NMR of the normal and pathologic eye and orbit

Nuclear magnetic resonance (NMR) images of the eye and orbit were reviewed in a series of 100 normals and in four patients with orbital or ocular pathology. A rich retrobulbar fat content rendered the orbit well suited for NMR imaging. The lens, vitreous, optic nerve, and extraocular muscles were well visualized with spin-echo technique. However, NMR spatial resolution was inferior to that of high-resolution computed tomography (CT). NMR was comparable to CT in demonstrating choroidal melanoma and orbital pseudotumor. NMR exhibited a particular sensitivity in displaying tissue contrast for infiltrative orbital fat lesions with a relatively long T1. This initial experience suggests a promising role for NMR in orbital imaging.