Magnetic resonance angiography: analysis of vascular lesions of the temporal bone and skull base.

Contrast-enhanced, high resolution, computed tomography (CT), along with gadolinium-enhanced magnetic resonance imaging (MRI), provide the skull-base surgeon with essential information for diagnosis and surgical planning. Evaluation of skull-base vasculature has traditionally been performed with angiography. Four-vessel angiography is an invasive procedure that subjects the patient to the potential risks of vascular injury, stroke, renal damage, anaphylaxis, and radiation. The development of gradient-recall echo pulse sequence in MRI provides a means to evaluate the vasculature with a noninvasive, low-risk technique. We review the experience of the House Ear Clinic with magnetic resonance angiography (MRA) in evaluating cranial-base abnormalities including paragangliomas, aberrant vessels, and dural sinus thrombosis. Based on a review of 25 cases, we conclude that MRA is a useful procedure for evaluation of major arteries, veins, and dural sinuses. The technique has been less helpful in defining small vessel detail such as feeding blood supply and tumor staining.