[Microanatomy of the female urethra]

The author presents a description of the microscopic anatomy of the bladder neck and female urethra based on reconstructions derived from microscopic sections performed in 3 planes. He describes the horizontal and vertical fibres. The horizontal fibres form 2 opposed, arched layers encircling the upper part of the bladder neck and derived from the detrusor. Inferiorly, there is a very small, annular, smooth muscle sphincter which surrounds the middle part of the urethra like a cuff. The vertical fibres arise from the detrusor mostly terminate in the periphery of the circular fibres. Several fibres also pass in the urethral lumen.