Malignant Rhabdoid Tumor

Primary CNS rhabdoid tumor is an extremely rare malignant tumor affecting children. Clinical, radiological, and histopathological features of malignant rhabdoid tumor are presented. Following the complete extirpation of a large tumor at the frontoparietal region, a 16-year-old male patient suffered from several local recurrences. The neoplasm is, defined by its histopathological and ultrastructural characteristics and by the pattern of its antigenicity as a malignant rhabdoid tumor(MRT).

Three Cases of Intracranial Hematoma Associated with Meningioma

Spontaneous intracranial hematoma in patients with brain tumors is well recognized, However, intracranial hematoma associated with meningioma has been rarely reported. Not infrequently, clinical manifestations of such tumors have been masked by the associated hematoma, which preclude correct diagnosis of these tumors. Meningioma-associated hemorrhages have been reported regardless of sex, age, or location and histology of the tumor. The mechanisms of such hemorrhage are yet to be clarified. During the last two years, we have experienced three cases of intracranial hemorrhage associated with meningioma. Two of them occurred acutely without antecedent symptoms of the meningioma and other one after gamma knife surgery of meningioma. We reviewed partinent literature and discussed possible mechanisms of these rare intratumoral or peritumoral hemorrhages associated with meningiomas.

Blood Brain Barrier and Brain Tissue Injury by Gd-DTPA in Uremia-induced Rabbits

PURPOSE: An experimental study was carried out to evaluate the morphological changes in the blood brain barrier and neighbouring brain tissue caused by Gd-DTPA in uremia-induced rabbits. MATERIALS AND METHODS: Bilateral renal arteries and veins of ten rabbits were ligated. Gd-DTPA(0.2 mmol/kg) was intravenously injectedinto seven rabbits immediately after ligation. After MRI, they were sacrificed 2 or 3 days after ligation in orderto observe light and electron microscopic changes in the blood brain barrier and brain tissue. RESULTS: MRIfindings were normal, except for enhancement of the superior and inferior sagittal sinuses on T1 weighted imagesin uremia-induced rabbits injected with Gd-DTPA. On light microscopic examination, these rabbits showed perivascular edema and glial fibrillary acidic protein expression ; electron microscopic examination showed separation of tight junctions of endothelial cells, duplication/rarefaction of basal lamina, increased lysosomes of neurons with neuronal death, demyelination of myelin, and extravasation of red blood cells. Uremia-induced rabbits injected with Gd-DTPA showed more severe changes than those without Gd-DTPA injection. CONCLUSION: Injuries to the blood brain barrier and neighbouring brain tissue were aggravated by Gd-DTPA administration inuremia-induced rabbits. These findings appear to be associated with the neurotoxicity of Gd-DTPA.