A new transverse-section brain imager for single-gamma emitters.

Physical and clinical data on a new emission transverse-section scanner are given. Comparative data from an earlier tomoscanner and a rotating gamma-camera system yield the following information for the three imagers. Resolution at the center of the field is 9 mm for this tomoscanner, 18 mm for the earlier tomoscanner, and 11 mm for the rotating camera; sensitivity (cps/muCi-ml) 36K, 15.4K, 1.9K; crystal area (cm2) 3096, 619, 490, respectively. The quantification of images is discussed. Clinical emission section scans of the brain, liver, chest and skull are presented and discussed. Forty brain scans were analyzed in conjunction with x-ray transmission tomography. No false positives were found. From a total of 15 lesions seen by the CT x-ray scanner, 14 were detected by the emission tomographic scanner, 12 by standard gamma-camera imaging. One false negative case (cyst) was seen by the transmission x-ray scanner but not by the emission scanner.