Predictive Value of the Contralateral Testicular Hypertrophy for Testicular Nubbin in Patients with Unilateral Impalpable Testis

Won, Ho Suk; Park, Kwan Hyun; Lee, Sung Won; Chai, Soo Eung

Abstract

PURPOSE: Many pediatric urologists perform diagnostic laparoscopy for the evaluation of the patients with impalpable testis. While laparoscopic procedure is very useful for accurate localization of the impalpable testis, it has potentially significant complications especially in the less experienced hands. Previous studies demonstrated that the contralateral testicular hypertrophy (CTH) could be induced by hemicastration in prepubertal animals. The CTH can occur in the cases of the testicular nubbin (TN), which is usually removed by inguinal approach. If we can perfectly predict the TN by confirming the CTH, the diagnostic laparoscopic procedure could be omitted in case of unilateral impalpable testis with the CTH. Therefore, we studied to determine the correlation between CTH and TN in children with unilateral impalpable testis.
MATERIALS AND METHODS
From May 1995 to May 1998, 22 boys (1-13y) with unilateral impalpable testis were evaluated at our institution. Preoperative ultrasonography was performed to measure the size of the descended palpable testis. The CTH was defined if the longitudinal diameter of the descended testis was greater than the mean +2 S.D. of the normal testicular size in Korean children.
RESULTS
In cases with the CTH, the sensitivity and specificity for prediction of the TN were 82% and 91%, respectively. The positive and negative predictive values for TN using the CTH were 90% and 83%, respectively.
CONCLUSIONS
The correlation between CTH and TN in unilateral impalpable testis was significantly high (p=0.015), but there were a few exceptional cases. Therefore, we could not replace the diagnostic laparoscopic procedure using the CTH in the evaluation of the children with unilateral impalpable testis.