Masafumi Ohtaki

Intracranial Facial Nerve Neurinoma: Surgical Strategy of Tumor Removal and Functional Reconstruction

BACKGROUND Three cases with intracranial facial neurinoma underwent tumor removal and facial nerve reconstruction with or without tympanoplasty. Surgical strategy for each case was tailored to: (1) the site of main tumor mass, (2) its extension along the facial nerve, and (3) involvement of the auditory organs. METHODS Surgeries adopted in the three cases were: transpetrosal approach with intracranial-intratemporal facial nerve anastomosis, middle fossa and transmastoid approach with intratemporal facial nerve anstomosis and tympanoplasty, and middle fossa and transmastoid approach with intracranial-intratemporal facial nerve anastomosis and tympanoplasty. The greater auricular nerve was used as the nerve graft for all three cases. RESULTS In the follow-up period of 8-13 months there was no tumor recurrence; facial function was scored 20/90 in modified Mays scoring system in each case, but two are still in the process of functional recovery. One of the two cases who underwent tympanoplasty showed complete recovery of hearing within 1 month, and the other showed worsened hearing, which was not serviceable at 3 months postoperatively. CONCLUSION Systematic surgical approach for tumor removal, facial nerve reconstruction, and auditory reconstruction should be considered in cases with intracranial facial neurinoma due to its varied clinical features.

Effects of Hyperventilation and CO2 Inhalation on Cerebral Oxygen Metabolism of Moyamoya Disease Measured by Near-Infrared Spectroscopy

Near-infrared spectroscopy (NIR) can give continuous, direct information about cerebral oxygen metabolism not only in infants but also in adults by providing signals from oxyhemoglobin (oxy-Hb), deoxyhemoglobin (deoxy-Hb), and the redox state of cytochrome aa3 (Cyt). Using NIR, we examined the cerebral oxygen metabolism of normal adults and patients with moyamoya disease.

Diagnosis of cerebral arteriovenous malformations with three-dimensional CT angiography

High speed spiral computed tomography (CT) is well known to be a good tool to visualize cerebrovascular lesions; this technique is called three-dimensional CT angiography (3D-CTA). Although 3D-CTA is widely accepted to diagnose cerebral aneurysms because it is less invasive and more useful than digital subtraction angiography, little is known about its diagnostic potential for arteriovenous malformation (AVM). In this study, the efficacy of 3D-CTA in diagnosis and surgical planning was investigated in 21 patients with AVMs. AVMs located in the cerebral hemisphere, the cerebellum, the basal ganglia, the brain stem, the corpus callosum, the optic chiasm and the lateral ventricle. 3D-CTA clearly demonstrated the three-dimensional feature of the feeding artery, the nidus, the draining vein and the surrounding normal structures. We conclude that 3D-CTA is essential to preoperative planning for the appropriate surgical approach toward the AVM.

Diagnosis of unruptured intracranial aneurysms with three-dimensional CT angiography

The usefulness of three-dimensional CT angiography (3D-CTA) for the diagnosis of unruptured cerebral aneurysms was compared with that of MR angiography (MRA) and digital subtraction angiography (DSA).

Association of a Subperiosteal Hematoma With Minor Injury.

Abstract An intraorbitalsubperiosteal hematoma is a rare clinical entity that is usually caused by head trauma. The authors experienced a patient involving an intraorbital hemorrhage that was associated with minor injury in the forehead and that required surgical decompression. The authors describe this rare case involving an intraorbitalsubperiosteal hematoma that occurred in a conscious young boy who had no remarkable head injury and who had sudden onset of proptosis. Three-dimensional computed tomography, which was conducted with a volume-rendering method, was very useful, and the transorbital approach that was used to remove the hematoma was very effective. The patient showed good recovery. The pathogenesis of the intraorbitalsubperiosteal hemorrhage could not be fully explained, and, thus, the authors suggest that a possible pathogenesis involved the migration of the hemorrhage from the forehead into the intraorbital region.