The usefulness of testicular atrophy index in the assessment of undescended testicle--preliminary report.

PURPOSE Cryptorchidism affects 2-8% of male newborns. There is a controversy regarding timing of surgery as well as indications for orchiopexy in boys with retractile testicle. The aim of this study was to evaluate the clinical usefulness of testicular atrophy index (TAI) as a criterion of qualifying patients with undescended testes for surgery as well as of monitoring the results of treatment. MATERIAL AND METHODS In 1999-2000, 105 cryptorchid boys, aged 1 to 15 years (mean 4.8) underwent unilateral orchiopexy. Dimensions and volume of testes were measured by means of scrotal US and TAI was calculated before and 1 year after surgery. RESULTS Pre- and postoperative scrotal US measurements were analyzed in 35 boys divided into five age dependent groups. The preoperative TAI values ranged from 27.1% to 52.8%. The biggest loss in volume of affected testis was found in boys aged 4 to 10 years (35.4% to 52.8%). The TAI values measured one year after orchiopexy were lower than preoperative ones. Significant difference in TAI values, ranging from 18.16% to 36.43% were observed in boys between 2 and 10 years (p < 0.001). In the youngest (0-2 yrs) and the oldest boys (> 10 yrs) the difference was not statistically significant. CONCLUSIONS The testicular atrophy index (TAI) proved to be a valuable and objective tool for qualifying patients with undescended testes for surgery as well as for monitoring the results of treatment. Its value of 20% and more should be considered an indication for surgery in boys with retractile testes.