Importance of the Duodenal Window and Fredet's Fascia in Laparoscopic Right Hemicolectomy. Technical Note

Background: Laparoscopic right hemicolectomy requires a precise anatomical dissection to mobilise the right and proximal transverse mesocolon, following the avascular fusion planes of Toldt and Fredet. Fredet's plane is crucial to the preparation of the origin of vessels. Easy access to Fredet's and Toldt's fasciae can be obtained through the "duodenal window", a flimsy area of the root of the proximal transverse mesocolon, the margins of which are the right border of the superior mesenteric pedicle, the ileocolic pedicle, the right colic pedicle and the marginal artery. Method: We propose that dissection of the duodenal window should be the first step in laparoscopic right hemicolectomy, to obtain easy access to the duodenopancreatic plane and prepare the fascia. Results: This "duodenal window-first" technique has been applied in 45 laparoscopic right hemicolectomies and 14 laparoscopic extended right hemicolectomies, with only two conversions to open surgery. The duodenal window was easily identified in all but 3 cases with significant visceral obesity. No significant intra- or postoperative morbidity was recorded in these cases and the median postoperative length of stay was 4 days. All resections were R0 and an adequate number of retrieved lymph nodes were obtained in almost all cases. Conclusion: The duodenal window-first approach is a feasible and safe technique to standardise the first steps of radical laparoscopic right hemicolectomy, allowing prompt and complete anatomical identification and dissection