Norihiko Komai

The role of angiogenic factor bFGF in the development of dural AVFs

SummaryPurposeDural arteriovenous fistulas (dAVFs) are known to be acquired disorders. Angiogenic stimulants, such as basic fibroblast growth factor (bFGF), may be involved in the evolution of this disorder. We examined the appearance and localization of bFGF, in human dAVF sinuses, versus a control using immunohistochemical techniques, to evaluate these qualitative differences.Patients and methodsFour human dural sinuses from dAVF patients, and one control dural sinus were removed at surgery or autopsy and used for this study. Immunohistochemistry for bFGF was performed in all five specimens to identify its appearance and localization. Immunohistochemistry for alpha smooth muscle actin, factor VIII related antigen, and macrophage (CD-68) were done in all tissues to identify the bFGF positive cell types.ResultsIn the control dural sinus, there was negative staining by bFGF immunohistochemistry. However, in all four sinuses of the dAVF patients, smooth muscle cells, endothelial cells, and meningeal cells were stained positively in various degrees by bFGF immunohistochemistry.ConclusionbFGF may be significant in the development of dAVFs, judging from its strong immunoreactivity in the sinuses of dAVF patients.

Transplantation of Peripheral Cholinergic Neurons into Alzheimer Model Rat Brain

The effect of transplantation of peripheral cholinergic neurons was examined in rats with a lesion of the nucleus basalis Meynert (NBM). The rats with an NBM lesion showed abnormal increase of spontaneous activity, disturbance of memory retention, and disturbance of learning acquisition. In contrast, the rats which had received transplantation of cholinergic neurons into the cerebral cortex displayed amelioration of abnormal behavior produced by the destruction of the NBM. Morphological study (acetylcholinesterase) clearly showed survival of many transplanted cholinergic cells. The present study suggests that autotransplantation of peripheral cholinergic cells may be a possible therapy for Alzheimers disease.

Preoperative embolization of meningiomas fed by ophthalmic branch arteries

BACKGROUND The efficacy of preoperative embolization for hypervascular meningiomas mainly fed by the branches of the ophthalmic arteries was examined. CASES AND METHODS Five hypervascular meningiomas mainly fed by the branches of the ophthalmic arteries, four posterior ethmoidal arteries, one anterior falx artery, and one recurrent middle meningeal artery were embolized with Gel-foam powder, polyvinyl alcohol (PVA) particles, and/or microcoils as a preoperative treatment using a microcatheter. RESULTS Catheterization of the ophthalmic and tumor feeding artery was possible and feeding arteries and lesion embolization were effective to reduce the bleeding during surgery in all cases. In three cases, visual acuity and visual field were preserved. However, in one case, visual acuity and visual field defect appeared due to the migration of Gelfoam powder (Upjohn, Kalamazoo, MI) into the retinal artery. In another case, the retinal artery was embolized with the feeding arteries since the patient was already blind. CONCLUSION Embolization of hypervascular meningioma feeding vessels arising from the ophthalmic artery is possible and effective with preservation of vision, if embolic agents are injected gently enough not to reflux into the central retinal artery.

A Light and Electron Microscopic Immunohistochemical Study of Vasoactive Intestinal Polypeptide— And Substance P-Containing Nerve Fibers along the Cerebral Blood Vessels: Comparison with Aminergic and Cholinergic Nerve Fibers

Vasoactive intestinal polypeptide (VIP)– and substance P–containing nerve fibers were observed in the cerebral blood vessels using an immunohistochemical technique. VIP-containing nerve fibers distributed in a spiral pattern, similar to that of muscle cells. Under electron microscopic observation, VIP-immunoreactive terminals lay close to a muscle cell in the inner layer of the adventitia. In contrast, substance P–containing nerve fibers showed a meshwork pattern in the outer layer of the adventitia. Using both acetylcholinesterase (AChE) staining and VIP immunohistochemistry, AChE-positive and VIP-immunoreactive nerve fibers revealed almost the same distribution in the same specimen. The present data suggest that VIP-containing nerve fibers may play a role in the smooth muscle control of the blood vessels, whereas substance P–containing nerve fibers may not take part in muscle control.

Moyamoya disease associated with intracranial aneurysms

A case of moyamoya disease associated with multiple intracranial aneurysms is reported. The aneurysms were located at the bifurcation of the basilar artery and at the precommunicating segment of the right posterior-cerebral artery. They were found to be unruptured and clipped successfully through a right frontotemporal craniotomy. Outcome of the operation was satisfactory. We propose the operative indication for these cases on the basis of operative and radiological findings, and also discuss characteristic aspects of this disease.

