Anatomical explanations of the pathogenesis of proximal hypospadias

Abstract

Aims:The aim of this study was to try to explain the pathogenesis of proximal hypospadias based on anatomical and histological findings.Methods:During 9 years, we performed systematic biopsies (in the lateral areas of the urethral plate, as well as under this plate) in 81 patients treated for proximal hypospadias. The histological study was performed by routine coloring, hematoxylin and eosin, and Masson's trichrome, which colors the collagen fibers in blue, and monoclonal antibody against alpha-smooth muscle actin.Results:There is a fibrosis tissue abnormally present on the ventral side of the penis. This tissue consists of a mixture of fibrous connective tissue, nerve nets, short vessels, and smooth muscle fibers. The penis' dartos does not contain smooth muscle fibers. These fibers can come from a blood vessel or spongy tissue which existed during the neonatal period in the distal part of the penis before disappearing.Conclusions:The proximal hypospadias is due presumably to avascular necrosis of the distal part poorly vascularized of the corpus spongiosum.

Effects of spongioplasty on neourethral function following hypospadias repair: an experimental study in rabbits

“…Subsequently, there have been many reports of the use of bifurcated spongiosum (alone or in combination with other tissue layers) as a healthy intermediate tissue layer for use in urethroplasty. It is well-vascularized, robust, and can be conveniently harvested, it is also considered to be physiologically appropriate for use as a protective layer of the neourethra, such that it may aid in the natural propulsion of urine and semen (2,15,16). Spongioplasty can reduce suture tension during urethroplasty, and increases the tissue thickness of the ventral penis, thus helping to reduce fistula rate (17).…”