First Diagnostic Step for Undescended Testis
The first and most critical diagnostic step for undescended testis is a thorough physical examination to determine whether the testis is palpable or nonpalpable—this single clinical finding dictates all subsequent management, and imaging studies provide no additional diagnostic benefit. 1
Clinical Examination is Definitive
The 2025 EAU/ESPU guidelines are unequivocal: medical history and physical examination are key in evaluating boys with undescended testis, and localization studies using different imaging modalities usually provide no additional benefit 1. This represents the highest quality current evidence and should guide practice.
What to Look for on Physical Examination:
The examination must classify the testis as either:
- Palpable (can be felt along the normal path of descent)
- Nonpalpable (cannot be felt anywhere)
This distinction is critical because:
- Palpable testes proceed directly to standard orchidopexy 1
- Nonpalpable testes require laparoscopy for definitive diagnosis and treatment planning 1
Examination Technique:
Perform the examination in a warm room with the child relaxed. Examine from the external inguinal ring down to the scrotum, attempting to manipulate any palpable testis toward the scrotum. Distinguish true undescended testis from retractile testis (which can be manipulated into the scrotum and remains there temporarily).
Why Imaging is Not Recommended
The guidelines explicitly state that imaging modalities provide no additional benefit 1. This is reinforced by research evidence showing that ultrasound cannot reliably locate nonpalpable testes or change management decisions 2, 3. The "Choosing Wisely Canada" campaign specifically included avoidance of ultrasound in evaluating undescended testes 3.
Common Pitfall to Avoid:
Do not delay referral to obtain ultrasound or other imaging. This wastes time during the critical window for intervention (6-18 months of age) when germ cell loss is progressive 1.
Clinical Urgency
Once the diagnosis is made by physical examination:
- Referral should occur by 6 months of age (corrected for prematurity) 1, 3
- Treatment must be completed by 12 months, or 18 months at the absolute latest 1
- This timing is critical because histological damage (germ cell and Leydig cell loss) is already evident by 12-18 months 1
The rationale for early intervention is to preserve fertility potential and reduce malignancy risk—both directly impact long-term morbidity and quality of life 1, 2.
Re-examination Under Anesthesia
For nonpalpable testes, an important diagnostic step occurs intraoperatively: thorough re-examination under general anesthesia may identify a previously nonpalpable testis, which changes the surgical approach from laparoscopy to standard orchidopexy 1.