Ultrasonographic diagnosis of inguinal hernia in children

During the past 2 years, 124 children with inguinal hernias diagnosed clinically and confirmed at operation were managed at our clinic. The processus vaginalis in the inguinal canal was examined preoperatively in all children by ultrasonography with a 10-MHz transducer (SSD-650CL, ASU-35WL-10, Aloka, Tokyo) as the intra-abdominal pressure increased and decreased. The ultrasonograms were divided into four types; type I, the intestine is observed in the inguinal canal; type II, the cystic pattern is seen at the internal ring of inguinal canal; type III, the patent processus vaginalis (PPV) enlarges when abdominal presure increases; and type IV, the PPV contains moving material without enlargement. Type I was observed in 17 children (11 males and 6 females), type II in 26 (6 males and 20 females), type III in 74 (60 males and 14 females), and type IV in 7 males; 71% of the male children showed type III and 50% of the females type II. All children with type IV had a communicating hydrocele. These results indicate that children showing one of the four ultrasonographic types have an inguinal hernia.