BACKGROUND With the widespread use of less invasive imaging tools, such as magnetic resonance angiography and computed tomographic angiography, unruptured cerebral aneurysms are found much more often than in the past. This retrospective study was undertaken to determine the risk factors for surgical intervention in a patient with an unruptured intracranial… (More)
A case of ectopic meningioma, which was confined in the diploic space of the orbital roof, is reported. Histologically, paranasal sinus mucosa was found in the tumor specimen without sharp demarcation. Nomenclature and histogenesis of this type of meningioma are discussed.
In a series of 32 surgical cases of carotid-ophthalmic artery aneurysm, seven of the lesions were located in the "carotid cave." This special type of aneurysm is usually small and projects medially on the anteroposterior view of the angiogram. At surgery, it is located intradurally at the dural penetration of the internal carotid artery (ICA) on the… (More)
Twenty-four different kinds of fenestrated clips are introduced for the obliteration of unusual aneurysms. The clips were used for eight aneurysms of the internal carotid artery and 10 aneurysms of the vertebral artery. All but one of the aneurysms were successfully obliterated. Recommendations are made concerning the actual use of the clips.
Direct surgery for intra-axial lesions of the brain stem is considered a hazardous procedure, and morbidity of varying degrees cannot be avoided even with partial removal or biopsy. The main causes of morbidity relate to direct damage during removal of the lesion, selection of an entry route into the brain stem, and the direction of brain stem retraction.… (More)
BACKGROUND When the surgeon's approach is from behind the patient's shoulder via the infratentorial supracerebellar approach in the prone position (Concorde position), the patient's shoulder nearest the surgeon occasionally interferes with the visual route and surgical manipulation. To avoid this difficulty the author developed a modified Concorde position.… (More)
The authors report two cases in which the ophthalmic artery (OA) originated from the interdural portion of the internal carotid artery at the carotid dural ring and coursed within the dura. This configuration was observed during surgeries performed in 82 cases of juxta-dural ring aneurysms. In surgery for such an aneurysm, if the OA is not seen… (More)
OBJECTIVE AND IMPORTANCE The natural history of syringomyelia is highly unpredictable, and some patients experience improvement or stabilization without surgery. However, the mechanisms of the formation and spontaneous resolution of syringomyelia remain controversial. This report concerns two patients with syringomyelia who demonstrated spontaneous… (More)
A three-dimensional (3-D) high-definition television (Hi-Vision) system suitable for attachment to a stereoscopic operating microscope allowing 3-D medical documentation using one Hi-Vision camera and one Hi-Vision monitor is described. The system provides 3-D high-definition microneurosurgical recorded images suitable for viewing on a screen or monitor, or… (More)