Known in Egyptian times, when it was regarded as an instrument of divination, the great epiploon, as named by Aristotle, is a fold in the rear mesogastric area located behind the abdominal wall and in front of the intestinal loops. The use of the great epiploon in urology dates back to 1935, when it was used in the treatment of vesicovaginal fistulae . In the 1970s, Turner-Warwick  reported on the benefits of placing an omentum flap in contact with bulbar urethroplasties to reduce urinary fistulae, urethral strictures and infections. The great epiploon is often used as an interposing tissue in the treatment of vesicovaginal, rectourethral (in particular after radical prostatectomy) and rectovaginal fistulae . In the event of any extensive loss of substance, the great epiploon can be used because of its secondary epithelialization ability. Finally, the great epiploon can be used in other situations: peri-ureteric omentoplasty after extensive ureterolysis for retroperitoneal fibrosis , omentoplasty to fill the residual cavity left by a large renal hydatid cyst  or even refractory lymphoceles after renal transplantation.
Making a flap of the large epiploon or carrying out an omentoplasty is a simple and reproducible technique provided that there is proper awareness of the vascularization of the great epiploon. The main complication that can arise is necrosis of the flap, happily a rare occurrence, estimated at ≈ 3%. We describe our technique, together with some advice intended to help in the practice and chances of success of omentoplasty.
VASCULARIZATION OF THE GREAT EPIPLOON
The great epiploon is vascularized by the two gastroepiploic arteries [7,8]. The diameter of the right gastroepiploic artery in humans is 1.5–3 mm; the left gastroepiploic artery has a slightly smaller diameter of 1.2–2.9 mm.
The right gastroepiploic artery starts from the bifurcation of the gastroduodenal artery, and descends along the pylorus, into which several branches lead, only the first of them irrigating the juxta-pyloric area of the stomach (which means that care needs to be taken with them during omentoplasty), and gives rise to five to eight epiploic arteries including the voluminous right epiploic artery; the right gastroepiploic artery ends in an anastomosis with the left gastroepiploic artery to the medium third of the greater curvature of the stomach, where it forms the arterial circle of the greater curvature.
The left gastroepiploic artery arises from the trunk of the splenic artery or one of its lower hilar division branches. It descends along the greater gastric curvature within the gastrocolic ligament and leaves the short vessels before anastomosing with the right gastroepiploic artery. The calibre of the arterial circle of the greater curvature is bigger on the right side, which explains why most of the flaps are pedicled on the right gastroepiploic artery. The venous return, parallel to the arterial system, drains into the gastrocolic venous trunk on the right and into the splenic vein on the left.
SURGICAL ANATOMY AND TECHNIQUES FOR MOBILIZING THE GREAT EPIPLOON
We inject a buflomedil-type vasodilator (i.v. 400 mg) 30 min before any intervention on the flap. This vasodilator administration is then continued at the same dose for 3 days by a daily injection. The initial phase of the omentoplasty is based on a colo-epiploic detachment and this alone, in 10% of cases, enables the great epiploon to be mobilized up to the inguinal ligament. Otherwise, the gastrocolic ligament needs to be opened between the greater gastric curvature and the gastroepiploic arcade, which should be treated with care. The short vessels to the gastric area are then carefully detached, avoiding any vascular lesion of the arcade up to 5 cm from the origin of the gastroepiploic on the right, and 3 cm from the anastomotic plexus on the left. Thus, one should not go too far back to the origin of the gastroepiploic arteries to preserve a satisfactory venous return to the flap. If this rule is not observed, there is a risk of infarction of the flap by venous stasis ischaemia.
Where a flap is too short, it can be lengthened by splitting it into two by a second longitudinal incision perpendicular to the gastroepiploic arcade. This type of plasty, preferentially made on the right flaps (as they are generally better vascularized), should only be made if absolutely necessary as there is a risk of the flap vascularization becoming fragile. Once the omentoplasty is in place, we use a bath of hot physiological solution for 10 min. Making an omentoplasty can be difficult or even impossible in the event of a surgical history involving the stomach or the transverse colon.