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Purpose: The unenhanced signs of basilar thrombosis at computed tomography (CT) is the hyperdense visualization of the basilar artery due to intravascular thrombosis. In patients who are clinically asymptomatic, hyperdense visualization of the basilar artery can be observed, if scanned with a double helical CT. Purpose of the present study was to evaluate the diagnostic significance of these changes seen at double-helical CT., Material and Method: Ten patients patients underwent double-helical CT of a portion of the base of the skull. In each case, 5-mm and 10-mm fused slices were obtained. The patency of the visualized vessels was then documented using contrast-enhanced images., Results: The differences in attenuation between the 5-mm and 10-mm fused slices obtained at native examinations were a median 11 HU. Subsequent contrast enhanced studies documented patency of the examined vessels., Conclusion: The present data show that the hyperdense basilar artery as a sign of thrombotic occlusion is not valid when thin, fused slices are obtained at double-helical CT.

The following publication is an overview looking at the diagnostic possibilities of magnetic resonance imaging regarding diseases of the pancreas and showing image examples. We emphasize new techniques like the MRCP showing meaningful indications and diagnostic limitations.

Purpose: The purpose of this work was to determine potential causes of foot pain in patients who have had a surgical release of the plantar fascia for treatment of fasciitis., Method: We studied 17 patients (15 women, 2 men; age range 22-59 years, mean 40 years) with foot pain after undergoing a fasciotomy. Fourteen unilateral and three bilateral procedures accounted for the 20 ankles evaluated. Mean duration after surgery was 22 months (range 3-53 months). Each patient was instructed to localize the pain to a region of the foot; classify the pain as new onset, persistent, or recurrent; and characterize it as to the action that produced the greatest pain. T1-weighted sagittal and dual-echo T2-weighted images in the sagittal, coronal, and axial planes were obtained in a 1.5 T magnet. The MR studies were evaluated for abnormalities of the plantar fascia, perifascial soft tissues, tendons, and osseous structures., Results: The plantar fascia appeared thick in all ankles (mean 8.0 mm, range 6-12 mm). A total of 25 symptomatic sites were assessed. An acute plantar fascia rupture explained plantar symptoms in two feet. In another 16 feet (12 with plantar heel pain and 4 with nonspecific heel pain), 6 had documentation of acute plantar fasciitis and 9 demonstrated perifascial edema. Of the latter nine feet, five demonstrated abnormalities of the posterior tibialis, peroneus longus, and peroneus brevis tendons. The pain localized to the medial arch in six feet; five feet had abnormalities of the posterior tibialis tendon and one foot demonstrated edema in the flexor digitorum brevis muscle. The pain localized to the lateral midfoot in one foot, which had a cuboid stress fracture., Conclusion: The cause of foot pain in patients who had a plantar fasciotomy appeared to be multifactorial. Three likely causes of pain were identified: persistent or recurrent acute plantar fasciitis, pathology related to arch instability, and structural failure from overload.

Purpose: To determine energy exposure and temperature changes in routine magnetic resonance imaging practice., Materials and Methods: Body core and skin temperatures were compared in 155 persons (143 patients, 12 volunteers) undergoing routine magnetic resonance examinations with a 1.5 T field-strength magnetic resonance tomography unit using a fluoroptic temperature measurement system., Results: Average applied energy was 0.3 W/kg for whole body and 1.92 W/kg for spatially localized SAR. The maximum whole-body SAR was 1.43 W/kg spatially localized. Body core temperatures differed from those of the control group by a median 0.1 degree C and only a few patients (16.8%) exceeded the limit (+/- 0.5%) at which regulatory mechanisms set in. All patients remained within the normal physiological circadian temperature range (+/- 1 degree C). Skin temperature rose a median 0.49 degree C, with a maximal increase of 5.31 degrees C, which may be considered to be within the limits of physiological temperature change., Conclusions: Clinically relevant warming of the body is unlikely in routine magnetic resonance imaging practice.

