T el Gammal

Early bilateral radiation-induced optic neuropathy with follow-up MRI.

Most documented cases of radiation-induced optic neuropathy are unilateral and occur more than 1 year after radiotherapy to the sellar region. We describe a patient with bilateral radiation optic neuropathy 3 months following the completion of radiotherapy. MRI 13 months after the onset of visual failure showed bilateral optic atrophy with residual gadolinium enhancement.

MR of uncommon congenital and vascular lesions of the intracranial visual pathways

SummaryThe MR findings of two patients with rare congenital abnormalities of the optic pathways are reported and illustrated, including one case of unilateral aplasia of the optic chiasm, tract, and visual radiations and another patient with anophthalmos. In three other patients with unusual vascular causes of visual disturbance, MR was important in early establishment of an accurate diagnosis and had consequent implications for decisions regarding further patient management.

Gadolinium-enhanced MRI of the intracranial visual pathways

MRI with gadolinium (Gd) showed abnormal enhancement in the optic nerves and/or chiasm and tract in three patients with multiple sclerosis and three with neurosarcoidosis. Postoperative enhancement in the chiasm was seen in two patients, possibly due to postsurgical inflammatory reaction. Gd increases the sensitivity of MRI in demonstrating involvement of the optic nerves and intracranial optic pathways in inflammatory diseases and systemic disease with suspected visual pathway involvement.

MRI of the displaced and distorted optic chiasm and adjacent visual pathways

The MRI features of chiasmal and adjacent visual pathway displacement and distortion have not been emphasized to date. We have retrospectively studied 58 patients to compare and contrast the frequency and appearance of the morphologic changes and the presence or absence of consequent visual disturbances. This material included 9 mass lesions (6 neoplasms and 3 aneurysms) and other non-neoplastic lesions: 15 cases of severe hydrocephalus, 14 of advanced primary empty sella turcica and 20 of secondary empty sella and leptomeningeal inflammation. There was a general correspondence of anatomic change and abnormal ophthalmologic examination in patients with mass lesions. There was no correlation of visual disturbances with anatomic abnormalities found in the non-neoplastic group.