I

“MAGNETIC RESONANCE IMAGING EVALUATION OF

PERIANAL FISTULAS”

BY

Dr. RASHMI ARAVIND PATELRM.B.B.S

Dissertation Submitted to theRajiv Gandhi University of Health Sciences, Bengaluru, Karnataka.

In partial fulfilment of the requirements for the Degree

DOCTOR OF MEDICINEIN

RADIODIAGNOSIS

Under the guidance ofDr. RAJKUMAR. S. YM.D,DNB, FRCR(UK)

ASSOCIATE PROFESSOR

DEPARTMENT OF RADIODIAGNOSIS,SSIMS & RC, DAVANGERE,

KARNATAKA,2018.

ABBREVIATIONS

CT-Computed TomographyFID- Free Induction Decay

MRI-Magnetic Resonance ImagingNMR -Nuclear Magnetic Resonance; RF-

Radiofrequency;

SNR -Signal-To-NoiseRatio;TR –Repetition Time

VII

LISTOFTABLES

TableNo. Table PageNo.

1 AGE 33

2 GENDER 34

3 SWELLING 35

4 DISCHARGE 36

5 NUMBER OFEXTERNALOPENINGS 37

6 INTERSPHINCTERICFISTULOUSTRACT MRI 38

7 HORSE SHOE SHAPED RAMIFICATION MRI 39

8 TRANSPHINCTERIC TRACTMRI 40

9 INTERNALOPENING MRI 41

10 EXTERNALOPENING 42

11 NUMBER OF INTERNALFISTULATRACTS 43

12 ST.JAMES'SUNIVERSITYHOSPITALCLASSIFICATIONTYPE 44

13 SUPRA LEVATOREXTENSION 45

VIII

LIST OF FIGURES

TableN

FiguresPageNo.

1 NORMALMRI ANATOMYOFTHE ANALREGION 10

2 ANATOMYOFTHE ANALREGION 8

3 NORMALMRI ANATOMYOFTHE SPHINCTERS. 13

4 ST. JAMESUNIVERSITY

HOSPITALCLASSIFICATIONFOR MRI

15

5 TYPEOF FISTULA IN RELATION TO ANATOMY 17

6 THE PARKSCLASSIFICATION 19

7 EXTERNALOPENINGOF FISTULA 20

8 TREATMENT OPTIONS OF FISTULA 23

IX

LIST OF GRAPHS

Table No.

GRAPHS PageNo.

1 AGE 33

2 GENDER 34

3 SWELLING 35

4 DISCHARGE 36

5 NUMBER OFEXTERNALOPENINGS 37

6 INTERSPHINCTERICFISTULOUS TRACTMRI 38

7 HORSE SHOE SHAPED RAMIFICATION MRI 39

8 TRANSPHINCTERIC TRACTMRI 40

9 INTERNALOPENINGMRI 41

10 EXTERNALOPENING 42

11 NUMBEROFINTERNALFISTULATRACTS 43

12 ST. JAMES'SUNIVERSITYHOSPITALCLASSIFICATIONTYPE 44

13 SUPRA LEVATOREXTENSION 45

X

LIST OFIMAGES

IMAGENo IMAGE

PageNo.

1 EXTERNALOPENINGOFANALFISTULA 65

2 PROBE TEST 65

3 FISTULECTOMYPROCEDURE 65

4 T2 AXIALIMAGE-

INTERSPHINTERICFISTULAONTHE LEFT

66

5 CORONALIMAGESHOWINGINTERSPHINCTERICFI

STULAWITH AMEDIALRAMIFICATION

TOTHERIGHT SIDE

66

6 T2 AXIAL IMAGE SHOWING

FISTULA IN THEINTERSPHINCTERIC

66

7 T2 AXIAL IMAGE SHOWING

FISTULA IN THEINTERSPHINCTERIC

67

8 T2 CORONAL IMAGE SHOWING

RIGHTEXTRASPHINTERIC FISTULA

67

9 T2 SPAIR IMAGE SHOWINGMEDIALRAMIFICATIONOFTHE RIGHTPERIANALFISTULA

67

10 T2 CORONALIMAGESHOWING

TRANSPHINTERICFISTULA WITH

68

11 T2CORONALIMAGESHOWING

PARARECTALCOLLECTIONABOVETHESUPRALEV

ATORPLANEON THE LEFT

68

XI

12 T2 CORONAL IMAGE SHOWING A BLIND ENDING

LATERAL RAMIFICATION OF THE FISTULA ON

THE LEFT SIDE

68

13 T2 CORONAL

IMAGEINTERSPHINCTE

SHOWING RIGHT

69

XII

ABSTRACT

Perianal fistulization is an uncommon but important condition of the gastrointestinal

tract that causes substantial morbidity. Perianal fistulas occur in approximately 10 of

100,000 persons, with a twofold to fourfold male predominance. Although anal

fistulas were known to Hippocrates and have been described throughout the centuries,

they began to receive special attention in the 19th century. In 1835, Frederick Salmon

founded the Benevolent Dispensary for the Relief of the Poor Afflicted with Fistula,

Piles, and Other Diseases of the Rectum and Lower Intestines—the now world famous

St Mark’s Hospital—in London. Much of our understanding of perianal fistulas comes

from the work of surgeons at St Mark’s Hospital: Salmon, who operated on Charles

Dickens; Goodsall, who described the course of fistulous tracks from the skin to the

anus ; and Parks, whose classification of fistulas in relation to anal anatomy is widely

used in surgical practice .Complex perianal disease is an extremely debilitating

condition for the patient which leads to significant impingement on quality of life. The

accurate identification of anatomical areas of involvement and subsequent appropriate

management is crucial to achieving a successful outcome when treating anal fistulae.

