Yukari Takeyasu1, Takashi Nishii2, Tsuyoshi Murase1, Toshiyuki Shiomi1, Hisashi Tanaka3, Youichi Yamazaki4, Kenya Murase4, Hiroyuki Tanaka1, Jyunichi Miyake1, Hideki Yoshikawa1
1Department of Orthopaedic Surgery, Osaka University Graduate School of Medicine, Suita, Osaka, Japan; 2Department of Orthopaedic Medical Engineering, Osaka University Graduate School of Medicine, Suita, Osaka, Japan; 3Department of Radiology, Osaka University Graduate School of Medicine, Suita, Osaka, Japan; 4Department of Medical Physics & Engineering, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
In previous studies the cross-sectional area of CTS and median nerve were mostly evaluated on axial MR images, and there were few reports regarding sagittal MR images of the median nerve, presumably owing to difficulty in localization of the nerve. The present study showed that T2 abnormality was not correlated with morphological shape of the median nerve (flattening ratio), and was in accordance with the finding of Simon et al. Interestingly, localization of most abnormal T2 region in the median nerve differed among patients, in spite of generally accepted opinion that distal portion of the carpal tunnel is prone to entrapment. In conclusion, sagittal T2 mapping is feasible for identifying abnormal T2 region of the median nerve, presumably relating with nerve damage (swelling, edema, or disturbance of nerve fiber arrangements).