Fig. 1Higher magnification of major structures at and around the vaginal atresia (five squares from
). (A) shows the urethral rhabdosphincter (external sphincter). (B) shows the external orifice of the urethra with hypertrophied squamous epithelium. (C) shows a sandwiched area of the transient zone between the columnar and squamous epithelia (arrow heads). (D) shows hypertrophied squamous epithelium covering a short longitudinal septum of the lower vagina. (E) shows a thick subcutaneous tissue closing the vestibule that contains smooth muscle-like fibers. (F) shows an area immediately lateral to the vestibular bulb. The arrow in (F) indicates the lateral end of a recess of the vestibule. (A–D) were at the same magnification, and (E and F) were at the same lower magnification. Scale bars: (A–F) 1 mm. BSM, bulbospongiosus muscle; EAS, external anal sphincter; IAS, internal anal sphincter; ICM, ischiocavernosus muscle.