27 J I M D C   2 0 1 7  27 

Op e n  Ac c e ss  
F u l l  L e n g t h  A r t i c l e  

Management of Fistula-In-Ano: A local Experience 
M Fahim Ahsan1, Haider Darain2, Aatik Arsh3, Muhammad Ibrar4 

1 Senior Registrar, General Surgery Department Pakistan Institute of Medical Sciences, Islamabad 
2 Assistant Professor, Khyber Medical University Institute of physical Medicine and Rehabilitation 

3 Paraplegic Center Peshawar 
4 Isra University, Islamabad Campus 

A B S T R A C T  

Objective: To evaluate short and long-term outcomes of complex fistula surgery.  

Patients and Methods: This cross-sectional study was conducted on all patients, both male and female admitted to 

General Surgery Department of PIMS, Islamabad who underwent surgery for fistula-in-ano from 1st January 2010 to 

31st December 2015. A total of 65 patients, who underwent surgery for fistula-in-ano in the hospital were included in this 

study. They were assessed by case review supplemented by OPD follow up and telephonic interview when necessary.  

Results: A total of 65 cases of fistula-in-ano were operated in the surgical unit of the hospital. Out of the total patients, 

27 patients were operated once, 29 patients were operated twice and 9 patients had surgery three times. Almost about 

half of the patients (45 %) had trans sphincteric complex fistula with secondary tract identified in 40% cases, 16 % cases 

with intra sphincteric, 36% cases with extra sphincteric, 3% case with horseshoe shaped and 5% with a combination of 

two. In 45 % of the cases, excision of primary and secondary tracts were done with loose seton placement while 

preserving the sphincter complex. About 36 % cases had excision of the tract while in horseshoe cases fistulotomy was 

done. In 4 % of cases primary excision of the tract and repair of the sphincter complex was performed. In two patients, 

drainage and curettage of presacral abscess was done. We made colostomy in one patient after 4th recurrence while 

one patient was having colostomy before operation that was operated 6 times for fistula. No incontinence was reported 

for solid and liquid, while 12.3 % cases had transient flatus incontinence, 9.2 % cases presented post-operative bleeding 

in which 4 % of patients settled with pressure dressing while 5.2 % required control of bleeding under GA. 

Conclusion: Majority of the complex fistula in-ano treated by primary fistulotomy or stage fistulotomy with a loose seton 

are followed by good clinical and functional result. 

Key words: Fistula in ano. Fistulotomy, Fistulectomy, Loose seton 

Author`s Contribution 
1Conception, Synthesis and Planning of the 
research, 2,3,4Interpretation, analysis and 
discussion 

Address of Correspondence 
Dr Haider Darain                              
Email: haider.kmu@hotmail.com 
 

Article info. 
Received: Nov 28, 2016 
Accepted: Mar 18, 2017 
 

Cite this article: Ahsan MF, Darain H, Ibrar M. Management of Fistula-In-Ano: A local 
Experience.JIMDC. 2017; 6(1):27-30. 
 

Funding Source: Nil 
Conflict of Interest: Nil 

I n t r o d u c t i o n  
 

Fistula-In-ano (FIA) has been a common surgical ailment 

reported since the time of Hippocrates but little systematic 

evidence exists on its management.1 A complex FIA is 

defined as a fistula whose treatment poses an increased 

risk of change incontinence, multiple external openings, 

indurations felt above the puborectalis, on probing from 

external opening tract travel towards the levatorani 

instead of anus, when tract involve greater than 30% to 

50% of the sphincter mechanism and is anterior in woman 

or the patient has a history pre-existing incontinence, 

crohn’s disease or local irradiation.2 Infection developing 

in an anal gland lying within the submucosa of the anal 

canal is a direct cause of most FIA(cryptoglandular 

fistula).3 It can be associated with number of conditions, 

including tuberculosis, crohn’s disease and malignancy.4 

O R I G I N A L  A R T I C L E  

mailto:haider.kmu@hotmail.com


 

                           28 J I M D C   2 0 1 7  28 

The estimated prevalence of nonspecific FIA is 8.6 to 

10/100,000 of the population per year, with a male to 

female ratio of 1.8:1.5 It is a distressing condition for the 

patient and can be surgically challenging.6 In 1976, Sir 

Alan Parks classified FIA depending on the relationship of 

the tract to the anal sphincter. In total, four types of tracks 

were described, inter-sphincteric (45%), trans-sphincteric 

(29%), supra-sphincteric (20%) and extra-sphincteric 

(5%).6 Results of treatment of FIA are still far from 

satisfactory, even in centers experienced in its treatment.7 

Recurrence rate varies from 0% to 32% and the incidence 

of postoperative gas and stool incontinence may reach 

63%.7 Present study was designed to evaluate, the short 

and long term outcomes of complex fistula surgery.  

