UNDESCENDED TESTIS
Absence of Testis
1. Undescended Testis: Along the normal path, but not reached scrotum.
2. Retractile Testis: Hyperreflexic Cremaster
3. Ectopic Testis: Deviation from normal path of descent
Embryology
Genital ridge – intermediate plate mesoderm
Germ cells derived from yolk sac.
Leydig and Sertoli cells from mesenchyme underlying genital ridge.
Vas deferens formed by mesonephric duct
Descent of testes
Starts at 8th wk Reaches deep Inguinal ring by 3rd month Lies dormant upto 6th month Traverses Inguinal canal during 7th month Reaches Superficial ring by 8th month Reaches bottom of scrotum by 9th month
Why descend ?
Factors responsible for descent
Trans abdominal phase – mainly mechanical Increasing abdominal pressure Differential growth of body wall Pull by Gubernaculum
Trans Inguinal phase – Combination of hormonal and mechanical factors.
Testosterone – through CGRP Processus Vaginalis
Clinical FeaturesAbsence of testis in scrotum since birth
Hemiscrotum empty, hypoplastic
Testis may or may not be palpable along the path of descent.
70% of UDT are palpable, 30% non palpable.
Pathophysiology
Alteration of testicular structure Leydigs cells Germ cells Infertility Inguinal Hernia Torsion testis Malignancy Trauma Psychological
Investigations
If palpable- no investigations needed
Unilateral impalpable- no investigations needed, but USG is done by many
Bilateral impalpable- rule out Intersex if genitalia look abnormal.
Management
No surgical intervention till child is 1yr of age unless there is associated complication like hernia or torsion.
Surgery if testis has not descended by 1 yr.
Palpable testis
Unilateral - Orchidopexy
Bilateral – Orchidopexy in the same sitting.
Impalpable testis 30% of all UDT
45% are intra abdominal
20% canalicular
35% vanishing testis
< 1% anorchia
Laparoscopy
Blind ending vessels – terminate procedure
Vessels exiting internal ring – Inguinal exploration – orchidopexy / orchiectomy
Intra abdominal testis – Fowler Stephen procedure
Inguinal exploration
Look for testis / nubbin in the inguinal canal or blind ending vas & vessels
If canal is empty, open the deep ring and explore retro peritoneum up to lower pole of kidney
Orchidopexy
Groin incision
Divide gubernaculum
Herniotomy
Divide bands holding the vessels to lateral abd wall
Place the testis in extra dartos pouch
Fowler Stephen Procedure
Communication exists between testicular artery & artery to vas through small arterioles in the peritoneal fold between them.
If the testicular artery is ligated and this peritoneal fold kept intact, testis can get adequate blood supply from these collaterals.