PURPOSE: Three-dimensional(3D) magnetic resonance(MR) projection imaging was evaluated as a noninvasive alternative to direct cholangiography for the assessment of its reliability in patients with obsructive jaundice. METHODS AND MATERIALS: A heavily T2-weighted gradient-echo sequence(PSIF) was used for 3D MR projecion imaging of the biliary system in five healthy volunteers and 25 patients with obstructive jaundice. The 3D images of the bile ducts were formed by stacking consecutive coronal MR images obtained with a fast imaging method to a maximum-intensity projection algorithm. RESULTS: In the volunteers, MR cholangiography could demonstrate the anatomy of the biliary tract in only two subjects. The extrahepatic and intraheparic bile ducts were well visualized in 23 patients with obstructive jaundice. The leve of obstruction and the grade of dilatation were dipicted with MR cholangiography in all cases. And the cause of obstruction could be determined with MR cholangiography in 18 cases, MR cholangiography was successful in two patients in whom ERCP failed. The gallbladder or dilated pancreatic duct not demonstrated by means of direct cholangiography was demonstrated with MR cholangiography in six cases.
Bile Ducts ; Biliary Tract ; Cholangiography* ; Cholangiopancreatography, Endoscopic Retrograde ; Dilatation ; Gallbladder ; Healthy Volunteers ; Humans ; Jaundice ; Jaundice, Obstructive* ; Pancreatic Ducts ; Volunteers

Femoral head and neck fractures during the course of avascular necrosis are rare with only few reports in the English literature. Moreover, there are very few reports on an analysis of the patterns of these fractures. Four cases of femoral head fracture caused by minor trauma, which were quite different from the crescent fractures during the course of avascular necrosis were analyzed in regard to the underlying disease, causes, sites, types, directions, pattern of fractures and the injury mechanism of the fractures. The results are reported with special regard to the pattern of the stress fracture of the femoral head and neck during the course of avascular necrosis.
Fractures, Stress ; Head* ; Neck* ; Necrosis*

PURPOSE: MR findings of the spinal metastasis and the tuberculosis are well known, but sometimes it might be difficult to differentiate these lesions. Therefore we reviewed and analyzed the MR findings which would be useful for the differentiation. MATERIALS AND METHODS: T1- and T2-weighted spin echo images and gadolinium-enhanced Tl-weighted images were obtained with 1. 5T and 1. 0T superconductive MR imager. We reviewed MR findings in 16 cases of spinal metastases and 24 cases of spinal tuberculosis in terms of signal intensity, contrast enhancement pattern, disc space involvement, spinal canal compressing feature and paraspinal soft tissue mass. RESULTS: The signal intensities of both lesions were hypointense on T1WI and hyperintense on T2WI except those of the metastatic lesions from the prostatic carcinoma. Heterogeneous enhancement was noted in 63% of metastasis, whereas peripheral rim enhancement was noted in 83% of spinal tuberculosis(p (.001). Spinal canal compression by collapsed vertebra was only noted in spinal metastasis, and that by paraspinal soft tissue was noted in both spinal metastasis and tuberculosis(p (.001). Disc space invasion was noted in 19% of spinal metastasis and 88% of spinal tuberculosis. Spinal tuberculosis was common at lower thoracic spine(T10) and typically involved two or more adjacent vertebral bodies(96%). CONCLUSION: The important differential point between spinal metastasis and tuberculosis was the enhancement pattern, involvement of two or more contiguous vertebral bodies and the feature of spinal canal compressing. The secondary importance was the disc space involvement pattern.
Neoplasm Metastasis* ; Spinal Canal ; Spine ; Tuberculosis ; Tuberculosis, Spinal*

