OC-073 PATHWAYS OF THE PREPERITONEAL PLANE: FROM THE “FATTY TRIANGLE” IN RIVES TO THE “FATTY TRIDENT” IN EXTENDED RETROMUSCULAR ABDOMINAL WALL RECONSTRUCTION

Abstract

Abstract Aim Retromuscular dissection performed for abdominal wall reconstruction in complex abdominal wall has progressively exposed the anatomy between the peritoneal layer and abdominal wall muscles. This study aimed to assess the morphology and distribution of preperitoneal fat in a cadaveric model and its influence on retromuscular preperitoneal dissections. Material & Methods Thirty frozen cadaver torsos were dissected by posterior component separation (PCS). The shape of the preperitoneal fat was identified, and the dimensions and distances were calculated. Results Results showed that preperitoneal fat resembles a trident, along the midline under the linea alba, and expands in the epigastrium into a rhomboid shape. The fatty triangle was found to be a part of this rhomboid. Caudally, the midline preperitoneal fat widened under the arcuate line to reach Retzius´s space. Bogros space communicated the root of the trident laterally with the paracolic gutters, Toldt's fascia, and pararenal fats, forming the lateral prong of the trident. The peritoneum uncovered by the preperitoneal trident was easy to break. Three pathways could be tracked following the distribution of this fat that facilitated the dissection of the preperitoneal space to prepare the landing zone of the meshes in hernia repair. Conclusion The concept of preperitoneal fatty trident may be of practical assistance in performing hernia procedures, from the simple ventral hernia repair to more complex preperitoneal ventral repair or PCS techniques. The consistency of this layer allows us to follow three specific pathways to the plane between the peritoneum and muscles to extend the preperitoneal dissection.