PURPOSE: The purposes of this study were to analyze the MR findings of medulloblastoma, and to evaluate the subarachnoid dissemination and the significance of contrast enhanced MR of brain and spine for tumor.. MATERIALS AND METHODS: The preoperative brain MR studies of 18 patients (9 males, 9 females;mean age, 9.4 years) with surgically proved medulloblastomas were retrospectively reviewed to characterize these neoplasms with regard to their location, size, MR signal intensity, appearance after contrast enhancement, presence of cyst and necrosis, subarachnoid dissemination, and other associated findings. In 14 patients postoperative spine MR studies were evaluated for staging and therapeutic planning. RESULTS: The most frequent location of medulloblastoma was the inferior vermis and the mean tumor size was 4.1 x 3.6 x 3.9 cm. On Tl-weighted image, medulloblastomas generally had low to intermediate signal, predominantly hypointense relative to white matter. On T2-weighted image, medulloblastomas showed modetately high signal, hyperintense relative to white matter. Inhomogeneous contrast enhancement was demonstrated in 13 patients(72.2%) after injection of gadopentetate dimeglumine(Gadolinium). Cyst and necrosis within the tumor were visualized in 15 patients(83.3%). Subarachnoid disseminations of medulloblastomas were noted in 11 patients(61.1%), of which 6 demonstrated intracranial and 2 intraspinal dissemination. Three had both intracranial and intraspinal dissemination. In nine cases with intracranial lesions, there were intraparenchymal mass formation(7), subarachnoid nodules(5), infundibular lesions(2) and diffuse gyral enhancement(I). In five cases with intraspinal lesions, there were extramedullary intradural small nodules(3), central canal nodules(2), intradural masses(I)and fine nodular and sheet-like leptomeningeal enhancement(1). Other associated findings included intratumoral hemorrhage(11.1%), per/tumoral edema(44.4%), tonsillar herniation(44.4%), hydrocephalus(88.9%) and calcification(44.4%). CONCLUSION: Medulloblastomas revealed low to intermediate signal intensity on Tl-weighted image and intermediate to moderately high signal intensity on T2-weighted image, relative to cerebellar white matter. Medulloblastomas were solid tumors with cystic necrosis, which showed inhomogeneous enhancement and subarachnoid disseminations to the intracranial and intraspinal spaces after Gd-DTPA enhancement. Gd-enhanced MR of brain and spine was an useful diagnostic modality in preoperative diagnosis and in staging of postoperative cases of medulloblastomas, which was superior to postcontrast CT or precontrast MR.
Brain* ; Diagnosis ; Gadolinium DTPA ; Humans ; Male ; Medulloblastoma ; Necrosis ; Retrospective Studies ; Spine*

No abstract available.
Nasal Cavity* ; Papilloma, Inverted* ; Paranasal Sinuses*

PURPOSE: The purpose of this study is to describe Magnetic Resonance(MR) findings of two epidural cavernous malformations of the spine. MATERIALS AND METHODS: MR imaging was performed in 2 patients(29-year-old man and 54-year-old woman). Sagittal T1 -, T2-weighted images and Gadolinium (Gd)-enhanced axial and sagittal images were acquired. Two patients had surgery and MR findings were compared with surgical and histopathological findings. RESULTS: MR imaging showed high- and low-signal intensity components of these lesions that were characteristic of an epidural cavernous malformation in one case. The other case showed a high signal intensity on T2- and strong enhancement on Gd-enhanced T1 -weighted images. We think that the former may be due to mixed subacute and chronic hemorrhage and the latter may be due to blood within the endotheliumlined sinusolds without hemorrhage. CONCLUSION: These findings were well correlated with the surgical and histo-pathological findings of cavernous malformation.
Gadolinium ; Hemorrhage ; Humans ; Magnetic Resonance Imaging* ; Middle Aged ; Spine*

