| Popis: |
In this chapter we summarise the main conclusions of this book. Testicular descent has evolved only in mammals and in modern mammals and humans it occurs in 2 separate steps, with different anatomy and hormonal control. The first step occurs when the developing testis produces insulin-like hormone 3 (INSL3) to make the gubernaculum swell. This holds the testis near the groin as the fetus grows. In the second step androgens masculinise the genitofemoral nerve, which controls gubernacular migration to the scrotum. Undescended testes (UDT) can be classified into congenital and ‘acquired’ with ‘retractile’ testes forming a grey zone between descended testes and those developing into ascending, acquired UDT. The effects of UDT are secondary to the high temperature of the maldescended testis, although some have a primary hormonal anomaly. Because of key germ cell development in the first year, orchidopexy should be done between 6 and 12 months of age, while surgical treatment of acquired UDT remains controversial. Standard orchidopexy is required for a palpable UDT and laparoscopy for intraabdominal, impalpable UDT. Hormone treatment remains controversial. It has little role to cause descent, but may have a role as an adjunct to surgery to improve germ cell function. The long-term prognosis remains uncertain, but is predicted to improve with early surgery compared with the past. |
