Scientific publication productivity of Korean medical colleges: an analysis of 1988-1999 MEDLINE papers

To identify where the quality research activity has been and is carried out in Korea, and to examine to what extents Korean medical colleges play leading roles in the production of international research papers, we investigated the publication productivity of Korean medical colleges and their medical departments as measured by the number of papers published in foreign journals indexed in MEDLINE. The 12-year period from 1988 to 1999 is covered. A total of 4,881 papers is published in MEDLINE foreign journals by the researchers in Korean medical colleges during the period. The production of MEDLINE papers are concentrated in a few universities. More than 60% of MEDLINE foreign journal papers is published by top five universities 25% by Seoul National University, and 15% by Yonsei University. The newly established medical colleges at the University of Ulsan and Sungkyunkwan University produced outstanding numbers of papers in less than ten years. Radiology has led the internationalization of Korean medical papers. It was the most productive specialty identified in this study. The productivity of Internal medicine is on the rise from the mid-1990s, and the field began to produce the most number of papers since then.

Three Domains in Diagnostic Radiology

No abstract available.

Focal Hepatic Lesions with Peripheral Eosinophilia: Imaging Features of Various Disease

Due to the recent advent of various imaging modalities such as ultrasonography, computed tomography andmagnetic resonance imaging, as well as knowledge of the characteristic imaging features of hepatic lesions,radiologic examination plays a major role in the differential diagnosis of focal hepatic lesions. However, various'nonspecific' or 'unusual' imaging features of focal hepatic lesions are occasionally encountered, and this makescorrect diagnosis difficult. In such a situation, the presence of peripheral eosinophilia helps narrow the differential diagnoses. The aim of this pictorial essay is to describe the imaging features of various diseaseentities which cause focal hepatic lesions and peripheral eosinophilia.

Impact of Image Post-Processing on PACS Workstation: Dynamic Range Suppression(DRS) of Chest Radiographs

PURPOSE: To investigate the impact of post-processing on a PACS workstation before and after use of thedynamic range suppression method for the normal chest radiographs. MATERIALS AND METHODS: Forty normal chestradiographs of healthy adult volunteers aged 20 to 33 (average 27; M:F = 29:11) were acquired by FCR using adigital interface and then transferred to an in-house-developed PACS workstation. The image size of computed chestradiographs was 7.5MB with 1760 x 2140 matrix. An image enhancement processing named DRS, developed by theauthors, was applied to the acquired images and generated a total of 40 chest radiographs. These were presented tothree groups of observers, each consisting of one radiologist and one technician on the PACS workstation, whichhad two monitors of 1712 x 2100 resolution. So that external light would not affect the visibility of imagesduring observation, these were displayed in a light-controlled room. The J.J.Vucich method, suitably modified, wasused to evaluate the anatomical structures and physical parameters of processed and unprocessed radiographs. Usinga percentage scale, the observers evaluated both anatomical sections (seven anatomical items : cortical margins ofribs, left diaphragms, thoracic vertebrae, trachea, pulmonary vasculature, trabeculae of ribs and clavicle,diaphragm outline) and physical sections (four items : contrast, graininess, density, detail). The results for thethree groups, both before and after DRS processing, were then compared. RESULTS: There was a statisticallysignificant difference between the three groups: in the anatomical section, 78.64 before DRS and 82.55 after ; andin the physical section, 75.48 and 79.78 (p<0.05). The average values of all items were 77.06 before DRS and 81.17after (p<0.05). CONCLUSION: Post-processing of computed chest radiographs on the PACS workstation improves boththe visibility of anatomical features and general image quality. Thus, in a PACS environment, it can be a usefultool for enhancing the diagnostic efficacy of radiography.

