Cirurgia por orifícios naturais transcolônica: acesso NOTES peri-retal (PNA) para excisão mesoretal total

Transcolonic Perirectal NOTES Access (PNA): A feasibility study with survival in swine model

Transrectal access still has some unsolved issues such as spatial orientation, infection, access and site closure. This study presents a simple technique to perform transcolonic access with survival in a swine model series. A new technique for NOTES perirectal access to perform retroperitoneoscopy, peritoneoscopy, liver and lymphnode biopsies was performed in 6 pigs, using Totally NOTES technique. The specimens were extracted transanally. The flexible endoscope was inserted through a posterior transmural incision and the retrorectal space. Cultures of bacteria were documented for the retroperitoneal space and intra abdominal cavity after 14 days. Rectal site was closed using non-absorbable sutures. There was no bowel cleansing, nor preoperative fasting. The procedures were performed in 6 pigs through transcolonic natural orifice access using available endoscopic flexible instruments. All animals survived 14 days without complications, and cultures were negative. Histopathologic examination of the rectal closure site showed adequate healing of suture line and no micro abscesses. The results of feasibility and safety of experimental Transcolonic NOTES potentially brings new frontiers and future wider applications for minimally invasive surgery. The treatment of colorectal, abdominal and retroperitoneal diseases through a flexible Perirectal NOTES Access (PNA) is a promising new approach.

Perirectal NOTES access: "down-to-up" total mesorectal excision for rectal cancer

OBJECTIVES

Clinical natural orifice surgery has been applied for abdominal surgery in recent years, mostly by vaginal and oral access. The study describes preliminary successful human applications of transcolonic natural orifice transluminal endoscopic surgery (NOTES), using a new transrectal total mesorectal excision procedure for rectal cancer.

METHODS

Institutional review board approval was obtained for the study. In 2 patients with rectal adenocarcinoma, total mesorectal resection and rectosigmoidectomy with lymphadenectomy was performed using a low NOTES transcolonic access. "Down-to-up" mesorectal dissection was achieved either using a flexible scope or a transrectal single port device. The specimens were extracted transanally, and transorificial low anastomosis was performed.

RESULTS

Operative time was 350 and 360 minutes, respectively; no complications occurred and patients were discharged after 6 days.

CONCLUSION

Successful human reports on transcolonic NOTES suggest potential applications. The treatment of colorectal diseases through transorificial single port or flexible perirectal NOTES access are promising new approaches besides current methods to improve patient care.

A natural orifice transrectal approach for oncologic resection of the rectosigmoid: an experimental study and comparison with conventional laparoscopy

BACKGROUND

A transrectal (TR) approach for natural orifice translumenal endoscopic surgery (NOTES) makes sense for colorectal surgery because the colotomy can be incorporated into subsequent anastomosis. Because cancer is a primary indication for left-sided colon resection, oncologic standards will have to be met by a NOTES procedure. This study aimed to assess whether pure TR rectosigmoidectomy can be performed with strict adherence to oncologic principles compared with a conventional laparoscopically assisted approach (LAP).

METHODS

Human male cadavers were allocated to either TR (n = 4) or LAP (n = 2). A simulated sigmoid lesion was created at 25 cm. Transrectal retrograde mobilization of the rectosigmoid was performed using conventional transanal endoscopic microsurgery (TEM) instrumentation. After ligation of the superior hemorrhoidal artery and further mobilization, the specimen was delivered transanally and divided extracorporeally. Using a circular stapler, NOTES colorectal anastomosis was performed. Lymph node yield, adequate resection margins, and operative time were compared with LAP.

RESULTS

Transrectal retrograde rectosigmoid dissection was achieved in all attempts (4/4) and showed numbers of lymph nodes (median, 5; range, 3-6) similar to the LAP group (median, 4.5; range, 2-7). One pure TR approach failed to resect the lesion. Three TR procedures required additional mobilization via an abdominal approach to provide adequate margins. The mean length of TR specimens was 16 ± 4 cm compared with 31 ± 9 cm achieved by LAP (p < 0.01). The TR operative time was significantly longer (247 ± 15 vs 110 ± 14 min).

CONCLUSION

Lymph node yield during TR rectosigmoidectomy was similar to that achieved by the LAP approach. However, conventional TEM instrumentation alone did not permit adequate colon mobilization. This indicates a need for flexible instrumentation or other technical solutions to perform true NOTES colectomies.