Purpose: To evaluate dynamic MR imaging of the pituitary gland., Material and Methods: 19 patients with suspected mass lesions of the pituitary gland were examined at 1.5 Tesla with dynamic and standard MRI using a Turbo-FLASH sequence (1 image/s for 40 s)., Results: In 13/19 patients microadenomas were detected. One of the 13 microadenomas was detected using dynamic imaging and was not seen on standard MRI. The remaining 12 microadenomas were diagnosed with standard MRI., Conclusion: Dynamic imaging of the pituitary gland is a time-consuming and costly diagnostic technique. If laboratory results suggest the presence of a microadenoma and conventional MRI is unable to localise it, dynamic imaging should be performed.

For the first time, magnetic resonance cholangiopancretography (MRCP) provides images of the biliary and pancreatic ducts based on 3D data similar to those we are used to from endoscopic retrograde cholangiopancreatography (ERCP) and percutaneous transhepatic cholangiography (PTC). Extraordinarily impressing is the fact that no contrast media have to be applied. The following manuscript shows technical basics and the development of this technique from gradient echo sequences to the recent single-shot techniques. Furthermore possibilities and limitations of MRCP will be discussed with respect to certain illnesses.

Purpose: To determine whether the addition of MR mammography (MRM) is useful in excluding malignant lesions and how reliable negative MRM findings are., Methods: Amongst 694 MRM's, those originally regarded as normal were retrospectively reappraised. 239 female patients were involved. In all these patients there were clinical, sonographic and/or mammographic findings which were not entirely normal but there was no urgent indication for histological clarification. In 46 patients there were, however, histological examinations since the patients themselves insisted on it. In the remaining patients there was clinical, sonographic, mammographic and/or MRM follow-up after 12 to 18 months., Results: In 95.4% (200/239) a carcinoma could be excluded by means of MRM, in 7 patients a carcinoma in situ and in two patients an invasive carcinoma was demonstrated histologically which had not been demonstrated by MRM. Even in retrospect, no abnormality could be found., Conclusion: Because of the only moderate sensitivity of MRM in the recognition of carcinoma in situ, doubtful lesions which can be localised, should be biopsied by a stereotactic method. In cases where evaluation is difficult on clinical, sonographic and mammographic findings, MRM is of value in excluding tumours, particularly in patients with increased carcinoma risk.

Background & Aims: Arterioportal fistulas (APFs) are rare vascular disorders of the mesenteric circulation. The aim of this study was to determine the etiology, anatomical location, and main symptom at presentation of APFs, and analyze the various modes of treatment., Methods: The etiology, clinical presentation, radiographs, and treatment of 12 patients with APFs are reported in detail, and another 76 cases published since 1980 are reviewed., Results: APFs result from trauma (n = 25, 28%), iatrogenic procedures (n = 14, 16%), congenital vascular malformations (n = 13, 15%), tumor (n = 13, 15%), aneurysm (n = 12, 14%), and other causes (n = 11, 12%). The origin of APFs is the hepatic artery in the majority of patients (n = 56, 65%). The main symptoms at presentation are lower or upper gastrointestinal bleeding (n = 29, 33%), ascites (n = 23, 26%), heart failure (n = 4.5%), or diarrhea (n = 4.5%). Radiological intervention provides definitive treatment in 42% (n = 33) of patients, whereas the remainder are treated by surgery alone (n = 27, 31%) or a combination of radiological intervention and surgery (n = 8, 9%)., Conclusions: APFs result in a protean syndrome variously combining portal hypertension and other hemodynamic imbalances (heart failure, intestinal ischemia). Single or multiple interventional radiological procedures using arterial and/or venous approaches allow definitive treatment of most APFs. With increasing technological advances, it is anticipated that surgery will only be indicated in rare instances after failure of radiological intervention(s).

Purpose: MR mammography (MRM) is a sensitive diagnostic method for the detection of mammary carcinomas. The present study evaluates whether MRM can yield additional relevant data in cases of histologically confirmed mammary carcinoma., Method: Thirty-four patients with histologically confirmed mammary carcinoma were examined at MRM using a T1-weighted GE sequence and a T2-weighted SE sequence. Morphologic criteria and the dynamic contrast medium behavior of the tumors were evaluated., Results: MRM showed a 100% sensitivity and diagnostic accuracy in the detection of mammary carcinomas. Additionally, three unexpected contralateral carcinomas were discovered. In 26 patients, there was a multifocal or multicentric tumor process. In 24 patients, peritumoral edema was visualized, which corresponded histologically in 21 patients with lymphangiosis and in 3 with an inflammatory peritumoral reaction., Conclusion: Because of its high sensitivity in the diagnosis of multifocal disease and of contralateral carcinomas, MRM would seem to represent a useful addition to preoperative diagnostic procedures. The potential benefit to the patient and its cost efficiency, however, remain to be clarified.

