TREATMENT OF IATROGENIC ANAL STRICTURE

Transcription

1 POLSKI PRZEGLĄD CHIRURGICZNY 2007, 79, 4, /v TREATMENT OF IATROGENIC ANAL STRICTURE TOMASZ KOŚCIŃSKI Department of General, Gastrointestinal and Endocrine Surgery, K. Marcinkowski Medical University in Poznań Kierownik: prof. dr hab. M. Drews Anal stenosis is an abnormal narrowing deformation of the anal canal. The anal canal become unable to extend during defecation, due to tissue cicatrization and loss of elasticity The aim of the study. 1. Careful selection of different anoplasty techniques according to the size and shape of the stenosis. 2. Describing the results of anoplasty operations after 3 months. Material and methods. The study includes 7 patients operated on for critical anal stricture during a 10-year period, with ages ranging from 22 to 76. Anal stenoses were complications of prior anorectal surgery. Seven reconstructive operations were performed. Five conservative excisions of scar tissue using the Y-V anoplasty for covering the tissue defect. In one case of cicatrization after improperly performed Whitehead hemorrhoidectomy, two S-shaped rotational flaps were used. Another patient was treated by radial incision of the stricture and internal sphincterotomy. Results. In all but one patient, durable anal dilatation was achieved. One patient developed late recurrent anal stricture. She was successfully reoperated after 6 years using internal sphincterotomy and a mucosal advancement flap. Conclusions. Various surgical techniques, such as the incision of the scar and internal anal sphincter, removal of scar tissue and covering the defects with well vascularized skin flaps, are available for management of anal stenosis. Early complications like visible wound dehiscence in the donor site or translocated flaps and local infection may occur. In most cases, they are amenable to medical management and do not affect functional results. Key words: anal stricture, anoplasty, iatrogenic anal stricture, recurrent anal stricture Anal stenosis is an abnormal narrowing deformation of the anal canal. The anal canal cannot extend during defecation, due to tissue cicatrization and loss of elasticity. Causes of anal stenoses include inflammatory bowel diseases, infection of the perineal and anal canal regions, trauma and irradiation (1). The mechanism of anal strictures is mostly iatrogenic Iatrogenic stenoses complicate anal operations such as hemorrhoidectomies, fissurectomies, and low anterior resections of the rectum (using ileo-j-pouch anal anastomoses). Anal stricture may also be one of the complications following transanal resection of the rectum. Complications after hemorrhoidectomy include narrowing of the anodermal-margin or the upper part of the anal canal. Strictures of the anodermal-margin are caused by extensive excision of the anoderm or by leaving too narrow mucosal bridges below the dentate line (2). It is said that the mucocutaneous junctions should be at least 5 mm wide. This complication may follow Milligan-Morgan s hemorrhoidectomy, but primarily follows Whitehead operation, which is total excision of the entire tube of mucosal and submucosal vascular tissues with immediate primary suture with the anoderm (3, 4). The strictures above the dentate line are caused by excessive retraction and wrinkling of the mucous and submucous membrane of the rectum during ligation of the he-

