Regression of cerebellar tonsillar descent and hydrocephalus after endoscopic third ventriculostomy in a patient with a quadrigeminal arachnoid cyst.

Background: Posterior fossa arachnoid cysts, including quadrigeminal cistern arachnoid cysts, can occasionally cause compression of the quadrigeminal plate, leading to Sylvian aqueduct stenosis and induction of cerebellar tonsillar descent into the foramen magnum. This, in turn, can result in obstructive hydrocephalus. In such cases, the characteristic of hydrocephalus is generally considered to be hypertensive.

Ectopic ossification in the cranial dura mater in dialysis patients with secondary hyperparathyroidism.

We report the case of a 69-year-old woman with secondary hyperparathyroidism who underwent maintenance haemodialysis therapy for 17 years and who presented with severe dural calcification and right subdural haematoma. Her dura mater displayed a rock barnacle-like appearance, and cerebral superficial arteries adhered to the sclerotic lesions. On the microscopic observation, calcified tissue with a clear lamellar structure and osteopontin immunoreactivity was observed.

Diffusion-perfusion mismatch in symptomatic vasospasm after subarachnoid hemorrhage.

Diffusion-weighted and perfusion-weighted magnetic resonance (MR) imaging were investigated as a method to detect diffusion-perfusion mismatch in the early stages of vasospasm in 17 patients with acute subarachnoid hemorrhage after aneurysm clipping. Single photon emission computed tomography (SPECT) with N-isopropyl-p-[(123)I]iodoamphetamine was also performed. Diffusion-perfusion mismatch was clearly identified in the 3 patients who manifested clinical deterioration.

[Detailed magnetic resonance imaging of abducens nerve by 3D-CISS].

Although abducens nerve palsy is a relatively common disease, the abducens nerve has been almost impossible to identify, because it is one of the finest cranial nerves and runs three-dimensionally in the prepontine cistern. Three-dimensional constructive interference in steady state (3D-CISS) is helpful in visualizing fine structural elements in the central nervous system because of its higher spatial resolution and fewer artifacts from cerebrospinal fluid. In this study, we successfully visualized the abducens nerve using 3D-CISS.

Diffusion-weighted echo planar imaging of acute brain infarction: a preliminary report.

The clinical usefulness of diffusion-weighted echo planar imaging (DW-EPI) was studied in 55 patients with acute brain ischemia. Ischemic lesions were identified on DW-EPI as hyperintense regions in all patients before changes were detected by conventional magnetic resonance imaging techniques in 12 cases studied earlier than 6 hours after onset. The earliest case was verified on DW-EPI at 50 minutes after onset.

Ruptured distal anterior choroidal artery aneurysm presenting with casting intraventricular haemorrhage.

This report describes a rare case of a distal anterior choroidal artery aneurysm which developed intraventricular haemorrhage without subarachnoid haemorrhage as shown on computerized tomographic (CT) scan. A 69-year-old hypertensive man suddenly became unconscious. An emergency CT scan showed a severe intraventricular haemorrhage and a small round low-dense lesion within the haematoma at the right trigone.

The simple indicator for revascularization of acute middle cerebral artery occlusion using angiogram and ultra-early embolectomy.

Background: The purpose of the study was: (1) to find a clinical indicator for revascularization of acute middle cerebral artery (MCA) occlusion using angiograms of 100 patients examined immediately after onset and treated medically and (2) to investigate 10 ultra-early MCA embolectomies.

Methods: Quantity of collateral circulation, based on time required for conduction of contrast media to the insular portion of the MCA from the anterior cerebral artery, MCA conduction time (MCT) was graded as: Grade 1: In the arterial phase, there was conduction not only to the insular portion of the MCA but also to proximal M2; Grade 2: Conduction to the insular portion was present in late arterial phase; Grade 3: Conduction was present in capillary phase; Grade 4: Conduction was present in venous phase; Grade 5: No conduction was seen. The results of embolectomy are discussed.

Vertebral artery dissecting aneurysm rebleeding after proximal occlusion--case report.

A 38-year-old male presented with vertebral artery dissecting aneurysm manifesting as subarachnoid hemorrhage. An attempt at trapping the aneurysm failed, so the vertebral artery could only be clipped proximally. Rebleeding occurred, resulting in death, probably due to excessive length of the dissection requiring thrombosis and/or retrograde dissection due to back pressure from the contralateral vertebral artery.

Surgical intervention for angiographically unexplained subarachnoid hemorrhage--report of three cases.

We report three patients with subarachnoid hemorrhage in which no causative lesion was detected angiographically. Surgical intervention revealed a ruptured aneurysm in all three cases, which were clipped successfully. Although the prognosis for a patient with subarachnoid hemorrhage of unknown cause is good, there still remain long-lasting unpleasant complaints probably arising from psychogenic factors.

Comparison of late and early stage surgery for ruptured intracranial aneurysms.

Surgical indications and timing in serious cases (Hunt and Hess grades 4 and 5) of intracranial aneurysms were investigated. The outcomes in early surgery were compared to the clinical courses of cases intended for late surgery. The survival rate of early surgery patients was 64.

[Cerebellar hemangioblastoma developing after nephrectomy for renal cell carcinoma].

Cerebellar hemangioblastomas are known to be occasionally associated with abdominal tumors such as renal cyst and renal cell carcinoma. But most of the abdominal tumors reported are clinically silent and usually diagnosed after the hemangioblastomas have been found in the central nervous system. We report a rare case in which a renal cell carcinoma preceeded in its onset of symptoms 4 years to a cerebellar hemangioblastoma.

[Follow-up study of the giant aneurysm by CT scan after unilateal carotid ligation (author's transl)].

We report a rare case of giant aneurysm of the anterior communicating artery, which was followed up by CT scan after unilateral carotid ligation. A 50-year-old female visited our clinic complaining of headache and visual disturbance. Neurological examination revealed bitemporal hemianopsia and loss of visual acuity.