Impact of Image Post-Processing on PACS Workstation: Dynamic Range Suppression(DRS) of Chest Radiographs

PURPOSE: To investigate the impact of post-processing on a PACS workstation before and after use of thedynamic range suppression method for the normal chest radiographs. MATERIALS AND METHODS: Forty normal chestradiographs of healthy adult volunteers aged 20 to 33 (average 27; M:F = 29:11) were acquired by FCR using adigital interface and then transferred to an in-house-developed PACS workstation. The image size of computed chestradiographs was 7.5MB with 1760 x 2140 matrix. An image enhancement processing named DRS, developed by theauthors, was applied to the acquired images and generated a total of 40 chest radiographs. These were presented tothree groups of observers, each consisting of one radiologist and one technician on the PACS workstation, whichhad two monitors of 1712 x 2100 resolution. So that external light would not affect the visibility of imagesduring observation, these were displayed in a light-controlled room. The J.J.Vucich method, suitably modified, wasused to evaluate the anatomical structures and physical parameters of processed and unprocessed radiographs. Usinga percentage scale, the observers evaluated both anatomical sections (seven anatomical items : cortical margins ofribs, left diaphragms, thoracic vertebrae, trachea, pulmonary vasculature, trabeculae of ribs and clavicle,diaphragm outline) and physical sections (four items : contrast, graininess, density, detail). The results for thethree groups, both before and after DRS processing, were then compared. RESULTS: There was a statisticallysignificant difference between the three groups: in the anatomical section, 78.64 before DRS and 82.55 after ; andin the physical section, 75.48 and 79.78 (p<0.05). The average values of all items were 77.06 before DRS and 81.17after (p<0.05). CONCLUSION: Post-processing of computed chest radiographs on the PACS workstation improves boththe visibility of anatomical features and general image quality. Thus, in a PACS environment, it can be a usefultool for enhancing the diagnostic efficacy of radiography.

Computed Radiogra p hy in Skeletal Imaging: Visual Assessment of Compressed Image Quality

PURPOSE: To evaluate the effect of lossy image compression on skeletal images and to determine the compression ratio which does not lead to difficulties when images are interpreted for diagnostic purposes. MATERIALS AND METHODS: Thirty-two computed radiographs (CR) of osteolytic bone tumors were obtained from Picture Archiving and Communication System. They were compressed to three different levels (Q factor 30, 70, 120) using the JPEG (Joint Photographic Expert Group) technique. Ninety-six pairs of uncompressed and compressed images were randomly ordered and then serially displayed on two high-resolution monitors. During a side-by-side review, three radiologists independently compared each pair of uncompressed and compressed images, and these were rated once using a five-category ordinal scale for tumor-related findings, linear structures, and soft tissues. The reviewers were then obliged to decide which image in each pair was of better quality, and finally, they were asked to evaluate the influence of image compression on diagnostic accuracy. RESULTS: The reviewers found no significant difference in image quality between uncompressed and compressed images with a Q factor 30. Compressed images with a Q factor of 70 or 120, however, revealed clinically relevant degradation. Among 96 observations of compressed images, 15 with a Q factor of 70 and 35 with a Q factor of 120 were considered inadequate for clinical purposes. CONCLUSION: If the JPEG technique is used, compressed CR skeletal images with a Q factor of 30 are acceptable for clinical application. Compressed images with a Q factor of 70 or 120 may, however, cause diagnostic difficulty and thus cannot be used for clinical purposes.