2 Treatment of iatrogenic anal stricture 281 Fig. 1. Y-V anoplasty The study included 7 patients operated on for critical anal stenosis from 1996 to There were 5 women and 2 men ranging in age from 22 to 76. The cause of the stenosis was surgical treatment of perianal diseases. Stenosis followed hemorrhoidectomy in 4 patients (2 Milligan-Morgan, 1 Langenbeck, 1 Whitehead), 2 patients underwent fissurectomy and internal sphincterotomy, respectively. One patient suffered from a stricture that was a consequence of congenital anal malformation correction. In childhood, she was treated by the Rhebein method and repeated dilatations under general anesthesia with the anal insufficiency treated using gracilloplasty. In 5 patients, strictures were localized to the mucocutaneous anal verge. In one patient, strictures were localized above the dentate line. In one case, the stricture involving the entire length of the anal canal followed the multistep surgical treatment due to congenital anal malformation (tab. 1). All patients underwent surgery under general anesthesia, antibiotic prophylaxis was romorrhoidal pedicle. Also, excision of the margins of chronic fissure with vertical sutures along the anal canal may lead to stenosis. Stricture may also follow very low resection of the rectum as a result of impaired vascular supply, local infection, inflammation around the staples and anastomotic leakage (5). It may occur if the anastomosis is protected by a stoma. Cicatrization leading to lasting stenosis occurs 2-3 months after surgery (6). It is very important to eliminate the possibility of the neoplastic recurrence within the anastomosis, where the low resection of the rectum was performed (7). The diameter of the stenosis may be objectively measured using Heggar dilators. Principles of surgical treatment The goal of instrumental management are: to restore distensibility throughout defecation, to improve sphincter relaxation, to form an elastic muco-cutaneous junction. An important condition to achieve satisfactory long-term results is to obtain healthy anoderm of proper thickness. MATERIAL AND METHODS Table 1. Profile of anal strictures and their reconstructive operations Patients (age) Prior operations Stricture localization Surgical treatment P.M. (46) Whitehead circular scar, cutaneous margin rotational S flap P.S. (63) Langenbeck above the dentate line radial division F.J. (76) fissurectomy posterior part of the cutaneous margin Y-V anoplasty W.J. (68) Milligan-Morgan circular scar Y-V anoplasty with two flaps* K.M. (60) Milligan-Morgan posterior part of the muco-cutaneus Y-V anoplasty margin K.K. (22) Rhebein operation, divulsio multipl., gracilloplasty entire anal canal Y-V anoplasty with two flaps J.M. (71) internal sfincterotomy, scar excision posterior part of the cutaneous margin Y-V anoplasty * późny nawrót zwężenia odbytu / late recurrence of the stricture

3 282 T. Kościński Fig. 2. Circular stenosis anoplasty using two rotational flaps utinely used and a cleansing enema was performed preoperatively. Seven anoplasties were performed. The aim was to limit the excision only to scar tissue necessary to dilate the diameter of the anus. We covered the resulting tissue defects using an advancement skin flap in 5 patients. Two skin flaps were used in 2 patients with a circular scar. We used the Y-V techniques with a full-thickness skin flap without any subcutaneous tissue or fat. Lateral edges were undermined to facilitate suture without tension. Fig. 3. Method of rotational flap preparation (the skin incision helps obtain the mesh effect and decrease the suture line tension) Hemostasis was achieved using a bipolar coagulation and absorbable polyglycol sutures 2-0. In one case of anal stenosis caused by Whitehaed operation, 2 rotational S-shaped flaps were used to cover the tissue defect. A radial incision was made in one case (male) in 4 points within the upper portion of the internal sphincter above the dentate line. The results were assessed 3 months after operation. RESULTS All patients operated on for critical anal stricture were cured or experienced significant improvement. They required dietetic measures, keeping soft stools and ambulatory care. The anal diameter was regularly controlled and dilated using an index finger. Few suture dehiscence was observed and they generally led to prolonged wound healing without any influence on the functional effect after operation. Satisfactory, long lasting distension of the anal canal was obtained. One patient experienced late recurrence of anal stenosis after using her 2 wide advancement flaps. She was successfully reoperated after six years by incising the cicatrized internal sphincter and using an island flap anoplasty.

