Significance of routine preoperative prone computed tomography for predicting intractable cases of inguinal hernias treated by transabdominal preperitoneal repair

Physical examination is the standard diagnostic approach for adult inguinal hernias. We aimed to evaluate the clinical utility of routine preoperative computed tomography scans in the prone position for predicting intractable cases of inguinal hernias before performing transabdominal preperitoneal repairs. We retrospectively analyzed 56 lesions in 48 patients with inguinal hernias who underwent prone computed tomography scans prior to transabdominal preperitoneal repairs. To assess the ability of prone computed tomography to enable the accurate preoperative diagnosis of inguinal hernias, we compared preoperative hernia types as classified through hernia computed tomography and intraoperative diagnosis. We also analyzed the relationship between operation time and hernia type in unilateral cases (n = 40). The overall hernia computed tomography detection and classification accuracy rates were 81.0% and 83.9%, respectively, using the Japan Hernia Society classification system (2009 version) and 84.3% and 91.2%, respectively, using the European Hernia Society classification system. There were no differences in the hernia type frequencies between the shorter (n = 20) and longer (n = 20) operation time groups. Two patients had sliding inguinal hernias with prolapsing bladders, both of which were detectable using preoperative prone computed tomography. Although transabdominal preperitoneal repairs were completed in both cases, the operation times were exceptionally long (185 and 291 minute). Preoperative prone computed tomography is useful for predicting intractable cases of inguinal hernias. Prone computed tomography can play a significant role in not only typing and differentiating hernias from other diseases, but also in helping surgeons appropriately treat unexpected intractable cases with laparoscopic surgery.