Magnetic resonance imaging (MRI) has become a powerful tool in the evaluation of

anal anatomy. In patients with complex disease MRI is an important adjunct in

delineating disease location and extent, its relationship to sphincter muscles, and in

planning management. Knowledge of pelvic anatomy and associated disease processes

is essential to radiologists and surgeons involved in the management of anorectal

fistulae.On going technological advances continue to contribute to significant

improvements in the images obtained during MR imaging. MRI allows the

classification of fistulous tracts and the identification of underlying infection. It directs

XIV

the ensuing surgical management reducing the incidence of recurrent disease. This

may result in the need for repeated anorectal surgeries with the attendant risk for

incontinence. The purpose of the study is to evaluate the role of Magnetic Resonance

Imaging in Accurately detecting and classification of perianal fistulae

KEY WORDS : Perianal fistulization, Perianal fistulas, St Mark's hospital, Goodsall,

Park's, Magnetic Resonance Imaging

XV

INTRODUCTION

Anal fistula is a common peri-anal surgical problem with which the patient

presents the clinician. A fistula-in-ano is an abnormal hollow tract or cavity that

is lined with granulation tissue and that connects a primary opening inside the

anal canal to a secondary opening in the perianal skin. It is a common peri-anal

surgical problem with which the patient presents the clinician. In around ninety

percent of cases the perianal fistulas are as aresult of secondary to impaired

drainage of the anal glands, according to the “cryptoglandular hypothesis”1

As such, the vast majority of these infections are acute and significant

majority is a contributory to chronic, low-grade infections.2

Infection and anal gland drainage obstruction may lead to an acute

perianal abscess. Some abscesses may resolve spontaneously via internal

drainage into the anal canal, whereas others may require surgical incision and

drainage 3-5 Abscesses that are inadequately or incompletely drained will persist

and may ultimately seek additional drainage pathways through the intersphincteric

space or across the sphincter complex and, in the process, create fistulous tracts.

3-5

Most of these anal fistulae are easy to diagnose with a good source of

light, a proctoscope and digital rectal examination. Despite this establishing a

complete cure of these anal fistulae is very problematic for these two reasons.

First cause being the affection of the disease with respect to the site. Secondly,

the significant percentage of these diseases persists or

~ 1 ~

resumes when the correct type of surgery is not adopted or when

postoperative care is insufficient, or intra-operative if the extensions are lost or

unnoticed.2,3

Also anal fistula needs to differentiated from the following processes,

which do not communicate with the anal canal like the hidradenitis

suppurative, infected inclusion cysts

,pilonidal disease, bartholin gland abscess in females5-7.

The state of the spectrum requires the importance of finding the most

common cause and therefore9-11 a better understanding of the targeted and

specialized management of the condition. In today's scenario where time is money

and litigation is a recalling rule. Better handling of a fistula would be through the

images to see the possible pathways and the branching followed by definitive

surgery.

MR Fistula is the best imaging mode when it comes to soft tissue, especially

the perianal region because it can help identify the presence of abscesses and

extensions that would otherwise be lost during surgery and thus prevent

recurrences.12-15

In view of the above said we did a study “MAGNETIC RESONANCE

IMAGING EVALUATION OF PERIANAL FISTULAS” with the aim to

correlate the MRI findings with clinical examination and classify them.

~ 2 ~

OBJECTIVES

1. The aim and objectives of the present study were as follows:-

2. To Describe and classify perianal fistulae on MRI

3. To determine the MRI sequence most efficient to determine the type of

perianal fistulae and to identify the internal opening.

4. To correlate the MRI findings with clinical examination.

5. To correlate the MRI findings with surgical findings and hence accuracy of

MRI in evaluation of perianal fistulae.

~ 3 ~

REVIEW LITERATURE

Historical aspects of the anorectal fistulas

Anorectal fistulas have been a disease of fascination even in the past ,history

dates back to though era of Hippocrates who used horsehair as a seton to treat

anal fistulas .16

In 1376, the English surgeon John Arderne is said to have written a treatises on

perinal diseases in which he has described fistulotomy and seton use. 17

These diseases affected everyone equally even the great Louis XIV emperor of the

18th century was not spared.18

The late 19th and early 20th centuries saw advances in the theories of perinal

fistulas and the treatment of perinal fistulas with contributions of the renowned

scholars like Goodsall and Miles, Milligan and Morgan, Thompson, and

Lockhart-Mummery, and 1976, Park who refined the classification system of the

disease.19

EPIDEMIOLOGY

Sainio et al in their study that was spread over a ten year old period stated that

anal fistulas affected 510,000 people, 20 The mean incidence of fistulas per

100,000 of the general population was established at 8.6, i.e. 12.3% for males, and

5.6% for females.

~ 4 ~

Nelson et al. found in their meta-analysis that 20,000–25,000 fistulas were treated

annually in the USA21Anal fistula has its maximum incidence between the third

and fifth decades. Men are affected two to four times more commonly 22 and in

the study, all the patients younger than 15 years of age were male 21

MRI TECHNIQUE22,23

Magnetic resonance spectroscopy allows the non-invasive measurement of

selected biological compounds in vivo .Feasibility was first demonstrated in

humans in the mid-1980s. Since that time, much experience has been

accumulated with the use of Magnetic resonance spectroscopy in both research

and clinical applications. Proton spectroscopy has been recognized as a safe and

noninvasive diagnostic method that, coupled with magnetic resonance imaging

techniques, allows for the correlation of anatomical and physiological changes in

the body.

Pre-processing24

An MR signal has to go through a number of pre-processing steps in order

to be usable. Most of those steps increase the quality of the final spectrum and

others take into account some of the technicalities of the acquisition.

Apodization is a process that consists in convolving the free induction decay with

a decreasing exponential. It emphasizes the initial part of the signal, where the

signal-to-noise ratio is high and minimizes the end part, where the decay is

substantial. Doing this increases the quality of the resulting spectrum but at the

expense of enlarging the width of the peaks24

~ 5 ~

MRI has a high intrinsic contrast resolution with an excellent demonstration of the

anal sphincter

and pelvic floor anatomy as well as identification of tracts and abscesses.The

technique has established itself as a reliable technique for the imaging of

perianal fistula25,26 T2-weighted sequences and a fat suppressed sequence are

mainstay. A gadolinium enhanced T1-weighted sequence is very helpful for

differentiating between fluid and granulation tissue, important in abscesses .First,

a sequence in the sagittal plane is performed. The transverse and coronal

sequences must be aligned with the anal canal at the sagittal sequence.

~ 6 ~

There are two types of coils that can be used, the endoanal coil and phased-array

external coils. The latter is far more widely available and most experience concerns

this coil. Advantage of the endoanal coil is the higher spatial resolution, which

might be beneficial in identifying small tracts and internal openings pecially in

patients with Crohn’s disease26 and the wide availability. When both coils are

available an approach where endoluminal magnetic resonance imaging is used for

cryptoglandular fistulas and external MRI in Crohn’s disease seems optimal.

