Volume I Number I February (2012) pp 14-20 The Clarion    ISSN : 2277-1697

Video Endoscopic Treatment of Complex Anal Fistula-A New Emerging Treatment modality

Subhash Khanna

Email: [email protected] 

Swagat Endolaparoscopic Surgical Research Institute

Guwahati, Assam, India

Abstract

Video Endoscopic Anal Fistula management is a new and emerging treatment modality.

In this technique a miniature endoscope is introduced through the fistula and the fistula cured by various ablative techniques without causing any harm to the internal sphincter and also without causing a major wound to the patient. The technique is in evaluation but has shown very promising results particularly in the complex and recurrent anal fistulae. In this technique the chance of missing the internal opening of the fistula is very small as the fistula is seen under vision and the technique is truly minimally invasive with no risk of damage to the internal anal sphincter and incontinence. The aim of this chapter is to introduce the technique and the preliminary results of this new treatment modality.

Keywords: Anal Fistula, Video, Fistuloscopy

Introduction

In the last two decades since the introduction of the concept of Minimally Invasive surgery for the treatment of various abdominal disorders the treatment of various benign anorectal diseases has also undergone an unprecedented change. Most of the benign anorectal diseases that were being treated by various conventional surgeries causing great trauma to the patient are now being managed by minimally invasive means. The common benign disorders in the perianal region are Fistula in ano, Haemorrhoids, Peri anal abscess, Anal Fissure and benign tumours.

Fistula in ano is a chronic granulating tract with a primary opening (internal) in the rectum or anal canal and a secondary opening (external) in the perianal skin. Although this definition appears simple, it is far from it. In many instances there may be no internal opening, or there may not be an external opening at all and at times there may be multiple external openings and the track itself may be very complex with multiple side tracts. Multiple internal openings are very rare. The goal of treatment of this common ailment has been to resolve sepsis and symptoms associated with it, and the treatment of resulting fistula without leading to impairment of continence. It has been said that many a surgeon’s reputation has been impugned because of unsatisfactory treatment of this condition, and the surgeon who has the opportunity to treat the patient first is the most likely to effect a cure. Till date there is no single technique appropriate for the treatment of all fistulas in ano, therefore, treatment used to be directed by the surgeon’s experience and judgment. There has been a recent surge of interest in the treatment of this disease process particularly after the advent of collagen and fistula plug and after the introduction of various newer diagnostic modalities viz: endorectal ultrasound and M R fistulography. The most recent revolution in the management of anal fistula is the introduction of the Minimally Invasive Technique of management of fistulas with the help of fistuloscope, introduced by Dr Piercarlo Meinero (Ciavarese, Italy). The Piercarlo concept was that in traditional surgery while removing diseased fibrosed fistula tract excessive amount of normal healthy tissue was being excised leaving the patient with a large wound that takes three to six months for healing. The tract can now be destroyed by endoscopic means, and the internal opening managed by various means causing a healing with much less trauma to the patient. In this chapter we would discuss the technical details and advantages of this technique

Equipment and Instruments

The Video Assisted Anal Fistula Management (VAAFT) kit includes the Meinero Fistuloscope [Fig 1, Meinero Fistuloscope], a monopolar fistula electrode [Fig 2, Monopolar Fistula Electrode] with a high frequency electrosurgical unit, a brush, and a grasping forceps. In addition to these a modified transparent anoscope (THE BEAK, Sapimed, Italy) [Fig 3, Modified Anoscope (The Beak)], a stapler (linear or circular) and 1ml cyanoacrylate glue with an infant feeding tube are also used in the procedure [Fig 4, Cyanoacrylate Glue (Gesica)]. The anoscope available along with the haemorrhoidal PPH kit marketed by Johnson and Johnson can be used in place of special anoscope. Moreover, all cases may not be suitable for transanal stapler closure of internal opening. Presently Transtar Contour (Ethicon Endosurgery) is not available in Asia.


Fig 1: Meinero Fistuloscope
Fig 2: Monopolar Fistula Electrode

Fig 3: Modified Anoscope
Fig 4: Cyanoacrylate Glue (Gesica)

Fig 5: Dye fistulogram - low fistula dye spilling in the sigmoid
Fig 6: Patient position and Drainage pouch

The fistuloscope is a straight and rigid 8 degree telescope with an angled eyepiece having an outer diameter of 3.3mm to 4.7mm and a working length of 18cms; it is autoclavable having an instrument channel diameter of 2.5mm. An anal dilating speculum also forms a part of the standard fistuloscopy kit along with a metallic curette. Apart from this the tract needs to be visualized with the help of a washing solution. The washing solution can be constituted with 1% glycine and 1% mannitol, and 3-5 liter bottles should be kept ready before starting the procedure.

