Ultrasonic exploration of contralateral side in pediatric patients with inguinal hernia.

The width of low echoic region at the internal ring (WLIR) of an inguinal canal demonstrated by ultrasonography was applied in the preoperative diagnosis of the contralateral side in pediatric patients with inguinal hernia. The ultrasonic diagnosis of 39 pediatric patients with inguinal hernia and 38 children without inguinal hernia under 15 years of age were conducted at Hamamatsu University Hospital from April 1988 to January 1989. The WLIR of children without inguinal hernia were within 6 mm in boys under 15 years of age and within 3 mm in girls under 5 years of age. There were no statistically significant differences between the WLIR of the right side and that of the left side, and the WLIR of the following three age groups also demonstrated no statistical significance: under 1 year of age, 1 to 5 years of age, 5 to 15 years of age. On the other hand, the WLIR of the hernia side of pediatric patients with inguinal hernia were significantly wider than that of the contralateral side in boys and girls under 5 years of age (P less than 0.01), as well as in boys 5 to 15 years of age (P less than 0.05). Therefore, we recommend a contralateral exploration for pediatric patients with inguinal hernia when the WLIR is 7 mm or more in boys under 15 years of age and 4 mm or more in girls under 5 years of age.