Anal Fistulas and Fissures 

Updated: Nov 09, 2018
Author: Bruce M Lo, MD, MBA, CPE, RDMS, FACEP, FAAEM, FACHE; Chief Editor: Barry E Brenner, MD, PhD, FACEP 

Overview

Background

An anal fissure is a superficial linear tear in the anoderm that is distal to the dentate line. Anal fissures are often associated with local trauma such as the passage of hard stools or anal trauma, but can also be due to secondary causes such as inflammatory bowel disease. Anal fissures are among the most common anorectal disorders in the pediatric population. Adults are also affected, although it is thought to be underreported in the adult population.

Fissures are defined as acute if present for less than 8 weeks, and they are defined as chronic if present for more than at 8-12 weeks weeks.[1]

An anal fistula is an inflammatory tract between the anal canal and the skin. The 4 categories of fistulas, based on the relationship of fistula to sphincter muscles, are intersphincteric, transsphincteric, suprasphincteric, and extrasphincteric.[2]

An anal fistula can be categorized as either simple or complex. A simple anal fistula includes low transsphincteric and intersphincteric fistulas that cross 30% of the external sphincter. Fistulas are complex if the primary track includes high transsphincteric fistulas with or without a high blind tract, suprasphincteric and extrasphincteric fistulas, horseshoe fistulas, multiple tracks, anteriorly lying track in a female patient, and those associated with inflammatory bowel disease, radiation, malignancy, preexisting incontinence, or chronic diarrhea. Note the image below.

Anal fistulas and fissures. This patient reported Anal fistulas and fissures. This patient reported constipation.

Pathophysiology and Etiology

Anal fissure

In anal fissures, the anus distal to the dentate line is involved. About 90% of anal fissures occur in the posterior midline. Ten percent are found in the anterior midline, more commonly in women. Only 1% occur off midline.

While the exact etiology is often unknown, passage of hard stools and anal trauma are often associated with anal fissures. Other causes of anal fissures can be observed in patients with chronic diarrhea, during childbirth, and those with a habitual use of cathartics. When an anal fissure occurs in an atypical location, it may be associated with syphilis and other sexually transmitted diseases, tuberculosis,[3] leukemia,[4] inflammatory bowel disease such as Crohn disease, previous anal surgery, HIV disease, and anal cancer. Once a fissure is formed, ongoing pain can cause the internal analsphincter to spasm (hypertonicity), which causes the wound edges of the fissure to pull apart, impairing healing. Local ischemia is also thought to contribute to anal fistulas, especially in the posterior quadrant where blood flow is significantly less than other quadrants. As the anal sphincter continues to spasm, increased pressures are thought to further impede blood flow.[5, 1]

Evidence suggests that blood flow to the anal canal and internal anal sphincter tone play a role in the development and healing of anal fissures. Decreased blood flow has been described in chronic, nonhealing fissures. Hypertonicity of the internal sphincter may also cause decreased blood flow in the area of a fissure.[6, 7, 8]

Anal fistula

Most anal fistulas originate in anal crypts, which become infected, with ensuing abscess formation. When the abscess is opened or when it ruptures, a fistula is formed. An anal fistula can have multiple accessory tracts complicating its anatomy.

Other causes of anal fistulas include opened perianal or ischiorectal abscesses, which drain spontaneously through these fistulous tracts. Fistulas are also found in patients with inflammatory bowel disease, particularly Crohn disease.[9] The incidence of fissures in Crohn disease is 30-50%. Perianal activity often parallels abdominal disease activity, but it may occasionally be the primary site of active disease.

Anal fistulas can also be associated with diverticulitis, foreign-body reactions, actinomycosis, chlamydia, lymphogranuloma venereum (LGV), syphilis, tuberculosis,[3] radiation exposure, and HIV disease. Approximately 30% of patients with HIV disease develop anorectal abscesses and fistulas.