MR Imaging of Ischemic Parenchymal Lesions in Moyamoya Disease of Children

PURPOSE:To determine by means of MR imaging the ischemic status of parenchymal lesions in moyamoya disease. MATERIALS AND METHODS: Ninety-two MR images in 50 children with moyamoya disease were retrospectively reviewed. Ischemic parenchymal lesions were categorized according to the signal intensities of cortex and subcortical white matter. We also analyzed enhancement patterns, time sequential changes in the lesions, and the Prognosis for each patient, according to lesion type. RESULTS: Among one hundred and seventeen parenchymal abnormalities, 89 gyral lesions were seen in 43 children (86 %), predominantly in the frontal area (33.1%). Cortical parenchymal lesions were categorized as either type I - intermediate to high signal intensity (SI) on both T2 weighted (T2WI) and proton density images(PDI), and associated with low SI of the subcortical white matter; type II - high SI on T2WI and PDI, without low SI of the subcortical white matter; or type III - high SI on T2WI and iso SI on PDI. Thirty-three lesions were type I, ten were type II, and 43 were type III. Time sequential changes from type I to type II, and then to type III, were observed. The prognoses of patients with a type-I lesion were better than those of patients whose lesions were type II or III. CONCLUSION: Type I lesions presented with abnormal low signal intensity in the subcortical white matter, as seen on T2W1 images. This was the characteristic and earliest finding of ischemic parenchymal lesions in moyamoya disease; sequential MR images showed that type-I lesions progressed to type II or III.

Dynamic and Interactive Web-based Radiology Teaching File Using Layer and JavaScript

PURPOSE: To improve the Web-based radiology teaching file by means of a dynamic and interactive interfaceusing Layer and JavaScript. MATERIALS AND METHODS: The radiology teaching file for medical students at the author's medical school was used. By mean of a digital camera, films were digitized and compressed to JointPhotographic Expert Group (JPEG) format. Layers which had arrows or lines pointing out lesions and anatomicalstructures were converted to transparent CompuServe Graphics Interchange Format (GIF). Basically, HyperTextMark-up Language (HTML) was used for each Web page. Using JavaScript, Layers were made to be overlapped withradiologic images at the user's request. RESULTS: Each case page consisted of radiologic images and texts foradditional information and explanation. By moving the cursor or clicking onto key words, indicators pointing outcorresponding lesions and anatomical strutures were automatically shown on radiologic images. CONCLUSION: Although not compatible with some Web-browsers, a dynamic and interactive interface using Layer and JavaScript haslittle effect on the time needed for data transfer through a network, and is therefore an effective method ofaccessing radiologic images using the World-Wide Web and using these for teaching and learning.

Pulmonary Infection in AIDS

PURPOSE: To analyze the clinical and radiological manifestations of pulmonary infection in patients with AIDS. MATERIALS AND METHODS: We reviewed the medical records and analyzed retrospectively analysed the chestradiographs (n=24) and CT scans (n=11) of 26 patients with AIDS who had been followed up at our institute from1987 to June 1998. Pulmonary infections were confirmed by sputum smear and culture (n=18), pleuralexamination(n=3), bronchoalveolar lavage (n=3), autopsy (n=4), transbronchial lung biopsy (n=1) or clinicalhistory (n=9). The study group included 23 men and three women aged 25-54 (average 35.2) years. We correlated theradiologic findings with CD4 lymphocyte counts. RESULT: Pulmonary infections included tuberculosis (n=22),Pneumocystis carinii pneumonia (n=9), cytomegalovirus (n=3), and unidentified bacterial pneumonia (n=2).Radiologically pulmonary tuberculosis was classified as primary tuberculosis (n=11 ; mean CD4 counts: 41.3cells/mm3) and post-primary tuberculosis (n=11 ; mean CD4 counts: 251.3 cells/mm3). CT findings of tuberculosisincluded lymphadenitis (n=6), bronchogenic spread (n=5), large consolidation (n=4), esophago-mediastinal fistula(n=2), and cavity (n=1). Tuberculosis in AIDS responded rapidly to anti-TB medication with complete or markedresolution of lesions within three months. Radiologic findings of Pneumocystis carinii pneumonia included diffuseground glass opacities, cysts, and reticular opacities. CONCLUSION: Tuberculosis was the most common infection inpatients with AIDS in Korea, and this is attributed to the high prevalence of tuberculosis. Radiological findingsvaried with CD4+ cell count, showing those of primary tuberculosis as a patient's CD4+ cell count decreased.Pulmonary tuberculosis in AIDS responded rapidly to anti-Tb medication.