ANATOMY

Knowledge of the anatomy of the anal sphincter complex and surrounding spaces

is crucial for image interpretation The anal canal extends from the levator ani

muscle cranially to the anal verge caudally and is surrounded by the internal

and external anal sphincters. The internal sphincter is the inferior extension of

the inner circular smooth muscle of the rectum and is primarily responsible for

resting involuntary anal continence27

The external sphincter is composed of striated skeletal muscle, which is contiguous

with both the

levator ani and puborectalis muscles superiorly and is primarily responsible for

voluntary continence. As such, injury to the external sphincter during surgery

can lead to fecal incontinence. The internal and external sphincters are separated

by the intersphincteric.28-30

~ 7 ~

FIGURE 1: ANATOMY OF THE ANAL REGION

~ 8 ~

NORMAL MRI ANATOMY OF THE ANAL SPHINCTER

The function of the anal canal and associated anatomy is to maintain fecal

continence. A basic understanding of the anatomy of the anorectal mechanism is

useful to appreciate the common pathways of disease spread in perianal fistula.

The anal canal represents the terminus of the large intestine and measures

between 2.5 to 5 centimeters in length. Two muscular complexes, the internal

and external sphincters, act in concert to provide the contractile effort needed for

fecal continence, with the internal sphincter providing the majority of the resting

tone. The internal sphincter is essentially a continuation of the circular muscular

wall of the rectum, while the external sphincter is functionally connected via the

puborectalis muscle to the levator ani, which forms much of the muscular pelvic

floor . The interstitial tissue between the two sphincters provides a pathway for the

circumferential and axial spread of disease . Penetration of both sphincters

allows disease to enter the fat filled ischioanal fossa, while violation of the

levator plate permits access between the superficial ischioanal fossa and pelvic

pararectal space .31-32

~ 9 ~

FIGURE 2: NORMAL MRI ANATOMY OF THE ANAL REGION 33

The anal sphincter is composed of several cylindric layers . The innermost layer is

the subepithelium. The next layer is the cylindric internal anal sphincter .which is

relatively hyperintense on magnetic resonance imaging. The hypointense

fibroelastic longitudinal muscle courses through the fat-containing inter-

sphincteric space. The outermost layer is composed of relative hypointense

striated muscle with the external anal sphincter inferiorly and the puborectal muscle

superiorly . The puborectal muscle is part of the levator ani muscle, which also

includes the levator plate .33,34

~ 10 ~

Anal Sphincter Defects and Scar Tissue

An anal sphincter defect commonly is defined as a discontinuity of the muscle

ring or an anatomic defect or is recognized by a hypo-intense deformation on MRI

of the normal pattern of the muscle layer due to replacement of muscle cells by

fibrous tissue (functional defect, scar tissue) With magnetic resonance imaging, it

is possible to distinguish an anal sphincter defect from scarring Although there

are differences in diagnosing a defect from scar tissue, the clinical consequences do

not differ.35

Atrophy of the external anal sphincter is characterized by severe thinning of the

muscle fibers or replacement of muscle fibers by fat.36

MRI Features of fistula

On MR images the difference between fibrosis and active fistula tracts can be

easily made. On T2-weighted images, active fistulas and abscesses, which are

filled with pus and debris, are hyperintense, whereas fibrosis is hypointense.

Also the difference between fluid within a tract (e.g. abscess) and active

inflammation can be seen. On post contrast T1-weighted images fluid is

hypointensewhile granulation tissue enhances leading to high signal intensity. The

external anal sphincter has a relatively hypointense aspect and contrasts very well

with the fat in the ischioanal fossa as well as the intersphincteric space on T2-

weighted images. 37

In complex fistulas and high fistulas, magnetic resonance imaging can therefore be

considered as primary imaging technique in patients suspected for these fistulas.

~ 11 ~

When endoscopic ultrasound is used as initial imaging technique in such

patients, magnetic resonance imaging should be performed when endoscopic

ultrasound in inconclusive (e.g. Cases where the fistula cannot be followed

proximal with endoscopic ultrasound). Magnetic resonance imaging with an

external coil does not need introduction of an endoanal device and patient comfort is

in this respect better than for endoscopic ultrasound and endoanal magnetic

resonance imaging.38

For a broad anatomic overview, unenhanced T1 weighted images are ideal for

anatomically delineating the sphincter complex, levator plate, and ischiorectal fossa.

For evaluation of fistulous tracts, T2 weighted images demonstrate hyperintense

fluid within the tract as contrasted to the hypointense fibrous wall of the

fistula. T2 weighted images help differentiate the boundaries between internal

and external sphincters because sphincters and muscles have low signal

intensity while active tracks and extensions have high signal intensity. On

gadolinium-enhanced fat suppressed T1 weighted images, fistulous tracts and

active granulation tissue demonstrate intense enhancement while any fluid

in the track is hypointense.39-42

Chronic fistulous tracts or scars demonstrate low signal intensity on both T1 and

T2 weighted images. There is lack of early enhancement of chronic fistulous

tracts and scars on gadolinium enhancement images. Abscesses can demonstrate

high T2 signal due to the presence of pus in the central cavity.

~ 12 ~

On contrast enhanced fat suppressed T1 weighted images, abscesses demonstrate

low signal intensity centrally with ring enhancement. On postoperative magnetic

resonance imaging, T1 weighted images demonstrate high signal intensity of

hemorrhage products and can thereby help differentiate hemorrhage from residual

tracks .41-44

FIGURE 3: NORMAL MRI ANATOMY OF THE SPHINCTERS.

~ 13 ~

THE ANATOMICAL PARTS OF THE FISTULA45

A complete fistula has four features of interest, that is

(1) the external opening,

(2) the internal opening,

(3) the main track,

(4) branches or main track extensions.

Goodsall 45 suggested a rule that is not infallible but is of definite help in

ascertaining where to search first for the primary opening. He stated: "All fistulae

with their internal openings behind a line drawn transversely through the center of

the anal, have their internal openings in the middle line behind; and that in cases

in which the external aperture is anterior to this line, the inner opening is

directly opposite the external one.

St. James University hospital classification for MRI. 46

Grade Fistula type

1 Simple linear intersphincteric fistula. The fistulous tract extends from the

skin to the anal canal. There is no ramification within the sphincter complex.

The tract is confined by the external sphincter

2 Intersphincteric fistula with abscess or secondary tract. The fistula is

bounded by the external sphincter. Secondary tracts may be of horseshoe type or

may ramify in the ipsilateral intersphincteric plane.

3 Trans-sphincteric fistula. The fistula pierces through both layers of the

sphincter complex and then arcs down to the skin through the ischioanal fossa.

4 Trans-sphincteric fistula with abscess or secondary tract within the

~ 14 ~

ischioanal fossa. The abscess manifests as an expansion along the primary tract or

in the ischioanal fossa.

