LAUSR

Acquired “interstitial” hernias are extremely rare and can be a serious complication after ventral hernia repair with placement of an onlay mesh. We describe two cases of interstitial hernias after onlay repair. Case 1: male patient of 59-year-old was submitted to a segmental enterectomy due to intestinal perforation and developed a hernia that was then surgical repaired with closure and an onlay mesh . Case 2: 58-year-old male with medical history of polimyelitis with two previous umbilical hernia repair interventions, being the last one with an onlay mesh. Both patients at the physical examination revealed a symptomatic bulge difficult to characterize and the CT scan showed multiples defects with the hernia sac between the anterior aponeurosis and the onlay mesh. In both cases, the previous mesh was surgically removed, and repair of the abdominal wall was achieved with the placement of a macroporous retromuscular polypropylene mesh with 48mg/m2 density and complete medialization of the rectus muscles. The diagnosis of interstitial hernias may be challenging, and CT imaging is mandatory for confirmation. Due to the high risk of complications such as strangulation, these hernias should always be corrected in a timely manner.