Liver Hmangioma: Comparison of Echogenecity and Contrast-enhancement on Dynamic MRI

PURPOSE: To evaluate the differences in sonographic appearance and hemodynamics between hypoechoic andhyperechoic hemangioma. MATERIAL AND METHOD: We retrospectively reviewed the sonographic appearance and MRIfindings of 23 hypoechoic hepatic hemangiomas in 16 consecutive patients. Nine were men and seven were women, witha mean age of 50 years(range, 40-72). We analyzed the sonographic appearance such as size, shape, border,echogenecity, posterior acoustic enhancement and the presence of fatty liver, and MRI findings such as signalintensity, enhancement pattern. For comparison, we also reviewed the sonographic appearance and MRI findings of 23hyperechoic hemangiomas in 16 randomly selected patients. RESULTS: There were no differences in size, shape,incidence of posterior acoustic enhancement, MR signal intensity or enhancement pattern between hypoechoic andhyperechoic hemangiomas(p>0.05, Chi-square). However, fatty infiltration of the liver and echogenic rim of themasses were more commonly seen in hypoechoic hemangiomas(9:1, 5:0, respectively, p<0.05). CONCLUSIONS: There wereno differences in MR enhomcement pattern or incidence of posterior acoustic enhancement between hypoechoichyperechoic hemangioma. The vascularity of a mass therefore seems to contribute little to its echogenecity.

Spontaneous Pneumomediastinum on CT: Related Condition and its Clinical Significance

PURPOSE: To tabulate underlying disease and to assess the clinical significance of CT-diagnosed spontaneouspneumonediastinum. MATERIALS AND METHODS: We retrospectively reviewed CT scans and medical records of 11consecutive patients with spontaneous pneumomediastinum, and analyzed their clinical history and course, and infive cases, pulmonary function. CT scans of 126 patients with idiopathic pulmonary fibrosis (IPF) collected whilethe 11 consecutive patients were being treated were analyzed for the prevalence of pneumomediastinum. We analyzedCT findings with respect to the amount and distribution of air in the mediastinum, and the presence or absence ofair outside the mediastinum. RESULTS: In the 11 patients, underlying diseases were IPF (n=4), bronchiolitisobliterans organizing pneumonia (BOOP)(n=2), bronchiectasis (n=2), tuberculous tracheal stenosis (n=1), andpulmonary tuberculosis with bullous emphysema (n=1); there was one without associated disease. Of the 126 patientswith IPF, four (3.2%) showed spontaneous pneumomediastinum. All ten with underlying diseases had severe dyspnea.In five patients, a pulmonary function test showed marked impairment. Two of four patients with IPF and both withBOOP died within 2 months of CT scanning, whereas the remaining six showed clinical improvement. The detectionrate of pneumomediastinum on plain chest radiograph was 82% (9/11). CT showed that mediastinal air was mostfrequently found in the retrosternal space. There were four cases of pneumothorax and two of subcutaneousemphysema. CONCLUSION: Spontaneous pneumomediastinum might be associated with idiopathic pulmonary fibrosis andmight be a poor prognostic factor in patients with IPF or BOOP.

Percutaneous Transluminal Angioplasty in Takayasu Arteritis: Complications and Results of Long-term Follow-up