PURPOSE: The purpose of this study is to assess the usefulness of dynamic MR imaging after contrast enhancement with Gd-DTPA in the differential diagnosis of hepatic focal lesions. MATERIALS AND METHODS: The population consists of 22 cases of hepatocellular carcinoma, 44 cases of hemangioma, and five cases of metastasis. Diagnosis of hepatocellular carcinoma was made by surgery, fine needle biopsy, ultrasonography, CT and conventional angiography. Hemangioma was diagnosed on the basis of ultrasonography, CT, conventional spin-echo MRI and clinical data. Diagnosis of metastasis was done by fine needle aspiration biopsy. Dynamic and delayed images were obtained using 1.5T superconductive magnetom after Gd-DTPA(0.1mmol/kg) intravenous injection. Quantitative and qualitative evaluation was done for each lesion. RESULTS: Early contrast enhancement with rapid or gradual washout was noted in 15 lesions of hepatocellular carcinoma(68.2%) ;on the delayed images, no contrast enhancement was noted in 18 lesions(81. 8%). Peripheral contrast enhancement pattern was predominantly(86.4%) observed in hemangiomas during dynamic phase. On the delayed images, homogeneous and persistent contrast enhancement of masses were noted in all hemangiomas. Characteristic centripetal fill-in pattern was observed in 32 lesions of hemangioma (72.7%). Contrast inversion of masses during contrast enhancement study was noted in all hemangiomas, while continuous negative contrast was noted in hepatocellular carcinomas and metastases. CONCLUSION: Dynamic MR imaging after contrast enhancement with Gd-DTPA is an useful method in the differential diagnosis of hepatic focal lesions.
Angiography ; Biopsy ; Biopsy, Fine-Needle ; Carcinoma, Hepatocellular ; Diagnosis ; Diagnosis, Differential* ; Evaluation Studies as Topic ; Gadolinium DTPA ; Hemangioma* ; Injections, Intravenous ; Magnetic Resonance Imaging* ; Neoplasm Metastasis ; Ultrasonography

PURPOSE:We report the results of image-guided percutaneous biopsies with a biopsy gun and evaluate the clinical usefullness. MATERIALS AND METHODS: One hundred and five biopsies under ultrasonographic or fiuoroscopic guidance were performed. Various anatomic sites were targeted (liver;50, chest;22, kidney;12, pancreas;8, intraperitoneum;7, retroperitoneum; ). RESULTS:Obtained tissue was diagnostic in 98 of the 105 biopsies(93%). In each instance, representative core tissue specimens were obtained. Evaluation of the core tissue by pathologist revealed consistent, uniform specimens that contained significant crush artifact in no case. Five biopsies yielded inadeguate tissues which were too small for histopathologic interpretation or were composed of necrotic debris. Two biopsies yielded adequate tissues, but tissues were not of the target. The diagnoses were malignancy in 77 biopsies and benign disease in 21 biopsies. No complications other than mild, localized discomfort were encountered except a transient hemoptysis and pneumothorax which was observed in two patients. CONCLUSION:Cutting biopsy with a biopsy gun provided sufficient amount of target tissue for an accurate diagnosis of malignant and benign disease. It was a safe and useful procedure for percutaneous biopsy.
Artifacts ; Biopsy* ; Diagnosis ; Hemoptysis ; Humans ; Pneumothorax

We reviewed MR angiograms to evaluate its efficacy for visualizing the renal arteries and detecting renovascular disease. 41 renal arteries in 19 patients were examined by MR angiography. 3-D time-of-flight technique was used as routine examination method for MR angiography and 2-D time-of-flight technique was added in some particular cases to visualize venous flow. Within two weeks after MR angiography was performed, 23 renal arteries in 10 patients were additionally examined by conventional angiography or intraarterial DSA. The success rates of vessel visualization on MR angiography in normal renal arteries were 100% in main 67.7% in segmental, and 11.8% in intrarenal arteries. As a result of comparative study in normal main renal arteries with MR angiograms and conventional angiograms, overall correspondence in the number and the shape was noted and the caliber discrepancy between two examination did not exceed 3.0 mm. one arteriovenous fistula with aneurysm, one stenotic artery and two occluded arteries were well evaluated One arteriovenous fistula with aneurysm, and two occluded arteries were well evaluated by MR angiography. However three stenotic lesions were misdiagnosed as occlusions on MR angiography. and the overall accuracy was 87%. We conclude that MR angiography has the potential to be a noninvasive and useful screening method for determining the number of renal arteries and for detection of abnormalities of main renal arteries.
Aneurysm ; Angiography* ; Arteries ; Arteriovenous Fistula ; Humans ; Mass Screening ; Methods ; Renal Artery*

