Magnetic resonance (MR) images of 14 consecutive patients with pathologically proven primary intracranial lymphoma were reviewed. All patients had a brain MR imaging before any treatment and were immunologically competent. MR images were acquired using 2.07 (n= 6) or 0.57 (n= 8) machine. The MR images were reviewed regarding the location, multiplicity, size, signal intensity, margin, shape, and the extent of surrounding edema of the lesion. Seven patients had multiple lesions, 2 to 4 in number. A total of 26 lesions was found; 25 were parenchymal lesions and one was dural lesion. The location of tumor was either central (r= 11) or peripheral (n= 14). The size of tumor was variable ranging from 0.6cm to 6.0cm in its maximal diameter. The tumors were isointense (n= 19) or hypointense (n= 7) relative to gray matter on T1-weighted images, isointense (n= 24) or hyperintense (n=2) on proton-density weighted images, and isointense (n= 21) or hyperintense (n= 5) on 78-weighted images. On gadolinium-enhanced T1-weighted images of 13 patients strong enhancement was seen in 22 of 23 lesions. Nineteen lesions showed smooth, well-defined margin, whereas remaining 7 lesions showed irregular, ill-defined margin. The shape of the tumor was diverse; round of ovoid (n= 15), lobulated (n= 9), or short linear (n= 2). These results suggest that one should consider the diagnosis of CNS lymphoma in cases with single or multiple masses that abut CSF space and show iso-or similar intensity to gray matter with strong enhancement on MR images.
Brain ; Diagnosis ; Edema ; Gray Matter ; Humans ; Lymphoma* ; Magnetic Resonance Imaging*

PURPOSE: To describe MR findings of cerebral venous sinus thrombosis. MATERIALS AND METHODS: We reviewed 11 MR images of six patients with cerebral venous sinus thrombosis. The MR images were retrospectively analyzed in terms of location and signal intensity of the thrombi, parenchymal lesions such as hemorrhage and edema, and changes in follow-up study obtained in 4 patients. RESULTS: The thrombus in venous sinus was visualized on MRI in all six patients. The most frequently involved sites were superior sagittal sinus(n=4) and left transvere sinus(n=4). Signal intensity of the thrombus was isointense or hyperintense on both T1 - and T2-weighted images with loss of normal signal void of the sinus on all sequences in all patients. Parenchymal lesion was present in five of six cases, manifested as local hemorrhage in three and edema in three cases(one case overlapped). Local edema seen in three patients was completely resolved on follow-up study of seven to 29 days intervals. CONCLUSION: It is concluded that iso- or high signal intensity with loss of signal void in venous sinus is virtually diagnostic of venous sinus thromosis. If there are local parenchymal lesions such as hemorrhage and/or edema of unknown causes, cerebral venous sinus thrombosis should be included in differential diagnosis.
Diagnosis, Differential ; Edema ; Follow-Up Studies ; Hemorrhage ; Humans ; Magnetic Resonance Imaging ; Retrospective Studies ; Sinus Thrombosis, Intracranial* ; Thrombosis

PURPOSE: The purpose of this study is to find helpful MR findings for predicting a naplastic oligodendrogl lomas. MATERIALS AND METHODS: Retrospective analysis of 46 MR images and 37 CT scans was performed for 46 patients with pathologically-proven cerebral oligodendrogliomas. A neuropathologist graded the tumors as one of low-grade (n=16), intermediate-grade (n=l2), or anaplastic oligodendroglioma (n=18). MR imaging features were retrospectively analysed with respect to histologic grading of the tumors. RESULTS: Contrast enhancement was observed always in anaplastic group (17 /17), in a portion of intermediate-grade group (4/10) but not in low-grade group (0/14). Peritumoral edema was observed infrequently in anaplastic group (4/18) or intermediate-grade group (1/12). Cystic changes (25/46) or calcifications on CT Scans (14/37) were not related with histologic grading. Grossly identifiable hemorrhage was rare in this series (2/46). Among the various imaging features, only tumor enhancement and peritumoral edema were statistically significant for trend test (p<0.05). CONCLUSION: When considering the diagnosis of oligodendrogliomas, the presence of contrast enhancement or peritumoral edema is a helpful features suggesting anaplastic oligodendrogliomas.
Diagnosis ; Edema ; Hemorrhage ; Humans ; Loma ; Magnetic Resonance Imaging ; Oligodendroglioma* ; Retrospective Studies ; Tomography, X-Ray Computed