Purpose: This is a study of 140 patients undergoing MR mammography (MRM) for evaluation of possible local recurrent disease following breast-conserving surgical treatment of mammary carcinoma. MRI was performed 1-228 months (mean 28.3 months) postoperatively., Method: MRM and interpretation of the dynamic measurements were performed in a standardized manner after positioning the patient in a double breast coil. A GRE sequence (Flash 3D, TE 5 ms, TR 12 ms, FA 25 degrees) was acquired before and 1, 2, 3, and 8 min after intravenous injection of Gd-DTPA in a dose of 0.15 mmol/kg body wt., Results: Recurrent disease was excluded in 82.8% of cases with MRM. In another 13.6% of patients, MRM was able to reliably detect recurrence of malignancy. In five cases (3.6%), MRM returned false-positive results., Conclusion: MRM is a sensitive method for detecting or excluding recurrence of malignant disease. It remains to be determined whether early detection of recurrent disease can contribute significantly to improving the prognosis in these patients.

Purpose: Evaluation of clinical usability and effectivity of newly developed, mechanically applicable minicoils attached to a wire for super-selective embolisation., Material and Methods: The new embolisation coils have been used in 16 patients aged between 28 and 90 years for the following indications: 4 haemorrhages in cases of advanced carcinoma of the cervix, one false aneurysm, 7 traumatic lesions and 4 arteriovenous fistulas. The minicoils are made of platinum and are attached to a guide wire with a connecting hook. Application is via a microcatheter in coaxial technique., Results: Percutaneous embolisation has been successful in patients. Additional surgery has not been required in any of them. Manipulation of the system is relatively easy and embolisation is made possible under controlled circumstances. In one case a minicoil disappeared into a peripheral vessel, but could be recovered percutaneously., Conclusion: The minicoils allow super-selective embolisation but, for reasons of cost, should be reserved to such vascular regions where the risk of misplacing must be kept at a minimum. Basic experience with embolisation techniques is indispensable for the application of this method.

Purpose: Arterioportal and arteriovenous fistulas (APF, AVF) are rare vascular disorders occurring as a result of congenital vascular malformation, trauma, iatrogenic causes or neoplasms. The clinical spectrum of presentation ranges from symptom-free individuals to patients with severe portal hypertension or congestive heart failure. While the majority of patients have been treated surgically in the past, interventional radiological procedures are being performed with increasing frequency. To prove this trend we reviewed the international literature., Review: We reviewed the clinical presentation and management of 79 cases reported between 1980 and 1996 in the literature and six own patients., Results: Review of the literature and our own six cases show that these fistulas can be divided in intrahepatic (n = 49, 75%) and extrahepatic fistulas (n = 20, 25%). The most important causes are trauma (n = 29, 37%), iatrogenic induced by procedures (n = 21, 27%) and congenital vascular malformations (n = 10, 13%). APFs and AVFs can be diagnosed by ultrasound, computed tomography and magnetic resonance imaging. Angiography confirms the diagnosis and in many cases allows definitive interventional radiologic treatment., Conclusion: Management of AVFs and APFs remains a challenge. However, interventional radiologic procedures provide a safe, low-cost, and effective method for treatment. Due to these facts in the last three years we notice an increasing part of interventional procedures for treatment.

Objective: Our purpose was to describe the morphologic appearance of musculoskeletal lesions in patients with cystic echinococcosis shown by CT and MR imaging., Conclusion: Patients with musculoskeletal lesions of cystic echinococcosis typically have cystic structures in adjacent soft tissues. These cysts morphologically resemble abscesses, with peripheral uptake of contrast medium and variable signal intensities on T1-weighted MR images. The absence of calcifications or endovesicular daughter cysts does not exclude the diagnosis of cystic echinococcosis.

