Moderate changes in body temperature can influence the outcome of cerebral ischemic insults and the effect of drugs. Body temperature was measured continuously for 24 hours in rats subjected to permanent occlusion of the middle cerebral artery (MCA) by either coagulation or thread insertion, and the results correlated with the histology of the hypothalamus. The body temperature did not change after MCA occlusion by coagulation and the hypothalamus was intact in all rats. In contrast, the body temperature rapidly increased from about 38°C to more than 39.5°C after MCA occlusion using intraluminal thread, and hyperthermia continued for at least 6 hours in all rats. Histological evaluation revealed neuronal damage in the preoptic area of the hypothalamus in all rats undergoing thread occlusion. Long duration hyperthermia must be prevented after permanent MCA occlusion when the intraluminal thread occlusion model is used in chronic experiments.
Transduction of the herpes simplex virus thymidine kinase (HSV-tk) into vascular endothelial cells using a replication-defective adenoviral vector (Ad.CMV-tk) to confer sensitivity to ganciclovir (GCV) was investigated. The cytotoxic sensitivity of bovine aortic endothelial cells (BAEC) to GCV following Ad.CMV-tk transduction at multiplicity of infection of 100 was ten-fold that of 9L glioma cells in vitro. Deoxyribonucleic acid fragmentation was detected in these BAEC. A co-culture experiment using BAEC transduced with Ad.CMV-tk (BAEC-tk) and 9L cells expressing β-galactosidase (9L-Lac Z) showed about 70% tumoricidal effect under the conditions of one BAEC-tk cell in 10 9L-Lac Z cells. Tumor-bearing Fisher 344 rats, an experimental brain tumor model, received Ad.CMV-tk intratumorally at 7 days after tumor implantation, and were subsequently treated with intraperitoneal GCV (100 mg/kg). Histological examination found the vascular endothelial cells adjacent to 9L glioma tissue revealed apoptosis. These results suggest that vascular endothelial cells are an attractive target for adenoviral-mediated HSV-tk gene therapy.
The antitumor activities of recombinant human tumor necrosis factor-α (rH-TNFα) and liposome-entrapped rH-TNFα were evaluated in various glioma cell lines and a rat brain T9 gliosarcoma model. rH-TNFα had a direct cytotoxic activity against various glioma cell lines in vitro, and indirect cytotoxic activity against gliosarcoma (T9) in vivo. Liposome-entrapped rH-TNFα had increased direct cytotoxic activity in vitro, and against experimentally induced brain tumors in vivo. The effects in vivo were probably due to vascular damage of the tumor vessels as shown by histological examination and activation of cytotoxic macrophages as shown in vitro. These results indicate that the general or local administration of liposome-entrapped rH-TNFα may become a useful adjunct treatment for malignant brain tumor.
A 63-year-old female presented with an anterior cerebral artery aneurysm associated with accessory middle cerebral artery. The aneurysm was located on one of the duplicate anterior communicating arteries, and the accessory middle cerebral artery originated from the anterior cerebral artery adjacent to this aneurysm. The recurrent artery of Heubner was not recognized. The accessory middle cerebral artery may have been involved in the genesis of the aneurysm by changing the hemodynamics in the anterior cerebral arteries.
An 8-year-old girl presented with coexistence of ganglioglioma and cortical dysplasia manifesting as intractable epilepsy. Preoperative computed tomography demonstrated a small calcified lesion in the left frontal lobe which was not diagnosed as ganglioglioma. Magnetic resonance imaging also failed to demonstrate positive evidence of ganglioglioma or cortical dysplasia. A calcified tumor and the surrounding epileptogenic areas were resected under electrocorticography (ECoG) guidance. Histological examination revealed coexistence of ganglioglioma and cortical dysplasia. The patient became seizurefree after surgery. Resection of the ganglioglioma together with the adjacent epileptogenic area under intraoperative ECoG guidance is important to achieve a successful surgical result in patients with ganglioglioma.
A 36-year-old female was admitted with leptomeningeal melanoma associated with straight sinus thrombosis manifesting as headache and vomiting. Computed tomography and magnetic resonance imaging showed the subarachnoid space was diffusely enhanced. Her consciousness rapidly deteriorated to a coma. Angiography demonstrated straight sinus thrombosis. Thrombolysis by superselective catheterization and infusion of urokinase was successfully performed. She recovered consciousness, but developed paraparesis 2 weeks later. Malignant melanoma with meningeal dissemination was diagnosed by an open biopsy of the lumbar lesion. Angiitis induced by the infiltration of tumor cells and activation of the blood coagulation cascade was probably the causative mechanism of the sinus thrombosis.
A 38-year-old male presented with a posterior fossa ependymoma with unusual extension from the cerebellopontine angle to the pineal region. Magnetic resonance imaging clearly demonstrated that these two components were continuous through the right ambient cistern. Computed tomography using a bone algorithm revealed enlargement of the right internal auditory canal. This case suggests that ependymoma can extend anywhere within the subarachnoid space along the path of least resistance.
A 62-year-old female presented with giant cell granulomatous hypophysitis manifesting as subacute unilateral ophthalmoplegia. Neuroimaging revealed a mass lesion expanding in the pituitary fossa. The mass was totally removed through the transsphenoidal approach. The histological diagnosis was giant cell granuloma. The oculomotor nerve paresis resolved completely 10 days after the operation. Giant cell granulomatous hypophysitis is symptomatically and radiologically indistinguishable from non-functioning pituitary adenoma, but is less likely to cause visual disturbance than pituitary adenoma. Giant cell granulomatous hypophysitis should be considered in the differential diagnosis of sellar and suprasellar lesions, particularly if oculomotor nerve paresis is observed without impaired visual field or acuity.
A 61-year-old female presented with a rare case of hemifacial spasm (HFS) resulting from facial nerve compression near the internal acoustic meatus. She underwent a first surgery for microvascular decompression at the root entry zone of the facial nerve, but this did not achieve resolution of the HFS. During the second surgery, the meatal loop of the anterior inferior cerebellar artery (AICA) was found to be the offending artery near the internal acoustic meatus. When the AICA was dissected and separated from the facial nerve, abnormal muscle responses of the mentalis muscle due to electrical stimulation of the zygomatic branch of the facial nerve were abolished. Following surgery the patient was completely free of the HFS.
A 61-year-old male presented with a brain abscess manifesting as high fever and generalized convulsion attacks. Magnetic resonance (MR) imaging disclosed a ring-like enhanced lesion in the parietal lobe. Thallium-201 single photon emission computed tomography (201Tl SPECT) images demonstrated a high uptake lesion with a 201Tl uptake index on the early image of 2.21, which suggested malignant disease. The washout ratio was 0.73. His symptoms and the ring-like enhanced lesion on MR images disappeared after 2 months of antibiotic treatment. The final diagnosisdespite the was brain abscess, 201Tl SPECT findings. 201Tl SPECT washout ratio may be a better indicator of brain abscess than uptake index.