M H Sheu1, H Chiang, J H Wang, Y H Chang, C Y Chang. 1. Department of Radiology, Taipei Veterans General Hospital, and School of Medicine, National Yang-Ming University, Taiwan. mhsheu@vghtpe.gov.tw
Abstract
PURPOSE: The purpose of this work was to demonstrate signal changes of the prostatic urethra after transurethral resection of the prostate (TURP) on MR images and histopathologic correlation. METHOD: Sixty-three patients with prostate cancer confirmed by either TURP (Group A, 19 patients) or transrectal biopsy (Group B, 44 patients) were evaluated by endorectal MRI before radical prostatectomies. The MR images of postcurettaged prostatic urethras were correlated with the histopathologic features. RESULTS: On the T2-weighted images, a thin zone of hypointense signal surrounding the curettaged prostatic urethra was identified in 52.6% (10/19) of Group A patients, imaged soon after (mean 21.1 days) TURP, but was indiscernible in Group B patients and the other Group A patients, imaged later after TURP (mean 49.2 days). This hypointense signal zone histopathologically correlates with a zone of inflammatory tissue reaction surrounding the widened urethra. CONCLUSION: Inflammatory tissue reaction surrounding curettaged prostatic urethra after TURP accounts for the presence of a low signal zone on T2-weighted images.
PURPOSE: The purpose of this work was to demonstrate signal changes of the prostatic urethra after transurethral resection of the prostate (TURP) on MR images and histopathologic correlation. METHOD: Sixty-three patients with prostate cancer confirmed by either TURP (Group A, 19 patients) or transrectal biopsy (Group B, 44 patients) were evaluated by endorectal MRI before radical prostatectomies. The MR images of postcurettaged prostatic urethras were correlated with the histopathologic features. RESULTS: On the T2-weighted images, a thin zone of hypointense signal surrounding the curettaged prostatic urethra was identified in 52.6% (10/19) of Group A patients, imaged soon after (mean 21.1 days) TURP, but was indiscernible in Group B patients and the other Group A patients, imaged later after TURP (mean 49.2 days). This hypointense signal zone histopathologically correlates with a zone of inflammatory tissue reaction surrounding the widened urethra. CONCLUSION: Inflammatory tissue reaction surrounding curettaged prostatic urethra after TURP accounts for the presence of a low signal zone on T2-weighted images.