1. Impalpable Testes Molly Eng Teaching session 16 Feb 2004

2. Definitions Cryptorchidism – “ hidden testis” a developmental defect in which there is failure of the testis to descend into the scrotum Other terminology Ascended testis Gliding testis Retractile testis Ectopic testis True undescended testis

3. Embrology Testicular Development Sex determining gene on short arm of Y chromosome Germ cell development under influence of fetal pituitary gonadotropins (up to 8 weeks gestation) Testosterone and Mullerian inhibitory substance Testicular Descent From internal inguinal ring into scrotum Masculinization of the inguinal canal ( 15-24 th wks) Transinguinal descent ( 24-28 th wks)

4. |Aetiology Abnormal or poorly timed androgen secretion Malformation or anatomic obstruction of the inguinal canal Abnormal develoment of the gubernaculum, processus vaginalis or abdominal wall. Low birth weight, prematurity and hypospadia associated with increase risk Familial, multifactorial chromosomal defect

5. Incidence Incidence decreases from 3.4% in full term infants to 1% at 3 months of age In infants with persistent undescended testes, 1/3 will be bilateral and 2/3 will be unilateral, often right (x2) AgeWeight(g)Incidence (%) Premature451-910100 Full term2491-272012 One year0.7-0.8 School age0.76-0.95 Adulthood0.7-1.0 Scorer and Farrington 1971

6. Classification Palpable or nonpalpable Kaplan 1993 Cryptorchid testicular position Intra-abdominal Intracanalicular Extracanalicular (suprapubic or infrapubic) Ectopic Anorchia (vanishing testis)

7. Diagnosis Approx. 20% of undescended testes are impalpable on initial examination 60% present and 40% absent or associated with fibrous tissue and haemosiderin History and Examination Genetic karyotyping Imaging Human chorionic gonadotropin hormonal stimulation Measurement of serum mullerian inhibitory substance

8. Investigations Localization of impalpable testicle Ultrasonography Computed axial tomography and magnetic resonance imaging Laparoscopy

9. Management Algorithm Impalpable testes Ultrasound positive Inguinal orchidopexy Inconclusive CT/MRI Canalicular vanishing testes Canalicular testes Intraabdominal testes Inconclusive Inguinal exploration Inguinal orchidopexy Laparoscopic- assisted orchidopexy Laparoscopy ? Intraabdominal vanishing testes

10. Management Hormonal therapy GnRH – Hadziselimovic 1984 hCG – Polaschik 1996 Orchidopexy Laparoscopic orchidopexy Diagnostic and therapeutic – Radmayr et al JUrol 2003 Fowler-Stephens orchidopexy One or two stage depending

11. Others Fertility issues Association with testicular malignancy 4-7 fold increase risk Position theory Common cause theory- common cause for both testicular neoplasia and cryptorchism