1. Department of Radiology, University of Minnesota Medical Center, Fairview, 420 Delaware St SE, B-226 Mayo Memorial Bldg, MMC 292, Minneapolis, MN 55455.
2. Department of Otolaryngology-Head and Neck Surgery, University of Minnesota Medical Center, Fairview, Minneapolis, MN.
3. Department of Pathology and Laboratory Medicine, University of Minnesota Medical Center, Fairview, Minneapolis, MN.