4 Treatment of iatrogenic anal stricture 283 DISCUSSION Anal stenosis is a very important scaring complication of anorectal surgery, not easily cured effectively. Good knowledge of its pathomechanism makes it less frequent (2). The ideal procedure should be simple, effective, and free from serious morbidity and should restore the anal function for a good longterm outcome (3). When the stricture occupies only a portion of the anal circumference, the Y-V anoplasty or differently shaped flap advancement techniques should be used (3, 6, 7, 9). In patients with coexisting fibrosis of the internal sphincter, sphincterotomy is also indicated (6, 10, 11). The groups ranging from 4 to 149 patients treated surgically for anal stenosis are described in the literature (3, 6, 8, 10-14). All authors unanimously report that anoplasty with one or two advancement Y-V flaps is a highly effective method with results ranging from qualitative measures of good and very good ranging from 91 to 100% (3, 10, 11, 13). The recurrence of stricture are noted only in a few patients and complications include suture line dehiscence in a skin-graft place and anastomosis failure both due to loss of vascular supply to the advancement flap. All above mentioned techniques do not need surgical reoperation and are successfully conservatively managed (3, 13). Internal sphincterotomy as a major treatment was used by authors from Singapore (12). Milson and Mazier achieved good results in 83% of patients treated by a single or multiple internal anal sphincterotomies in case of middle or upper anal canal stenoses (14). Carditello, Aitola and co-authors used mucosal advancement flap anoplasty combined with internal sphincterotomy (10, 11). Circular anal stenosis needs a circumferential scar excision and formation of two wide rotational flaps for covering the tissue defect. They are taken within the buttocks limits and grafted to the anterior and posterior part of the anal canal. Hudson used S-plasty for the treatment of anal stricture after Whitehead s operations. He noticed that this technique requires a longer hospital stay and is associated with a higher risk of local complications (4). Singh and co-authors observed flap donor site break down in 60-70% of patients operated on for anal strictures complicating surgical treatment for chronic anal fissures (15). In the group of 21 patients treated with the use of a rotational flap from perianal skin, only 2 (9.5%) revealed a donor site complication and 1 suffered from suture dehiscence of the advancement flap. All of these problems were successfully managed conservatively. Good functional results achieved by the above mentioned author are the result of: careful selection of different anoplasty techniques according to the size and shape of the stenosis, preserving a good vascular supply for the advancement flap and no excessive tension in the suture line. Postoperative, ambulatory treatment is also very important and requires stool softening (liquid stools should be avoided) and systematic examination of the anus using a lubricated index finger to achieve permanent dilatation of the anal diameter. CONCLUSIONS 1. Various surgical techniques are available for management of anal stenosis. Single or radial incision of the scar together with internal anal sphincter is a viable option. Anal stenosis may be successfully treated by removal of scar tissue and covering the defects using well-vascularized skin flaps. 2. Often, visible wound dehiscence in donor site or in translocated flaps and mild local infection may occur. In most cases, they are amenable to medical management and do not affect functional results. REFERENCES 1. Galandiuk S, Kimberling J, Al.-Mishlab TG et al.: Perianal Crohn disease: Predictors of need for permanent diversion. Ann Surg. Proceedings of the 116 th Annual Meeting of Southern Surgical Association. 2005; 241, 5: Brisinda G: How to treat hemorrhoids. Prevention is best, hemorrhoidectomy needs skilled operators. BMJ 2000; 321: Maria G, Brisinda G, Civello IM: Anoplasty for the treatment of anal stenosis. Am J Surg 1998; 175;