Anal fistulas are classified into the following 4 general types:

  • Intersphincteric - Through the dentate line to the anal verge, tracking along the intersphincteric plane, ending in the perianal skin

  • Transsphincteric - Through the external sphincter into the ischiorectal fossa, encompassing a portion of the internal and external sphincter, ending in the skin overlying buttocks

  • Suprasphincteric - Through the anal crypt and encircling the entire sphincter, ending in the ischiorectal fossa

  • Extrasphincteric - Starting high in the anal canal, encompassing the entire sphincter and ending in the skin overlying the buttocks

Epidemiology

Anal fissures affect males and females equally; however, an anterior fissure is more likely to develop in women (25%) than in men (8%).[5] Although anal fissures are the most common cause of rectal bleeding in infants, they are primarily seen in young adults. Eighty-seven percent of people with a chronic anal fissure are between the ages of 20 and 60 years. Anal fissures in children may indicate sexual abuse.

Anal fistulas are a complication of anorectal abscesses, which are more common in women than in men. For reasons of intrinsic anatomy, rectovaginal fistulas are found only in women. Approximately 30-50% of patients with an anorectal abscess form an anal fistula.[10] and approximately 80% of anal fistulas arise from anorectal infection.[11]

Prognosis

Approximately half of uncomplicated fissures resolve in 2-4 weeks with supportive care.[1] Fissures that heal with conservative treatment can recur, depending on the type of treatment the patient has undergone (ranging from 16% to more than 50%).[5] Chronic anal fissures frequently require surgical treatment.

Surgical treatment of anal fissures is associated with some degree of incontinence in approximately 14% of patients.[12]

Prognosis for fistulas is excellent after surgery, with recurrence rates around 7-21% depending on the complexity and location of the fistula.[11, 13] Use of fibrin glue or fistula plug has variable success rates.

 

Presentation

History

Anal fissures may present with rectal pain described as burning, cutting, or tearing that occurs with bowel movements. Spasm of the anus is very suggestive for an anal fissure. A history of constipation or passage of hard stools may be present. Typically, bright-red blood appears on the surface of stools, but blood usually is not mixed into stool and is present only in a small amount. Occasionally, blood is found on toilet paper after wiping. The patient may report no bleeding.

A patient with an anal fistula may complain of recurrent malodorous perianal drainage, pruritus, recurrent abscesses, fever, or perianal pain due to an occluded tract. Patients may report a recent perianal or buttock abscess. Pain occurs with sitting, moving, defecating, and even coughing. It usually is throbbing in quality and is constant throughout the day. Pain occasionally resolves spontaneously with reopening of a tract or formation of a new outflow tract.

Physical Examination

The physical examination of patients with fistulas or fissures begins by optimizing patient placement; place the patient in the left lateral decubitus position with knees drawn up toward the chest.[14] Examine the patient carefully to help avoid inflicting further pain or sphincter spasm. Rectal examination is generally difficult to tolerate because of sphincter spasm and pain. Examination may be facilitated by application of a topical anesthetic, such as lidocaine jelly, before digital rectal examination (DRE); however, a DRE may not be tolerated by some patients.

Most fissures are visible externally when the buttocks are gently spread apart. Having the patient bear down as if having a bowel movement may also help visualize an anal fissure. Acute fissures appear similar to a laceration, while a chronic fissure may be accompanied by external skin tags distally and hypertrophied anal papillae proximally. Most tears are found in the posterior midline. Acute fissures are erythematous and bleed easily.

With chronic fissures, the classic fissure triad may be seen, as follows:

  • Deep ulcer

  • Sentinel pile, which forms when the base of the fissure becomes edematous and hypertrophic (a resolving sentinel pile can result in a permanent skin tag or may become associated with a fistulous tract)

  • Enlarged anal papillae at dentate line, only seen in the OR under general anesthesia or if prolapsed

Bidigital rectal examination in a patient with a fistula-in-ano may reveal an indurated tract or cord. A fistula can be identified by small circles of granulation tissue, which exude pus when compressed if tissue is patent. A fistulous tract that opens internally can be visualized with the aid of an anoscope. Inguinal lymph nodes may be enlarged and painful.

If an abscess is also present with an anal fistula, cardinal signs of inflammation, rubor, dolor, calor, and tumor (eg, erythema, pain, increased temperature, edema) may be found.

Complications

Constipation or fecal impaction may occur. The pain from an anal fissure can be so overwhelming that it discourages people from defecating. Acute fissures can become chronic, and sentinel pile can result. A permanent skin tag can result, and fistulas may form.

