MR Image Contrast and Relaxation Times of Solid Tumors in the Chest, Abdomen, and Pelvis

Abstract
A retrospective study of 121 patients with tumors in the chest, abdomen, and pelvis was made to assess the degree of contrast between solid tumors and adjacent tissue on magnetic resonance (MR) spin echo (SE) images. Tumors examined were hepatomas (five patients), liver metastases (17), hemangiomas (seven), biliary carcinomas (eight), pancreatic carcinomas (five), renal tumors (15), adrenal tumors (eight), uterine tumors (17), bladder carcinomas (five), prostatic carcinomas (13), bone tumors (six), and lung carcinomas (15). A long repetition time (TR) and a long echo time (TE) were found the most useful to delineate tumors from liver, renal tumors from kidney, lung carcinoma from lung, pelvic tumors from muscle, and uterine tumors from the myometrium. A short TR and short TE provided the best contrast between tumors and fat and bone marrow. Therefore, for detection and staging of tumors, both a sequence with short TR and short TE and one with long TR and long TE are necessary. Pancreatic carcinomas were difficult to differentiate from liver and pancreas on all SE sequences used in the study. Contrast of adrenal tumors was independent of the sequence used. Some adrenal tumors were hypointense and some similar in intensity to the kidney. Further MR characterization of the tumors was limited. Index Terms: Spin echo–Nuclear magnetic resonance, techniques-Relaxation times-Nuclear magnetic resonance.