Adenocarcinoma of the urinary bladder, including urachal carcinoma, is a rare tumor with incidence in the range between 0.5% and 2.2% of all epithelial bladder neoplasms. Ten cases of adenocarcinoma of the urinary bladder(eight cases of primary adenocarcinoma and two cases of urachal carcinoma)are presented. We described the computed tomography(CT)appearances of adenocarcinoma of the urinary bladder and tried to find out the characteristic CT findings of urachal carcinoma. CT scan were evaluated for the location of the tumors, presence of calcification in the tumor, and the tumor extension. Seven tumors were located at the dome of the bladder(70%0, two were at lateral walls, and one was at anterior wall. Seven were single mass and three were multicentric masses in the bladder. Fine punctate calcifications scattered within the tumors were detected in four cases(40%); three of the eight, primary adenocarcinoma, and one of the two, urachal carcinoma. Two urachal carcinomas were characterized by midline position and predominantly extravesical growth along the urachus. Gross extravesical extension with distant metastasis were presented in seven cases(70%) at the time of initial diagnosis. CT may be useful in evaluating the adenocarcinoma of the urinary bladder and differentiating urachal carcinoma from bladder cancer.
Adenocarcinoma* ; Diagnosis ; Incidence ; Neoplasm Metastasis ; Tomography, X-Ray Computed ; Urachus ; Urinary Bladder Neoplasms ; Urinary Bladder*

The purpose of this study is to evaluate the diagnostic accuracy of various quantitative indices for the differentiation of benign from malignant primary soft tissue tumors by FDG-PET. A series of 32 patients with a variety of histologically or clinically confirmed benign (20) or malignant (12) soft tissue lesions were evaluated with emission whole body (5min/bed position) PET after injection of [18F]FDG. Regional 20min transmission scan for the attenuation correction and calculation of SUV was performed in 16 patients (10 benign, 6malignant) followed by dynamic acquisition for 56min. Postinjection transmission scan for the attenuation correction and calculation of SUV was executed in the other 16 patients (10 benign, 6 malignant). The following indices were obtained : the peak and average SUV (pSUV, aSUV) of lesions, tumor-to-background ratio acquired at images of 51 min p.i. (TBR51), tumor-to-background ratio of areas under time-activity curves (TBRarea) and the ratio between the activities of tumor ROI at 51 min p.i. and at the time which background ROI reaches maximum activity on the time-activity curves (T51/Tmax). The pSUV, aSUV, TBR51, and TBRarea, in malignant lesions were significantly higher than those in benign lesions. We set the cut-off values of pSUV, aSUV, TBR51, TBRarea and T51/Tmax for the differentiation of benign and malignant lesions at 3.5, 2.8, 5.1, 4.3 and 1.55, respectively. The sensitivity, specificity and accuracy were 91.7%, 80.0%, 84.4% by pSUV and aSUV, 83.3%, 85.0%, 84.4% by TBR51, 83.3%, 100%, 93.8% by TBRarea and 66.7%, 70.0%, 68.8% by Tsl/Tmax. The time-activity curves did not give additional information compared to SUV or TBR. The one false negative was a case with low-grade fibrosarcoma and all four false positives were cases with inflammatory change on histology. The visual analysis of FDG-PET also detected the metastatic lesions in malignant cases with comparable accuracy. In conclusion, all pSUV, aSUV, TBR51, and TBRarea are useful metabolic semi-quantitative indices with good accuracy for the differentiation of benign from malignant soft-tissue lesions.
Fibrosarcoma ; Humans ; Positron-Emission Tomography ; Sensitivity and Specificity

Congenital leukemia is a rare disease developing within the first 4 to 6 weeks of life, whose natural history is quite different from that of childhood and adult leukemia. Leukemia cutis occurs in 25% to 30% of infants with congenital leukemia and is more frequently associated with acute myeloid leukemia than acute lymphocytic leukemia. We report a case of congenital leukemia cutis in which a walnut-sized, slightly erythematous, dome-shaped tumor that had developed at left frontal area since birth was confirmed by skin biopsy. A review and analysis of Korean literature pertaining specially to leukemia cutis in congenital leukemia is presented along with the report of an additional case.
Adult ; Biopsy ; Humans ; Infant ; Leukemia* ; Leukemia, Myeloid, Acute ; Natural History ; Parturition ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; Rare Diseases ; Skin

PURPOSE: The purpose of this study is to correlate the MR findings with clinical stage and clinical outcome, and to describe the evolutional changes of abnormal MR findings of transverse myelitis. MATERIALS AND METHODS: Medical records and spinal MR images of 23 patients with both clinical and radiological diagnosis of transverse myelitis were retrospectively reviewed. MR findings were correlated with clinical stages including interval between MR imaging and full development of clinical symptoms, and compared with the clinical outcome. RESULTS: Diffuse high signal intensity of the spinal cord on T2-weighted image with mild cord bulging (67%) and focal contrast enhancement of the cord (75%) were observed within the first four weeks after full development of clinical symptoms. The findings decreased in extent or vanished later than four weeks on either initial or follow-up MR images. Most patients with either cord atrophy or focal hemorrhagewithin the cord lesion had poor clinical outcome. CONCLUSION: The MR findings of transverse myelitis are nonspecific, which may be seen in a variety of diseases. Serial MRIs, especially follow up examination over at least one month after full development of clinical symptoms are useful in the diagnosis of transverse myelitis and predicting its prognosis.
Atrophy ; Diagnosis ; Follow-Up Studies ; Humans ; Magnetic Resonance Imaging ; Medical Records ; Myelitis, Transverse* ; Prognosis ; Retrospective Studies ; Spinal Cord

