Editing Rectovaginal fistula

== Aetiology: ==

* Obstetric - most common
** 3% of 3rd and 4th degree      perineal tears go on to develop rectovaginal fistula
** Often a/w anterior anal      sphincter defects
* Crohn's disease
** Up to 10% of all female      Crohn's patients
** High recurrence rate in this      population
** Amost all will require EUA      before a decision is made about formal repair
** Optimise medical therapy -      fistula may resolve with immunologics
* Iatrogenic
** Surgery
*** Fistulotomy
*** Hysterectomy, rectocoele       repair, LAR, prolapse/haemorrhoidectomy
** Radiotherapy
*** Ensure to rule out       malignancy with biopsies
* Neoplasia
** Anal
** Rectal
** Vaginal
** Cervical
* Infectious
** Cryptoglandular abscess
** Diverticulitis
** TB

== Presentation ==

* Passage of stool or gas via     vagina
* Recurrent UTI
* Dyspareunia
* Vaginal discharge

== Exam ==

* DRE - indurated fistula tract
* Anoscopy or vaginal speculum     exam - granulation tissue often visible - gentle probing often reveals     tract
* Tampon test - put in a     tampon, then give methylene blue dye enema, and walk around for 20     minutes. If tampon goes blue, a fistula is highly suspected.
* If patient has IBD, EUA is     generally necessary to define tract and evaluate for degree of     inflammation


'''Principles of pre-op workup: identify fistula, determine the cause, evaluate extent of disease, and identify surrounding structures'''

== Investigation: ==

* MRI
* Endoanal USS
* Pelvic floor physiologic     testing (anorectal manometry) - indicated when suspicion for anal     sphincter injury or fecal incontinence, which may impede recovery     post-repair
* Colonoscopy/CT depending on     aetiology

== Classification ==

* According to their relation     to the sphincter complex
** High: above
** Low: at or below (also      referred to as anovaginal)
*** Almost always caused by       obstetric trauma
* Alternatively:
** Simple: middle or lower      portion of rectovaginal septum, <2.5cm in diameter, and caused by      local trauma or infection
** Complex: >2.5cm, upper      portion of rectovaginal septum, secondary to causes other than trauma and      infection

== Pre-op ==

* Phosphate enema morning of     procedure

== Surgical management: ==

* Local sepsis is an absolute     contraindication to repair - may need to drain abscesses, treat infection     (?seton), and wait
* Delay 3-6 months after birth     if that is the cause, to allow local inflammation to subside and fibrosis     to develop
* Transanal
** Fistulotomy
*** Two-stage: first, place       seton; then, lay open tract
*** Risks sphincter damage and       incontinence
*** Very rarely used today
** Endorectal advancement flap
*** Indicated in low vaginal       fistulas, without sphincter defects
*** Good to perform repair from       high-pressure side of fistula
*** Preserves sphincter
*** Performed transanally.       Raise flap, excise fistula, close.
*** Complications: flap       failure, ischaemia
*** Post-op: high-fibre diet,       stool softeners, sitz baths
** Fibrin glue
** Bioprosthetics
*** Very limited experience
* Transvaginal
** Vaginal advancement flap
*** Similar to rectal       advancement flap
*** Advantage is that you use       healthy, pliable, well-vascularised vaginal tissue to close the fistula
*** Disadvantage - closure is       on the low-pressure side of the fistula
*** Can be advantageous to go       vaginal when anorectal stenosis is present, e.g. in Crohn's disease -       studies show no difference in orifice chosen
*** Also good if anal       advancement flap has already failed once
* Transperineal
** Episioproctotomy and layered      closure
*** Converts fistula in a       fourth-degree perineal tear by dividing all the tissue between the       rectum and the vagina through the perineal body
*** Layers
**** Rectal mucosa
**** Rectal and vaginal        muscular walls
**** Vaginal mucosa
*** Dehischence risks       significant incontinence - worse than pre-op - since a full-thickness       defect is being created
*** Should only be attempted by       experienced surgeons
** Transperineal ligation with      a LIFT procedure, overlapping sphincteroplasty
** Interposition flaps
*** Most commonly gracilis and       bulbocavernosus flaps
*** Feval diversion generally       undertaken prior
* Transabdominal
** Rectal resection/advancement
*** Indicated in       circumferential or stricturing disease (Crohn's) or for high/complex       fistulae
** Primary repair with omental      interposition
*** Best suited for high       fistulae or those with multiple failed transanal/vaginal/perineal       approaches


[[Category:Colorectal]]