Hypospadias


Select Disease:
A congenital condition where the tip of the penis is off shape and is wider. Hypospadias is an abnormality of anterior urethral and penile development in which the urethral opening is ectopically located on the ventrum of the penis proximal to the tip of the glans penis, which, in this condition, is splayed open. The urethral opening may be located as far down as in the scrotum or perineum. The penis is more likely to have associated ventral shortening and curvature, called chordee, with more proximal urethral defects. Hypospadias is a common birth defect and does not imply that there are other defects in the other organs. The treatment involves surgical repair.

The location of the abnormal urethral opening (meatus) classifies the hypospadias. Although several different classifications have been described, most physicians use the classification that was proposed by Barcat and modified by Duckett, which describes the location of the meatus after correction of any associated chordee. Descriptive locations include anterior (glanular and subcoronal), middle (distal penile, midshaft, and proximal penile), and posterior (penoscrotal, scrotal, and perineal). The location is anterior in 50% of cases, middle in 20%, and posterior in 30%; the subcoronal position is the most common overall.

Hypospadias is generally repaired for functional and cosmetic reasons. The more proximally ectopic the position of the urethral meatus, the more likely the urinary stream is to be deflected downward, which may necessitate urination in a seated position. Any element of chordee can exacerbate this abnormality. Fertility may be affected. The abnormal deflection of ejaculate may preclude effective insemination, and significant chordee can preclude vaginal insertion of the penis or can be associated with inherently painful erections. Although the most minor forms of hypospadias are physiologically insignificant, they too may merit repair based on the potential psychological stress of having a genital anomaly.

A complete patient history and physical examination is required to diagnose the condition.

Patient History
A thorough history and physical examination, including any history of a familial pattern of hypospadias, any past medical history or comorbidity, and a physical assessment focusing on the meatal location, glans configuration, skin coverage, and chordee is required. A history of infertility and treatment should also be documented, as in vitro fertilization (IVF) has been associated with a higher incidence of hypospadias.

Physical Examination
Although the diagnosis of hypospadias has been made using both prenatal fetal ultrasonography and MRI, the diagnosis is generally made upon examination of the newborn infant.

  • A dorsal hood of foreskin and glanular groove is evident, but, upon closer inspection, the prepuce is incomplete ventrally and the urethral meatus is noted in a proximally ectopic position. Rarely, the foreskin may be complete, and the hypospadias is revealed at the time of circumcision. If hypospadias is encountered during neonatal circumcision, after the dorsal slit has been performed, the procedure should be halted, and the patient should be referred for urologic evaluation.
  • Chordee may be readily apparent or discernible only during erection. Proximal hypospadias is commonly associated with a bifid scrotum and penoscrotal transposition, in which the rugated scrotal skin begins lateral to the penis rather than in its normal posterior origin.

The objective of treating hypospadias is to create a straight penis by repairing any curvature (orthoplasty), to create a urethra with its meatus at the tip of the penis (urethroplasty), to re-form the glans into a more natural conical configuration (glansplasty), to achieve cosmetically acceptable penile skin coverage and to create a normal-appearing scrotum. The resulting penis should be suitable for future sexual intercourse, should enable the patient to void while standing, and should present an acceptable cosmetic appearance.

Timing of surgery
Before 1980, hypospadias repair was performed in children older than 3 years because of the larger size of the phallus and a technically easier procedure. However, genital surgery at this age was associated with significant psychological morbidity, including abnormal behavior, guilt, and gender identity confusion.
In recent years, most physicians attempt to repair hypospadias when the child is aged 4-18 months, trending toward earlier intervention. This has resulted in improved emotional and psychological health. A benefit in wound healing with earlier repair has also been perceived and may have a basis in the reduced proinflammatory cytokine production noted at younger age.

