The suthors present the case of 4-month-old girl with a midline prepubic sinus extending from the skin overlying the pubis to the superior surface of the bladder, and continuing to the umbilicus via the median umbilical ligament. The distal portion of the exicised sinus was surrounded by concentric bundles of collagen and smooth muscle with minimal inflammatory infiltrates, which suggests a developmental origin. According to Stephens' classification, the sinus appears to be a variant of dorsal urethral duplication of Stephens type 3
Woo-Hyun Park et al. (1993). Prepubic dermoid sinus: Possible variant of dorsal urethral duplication (Stephens type 3). Journal of Pediatric Surgery, 28(12), 1610–1611. doi: 10.1016/0022-3468(93)90116-3