Purpose: To evaluate the clinical efficacy of the Amplatz device for the treatment of acute occlusions of the lower limb arteries., Materials and Methods: Forty patients with acute occlusion of the lower limb arteries (3 hours to 8 days; mean, 2 days) were treated using the Amplatz clot macerator. Acute thrombotic lower limb occlusion was due to an embolic event in 32 patients and to atherosclerotic disease in eight patients., Results: Complete success, with complete clearing of thrombotic material without an adjunctive procedure, was achieved in 75% (30 of 40) of the patients. Mean thrombectomy time in these patients was 75 seconds. Partial success, with incomplete clearing of the thrombus, requiring additional procedures such as local thrombolysis, angioplasty, or atherectomy, was achieved in 20% (eight of 40) of the patients. The Doppler index increased significantly (P < .001) from .45 before intervention to .96 after intervention. There were two failures (5%). No major complications occurred., Conclusion: Mechanical thrombectomy with use of the Amplatz device is a promising approach for quick recanalization of acute peripheral thromboembolic occlusions. Further studies are needed to prove the long-term patency after mechanical thrombectomy with use of this device.

Objective: Our objective was to determine the accuracy, precision, and reliability of MR imaging as a technique for measurement of the femoral antetorsional angle., Subjects and Methods: We used MR imaging to measure anteversion of the femoral neck in 44 patients: 19 children (range, 3-17 years old; mean, 11 years old) and 25 adults (range, 18-83 years old; mean, 29 years old)., Results: We found a high correlation between MR imaging and CT measurements (r = 77). On CT, the mean angle for children was 34 degrees and for adults it was 22.2 degrees. On MR imaging, the mean angle for children was 23.22 degrees and for adults it was 15.71 degrees. The mean anteversion angles obtained by CT exceeded those obtained by MR imaging. Mean interobserver and intraobserver agreements were high for MR imaging (r = .97 and r = .97, respectively) and for CT (r = .99 and r = .96, respectively)., Conclusion: Compared with CT as the gold standard, MR imaging measurement of femoral anteversion allows precise anatomic measurements and produces reliable, reproducible results. MR imaging is recommended for preoperative planning in pediatric patients with femoral rotation osteotomies.

Purpose: Our goal was to evaluate the potential of dynamic MRI in differentiating mastitis and inflammatory breast carcinoma. Furthermore, we evaluated the potential of breast MRI to follow up mastitis patients under antibiotic treatment., Method: Twenty-one cases of dynamic breast MR (11 mastitis, 10 inflammatory carcinomas) were reviewed. All patients had a history consistent with either mastitis or inflammatory breast carcinoma. The final diagnosis was histologically confirmed., Results: Ninety percent of the inflammatory carcinomas were found to enhance > 100% in the first minute compared with 55% for mastitis. There is no significant difference between mastitis and inflammatory carcinoma., Conclusion: While breast MR cannot currently be used definitively to distinguish inflammatory carcinoma from mastitis, the differences in dynamic enhancement may prove to be useful in follow-up of presumed mastitis in problematic cases. If after biopsy the diagnosis remains unclear, breast MR may help to (a) demonstrate the success of the antibiotic treatment and (b) diagnose coexisting or confounding inflammatory carcinoma.

The papillary cystic and solid tumor of the pancrease (PCSTP) is a primary pancreatic neoplasm of unknown etiology occurring most commonly in young women and regularly containing hemorrhagic areas. Clinical symptoms are non-specific. Although these tumors reach an average diameter of 10 cm, they are often discovered by accident. Because patients with surgically resected PCSTP have very good prognoses, it is important to distinguish these tumors from other growths in the pancreas, for example mucinous cystadenoma. Whereas, due to the variable proportion of fluid components, these tumors offer non-characteristic structure at ultrasonography, computed tomography (CT) possesses high specificity for PCSTP, particularly when calcifications are present. Angiography distinguishes these tumors from hypervascular neoplasms, such as the endocrinologically inactive islet cell tumor. Magnetic resonance tomography (MRT) is especially suited for imaging the hemorrhagic areas in solid tumor formations, as well as hemorrhagic debris in the fluid portions and layer phenomena are frequently observed.

