Early and Delayed Tc—99m Glucoheptonate Brain Scintigraphy: Are Routine Early Images Indicated?

Both early and delayed Tc-99m glucoheptonate brain images were evaluated in 859 patients in order to determine whether the early imaging with this agent is clinically useful. The results suggest that the early brain images are inferior to the delayed ones in detecting CNS lesions. Use ofboth, however, may help to differentiate skull or scalp abnormalities from true lesions of the brain. J Nuci Med 20: 287—290, 1979 Because of scheduling difficulties involved in 3-or 4-hr delayed brain scintigrams, several agents have been evaluated for their sensitivity in detect ing CNS abnormalities with immediate or early studies (1—3). The purpose of this study was to evaluate early or immediate brain images using Tc-99m glucohep tonate (TcGH), and to determine when the early series should be used to complement the delayed study. METHODS Fifteen to twenty mCi of TcGH were adminis tered as a bolus i.v. injection. Brain images were obtained 15-20 mm following the dynamic flow, and repeated 2-4 hr postinjection. An Anger cam era with a high-resolution low-energy collimator was used in all studies. Scan findings were com pared with those of angiography, surgery, pathol ogy, or clinical followup for at least 1 yr. At least two independent observers compared the early and delayed static images using subjective estimates of lesion-to-calvanal (scalp, skull, dura) ratio, as well as lesion size, in forming an opinion