Stapled trans-anal rectal resection (STARR) is a minimally invasive surgical procedure for conditions such as obstructed defecation syndrome, internal rectal prolapse, and rectocele. Circular surgical staplers are used to resect (remove) sections of the wall of the rectum via the anus. The defects are then closed with surgical staples. A modification of the technique is Contour Transtar. The average age of patients undergoing STARR is about 55 years, and 83% of procedures are carried out on females.
The procedure is controversial. The results of many thousands of STARR procedures have been published in research. Proponents state that the procedure is simple, minimally invasive, safe, and effective. Skeptics argue that the complications may be significant (fecal urgency, urge fecal incontinence) or rarely even life-threatening. There is a general trend away from STARR towards ventral rectopexy for surgical treatment of obstructed defecation syndrome.
Indications Surgery may be indicated if there is no response to non-surgical treatments such as diet, laxatives, enemas, and pelvic floor physical therapy for more than 6 months. The main indications for STARR are internal rectal prolapse (internal intussusception) or rectocele in people with obstructed defecation syndrome. Obstructed defecation syndrome has no fixed definition, but encompasses symptoms such as straining during more than 25% of defecation attempts, digitation, sense of incomplete evacuation, laxative abuse, and dependence on enemas more than once per week. In rectocele, female patients might use digital pressure on the anterior perinueum or on the back wall of the lower vagina. This reduces the rectocele pouch and straightens the anorectum, facilitating defecation. In internal rectal prolapse, patients usually apply digital pressure inside the rectum. This involves inserting a finger into the rectum to assist with evacuation. This enables manual reduction of the intussuscepted or prolapsed rectal tissue and facilitates stool passage. Other potential symptoms of obstructed defecation which may be indications for STARR include frequent need to defecate again after evacuation, extended time spent in the toilet, pelvic pressure, rectal discomfort, and perineal pain.
Internal rectal prolapse and rectocele often occur together, but not always. In rectocele, the rectal wall balloons out. In internal rectal prolapse, the rectal wall prolapses into the lumen of the rectum. The STARR is therefore able to treat these conditions by removing the redundant area of rectal wall and restoring normal anatomy.
STARR has also been used to treat rectal mucosal prolapse, hemorrhoids (when associated with rectal internal mucosal prolapse), and solitary rectal ulcer syndrome (which often occurs with internal rectal prolapse). STARR has also been used for descending perineum syndrome.
Up to 50% of people have some detectable degree of internal rectal prolapse when defecography is conducted on healthy volunteers with no symptoms. Rectoceles are detected in 80% of healthy female volunteers on defecography. Some consider defects like internal rectal prolapse and rectocele as consequences of obstructed defecation syndrome, rather than causes. Chronic straining / dyssynergic defecation may be the original and underlying pathology in obstructed defecation. Even if anatomic defects can be detected, they may not be the cause of symptoms. Therefore, simply detecting internal rectal prolapse or rectocele may not be a valid indication for surgery. Surgery may be considered if there is a combination of anatomic abnormalities with the characteristic symptoms of obstructed defecation, and after non surgical treatment has failed.
Several optional investigations have been suggested in the assessment of patients for STARR, including clinical evaluation of sphincter function, proctoscopy / sigmoidoscopy, colonoscopy (or barium enema), defecography, small bowel series, colonic transit study, anal manometry (including assessment of rectal compliance and rectal capacity), electromyography, cystourethrogram, and assessment from a gynecologist or urologist.
Contra-indications Dyssynergic defecation (anismus). Enterocele, especially if detectable at rest. Fecal incontinence. Symptoms resulting from other problems such as slow transit constipation or irritable bowel syndrome. External rectal prolapse (complete / full thickness rectal prolapse). Infection in perineal region (e.g. anorectal abscess, anal fistula). Recto-vaginal fistula. Inflammatory bowel disease. Radiation proctitis. Anal stricture (which prevents insertion of stapler). Significant gynecological or urinary pathology which requires combined treatment. Surgical mesh or other foreign material adjacent to rectum. No detectable abnormality. Significant fibrosis in region of rectum. Prior surgical anastomosis in rectum. Psychiatric disorder.
STARR is performed without direct vision. Therefore, any structure in the region of the recto-uterine pouch (pouch of Douglas) in females or the rectovesical pouch in males is at risk during the procedure. For example, an enterocele, which is a protrusion of peritoneum containing small intestine between the vagina and the rectum. Enteroceles are fairly common in people with pelvic floor disorders. Some have recommended to use laparoscopy while carrying out STARR for patients with an enterocele. MRI or defecography should demonstrate an enterocele.
Technique Before the procedure an enema is usually prescribed. The procedure may be performed under general anesthesia or spinal anesthesia. Antibiotics (usually metronidazole with a cephalosporin or ciprofloxacin) are given after the onset of anesthesia. This combination acts on both aerobic bacteria and anaerobic bacteria. The patient is usually placed in the lithotomy position.
The trans-anal approach is used (i.e., via the anus). Sometimes this is termed the perineal approach. STARR has been categorized as "natural orifice surgery" because it is performed via an existing body orifice and therefore leaves no externally visible scars.