Purpose: The distinction between mastitis and inflammatory breast carcinoma is an important one. Current methods of evaluation including mammography, ultrasound and clinical examination do not enable this distinction. Dynamic magnetic resonance mammography (MRM) is a study with potential in this regard., Material and Methods: 12 patients, in whom clinical examination, mammography and ultrasound could not distinguish between both diseases, were reviewed retrospectively by means of MRM using a 1.5 T Siemens Magnetom SP and a circular mamma coil. We used dynamic 3-D gradient echo sequences with a duration of one minute., Results: At present MRM cannot definitely distinguish between mastitis and inflammatory carcinoma, 80% of the inflammatory carcinomas were found to enhance more than 100% in the first minute, compared to 43% for mastitis. No other differences were seen., Conclusion: MRM proved useful in the follow-up of treated mastitis to demonstrate the success of antibiotic treatment of mastitis and to diagnose a histologically unconfirmed inflammatory carcinoma by means of a different follow-up.

Purpose: The purpose of this study was to explain the origin of image patterns demonstrated by conventional epidurography, which is a controversially discussed topic in recent literature., Material and Methods: After introduction of thoracic epidural catheters and iopamidol injection, conventional epidurography and CT-epidurography were performed on 25 preoperative patients. After injection of Gadolinium-DTPA MR-epidurography was performed in two patients treated for chronic pain with already introduced epidural catheters. Three volunteers also underwent identical imaging after introduction of thoracic epidural catheters and in addition helical-CT epidurography using twin-beam technology., Results: 40% of the patients demonstrated the railroad track phenomenon. We were able to prove that it is a sign of a rhythmically variable filling of segments of the lateral epidural space with contrast medium 76% of the patients demonstrated no ventral epidural space at the thoracic level. 56% of the patients showed a medial area of translucence combined with a band-shaped contrasting of the epidural space in the standard ap view. This was proven in all cases to be a plica mediana dorsalis by CT. In all volunteers who underwent helical-CT and MR epidurography we observed the railroad track phenomenon and the filling defect of the anterior thoracic epidural space., Conclusion: CT epidurography is well suited for obtaining new insights into the interpretation of findings obtained by conventional epidurography.

In order to investigate the correlation between different methods of AV-determination and to assess their reliability, we compared the results of clinical and sonographic examination with computed tomography and magnetic resonance imaging in 21 children (41 hips) preoperatively. The mean anteversion angles obtained by computed tomography (34.0 degrees +/- 13.7 degrees) appeared larger than the clinical (27.7 degrees +/- 8.5 degrees), sonographic (25.6 degrees +/- 8.0 degrees) and MRI-values (23.2 degrees +/- 12.8 degrees), which can be explained by the different measurement techniques. The inter-rater as well as intra-rater reliability was high in MRI (Pearson's correlation coefficient r = 0.97 and r = 0.97) and CT (r = 0.99 and r = 0.96) but slightly less in sonography (r = 0.88 and r = 0.88) and clinical investigation (r = 0.47 and r = 0.77). For routine use in screening of femoral anteversion clinical and sonographic methods are sufficiently accurate. But in determining the exact amount of torsion preoperatively and in planning of rotation osteotomies in children MRI and CT determination are superior. As magnetic resonance imaging requires no radiation dosage, shows non-ossified cartilaginous structures and proved its high reliability, it could replace other techniques in the future for that purpose.

The authors review the etiologies and treatments of plantar fasciitis or heel spur syndrome. They offer results of a retrospective study. Comparison of the return to work time after surgery for this condition, examinations of the effects of patient age at the time of surgery, gender, duration of pain prior to surgery, and type of surgical procedure, either endoscopic plantar fasciotomy or open plantar fasciotomy with heel spur resection, is provided.

Purpose: Anteversion of the femoral neck was measured by MRI in 19 children (37 hips) preoperatively before femoral rotation osteotomies., Material and Methods: The results of this new technique were compared with values for anteversion obtained by CT and ultrasound. The measurements were performed independently by two observers to determine the correlation between the three different methods and to assess their reliability., Results: It was possible to show a high correlation coefficient (Pearson) between MRI and CT (r = 0.77) as well as MRI and sonography (r = 0.81). The mean angles obtained by CT (34 degrees, range +5 to +82 degrees) and ultrasound (25.6 degrees, range +10 to +40 degrees) appeared larger than the MRI values (mean angle 23.2 degrees, range 0 to +65 degrees), which can be explained by the different measurement techniques. Mean inter- and intra-variability was low for MRI (r = 0.97 and r = 0.97) and CT (r = 0.99 and r = 0.96) but slightly higher for sonography (r = 0.88 and r = 0.88). MRI is a new reliable and precise method to evaluate femoral anteversion that does not require ionising radiation., Conclusion: MRI is recommended for preoperative planning of paediatric femoral rotation osteotomy patients.

Ultrasound of the abdomen was performed in 30 artificially respirated patients under intensive care conditions for 7 days per patient over a time period of 6 months to elucidate the therapeutic value of different ultrasonographic findings with respect to the diagnosis "reactive acute cholecystitis". Our results show, that neither the detection of concrements or sludge within the gallbladder, nor the transient dilatation of the bile duct, nor a transient wall-thickening or the occurrence of a three-layered wall of the gallbladder can be interpreted as reliable sonographic criteria for the occurrence of an acute reactive cholecystitis. From this we conclude, that reactive acute cholecystitis leading to the indication for cholecystectomy can only be diagnosed from the combination of clinical and sonographic findings. However, reactive acute cholecystitis can almost certainly be excluded, even in obscure upper abdominal symptoms, when the sonogram of the gallbladder is normal.

"Dynamic" double contrast arthro-CT in internal and external rotation was performed on 42 patients with recurrent subluxation of the shoulder. The differential distribution of contrast and air caused by the rotation resulted in optimal demonstration of the capsulo-labrale components responsible for joint stability. In 22 patients there appeared to be an indication for arthroscopy; this confirmed the previous findings. In all cases the anterior part of the capsule and the middle and lower labrum were seen best during internal rotation. In this way all the 15 anterior capsule lesions could be seen, as well as 16 out of 17 Bankart lesions; it also showed one lesion of the middle labrum which had been masked by a haemarthrosis during external rotation. The study also defined lesions of the upper labrum caused by a different pathological mechanism which was present in 7 patients (6 Andrews and 1 S.L.A.P. lesion). These and 2 posterior labrum tears could be diagnosed during external rotation. Sensitivity for lesions of the anterior labrum was 95%.

Percutaneous aspiration thrombembolectomy (PAT) is a very suitable method for the recanalization of the popliteal and lower limb arteries after embolic occlusion. In thrombotic occlusion in patients with arteriosclerotic disease, PAT can easily be combined with other interventional procedures, yielding good results. With the use of PAT the dose of regionally effective fibrinolytic drugs, which may be additionally administered, can be significantly reduced.

Revealing a sensitivity of 97.5% and a specificity of 95.12% this study emphasizes the excellent diagnostic value of sonography in the elucidation of patients with clinical signs of "acute appendicitis". Evaluation of morphology on the one hand and maximal diameter of the organ and the organ wall on the other, in conjunction with the clinical presentation, allows a restrictive management of the surgical treatment and thus decreases the rate of negative laparotomy.

93 patients with 102 intraarticular calcaneus fractures (ICF) were examined by CT from 1986 to 1992. The images were evaluated with the use of a modified classification based on the number of fractured heel bone facets (2 facets in 4.8%, 3 facets in 53.9%, 4 facets in 32.3%, comminution in 8.8% of the fractures), the involvement of the calcaneus-cuboid joint (60.8%) and the fracture mechanism (tongue-type in 28.4%, joint depression in 62.7%) with the weight-bearing calcaneal compartments taken into special consideration. In that way, each intraarticular calcaneus fracture could be scored, enabling a fast diagnosis comprising factors relevant for the therapy and prognosis.

Historically, patients suffering from fibrous dysplasia of the metatarsals faced amputation or resection as the treatments of choice. Although the lesion itself is not malignant, pain, swelling, and disability dictated the treatment. With recent refinements in microvascular surgery, vascularized bone grafting has offered a viable alternative for this and similar conditions that offers the potential for a functional, pain-free foot.