Contralateral Occult Inguinal Hernia Unmasked During Final Low-Pressure Inspection in a Transabdominal Preperitoneal (TAPP) Procedure: A Case Report

Transabdominal preperitoneal (TAPP) repair allows assessment of both groins, yet small contralateral defects may be pressure-dependent and inapparent at the initial survey. We report a case of an 87-year-old patient with a reducible left groin bulge. At the start of TAPP, intraperitoneal inspection showed a left direct inguinal hernia, classified as M3 according to the European Hernia Society (EHS) classification, and no obvious right-sided defect. After left-sided preperitoneal dissection, mesh placement, and peritoneal closure, the pneumoperitoneum - initially maintained at 10 mmHg - was reduced to 7 mmHg for a final bilateral inspection before trocar removal. At that point, a subtle bulge at the right internal ring, corresponding to an indirect inguinal hernia (L1 in the EHS classification), became evident and was repaired in the same session with preperitoneal mesh and peritoneal closure. The operative time was 93 minutes, blood loss was negligible, and recovery was uneventful. This case highlights that inspection should not only be performed at the beginning of TAPP but also at the end before closure. A brief low-pressure final check can unmask contralateral occult inguinal hernias that are not visible at the initial high-pressure survey, which might allow for definitive single-session management.