Ophthalmologists are often the first clinicians to evaluate a patient harboring an underlying intraorbital or intracranial structural lesion. This unique position makes it particularly important for them to understand the basic mechanics, indications, and contraindications for the available orbital and neuroimaging studies (e.g., CT and MR imaging), as well as any special studies that may be necessary to fully evaluate the suspected pathology. It is equally important for them to be able to communicate their imaging questions and provide relevant clinical information to the interpreting radiologist. Since the publication of the original edition of this American Academy of Ophthalmology Monograph in 1992, new techniques and special sequences have improved our ability to detect pathology in the orbit and brain that are significant for the ophthalmologist. In this second edition of Monograph 6, Johnson, Policeni, Lee, and Smoker have updated the original content and summarized the recent neuroradiologic literature on the various modalities applicable to CT and MR imaging for ophthalmology. They emphasize vascular imaging advances (e.g., MR angiography (MRA), CT angiography (CTA), MR venography (MRV), and CT venography (CTV) and specific MR sequences (e.g., fat suppression, fluid attenuation inversion recovery (FLAIR), gradient recall echo imaging (GRE), diffusion weighted imaging (DWI), perfusion weighted imaging (PWI), and dynamic perfusion CT (PCT)). They have also included tables that outline the indications, best imaging recommendations for specific ophthalmic entities, and examples of specific radiographic pathology that illustrate the relevant entities. The goal of this Monograph is to reinforce the critical importance of accurate, complete, and timely communication-from the prescribing ophthalmologist to the interpreting radiologist-of the clinical findings, differential diagnosis, and presumed topographical location of the suspected lesion in order for the radiologist to perform the optimal imaging study, and ultimately, to receive the best interpretation.