5 284 T. Kościński 4. Hudson AT: S-plasty repair of Whitehead deformity of anus. Dis Colon Rectum 1967; 10: Thorson AG, Blatchford GJ: Anorectal strictures. Medycyna Praktyczna 1999; 1, 13: Angelchik PD, Harms BA, Starling JR: Repair of anal stricture and mucosal ectropion with Y-V or pedicle flap anoplasty. Am J Surg 1993; 166(1): Marti MC: Anorectal strictures. In: Surgery of anorectal diseases. Marti MC, Givel JC. Springer- Verlag Berlin, Heidelberg 1990; Pearl RK, Hooks VH 3rd, Abcarian H et al.: Island flap anoplasty for the treatment of anal stricture and mucosal ectropion. Dis Colon Rectum 1990; 33, 7: Stratmann H, Kamiński M, Landschke H et al.: Plastic surgery of the anorectal area. Zentralbl Chir 2000; 125(2): Aitola PT, Hiltun KM, Matikainen MJ: Y-V anoplasty combined with internal sphincterotomy for stenosis of the anal canal. Eur J Surg 1997; 163(11): Carditello A, Milone A, Stilo F et al.: Surgical treatment of anal stenosis following hemorrhoid surgery. Results of 150 combined mucosal advancement anal internal sphincterotomy. Chir Ital 2002; 54(6): Eu KW, Teoh TA, Seow-Choen F et al.: Anal stricture following hemorrhoidectomy: early diagnosis and treatment. Aust NZJ Surg 1995; 65(2): Pidala MJ, Slezak FA, Porter JA: Island flap anoplasty for anal canal stenosis and mucosal ectropion. Am Surg 1994; 60(3): Milson JW, Mazier WP: Classification and management of postsurgical anal strictures. Surg Gynecol Obstet 1986; 163(1): Singh M, Sharma A, Gardiner A et al.: Earl results of a rotational flap to treat chronic anal fissures. Int J Colorectal Dis 2005; 20(4): Garcea G, Sutton CD, Lloyd TD et al.: Management of benign rectal strictures. Dis Colon Rectum 2003; 46: Received: r. Adress correspondence: Poznań, ul. Przybyszewskiego 49 COMMENTARY A true anatomic stenosis of the anal canal may result from almost any condition that causes scarring of the anoderm, including surgical interventions, trauma, inflammatory disorders and radiotherapy (1). Although the exact incidence of anal stricture has not been determined, about 30-60% of cases are due to haemorrhoidectomy. Even using contemporary techniques, the procedure is associated with a risk of anal stricture of 0 to 1.5% (2, 3). Mild to moderate non-malignant stenosis of either aetiology can usually be managed conservatively with stool softeners combined with anal dilatation techniques. However, in severe cases, surgery is the only therapeutic option. Numerous surgical techniques have been developed, but most of them adopt either rectal mucosa or perianal skin flaps to provide additional healthy tissues into the anal canal. Although some authors advocate lateral internal sphincterotomy, the procedure has not gained common acceptance. Since there is no single recommended approach, the surgeon must select one of the available operations for an individual patient according to the type, location, and extent of the stenosis (2, 4). Y-V advancement flaps are particularly useful for low strictures below the dentate line. However, a potential disadvantage of this technique is that the narrow part of the flap may be insufficient for a significant widening of strictures and is subject to ischemic complications (5, 6, 7). Some other techniques, e.g. the house or diamond flaps, may be required for long strictures and those above the dentate line. When large areas of skin are necessary, a S-rotational plasty may be the best alternative since it ensures adequate blood supply, avoids tension, and can be performed bilaterally (8, 9). The Author of the study described results of anoplasty procedures in 7 patients with critical anal stenosis. This article is very interesting since very few clinical studies have been published. The Author primarily performed procedures with Y-V advancement flaps, along with one S-rotational plasty and one radial in-

6 Treatment of iatrogenic anal stricture 285 cision. In 6 cases, long-term results were satisfactory and only one patient required reoperation. These observations clearly support the validity of such repairs and are in line with reports from other centres. Additionally, clear and descriptive drawings enclosed with the manuscript further increase its value. Even if the incidence of anal strictures is not very high, for further clinical studies one should consider the need for an objective assessment of longterm results with manometric examinations and quality of life measures. REFERENCES 1. Milson JW, Mazier WP: Classification and management of postsurgical anal stenosis. Surg Gynecol Obstet 1986; 163(1): Liberman H, Thorson AG: How I do it. Anal stenosis. Am J Surg 2000; 179(4): Ramcharan KS, Hunt TM: Anal stenosis after LigaSure hemorrhoidectomy. Dis Colon Rectum 2005; 48(8): Lagares-Garcia JA, Nogueras JJ: Anal stenosis and mucosal ectropion. Surg Clin North Am 2002; 82(6): Aitola PT, Hiltunen KM, Matikainen MJ: Y-V anoplasty combined with internal sphincterotomy for stenosis of the anal canal. Eur J Surg 1997; 163(11): Angelchik PD, Harms BA, Starling JR: Repair of anal stricture and mucosal ectropion with Y-V or pedicle flap anoplasty. Am J Surg 1993; 166(1): Gingold BS, Arvanitis M: Y-V anoplasty for treatment of anal stricture. Surg Gynecol Obstet 1986; 162(3): Ferguson JA: Whitehead deformity of anus, S- plasty repair. Dis Colon Rectum 1979; 22(5): Oh C, Albanese C: S-plasty for various anal lesions. Am J Surg 1992; 163(6): Prof. dr hab. Jan Kulig I Katedra Chirurgii Ogólnej i Klinika Chirurgii Gastroenterologicznej CM UJ w Krakowie