The secretion of transforming growth factor-β (TGF-fl), a growth inhibitory factor with immunosuppressive properties, was investigated in one glioblastoma cell line and seven surgically resected malignant glioma cells. Cultured cells from surgically resected tumors were examined immunohistochemically for glial fibrillary acidic protein (GFAP) and S-100 protein. The levels of TGF-/β and TGF-/β2 in culture supernatants from malignant glioma cells were determined by a specific bioassay using antiTGF-/β1 and anti-TGF-/β2 antibodies. Two glioblastoma cell lines were cultured in the presence of TGF-/β1 or TGF-/β2 to assess the effect of TGF-β on the growth of glioblastoma cells. Cultured cells from surgically resected tumors were positive for both GFAP and S-100 protein. Both active and latent forms of TGF-/β1 and TGF-/β2 were detected in the culture supernatants from malignant gliomas, except in one patient with anaplastic astrocytoma which secreted only latent forms of TGF-/β1 and TGF/β2. There was no statistical difference in the levels of TGF-, β1 and TGF-/β2 in glioblastomas and anaplastic astrocytomas. Neither TGF-/β1 nor TGF-/β2 affected the growth of glioblastoma cells. These findings suggest that most malignant glioma cells secrete both TGF-/βl and TGF-/β2, can convert TGF/β from a latent to active form, and may suppress cytokine secretion by activated lymphocytes in vivo as well as in vitro.

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Perioperative nerve growth factor (NGF) levels in cerebrospinal fluid (CSF) of patients with acoustic neurinoma (14 cases), tentorial meningioma (1 case), or subarachnoid hemorrhage (1 case) were examined. Preoperative NGF levels in CSF were below the level of detection in all patients. However, NGF was found to accumulate transiently in CSF following neurosurgery. Pre and postoperative CSF obtained from a patient with acoustic neurinoma enhanced the proliferation of astrocytes in neuronal cell cultures derived from embryonic rat cortex grown in serum-free defined medium, and increased choline acetyltransferase activity of cholinergic neurons derived from embryonic rat septal area and brainstem. The effect of postoperative CSF on septal and brainstem neurons was more potent than that of preoperative CSF. These results indicate that NGF and non-NGF-type neurotrophic activities accumulate in the CSF following neurosurgery. These neurotrophic activities are probably important in the regeneration of damaged neural networks in the central nervous system.

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The magnetic resonance imaging appearance of 40 surgically confirmed intracranial meningiomas was reviewed to correlate signal intensity on T₂-weighted images with histological subtypes of meningioma. A moderate variation of signal intensity was found within a given histological subtype. The mean signal intensity scores on T₂-weighted images of the fibrous type of meningioma were significantly lower than those of the other types, and were correlated with the collagen content. The signal intensity of meningiomas on T₂-weighted images crudely predicts the histological type. Tumors significantly hypointense compared to the cortex are composed primarily of fibrous elements.

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The computed tomography (CT) and magnetic resonance (MR) imaging characteristics of two cases of small choroid plexus papilloma within the fourth ventricle are reported. CT showed the tumors as high density areas with postcontrast enhancement. MR imaging showed the tumors as basically isointense areas with marked enhancement by gadolinium-diethylenetriaminepenta-acetic acid. Important MR imaging findings included clear evidence of tumor attachment to the normal choroid plexus, location in the lower part of the fourth ventricle, and separation from the fourth ventricular floor.

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This preliminary study investigated local hemodynamic changes in intramedullary spinal arteriovenous malformation (AVM) before and after embolization. ^99mTcO₄^- was injected into the anterior spinal artery feeding the AVM via a Tracker-10 or MAGIC microcatheter. Time-dependent radioisotope images were sequentially obtained in the anteroposterior plane every 0.2 sec before and just after embolization. Local mean transit time (MTT) was then calculated for both the nidus and draining vein and compared before and after embolization. Prior to embolization, MTTs in the nidus and in the draining vein were 1.84 ± 0.62 (mean ± SD) and 2.80 ± 0.69 sec for the five patients, respectively. MTTs in both the nidus and the draining vein were significantly prolonged after embolization to 3.32 ± 1.14 and 4.90 ± 0.93 sec, respectively (p < 0.02 and p < 0.005, respectively). In vivo measurements of local hemodynamic changes in the spinal cord during the treatment of spinal AVMs could be achieved. This method may allow investigation of the hemodynamic mechanisms which induce ischemic symptoms in patients with spinal AVM.

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A 27-year-old male presented with intracranial hemorrhage due to rupture of an idiopathic dissecting aneurysm in the A₄ segment of the left anterior cerebral artery (ACA). This is a very rare location. He was successfully treated by resection of the aneurysm without neurological deficits. Surgical intervention is recommended for patients with intracranial hemorrhage due to ruptured dissecting aneurysm of the ACA to prevent rebleeding.

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A 58-year-old female, who had suffered from Weber-Christian disease for 26 years, presented with subarachnoid hemorrhage. Cerebral angiography showed dilatation of the basilar tip. An operation was performed in the chronic stage. The wall of dilated basilar artery was tough, but that of the right superior cerebellar artery was very thin and three small aneurysms were found on the right middle cerebral artery. Blood levels of fibrin degradation products, plasmin-α₂-plasmin inhibitor complex, and thrombin-antithrombin III complex were increased. The abnormality of the coagulationfibrinolysis system and the fragility of the cerebral arteries related to Weber-Christian disease were probably the cause of the subarachnoid hemorrhage.

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A 45-year-old male presented with sudden onset of severe headache, mild disorientation, and gait disturbance due to intracystic hemorrhage from a cerebellar hemangioblastoma. He was successfully treated with ventricular drainage followed by total removal of the tumor. Reported cases of intracranial hemangioblastoma with massive hemorrhage show male predominance, tend to be solid rather than cystic, and occur in supratentorial more than infratentorial locations. Thin-walled and dilated vessels in the present and other cases were a possible cause of hemorrhage. Massive hemorrhage from hemangioblastoma is rare but needs prompt treatment because of the relatively high mortality.

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A 39-year-old female presented with a syphilitic cerebral gumma mimicking small glioblastoma multiforme manifesting as visual impairment. Magnetic resonance imaging showed a low signal intensity area on T, -weighted images and marked small ring-like enhancement less than 1 cm in diameter following the administration of gadolinium. The symptoms and radiological abnormalities improved several weeks after penicillin therapy. The small ring-like enhancement was probably caused by inflammation associated with treponemal infection. A mass with a small ring-like enhancement less than 1 cm in diameter is a useful finding indicating an inflammatory lesion rather than a glial tumor.

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A 52-year-old male presented with a brainstem abscess manifesting as high fever, diplopia, and left hemiparesis. Magnetic resonance (MR) imaging with gadolinium diethylenetriamine pentaacetic acid showed the lesion as a ring-like enhanced mass consisting of a necrotic center with surrounding edema, whereas postcontrast computed tomography revealed no such confirmatory findings. He was treated with antibiotics as the lesion had been detected in the acute cerebritis stage. Serial MR images showed that the lesion decreased remarkably in size. MR imaging can detect brain abscess in the earliest inflammatory stage.

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