5 Supralevator and translevator disease. The fistula extends above the

insertion of the levatorani muscle. A suprasphincteric fistula extends upward in

the intersphincteric plane and over the top of the levatorani muscle to pierce

downward to the ischioanal fossa. Extrasphincteric fistulas reflect extension of

primary pelvic disease down through the levator plate.

FIGURE 4: ST. JAMES UNIVERSITY HOSPITAL CLASSIFICATION FOR

MRI

~ 15 ~

Based on etiology

The following classification reasons are listed in order most frequently:

1. Trauma. External traumas are 10, rarer (2% of cases) and are generally as

well of the result of Fall on an object that can tear or hurt the lower intestine

mucosa, or it may be the result of neglected use of the colon probe end or

enema. perforation of the anorectum from impacted chicken or fish bones, from

externally penetrating trauma (stab or gunshot wounds), 47

The internal source is discussed in factors acting on the cryptic condition.48

2. The possibility of trauma to the rectum can occur during the abdominal

surgeries, especially where pelvic adherence is present. In the past was seen

during the procedures like, pubic prostatectomy one procedure rarely done now .49

3. Other causes of iatrogenic fistulas can occur when hemorrhoidal treatment

by injection of sclerosant is done in the wrong plane and necrosis occurs, these

are considered an the ideal conditions for the formation of blind and fistulas.50

4. Rare tumors are often not site ulcerations and therefore must be considered

as an etiologic factor.51

5. Tuberculosis is another common etiologic factor52

Based On the Position50

Fistulae which are purely anal or rectal are of several varieties and may be

named from their shape and number of openings as follows:

"Complete, · which has an opening into the skin and one into the rectum or

anus.

~ 16 ~

o This may be a simple, straight or slightly tortuous tract,

o complex affair with many communication sinuses, which may have blind

endings or rather elaborate communication passages situated in the subcutaneous

tissue and extend over to the opposite side of the anus.

A blind-internal,· fistula which has an opening into the bowel but no opening on the

skin."complete internal,· fistula which has both of its openings in the bowel.

Fourth, the -horse-shoe shape· or ·complete external- which has both of its

openings in the skin.

Fifth, Colt includes the blind-external" which has a communication with the

skin but none with the bowel.

FIGURE 5 :TYPE OF FISTULA IN RELATION TO ANATOMY

~ 17 ~

The classification system developed by Parks, Gordon, and Hardcastle (generally

known as the Parks classification) is the one most commonly used for fistula-

in-ano. This system (see the image below) defines four types of fistula-in-ano

that result from cryptoglandular infections, as follows 51:

The Parks classification, although adapted to some extent, is still the most widely

used classification of perianal fistulas. This classification was primarily developed

for surgical treatment and is therefore especially important for patients treated

surgically. Principal finding in classification is the course of the tract from the anal

mucosa to the perineal skin, in relation to the most outer, striated muscle layer .

Intersphincteric fistulas (24% of cases of primary cryptoglandular fistulas)

course from the internal opening in the anal canal through the internal sphincter and

the intersphincteric plane to the perineal skin.

A transsphincteric fistula (58%) is a fistula that - in addition to the tract as

described for an intersphincteric fistula - passes from the intersphincteric plane at

varying levels through the

~ 18 ~

outer striated muscle layer (thus external sphincter or puborectal muscle) into

the ischioanal fossa.

Relative rare are extrasphincteric fistulas (less than 1%) where the tract

passes from the perineal skin through the ischioanal fat and the levator plate to

the internal opening in the rectum.

Submucosal fistulas (15%) are not included in the original publication of

fistula classification by Parks as these fistulas where not encountered at that tertiary

referral center.

FIGURE 6 :THE PARKS CLASSIFICATION

~ 19 ~

SYMPTOMATOLOGY 1,-5, 28

The patient first complains of an itching or uncomfortable feeling in the region of

the anus which gradually increases and later develops into a severe throbbing pain.

The area about the buttocks becomes quite painful. 47,50 All of these signs and

symptoms are more or less completely relieved and disappear with the rupture of the

skin and discharging of considerable serosanginous fluid or the discharge through

the rectum47,50 As long as free drainage continues the patient will be

symptom free with the exception of local irritation and some slight discomfort. As

soon as the drainage stops the symptoms will in most cases begin to return

although some may go for months or years without recurrence of symptoms.

47,50

FIGURE 6: EXTERNAL OPENING OF FISTULA DIAGNOSIS 47

The diagnosis of fistulae can usually be made from the history and local observation.

It is usually a easy matter, especially when the fistula is complete.

~ 20 ~

INVESTIGATIONS

Classifications are important because treatment differs between different types of

tracts. Simple submucosal, intersphincteric and also low (1/3 lower part of the

anal sphincter) transsphincteric tracts can be treated with fistulotomy without a

(substantial) impact on continence.

IMAGING TECHNIQUES FISTULOGRAPHY AND CT

Both fistulography and computed tomography scan are now considered obsolete

techniques. Few studies have been performed testing the accuracy of

fistulographyand computed tomography scan, all with disappointing results.

Sensitivity of fistulography is in the study of Weismann et 49

88% and the specificity 100%. The sensitivity of 88% can be explained because in

fistulography, possible extensions might not fill with contrast because of debris

or granulation tissue and the anatomical relations are not visualized because pelvic

floor muscles are not identified. In computed tomography scan, the lack of contrast

resolution prohibits differentiating fistulas from pelvic floor muscles.

Endoanal ultrasound

Endoscopic ultrasound gives a detailed visualization of the anal sphincter

complex50-51. Endoscopic ultrasound is a simple and fast technique and generally

well tolerated by patients. A rotating probe covered with a hard sonolucent cone

filled with water, with a 360º radius and a frequency between 5 and 16 MHz is

introduced in the rectum with the patient lying on the left side or supine position

for women. The probe is then slowly withdrawn so that the sphincter complex

~ 21 ~

can be visualized. On a normal ultrasound, the internal sphincter, intersphincteric

space and external sphincter are visible as concentric circular layers. The internal

sphincter is hypoechoic and 2-3 mm in width.

With three-dimensional endoscopic ultrasound a three-dimensional volume is

obtained which can be used to reconstruct in the coronal and sagittal planes,

which is helpful in identifying the extent of the fistula and the relationship to

surrounding structures. West et al compared in 21 patients with a cryptoglandular

fistula hydrogen peroxide enhanced ultrasound with three- dimensional

reconstruction with endoanal MRI and surgery. Endoscopic ultrasound had an

agreement of 81% with surgery and endoanal MRI and surgery 90%. To our

knowledge, this is the only study that prospectively compared52 hydrogen

peroxide enhanced ultrasound with MRI with a surgical reference standard.