A standard laparoscopic equipment trolley with a xenon light source and a HD camera along with an irrigation device is ideal to have the best quality real time images through the miniature fistuloscope. 

Preoperative Preparation

All patients undergo complete pre anesthetic routine investigations and work up including a sigmoidoscopy (preferably with a methylene blue dye) to locate the internal opening and to exclude any underlying pathology (Crohn’s, Tuberculosis, Malignancy). In the VAAFT technique as the first step is diagnostic fistuloscopy, an expensive MR Fistulogram   is not needed. Some of the patients referred to our Institute have already had a dye fistulogram before being referred to us [Fig 5, Dye fistulogram - low fistula dye spilling in the sigmoid]. Anal endosonography, strongly advocated in recent years for conventional fistulectomy, is also not necessary in the VAAFT technique.

The Technique

Patient positioning and anasthesia:

The technique has two phases, a diagnostic and an operative phase. The patient is taken in a lithotomy position with 15-30 degree flexion at hip joint and the video endoscopic cart and monitor is kept at the level of right or left shoulder. A drainage pouch (trap) similar to the ones used in PCNL is very useful in collecting the irrigating solution [Fig 5, Dye fistulogram - low fistula dye spilling in the sigmoid]. The anasthesia of choice is spinal for complete relaxation of the sphincter, although the procedure can also be done under general anasthesia.

Diagnostic Fistuloscopy

The fistuloscope is inserted through the external fistula opening with the washing solution already running to open up the fistulous opening [Fig 6, Patient position and Drainage pouch] and the tract. Any force used at this stage may lead to the fistuloscope entering the fatty tissue of the buttock, causing severe oedema, and procedure may have to be abandoned. Once inside the tract, the tract can be visualized nicely on the monitor, and if there is any debris or blocking tissue, they can be removed with the help of 2mm graspers [Fig7, Fistuloscope Introduction through external fistula opening]. The external opening can be excised for ease of entry of fistuloscope and the excised tissue may be sent for histopathological examination [Fig 8, The fistula tract visualized]. The fistuloscope is now gently maneuvered along the tract by using left- right and up-down movements and thus side tracts if any are visualized and finally the tip is negotiated through the  internal opening. A finger in the rectum and illuminating light from the tip of the scope seen through the mucosa helps in identifying the internal opening [Fig 9, External opening being excised]. Once the scope exits through the internal opening, two thick sutures are taken, one above and the other below the opening to lift the margins so that a volcano like tissue is created that can be stapled later for closing the internal openings [Fig 10, Tran illumination of the scope through the mucosa].

Operative Phase

The surgeon now starts coagulating the fistula tract under vision with the help of monopolar electrode introduced through the working channel of fistuloscope [Fig 11, Internal opening being isolated]. The entire slough adherent to the fistulous tract and all granulation tissue is completely destroyed. Any branching or abscess cavity or recess is also similarly dealt with. Utmost gentleness in withdrawing the tract wall is needed so that the tract is completely cauterized. After completion of coagulation, the debris in the fistula tract is completely removed with fistula brush and with curettage if very large. The patent internal opening at this stage helps washing of tract, and the fluid and debris are washed into rectum. Now the fistuloscope is completely withdrawn and the modified anoscope introduced, the assistant lifts the internal sutures lifting the internal opening at least 2cm in the shape of a volcano and the surgeon inserts a linear or circular stapler and thus internal opening is cut and sutured [Fig 12, The Electrode destroying the fistulous tract]. In case good volcano cannot be created due to extensive fibrosis around the internal opening, mucocutaneous flaps are created and the internal opening closed meticulously.

Finally, after closure of the internal opening either by stapler or sutures, the internal opening is further reinforced by injecting 1ml of cyanoacrylate with infant feeding tube through the external opening[Fig 13, Internal opening Staple closed]. After the tract is completely cauterized and closed the external tract is gently curetted, so that it remains patent till the fistula is completely healed from inside.

The attendants of the patient are trained to irrigate the tract at least twice a day with normal saline and feeding tube for at least a week. In the post-operative period no special precautions are needed and the patient can get back to work on the 3rd to 5th post-operative day.


