Neuroimaging contrast agents in ophthalmology

Magnetic resonance (MR) imaging and computed tomography (CT) ale routinely performed with the use of contrast materials in the diagnosis of neuro-opht halmologic disease. Iodinated agents are commonly used in CT scanning and f emoral contrast arteriography, and gadolinium is used in MR imaging. While contrast materials contribute greatly to diagnostic accuracy, they may also be responsible for adverse effects, ranging in severity from mild discomfo rt to death. The most frequent and severe side effects are associated with ionic iodinated contrast agents, while the rate of adverse reactions is les s with use of nonionic iodinated contrast agents. Side effects and adverse reactions to gadolinium are uncommon, but they do occur. In neuro-ophthalmo logic diagnosis, MR imaging is generally preferred over CT scanning, partly because of its greater ability to delineate soft tissue intracranial struc tures, but also because of the relative safety of gadolinium as a contrast agent. Properties of contrast agents are discussed in the context of specif ic imaging techniques and tissues investigated. Types and severity of adver se effects as well as risk factors for incurring such effects are summarize d. (Surv Ophthalmol 45:237-253, 2000. (C) 2000 by Elsevier Science Inc. All rights reserved.).