TREATMENT 47,50

The only accepted treatment for fistula today is surgery. The principle underlying

this treatment is to lay the main track open together with all offshoots extending

from it. Then allow the wound to heal by granulation from the bottom and not

permit the epithelium to bridge over until the granulations have grown from the

deepest point of the wound to the surface

The goals in the treatment of an anal fistula are to eliminate the primary fistula

opening, any associated tracts, and any secondary openings without a change in

continence. Most anal fistulae are simple and can be treated using a

~ 22 ~

fistulotomy, which has a low recurrence rate and an acceptable rate of

morbidity. eton for treatment of perianal fistula can be of the cutting or a loose

type. Advancement flap is still considered to be the gold standard of treatment

for a complex anal fistula

FIGURE 7: TREATMENT OPTIONS OF FISTULA

~ 23 ~

LITERATURE SURVEY ON MRI IN PERIANAL FISTULA

Lunniss et al. reported a concordance rate of 86-88% between MRI and surgical

findings T2W images (TSE and fat-suppressed) provide good contrast between

the hyperintense fluid in the tract and the hypointense fibrous wall of the

fistula, while providing good delineation of the layers of the anal sphincter.53

Pushpinder S Khera et al of the 43 patients in our study, eight (18%) were identified

as having a perianal sinus only, with no fistula extending into the anal canal. The

rest of the 35 cases were evaluated for the site of the primary tract and its

ramifications, the presence/absence of external sphincter involvement, and the

location of the internal openings. Three patients had a primary or recurrent perianal

fistula with associated Crohn's disease.Two of these three cases had multiple

fistulae and all three had abscess formation .Of the remaining 32 patients

without Crohn's disease, 24 had a primary fistula and, of these, seven had

previously undergone perianal abscess drainage. Eight patients had undergone

previous fistula surgery and had presented with a recurrence. Out of a total of 44

fistulae in these 35 patients, 14 (33%) were transsphincteric,25 (60%) were

intersphincteric. and three (7%) were extrasphincteric.No suprasphincteric fistula

was encountered in the study. Twenty-seven fistulae (61%) were simple,

whereas 17 (39%) showed complications (abscess formation, branching course,

inflammatory tissue, 54.

Dariusz Waniczek et al evaluated MRI fistulography findings were analyzed and

compared with intraoperative conditions in 14 patients (11 men and 3 women)

diagnosed in the years 2005– 2009. Eight patients had recurrent fistulas and 6

~ 24 ~

had primary fistulas. Imaging was performed with a GE SIGNA LX HS scanner

with a 1.5-Tesla field strength and a dedicated surface coil placed at the level of

hip joints. Contrast agent was a gadolinium-based solution. Intraoperative findings

were consistent with radiological descriptions of 13 MRI fistulographies. Only in

one case, according to surgery findings, it was a transsphincteric fistula with

an abscess in the ischioanal fossa, with an orifice in the posterior crypt; the

radiologist described it as a transsphincteric, internal blind fistula.54

Buchanan et al. 55 in their study showed that MR increases the accuracy of

diagnosis by 10% in comparison to EAUS. Additionally, there was a threefold

decrease in recurrence rate after surgical interventions based on appropriate

diagnostics with the use of MR only.

Maier et al. 56showed a statistically higher efficiency in the detection of

perianal fistulas and abscesses in 39 patients with the use of magnetic resonance

(84% sensitivity) as compared to endosonography (60% sensitivity). False-positive

results were present in 6 patients (15%) examined with MR and in 10 (26%)

examined with endosonography.

Beets-Tan et al57 assessed the usefulness of the method by comparing the

results of MRI in patients before surgery with intraoperative findings. They

proved that its sensitivity and specificity for fistulous canal detection amounted to

100% and 86%, respectively. For a horseshoe fistula this was 100% and 100%, and

for internal openings – 96% and 90%.

Mullen et al. 58 showed retrospective analysis of all patients with Anorectal

fistulas with MRI assessment on 40 patients with primary pathologies like

~ 25 ~

perianal sepsis in 20 (50%), Crohn’s disease in 11 (27.5%), primary Anorectal

fistulas in 6 (15%) and others in 3 (7.5%) patients found that MRI established

the fistula anatomy and guided further surgery in 47.1%, correlated with EUA

findings in 38.2% and excluded a suspected fistula in 14.7% of these.

Uttam George 59concluded that MRI exquisitely depicts the perianal anatomy

and shows the fistulous tracks and their associated ramifications and abscesses.

It thus provides an excellent preoperative understanding of the disease, enabling

selection of the most appropriate surgical treatment and therefore minimizing all

chances of recurrence.

60 assessed the contribution of various magnetic resonance

imaging (MRI) sequences in determining the type of perianal fistula and in

obtaining critical information for surgical decisions, as well as to define the optimal

combination of sequences for readers with varying levels of experience , which

included 33 MRI examinations in 26 patients with suspected perianal fistula.

And found that for all sequences, there was statistically significant agreement

between readers for fistula classification, internal opening location, and the

presence of sinus tracts, abscess, a horseshoe component, and inflammation.

O Mailley et al41 stated that Adequate understanding of relevant pelvic

anatomy and fistula classification on MRI examinations is essential in providing

proper assessment of perianal fistulas. Evaluation of clinically undetectable disease

has a significant bearing on guiding medical and surgical therapy and can help

minimize recurrence and better predict outcome compared with surgical

exploration

~ 26 ~

Torkzad MR et al 61 stated in their study that they recommend a short period of

fasting (4 h) before imaging. Since most fistulas are located below the pelvic

floor, bowel peristalsis should not be a problem in the majority of cases.

However, in cases where there is suspicion of supralevator extension of the

disease, antiperistaltic agents might prove essential.

Rishi Philip Mathew et al 62at the of Radio-Diagnosis, Father Muller Medical

College found that The most common age group to be affected was the 4th

decade (30%). Out of the total 30 patients, 28 (93%) were males and 2 (7%) were

females. 23 patients had primary fistulas while 3 had undergone previous fistula

surgery and presented with recurrence. 19 patients (73%) had intersphincteric

fistula while 7 patients (27%) had transsphincteric fistula. 3 patients had perianal

abscesses with no evidence of fistula. There was one false positive and one false

negative case. As per our study MRI had a sensitivity and specificity of 96.15% and

75% respectively.

D. Schettini et al 63 their study concluded THAT MR is the best imaging technique

for evaluating perianal fistulas, because it provides an accurate assessment of the

anal canal, anal sphincter complex, and allows detection of any fistula.