Fig 7: Fistuloscope Introduction through external fistula opening
Fig 8: The fistula tract visualized

Fig 9: External opening being excised
Fig 10: Tran illumination of the scope through the mucosa

Fig 11: Internal opening being isolated
Fig 12: The Electrode destroying the fistulous tract

Fig 13: Internal opening Staple closed

Discussion

The traditional surgery for fistula in ano has a very high recurrence rate up to 25% [Lilius H.G (1968)] and the search for the optimal treatment continues. This high recurrence rate may be due to some part of the tract and internal opening not being recognized at surgery [Seow Choen F et al (1992)], inadequate drainage of abscess or false communication formed by injudicious probing, and also at times failure to identify underlying pathology. To overcome the problem of missed tracts several radiological investigations have been attempted in the past with the objective of improving primary and recurrent fistula surgery. Fistulography has been disappointing for several reasons. Chronic tracks may be patent and get filled with dye, but the acute tracts are not so and only part of the tract may be seen. It is very difficult to relate the tract to the sphincter and levator ani, because there is no landmark on fluoroscopy and contrast often refluxes back into rectum giving a fallacious impression [Fig 5]. In one study fistulography was found to be correct and useful in only 16% cases. (Kuijpers HC et al 1985 ), although in selected cases it may alter management and reveal unexpected findings in 48% [Weisman  RI et al].

With the availability of MR imaging it is seldom used. The initial enthusiasm for endoscopic anal ultrasound with a huge detection rate and fistula complexity has not been supported and it was shown to be no more accurate then digital examination of primary tracks. It also failed to show supraelevator collections. [Choen S et al (1991)].MR imaging of fistula has various advantages that include multiplanar imaging and high soft tissue differentiation to show the track system, but fibrosis around the track and a dry track are usually missed by MR. Most of the studies have shown MR imaging to be 84% accurate and endo anal ultrasound as only 60% accurate with specification of 68% and 21% respectively. [Maier  A G  et al (2001)].The technique of using dye to delineate the tract deserves comment. The problem of using a dye with a standard anal proctoscope is that the surgeon may have only one opportunity to visualize the internal opening before the material stains the entire mucosa [Misra MC (1996)]. This method is therefore; unsatisfactory. The technique used by us of dye sigmoidoscopy definitely has several advantages as the internal opening can be seen under vision on gentle withdrawal of flexible sigmoidoscope. Moreover in many cases where the MR imaging has failed to visualize the blocked internal tract and opening, the dye opens it up and thus remains of particular value in patients with no identifiable internal opening. The use of milk or hydrogen peroxide may be more appropriate as it doesn’t stain the mucosa. It appears when the tracts are being visualized with the help of fistuloscope the accuracy would be nearly 100% although at present there is no data available in the world literature on comparative study of fistuloscopy and MR imaging of anal fistula. It seems with fistuloscopy giving a direct view of the tract Endo anal ultra sonography would no more be needed.

Traditionally the treatment of Anal Fistula has been dictated by the amount of sphincter complex involvement and the location of the internal opening. The simple fistulas, low trans-sphincteric and intersphincteric could be treated easily by laying the tract open (fistulotomy) and excising the tracts (fistulectomy). Complex fistulas with multiple tracts, high fistulas, and those related to inflammatory bowel disease used to be treated by more intricate methods and various advanced flap techniques [Klotz HP et al (1993)] and even with temporary or permanent colostomy. The primary surgical approach to successful resolution of anal fistula is appropriately addressing the internal opening, which requires the internal opening to be located with certainty and then either closed securely or being allowed to heal by secondary intentions [Rizzo J.A et al (2010)]. Although fistulotomy is still preferred over fistulectomy which causes a much larger wound and higher rate of incontinence [ Kronborg O 1985], but even with simple fistulotomy the recurrence rate is 2% and 9% with functional impairment between 0% and 17% [Van Tets WF et al (1994)]. Although it is recommended that a simple fistula debridement and fibrin glue injection locally may treat low anal fistulas, but successful healing can only be achieved in 60% to 70% of patients [Cintron JR et al (2000) , Zmora O et al (2003)]. Using this technique healing rates of 14% to 60% can only be achieved in complex fistulas [Cintron JR et al 2000 , Buchanan GN  et al (2003)]. The use of endorectal advancement flap may result in successful healing in 55% to 98% of patients, but [Agvilar PS et al (1985) , Schouten WR et al (1999)] with associated minor incontinence in 31% and major incontinence in up to 12% [ Schouten WR (1999) , Gustafasson  UM (2001)]. Even with Seton technique of staged fistulotomy the rates of minor and major incontinence are significant ranging from 34% to 63% (minor) and 0% to 26% major [Van Tets WF  et al (1995) , Hamalainen KP et al (1997) , Isbister WH et al (2001)] and the time of healing may vary from 1 month to more than a year. Even fistula plug studies failed to achieve results that were reproducible. The major advantage of the biological plug made of lyophilized porcine small intestine mucosa was that it was non invasive and showed promise in sphincter sparing, but success rates were quite low varying from 61% to 71%. [Schwandner O et al (2008), Garg P (2008)].

The Video assisted fistula management technique meets all the criteria of being a minimally invasive technique that is safe and rational. Although initial results have shown recurrence rates to be on the higher side but these were in patients who had multiple surgeries in the past and those having complex anal fistulas that were not amenable to other conventional surgical procedures. Various combinations are being tried to see the outcome and results of combining the technique with Biological plug or laser.

