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Minimal invasive Endoscopy Procedure for Fistula in Ano

Minimal Invasive Endoscopy Procedure for Fistula in Ano

Dr. Shantikumar D. Chivate MS, FCPS, FICS, FAIS, FACRSI, Dr Laxmikant D. Ladukar , MS. FICS. FACRSI Dr. Meghana V.Chougule M. D.

Jeevan Jyot HospitalOpposite Shahu MarketNaupada, THANE 400602Maharashtra, India

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Objectives: To assess the value of endoscopy in the outcome of treatment of the anal fistula. A Cystoscope was used to visualize anal fistula tract & find out its branches, internal opening & abscess cavities. The acute curved fistulae were converted in to segments and curetted.

Patients:- During the period between 2003 & 2009, 64 complex cases of fistula in ano were operated with minimum invasive endoscopic procedure. In the 64 cases 42 were high, 6 were horse shoe and 16 were recurrent fistula. The series included 51 males and 23 females; average age was 37.5 years ranged between 18 to 56 years of age.

Method:- In the fistula methylene blue and hydrogen peroxide was injected to assess and stain fistula tract, its branches and internal opening. A guide wire or No. 5 ureteric catheter was introduced in the fistula & kept as guide in the long & curved fistula. The dilatation and fistuloscopy was done to facilitated viewing interior of fistula. The tract having acute curve, an extra opening was made at the tip of cystoscope at acute curve. The curve segment was converted in two or three straight segments by dividing fistula tract. The branch found on fistuloscopy a No.18 needle was passed under cytoscopy vision and another guide wire was introduced through the needle in to branch. The whole tract and branches were curetted. The internal opening was sutured. All tracts were packed through perineal wounds of one centimeter diameter.

Results: Patients were followed to see the incidence of recurrence, effect of surgery on continence. Overall recurrence rate was (6 cases) 9.3% in above series. No incontinence was observed. Wounds healed in 8 – 15 days. An infant tube was inserted in the tract and every day tract was irrigated with diluted povidone -iodine without hydrogen peroxide. No pain was observed in post operative period & on dressing.

Conclusion;- In modern era, treatment of fistula should be committed to non touch technique to anal sphincter, The minimal invasive procedure is useful to reduce healing period and eliminated post operative excruciating painful dressing and potential danger of incontinence.


Key wards:- Fistuloscopy. Curved fistula converted in to segments. Detect branches, Curetting, Suturing of internal opening





Fistula-in-ano is one of the common but tedious problems in surgical practice. Anatomically they are classified as, low or high, simple or complex, inter-sphincteric, trans-sphincteric, and supra-sphincteric or extra-sphincteric fistula (1). The high fistulae account for low (8-10 %) & low fistulae for high incidence 90- 92 % (2). The low fistulae are satifactory treatment by conventional laying-open procedure or ablation of fistula tract and internal opening (3, 4).  High fistula-in-ano includes high trans-sphincteric, supra sphincteric and extra sphincteric; are difficult to treat since the conventional procedures will lead to damage major part of the anal sphincter resulting incontinence. In recurrent fistulae presenting with totally distorted anatomy and difficult to trace missed part of tract in previous surgery. (5) Repeated failure of operations is the rule rather than the exception. The digital palpation usually cannot help to distinguish between scar tissue due to repeated surgery and indurations due to extension of disease.


The ultimate goal of fistula surgery is to keep right balance between eradication of infective tract and preservation of anal sphincter function. To achieve the objective in high anal fistulae, different surgical techniques have been in practice. These include Park’s fistulotomy ( 6 ) use of a seton ( 7 ) two-stage-fistulectomy ( 8 ) primary fistulectomy with occlusion of the internal opening, ( 9 ) fistulotomy with primary repair of the sphincter, ( 10 ) endorectal advancement flaps, (11, 12 ) ano cutaneous advancement flap, ( 13 ) & healing of fistula by using fibrin adhesive glue ( 14 ). LIFT procedure recently modified by Dr Rajanukul, is good for closure of internal opening of fistula but the rest of fistula is dealt by routine procedure (15, 16).VAAFT newly developed experimental procedures had been promoted by industry for complex fistula treatment. (17) The multiple procedures used in treatment of fistula indicate that, not a single procedure of treating complex fistulae is satisfactory.


Main problem in treatment of these fistulae is tracing  the tracts and their branches. MRI is good guide in fistula treatment with false positive and negative draw backs. MRI findings are very difficult to correlate on operation table. We used a cystoscope to inspect the main tract and identify its branches in complex fistulae. The fistula tract and their branches were curetted and all inflammatory epithelium is removed up to internal opening. The internal opening was closed with sutures. The study presents the minimal invasive endoscopy procedure used in the treatment of complex fistula and the results; in context to recurrence rate, postoperative continence and operative and post operative pain during dressings.