The following complications may occur with surgical intervention[2, 15] :

  • Urinary retention

  • Bleeding

  • Abscess formation

  • Flatus, liquid, and stool incontinence

  • Recurrence of fissures

Carcinoma has been reported in cases of chronic untreated anorectal fistulas.

 

DDx

 

Workup

Approach Considerations

Diagnosis of an anal fissure is primarily based on the history and physical examination. No specific testing is needed for diagnosing anal fissures unless atypical or multiple fissures are present, suggesting either an infectious or other etiology.

Evaluation of an anal fistula depends on the clinical status of the patient. If a concurrent abscess is present, and the location and size is not well characterized, advanced imaging may be needed. Blood work should be reserved for patients with clinical signs of sepsis or those who appear toxic. Wound culture may also be indicated if there is concern for possible infectious etiologies such as syphilis or HIV infection. If clinically warranted, a workup for other etiologies such as Crohn disease may be indicated.

If the extent of the fistula is not well characterized by physical examination, advanced diagnostics may be indicated to evaluate the anatomy of a complex fistula.

 

Treatment

Approach Considerations

Anal fissure

Anal fissures can cause a vicious cycle in which the patient, in anticipation of pain associated with bowel movement, resists the urge to defecate, causing stools to become larger and harder, resulting in more pain with defecation. Treatment should be focused on breaking this cycle to allow healing. If the patient is having a great deal of pain, a topical anesthetic may be applied. Anal health care is particularly important.[16] Diet modification to soften stools is also indicated in patients with anal fissures. Patients should increase fruits, vegetables, and soluble and insoluble fibers in their diets and increase fluid intake to treat the acute phase and to prevent recurrence. Bulking agents such as psyllium may be prescribed. Approximately half of all anal fissures heal with nonoperative therapy within 2-4 weeks.

Use the WASH regimen in treatment of anal fissures, as follows:

  • W arm water; sitz bath after bowel movement

  • A nalgesics

  • S tool softener

  • H igh-fiber diet

Medications may also be prescribed for anal fissures, such as topical nitrates, calcium channel blockers, and onabotulinumtoxinA injections, and are considered first-line therapy.[17] These medications reduce anal sphincter tone or vasodilate, which, in turn, increases anodermal blood flow. When conservative treatment fails, surgical therapy may be an option to treat anal fissures.

A systematic review (inception to March 2017) and meta-analysis of 6 randomized controlled trials comprising 393 patients with chronic anal fissue found fewer side effects with botulinum toxin than with topical nitrates, but there were no significant differences in incomplete fissue healing or recurrence.[18]

Potential alternative strategies under investigation for treatment of anal fissues include using textile-based carrier systems loaded with microparticles containing nifedipine and lidocaine hydrochloride[19] as well as topical myoxinol (hydrolyzed Hibiscus esculentus extract).[20]

Historically, surgical therapy was common for the treatment of anal fissures and is considered superior to nonoperative therapies. However, due to the risk of complications, including incontinence, surgical therapy is often reserved when conservative treatment fails to heal anal fissures.

Anal fistula

Treatment of anal fistulas depends on (1) the location of the fistula, (2) evidence of sepsis or a large abscess, or (3) worrisome findings on physical examination. If an abscess is present, drainage is indicated. Intravenous antibiotics, antipyretics, and analgesics are provided as needed. However, simple rectal abscesses do not typically need antibiotics.[21] If the patient also has sepsis, intravenous fluids or a pressor may be necessary. Depending on the presence of systemic symptoms and the condition of the patient, surgery may be necessary.

For anal fistulas, outpatient follow-up with a surgeon is indicated if consultation did not take place at the time of presentation. Surgical therapy is often indicated for healing of an anal fistula. The surgical approach is dependent on whether the fistula is simple or complex, as well as the risk of complications such as incontinence. A gastroenterologist should be consulted if inflammatory bowel disease is suspected. Asymptomatic anal fistulas from Crohn disease are not managed by surgery. However, if the patient is symptomatic, surgical management should be considered.

Antibiotics should be reserved for those with overlying cellulitis or those with sepsis. Otherwise, symptomatic treatment with analgesics should be considered.

