1Department of Radiology, Dongguk University Il-san Hospital, Korea. 2Department of Radiology, National Cancer Center, Korea. pinksu77@hanafos.com
Published online: December 1, 2011.
ABSTRACT
PURPOSE: To describe the incidence of prostatic midline cysts in healthy men on transrectal ultrasonography. MATERIALS AND METHODS: From 2005 to 2009, 1,175 transrectal ultrasonography examinations were performed on 1,086 men (22-85 years) in a health promotion center. Incidence and size of midline cysts in men without any symptoms in the genitourinary tract were investigated according to age, prostate volume, and other ultrasonography findings. RESULTS: The incidence of midline cysts in healthy men was 28% (280/999). The mean diameter of midline cysts was 7.2 mm (1-30 mm). The incidence was the highest (32/102; 31.4%) and the size was the smallest (6.2 mm in mean) in men older than 60 years. The incidence of midline cysts in prostates larger than 20 ml was 33.2% (157/473) and in prostates smaller than or equal to 20 ml was 23.4% (123/526) (p < 0.05). Abnormal ultrasonography findings other than midline cysts were found in 196 men, and the incidence of midline cysts was high with seminal vesicle abnormalities (5/11; 45.5%). CONCLUSION: The incidence of prostatic midline cysts in healthy men on transrectal ultrasonography is higher than the result of previous studies. The incidence is higher in an enlarged prostate than in a prostate of normal size.