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GAURAV NAHARDNB UROLOGY
RESIDENT,MMHRC, MADURAI
UNDESCENDED TESTIS
INTRODUCTIONOne of the most common pediatric disorders of male
endocrine glands &
Most common genital disorder identified at birth.
Cryptorchidism:A greek word which means ‘hidden testis’Retractile- 60%Undescended- 35%Ectopic- 3%Ascending- <2%
HISTORICAL PERSPECTIVE
1786: Hunter first drew attention to the mechanism of descent.
1820: Rosenmerkal attempted the first surgical orchidopexy but,
1877: Annandale performed the first successful orchiopexy.
DEFINITIONSNormal scrotal position: positioning of
midpoint of the testis at or below midscrotum.
Undescended testis: absence of one or both testes in normal scrotal position.
Vanishing testes: present initially in development but are lost owing to vascular accident or torsion unilaterally (monorchia) or, very rarely, bilaterally (anorchia).
Agenesis: testis that was never present and therefore associated with ipsilateral müllerian duct persistence.
Congenital cryptorchidism: testes that are extrascrotal at birth.
Recurrent cryptorchidism is when testes descend spontaneously postnatally but subsequently return to a nonscrotal position.
Testicular ascent or acquired cryptorchidism : Testes are intrascrotal at birth but subsequently identified in an extrascrotal position .
Secondary cryptorchidism- testes that are suprascrotal after inguinal hernia repair; testicular retraction- as a complication of orchidopexy.
Retractile testes are scrotal testes that retract easily out of scrotum but can be manually replaced in a stable scrotal position and remain there at least temporarily.
EPIDEMIOLOGYCryptorchidism is one of the most common
congenital anomalies. 1% to 4% of full-term and 1% to 45% of
preterm male neonates.
a component of over 390 syndromes.
familial cluster is 3.6-fold overall, 6.9-fold if a brother is affected, and 4.6-fold if the father is affected.
ETIO-PATHOGENESISMultifactorial pathogenesis.Birth weight is the principal determining
factor, at birth to age one year, independent of the length of gestation.
Premature infants- 30%More common in low-birth-weight male
newborns, IUGR, and twin gestation.
• Testicular descent occur as a result of a complex interactions of hormonal and mechanical factors
Hormonal factors:TestosteroneDihydrotestosterone Mullerian-inhibiting Substance(MIS/AMH)HCGGenital branch of genitofemoral nerve which
secret CGRP (elaborated by testosterone)Non androgen–insulin like factor 3(INSL-3)
Mechanical factors
Shortening and traction of the gubernaculum testis.
Enlargement/elongation of processus vaginalis.Intra-abdominal pressure from increased visceral
size. Straightening of fetus.Resolution of physiological hernia.Enlargement of testes/growth of epididymis.Propulsive force of the developing cremasteric
muscle.
Testicular Descent
Testicular descent occurs in two phases- transandominal & transinguinal.
INSL3(Insulin-like 3, Leydig cell origin) & Testosterone- key hormones required for testicular descent.
Transabdominal descent involves differential growth of vertebrae and pelvis until 23 weeks’ gestation. Afterward facilitated by the development of the gubernaculum, processus vaginalis, spermatic vessels, and scrotum.
A normal hypothalamic-pituitary-gonadal (HPG)axis is a prerequisite for testicular descent.
Testosterone and its conversion to dihydrotestosterone (DHT) are also necessary for continued migration, especially during the inguinoscrotal phase.
Release of calcitonin gene-related peptide (CGRP) from genitofemoral nerve stimulates development and function of the gubernaculum.
Enlargement, distal detachment and migration of the gubernaculum are key events that facilitate and direct caudal movement of the testis
Intra-abdominal pressure also appears to play a role in testicular descent most significant during transinguinal migration to the scrotum, probably in conjunction with androgens and a patent processus vaginalis.
Transabdominal descent complete by 10 weeks.
Traverses inguinal canal between 20-28 weeks.
32nd week – emerges from superficial inguinal ring.
35-40th week –descends into the scrotum.Left testis descends before the right.About 96% of testes have descended at birth.
Nonsyndromic Congenital Cryptorchidism
Perinatal risk factors associated with cryptorchidism include prematurity, low birth weight/small for gestational age, breech presentation, and maternal diabetes.
Extrascrotal testes - much less likely to descend by 1 year of age (50%) than high scrotal testes defined as cryptorchid at birth.
Spontaneous descent is more likely and may occur later in premature Infants.
Syndromic Cryptorchidism
Undescended testes are frequently present in diseases associated with reduced androgen production and/or action, such as androgen biosynthetic defects, androgen insensitivity, Leydig cell agenesis, and gonadotropin deficiency disorders, AMH biosynthesis or receptor defects.
Most commonly bilateral.
