were closed with a retroperitoneal or free peritoneal fat flap resulting in larger residual defects. In case of intra- or postoperative bleeding, CT could demonstrate parenchymatous or perirenal haematomas or delayed perfusion of adjacent parenchyma. In one patient a recurrent tumour was correctly diagnosed, different postoperative complications (such as abscesses) were not observed.

In a prospective study possible indications for MR arthrography of the shoulder were evaluated. 37 patients were examined before and after intraarticular administration of a 2-mmolar solution of Gd-DTPA. MR arthrography was performed if there was no joint effusion and/or an uncertain finding concerning the rotator cuff or the capsulolabral complex on plain MR images. MR arthrography leads to a better demonstration of labrum pathology in 11/22 patients and to a superior delineation of the capsuloligamentous apparatus in 20/22 cases. In 9/15 patients with impingement lesions MR arthrography allowed a differentiation of severe tendinitis from partial and small full-thickness tears of the rotator cuff. MR arthrography of the shoulder joint enhances the accuracy of MR in case of an uncertain finding on plain MR images.

We evaluated in this study the value of preoperative examinations of anal atresia with an optimised MRI strategy. 13 patients with anorectal anomalies, most of them younger than one year, underwent an MRI examination of the pelvis. 10 of these patients were operated afterwards. Compared with the situs shown by the operation the results of the MRI examination were very exact in all cases in respect of the level of atresia and the development of the striated muscle complex. Fistulas could be completely described in most cases. MRI demonstrated additional lesions in some patients which were of great importance for planning the further treatment of the patients. As a consequence MRI can give valid information on anal atresia for planning the operative treatment.

The hypophyses of 13 patients with Nelson syndrome following bilateral adrenalectomy were examined by MRI and CT. Diffuse enlargement of the hypophysis was demonstrated in 8 patients by CT and in 9 by MRI. Compared with CT, MRI provides better demonstration of tumour development, such as abnormal convexity of the cranial margin of the hypophysis (MRI 4/13, CT 1/13), displacement of the infundibulum (MRI 4/13, CT 0/13) or optic chiasm (MRI 2/13, CT 0/13). MRI also provides diagnostically important differentiation between scar tissue and recurrence of tumour following hypophysectomy (MRI 1/3, CT 0/3) and more accurate demonstration of infiltration of the cavernous sinus (MRI 4/13, CT 2/13). CT is superior only in showing the floor of the sella. MRI is the method of choice for imaging in cases of Nelson syndrome.

Fourteen patients with carcinomas of the gallbladder and eight patients with biliary duct carcinomas were examined by CT, sonography, percutaneous transhepatic cholangiography (PTC), endoscopic retrograde cholangiography (ERC) and angiography. The results were compared retrospectively. Sonography proved suitable as a screening method. For accurate demonstration, this should be supplemented by CT. PTC and ERC demonstrate intraductal extension of biliary carcinomas and of gallbladder carcinomas infiltrating the bile ducts. The value of angiography consists merely in the preoperative demonstration of the vascular anatomy.

Arterial DSA by the trans-brachial route, using a 4-French-catheter has been performed in 33 patients. In these patients, trans-femoral DSA is contra-indicated because of previous surgery or markedly reduced femoral pulsation. Intravenous DSA was not expected to provide diagnostically adequate information in these patients, in view of the well known method limitations of this method. In 20 patients, the abdominal aorta, pelvis and lower limb arteries were examined, in 14 only the leg arteries, in ten patients the arteries in the neck and in three patients the thoracic and abdominal aorta. Trans-brachial DSA provided good demonstration of the vessels in all cases.

Eighty-one patients with postoperative abdominal lymphoceles were examined by CT and ultrasound. Both methods provide accurate information regarding localisation and extent of the lymphocele. In 51 patients conservative treatment under sonographic or CT observation was carried out. In seven patients, irradiation lead to complete regression. In 21 patients, interventional radiological therapy was carried out with simultaneous irradiation in seven cases. In five patients surgery was necessary. Asymptomatic lymphoceles should be treated conservatively and only after the appearance of clinical symptoms should interventional radiological or surgical measures be carried out.

The value of various radiological signs in the follow-up of Crohn's disease has been studied in 175 radiological examinations of the gastro-intestinal tract in 39 patients. Changes in the significant radiological signs in Crohn's disease, such as spicula, cobblestone pattern, stenoses and fistulas, provide information on the development of the disease and on the effect of treatment. The signs have a prognostic significance only insofar as their persistence excludes any improvement. Radiological follow-up is particularly useful for spotting complications and for the early recognition of recurrences.

A 41-year-old patient with latent porphyria cutanea tarda is described; 8 years after mastectomy for carcinoma, sonography and CT showed multiple hepatic foci, which were at first interpreted as liver metastases. A liver biopsy was carried out during laparoscopy and u/v fluorescence and subsequent laboratory tests confirmed the diagnosis of porphyria cutanea tarda. Treatment with resochin produced almost complete resolution of the liver abnormalities within 9 months. Magnetic resonance tomography using proton-weighted SE sequences showed a few foci of high signal intensity.

MR tomography of the liver using 1.5 T has been carried out in 63 patients with focal lesions in order to demonstrate haemangiomas and to differentiate these from primary and secondary malignant liver tumours. This differentiation was possible in all patients, using conventional spin echo and inversion recovery sequences in combination with sonography. Accuracy was much less good when using gradient echo sequences. With sufficiently large tumours, measurement of relaxation time made possible diagnosis of all the 22 haemangiomas.

In nine patients with ruptured aneurysms of the abdominal aorta and in one patient with a ruptured aneurysm of a common iliac artery who also had an abdominal aortic aneurysm, CT was performed. Three of the nine patients were also examined by sonography. CT proved to be the method of choice in the diagnosis of ruptured abdominal aortic aneurysms. The most important CT signs are: demonstration of an aortic aneurysm; haematoma usually unilateral and retroperitoneal; ventral or ventro-lateral displacement of a kidney; enlargement of the psoas, which may be indistinguishable from the haematoma, possibly with direct penetration of the psoas fascia; indistinct margin of the aortic wall at the rupture site.

The signs of arterio-venous fistulae in the extremities have been evaluated by DSA in 20 patients. Angiographic signs for the presence of A-V fistulae are the following findings: dilatation of the supplying artery, elongation of the supplying artery, solitary A-V aneurysm, angiomatous A-V aneurysm, reduced blood flow distal to the A-V fistula, early venous filling, development of a venous collateral circulation and demonstration of retrograde venous flow. Angiography remains the method of choice for demonstrating A-V fistulae.