PURPOSE: To evaluate the complications and results of long-term follow-up of percutaneous transluminalangioplasty(PTA) for the treatment of stenosis related to Takayasu arteritis. MATERIALS AND METHODS: Between December 1985 and August 1997, 21 patients(two men, 19 women; age range, 10-48 years) with Takayasu arteritis underwent PTA. There were 37 instances of stenosis(in 20 renal arteries, 10 descending aortas, 3 subclavianarteries, 3 common carotid arteries, and 1 axillary artery). In order to detect restenosis, all patients were followed up angiographically and clinically ; the period of this ranged from 8 to 121(mean 47) months. One or two redilatations were performed for restenotic arteries, and the complications and results of long-term follow-up were determined. In order to evaluate the effectiveness of PTA in Takayasu arteritis, primary and secondary patency were calculated by the Kaplan-Meier method. RESULTS: Among 37 stenotic vessels, 29 were sucessfully dialted and six partially so. Complications were aortic dissection(n=4) in aortic PTA, aortic dissection(n=1) inrenal PTA, intimal tears(n=6) in renal PTA, and hemorrhagic infart(n=1) in common carotid PTA. Restenosis occurred in 17 vessels(49%), and 12 vessels were restenosed within one year of PTA. Among 17 restenotic vessels, 14 were redilated with PTA, but after further PTA, five were restenosed. The Kaplan-Meier method showed primary patency of 62% one year after redilatation, and 46% five years after, while for secondary patency, the corresponding figures were 94% and 76%. CONCLUSION: In PTA of Takayasu arteritis, the possibility of restenosis is high, but redilatation can increase the patency rate. Intimal tearing, such as aortic dissection, may occur in PTA of Takayasu arteritis.

Percutaneous Transluminal Angioplasty and Stent Insertion in Central Venous Steno-occlusion

PURPOSE: To evaluate the efficacy of percutaneous transluminal angioplasty (PTA) and stent insertion incentral venous steno-occlusion. MATERIALS AND METHODS: Between August 1992 and January 1998, 11 patients with symptomatic central venous steno-occlusion(six stenoses and five occlusions) underwent pereutaneous treatment. Eleven PTAs were performed and stents were introduced in two patients because of incomplete PTA. During follow-up, a total of eight revisions were performed in five patients with recurrence(six stenoses and two occlusions). Success and long term patency rates were evaluated. The length and degree of the lesion and degree of residualstenosis, as well as pressure gradient through the lesion and decrease of the gradient after PTA, were correlated with patency rates. Complications during the procedures and follow-up period were evaluated. RESULT: The overall success rate was 89.5%; those of primary and revision intervention were 90.9% and 87.5%, respectively. Primary and revision patency rates were 72.7% and 50%, respectively, at 6 months, and 40% and 25% at 12 months. In five patients who underwent revision, primary and secondary patency rates were 80% and 100% at 6 months, 40% and 80% at 12 months, and 0% and 60% at 18 months. Only reduction of the pressure gradient after PTA correlated significantly with patency rates. No significant complications observed during the procedures follow-up period. CONCLUSION: PTA and stent insertion is effective for the treatment of central venous steno-occlusion.

Intrauterine Filling Defects on Hysterosalpingography Correlation with Hysteroscopic Findings

PURPOSE: To describe various hysterosalpingographic (HSG) findings of intrauterine lesions, and to determinethe correlation of these with their hysteroscopic findings. MATERIALS AND METHODS: This study involved 100patients who during a 23-month period underwent both HSG and hysteroscopic examinations. The HSG findings werecategorized as intrauterine adhesion, endometrial polyp, myoma, or 'other', and were correlated with hysteroscopicfindings and histologic diagnoses. RESULTS: Diagnoses based on HSG findings were intrauterine adhesions (n=80),endometrial polyps (n=8), myomas (n=10) and 'other' (n=2). The hysteroscopic diagnoses of these patients wereintrauterine adhesions (n=68), endometrial polyps (n=11), myomas (n=4), and 'other' (n=17). HSG and hysteroscopicdiagnoses were consistent 72 patients (72%). CONCLUSION: Lesions presenting as filling defects on HSG sometimesshow nonspecific or overlapping findings and the normal uterus may produce defects of this kind which mimicklesions.