Effect of atrial natriuretic peptide on ischemic brain edema: changes in brain water and electrolytes.

The effects of intraventricularly administered atrial natriuretic peptide (ANP) on the brain water, sodium, and potassium contents in ischemic brain edema were investigated. By use of a three-vessel occlusion model, ischemic brain edema was produced in the rat brain by 15 minutes of global ischemia followed by recirculation. Water content was measured by means of a drying/weighing method; sodium and potassium contents were measured by means of flame photometry. The effects of intraventricular administration of ANP were evaluated by a comparison between the groups given 2 and 5 micrograms of atriopeptin II (treated) and those given 0.9% NaCl (sham-treated). The treated groups showed significant decreases in brain water (P less than 0.02) and sodium (P less than 0.01) contents at 15 and 30 minutes after recirculation, whereas the brain potassium contents remained unaltered. Before ischemia and immediately after 15 minutes of ischemia, intraventricularly administered ANP did not significantly change the brain water, sodium, or potassium contents. There was no significant difference in the effect on the amount of brain water and sodium between the two doses (2 and 5 micrograms). These effects of ANP were thought not to be mediated by primary changes in serum osmolality and sodium and potassium concentrations, because intraventricular administration of ANP did not change them significantly. The present results reveal that, in ischemic brain edema, ANP may act directly on the central nervous system to inhibit brain water and sodium accumulation.

The recurrence of primary intracranial germinomas

SummaryTwenty three cases of primary intracranial germinomas including five cases of germinomas with syncytiotrophoblastic giant cells are studied and analyzed, with special reference to the recurrence under radiotherapy. The follow-up period for all cases was 7 months to 12 years (average: 5.8 years) with that for pure germinomas ranging from 8 months to 12 years (average: 5.7 years) and that for germinomas with syncytiotrophoblastic giant cells ranging from 7 months to 11 years (average: 6.3 years). Late recurrence was observed in three cases (3/23, 13%), developing outside of the initial irradiation field.With regard to recurrence, significant correlation to radiation fields was evident, while it was not to radiation doses. Furthermore, germinoma with syncytiotrophoblastic giant cells showed a more significant tendency to recur than pure germinoma. The radiotherapy of germinomas is discussed and the clinical features of germinoma with syncytiotrophoblastic giant cells are presented.

Chronic encapsulated intracerebral hematoma during infancy: case report.

Chronic encapsulated intracerebral hematoma is a rare condition. Only four cases have been reported. The cause of this condition is unclear. A case of chronic encapsulated intracerebral hematoma in an 1-year-old infant is reported, and the characteristic findings and their causes are discussed with a literature survey.

Innervation of the Cerebral Veins as Compared with the Cerebral Arteries: A Histochemical and Electron Microscopic Study

The distribution of nerve fibers in the cerebral veins was studied by catecholamine fluorescence simultaneously with acetylcholinesterase (AChE) histochemistry. A comparison of nerve fibers in the cerebral arteries was made, The ultrastructure of terminal boutons in the veins fixed with potassium permanganate was also studied, In the adventitia of the cerebral artery, green fluorescent aminergic fibers and brownish AChE-reactive (probably cholinergic) fibers were observed. In contrast, the cerebral venous system showed no AChE-positive fibers. Catecholamine fluorescent varicose fibers were detected in the dural sinus, the internal cerebral vein, and the superficial vein of Labbé. The highest density of aminergic fibers was found in the dural sinus and the second highest in the internal cerebral vein. Most of the terminal boutons in the adventitia of the cerebral veins were found adjacent to a muscle-like cell and showed only cored vesicles under electron microscopy. Results of our study suggest that the cerebral venous system has a neurogenic innervation, mainly from aminergic fibers, which is different from the neurogenic supply to the cerebral arterial system.

Percutaneous transluminal angioplasty for the M2 portion vasospasm following SAH : development of the new microballoon and report of cases

A new silicone microballoon was developed for the percutaneous transluminal angioplasty of smaller intracranial vessels, such as A1, A2 and M2. This balloon was 0.5 x 2.0 mm in the deflated condition and became 2.2 x 6.5 mm inflated with 0.02 mL of fluid, and its bursting pressure was 2 atm. Two illustrative cases are presented. The first case was not treated in the M2 distribution. The second case of vasospasm of the left M2 portion was successfully treated with this new balloon, with prompt improvement of the neurological condition and cerebral circulation. The usefulness of our microballoon in treating a patient with vasospasm of small intracranial arteries is discussed.