This volume contains the proceedings of the thirteenth biennial International Conference on Information Processing in Medical Imaging (IPMI XIII), held on the campus of Northern Arizona University in Flagstaff, Arizona, in June 1993. This conference was the latest in a series of meetings where new developments in the acquisition, analysis and utilization of medical images are presented, discussed, dissected, and extended. Today IPMI is widely recognized as a preeminent international forum for presentation of cutting-edge research in medical imaging and imageanalysis. The volume contains the text of the papers presented orally atIPMI XIII. Over 100 manuscripts were submitted and critically reviewed, of which 35 were selected for presentation. In this volume they are arranged into nine categories: shape description with deformable models, abstractshape description, knowledge-based systems, neural networks, novel imaging methods, tomographic reconstruction, image sequences, statistical pattern recognition, and image quality.