During the period between January 2003 to July 2009; 64 patients of high / complex fistulae were treated by minimal invasive endoscopy procedure at referral center for fistula, Jeevan Jyot Hospital Thane.

Detail history about the disease, operation and incontinence was noted.  Information about    mode of onset, duration of illness and any previous treatment for intestinal disease like tuberculosis, ulcerative colitis and Crohn’s disease were collected.

Clinical examination, routine investigations, proctoscpy & sigmoidoscopy was performed to search abnormalities like; malinancies, internal opening or hypertrophied anal papilla fibrotic thickening at dentate line.  In all the patient manometry was done and recurrent fistulae were submitted to MRI. The follow up was conducted weekly after healing of fistula wound, for 4 weeks, later on monthly for 6 months and later on yearly on contact.

The patients suffering from pulmonary tuberculosis, gastrointestinal tuberculosis and

Inflammatory bowel disease & Crohn’s disease were excluded from the series.


The technique was discussed in the ethical committee of the hospital and permission was granted to implement to patients. The procedure was discussed with the patients and informed consent was obtained.




Patient was positioned in lithotomy under spinal anaesthesia. The perineal area was prepared as usual. An infant feeding tube of size no. 5 was negotiated into the external opening till it enters smoothly. Injection of hydrogen peroxide and methylene blue of equal amount was injected through the tube under uniform moderate pressure & with compression on external opening. The mixture was started flowing either by the side of the tube or through the internal opening. The injection should reach to all the branches of the fistula. A guide wire of PCNL was passed from external opening to internal opening without force, to avoid creating false passage. Around external opening of fistula a circular incision of one centimeter diameter was taken. On the guide wire PCNL dilators were passed one by one in increasing size, till dilator of 22 Fr. These dilators are sharp and they scrape inflammatory tissue and dilate fistula tract.

A cystoscope was used with 20F sheath with 30 degree telescope and irrigation of saline was used as routine. (Figure No 1 & 2). In the fistula whitish pink- blue fibrous strands were seen and occasional blue stained inflammatory tissue was noted. The scope could reach to the internal opening. In some cases during fistulscopy huge blue cave like opening or washed white branch of tract was noted.  (Figure No. 3). In such blue cave or white hole, a No. 18 needle was passed through perineum in to the hole under the cystoscopy vision. The PCNL guide wire was passed through needle into the branch. A fresh opening of one centimeter diameter was created on the skin around the needle. The dilatation procedure was repeated, the PCNL dilators were passed up to blunt end of the branch. The fistula tract, its branches and their extensions were visualized.  In case of acute curved fistula the tract, it was opened at the acute curve and further tract visualized through new opening. The acute curved tract was divided in two or occasionally more segments (Figure No. 5). The fistula tract & its segments and all branches were curetted through openings on the perineum. The internal opening and underneath mucosa around it was curetted, through the tract on the index finger in the rectum as guide. The internal opening was separated & adhesions were removed by sharp curette and it was elevated as flap. The curetted material was submitted for histology. The Curetting helped in dissection of internal opening in sub mucosal plane as flap and freshened its edges. The internal opening was closed along with internal sphincter, with three zero polyglyactin sutures.  In case internal opening of the fistula was absent a PCNL probe was passed in to the fistula from the external opening and dilatation was done up to rectal mucosa. In some cases fistula tract was continued 2-4 centimeters above internal opening. In all cases post operative antibiotics, anti-inflammatory and analgesic medicines were administered for a week.


Fistula tract and its branches were packed with roller pack, soaked with povidone iodine.             ( Figure No 6 )

Post operative pack / packs were removed after 48 hours. After removal of packs, an infant tube was passed in the wound of each segment of the tract & irrigated daily with diluted povidon iodine with saline till they were healed. No hydrogen peroxide was used.


In the series of 64 cases, 42 were suffering from complex, 6 from horse shoe & 16 from recurrent fistulae. The average age was 37.5 years ranged between 18 to 56 years of age. The series included 41 males and 23 females. In 16 recurrent fistulae 5 cases were operated once, 6 cases were twice and 5 cases were more than twice.  External openings were present in all cases. In 48 cases one, 16 cases two, in 4 cases three external openings were present.Duration of the illness was ranged between 6 months and 12 years (average 45 months) Histology examination of previous operation revealed inflammatory pathology in all cases of recurrent fistulae. In all patients routine investigations were normal except 11 cases, were suffering from diabetes.  Proctoscopy and sigmoidocsopy did not reveal any abnormal findings. The manometery study did not suggest any impairment in continence in any case in the pre or postoperative period.

The endoscopy and guide wire probing revealed internal opening in all cases. In 9 cases one, in 23 cases two, in 28 cases three & more than three in 4 cases tracts were detected.  In 11 cases intersphicteric tract was extended upward 2-4 Cm. beyond internal opening.