~ 27 ~

Ryan B. O 64 in their study found that MRI evaluation of perianal fistulas can be

challenging, and knowledge of relevant pelvic anatomy and fistula classification

remains crucial in the diagnosis. MRI is highly accurate for fistula depiction and,

by providing an accurate assessment of disease status and extension can help

surgical planning to minimize recurrence and detect clinically unapparent

disease.

Naglaa Daabis 65 in their study found that MRI is a useful procedure for successful

management of peri-anal fistula by correct assessment of the extent of disease

and relationship to sphincter complex. Also it helps in identification of secondary

extensions, particularly horseshoe tracts and abscesses resulting in complete

evaluation and highest possible diagnostic accuracy aiding successful surgical

interventions, aiming to reduce complications and recurrences.

R. BaZ 66 in their study found that MRI has become the method of choice for

evaluating perianal

fistulae due to its ability to display the anatomy of the sphincter muscles

orthogonally, with good contrast resolution.

J A Spencer et al 67 in their study found that MR imaging correctly allowed our

blinded observers

to predict the surgical anatomy of perianal disease in 37 of the 42 patients

(accuracy, 88%). For detection of the presence and site of an enteric fistulous

~ 28 ~

entry, MR imaging had a sensitivity of 97%, a specificity of 67%, a positive

predictive value of 88%, and a negative predictive value of 89%.

Regina G. H. Beets-Tan et al68 in their study on fifty-six patients with anal

fistulas underwent high-spatial-resolution MR imaging MR imaging provided

important additional information in 12 (21%) of 56 patients. In patients with

Crohn’ disease, the benefit was 40% (six of 15); in patients with recurrent

fistulas, 24% (four of 17); and in patients with primary fistulas, 8% (two of 24).

The difference between patients with or without Crohn’s disease and between

patients with a simple fistula versus the rest was significant (P < .05). The

sensitivity and specificity for detecting fistula tracks were 100% and 86%,

respectively; abscesses, 96% and 97%, respectively; horseshoe fistulas, 100%

and 100%, respectively; and internal openings, 96% and 90%, respectively.

~ 29 ~

METHODOLOGY

SOURCE OF DATA :

The study was a prospective correlative study done on a of 30 patients who met

a predefined inclusion and exclusion criterion and underwent MRI examination of

patients for perianal fistula referred from Surgical departments at the SSIMS &

RC, Davangere. The study was done over a period of 2 years from October 2015 to

September 2017.

INCLUSION CRITERIA:

All patients aged 18 to 80 referred with clinically diagnosis of perianal fistula.

EXCLUSION CRITERIA:

MRI technically inadequate for assessment

Operative details not available.

Patients with prior history of surgery in the anorectal region are excluded.

METHOD OF COLLECTION OF DATA:

All pelvic MRI scans were done in 1.5 Tesla G.E MRI scanner in SSIMS & RC,

Davangere.

~ 30 ~

The following sequences were obtained in both the coronal and axial planes:

thin slice, high resolution T1-weighted (W) spin echo; T2-weighted turbo spin

echo; short tau inversion recovery (STIR); contrast enhanced T1-weighted

images and diffusion weighted images.

All patients underwent surgery as a primary treatment modality and

intraoperative details of the fistula were recorded.

MRI findings were compared with intraoperative records, which were

considered as gold standard in treatment.

Different sequences and their combination were analyzed for best

determination of the fistula.

~ 31 ~

SAMPLE SIZE OF ESTIMATION

The study was a prospective correlative study done on a of 30 patients who met

a predefined inclusion and exclusion criterion and underwent MRI examination of

patients for perianal fistula referred from Surgical departments at the SSIMS &

RC, Davangere. The study was done over a period of 2 years from October 2015 to

September 2017.

~ 32 ~

RESULTSDEMOGRAPHIC DATA

Age

Age Frequency Percent

0-25 5 14

26-35 16 46

36-45 6 17

46-55 5 14

56-60 2 6

>60years 1 3

35 100

TABLE 1 : AGE

GRAPH 1 : AGE

The mean age on the present study was 34(SD+) 2.3 years. The youngest case was

24 years and an elder was 62 years of age .most cases were in the age group 26-45

years.

Age 18 1614 12 10

8 6 4 2 0

16

56

5

2 1

0-25 26-35 36-45 46-55 56-60 >60years

~ 33 ~

GENDER

Gender Frequency Percent

Female 3 8.3

Male 32 91.7

Total 35 100.0

TABLE 2: GENDER

GRAPH 2: GENDER

In the present study we found that 32 cases 92 % were males as compared to 8 %

females were affected with fistula

GENDER

Female 8%

Male 92%

~ 34 ~

CLINICAL DETAILS

SWELLING Swelling Frequency Percent

No 28 80

Yes 7 20

Total 35 100.0

TABLE 3: SWELLING

GRAPH 3: SWELLING

In the present study and 7 cases were presented with swelling

60 Swelling

50

40

30

20

10

0 NO YES

~ 35 ~

40

35

30

25

20Yes

15

10

5

0

Frequency

DISCHARGE

DISCHARGE Frequency Percent

Yes 35 100.0

TABLE 4: DISCHARGE

DISCHARGE

GRAPH 4 :DISCHARGES

In the present study all 35 cases were presented with discharge

~ 36 ~

MRI FINDINGS

NUMBER OF EXTERNAL OPENINGS MRI

NUMBER OF EXTERNAL OPENINGS Frequency Percent

1 33 94

4 2 6

Total 35 100.0

TABLE 5: NUMBER OF EXTERNAL OPENINGS

GRAPH 5: NUMBER OF EXTERNAL OPENINGS

In the present study on evaluation of the MRI findings we found that in 33 cases

94% had a single opening.

NUMBER OF EXTERNAL OPENINGS 1 EXTERNAL OPENING, 33

35

30

25

20

15

10

50

4 EXTERNAL OPENING, 2

~ 37 ~

INTERSPHINCTERIC FISTULOUS TRACT MRI

Yes 30 60No 5 40Total 35 100

TABLE 6: INTERSPHINCTERIC FISTULOUS TRACT MRI

GRAPH 6: INTERSPHINCTERIC FISTULOUS TRACT MRI

In the present study on evaluation of the MRI findings we found that in 30 cases

Intersphincteric fistulous was seen .

