An experimental model of meningeal dissemination was developed by intracisternal inoculation of human medulloblastoma (ONS-76) cells into nude mice. All mice died within 65 days after inoculation of 1 × 107 tumor cells. The median survival time was 56 days. Clinical signs and histological findings were similar to those in medulloblastoma patients with meningeal dissemination. Immunohistochemical studies showed that ONS-76 cells in the subarachnoid space expressed major histocompatibility complex (MHC) class I antigens until 20 days after inoculation. After 30 days, expression of MHC class I antigens decreased and cells began to proliferate rapidly. Expression of MHC class I antigens on tumor cells may result in effective recognition by the host immune system.
A simple, inexpensive method of portable digital subtraction angiography (DSA) using an image processor (Sigma X), still-videorecorder and control panel combined with a surgical x-ray television unit can provide real time subtraction images on the monitor. This portable DSA unit was used in 161 cases (130 in the operating room and 31 in the intensive care unit). In the operating room it is useful: 1) to confirm patency of the parent artery and its branches after aneurysm clipping, 2) to identify feeding arteries of arteriovenous malformation and to confirm total extirpation, 3) to confirm the patency of extracranial-intracranial bypass, 4) to confirm patency of the internal carotid artery and absence of flap formation after carotid endarterectomy. In the intensive care unit, it is particularly useful for visualizing cerebral vasospasm after subarachnoid hemorrhage and recanalization of an occluded major intracranial artery. Absence of intracranial circulation can be demonstrated in patients with suspected brain death.
Primary intracranial amelanotic melanoma was verified at autopsy in a 38-year-old male. Correct diagnosis of amelanotic melanoma needs electron microscopy or immunohistochemistry, since Masson staining is negative due to the absence of melanin pigment. We adopted the following criteria for clinical use: macroscopically not dark and microscopically negative for Masson staining, but ultrastructurally various melanoma types present. Although the clinical profile of this case is consistent with melanotic melanoma, the more detailed features of primary intracranial amelanotic melanoma require future study.
A 14-year-old boy presented with cerebellar ganglioglioma manifesting as severe headache and confusion. Computed tomographic scans showed a huge, partly enhanced cystic cerebellar tumor. The tumor was totally removed. Histological examination disclosed glial cells and mature ganglion cells. The latter were identified by Nissl's staining and immunostaining for neurofilaments. Ganglion cells were present in the cerebellum and the surrounding subarachnoid space. This heterotopic growth of ganglion cells enabled a firm diagnosis of cerebellar ganglioglioma.
Systemic metastases from gallbladder carcinoma occur frequently, but involvement of the central nervous system is rare. We describe such a case in a 68-year-old female. Solitary brain metastasis from gallbladder carcinoma was completely removed 4 months after operation for the primary tumor. Planned chemotherapy was then given to prevent recurrence. She was leading a normal life 4 years later. Patients with solitary brain metastasis from gallbladder carcinoma can achieve a better outcome and longer survival after removal of the brain metastasis if there is no other metastasis.
The authors describe an unusual case of pulmonary small cell carcinoma with numerous calcified metastatic nodules of the brain in a 62-year-old female. Computed tomographic scanning and magnetic resonance imaging demonstrated these lesions with ring enhancement. Autopsy revealed about 30 calcified metastatic nodules in the brain, but no calcification in the pulmonary lesion. Histological examination of the brain lesions disclosed necrosis and calcification in the center and small cell carcinoma cells in the periphery.
A rare case of delayed traumatic intracerebellar hematoma (DTICIH) in a 54-year-old male achieved an excellent outcome without surgery. Analysis of this case and other reported cases suggests that DTICIH occurs in two types: Group I with hematoma developing in previously contused areas, and Group II with hematoma developing in areas appearing normal on the initial computed tomographic scan. Group I hematomas occurred in the cerebellar cortex, but Group II hematomas occurred in the subcortical region or vermis where direct impact is less likely to have an effect. This suggests different mechanisms of development for DTICIH.
A ruptured cerebral aneurysm in a 50-year-old female with idiopathic thrombocytopenic purpura was successfully clipped after preoperative high-dose gamma-globulin therapy to control the hemorrhagic diathesis. High-dose gamma-globulin therapy with or without steroid and/or platelet transfusion is recommended for such cases if the blood pressure can be controlled and the neurological condition permits delayed surgery.
A 35-year-old female presented with moyamoya disease coincidentally associated with a persistent primitive trigeminal artery (PPTA). Bilateral encephalo-duro-arterio-synangiosis was performed and the postoperative course was uneventful. Moyamoya disease and PPTA might have a congenital origin, but moyamoya disease may be promoted by a PPTA. The hemodynamics of PPTA during progressive occlusive change in the internal carotid artery in moyamoya disease should be re-evaluated to determine its function in the development of moyamoya vessels.
A rare case of large arteriovenous malformation (AVM) with persistent primitive hypoglossal artery in a 43-year-old male was treated by staged embolization, followed by total removal. AVM associated with carotid-basilar anastomosis is quite rare, but the incidence of AVM in patients with carotid-basilar anastomosis is high. AVM associated with persistent carotid-basilar anastomosis has no distinguishing features compared with ordinary AVM, but participation of the posterior circulation as a feeder is characteristic.