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A 21-year-old man presented with extraneural metastases to the peritoneum, pleura, bone marrow, lymph nodes, and other organs from a pulvinar high grade glioma. He had undergone a shunt operation and three tumor removals during a 6-year period. He also received radiotherapy and adjuvant chemotherapy with 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2-chloroethyl)-3-nitrosourea hydrochloride and interferon-beta. Two and a half years after the last surgery, extraneural metastasis to the peritoneal cavity was discovered. He died 13 months after the occurrence of extraneural metastases and 10 years after the initial diagnosis. Autopsy revealed tumor masses in the peritoneum, pleura, bone marrow, lymph nodes, and other organs, but no recurrent tumor of the primary lesion or metastases to other areas in the central nervous system. Systemic metastases from primary intracranial tumors are rare, but are likely to become more frequent as the prognosis of patients with brain tumors improves and the duration of survival lengthens.

Tumors in the pulvinar tend to present as circumscribed lesions with exophytic growth into the lateral and third ventricles. These lesions may be best explored via a parietal-transcortical-transventricular approach. If the tumor extends posteriorly or inferiorly, a posterior-interhemispheric-transtentorial approach may provide a good angle of access. Gross total removal of the tumors in the pulvinar of two patients was achieved by surgical sectioning of the unilateral crus of the fornix or the splenium via a transventricular or interhemispheric approach with acceptable risk. These patients are now doing well as students about 6 years following the first operations. During tumor removal, a posterior-interhemispheric-transtentorial approach combined with above-mentioned approaches was useful for orientation of the critical structures in the posterior incisural space. Knowledge of the anatomical relationships of the pulvinar to the crus of the fornix and the choroid plexus, and to the critical structures located in the posterior incisural space is extremely important for neurosurgeons.

A 56-year-old male with two mycotic aneurysms associated with infective endocarditis was treated by endovascular surgery before mitral valve replacement. Angiography revealed a ruptured proximal aneurysm and an unruptured distal aneurysm on the right middle cerebral artery. The ruptured aneurysm was successfully treated with an interlocking detachable coil, and patency of the parent artery was preserved. The unruptured distal aneurysm disappeared as a result of antibiotic therapy. Endovascular surgery of the mycotic aneurysm is less invasive and more effective than craniotomy under general anesthesia for patients with infective endocarditis.

A 55-year-old male presented with a 20-day history of nuchal pain and hypoglossal nerve paresis on the right. T2-weighted magnetic resonance (MR) imaging showed an isointense lesion with a small hypointense part in the hypoglossal canal and caudal clivus. A 66-year-old female presented with a long-standing history of left orbital pain. T2-weighted MR imaging showed a hypointense lesion occupying the orbital apex which on recurrence became isointense. The histological diagnosis of both lesions was non-specific inflammatory granulation. The T2-weighted MR imaging appearance of this entity is variable, and can change within the clinical course of the same lesion.

A 74-year-old female presented with intraventricular and subarachnoid hemorrhage due to probable rupture of a basilar artery (BA) aneurysm or a superior cerebellar artery (SCA) aneurysm. She was treated by endovascular therapy using detachable coils through the BA. The BA aneurysm was completely occluded, but part of a coil migrated into the BA from the SCA aneurysm during the procedure. The migrated coil was retrieved using a snare type endovascular retrieving device. The snare loop required concentric closure around the coil by simultaneous pulling of the corewire and a slight forward movement of the tip of the snare catheter. The SCA aneurysm was successfully occluded 1 week later using a shorter coil.

A 9-year-old boy presented with a meningioma containing a large cyst. Magnetic resonance (MR) imaging demonstrated tumor cells in the solid part of the tumor, part of the cyst wall, and cyst septum. The presence of the tumor cells in the thin cyst wall or the cyst septum is important to recognize preoperatively, and MR imaging is very useful to differentiate intratumoral cysts from peritumoral cysts in meningiomas.

A rare case of ecchordosis physaliphora clearly demonstrated by magnetic resonance (MR) imaging is described in a 48-year-old male who presented with right hearing disturbance and reduction in sensation in the right side of his face due to a large cystic schwannoma. MR imaging revealed the large cystic schwannoma as well as an abnormal clival lesion. The clival lesion was hypointense on T1-weighted images and hyperintense on T2-weighted images, and not enhanced by gadolinium-diethylenetriamine-penta-acetic acid (Gd-DTPA) administration. The clival lesion was partially removed. The histological diagnosis was ecchordosis physaliphora. The postoperative course was uneventful. The absence of enhancement of ecchordosis physaliphora by Gd-DTPA administration may be a characteristic finding, in contrast to chordoma which is generally enhanced.

Cerebrovascular disease is a lethal complication for patients with renal failure because of the hemostatic disturbance and equivocality about management of the central nervous system. Appropriate management of the renal failure in neurosurgical patients was considered on the basis of experience. Hemodialysis (HD), which is the most common dialysis method, has a serious disadvantage: the elevation of intracranial pressure during dialysis due to the "disequilibrium syndrome." It is important to stabilize the serum osmolarity during dialysis in order to prevent the disequilibrium syndrome. From this point of view, continuous ambulatory peritoneal dialysis (CAPD) has great advantages; serum osmolarity is not rapidly changed and no anticoagulants are required during dialysis. CAPD is recommended as the first method of choice in neurosurgical management of renal failure patients. However, if a patient has to be maintained with HD because of a history of laparotomy or peritonitis, it is essential to keep the serum osmolarity as stable as possible using the extracorporeal ultrafiltration method, hypernatremic HD, bicarbonate HD, and intravenous administration of glycerol.

The hemodynamics of the anterior cerebral arteries (ACAs) were studied in 28 children with moyamoya disease. In 39% of 56 cerebral hemispheres, antegrade filling of the ACAs was not verified by preoperative angiography. On the other hand, adequate collateral pathways to the ACA territory were generally not achieved by encephalomyosynangiosis (EMS) or superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis. The authors have devised new surgical methods for the revascularization of the ACA territory, which they term "encephaloarteriosynangiosis" (EAS) and "encephalogaleosynangiosis" (EGS). In these procedures, one or several burr holes are made in the frontal skull, the dura mater is incised, and either the frontal branch of the STA or the pedicled galea aponeurotica stump is placed on the surface of the frontal cortex. In addition to EMS or STA-MCA anastomosis, these methods were applied to 23 cerebral hemispheres in 14 pediatric patients. In 14 cerebral hemispheres (61%) of 10 patients, postoperative external carotid angiograms showed some cortical branches in the ACA territory, and clinical improvement was achieved in patients with transient ischemic attacks affecting the lower extremities. The results of this study demonstrate that EAS and EGS are simple and useful techniques for revascularization of the ACA territory. In addition, EGS can be applied to the territory of the posterior cerebral artery.