Color Doppler sonography of the prostate

The digital rectal exam (DRE), serum prostate specific antigen (PSA) level and transrectal ultrasound (TRUS) serve as the primary means of early detection of prostate cancer, but all have known limitations. Because of the low predictive value for the gray scale detection of prostate cancer with TRUS, attempts have been made to improve the diagnostic accuracy of TRUS by incorporating color Doppler imaging (CDI) into the standard examination. With CDI, the sonographer has the ability to investigate both normal and abnormal flow within the prostate gland. Recent studies have supported the ability of CDI to detect vascularity in tumors that otherwise were not detectable with conventional gray scale TRUS, which suggests the potential for increase tumor detection. In the following article the rationale behind the use of color Doppler, the normal Doppler features of the prostate gland, and the result of the published studies on the diagnostic accuracy of color Doppler in prostate cancer are analyzed. In addition, areas of future research interest are reviewed.