Since 1995, we have performed “neoanus surgery”.

Introduction of
‘neoanus with a pudendal nerve anastomosis’ (NAPNA)
after abdominoperineal excision of the rectum 
　　　　　　　　　　　　　　　　　　　　(Institure of the Stomaless on the Web)

Chapter 3.

Outlines of the operation avoiding colostomy

There are two methods in the neo-anus surgery: the technique concurrently done with the operation to resect rectal cancer and the one for those who have a stoma (ostomates). In this chapter, the operation done concurrently with the resection of the rectum will be described.

First, the operation to resect rectal cancer is done as previously established. After rectal cancer is resected, a colon pouch is prepared with part of the remaining large intestine, to let it function as a reservoir like the rectum (retention of feces). Then, a few procedures are added to supplement a lack of the internal sphincter. The end of the colon is sutured into the original place for the anus to prepare for the future neo-anus.

Sphincter may be prepared on the same day, but usually the patient is discharged for safety reasons and sphincter will be reconstructed in the second-step operation after the patient is readmitted to the hospital three to six weeks later. Part of the gluteus maximum muscle is used to create new sphincter governed by the pudendal nerve that replaces the original nerve for the gluteus maximum muscle (the inferior gluteal nerve). This sphincter can function naturally as new-anus by the governance of the pudendal nerve.

Operational procedure

The outline of the operation is as follows.  (The figure below is taken directly from my papers. The method described herein is a classical neo-anus surgery and a little different from the modified procedure that we currently perform. Currently, refinement is added, including preparation of the internal sphincter. )

Rectal cancer is completely resected in order to seek full elimination whether or not the neo-anus is reconstructed. When the resection is finished, reconstruction of the neo-anus begins.

As shown in Figure 1, the colon is made fully loose so that the end of the colon can be drawn to the site of the original anus without tension.  To reconstruct the reservoir function of the rectum (retention of feces), a small colonic pouch is prepared.

Part of the gluteus maximus, or the muscle of the cheek of the buttocks, is used to create the new sphincter as shown in Figures 2 and 3.  As in Figure 2, the blood supply (arteries) feeders can separate the gluteus muscle: the upper part is supplied by the superior gluteal artery and the lower part is supplied by the inferior gluteal artery. (When the gluteus muscle is damaged as a whole, gait will be impaired. In this operation, the upper part is left untouched while the lower part is used, and no gait disturbance will appear.)

From figure 2, the buttocks are in the prone position. 

The gluteus maximus is controlled as a whole by the inferior gluteal nerve (Figure 3).

 Then, when new sphincter is prepared with the lower part of the gluteus maximus, it is necessary to leave the upper branch of the inferior gluteal nerve intact to keep the function of the upper part.


Figure 5 demonstrates the process of suturing the cut-end of the peripheral side of the inferior gluteal muscle and the cut-end of the central side of the pudendal nerve. This nerve is sutured under microscopy.

Around the openings of the colon pouch drawn to the perineum for excretion, new sphincter is created with the lower part of the gluteus maximus the pudendal nerve is sutured into. (In fact, there are several methods or tricks in this process.)

Figure 7 demonstrates a side-view image of the operation.

The bottom of the pelvic cavity is created with both the colon pouch as the reservoir of the rectum (for feces retention) and the new sphincter that the pudendal nerve, assuming the function of the anal sphincter, is sutured into.

Index .
Preface. to avoid colostomy (stoma), there is a neoanus surgery.
Chapter 1. Comments on rectal cancer for neoanus surgery
Chapter 2. A path to develop a new operation to avoid colostomy (neoanus surgery)
Chapter 3. Outlines of the operation avoiding colostomy
Chapter 4 Life without a stoma
Chapter 5. Miscellaneous with self-introduction
Chapter 6 Bibliography
Link


Correspondence to:
Tomoyuki Sato M.D., Ph.D.
Assistant Professor, Center for Clinical Medicine and Reserch, International University of Health and Welfare
Iguchi, Nishinasuno-machi, Nasu-gun, Tochigi-ken, Japan
Email address: tomosato@iuhw.ac.jp
Fax: to Dr. Sato +81-287-39-3001

or
Tomoyuki Sato M.D., Ph.D. Department of Surgery, Jichi Medical School
3311-1 Yakushiji, Minamikawachi-machi, Kawachi-gun, Tochigi-ken, 329-0498, Japan
Email address: tomoyuki@jichi,ac.jp
fax: +81-285-44-3234

Link to the Japanese website of the stomaless surgery (Neo-anus)