NOTES: a review of the technical problems encountered and their solutions.

BACKGROUND Natural orifice translumenal endoscopic surgery (NOTES) is currently investigated and developed worldwide. In the past few years, multiple groups have confronted this challenge. Many technical problems are encountered in this technique due to the currently available tools for this approach. Some of the unique technical problems in NOTES include: blindly performed primary incisions; uncontrolled pneumoperitoneal pressure; no support for the endoscope in the abdominal cavity; inadequate vision; insufficient illumination; limited retraction and exposure; and the complexity of suturing and performing a safe anastomosis. In this paper, we review the problems encountered in NOTES and provide possible temporary solutions. METHODS Acute and survival studies were performed on 15 farm pigs. The hybrid technique approach (i.e., endoscopic surgery with the aid of laparoscopic vision) was performed in all cases. Procedures performed included liver biopsies, bilateral tubal ligation, oophprectomy, cholecystectomy, splenectomy and small bowel resection, and anastomosis. RESULTS All attempted procedures were successfully performed. New methods and techniques were developed to overcome the technical problems. Closure of the gastrotomy was achieved by T-bar sutures and by stapler closure of the stomach incision. Small bowel anastomosis was achieved by the dual-lumen NOTES technique. CONCLUSIONS The hybrid technique serves as a temporary approach to aid in developing the NOTES technique. A rectal or vaginal port of entry enables and facilitates gastrointestinal NOTES by using available laparoscopic instruments. The common operations performed today in the laparoscopic fashion could be probably performed in the NOTES approach. The safety of these procedures, however, is yet to be determined.