In an open-label, single-arm clinical study by de la Portilla et al, local injections of expanded adipose-derived allogeneic mesenchymal stem cells proved beneficial for patients with perianal fistulas associated with Crohn disease.[22] The study involved 24 patients, with investigators finding that in 69.2% of cases, the number of draining fistulas was reduced, while in 56.3% of patients, the treated fissures closed completely, and in 30% of cases, all existing fistula tracts completely closed.[22]

A systematic review of the literature concluded that the advancement flap technique to treat anal fistulas in patients with Crohn disease is an adequate alternative management option.[23]

Guidelines

Consensus guidelines from a working group of the World Congress of Gastroenterology call for a multidisciplinary approach to the management of perianal fistulas associated with Crohn disease. The guidelines list surgical drainage of the abscesses as first-line treatment prior to starting immunosuppressive therapy. Definitive fistula repair with surgical treatment such as fistulotomy, ligation of the intersphincteric fistula tract (LIFT), or the use of mucosal advancement flaps, plugs, or fibrin glue should be considered only if there is no luminal inflammation. The guidelines also state that anti-tumor necrosis factor can provide first-line medical therapy, with an option being to combine this treatment with the use of antibiotics and/or thiopurines.[24]

Pharmacologic Treatment of Anal Fissures

Calcium channel blockers

Oral and topical calcium channel blockers (diltiazem and nifedipine) have been shown to be effective treatment options for anal fissures. Calcium channel blockers work by vasodilating blood vessels. In one review, calcium channel blockers were shown to be as effective as topical nitrates. Adverse effects such as headaches are common, especially with the use of oral calcium channel blockers.[25] Oral calcium channel blockers have been shown to yield decreased healing rates compared with topical calcium channel blockers, as well as higher rates of adverse effects.[26]

However, a prospective controlled trial that compared 2% diltiazem versus lateral internal sphincterotomy (LIS) for treatment of chronic anal fissures in 90 patients found LIS was more effective for not only complete healing at 6 weeks (96%) than diltiazem (71%) but also for pain relief.[27]  The investigators suggested the use of topical diltiasem may be an initial conservative therapeutic option before consideration of surgical intervention.

Topical nitrates

Topical nitrates have been shown to be effective in the treatment of anal fissures. It is applied directly to the anus and vasodilates blood vessels. In a Cochrane review, topical nitrates were better than placebo in healing anal fissures (48.9% vs 35.5%). However, late recurrence was common (>50%) and headaches occurred frequently, causing cessation of therapy (up to 30%).[25]

In a study of 60 patients with chronic anal fissue, endoanal application of 375 g of 0.2% topical glyceryl trinitrate appeared to be associated with a slight reduction in headache intensity compared to perianal application, with a similar healing rate.[28]

Different dosing of topical nitrates has also been studied, from 0.05% to 0.4%, without a difference in healing rates.[29, 30, 31] Topical nitrates have also been compared with nitroglycerin patches applied to a remote area, with similar cure rates.[32]

One small randomized controlled trial between topical diltiazem gel (2%) or glyceryl trinitrate ointment (0.2%) showed a healing rate of 92% with diltiazem compared with 60% with glyceryl trinitrate (P< .001).[33] Adverse effects were more common with glyceryl trinitrate.

In a randomized clinical trial, Berkel et al investigated whether botulinum toxin A (Dysport) is more effective than isosorbide dinitrate ointment (ISDN) in the primary treatment of chronic anal fissure. Sixty patients were randomized to receive either ISDN 10 mg/ml (1%) (n = 33) or injection with 60 units of Dysport (n = 27). The primary end-point was the percentage of complete fissure healing after 8 weeks. After a median of 9 weeks, complete fissure healing was noted in 18 of 27 patients in the Dysport group, compared with 11 of 33 patients in the ISDN group (P = 0.010). Absolute improvement of pain scores after 9 weeks was similar between groups. Compared to patients treated with ISDN, patients treated with Dysport had fewer side effects. Of the patients with a healed fissure, 28% of the Dysport group and 50% of the ISDN group had a recurrence within 1 year. In the primary treatment of chronic anal fissure, Dysport is more effective than ISDN ointment and has fewer side effects.[34]

