Preoperative ultrasonographic evaluation of the contralateral patent processus vaginalis at the level of the internal inguinal ring is useful for predicting contralateral inguinal hernias in children: a prospective analysis
1. Department of Pediatric Surgery, Nihon University School of Medicine, 30-1, Ohyaguchi-Kamicho, Itabashi-Ku, Tokyo, 173-8610, Japan 2. Department of Pediatric Surgery, Tokyo Metropolitan Ohtsuka Hospital, Toshima, Tokyo, Japan