The wound healed in ten days in 21 cases, in 14 days in 46 cases and in 21 days in seven cases. In our series out of 64 cases 48 healed at first operation. In 10 cases one of the segments remained non healed. They healed after repeat curetting. The pain was minimum in all cases during the post operative period and dressings. In all cases post operative antibiotics, anti-inflammatory and analgesics were given. The patients operated for recurrent fistula had surprised experience of nearly no pain as compared to previous surgery. Visual pain index was not charted.

In six cases recurrence was noted at end of six weeks. All cases requested to do same procedure. The follow up was done from 2004 to 2011. Minimum follow up was for two years.



Anal fistula is irritable and notorious disease for surgeon and patient both. It has minimum pain till surgical intervention. The goal in the treatment of anal fistulas is to eliminate the fistula without a change in continence which is only possible by non touch technique to external anal sphincter muscles. No single technique exists that is appropriate for the treatment for all types of fistulas. Options include fistulotomy, use of setons, fibrin sealant, and advancement flaps. Recently, a bioprosthetic fistula plug has been described. There had been no satisfactory treatment available. The high / complex and recurrent fistula are less common but difficult to cure. Conventional laying-open technique in high perianal fistula may involve injury to part or whole of the sphincter muscle impairing continence. (18)  It is quite obvious that the more the extent of anal muscle division, greater the degree of chances of getting anal incontinence (19). The use of seton as a drain and staged interventions at short intervals to allow healing of the tissues between each seton application. Healing time is less and continence and shape of the anal canal is preserved (20). Traditional surgical techniques, namely fistulotomy and seton technique, will cause severe damage to internal anal sphincters and may damage the external anal sphincters too. The recurrent rate of “lay-open” fistulotomy was reported to be 2%-9% with functional impairment ranging from 0%-17% (2, 4). The use of a seton has a recurrence rate of 0% - 8%. Minor and major incontinence is 34% - 64% and 2% -26%, respectively (7, 20, 21, 22).

Other alternative approaches are the application of fibrin glue and fistula plug. Since 1999, several studies on fibrin glue treatment of anal fistula have been published. The healing rate after debridement of the tract and fibrin glue injection is 14% - 60% (14, 23).  The continence may not be affected. Fistula plug, another recent technique for complex fistula in ano repair, has a reported failure rate of 13%, and success rate of 83% with a median follow-up of 12 months, is reported for high cryptoglandular anal fistulas. (24, 25)



More recent modified technique of LIFT is good for closure of internal opening but treating rest of procedure for fistula remains same. The LIFT procedure seems to be limited to the transsphincteric fistula. The LIFT procedure for a high transsphincteric or suprasphincteric fistula may be technically difficult.  Interestingly, another intersphincteric approach for the treatment of a complex anal fistula has been described by Matos et al.(16). Rojanasakul, (15) reported two major differences between the LIFT and the previously described technique. There is no provision for detecting additional tracts or branches, which are likely to miss. The added complications like infection of intersphincteric space, abscess formation and adhesion of internal sphincter can cause functional impairment. Recurrence rate varies between 26 to 12% (15, 16)

Vaaft is an innovative procedure developed by an industry. In the new procedure a straight & rigid endoscope with 8 degree optic, is used for diagnosis of fistula tract and its branches. The 8 degree optic is good for forward view and it would miss branches, which are particularly 90 degree or more angles going in backward direction to insertion of scope and the scope will get lost in cavity of abscess. The straight and rigid scope will not adapt or negotiate acute curves of tract. In our series we used to open the tract at acute curve and convert it in to straight or less curved tracts. The optic used by us was of 30 degree which was able to diagnose side branches in any directions. We had identified, in 9 cases one, in 23 cases two, in 28 cases three and more than three branches in 4 cases out of 64 cases operated ( Figure No. 3). In 136 complex fistula cases, vaaft could diagnose in 91 cases (92.8%) the fistula tract was single, whereas in 7 cases (7.2%) it was double.

Occasionally some branch of the tract was negotiated through sphincter complex by dilating up to 22Fr. size (5m.m) would not disturb continence. The sphincter can tolerate 30% loss of the mass without disturbing function. (18)

In VAAFT for the treatment, high radiofrequency energy under water was used.  It is possible to penetrate at least 2-3 mm. of wall of fistula tract. The radiofrequency achieves tissue destruction by two methods: electric current or spark and secondly by producing heat. This heat production is uncontrolled and a lateral spread of this heat also destroys normal tissue unseen on gross examination. This leads to a larger area of tissue damage than intended (26, 27). This penetration of energy will cause more necroses and will get detachment of slough later on, in a week or two. In our series curetting of tracts & its branches was done, which assist in creating raw inner surface of tract and healing. The more pathways created on the perineum would assist in drainage of the fistula rather than infecting them.

