Comparison of Nuclear Magnetic Resonance Microimages and Histology of Rat Ovaries.

Abstract

Nuclear magnetic resonance (NMR) microscopy is a magnetic resonance imaging technique with an enhanced spatial resolution. In this study, fresh ovaries of mature rats immersed in phosphate buffered saline (PBS) were examined by NMR microscopy. Histological sections corresponding to NMR microimages were prepared, and components in ovaries were identified in microimages by comparison with light microscopic images. Signal intensities of antral follicles, corpora lutea (CL), stroma, adjacent fat tissue and PBS were measured in images with different echo times (TE) and analyzed. As TE increased, signal intensities decreased in CL and connective tissue including the stroma, while those in PBS and follicles changed less. Fat showed significantly high signals compared with other components at each TE. Stroma showed significantly low signals than other components except PBS and follicles at TE of 5 msec. There were no significant differences among CL, follicles and PBS at TE of 5 msec. At TE of 20 msec, however, there were significant differences in signal intensities between each components in the rank order fat > PBS > follicles > CL > stroma. Significant regression of signal intensity was seen on TE in follicles, CL and stroma. NMR microscopy is considered to be a useful tool to investigate the physiological function of rat ovaries.