Exploratory laparoscopy is the standard of care for approaching a non-palpable, unilateral, undescended testis. However, exploring the scrotum first makes more sense if you analyse the literature (reference, reference, reference):
Only 26% of patients “really” need laparoscopy, whereas scrotal exploration would suffice for the other 74% of patients, based on the flowchart above. Avoiding an unnecessary laparoscopic exploration saves time and eliminates the small –but not zero– risk of a laparoscopic-access injury.
In prepubertal boys with a unilateral undescended testicle, a contralateral testicle measuring more than 1.8 cm in length is predictive of a non-viable testis. Conversely, the absence of contralateral compensatory hypertrophy (size less than 1.8 cm) suggests a viable testicle.
Conclusion
Based on the studies summarized above, to minimize unnessary laparoscopic or scrotal explorations:
- Start with scrotal exploration if the contralateral testis is > 1.8 cm.
- Start with laparoscopic exploration if the contralateral testis is <1.8 cm.