Granular Cell Tumors(GCT) were originally described as myoblastic myomas. Subsequent scientific investigations elucidated the origin of this tumor as Schwann cells . Usually they have a predilection for head and neck, but also can occur in many other organs. This tumor is believed to originate from Schwann cells based on subsequent scientific investigations. Although it usually appears in the head and neck, it can also appear in other organs, as well. Endobronchial granular cell tumors are rather rare and should be differentiated from other common diseases of endobronchial location endobronchial diseases such as bronchogenic carcinoma and endobronchial tuberculosis, especially in Korea . We report a A case of a patient with an extremely rare condition of endobronchial granular cell tumor concurrent with malignant mediastinal tumor in a patient (delete) is reported.
Carcinoma, Bronchogenic ; Granular Cell Tumor* ; Head ; Humans ; Korea ; Myoblasts ; Myoma ; Neck ; Schwann Cells ; Tuberculosis

PURPOSE: This study was conducted to evaluate success and perforation rates of pneumatic reduction and to find the predictors of reduction failure. METHODS AND MATERIALS: We reviewed 224 cases of pediatric intussusception diagnosed by air-enema between July, 1989 and June, 1992. The mean age was 9.8 months(range, 1 month to 3 years). Logistic regression analysis was used to find predictors of reduction failure. RESULTS: Successful reduction was achieved in 197 cases(87.9% of success rate). Bowel perforation occurred in two cases(0.9% of perforation rate). There were two statistically significant predictors of failure;(1) ileoileocolic intussusception(p<.001), (2) long duration of symptom(p<.001). Surgery was performed in 26 cases (11.6%), of which seven required bowel resection. CONCLUSION: Pneumatic reduction is a useful means in the management of pediatric intussusception with a high success rate and no mortality.
Child* ; Humans ; Insufflation* ; Intussusception* ; Logistic Models ; Mortality

PURPOSE: In evaluation of the limb fracture, MR scan has been used in limited roles as evaluating the associated soft tissue injury not the fracture itself. This study aims at understanding the possible role of MR in fracture. METHODS AND MATERIALS: thirty three sets of MR scans in twenty nine patients were retrospectively analyzed. They included twelve tibial plateau fractures, four pateliar fractures, four distal femur fractures, five epiphyseal fractures and four others. RESULTS: All MRs except two showed better image and more information about the extent of the injury (93.9%). Evaluation of cartilage (which was impossible on other modalities) was possible in 28 MR scans (84.8%). Surrounding marrow change associated with fracture was also able to be evaluated. Associated soft tissue injury or other abnormality could be evaluated-cruciate or collateral ligament injury, meniscus tear, chodromalacia or osteonecrosis. In epiphyseal injury, direct demonstrability of premature bony fusion on MR took a critical role in making a management plan. CONCLUSION: MR scan in fracture has its value in evaluating the extent and degree of the injury and it is especially advantageous in detecting cartilage injury and early complication of growth plate injury.
Bone Marrow ; Cartilage ; Collateral Ligaments ; Extremities* ; Femur ; Growth Plate ; Humans ; Osteonecrosis ; Retrospective Studies ; Soft Tissue Injuries

PURPOSE: A study was performed to compare the detectability of extrahepatic duct stones between nonenhanced and enhanced computed tomography(CT). MATERIALS AND METHODS: Consecutive 30 patients with extrahepatic duct stones were analyzed with special attention to the detectability of stones between nonenhanced and enhanced CT. The extrahepatic duct was further divided into two segments, one above(suprapancereatic) and the other in(intrapancreatic) the head of the pancreas. Conspicuity of the stone was graded as "visible", "suspicious", and "invisible". Three radiologists reviewed the CT images without prior information and determined the location of stone and grade of their conspicuity. RESULTS: The stones were located at the suprapancreatic common duct in 5 patients, intrapancreatic common duct, in 15 patients and both portion of the duct in 10 patients. There was no difference in the detection rate of stones between the two images at suprapancreatic common duct, and was 93%, However, the rate at intrapancreatic common duct was 95% and 64% on nonenhanced and enhanced CT scans, respectively. The overall detection rate was 95% on nonenhance CT and 75% on enhanced CT. CONCLUSION: We concluded that nonenhanced CT was prerequisite to evaluate the extrahepatic duct stones in addition to enhanced CT.
Head ; Humans ; Pancreas ; Tomography, X-Ray Computed