INTERSPHINCTERIC

No 2

INTERSPHINCTERIC

Yes 33

0 5 10 15 20 25 30 35

~ 38 ~

HORSE SHOE SHAPED RAMIFICATION MRI

HORSE SHOE SHAPED RAMIFICATION PERCENT

No 33 91.7

Yes 2 8.3

Total 35 100.0

TABLE 7: HORSE SHOE SHAPED RAMIFICATION MRI

GRAPH 7: HORSE SHOE SHAPED RAMIFICATION MRI

In the present study on evaluation of the MRI findings we found that in 33 cases

Horse shoe shaped ramification was seen.

INTERSPHINCTERIC

No 2

INTERSPHINCTERIC

Yes 33

0 5 10 15 20 25 30 35

~ 39 ~

TRANSPHINCTERIC TRACT MRI

No 31 87Yes 4 13Total 35 100

TABLE 8: TRANSPHINCTERIC TRACT

GRAPH 8: TRANSPHINCTERIC TRACT

In the present study on evaluation of the MRI findings we found Transphincteric

tract in 31cases, 87%

TRANSPHINCTERIC TRACT

30

25

20

15

10 5 0

No, 31

Yes, 4

No Yes

~ 40 ~

Internal opening 15

10

4

2 1 1 1 1

INTERNAL OPENING MRI

INTERNAL OPENING FREQUENCY PERCENT

1 0 CLOCK 1 3

11 0 CLOCK 4 11

12 0 CLOCK 15 43

2 0 CLOCK 2 6

2,3 0 CLOCK 1 3

2,5,6 0 CLOCK 1 3

6,10,11,7 0 CLOCK 1 3

6 0 CLOCK 10 28

TABLE 9 : INTERNAL OPENING

GRAPH 9 : INTERNAL OPENING

In the present study on evaluation of the MRI findings the above table and graph

show the level of internal openings.

CLOC CLOC CLOC CLOC CLOC CLOCK 0 CLOCK

~ 41 ~

External opening MRI

SINGLE 34 97MULTIPLE 1 3

TABLE 10: EXTERNAL OPENING

GRAPH 10: EXTERNAL OPENING

In the present study on evaluation of the MRI findings we found that in 34 cases a

single opening was seen. in 1 case multiple openings (two openings) were seen

representation was seen , on the same side

External opening

34 35

30

25

20

15

10

51

0

single

multiple

~ 42 ~

NUMBER OF INTERNAL FISTULA TRACTS - MRI

TRACTS FREQUENCY PERCENT1 tract 29 80.2

2 tract 3 9.9

3 tract 2 6.6

4 tract 1 3.3

TABLE 11: NUMBER OF INTERNAL FISTULA TRACTS

GRAPH 11: NUMBER OF INTERNAL FISTULA TRACTS

In the present study on evaluation of the MRI findings we found that in 29cases a

single opening was seen.

30

25

20

15

29 10

5

3 2 1 0

1 tract 2 tract 3 tract 4 tract

~ 43 ~

ST . James's university hospital classification type -MRI

ST . JAMES'S UNIVERSITY

I 16 46II 2 11III 12 34IV 4 6V 1 3Total 35 100

TABLE 12: ST. JAMES'S UNIVERSITY HOSPITAL CLASSIFICATION

TYPE

GRAPH 12: ST. JAMES'S UNIVERSITY HOSPITAL CLASSIFICATION

TYPE

In the present study on evaluation of the MRI findings we found that in 16 cases a

single opening Belonged to Type I and 12 Cases to Type III St. James's university

hospital classification type

4

3

3 St. James's university hospital classification2

23

1

11

5 82 1

0I I II I V

~ 44 ~

SUPRA LEVATOR EXTENSION- MRI FINDINGS

NO 34 98.3

YES 1 1.7

TOTAL 35 100.0

TABLE 13: SUPRA LEVATOR EXTENSION

GRAPH 13: SUPRA LEVATOR EXTENSION

In the present study on evaluation of the MRI findings we found that in 34 cases

there was no Supra-levator extension

70 Supra levator extension 60

50

40

30 34

20

10 1

0

No Yes

~ 45 ~

DISCUSSION

As multiple medical and surgical treatment options exist, imaging plays a critical

role in accurately characterizing perianal fistulas to individualize management

strategy. Differences in the classification scheme have been shown to have an

impact on prediction of prognosis. Imaging options include fistulography,

computed tomography (CT), anal endosonography, and MRI.

MRI classification of perianal fistulae has been significantly associated with

clinical outcome, with MRI grades differing significantly between satisfactory and

unsatisfactory outcomes

MRI evaluation of perianal fistula has also revealed additional diagnostic

information in the preoperative setting, especially for complicated disease

MRI evaluation and classification of perianal fistulae can be standardized with a

high degree of diagnostic accuracy therefore reducing interobserver variability.

COMPARISON OF GENDER DISTRIBUTION

In our study we found that 92 % were males as compared to 8 % females were

affected with fistula .

Rishi Philip Mathew 62 , 28 (93%) were males and 2 (7%) were females.

Study Gender distribution

Marina Garcés-Albir, et al 14 patients (11 men and 3 women)

Sthela Maria Murad-Regadas et al Seventy-four (49%) patients (M: 41, F: 33

our study 32 patients (28 men and 2women)

~ 46 ~

TABLE 24: COMPARISON OF GENDER DISTRIBUTION

COMPARISON OF AGE DISTRIBUTION

The mean age on our study was 43(sd+) 2.3 years. The youngest case was 24

years and eldest was 82 years of age .most cases were in the age group 26-45 years

Study Age distribution

Dariusz Waniczek et al 56 mean age of 47 years (range 21-77),

our study 26-45 years , 34(sd+) 2.3 years

TABLE 25: COMPARISON OF AGE DISTRIBUTION

TYPE OF FISTULA

In our study intersphincteric fistulas (24 cases , 60 %)were the most common

variety as opposed to the study by Marina Garcés-Albir, et al 55low

transsphincteric fistulas were the most frequent type found (33, 47.1%)

followed by high transsphincteric (24, 34.3%) and

intersphincteric fistulas (13, 18.6%).

Marina Garcés-Albir, et al 55in their study showed that the intraoperative

findings were consistent with radiological descriptions of 13 MRI fistulographies.

Only in one case, according to surgery findings, it was a transsphincteric fistula

with an abscess in the ischioanal fossa, with an orifice in the posterior crypt; the

radiologist described it as a transsphincteric, internal blind fistula.