OnabotulinumtoxinA

OnabotulinumtoxinA is used typically to treat muscle hypertonia and cosmetic disorders. Typically, onabotulinumtoxinA is injected into the internal sphincter, reducing hypertonia. Various dosing schemes have been used, and it is typically injected on both sides of the anal fissure. Fissure healing appears to be equally effective with lower or higher doses of botulinum toxin, although lower doses reduced the risk of incontinence and recurrence over the long term.[35]

OnabotulinumtoxinA has been shown to be as effective as topical nitrates, but with fewer adverse effects, including headache, and can be an alternative to surgery.[25, 36] Botulism toxin has not been shown to be an effective treatment when other medical therapies have failed.[37]

Topical analgesics

Topical lidocaine can be used as an anesthetic to help relieve pain associated with anal fissures. Clove oil has also been studied and shows some promise in providing analgesia.[38]

Surgical Treatment of Chronic Anal Fissures

Chronic anal fissures frequently require surgical treatment.[15] Surgical procedures may involve lateral internal sphincterotomy (LIS), anal dilation, or fissurectomy.

LIS is considered the treatment of choice for chronic anal fissure and can be performed either opened or closed.[17, 39, 40] It reduces the hypertonia of the internal anal sphincter, increases anodermal blood flow, decreases pain, and allows the fissure to heal. However, traditional LIS has been associated with relatively high rates of incontinence.

A systematic review and meta-analysis of the literature (inception to January 2017) that compared the efficacy of LIS with that of anal advancement flap (AAF) in 4 trials involving 300 patients found a significantly lower rate of anal incontinence than that of LIS, but wound complications and rate of unhealed fissures were comparable.[41]

Other surgical techniques have been described, including a more tailored approach, which showed lower rates of complications but higher rates of treatment failure.[42, 43, 44] LIS has been shown to have a higher rate of cure than anal dilation. Data for subcutaneous fissurectomy with anal advancement flap are limited, but promising.[17, 45]

Success has been reported for chronic anal fissure with associated anal fistula using a combined approach of  fistulotomy and injection of botulinum A toxin.[46] A retrospective, observational study (2013-2016) of 20 patients with fissure-fistula treated with fistulotomy and botulinum toxin A found resolution of symptoms in all patients who attended follow-up appointments (mean, 10.5 weeks), with no reports of incontinence and no further operation required.[46]

Surgical Treatment of Anal Fistulas

For simple anal fistulas, fistulotomy with or without marsupialization is recommended.[21] In the presence of an abscess with anal fistula, incision and drainage along with fistulotomy may be considered. This is associated with decreased recurrence (relative risk, 0.17; 95% confidence interval, 0.09-0.32; P< .001) but increased risk of continence disturbance.[47] Fibrin glue has also been studied, with the advantage of less risk of incontinence. However, success rates have been reported lower than those for fistulotomy (41.7%).

For complex fistulas, debridement and fibrin glue or fistula plug may be used. Success rates for fibrin glue range from 10-67%. Although it has a relatively low success rate, recent guidelines suggest that fibrin glue may be used as first-line therapy.[21] Likewise, variable success has been reported with fistula plugs. One small trial described a success rate of 72.7% with the use of the Gore Bio-A fistula plug.[48] Endoanal advancement flaps also have variable success rates for the treatment of complex fistulas.

Ligation of intersphincteric fistula tract (LIFT) has also been described, with long-term success rates (> 12 months) of 62%.[49] In this small study, fistula tract lengths greater than 3 cm were noted to have a higher rate of failure with LIFT (odds ratio, 0.55; 95% confidence interval, 0.34-0.88).

In a retrospective review of a prospectively collected database for evaluation of the healing rate after operations for anal fistulas in New England colorectal surgery practices, the healing rates of fistulotomy, advancement flap, and fistula plugs at 3 months were 94%, 60%, and 20%, respectively.[50] The healing rate of the ligation of intersphincteric fistula tract procedure at 3 months was 79%. Hospitals that performed more ligation of intersphincteric fistula tract procedures had higher healing rates at 3 months.[50]

In one retrospective study of 53 patients who underwent LIFT for anal fistula, of the 20 patients who had a failed LIFT at a median follow-up of 4 months, reoperation with placement of a seton followed by fistulotomy or rectal advancement flap appeared to resolve the fistula in 50% of these patients, with another nearly one third (31.7%) still undergoing therapy.[51]  The majority of the recurrent fistulas was transsphincteric (75%) (25% intersphincteric). 