Acute disseminated encephalomyelitis (ADEM) is a demyelinating disease of probable autoimmune etiology. The MR images of patients with clinically suspected ADEM were retrospectively reviewed. The clinical symptoms occurred 5 days to 1 month after viral upper respiratory infection (4) and Coxsakie viral infection(1). The symptoms had begun with fever(3), headache(3), sore throat(1), and drowsy mental state (1), which progressed with monophasic course to altered mental change(2), extremity weakness(2), seizure(1) and/or cerebellary symptom(I) MRI findings of ADEM showed patchy(4), nonhemorrhagic(5), asymmetric(5) high signal intensity lesions on T2-weighted images. The number of the lesions was mostly multiple(4). The lesions mainly involved the brain stem(3) and subcortical white matter(3). Follow-up MR images of 13 days to 20 days after high dose steroid therapy showed marked improvement in two of three, which well correlated with clinical manifestations. MR findin of multiple, patchy, nonhemorrhagic and asymmetric lesions in subcortical white matter and brain stem on T2-weighted images seem to be characteristic features of ADEM, but nonspecific. Therefore, clinical correlation is required in evaluating ADEM.
Brain ; Brain Stem ; Demyelinating Diseases ; Encephalomyelitis, Acute Disseminated ; Extremities ; Follow-Up Studies ; Humans ; Magnetic Resonance Imaging* ; Retrospective Studies ; White Matter

Temporomandibular (TM) joint pain results from many etiologic factors. The aim of this study was to evaluate the utility of Bone SPECT in patients with TM joint pain. The subjects were 34 patients with TM joint pain. All patients underwent plain radiography, planar bone scan, and Bone SPECT. The intensity of radioisotope uptake at TM joint was graded into three; no increased uptake above three background activity as grade 0, uptake similar to occipital bone as grade I, and uptake similar to maxillary sinus as grade II. Clinical findings and therapeutic methods were reviewed. Twenty-seven patients (80%) out of 34 patients with TM joint pain had increased uptake in bone SPECT. Twenty-one (78%) out of 27 patients had increased uptake in the mandibular condyle and remaining six patients (22%) had uptake in the mandibular and maxillary arch, which proved to be dental problem. Seven patients out of 34 were grade as 0, four (12%) were grade I, 23 (68%) were grade II. Four patients with grade I had clicking sound and symptoms which were subsided with medication in all cases. Among 23 patients with grade II, 7 patients had clicking sound and 14 patients underwent medication and decompression therapy. With Planar bone scan, 11 cases (32%) had increased uptake in TM joint area. Plain radiography revealed narrowing, distension, erosion and limitation of TM joint in 16 cases (47%). Bone SPECT can be valuable for screening and managing the patients with TM joint pain. Patients with grade II needed intensive treatment such as joint aspiration. However degree of the radioisotope uptake did not well correlated with clinical symptoms.
Arthralgia ; Decompression ; Humans ; Joints ; Mandibular Condyle ; Mass Screening ; Maxillary Sinus ; Occipital Bone ; Radiography ; Temporomandibular Joint* ; Tomography, Emission-Computed, Single-Photon*

A construct DNA containing the cDNA for rat tyrosine hydroxylase(TH) and another construct DNA containing the cDNA for bovine L-dopa decarboxylase(DDC) were made and those genes were transferred by calcium phosphate transfection method into the immortalized rat fibroblasts. A both TH- & DDC-positive clone was identified by immunocytochemical staining. These cells produced L-dopa and dopamine and released them into the cell culture medium in vitro, which was confirmed by high performance liquid chromatography. These results have general implications for the application of gene therapy and specific implications for Parkinson disease.
Animals ; Calcium ; Cell Culture Techniques ; Chromatography, Liquid ; Clone Cells ; DNA ; DNA, Complementary ; Dopamine* ; Fibroblasts* ; Genetic Therapy ; Levodopa* ; Parkinson Disease ; Rats* ; Transfection ; Tyrosine ; Tyrosine 3-Monooxygenase