Radiological Findings and Interventions for Iatrogenic Vascular Injuries

PURPOSE: To evaluate the radiological findings and effectiveness of radiological interventions in patientswith iatrogenic vascular injuries. MATERIALS AND METHODS: We analyzed 50 patients with iatrogenic vascularinjuries treated with radiological intervention. The causes of injuries were surgery(n=20), cardiovascularintervention(n=15), non-cardiovascular radiological intervention(n=14), and endoscopic intervention(n=1). Theinjury had resulted in hemorrhage in 35 cases. The iliac and/or femoral, hepatic, and renal vessels were commonlyinjured. Angiography, ultrasonography with Doppler examination, CT, and CT angiography were performed to diagnosevascular injuries and guide the radiological intervention. The mean follow-up period was 23 months and in 16 caseswas more than one year. RESULTS: The major radiological findings were extravasation, pseudoaneurysm,arteriovenous shunt, or vascular obstruction. To control these lesions, radiological interventions such asembolization(n=36), local urokinase administration, stent insertion, foreign body removal, ultrasonography-guidedcompression, or stent-graft insertion were performed. The clinical problems were immediately controlled by thesingle trials of radiological interventions and did not recur in 40 cases (80%). CONCLUSION: Radiologicalexaminations and interventions are useful in cases with iatrogenic vascular injuries.

Acute Pulmonary Edema after Intravenous Administration of Nonionic Contrast Media: A Case Report

We describe high-resolution CT findings of pulmonary edema following the administration of intravenous nonionic contrast media in a patient who had no previous history of cardiovascular disease ; areas of ground glass opacity and interlobular septal thickenings which partly disappeared on scans obtained 90 minutes after the initial scans. The proposed mechanisms of pulmonary edema are briefly discussed.

Multimedia Radiology Self-Learning Course on the World Wide Web

PURPOSE: The creation and maintainance of radiology teaching materials is both laborious and very time-consuming but at a teaching hospital is important. Through use of the technology offered by today's worldwide web, this problem can be efficiently solved, and on this basis, we divised a multimedia radiology self-learning course for abdominal ultrasound and CT. MATERIALS AND METHODS: A combination of video and audio tapes has been used as teaching material; the authors digitized and converted these to Hypertext Mark-up Language(HTML) format. Films were digitized with a digital camera and compressed to Joint Photographic Expert Group (JPEG) format, while audio tapes were digitized with a sound recorder and compressed to Real Audio format. RESULTS: The self-learning course for abdominal ultrasound consists of 14 steps, and that for abdominal CT, 19 steps. Both provide images, voice anrrations, and related texts and graphics. The learner can navigate the course at his/her own speed, repeating or skipping any part, as required. CONCLUSION: 'Multimedia on the Worldwide Web' will facilitate easy management and maintenauce of a self-learning course. To make this more suitable for practical use, continual upgrading on the basis of experience is needed.

Hard Palate Masses: Differential Diagnosis with CT and MR

PURPOSE: To determine the differential points of hard palate masses, using CT and MR. MATERIALS AND METHODS: MR (N=18) and CT (N=15) findings in 30 patients with pathologically-proven hard palate masses were reviewed. Masses originating in minor salivary glands were the most common (66.7%, N=20), and the remainder were accounted for by squamous cell carcinoma (N=5), lymphoma (N=2), malignant schwannoma (N=1), neurofibroma (N=1), and cholesterol granuloma (N=1). Location and demarcation of the lesions, MR signal intensity, degree of enhancement, internal architecture, and the patterns of adjacent tissue plane invasion were analyzed. RESULTS: The location of lesions originating in minor salivary glauds was as follows: paramedial, 73.7% (14/19); midline, 85.7% (6/7); and marginal,0% (0/4). On MR imaging, signal intensity and degree of enhancement showed no significant differential point except lower T2 signal intensity (3/5) and less enhancement (4/5) in squamous cell carcinoma than in other masses. Necrosiswas seen in 10/21 malignant masses (47.6%), poor demarcation in 10/21 (47.6%), bone invasion in 19/21 (90.5%), and tissue plane invasion in 15/21 (71.4%); in benign masses, the corresponding figures were 4/9 (44.4%), 1/9 (11.1%), 2/9 (22.2%), and 3/9 (33.3%). Two of 21 malignant masses (9.5%) showed none of the above charachteristics. CONCLUSION: Centrally located lesions most probably originate in minor salivary glands. In the hard palate, benign masses can show features which are generally thought to be those of malignant tumors, whereas malignant tumors can be free of such features; in differential diagnosis, caution is therefore required.

