P-100 ANATOMICAL STUDY ON THE PREPERITONEAL FAT DISTRIBUTION IN EXTENDED RETROMUSCULAR PREPERITONEAL DISSECTION: FROM THE FATTY TRIANGLE TO THE FATTY TRIDENT

Aim

Extended retromuscular dissection performed for abdominal wall reconstruction in complex abdominal wall repair 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.

Material and methods

Thirty frozen cadaver torsos were dissected by posterior component separation. The shape of the preperitoneal fat was identified, and the dimensions and more significant distances were calculated.

Results

The results showed that the preperitoneal fat resembles a trident, exists along the midline under the linea alba, and expands in the epigastric area into a rhomboid shape. The fatty triangle was found to be a part of this rhomboid. The mean rhomboid area was 35 cm2. Caudally, the midline preperitoneal fat widened under the arcuate line to reach the Retzius space. Laterally, the Bogros space communicated the root of the trident with the paracolic gutters, Toldt's fascia, and pararenal fats, forming the lateral prong of the trident. The mean width of the midline prong at the umbilicus was 2.8 cm. It was easier to tear the peritoneum outside the area reinforced by the fatty trident.

Conclusions

The concept of preperitoneal fatty trident may be of practical assistance to perform various hernia procedures, from the simple ventral hernia repair to the more complex preperitoneal ventral repair or posterior component separation techniques. The consistency of this layer allows us to follow our plane between the peritoneum and muscle layers to extend the preperitoneal dissection.

V-018 PREOPERATIVE OPTIMIZATION AND POSTERIOR COMPONENT SEPARATION WITH INTRAOPERATIVE MONITORING OF RECTUS MUSCLE INERVATION FOR LOSS OF DOMAIN INCISIONAL HERNIA

Aim

The importance of an appropriate patient optimization (botulin toxin and pneumoperitoneum) and adequate surgical technique is highlighted.The possibility of intraoperative monitoring of the nerves that may be injured during posterior component separation is explained

Material and methods

We present a 74 years old man, past smoker, with history of hypertension, steatohepatitis and chronic bronchopathy

Results

This is a disastrous but unfortunately not so uncommon story of a failed repair of a simple umbilical hernia with 3 previous unsuccessful attempts of repair with and without mesh. After the last surgery the patient developed a giant incisional hernia with loss of domain. Optimization consisted of improving nutritional status, respiratory physiotherapy, botulin toxin and pneumoperitoneum. The surgery was made using previous skin scar. After dissecting the retrorectus space, a posterior component separation was made with the aid of monitoring the nerves that come to innervate the rectus abdominis. An overextended overlapped was obtained. A patch of absorbable mesh was used to completely close the peritoneum. A combination of absorbable and permanent synthetic mesh was used as giant reinforcement of the visceral sac. The only points of fixation were the Cooper Ligaments. The patient had a satisfactory recovery without complications and was discharged on the 8th postoperative day.

Conclusions

Loss of domain incisional hernias is a real surgical challenge. The combination of a good preoperative strategy (preoperative neumoperitoneum) and surgical technique (TAR and pannniculectomy) gives a great opportunity to solve very complex cases of incisional hernia.

Pathways of the preperitoneal plane: from the “fatty triangle” in Rives to the “fatty trident" in extended retromuscular abdominal wall reconstruction. A tribute to Prof. Schumpelick

PURPOSE

Extended retromuscular dissection performed for abdominal wall reconstruction in complex abdominal wall repair 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 in retromuscular preperitoneal dissections.

METHODS

Thirty frozen cadaver torsos were dissected by posterior component separation. The shape of the preperitoneal fat was identified, and the dimensions and more significant distances were calculated.

RESULTS

The results showed that the preperitoneal fat resembles a trident, exists along the midline under the linea alba, and expands in the epigastric area 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 the Retzius space. Laterally, the Bogros space communicated the root of the trident with the paracolic gutters, Toldt's fascia, and pararenal fats, forming the lateral prong of the trident. The peritoneum not covered by the preperitoneal fatty 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 to perform various hernia procedures, from the simple ventral hernia repair to the more complex preperitoneal ventral repair or posterior component separation techniques. The consistency of this layer allows us to follow three specific pathways to find our plane between the peritoneum and muscle layers to extend the preperitoneal dissection.