Emerging new Indications of Fistuloscope

The Meinero fistuloscope in future may have wide range of applications. Apart from being used in complex anal fistulas, we have used it in pilonidal sinus and also in a case of cervical sinus after dissection of the tract to visualize the upper limit of the tract [Fig 15]. In future the fistuloscope may become an important tool in managing biliary and bowel fistulas.

Conclusion

Video Assisted Management of Complex Anal Fistula has emerged as a promising new minimally invasive sphincter saving treatment   modality. Although sub mucous fistulas and low inter sphincter fistulas can be treated with fistulotomy and fistulectomy, all recurrent cases (even low) and all doubtful cases should have a fistuloscopy on the operation table prior to proceeding with any surgery. The major advantages of this technique, apart from almost certain localization of internal opening, is the  absence of open wounds, no necessity  for expensive investigations, no need to classify the fistula pre operatively , almost absent post operative pain and very early return to work. The initial results in our hand have been very encouraging but we would have to wait for long term results to come to definite conclusions.

References

Agvilar PS, Plasencia G, Hardy JG Jr,et al. Mucosal advancement in the treatment of anal fistula Dis Colon Rectum 1985; 28:496-8

Buchanan G N, Bartram C I, Philips RK, et al. Efficacy of fibrin sealant in the Management of complex anal fistula: a prospective trial. Dis Colon Rectum 2003; 46:1167-74.

Choen S, Burnett S, Bartram CI, Nicollas RJ. Comparison between anal Endosonography and digital examination in the evalution of anal fistulae.Br.J. Surg 1991; 445-7

Cintron J R, Parkjj, Orsay CP et al. Repair of fistulas-in-ano using fibrin adhesive: long term follow up. Dis Colon Rectum 2000; 43:944-50

Garg P. To determine the efficacy of anal fistula plug in the treatment of high Fistula-in-an: an initial experience. Colorectal Dis 2008

Gustafasson UM, Graf W. Excision of anal fistula with closure of the internal opening: functional and manometric results. Dis Colon Rectum 2001; 45:1672-8.

Hamalainen KP, Sainio AP Cutting sectors for anal fistulas: high risk of minor control defects. Dis Colon Rectum 1997; 40: 1443-7

Isbister WH, Sanea NA, The Cutting seton: an experience at King Faisal Specialist Hospital. Dis Colon Rectum 2001; 44:722-7.

Klotz H P, Buchmann P. Sliding flap-plasty in treatment of anal fistula: A prospective study. Helv Chir Acta 1993; 60:287-9.

Kronborg O. To lay open or excise a fistula-in-ano:9 randomized trial Br. J. Surg 1985; 72:970.

Kuijpers HC, Schulpen T. Fistulography for Fistula-in-ano. Is it useful? Dis Color Rectum 1985; 28:103-4

Lilius H G. Fistula-in-ano, an investigation of human foetal anal ducts and Intramuscular glands and a clinical study of 150 patients Acta chir Scand 1968; 383 (suppl):7-88

Maier A G, Funovics MA, Kreuzer SH et al.  Evaluation of perianal sepsis: Comparison of endosonography and magnetic resonance imaging J.Mag Reson Imaging 2001; 14:254-60

Misra MC. Fistula-in-ano GI Surgery Annual Vol 3, 1996 Editor Dr. T.K. Chattopadhyay

Rizzo J.A, Naig A.L, Johnson E K.  Anorectal Abscess and Fistula-in-Ano Evidence-Based Management Surg Clin N Amer 90 (2010) 45-68.

Schouten WR, Zimmerman DD, Briel JW. Transanal advancement flap repair of Transsphincteric fistulas. Dis Colon Rectum 1999; 42:1419-23.

Schwandner O, Stadler, Dict10, et at. Initial experience in efficacy in closure of cryptoglandular and Crohn’s’ trans sphincteric fistulas by the use of anal fistula plug. Int J. Colorectal Dis .2008; 51 (6):838-43

Seow-Choen F, Nicolls RJ. Anal Fistula. Br. J Surg 1992; 79: 192-205.

Van Tets WF, Kuijpers JH. Seton treatment of perianal fistula with high anal or rectal opening. Br.J. Surg 1995; 82:895-7.

Van Tets W F, Kuijpers HC.  Continence disorders after anal fistulotomy. Dis Colon Rectum 1994; 37:1194-7.

Weisman RI, Orsay CP, Pearl RK, Abcarian H  The role of fistulography in Fistula in ano. Report of five cases. Dis colon Rectum 1991; 34:184-4

Zmora O, Mizrahi N, Rotholtz N et al. Fibrin glue sealant in the treatment of Perianal fistulas Dis Colon Rectum 2003; 46:584-9

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