Certain anomalies are associated with increased risk of cryptorchidism: Musculoskeletal, central nervous system( CNS), or abdominal wall/gastrointestinal defects include
Classic prune-belly (triad or Eagle-Barrett) syndrome;
Spigelian hernia & Umbilical herniaCerebral palsyArthrogryposisMyelomeningocele Omphalocele & GastroschisisImperforate anus Posterior urethral valveRenal and T10 to S5 spinal anomalies
Genetic Susceptibility
Polygenic & multifactorial.
Most probable mode of inheritance- autosomal dominant with reduced penetrance.
INSL3, its receptor, relaxin/insulin-like family peptide receptor 2 (RXFP2), HOXA10, and HOXA11-most likely candidate genes for human nonsyndromic cryptorchidism(mouse models).
Environmental Risk Factors
Exposure to antiandrogenic and/or endocrine-disrupting chemicals(EDCs) may contribute to cryptorchidism.
EDCs include phthalates, pesticides, brominated flame retardants, diethylstilbestrol, and dioxins.
A subset of boys with cryptorchidism have measurable abnormalities in pituitary and/or gonadal hormone secretion during infancy without syndromic endocrine dysfunction.
Lifestyle factors may also interfere with testicular descent and function via hormonal or nonhormonal effects; ex. smoking is associated with cryptorchidism.
Presentation & Diagnosis
75% to 80%- palpable and60% to 70% are unilateral;involvement of the right side is more common
overall but less frequent in series of nonpalpable testes.
8% of testes-abdominal, 63% canalicular, 24% prescrotal, and 11% in the superficial inguinal pouch or ectopic.
Clinical features
Most patients presents in infancy and around school age. A few present after puberty.
Absence of one or both testes
swelling in the groin (may be the testis or a hernia)
May present with attacks of pain in the groin due either to recurrent torsion of the testis or strangulation of an associated hernia.
HISTORY: should cover the following questions:
Has the testis ever been palpable in the scrotum?
Was the patient born prematurely?Has the patient undergone prior inguinal
surgery?Is or was the patient's mother on a
vegetarian diet? Was the patient fed soy formula during infancy?
What was the patient's birth weight?
PRENATAL HISTORY:Did the patient's parents used an assisted
reproductive technique?Did his mother receive hormonal treatment?Were there multiple gestations?
FAMILY HISTORY:Cryptorchidism HypospadiasIntersexualityPrecocious pubertyInfertilityConsanguinity
PHYSICAL EXAMINATION:Patient should be warm and relaxed for the
examination.Observation should precede the examination.Supine and, if possible, upright cross-legged
and standing positions.Abduction of the thighs contributes to
inhibition of the cremaster reflex.Document testicular palpability, position,
mobility, size, and possible associated findings such as hernia, hydrocele, penile size, and urethral position.
Palpable Testes
Undescended testes may be located along the line of normal descent between the abdomen and scrotum or in an ectopic position.
Ectopic: Superficial inguinal pouch(m.c.) Perirenal Prepubic Femoral Peripenile Perineal Contralateral scrotal
Gold standard for diagnosis remains careful examination of a child in several positions and confirmation of incomplete descent of the testis to a dependent scrotal position after induction of anesthesia.
Nonpalpable testes
When a testis is nonpalpable, possible clinical findings at surgery include:
1. abdominal or transinguinal “peeping” location (25% to 50%),
2. complete atrophy (“vanishing” testis, 15% to 40%), and
3. extra-abdominal location but nonpalpable due to body habitus, testicular size, and/or limited pts.’cooperation(10-30%).
Diagnosis of a vanishing testis requires documentation of blind-ending spermatic vessels in the abdomen, inguinal canal, or scrotum.
Endocrine evaluation in cases of suspected bilateral vanishing testis (anorchia) include elevated basal serum gonadotropin levels and no response to hCG stimulation.
Classification
A. Based on palpation (Kaplan-1993)Impalpable:High canalicularDeep inguinal ringIntra-abdominalAccounts for 20% of UDT.Palpable: Neck of scrotumSuperficial inguinal ringLow canalicularAccounts for 80% of UDT
Classification contd
B. Based on exploration findings: intra-abdominalintracanalicular extracanalicular (suprapubic or infrapubic), orectopic.
InvestigationImaging
Abdominal USSCT ScanMRIBecause imaging has not been proved to be
reliable in demonstrating whether the testis is present or absent, its routine use is discouraged
Laboratory InvestigationsKaryotyping↑ FSH- likely represent bilateral anorchiaHCG Stimulation tests- has clinical use
where gonadothrophins are normalFBC, Urinalysis, Serum electrolytes
Diagnostic Laparoscopy
Complications of Undescended testis
InfertilityAssociated herniao indirect inguinal hernia usually accompanies a
congenital undescended testis in about 90% cases but rarely symptomatic.
Testicular atrophy: due to pressure effects and histological changes.