PURPOSE: The purpose of this study was to analyze the flow signal chracteristics of 3 dimensional time of flight MR angiography (3D TOF MRA) by using a flow phantom model. MATERIALS AND METHODS: Nonpulsatile flow phantom and tap water were used in this experiment. We performed FISP 3D TOF MRA with various values of parameters (repetition time ; 34-100 msec, flip angle ; 10degrees-50degrees, flow velocity ; 14.7-73.6 cm/sec, Gd-DTPA concentration ; 0.6-3.6 mmol/liter). The values of flow signal intensity (SI), signal to noise ratio (SNR) and contrast to noise ratio (CNR) were measured from base images of each MRA. The measured values were displayed graphically and analyzed statistically in relation to various parameters. RESULTS: A prolongation of repetition time resulted in a decrease of CNR of flow. As flip angles increased, SNR and CNR of flow also increased but larger flip angles of more than 40degrees rapidly saturated exit flow. As the flow velocities increased in a range of 14.7-73.6 cm/sec, SNR and CNR of flow decreased. This may be related to the phase dispersion effect of laminar flow, more dominat than the TOF effect. The addition of Gd-DTPA to water increased SNR and CNR of exit flow. There were however, no significant differences of SI, SNR or CNR of flow among the various concentrations of Gd-DTPA. CONCLUSION: An experimental MRA study using a flow phantom model was useful in understanding the flow signal characteristics of 3D TOF MRA within various MRA parameters. Our preliminary results can be used as basic data for refined flow experiments.
Angiography* ; Gadolinium DTPA ; Noise ; Signal-To-Noise Ratio ; Water

PURPOSE: The purpose of this study was to evaluate the short- and long-term effectivensess of intracavitary urokinase with percutaneous catheter drainage in Ioculated thoracic empyemas. MATERIALS AND METHODS: 15 patients were identified as second stage of Ioculated thoracic empyema by estimating nature of pleural fluid, chest PA, lateral decubitus view and CT scan. Under the guidance of fluoroscopy or ultrasound, catheter was inserted percutaneously. Instillation of urokinase was started when amount of drained fluid became less than 30ml per day with 100,000U of urokinase mixed with 100ml of normal saline. Trial of urokinase was repeated until complete drainage of empyema was demonstrated on plain chest film obtained after 48 hours. RESULTS: Successful complete drainage was achieved in 14 of 15 patients. In long-term study, complete resorption was demonstrated in 11 of 12 patients. Average dosage of used urokinase was 330,000U and mean duration of catherter insertion was 35 days. CONCLUSION: lntracavitary urokinase with percutaneous catheter drainage is a safe and effective method to facilitate drainage of Ioculated empyema and to prevent recurrence.
Catheters ; Drainage ; Empyema ; Empyema, Pleural* ; Fluoroscopy ; Humans ; Recurrence ; Thorax ; Tomography, X-Ray Computed ; Ultrasonography ; Urokinase-Type Plasminogen Activator*

PURPOSE: The purpose of this study was to evaluate the short- and long-term effectivensess of intracavitary urokinase with percutaneous catheter drainage in Ioculated thoracic empyemas. MATERIALS AND METHODS: 15 patients were identified as second stage of Ioculated thoracic empyema by estimating nature of pleural fluid, chest PA, lateral decubitus view and CT scan. Under the guidance of fluoroscopy or ultrasound, catheter was inserted percutaneously. Instillation of urokinase was started when amount of drained fluid became less than 30ml per day with 100,000U of urokinase mixed with 100ml of normal saline. Trial of urokinase was repeated until complete drainage of empyema was demonstrated on plain chest film obtained after 48 hours. RESULTS: Successful complete drainage was achieved in 14 of 15 patients. In long-term study, complete resorption was demonstrated in 11 of 12 patients. Average dosage of used urokinase was 330,000U and mean duration of catherter insertion was 35 days. CONCLUSION: lntracavitary urokinase with percutaneous catheter drainage is a safe and effective method to facilitate drainage of Ioculated empyema and to prevent recurrence.
Catheters ; Drainage ; Empyema ; Empyema, Pleural* ; Fluoroscopy ; Humans ; Recurrence ; Thorax ; Tomography, X-Ray Computed ; Ultrasonography ; Urokinase-Type Plasminogen Activator*