In the fistula treated with vaaft, tract was kept open for drainage but no process is implemented for the clearance of the slough detached & collected in side after 1 – 2 weeks. The tract was kept on discharging debris for 2 – 3 months. In the series of 136 cases, 72 cases primary healed after 2-3 months. The tract which was kept open for secondary healing cannot be called primary healing. It is difficult to convince that, how a wound of 3- 5 mm size remained open for 2-3 months and later on how it healed. In 2-3 months fistula would redevelop. Over all healing of fistula in the innovative series of 136 patients, 52 ( 38.2%) healed at the end of one year and 84 (61.7%) cases there was no information as they were lost to follow up.( 18  ) In our series we curette the tract and its branches and give daily irrigation through an infant feeding tube passed into the tract.  The wounds were healed in 21 cases in 10 days, in 46 cases in 14 days and in seven cases in 21 days. Over all wounds were healed in 2- 3 weeks. The vaaft is in experimental stage requires to address basic optics, energy source and rigidity of the scope.


The vaaft is exclusive instrument for fistula treatment is at least 5 times more costly than that of cystoscope. The cystoscpe can be useful in general, urology and gynecology surgery too. The specific instrument for such high cost with unpredictable initial experimental result has to wait, before it makes any impression in the treatment of fistula.


The stapling of internal opening by creating volcano is difficult as there was no dissection of mucosa underneath and more mucosa is excised due to stitches and stapler; will create tension on staple and likely dehiscence. In the minimum invasive procedure the sharp curette separated the rectal mucosa around internal opening like a flap and freshens its edges. Simple suturing of the internal opening was successful in closure. In the series classification of fistula was not possible on endoscopy or anatomical correlation to external sphincters.

The procedure is minimum invasive than the traditional procedures with less or no pain  Options available were either too painful, mutilating  or having high recurrence. The less painful alternative like vaaft is not proved in their experimental study. With new advent of Minimal Invasive   endoscopy surgery, there is change in the treatment of fistula in ano. MIS for anal fistula can be treated nearly with minimum cut, wound, pain or fear of incontinence. In the minimum invasive procedure for fistula; cystoscope was used to find out the branches and extension of the tract. Due to funnel shape arrangement of pelvic muscle and tubular shape of intersphincteric space the long and high fistulae are curved. They are difficult to negotiate by rigid scope. All  acute curves can be made straight tracts if they are divided in segments. The treatment of each segment is valued separately. Even out of three segments one segment may not heal, is easier to treat that segment later on.

Fistula in ano is a common condition that often recurs despite adequate surgery, usually because of tract that was missed at surgery. It is now increasingly recognized that preoperative imaging can help identify infection that would have otherwise gone unidentified. In particular, magnetic resonance imaging findings have been shown to influence surgery and   diminished the chance of recurrence. Anyhow interpretation of MRI during surgery on table is difficult. There are certain falls positive and false negative entities, limits use. (28) Due to endoscopy identification of tracts and the branches fistula treatment will be more complete and confidant.

The radical excision of fistula procedure use to cause excruciating pain and potential danger to impair the function. Healing in such procedure was required long duration and every day unbearable pain during dressing. In minimum invasive procedure healing is faster than other procedures. Patients accept procedure well and in the event of recurrence they demand for the same procedure. It requires no excision of fistula or fibrous tissue in recurrent fistula. There is no disturbance of fibrosis of fistula tract which preserves continuity of sphincter muscles and continence. In the minimum invasive procedure there is no potential danger of injury to the anal sphincter muscles.


In practice fistula surgery leads to radical excision & large wounds at anal and perianal region which leaves patient in severe post operative pain and pain during dressings. These procedures are associated with of deformities due to excision of tissue and scaring. Patient requires long hospitalization for 6 – 8 days or longer. Dressing is required for long time 4- 6 weeks / months. In spite of all these agonizing problems there is high risk of recurrence and incontinence. The Minimum Invasive endoscopy surgery for fistula depends on skill of fistuloscopy which has very short learning curve. The procedure requires one day hospitalization, no radical excision of tissue, no potential danger of incontinence, no painful dressings and heals in short duration. A new procedure had minimum of 2 years follow up, had proved its efficacy. It had 91 % success rate in difficult problems like high, long, complex recurrent, horse shoe fistula. It is choice of the patient even after recurrence. Non touch technique to anal sphincter is the present policy to treat fistula surgery and the procedure is fitting in it.



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Fig. No 1 complex fistula





Fig. 2 fistuloscopy




Figure No 3 Fistuloscopy view;  Black arrow --branch, White straight arrow-- Main tract, Curved white arrow -- small abscess




Fig. No. 4  fistuloscopy marking of   fistula tract





Fig. No. 5 Tract opened at acute curve of fistula


Fig No. 6 All segments of tract packed