2 circular staplers are used sequentially. First, one stapler is used anteriorly (at the front) to remove rectal wall on the anterior surface of the lower rectum. Then the other stapler is used posteriorly (at the back) to remove a second section of posterior rectal wall. The anterior resection addresses the bulging rectocele and the anterior and posterior resections together aim to correct the intussusception / internal rectal prolapse. The full thickness of the rectal wall is removed, including all three layers (mucosa, submucosa, and rectal muscle wall). The defects that are left after removal of sections of rectal wall are anastomosed (joined together) using staples. The procedure usually lasts about 45 minutes. The end result is a circumferential row of staples reconnecting the edges of the rectal wall. It is important that the surgeon does not incorporate the vaginal wall during stapling. Another potential error is placing staples too close to the dentate line in the anal canal.
The most commonly used stapler is the "Proximate" PPH-01 stapler (Ethicon Endo-Surgery Inc.). The PPH-01 stapler was designed for use with prolapsed hemorrhoids, in the procedure for prolapse and hemorrhoids technique (PPH).
A newer stapler (PPH03) was developed, but it is less commonly used. This stapler had a slightly reduced closed staple height, intended to reduce risk of bleeding during stapled hemorrhoidopexy and STARR. This stapler is no longer licensed for STARR because the staple line height was deemed insufficient.
The aim of the procedure is to restore a normal anatomic relationship between the rectum and the anal canal while preserving the anal sphincters and the hemorrhoidal cushions. This is done by removal of the redundant area of rectal wall, improving venous perfusion, and pulling up of the anal mucosa and perianal tissues, thereby reducing the friction and impact of stool on the surface of the tissues and reducing symptoms of obstructed defecation syndrome.
The limitations of the STARR procedure are that it is performed "blind" (without direct vision) and that the maximum area of tissue able to be resected was dictated by the capacity of the stapling device. Therefore, the STARR procedure does not able increasing the size of resection of rectal wall for larger defects. STARR is able to reliably resect internal rectal prolapse of up to 8 cm and rectoceles less than 5 cm. Sometimes there will be signs of residual internal rectal prolapse or rectocele after the procedure.
Contour Transtar The TRANSTAR procedure uses a curved cutter stapler with a reloadable cartridge which has been designed specifically for this application. They include CCS-30 Contour Transtar (Ethicon Endo-Surgery Inc.), STR10 Transtar (Ethicon Endo-Surgery Inc.) and TM-STR5G Contour Transtar (Ethicon Endo-Surgery Inc.). Newer, high volume staplers (CPH34HV, CPH36, or TST36) enable resection of larger areas, thereby allowing larger prolapses to be treated with the procedure. High volume staplers also enable the use of a single stapler instead of two. Contour Transtar therefore allows the surgeon to customize the extent of the rectal wall resection to the individual prolapse. This may enable more reliable relief of symptoms for patients with larger intussusceptions. It is also possible to perform Contour Transtar under direct vision. Another claimed advantage of Contour Transtar is that it avoids the lateral "dog-ears" created when using the PPH-01 stapler.
Recovery STARR is less invasive than laparoscopic procedures. It may be performed on a day-case / outpatient surgery basis. Most patients spend between one or two days in hospital. Normal diet is resumed as soon as the patient wishes. Bulk forming agents and stool softeners may be given so as to remove the need for straining during defecation after the procedure. Analgesia (pain killers) after the procedure should not be opioid so as to avoid the constipating side effect.
Complications
Early (peri-operative) complications of STARR and Contour Transtar Bleeding (which may be early or delayed, leading to formation of a stable pelvic/perirectal hematoma). Bleeding is usually minor and transfusion is not required. Placement of a manual suture to reinforce the staple line has been recommended to risk of bleeding. A second procedure may be needed if there is bleeding. An algorithm was proposed to guide management of hematomas and intra-abdominal bleeding after STARR and stapled hemorrhoidopexy. Bleeding is reported in up to 12% of cases. Another study reported bleeding risk as 1.6%. Infection is always a risk with transanal excisional surgery because it is a surgical site contaminated with a lot of bacteria. Infections are usually localized and self-limiting. Possible infections include urinary tract infection, C. difficile infection, and pneumonia. Sometimes, serious infections are possible such as pelvic sepsis (due to sub-peritoneal perforation), or pelvic necrotizing fasciitis. Pain. Pain is one of the most common complications. A few days of pain is considered normal but pain lasting more than 10 days may be a sign of a complication such as infection or dehiscence. Rectal tenesmus is another very common short term complication. Urinary retention. This may be connected to too much fluid given during the operation, or not enough pain relief afterwards. Urinary retention is reported in up to 10% of cases. Dehiscence at the anastomosis (splitting open of the staple line) is the most feared complication by surgeons and is reported in up to 7% of cases. Dehiscence causes pain, bleeding, and discharge. Anastomotic leakage. Accidental closure of the rectum with staples was reported, but is very rare. Vaginal tears are also rare.
Late complications include: