Evaluation of Current Devices in Single-Incision Laparoscopic Colorectal Surgery: A Preliminary Experience in 32 Consecutive Cases: Reply

We thank Vestweber et al. [1] for their interest in our article [2]. We embarked on single-incision laparoscopic surgery (SILS) anterior resections (AR) with great interest as did many surgeons around the world and the article was a report of our initial results and learning curve. Essentially, the single-port devices all have three built-in ports: one for the camera, one for the energy device for cutting/ coagulation, and one for retracting. From our initial experience, the technical difficulties can be summarized as follows: First, we encountered several difficulties during mobilization with just one retracting port. This occurred with large bulky tumors due to the weight of the entire specimen. Furthermore, we had several cases where there were interbowel loop adhesions that made adhesiolysis technically challenging due to poor separation of bowel loops, with only one device performing retraction and the subsequent risk of thermal injury to adjacent bowel loops. In addition, the presence of a long loopy sigmoid colon made the visualization of windows for cutting or stapling hazardous due to the floppiness of the proximal or distal portion of the bowel obscuring the view. We have subsequently noted different methods to overcome these problems. These include use of a nylon tape sling, which is created through a window on the mesenteric border of the colon and lifted through the abdominal wall, and hence does not use a port per se. We have also noted the ingenious use of an abdominal wall magnet aided by a bar to provide suspension. Interestingly, the single port was also placed through the right flank of the patient [3]. Second, the other difficulty that we encountered was in the firing of the endoscopic stapler across the distal rectal stump, especially after a TME. In conventional laparoscopic techniques, one way to fire the stapler includes inserting it through the flank ports and firing it in a right-toleft fashion. Other authors insert a Pfannenstiel port and fire the stapler vertically downward. We initially approached the rectum laterally with the stapler but it was difficult to see the inferior jaw of the stapler and there were limitations in achieving good margins due to the restricted articulation of the stapler. Thus, an extra port was subsequently inserted. However, we have found that this limitation may be overcome if the stapler is fired in a top-down fashion but may not be suitable for bulky lesions. One other method would be to insert the single port in the flank rather than in the umbilicus, thus improving the ability to reach the pelvic floor in a more ergonomic fashion. Our results highlight the need for modification to our SILS AR technique, which is slightly different than our conventional laparoscopic AR technique. We agree that the SILS is not extraordinarily difficult but it certainly is a technique that needs to continue to evolve before it can be easily performed by all surgeons worldwide. Essentially, the extra port inserted is unlikely to produce a poorer outcome in the patient, and it certainly improves the safety and technical success for the surgeon. We are hesitant to extend the use of SILS for all indications of surgery as we feel there are still technical limitations. We congratulate the Vestweber [4] group on reporting their outcome on their large number of single-port patients and look forward to learning about their technical developments. We also await further data from our colleagues worldwide. M. H. Chew (&) M. T.-C. Wong Y.-K. Lim K.-H. Ng K.-W. Eu C.-L. Tang Department of Colorectal Surgery, Singapore General Hospital, 1 Hospital Drive, Singapore 169608, Singapore e-mail: ustwo@singnet.com.sg