Robert A. Nugent

Optic nerve sheath meningiomas.

PURPOSE To study the natural history and growth of optic nerve sheath meningiomas and evaluate their management outcome. DESIGN Clinicopathologic retrospective noncomparative case series. METHODS A retrospective study of 88 patients who were treated between 1976 and 1999 at the University of British Columbia and the University of Amsterdam. Clinical reports, imaging studies, and histopathologic findings were reviewed. RESULTS The mean age at onset of symptoms was 40.3 years, and most were seen in middle-aged females. Patients typically presented with visual loss, frequently associated with optic atrophy or papilledema and occasionally optociliary shunt vessels. On imaging, the optic nerve demonstrated segmental or diffuse thickening of the sheath or globular growth. Calcification was seen in 31% of cases and was associated with slower tumor growth. Tumors with posterior components in the orbit had more frequent intracranial involvement. Intracranial extension was more frequent and had a greater growth rate in younger patients. Irregular margins in the orbit implied local invasion. A presenting visual acuity better than 20/50 correlated with longer preservation of vision. Patients who underwent radiotherapy showed improvement in their visual acuity, and tumor growth was halted. Optic sheath decompression did not preserve vision. En bloc tumor excision was associated with no detectable recurrence in contrast to debulked tumors that recurred. CONCLUSIONS Meningiomas show characteristic indolent growth. Management therefore should be conservative in most cases. Radiotherapy is indicated in patients with progressive visual deterioration. Surgery, when indicated, should be an en bloc excision.

The Classification and Management of Acute Orbital Pseudotumors

The clinical presentation, investigative findings, classification, and management of 17 acute pseudotumors based on patterns of orbital involvement is presented. Acute pseudotumors developed over days to weeks and were dominated by pain, neuropraxia, and inflammatory clinical features. Five patterns of acute inflammatory pseudotumor were seen. Anterior and diffuse acute pseudotumors were characterized by manifestations of inflammation of the globe and orbit including pain, lid swelling, ptosis, diplopia, uveitis, papillitis, optic neuropathy, and exudative retinal detachment. Anterior or diffuse orbital infiltration was noted on computerized tomography (CT) and ultrasound. Lacrimal involvement was characterized by local pain, tenderness, lid swelling and inflammation, with CT and ultrasound confirming an anterior inflammatory mass. Posterior or apical involvement led to an early optic neuropathy, and myositic lesions were characterized by features of muscle infiltration. Management with steroids was effective and could be followed by serial CT studies.

Computed tomography of anterior inferior cerebellar artery aneurysm mimicking an acoustic neuroma.

Twenty-one previously reported cases of aneurysms of the anterior inferior cerebellar artery (AICA) were reviewed. They often present acutely with subarachnoid hemorrhage due to rupture, or less frequently with an insidious onset, as a cerebellopontine angle (CPA) mass. Rupture of the aneurysm is usually not difficult to diagnose because of the acute symptoms and the subarachnoid hemorrhage, which can easily be detected by CT or lumbar puncture. However, caution must be exercised in those lesions presenting as a CPA mass clinically, which on CT appear unusually dense with contrast enhancement. Erosion of the internal auditory canal may be present but is non-specific. If an enhancing CPA mass appears atypical and dynamic CT confirms rapid enhancement, vertebrobasilar angiography is essential to establish an AICA aneurysm as the cause.

Cerebral infarction and regression of widespread aneurysms in Kawasaki's disease: case report.

The prevalence of Kawasakis disease has increased in the last decade and it is now recognized worldwide. Coronary aneurysms are an important complication often causing death. The widespread vascular changes which can occur are illustrated by a patient who presented with a cerebral infarct and who developed widespread aneurysmal disease which regressed.

Case Reports, Arachnoid Cysts with Orbital Bone Remodeling——Two Interesting Cases

Purpose: To describe two cases of arachnoid cyst that altered the bony orbit. Methods: Case report. Results: Cases of unilateral arachnoid cyst are described in two men, both over the age of 60. The patients were evaluated with computed tomography (CT) scans and in each, an arachnoid cyst in the middle cranial fossa caused bone remodeling with exophthalmos in one. These patients were followed clinically and radiographically over a number of years with no change. Conclusion: Arachnoid cysts in the middle cranial fossa have the potential to result in clinically significant proptosis due to bone remodeling of orbital walls. Patients with unexplained proptosis should be evaluated with CT scans to establish the presence of bone remodeling and an arachnoid cyst, which can be confirmed with T2-weighted magnetic resonance imaging (MRI).

Computed tomography of calvarial and petrous bone sarcoidosis

This report describes the radiographic features in a case of sarcoidosis involving both the frontal calvaria and the petrous bone. The plain radiographic and nuclear medicine findings were consistent with previous descriptions. High resolution CT demonstrated concentric growth with a lucent advancing margin, ghost-like remnant of partially replaced bone, crossing of suture lines, invasion of contiguous bones, and lack of associated soft tissue mass.