The anatomic basis of the anterior vaginal flap used for neourethra construction in female-to-male transsexuals.

For lengthening of the urethra in female-to-male transsexuals, an anterior vaginal wall flap is used. This flap is separated from the posterior urethral wall down to the attachment at the urethral meatus following a glistening cleavage plane. In this paper we present the anatomic and histologic basis of this flap. Prior to this, the relevant vaginal anatomy will be discussed. The anterior vaginal wall and posterior urethral wall are not indissectible structures; this is true even in the caudal two-thirds of the urethra. A long and narrow flap can be raised, thanks to the abundant vascular supply of the vaginal wall and the musculomucosal quality of the flap. A previously performed anatomic and histologic survey of the anterior vaginal wall has shown that the glistening cleavage plane is not composed solely of fascia, but rather consists of longitudinal strands of muscle, fibrous tissue, and elastin.