Classical (ectodermal ingrowth) and recently purported (endodermal differentiation) theories of distal glanular urethral development. (From Kurzrock EA, Baskin LS, Cunha GR: Ontogeny of the male urethra: Theory of endodermal differentiation. Differentiation 1999;64:115–122, with permission.)
Anatomically descriptive levels of hypospadias within the three major categories, based on the level of the meatus following orthoplasty.
Typical appearance of hypospadias. A , Dorsal “hood” foreskin (upper arrow) and distal glanular groove (lower arrow) . B , Ventral view of same patient showing paucity of foreskin and proximally placed meatus (arrow) .
Megameatus, intact prepuce (MIP) variant of hypospadias. A , Normal appearance of foreskin on lateral view. B , Sound passed within gaping hypospadiac meatus. C , Typical appearance of meatus following newborn circumcision in a patient with the MIP variant.
Obtener una cobertura cutanea satisfactoriamente desde el punto de vista cosmético
Artificial erection and tunica albuginea plication. A , Assessment for curvature after degloving of shaft skin, urethral plate intact. B , Neurovascular bundles isolated and elevated. Proposed parallel lines of incision bilaterally are opposite point of maximal curvature. C , Outer edges of incisions have been approximated, and both the intervening strip of tunica albuginea and the knots are buried. (Modified from Baskin LS, Duckett JW: Dorsal tunica albuginea plication (TAP) for hypospadias curvature. J Urol 1994;151:1668, with permission.)
. Second layer coverage of neourethra with subcutaneous (dartos) tissue flap harvested from lateral or dorsal penile shaft and repositioned ventrally over the neourethra. (From Retik AB, Borer JG: Primary and reoperative hypospadias repair with the Snodgrass technique. World J Urol 1998;16:186, with permission.)
Tunica vaginalis neourethral coverage. (Performed over mesentery of onlay island flap repair in this case.) A , Lateral border of onlay or tube pedicle may be advanced as a second layer of neourethral coverage. B , Testis to be delivered for harvest of tunica vaginalis as supplemental or sole source for second layer coverage. C , Harvest of tunica vaginalis. D , Isolation of flap from testis and distal spermatic cord. E , Tunica vaginalis has been secured over the neourethra. (From Retik AB: Proximal hypospadias. In Marshall FF [ed]: Textbook of Operative Urology. Philadelphia, WB Saunders, 1996, with permission.)
Intraoperative algorithm for hypospadias repair.
Ventral skin proximal to the hypospadiac meatus is evaluated for thickness/integrity prior to deciding on reparative technique. Note urethral sound passed into meatus. A , Thick, healthy skin overlying urethra (arrowheads) proximal to hypospadiac meatus. B , Thin, near transparent skin and urethra (arrowheads) proximal to meatus prior to midline incision. C , Same patient as in B following midline incision proximally from site of the native meatus (arrow) to the point of encountering healthy tissue in preparation for urethroplasty. Note catheter within neomeatus. The urethral plate has been outlined with incisions and marked in the midline with a longitudinal dotted line
Meatoplasty and glanuloplasty (MAGPI). A , Circumferential subcoronal incision is marked. B, Longitudinal incision, and C , transverse approximation (Heineke-Mikulicz procedure) of transverse glanular “bridge” in urethral plate. D , Ventral edge of meatus is pulled distally and medial glans “trimming” incisions are marked. E , Deep suture approximation of the glans. F , Superficial approximation of the glans and skin. (From Duckett JW: Hypospadias. In Walsh PC, Retik AB, Vaughan ED Jr, Wein AJ [eds]: Campbell's Urology, 7th ed, vol 2. Philadelphia, WB Saunders, 1998, pp 2093–2119, with permission.)