    P a t i e n t s  a n d  M e t h o d s  

A total of 65 consecutive patients who underwent surgery 

for FIA between 1st January 2010 to 31st December 2015 

were included in the study. Our analysis included the 

following parameters: patient’s gender and age, duration 

of symptoms, types of FIA and also the number of single- 

and multi-tract FIAs (including horseshoe-shaped 

fistulas). Detailed medical history was obtained prior to 

surgery, focusing on previous proctological procedures for 

conditions other than FIA. We analyzed the kind of 

surgical procedures most often associated with particular 

types of FIA, other proctological procedures performed 

simultaneously for concomitant diseases, as well as types 

and incidence of early and late postoperative 

complications. We also assessed the effectiveness of 

surgical techniques implemented in the treatment of 

particular FIA types and duration of hospital stay 

associated therewith. Prior to surgery, all patients 

underwent digital rectal examination and proctoscopy to 

localize the internal opening of their fistula and to 

evaluate large-bowel mucosa for any coexisting diseases. 

Whilst most complex fistulae require the use of imaging 

modalities such as contrast fistulography, or magnetic 

resonance imaging to correctly classify the primary and 

secondary tract, the level of internal opening and 

associated pathology. Almost 85% can be correctly 

diagnosed by careful examination under anesthetic and 

the judicious use of probes. 

All procedures were performed by a specialist general 

surgeon. Early in the series, spinal anesthesia was 

predominated; Full relaxation was avoided to enable the 

surgeon to appreciate the extent of the anorectal ring. 

When the internal opening was difficult to identify, either 

dilute methylene blue or hydrogen peroxide was injected 

through the external opening to assist its localization. The 

operative procedures included simple fistulotomy (laying-

open technique), fistulectomy of secondary tract cutting 

seton technique (sequential office-based seton 

advancement), and draining seton technique. The 

draining seton patient had placement of the seton as if 

prepared for the cutting technique. However, the 

fistulotomy was maintained without tightening for at least 

5 weeks or until the inflammatory response receded. At 

this point, EUA was done and the seton was removed, 

and the patient was followed-up expectantly. Post-

operatively, the wounds were managed by twice-daily 

digitation and irrigation rather than by tight packing. 

Patients were followed up on the ward 3rd day and 1st 

week after surgery. This allowed the wound to be 

inspected and checked for postoperative bleeding and 

infection. Thereafter, patients were seen in outpatients on 

weekly basis for 1st month than fortnightly up to 6-monthly 

interval at our Outpatients’ Clinic, until fistula was healed. 

Thereafter, Patients were assessed for symptoms and 

signs of recurrence and also for incontinence if needed.  

There was a template for the examining doctor to fill in 

when the patient attended for review. It included wound 

infection, wound healing period, digitations done 

continence disturbances, stenosis and recurrence of 

fistula. 

R e s u l t s  

A total of 65 patients underwent surgery for complex 

fistula during 5 years’ study. They were assessed by case 

review supplemented by OPD follow up and telephonic 

interview when necessary. The mean age of these 

patients was 45.3 years ± 9.3 SD. Out of total, 58 (89%) 

patients were male while remaining 11% (n=7) were 

female. The patients were clinically proven to FIA for a 

mean of 11.5 month. (Range =1 to 60 months). Most of 

the patients presented with perianal discharge (97%), 

itching and discomfort (60%). Few patients presented with 

pain. On examination, external opening was found, 80% 

posteriorly, while 20% it was anteriorly. On digital rectal 



 

                           29 J I M D C   2 0 1 7  29 

examination internal opening was found, 61% at the 

dentate line and 39% above the dentate line. 

Majority of the patients (45 %) had transsphincteric 

complex fistula with secondary tract identified in 40% 

cases, 16 % cases with intra sphincteric, 36% cases with 

extra sphincteric, 3% cases with horseshoe shaped and 

5% with a combination of two. In 45 % of the cases, 

excision of primary and secondary tracts were done with 

loose seton placement while preserving the sphincter 

complex. A total of 21 patients of over series with 

recurrent disease, 90% of recurrent fistula were tertiary 

referrals from other hospitals and the nature of any 

previous fistula surgery was, therefore, difficult to 

ascertain (see table 1 for details of the patients).  

 

We also tried to find out the total number of operations, 27 

patients operated one time, 29 patients operated twice, 

while 8 patients were operated more than two times, 

though one of our patient was operated 9 times. About 

45% of our patients were operated by stage fistulectomy; 

that is excision of the lower fistula tract and placement of 

the Seton, followed by daily dressing and digitations of 

the wound. We came across bleeding in six patients, in 

which four were managed by pressure dressing and two 

were explored under anesthesia and bleeding was 

controlled. In our series the transient flatus incontinence 

was the commonest (12.3%) complication which got 

settled with passage of time. Recurrence of disease was 

found in 7 patients, out of them 2 were re-operated and 

found to have low fistula-in-ano, while 5 patients were not 

operated at the time of data collection and were at waiting 

list.  