Video-assisted anal fistula treatment (VAAFT) shows promise for safely and effectively managing perianal fistulas, regardless of comorbidity, underlying pathology, or type of fistula.[52, 53] Recurrence after VAAFT may be related to previous fistula surgery and the method of closure of the internal opening (eg, using staplers, after suturing, after advancement flap).[53]

In some cases, staged surgery is needed to repair an anal fistula.

 

Medication

Medication Summary

Medications may also be prescribed for anal fissures, such as topical nitrates, calcium channel blockers, and onabotulinumtoxinA injections, and are considered first-line therapy.[17] These medications reduce anal sphincter tone, which, in turn, increases anodermal blood flow.

Antibiotics may be necessary for the treatment of anal fistulas, especially if the patient presents with systemic symptoms. Postoperative prophylactic antibiotic therapy for 7-10 days (eg, ciprofloxacin, metronidazole) appears to be a key part of preventing anal fistulas after incision and drainage of perianal abscess.[54]

Laxatives, Bulk-Producing

Class Summary

Psyllium facilitates easier passage of stools.

Psyllium (Fiberall, Metamucil, Konsyl, Reguloid, Natural Fiber Therapy)

Psyllium promotes bowel evacuation by forming a viscous liquid and promoting peristalsis.

Vasodilators

Class Summary

Vasodilators that cause smooth muscle relaxation are used for relief of anal spasm.

Nitroglycerin rectal (Rectiv)

Organic nitrate is indicated for moderate to severe pain associated with chronic anal fissures. It elicits internal anal sphincter relaxation and reduces sphincter tone and resting intra-anal pressure.

Anxiolytics, Benzodiazepines

Class Summary

These agents may potentiate the effects of gamma-aminobutyric acid (GABA) and facilitate inhibitory GABA neurotransmission.

Diazepam (Valium, Diastat)

Diazepam is indicated for the relief of severe anal sphincter spasms.

Antibiotics

Class Summary

Antibiotic therapy must cover both aerobic and anaerobic gram-negative organisms.

Vancomycin

Vancomycin is a potent antibiotic that is directed against gram-positive organisms and is active against Enterococcus species. It is useful in the treatment of septicemia, enterocolitis, and skin-structure infections. Vancomycin is indicated for patients who are unable to receive or have not responded to penicillins and cephalosporins or for patients with resistant staphylococcus infections. Creatinine clearance measurements are used to adjust the dose in patients with renal impairment.

Metronidazole (Flagyl)

Metronidazole is active against various anaerobic bacteria and protozoa. It appears to be absorbed into cells. Intermediate metabolized compounds are formed and bind DNA and inhibit protein synthesis, causing cell death. The antimicrobial effect may be due to production of free radicals.

Ampicillin and sulbactam (Unasyn)

This drug combination of a beta-lactamase inhibitor with ampicillin interferes with bacterial cell wall synthesis during active replication, causing bactericidal activity against susceptible organisms.

Ticarcillin and clavulanate potassium (Timentin)

This drug combination of antipseudomonal penicillin plus a beta-lactamase inhibitor inhibits biosynthesis of cell wall mucopeptide and is effective during the stage of active growth. It provides coverage against most gram-positive, gram-negative, and anaerobic organisms.

Clindamycin (Cleocin)

Clindamycin is effective in the treatment of anaerobic bacteria. It has been shown to have superior effectiveness against streptococci and staphylococci. It continues to be effective against methicillin-resistant Staphylococcus aureus (MRSA).

Calcium Channel Blockers

Class Summary

Calcium channel blockers work by decreasing resting anal pressures. In a recent review, calcium channel blockers were shown to be as effective as topical nitrates. Oral and topical calcium channel blockers (diltiazem and nifedipine) have been shown to be effective treatment options for anal fissures.

Nifedipine (Nifediac CC, Adalat CC, Procardia, Procardia XL)

Nifedipine is the prototypical dihydropyridine. The topical form is preferred but must be compounded in the pharmacy.