Carbon Dioxide Digital Subtraction Angiography in Percutaneous Sclerotherapy of Venous Hemangiomas

PURPOSE: To investigate the usefulness of carbon dioxide digital subtraction angiography (CO2-DSA) in direct puncture sclerotherapy of venous hemangiomas involving extremities. MATERIALS AND METHODS: Direct puncture sclerotherapy was performed in 12 patients with venous hemangioma of extremities. After direct puncture of the hemangiomas, 30-50 cc of CO2 was manually injected and digital subtraction angiograms were obtained. If draining vein was visualized, a tourniquet was applied at the proximal site to compress the draining veins. There after, radiopaque embolic materials such as 1:3 mixture of Lipiodol and absolute ethanol or ethanolamineoleate-Lipiodol-Avitene (microfibrillar collagen hemostat) mixture were slowly injected under the fluoroscopic guidance. RESULTS: Rapid injection of large amount of a CO2 enabled the visualization of wide areas of venous hemangiomas in 11 patients. Draining veins were reliably demonstrated in 10 patients and pulmonary embolism of embolic materials was effectively prevented by proximal tourniquet application. Because of radiolucent nature of CO2 retained in hemangiomas, we could clearly identify the distribution of radiopaque embolic materials under fluoroscopy. Retained CO2 also could be used as a guide for additional multiple puncture of hemangiomas. There was no systemic symptoms or complications related to CO2-DSA. CONCLUSION: CO2-DSA is a convenient, safe and useful angiographic technique in direct puncture sclerotherapy of hemangiomas involving extremities.

MR Imaging of Intramedullary Tumors of the Spinal Cord

PURPOSE: The purpose of this study was to evaluate the characteristic MR findings of intramedullary spinal cord tumors according to histologic diagnosis. MATERIALS AND METHODS: MR images of 34 patients with surgically-proven intramedullary spinal cord tumor were retrospectively reviewed. Histologic diagnosis revealed 15 ependymomas, ten astrocytomas, three hemangioblastomas, two oligidendrogliomas, one malignant schwannoma, one glioblastoma multiforme, one neuroblastoma and one ganglioglioma. MR images were analyzed for location, size, shape, signal intensity, and degree and pattern of contrast enhancement of the tumors. RESULTS: All tumors showed cord expansion and a varying extent of involvement ranging from 1.5 to 30cm. Variable degrees of contrast enhancement were seen in all cases. Cervical, cervico-thoracic, thoracic, and thoraco-lumbar spinal ependymomas accounted for three, two, six, and four cases, respectively, while four, two, and four cases of cervical, cervico-thoracic, and thoracic spinal astrocytomas respectively, were seen. Other tumors were located most commonly in the thoracic spinal cord. A sharply-defined tumor margin was seen in 13 of 15 ependymomas, in all three hemangioblastomas, one neuroblastoma and one ganglioglioma. Tumors usually showed slightly low- or iso-signal intensity on T1-weighted images and high signal intensity on T2-weighted images. Peritumoral cysts were seen in nine ependymomas, one hemangioblastoma, and one astrocytoma, while peritumoral hemorrhage was seen only in three ependymomas. Relatively homogeneous enhancement was seen in nine of 13 ependymomas, all hemangioblastomas and one neuroblastoma. All ten astrocytomas showed a poorly defined tumor margin and heterogeneous enhancement. CONCLUSION: On the basis of characteristic MR findings, intramedullary cord tumors may be histopathologically diagnosed.