FEMALE PELVIC BONE-MARROW - SERIAL MR-IMAGING BEFORE, DURING, AND AFTER RADIATION-THERAPY

PURPOSE: To study early changes in irradiated pelvic and adjacent noni rradiated bone marrow with T1-weighted magnetic resonance (MR) and sho rt inversion time inversion-recovery (STIR) imaging. MATERIALS AND MET HODS: The bone marrow of 31 women with advanced cervical carcinoma was studied in 161 MR examinations before, during, and 7 weeks after radi ation therapy. Two radiologists visually evaluated the marrow signal i ntensity (MSI) on T1-weighted and STIR images. RESULTS: Changes in irr adiated and adjacent nonirradiated marrow were shown on T1-weighted im ages in 31 (100%) and 18 (58%) of the 31 patients, respectively. MSI c hanges on images were observed as early as 8 days after the start of r adiation therapy and occurred more frequently in irradiated than in ad jacent nonirradiated marrow. In the irradiated regions, a complete fat ty marrow was seen on T1-weighted images obtained 6-8 weeks after the start of radiation therapy in 28 (90%) of the 31 patients. CONCLUSION: T1-weighted and STIR images obtained during and soon after radiation therapy complement each other in showing changes in bone marrow.