WHAT IS A RECTOVAGINAL FISTULA?

Fistula is derived from the Latin word that means "pipe." A fistula is an abnormal connection between two epithelialized surfaces. So rectovaginal fistula (RVF) is medical name given to the condition where there is an abnormal connection between rectum (or even anal canal) and Vagina. It is an uncommon but quite troublesome disease both for the patient and surgeon. RVFs can be classified into low and high varieties. Low RVF is between the lower third of the rectum or anal canal and the lower half of the vagina. A high fistula is between the middle third of the rectum and the posterior vaginal fornix. Small-sized fistulas are less than 0.5 cm in diameter, medium-sized fistulas are 0.5–2.5 cms, and large-sized fistulas exceed 2.5 cms.

RVFs can be both congenital (Present since birth) and acquired. Congenital RVFs generally occurs along with other anomalies. Most of the RVFs are acquired. Acquired fistulas can occur due to various causes. These include Trauma -including operative, obstetric, and traumatic injuries.

Infection-Any infective process contiguous with the rectovaginal septum (a thin septum present between anorectum and vagina) can cause RVF e.g perennial or bartholin gland infection, diverticular disease, Tuberculosis and lymphogranuloma venererum etc.

Inflammatory bowel disease (IBD) like crohn's disease and ulcerative colitis.

Various cancers of colon, rectum, cervix and vagina or uterus. Radiations given for treating carcinomas of pelvic organs especially carcinoma of cervix or endometrium can also cause RVFs.

All the patients of the vaginal passage of gas and stool can cause physical symptoms due to inflammation and irritation. Patients may also suffer from significant psychosocial and sexual dysfunction.

Whatever may be the cause, RVF will cause some symptoms and these may be very distressing to the patient. Symptoms will vary according to the size, location and cause of the RVF.

Rectovaginal fistula may be extremely debilitating. If the opening between the rectum and vagina is wide it will allow both flatulence and feces to escape through the vagina, leading to fecal incontinence. There is an association with recurrent urinary and vaginal infections accompanied by malodorous discharge.

Intestinal symptoms of diarrhea, persistent feeling of incomplete bowel evacuation), rectal bleeding, mucus discharge and abdominal cramps secondary to the underlying cause like IBD may be there.

DIAGNOSIS

A thorough history and physical examination of the patient are necessary to help identify the cause of the fistula, as well as to assess its location, any ongoing inflammation, and whether a sphincter defect is present or not. Continence evaluation is of paramount importance in RVFs following perineal lacerations. All this information is essential prior to surgical treatment. Procto-sigmoidoscopy(An examination with the help of a tube like instrument fitted with light and camera to take pictures of anal canal and lower part of large intestine) should be done. The fistulous opening may be seen as a small dimple or pit and occasionally can be gently probed for confirmation. Flexible endoscopy (sigmoidoscopy or colonoscopy) is used to fully evaluate the possibility of any lesion in the intestine as a cause of RVF. Evaluation of established RVFs with endo-rectal ultrasound and trans-vaginal ultrasound examination is more important if the patient complains of incontinence or if the underlying cause is obstetric trauma.

High fistulas may not be readily apparent on physical examination or vaginal inspection and may even be missed by endoscopy. Methylene blue enema with a vaginal tampon in place, looking for staining on the tampon is used to confirm the diagnosis. Vaginography with a water soluble contrast medium has a reported sensitivity of 79% to 100%. CT and MRI also play a role in the diagnosis and evaluation of the RVF as they may give insight into the underlying cause of the fistula.

The management of RVF depends on size, location, cause, anal sphincter function and overall health status of the patient. It also depends on the skill and judgment of the surgeon. Treatment of established RVFs should be surgical. The treatment of RVF must be tailored to the individual fistula. Basic aim of surgery is to close the abnormal connection between rectum and vagina. For low RVF there are various techniques and the surgeon may approach the fistulous track through Vagina, anal canal or perineum. Transabdominal approach (approaching the fistula through abdomen) is the standard surgical approach for high fistulas. Different surgical techniques have been described. These include fistula division and closure with or without bowel resection and use of local flaps, such as the bulbocavernosus flap and a variety of muscle and musculocutaneous flaps for repair of large defects.

Ksharsutra Management For RECTOVAGINAL FISTULA