Cryptorchidism is a common disorder in pediatric urology. It has been observed to occur in 3% of term infants and 30% of premature infants; however, 75% and 90% of these undescended testes, respectively, will have spontaneously descended by age 1 year, leaving a true incidence of close to 1% (0.8%) of the male population. Ten percent of cases are bilateral, 3% of which will have one or both testes absent. The etiology is unclear, and although many genetically inherited diseases have a high association with cryptorchidism, most cases of the undescended testis are isolated with no evidence of a genetic component.
· A 33-fold increased risk of developing a testicular malignancy has been noted with undescended testes.
· Ten percent of testicular cancers arise in an undescended testis, 60% of which will be seminomas.
· The intraabdominal testis is four times more likely to undergo malignant degeneration than is an inguinal testis.
· Fertility is impaired. Only 30% of patients with bilateral cryptorchidism even after the surgery will be fertile. Spermatogenic damage appears to increase with higher position and longer periods of extrascrotal habitation.
· A high incidence of associated inguinal hernias (30%) occurs because of the patent processus vaginalis.
· An increased susceptibility to torsion exists, especially in postpubertal period.
· An increased susceptibity for trauma.
· Intraabdominal (10%)—testis is located proximal to the internal inguinal ring within the abdominal cavity.
· Inguinal canal—testis is located between internal and external intuinal rings.
· Ectopic—testis is located distal to the internal ring but outside its normal path of descent. Most are found in the superficial inguinal pouch or in perineum, femoral canal, suprapublic area, and, rarely, in the contralateral scrotal compartment.
· Absent testis (4%)—20% of nonpalpable testes are absent.
· Retractile testis—testis is not truly undescended. Its extrascrotal location is secondary to hyperactive contraction of the cremasteric muscle. It is commonly found in the prescrotal or low inguinal area and with gentle manipulation can be placed in the scrotum without tension.
Carefully palpate both scrotal compartments, the inguinal canals, perineum, suprapubic area, and femoral canal. A palpable testis will be inguinal, ectopic, or retractile. If the testis can be easily placed within the scrotum without tension, it is retractile. Note that the cremasteric reflex is most active between ages 2 and 7 years, making this diagnosis difficult. A nonretractile palpable testis is either inguinal or ectopic.
A nonpalpable testis is either intraabdominal, ectopic, inguinal, or absent. If both testes are impalpable, then measure serum testosterone response to human chorionic gonadotropin (HCG) stimulation (HCG 2,000 IU daily 3days) and basal follicle-stimulating (FSH) and luteinizing hormone (LH) levels. A negative testosterone response to HCG and elevated basal FSH and LH levels are reliable evidence of anorchism (bilateral testicular absence). Bilateral or unilateral non palpable nondescensus can be further investigated by ultrasound, computed tomography, laparoscopy, and surgical exploration. Most testes will be found at surgery close to the internal inguinal ring.
Why Treat Undescended Testis?
· The surgery will not reduce the malignancy occurrence chance but certainly it will make the testis more easily palpable for the patient and the surgeon.
· To repair inguinal hernias(30% patients have chance of co-existing hernia)
· To decrease risk of torsion
Therapy should be undertaken between ages 6 and 18 months. This will allow adequate time for spontaneous descent to occur and should minimize the potential complications of infertility and malignant degeneration. Retractile testes need no further therapy; however, periodic reexamination to confirm the diagnosis would be prudent. The truly undescended testes can be treated with either hormonal or surgical therapy or both.
HCG has been used to bring down the testis in up to 70% patients, respectively. Hormonal therapy is contraindicated with ectopic testes, in the setting of a hernia, and after prior orchiopexy or herniorrhaphy (because of the scarring).
Several different procedure for orchiopexy are effective, all based on the principles of adequate mobilization and fixation and repair of the associated hernia in one stage or in two stages.
Occasionally, greater mobilization of the proximal spermatic cord structures does not provide adequate length to allow for tension-free placement of the testis within the scrotum. Greater cord length can be obtained by mobilizing the spermatic vessels medially. The spermatic vessels are usually the limiting factor in these circumstances. The Prentiss maneuver was described in 1960 and is occasionally helpful in adding length to the spermatic vessels by positioning the spermatic vessels medially and thereby choosing the hypotenuse of the triangle, or the most direct course to the scrotum, created by the natural course of the vessels laterally through the internal ring. It is performed by incising the floor of the inguinal canal through the external ring and dividing the inferior epigastric vessels. The internal ring and transversalis fascia are then closed lateral to the cord.
Ligation of the testicular vessels occasionally becomes a necessary consideration, especially in the management of a high inguinal or intra-abdominal testis. The technique described by Fowler and Stephens was originally a one-stage procedure, but it may also be performed in two stages. If a one-stage repair is to be performed, it is critical early in the dissection that a wide pedicle of peritoneum be preserved with the vas deferens to maintain collateral blood flow.
Orchiectomy should be performed if the testis is atrophic and cannot be brought to the scrotum.