A construct DNA containing the cDNA for rat tyrosine hydroxylase(TH) and another construct DNA containing the cDNA for bovine L-dopa decarboxylase(DDC) were made and those genes were transferred by calcium phosphate transfection method into the immortalized rat fibroblasts. A both TH- & DDC-positive clone was identified by immunocytochemical staining. These cells produced L-dopa and dopamine and released them into the cell culture medium in vitro, which was confirmed by high performance liquid chromatography. These results have general implications for the application of gene therapy and specific implications for Parkinson disease.
Animals ; Calcium ; Cell Culture Techniques ; Chromatography, Liquid ; Clone Cells ; DNA ; DNA, Complementary ; Dopamine* ; Fibroblasts* ; Genetic Therapy ; Levodopa* ; Parkinson Disease ; Rats* ; Transfection ; Tyrosine ; Tyrosine 3-Monooxygenase

PURPOSE: Pilocytic astrocytoma is a benign tumor predominantly arising from cerebellum in pediatric age. But it occasionally arises in supratentorium. We describe radiologic findings of supratentorial pilocytic astrocytoma. MATERIALS AND METHODS: Eleven CT and 7 MR examinations in 11 patients were retrospectively reviewed with attention to location, CT density, MR signal intensity, and degree and pattern of contrast enhancement on CT and MR. RESULTS: The tumors were located around the third ventricle (hypothalamus in three cases, optic chiasm in three cases) and in cerebral hemisphere (temporal lobe in three cases, frontal lobe in one case, thalamus in one case). On CT, the tumors were all sharply demarcated and rarely associated with edema. The tumors showed moderate to strong contrast enhancement. Necrosis appeared frequently in tumors around the third ventricle in contrast to frequent cyst formation in hemispheric masses. On MR, the tumors appeared hypo- or isointense on T1- weighted images and hyperintense on T2- weighted images. After administration of contrast agent, the tumors showed intense enhancement more than that of CT. CONCLUSION: The typical location and radiologic findings described above are helpful in the diagnosis of the supratentorial pilocytic astrocytoma.
Astrocytoma* ; Cerebellum ; Cerebrum ; Diagnosis ; Edema ; Frontal Lobe ; Humans ; Necrosis ; Optic Chiasm ; Retrospective Studies ; Thalamus ; Third Ventricle

Intraspinal neurenteric cysts are rare congenital lesions that results from abnormal separation of germ layers in the third week of embryonic development, which may cause spinal compression. Although, the diagnosis of neurenteric cyst was very difficult prior to operation, MRI has proven to be a useful imaging modality in detection, localization and characterization of intraspinal neurenteric cysts. We recently experienced intraspinal neurenteric cyst in two patients who presented with progerssive quadriparesis. Myelography, CT myelography and MRI were taken and complete excision was performed. The MRI findings are presented and the literature is reviewed.
Diagnosis ; Embryonic Development ; Female ; Germ Layers ; Humans ; Magnetic Resonance Imaging* ; Myelography ; Neural Tube Defects* ; Pregnancy ; Quadriplegia

PURPOSE: To analyze the radiologic findings of facial nerve schwannoma. MATERIALS AND METHODS: The authors retrospectively reviewed CT and/or MR images and clinical history of eight patients with histologically provenfacial nerve schwannoma. After classifying this extratemporal and intratemporal types, clinical and radiologic findings were analysed. RESULTS: The most common clinical findings of facial nerve schwannoma were facial nervepalsy and hearing impairment in an intratemporal schwannoma(4/5), and a palpable parotid mass in an extratemporal schwannoma(3/3). On CT, each involved segment of intratemporal schwannomas(five cases) showed characteristic radiologic findings, while extratemporal schwannomas(three cases) showed masses of various types. On MRI, all tumors(two cases) showed hypointensity on T1WI, hyperintensity on T2WI, and strong enhancement on Gd-DTPA enhanced T1WI. CONCLUSION: Intratemporal facial nerve schwannomas can be easily diagnosed by characteristic clinical and radiologic findings. Extratemporal facial nerve schwannomas show nonspecific findings. However, if the tumor islocated between the superficial and the deep lobe of the parotid gland and extends to the posterior portion of thestyloid process, then facial nerve schwannoma is strongly suspected.
Facial Nerve* ; Gadolinium DTPA ; Hearing Loss ; Humans ; Magnetic Resonance Imaging ; Neurilemmoma* ; Parotid Gland