Trauma
Tumour: o 10% of testicular cancer originate in cryptochid
testis.TorsionEpididymo-orchitis in a cryptorchid right
testis can mimic appendicitisPsychologic effects of an empty scrotumTesticular-Epididymal fusion abnormality
ASSOCIATED PATHOLOGY
TESTICULAR MALDEVELOPMENT:Reduced total germ cell count
Impaired transformation of gonocytes to spermatogonia.
Delayed disappearance of gonocytes & appearance of Ad spermatogonia.
ANOMALIES OF EPIDIDYMIS, PROCESSUS VAGINALIS & GUBERNACULUM:
Anomalies of fusion between the caput and/or cauda epididymis, elongation and/or looping, and atresia.
Failure of closure of processus vaginalis &
Aberrant lateral attachment of gubernaculum.
OTHER ASSOCIATED TESTICULAR ANOMALIESPolyorchidismSplenogonadal fusionTransverse testicular ectopia
TREATMENT
GOALS of treatment:to optimize testicular function,
potentially reduce and/or facilitate diagnosis of testicular malignancy,
provide cosmetic benefits, and
prevent complications such as clinical hernia or torsion.
Observation is indicated for the first 6 postnatal months to allow spontaneous testicular descent.
If descent does not occur in the postnatal period surgical treatment at 6 months of age.
Surgical treatment
Surgery remains the gold standard.
OrchidopexyShould be performed as early as 6months
because of rarity of spontaneous descent after
6mnths possible improvement in fertilityInterval of 6months in bilateral undescended
testes.
Principles of orchidopexy (originally described by Bevan in
1899)
Adequate exposureHerniotomyMobilization of cordFixation of testis
Orchidopexy for the palpable UDT
General anesthesia; useful to re-examine the child- previously nonpalpable testis may become palpable.
groin crease incision is made Careful dissection to expose the external oblique aponeurosis and the external ring.
The external oblique aponeurosis is opened in line with the fascia
Rolling the cord structures under a finger may help confirm the exact site of the canal.
Care inside the canal is taken to identify and preserve the ilioinguinal nerve.
The cord is isolated by sweeping the cremasteric fibres off it.
The gubernaculum is divided
Patent processus is dissected off the vas and vessels.
A high ligation of the hernia sac is performed, and the remaining structures are skeletonised
Manoeuvres to gain sufficient length include:Dissection of retroperitoneal attachments of the cord
.
Divide (or pass the testis under) the inferior epigastric vessels after opening the floor of the canal (transversalis fascia), allowing a more medial and thus direct route to the scrotum.(Prentiss manoeuvre).
Cranial extension of the incision.
Superficial scrotal incision
Skin separated from dartos muscle
The testis is placed in a sub-dartos pouch.Fixation sutures to the testes nolonger
recommended
Subdartos pouch
Impalpable UDTsLaparoscopy -best means of identifying intra-
abdominal testis, vas and vessels.
If laparoscopy indicates blind-ending gonadal vessels and vas deferens, the patient is said to have vanishing testis syndrome and no further action is necessary
Impalpable UDTs contdIf intra-abdominal testis identified, consider
staged orchidopexy or microvascular transfer.
If vas vessels seen entering inguinal canal, the groin should be explored.
The length of the gonadal vessels is the limiting factor to getting the intra-abdominal testis into the scrotum
Intra-abdominal testis
Options for intra-abdominal UDT
1. Standard inguinal orchidopexy(a high failure rate)
2. A two-stage Fowler-Stephens orchidopexy (open or laparoscopy).
The testicular artery is sacrificed. The rationale is that the testicular arterial supply
comes from three sources. At a 2nd stage (after 6 months of age, when
collaterals have formed), the testis is brought down on a wide pedicle of peritoneum containing the remaining vessels.
Options for intra-abdominal UDT contd
3. Microvascular testicular autotransplantation
employs microsurgical techniques.reserved for older children with internal
spermatic artery large enough to be anastomosed to inferior epigastric artery.
4. Refluo Testicular Autotransplantation
Provides only venous drainage by microvascular anastomosis of testicular veins to inferior epigastric veins
Based on discovery that failure in Fowler-Stephens was due to testicular congestion
Reduced operating time and increased success.
5. Jones Preperitoneal Approach
Preperitoneal cavity accessed by splitting abdominal obliques.
Testes mobilized transperitoneally and passed to the scrotum through the inguinal canal or posterior wall.
6. Orchidectomy :
Reserved for postpubertal men with a contralateral normally positioned testis.
Bilateral impalpable testis
Raise suspicion of an intersex condition.
Karyotype and hormonal profile should be characterized
Can involve measurement of MIS or an HCG stimulation test to detect the presence or absence of functioning testicular tissue.
Postoperative Complications
HaematomaInfectionUnsatisfactory position (requiring revision),Ilioinguinal nerve injuryDamage to the vasTesticular atrophyTorsion testis.
Outcome
Early orchidopexy may improve fertility
No evidence that it reduces risk of malignancy but allows early identification.
Thank You..