D i s c u s s i o n  

Surgical treatment of FIA should aim at the complete 

elimination of the fistula while maintaining sphincter 

muscle function as much as possible.8 The criteria of 

determining success or failure of surgery are the 

incidence of recurrence or incontinence.9 In this trial a 

total of 65 patients were treated for complex fistula. Mean 

age of the patients was 45.3 ± 9.3, while in study of 54 

cases, Khalid et-al observed a high incidence in 3rd and 

4th decades.10 In a study of 85 cases, Takayuki et-al found 

that mean age incidence was 42.5 years which is 

comparable to that observed in our study. In this study 

there were 58 male and 7 female patients, with male to 

female ratio of 9:1. A similar ratio was reported by Saif et-

al, in their study, 41 males and 4 females underwent the 

process.12 In another study conducted by Buchanan et al. 

it was found that 17 males and 3 females were having the 

problem.13 These results show that male are 

approximately 9-10 folds at high risk of developing the 

condition compared to females. This proves male 

predilection because males have more intramuscular 

gland than female and they are more ramifying and more 

cystic. 

Most common symptom was perianal discharge 97 % 

followed by itching and discomfort 60%. Pain, bleeding 

P/R, and altered bowel habits were other presentations in 

some patients. Mean duration of symptoms before 

surgery was 11.5 months (range 1 to 60 months). Khalid 

and Takayuki et al reported that mean duration of 

symptoms before surgery was 18 months and 11 months 

respectively which is nearly comparable to mean duration 

of symptoms in our study.10,11 In current study 21 

(32.30%) patients were found previously operated for FIA, 

90% of recurrent fistula were tertiary referrals from other 

hospitals. G.N Buchanan et al reported in their study that 

19 patients out of 20, had previously undergone fistula 

surgery.13 In another study, 29 patients (64 %) out of 45, 

had previously undergone fistula surgery.12 

In this study, in majority of cases the fistula was found 

posteriorly (80 %). In another study of 199 cases, external 

opening of fistula were found posteriorly observed by 

Sainio and Husa.14 In this case series, majority of the 

Table 1. Findings and Management of patients of 
Fistula-in Ano (n 65) 

Characteristics N (%) 

Male        58 (89) 

Female    07 (11) 

Post. Ext opening  52 (80) 

Ant. Ext opening  13 (20) 

Sec. Tract Involvement 26 (40) 

Intra sphincteric 10 (16) 

Extra sphincteric 23 (36) 

Horseshoe shaped  02 (3) 

Combination 03 (5) 

Patient operated Once 27 (42) 

Patient operated Twice 29 (45) 

Patient operated more than Twice 09 (13) 



 

                           30 J I M D C   2 0 1 7  30 

patients (45%) had transsphincteric complex fistula with 

secondary tract identified in 40% cases, 16 % cases with 

intra sphincteric, 36% cases with extra sphincteric, 3% 

case with horseshoe shaped and 5% with a combination 

of two. While in the study of 160 patients, Vasilevsky et-al 

reported 41% cases of inter sphinteric,52 trans sphincteric 

and 1.3 % suprasphincteric.15 Some surgeons use a 

seton to drain FIA, whereas others believe that seton 

placement stimulates fibrosis and therefore promotes 

healing.16,17 When a seton is used to mark the primary 

track the subsequent decision whether or not to lay it 

open, can be made easier by palpating the seton in 

relation to the anal sphincter complex.16 Chemical seton 

placement may cause more pain than fistulotomy, and 

there is little difference in functional outcome between the 

two methods.18 Use of a cutting seton is also effective, but 

this too may cause minor disturbance of continence and 

may necessitate tightening. About 45% of our patients 

were operated by stage fistulectomy; that is excision of 

the lower fistula tract and placement of the Seton followed 

by daily dressing and digitations of the wound. However, 

in 36% cases, fistulectomy was performed. In 9% cases, 

fistulotomy was done. While 4% of patients were dealt 

with excision of the fistula tract and sphincteric repair, and 

colostomy done in one patient. We come across the 

bleeding in six patients (9.2%), in which four were 

managed by pressure dressing and two were explored 

under anaesthesia and bleeding was controlled.  

In our study, transient flatus incontinence was the 

commonest complication seen in 12.3% cases and it got 

settled with the passage of time. In another study 

conducted by Takayuki et al, incontinence was found in 

20.3% of their cases.11 Recurrence of disease was found 

in 7 patients out of them 2 were re-operated and were 

found to have low FIA while 5 still unoperated.  

C o n c l u s i o n  

The majority of complex FIA patients were treated by 

fistulotomy and staged seton fistulotomy with a low 

recurrence rate and low morbidity. 

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systematic review. Colorectal Disease. 2008;10(5):420-30. 

2. Song KH. New techniques for treating an anal fistula. Journal 
of the Korean Society of Coloproctology. 2012;28(1):7-12. 

3. Ortiz H, Marzo J, Ciga M, Oteiza F, Armendáriz P, De Miguel 
M. Randomized clinical trial of anal fistula plug versus 
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4. Chowdri NA, Parray FQ, editors. Benign Anorectal Disorders: 
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5. Cadeddu F, Salis F, Lisi G, Ciangola I, Milito G. Complex anal 
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6. Davies M, Harris D, Lohana P, Sekaran TC, Morgan A, 
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7. Sygut A, Zajdel R, Kędzia‐Budziewska R, Trzciński R, Dziki 
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8. Toyonaga T, Matsushima M, Tanaka Y, Suzuki K, Sogawa N, 
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9. Murugesan J, Mor I, Fulham S, Hitos K. Systematic review of 
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