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.