Maier et al. 48 showed a statistically higher efficiency in the detection of

perianal fistulas and

abscesses in 39 patients with the use of magnetic resonance (84% sensitivity) as

~ 47 ~

compared to endosonography (60% sensitivity). False-positive results were present

in 6 patients (15%) examined with MR and in 10 (26%) examined with

endosonography

Beets-Tan et al. 49 assessed the usefulness of the method by comparing the

results of MRI in patients before surgery with intraoperative findings. They

proved that its sensitivity and specificity for fistulous canal detection amounted to

100% and 86%, respectively. For a horseshoe fistula this was 100% and 100%, and

for internal openings – 96% and 90%.

MR imaging findings were correlated with the intraoperative surgical finding IN a

study by Jajoo et al .57 MR imaging shows 7 fistulous patients with side

branching and 16 with abscess cavity which was 100% intraoperatively correlated.

Fifty-six patients out of 60 completely correlated with MRI for primary track

which was clinically significant. MRI had 96% sensitivity and 100% specificity for

primary tract and internal opening an7 100% sensitivity and specificity for abscess

and multiple tracks.

Regina G. H. Beets-Tan et al68 ). The sensitivity and specificity for detecting

fistula tracks were 100% and 86%, respectively; abscesses, 96% and 97%,

respectively; horseshoe fistulas, 100% and 100%, respectively; and internal

openings, 96% and 90%, respectively

Rishi Philip Mathew 62 MRI had a sensitivity and specificity of 96.15% and 75%

respectively. J A Spencer et al 67 in their study found MR imaging had a

sensitivity of 97%, a specificity of 67%, a positive predictive value of 88%, and a

negative predictive value of 89%.

~ 48 ~

CONCLUSION

Perianal fistulae is a clinical entity with significant patient morbidity. While

multiple surgical options exist, recurrence rates and the risk of fecal incontinence

are important considerations in management strategy. MRI provides information

about the fistulae with great anatomic detail with respect to secondary tracks and

abscesses as well as the surrounding pelvic organs. The use of MRI for the

identification and classification of perianal fistulae can provide essential

information that has been shown to have both preoperative and prognostic value.

Preoperative precise localization of the fistulous tract with its internal and external

orifice is the main purpose of the diagnostics in perianal fistulas and, to a large

extent, determines the effectiveness of surgery.

~ 49 ~

SUMMARY

In the present study on evaluation of the MRI findings we found that

In 34 cases a single opening was seen. in 1 case multiple openings (two openings)

were seen representation was seen , on the same side.

Transphincteric tract in 31cases, 87%.

33 cases Horse shoe shaped ramification was seen.

30 cases Intersphincteric fistulous was seen

33 cases 94% had a single opening.

32 cases 92 % were males as compared to 8 % females were affected with fistula

The mean age on the present study was 34(SD+) 2.3 years. The youngest case

was 24 years and an elder was 62 years of age .most cases were in the age group 26-

45 years.

In the present study and 7 cases were presented with swelling

~ 50 ~

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61. Torkzad MR, Karlbom U. MRI for assessment of anal fistula. Insights into

imaging. 2010 May 1;1(2):62-71.

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CONSENT

INFORMED CONSENT

I have read and understood the information, it has been read to me and explained in an

understandable language and the language I understand, about the research project

:MAGNETIC RESONANCE IMAGING EVALUATION OF PERIANAL

FISTULAS. I have had the opportunity to ask questions about it and any questions that

I have asked have been answered to my satisfaction. I consent voluntarily to participate

as a participant in this research.

Name of Participant Signature of Participant

Date Day/month/year

If illiterate :

I have witnessed the accurate reading of the consent form to the potential participant,

and the individual has had the opportunity to ask questions. I confirm that the

individual has given consent freely.

Name of witness AND Thumb print of participant Signature of

witness Date __________

Day/month/year Statement by have accurately read out the information sheet to the

potential participant, and to the best of my ability made sure that the participant

understands that various sequences of MRI will be performed for fistulas evaluation. I

confirm that the participant was given an opportunity to ask questions about the study,

and all the questions asked by the participant have been answered correctly and to the

best of my ability. I confirm that the individual has not been coerced into giving

consent, and the consent has been given freely and voluntarily.

A copy of this ICF has been provided to the participant.

Name of Researcher/person taking the consent Signature of

Researcher /person taking the consent Date

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ETHICAL COMMITTEE REPORT

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PRO-FORMA

Name IP No.

Age OP No.

Sex

Case No.

MR no:/Date:

CLINICAL EXAMINATION

SIGNS

Yes/ NO /Explanation

Tenderness

Swelling

Discharge

No of external openings

No of internal openings

Site of internal openings Site of external openings Abscess

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A. Case Proforma

NAME AGE

Clinical Features Mri Features

Intersphincteric Fistulous Tract Horse Shoe Shaped Ramification Transphincteric

Tract,

Internal Opening

External Opening Cm Above The Anal Verge. Tracts

Supra Levator Extension

St. James's University Hospital Classification Type Others

B. Sample Consent Form

I, Dr.Rashmi Aravind Patel. Post graduate in Radiodiagnosis conducting trial for

award of MD degree in Radiodiagnosis.

The topic of the study is:

MAGNETIC RESONANCE IMAGING EVALUATION OF PERIANAL

FISTULAS I have been briefed on the foregoing research being conducted by

Dr.Rashmi Aravind Patel and it has been conveyed to me in my own language .I

have had the opportunity to ask questions about it & all questions that I have

asked have been answered to my satisfaction. I consent voluntarily to

participate as a participant in this research & understand that I have the right to

withdraw from the research at any time without in any way affecting my medical

care.

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Name & Signature Of Participant With The Date And Time ----------------------------

If illiterate: A literate witness must sign ( If possible this person should be

selected by the participant and should have no connection to the research team)

I have read and witnessed the accurate reading of the consent form to the

potential participant and the individual has had the opportunity to ask questions,

I confirm that the individual has given consent freely.

Name of the witness...........................................................

Signature of witness……………….............................……

Date: (d/m/y)……………....................................................

Name & Thumb impression Of Participant With The Date And Time

I have read and witnessed the accurate reading of the consent form to the

potential participant and the individual has had the opportunity to ask questions,

I confirm that the individual has given consent freely. In case of any doubt I have

been asked to contact:

Dr.Rashmi Aravind Patel. Post graduate in Radiodiagnosis

Name of Researcher:……………………………………………………… Signature

of researcher:……………………………………………………

Date :( d/m/y)………………………………………………………………

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MASTER CHART

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D. KEY T0 MASTERCHART

+ - PRESENT

- ABSENT M- MALE

F- FEMALE M- MIDLIE L – FEFT

R – RIGHT

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ANNEXURES

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