Factors affecting testicular volume after orchiopexy for undescended testes

Children with undescended testes (UDTs) undergoing orchiopexy at a later age reportedly experience more negative effects on post-orchiopexy testicular volume (TV). This study aimed to investigate the effect of orchiopexy according to the age at operation.

We included 93 patients (127 testes) who underwent orchiopexy between 2008 and 2020. According to their age at orchiopexy, they were divided into Group 1 (< 24 months; n = 36, median follow-up: 17 [14-39] months) and Group 2 (≥ 24 months; n = 57, median follow-up: 16 [13-34] months). TV was measured with ultrasonography preoperatively and postoperatively. In unilateral UDTs, the testicular volume rates (TVR) were calculated as diseased-side TV/intact-side TV × 100%. A TVR < 50% indicated preoperative testicular atrophy (pre-op TA), whereas volume loss ≥ 50% from baseline indicated postoperative testicular atrophy (post-op TA).

Only seven patients experienced pre-op TA. The TV of these 14 atrophic testes improved after orchiopexy (TVR: 100% (7/7) in Group 1 and 85% (6/7) in Group 2). Furthermore, the median TVR significantly improved after orchiectomy, from 27 to 58% (p < 0.01) and from 32 to 61% in Groups 1 and 2 (p < 0.05), respectively. Post-op TA was found in four testes (8%) in Group 1 and three testes (4%) in Group 2. Multivariate analysis showed that only preoperative testicular location predicted post-op TA.

Post-orchiopexy TA may occur regardless of the patient's age at orchiopexy, and orchiopexy is recommended irrespective of age at diagnosis.