Use of the personal microcomputer for the analysis of clinical cardial PET studies acquired at the Paul Scherrer Institute in Villigen, Switzerland. At present this is the only PET facility in Switzerland. As the local computers were not usually available for image analysis, it was necessary to find a convenient way to visualize and analyze the PET images in our department in the Cantonal Hospital, Aarau (distance to Villigen some 30 km). The personal microcomputer is, as other authors have already shown, in fact capable of handling the acquired images (128 by 128 pixels) easily. We use a Macintosh IIcx (16 MHz Motorola 68030 CPU) as image analysis workstation. In spring 1990 we implemented a software which could read the original Siemens matrix file directly into the Macintosh PC. As the handling of this software was somewhat clumsy, we now use a very powerful software ("Explorer", UCLA), which is specially designed for PET analysis. Analysis of PET data on the personal computer saves both time and money as we are able to use a standard PC periphery, which is less expensive than specially designed medical units.