Purpose, and Material and Methods: MR findings of 9 surgically proven tubo-ovarian abscesses were analyzed in 8 patients. The images were evaluated for signal intensity characteristics and morphologic appearance of the mass, and presence of secondary changes in adjacent pelvic organs and structures. Results: The signal intensity of the lesions on TI-weighted images was hypointense to the surrounding muscle and myometrium in 5 patients, isointense in 3,and hyperintense in 1. On T2-weighted images the signal intensity was hyperintense (n=6) or heterogeneous (n=3). A thin rim (1-3 mm) with hyperintensity on T1-weighted images was noted in the innermost aspect of the masses. Other findings were ill-defined margin, thickened wall, multiple internal septa, shading and gas collection. "Mesh-like" linear strands were noted in the pelvis in all patients, with involvement of adjacent pelvic organs in 7 and lymphadenopathy in 3. Conclusions: In this limited number of cases MR imaging showed great potential for demonstrating the extent of the disease, characterizing the lesions and making a specific diagnosis.