ABSTRACT
A new method utilizing computer subtraction allows 2 separate radionuclide angiograms to be performed during a single laboratory visit. Two separate intravenous injections of the radionuclide are given so that the patient's head can be imaged in 2 different projections. Background activity from the first injection is subtracted by the computer to allow good resolution of blood flow following the second injection. A static brain scan is performed after the second injection. Although single-view radionuclide angiography is widely used in the diagnostic evaluation of the brain, the addition of a second projection provides additonal important diagnostic information. The views obtained, however, must be determined individually for each patient on the basis of the clinical history and neurologic signs. The selection of appropriate views, the diagnostic quality of the studies, and the practical clinical application of this technique are illustrated by 2 case reports.
Subject(s)
Brain/diagnostic imaging , Cerebrovascular Disorders/diagnostic imaging , Adult , Aged , Cerebral Angiography , Computers , Female , Humans , Male , Methods , Radionuclide Imaging , TechnetiumABSTRACT
Abnormal distribution of cerebral vascular flow was studied in a patient who had a traumatic carotid-cavernous sinus fistula. Serial studies were performed using a method for determining relative cerebral vascular flow:99mtechnetium-diethylenetriamine pentaacetic acid (99mTc-DTPA) was injected intravenously and flow data were processed by a digital computer. Serial studies documented the occurrence of a vascular "steal" during temporary carotid occlusion; postoperative studies showed disappearance of the steal and obliteration of thiling arterial structures and capillary filling in the brain, and in demonstrating alteration in the cerebral circulation.
