Hisato Ikeda

Considerations on surgical treatment for elderly patients with intracranial aneurysms

BACKGROUND The purpose of this study was to investigate why elderly patients have poorer outcomes and to determine indications for surgery in elderly patients. METHODS One hundred fifty-four patients with intracranial aneurysms admitted to the Department of Neurosurgery, Showa University School of Medicine, from 1990 through 1996 were reviewed. The patients were classified by age into three groups (young group, middle-aged group, elderly group). RESULTS Forty-four patients (28.6%) were in the elderly group (mean age, 73 years). No difference in outcome was found between middle-aged and elderly patients if patients were stratified according to clinical grade. In addition, the main factors related to unfavorable outcomes in elderly patients were infection, organ failure, aneurysm rerupture before operation, and delayed ischemic deterioration. Elderly patients were more likely to experience rebleeding and have poor outcomes. CONCLUSIONS Our results suggest that elderly patients should have early surgery. Furthermore, we found that the presence of hypertension or atherosclerosis had no significant effect on outcome. We conclude that early surgical treatment of aneurysms is indicated for elderly patients with good clinical grades in the absence of organ failure.

Unsuccessful consequence of optic canal decompression for a case of craniometaphyseal dysplasia.

We have described a case of craniometaphyseal dysplasia in which decompression of bilateral optic canals for treatment of threatened damage of the optic nerve resulted in bilateral visual loss. We speculate that a specific mechanism exists whereby decompression of the optic canal can cause blindness.

Usefulness of bone window CT images parallel to the transnasal surgical route for pituitary disorders.

Summary. Objective: Before operating on 130 patients with pituitary disorders, we evaluated their bone window CT images sliced parallel to the transnasal surgical route to assess the surgical anatomy of the nasal cavity for transnasal surgery. Methods: High resolution bone window CT was performed in 3- to 5-mm slices parallel to the imaginary line connecting the inferior margin of the piriform aperture and the top of the sellar floor, parallel to the transnasal surgical route. Results: This CT angle was useful in evaluating the width and depth of the operative field, the bony components of the nasal conchas, deviation of the nasal septum, the bony structure and mucosa in the sphenoid sinus, and the condition of the sellar floor. In patients requiring repeat surgery, the location of thin or thick nasal mucosa, residual bony septum, and inadequate sellar floor opening were easily detected. Conclusion: Bone window CT images sliced parallel to the transnasal surgical route provide direct visualization of the nasal anatomy for the transnasal approach. This method is helpful in determining how far to remove the sellar floor laterally, especially in cases requiring repeat surgery.

Haemorrhagic Nonsecreting Pituitary Adenoma Associated with Persistent Primitive Trigeminal Artery

A 44-year-old man presented with headache of sudden onset and visual disturbance. There was no personal or family history of neurological disease. Physical examination revealed decreased libido, pale skin, sparse axillary hair, and erection disorder. Neurological examination was normal except for a bitemporal hemianopsia. Endocrinological examination showed panhypopituitarism. A sellar tomogram showed an enlarged sella turcica. A computed tomographic (CT) scan revealed an iso-density mass with ring enhancement in the intraand suprasellar lesion. Magnetic resonance (MR) imaging demonstrated an intraand suprasellar mass with intratumoural haemorrhage, and a vascular structure arising from the left cavernous carotid artery (Fig. 1). No anomalous vascular structure in the pituitary fossa was observed on CT scan and MR imaging. Cerebral angiography showed a persistent primitive trigeminal artery (PPTA) from the left cavernous internal carotid artery which supplied the posterior cerebral arteries, bilaterally, superior cerebellar arteries, and the distal basilar artery (Fig. 2). This tumour was preoperatively diagnosed as a haemorrhagic nonsecreting pituitary adenoma. The patient underwent urgent transsphenoidal surgery. Tumour tissue in the haematoma was subtotally resected. The PPTA was not found in the pituitary fossa. Histological examination showed a di ̈use type chromophobic pituitary adenoma and immunohistochemical study revealed a null cell adenoma. The postoperative course was uneventful. Acta Neurochirurgica > Springer-Verlag 2000 Printed in Austria Acta Neurochir (Wien) (2000) 142: 1423±1424

Role of 3D-TOF magnetic resonance angiography for intracranial meningioma

Three-dimensional (3D) time of flight (TOF) magnetic resonance angiography (MRA) was performed in 13 patients with intracranial meningioma. 3D-TOF unenhanced MRA depicted arterial displacement by tumour, and poorly demonstrated the sinuses, veins and tumour mass. The direct visualization of the venous abnormalities on 3D-TOF MRA was improved by the administration of contrast material. 3D-TOF enhanced MRA simultaneously depicted tumour enhancement, arterial and/or venous displacement, and dural sinus involvement by the tumour, all of which were in good agreement with findings on conventional cerebral angiography. However, MRA tended to poorly demonstrate the feeding arteries as compared to conventional angiography. Our results indicate that multiview 3D-TOF enhanced MRA non-invasively provides important information about the topographic relationship between tumour mass and the surrounding vasculature.