Types of repair

  • After fully assessing the penile anatomy, the shaft skin of the penis is degloved to eliminate any skin tethering, and an artificial erection is performed to rule out any curvature. Mild-to-moderate chordee may be repaired by excising any ventral fibrous tethering tissue or by plicating the dorsal tunics of the corporal bodies, compensating for any ventral-to-dorsal disproportion. More severe chordee may require grafting of the ventral corporal bodies using synthetic, animal (small intestinal subunit), cadaveric, or autologous tissues (tunica vaginalis or dermal grafts) to avoid excessive shortening of penile length. On rare occasion, the urethral plate may be tethered and transection of the plate may be required, precluding the use of native urethral tissues for urethroplasty.
  • The urethra may be extended using various techniques. These techniques are generally categorized as primary tubularizations, local pedicled skin flaps, tissue grafting techniques, or meatal advancement procedures.
  • The tubularized incised plate (TIP) repair has become the most commonly used repair for both distal and midshaft hypospadias. This technique is a primary tubularization of the urethral plate, with incision of the posterior wall of the plate, which allows it to hinge forward. This creates a greater diameter lumen than would otherwise be possible, obviating the routine use of a flap or graft to bridge a short narrow segment of urethral plate.
  • The general concept that increasing the layers of tissue between the urethra and overlying skin coverage result in a lower likelihood of the later development of urethrocutaneous fistula has been supported by recent studies.Temporary urethral stents are a common adjunct to hypospadias repair and are felt to decrease the likelihood of fistula formation. Various different drainage tubes have been utilized for this purpose.
  • For repeat repairs after unsuccessful surgery for hypospadias when local tissues are unavailable, buccal mucosa has been used for urethral grafting. This tissue is well suited for this purpose because of its availability, characteristics that favor graft success, and its resilience to a moist environment. Urethral stents are generally used for bladder drainage while healing occurs in all but the most distal hypospadias repairs.

Steps of repair

  • Glans flaps are generally mobilized to cover the distal urethral repair, bringing the divergent ventral components to the midline and creating a more conical configuration. The excess dorsal skin is mobilized to the deficient ventral aspect of the penis for final skin coverage.
  • The repair of penoscrotal transposition is often performed as a staged procedure because the necessary incisions may compromise the vascular pedicle to skin flaps used in the primary urethroplasty. The repair of penoscrotal transposition is usually deferred at least 6 months to allow for adequate formation of collateral blood supply.
  • The repair of hypospadias is generally planned as a single-stage procedure, but excessive chordee (especially if transection of the urethral plate is required), poor skin availability, and small phallic size may be better approached in a staged manner. The chordee is repaired and the skin is mobilized to the ventral penile shaft during the first stage, and the urethroplasty and glansplasty are repaired after the first stage has completely healed.
  • Adjuvant hormonal therapy: Although no medical therapy for the correction of hypospadias is known, hormonal therapy has been used as an adjuvant treatment for infants with exceptionally small phallic size. Presurgical treatment with testosterone injections or creams, as well as HCG injections, has been used to promote penile growth, and some have reported improvement in chordee with lessening in the severity of the hypospadias. The fact that prepubertal androgen therapy may limit normal genital growth at puberty is a concern but has not been confirmed clinically.

Complications

  • Immediate postoperative concerns
  • Local edema and blood spotting can be expected early after repair and generally do not cause a significant problem.
  • Postoperative bleeding rarely occurs and is usually controlled with a compressive dressing. Infrequently, this requires reexploration to evacuate a hematoma and to identify and treat the source of bleeding.
  • Infection is a rare complication of hypospadias repair in the modern era. Skin preparation and perioperative antibiotics are generally used, and patients are often maintained on an antibiotic course until any stents are removed.
  • Long-term issues
  • Fistula: Urethrocutaneous fistulization is a major concern in hypospadias repair. The rate of fistula formation is generally less than 10% for most single-stage repairs but rises with the severity of hypospadias, approaching 40% with complex reoperative efforts. Fistulas rarely close spontaneously and are repaired using a multilayered closure with local skin flaps 6 months after the initial repair. After repair, fistulas recur in approximately 10% of patients.
  • Meatal stenosis: Meatal stenosis, or narrowing of the urethral meatus, can occur. A urethral stent prevents any problems initially, but a fine-spraying urinary stream that is associated with straining to void likely requires operative meatal revision.
  • Stricture: Urethral strictures may develop as a long-term complication of hypospadias repair. These are generally repaired operatively and may require incision, excision with reanastomosis, or patching with a graft or pedicled skin flap.
  • Diverticula: Urethral diverticula may also form and are evidenced by ballooning of the urethra while voiding. A distal stricture may cause outflow obstruction and may result in a urethral diverticulum. Diverticula can form in the absence of distal obstruction and are generally associated with graft- or flap-type hypospadias repairs, which lack the subcutaneous and muscular support of native urethral tissue. The redundant urethral tissue is generally excised, and the urethra is tapered to an appropriate caliber.
  • Hair in the urethra: Hair-bearing skin is avoided in hypospadias reconstruction but was used in the past. When incorporated into the urethra, it may be problematic and can result in urinary tract infection or stone formation at the time of puberty. This generally requires cystoscopic depilation using a laser or cautery device or, if severe, excision of hair-bearing skin and repeat hypospadias repair.

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