Inguinal hernia in children: US versus exploratory surgery and intraoperative contralateral laparoscopy

PURPOSE: To analyze the value of ultrasound (US) in the preoperative recognition of clinically apparent and inapparent inguinal hernias (or patent processus vaginalis). MATERIALS AND METHODS: Two hundred sixty children (197 boys, 63 girls), in whom a clinical diagnosis of inguinal hernia (226 unilateral hernias, 34 bilateral hernias) had been made, underwent US examination with a 7.0-MHz linear-array transducer. The contralateral internal inguinal ring was evaluated by means of intraoperative laparoscopy in 141 patients. The 197 boys were grouped together by age (<12 months, 12-24 months, 24-48 months, 48-72 months, and >72 months). RESULTS: In the 260 patients who underwent inguinal herniorrhaphy, 246 hernias (95%) were correctly diagnosed at US based on criteria of an internal inguinal ring width greater than 4 mm in diameter or the presence of fluid or organs in the inguinal canal at rest or during straining. A total of 473 hernias were confirmed surgically and 459 (97%) hernias were correctly detected at US. A statistically significant difference in the mean width of the internal inguinal ring of the five age groups was found between patients at rest and during straining (P <.05) in US measurement of the 197 surgically proved cases in boys. CONCLUSION: US is a noninvasive, readily available, and highly accurate (95%) method for evaluating the presence of inguinal hernia in children at risk, especially when the clinical findings are equivocal or normal. US can provide an objective measure in determining the advisability of exploratory inguinal surgery in such cases.