fistula in ano
TRANSCRIPT
FISTULA IN ANO – PERIANAL FISTULA
• MERCURY IMAGING INSTITUTE • SCO 172-173 SEC 9C
CHANDIGARH• MERCURY IMAGING CENTRE • SCO 16-17 SEC 20D
CHANDIGARH
18 YR MALE PATIENT WITH H/O TRAUMA OVER ANAL
VERGE REGION – PRESENTLY UNDER ASSESMENT FOR
PERIANAL FISTULA’S. PRESENT CASE –
GRADE ONE INTERSPHICTERIC FISTULOUS
TRACTS
BENEVOLENT DISPENSARY
TOST MARK’S HOSPITAL LONDON
Frederick Salmon
STARTED 'The Infirmary for the Relief of the Poor afflicted with Fistula and other Diseases of the Rectum'.PERFORMED 3500 OPERATIONS WITH NOT EVEN SINGLE FATALITY.
LEVATOR SLING
ISCHIO RECTAL FOSSA
ISCHIOANAL FOSSA
ANATOMY
IMPORTANT POINTS
EXTERNAL ANAL SPHINCTER • Voluntary control• Similar in signal to levator sling • 15% of the anal tone.• Straited muscle – continous with
the puborectalis / levator muscle
INTERNAL ANAL SPINCHTER• Involuntary Control• Smooth Muscle Responsible For
85 % Of The Anal Tone.• Continous With Circular Smooth
Muscle Of The Rectum.• Similar In Signal To Anal
Musculature• Relatively Hyperintense On Fat
Sat Sequences.
IMPORTANT POINTS ANAL CLOCK
• LITHOTOMY POSITION• DEFINE THE INTERNAL
OPENING 12”o clock – Anterior perineum
3“O CLOCK - Left Lateral aspect
6 ‘ o clock - Natal cleft
9 ‘ o clock – Rt side of the perineum
TRANSVERSE ANAL LINE • Define the cutaneous
opening (Predicts the internal opening)
CUTANEOUS OPENING
Rt side – Posterior to the anal canal
Lt side – Posterior to the anal canal
TRACT
Rt side – linear longitudinal tract with no secondary ramifications –present in the intersphincteric plane
Left side – linear longitudinal with no seconday ramifications- present in the intersphincteric plane
INTERNAL OPENING6”0clock – Rt side of the anal canal
3’0clock – left lateral aspect.
3D
BRIEF ABOUT PERIANAL FISTULA’S
ETIOLOGY• Crptoglandular hypothesis • Crohn disease • Tuberculosis • Trauma during childbirth,• Pelvic infection • Pelvic malignancy• Radiation therapy
PREOPERATIVE EVALUATION OF PERIANAL FISTULAS
• To define relation of the fistulous tract with sphincter complex ( intersphicteric , trans-sphincteric, suprasphicteric ).
• Define Secondary tracts/ Ramifications.
• Define horseshoe tracts.
St James's University Hospital ClassificationMR Imaging Grading of Perianal Fistulas
Grade 1: Simple Linear Intersphincteric Fistula.—
Grade 2: Intersphincteric Fistula with Abscess or Secondary Track.—
No secondary tract / ramifications
Secondary tract / ramifications present but
pathology is confined by the external sphincteric plane
St James's University Hospital ClassificationMR Imaging Grading of Perianal Fistulas
Grade 3: Trans-sphincteric Fistula.Grade 4: Trans-sphincteric Fistula with Abscess or Secondary Track within the Ischiorectal Fossa.
Transsphincteric extension with tract extending through the ischirectal / ischio anal
region.
Trans-spincteric fistula with absecss / secondary infection
in the ischiorectal fossa
St James's University Hospital ClassificationMR Imaging Grading of Perianal Fistulas
Grade 5: Supralevator and Translevator Disease.
Suprasphincteric ---- high extension through intersphincteric planeExtrasphincteric : Outside the sphincteric mechanism Translevator / supralevator.
CONTRST MR – EXTRA EDGE
DELINEATES THE TRACTS , INFECTIVE FOCI IN A BETTER WAY.