Subtraction, photographic method which cancels out bone shadows that obscure vascular details, is valuable adjunct to standard angiographic techniques. Vertebral angiography via catheter approach is useful in evaluating atypical cerebellopontile angle masses, vascular lesions, and meningiomas. Displacement of anterior inferior cerebellar artery, usually posteriorly and upward, is earliest angiographic feature of cerebellopontile angle masses. Elevation, lateral displacement, or nonfilling of petrosal vein may be observed. Carotid angiography, preferably with selective external carotid injections, is indicated to diagnose and localize glomus tumors. © 1973, American Medical Association. All rights reserved.