Anatomic features of the eye disclosed with nuclear magnetic resonance imaging

Nuclear magnetic resonance (NMR) imaging of the eye and paraorbital areas was performed in 35 volunteers and in four patients with ocular pathology. Two- and three-dimensional images were performed with saturation recovery (SR), inversion recovery (IR), and spin echo (SE) pulse sequences. Fat was brighter than surrounding tissue on images obtained with all pulse sequences, while muscle and optic nerve were of decreased intensity. The optic chiasm and vitreous were of decreased intensity compared with orbital fat on SR. The lens had even less signal intensity than the vitreous on SR and IR images and blended into the surroundings on SE images. A melanoma of the ciliary body and a lymphoma of the lacrimal gland were identified. In conclusion, NMR images can be used to identify normal and pathologic orbital and eyeball anatomy. Image contrast is provided by high intensity fat, which is interspersed throughout other orbital structures.