Diltiazem (Cardizem, Cardizem CD, Cartia XT, Dilacor XR, Tiazac)

Diltiazem is a nondihydropyridine that has been reported to be effective. The topical form is preferred but must be compounded in the pharmacy.

Neuromuscular Blockers, Botulinum Toxins

Class Summary

OnabotulinumtoxinA is used typically to treat muscle hypertonia and cosmetic disorders. Typically, onabotulinumtoxinA is injected into the internal sphincter, reducing hypertonia. Various dosing schemes have been used, and it is typically injected on both sides of the anal fissure. OnabotulinumtoxinA has been shown to be as effective as topical nitrates, but with fewer adverse effects, including headache, and can be an alternative to surgery.

OnabotulinumtoxinA (BOTOX)

OnabotulinumtoxinA is used typically to treat muscle hypertonia and cosmetic disorders. Typically, onabotulinumtoxinA is injected into the internal sphincter, reducing hypertonia.

 

Questions & Answers

Overview

What is an anal fissure?

What are anal fistulas and how are they categorized?

What causes anal fissures?

What is the role blood flow in the pathogenesis of anal fissures?

What is the pathophysiology of anal fistulas?

What are the types of anal fistulas?

What is the epidemiology of anal fissures?

What is the prevalence of anal fistulas due to anorectal abscess?

What is the prognosis of anal fissures?

What is the prognosis of anal fistulas?

Presentation

Which history is characteristic of anal fissure?

What are symptoms of an anal fistula?

How is the physical exam for anal fistula or fissure performed?

What are the physical findings indicative of chronic fissures?

Which bidigital rectal exam findings indicate anal fistula?

What are complications of anal fissure?

What are complications of surgical intervention for an anal fissure?

What is a possible complication of chronic untreated anal fistulas?

DDX

What are the differential diagnoses for Anal Fistulas and Fissures?

Workup

How are anal fissures diagnosed?

How are anal fistulas diagnosed?

Treatment

What are the treatment options for anal fissures?

What is the WASH treatment for anal fissures?

Which medications are used to treat anal fissures?

What is the role of botulinum toxin in the treatment of anal fissures?

Which treatments for anal fissures are being investigated?

What is the role of surgery in the treatment of anal fissures?

What are the treatment options for anal fistulas?

What is the role of antibiotics in the treatment of anal fistulas?

What is the role of local injections in the treatment of anal fistulas associated with Crohn&#39;s disease?

What are guidelines for treating anal fistulas associated with Crohn&#39;s disease?

What is the role of calcium channel blockers in the treatment of anal fissures?

What is the role of topical nitrates in the treatment of anal fissures?

What is the dosing for topical nitrates to treat anal fissures?

What is the efficacy of botulinum toxin A (Dysport for the treatment of chronic anal fissures?

What is the role of OnabotulinumtoxinA in the treatment of anal fissures?

What is the role of topical analgesics in the treatment of anal fissures?

What is the role of surgery in the treatment of anal fissures?

What is the surgery of choice for chronic anal fissures?

What are alternative techniques for surgical treatment of chronic anal fissures?

What are the surgical options for simple anal fistulas?

What are the surgical options for complex anal fistulas?

What is the role of ligation of intersphincteric fistula tract (LIFT) in the treatment of anal fistulas?

What is the efficacy of surgery of anal fistulas?

What is the efficacy of ligation of intersphincteric fistula tract (LIFT) in the treatment of anal fistulas?

What is video-assisted anal fistula treatment (VAAFT)?

Medications

Which medications are used in the treatment of anal fissures and anal fistulas?

Which medications in the drug class Neuromuscular Blockers, Botulinum Toxins are used in the treatment of Anal Fistulas and Fissures?

Which medications in the drug class Calcium Channel Blockers are used in the treatment of Anal Fistulas and Fissures?

Which medications in the drug class Antibiotics are used in the treatment of Anal Fistulas and Fissures?

Which medications in the drug class Anxiolytics, Benzodiazepines are used in the treatment of Anal Fistulas and Fissures?

Which medications in the drug class Vasodilators are used in the treatment of Anal Fistulas and Fissures?

Which medications in the drug class Laxatives, Bulk-Producing are used in the treatment of Anal Fistulas and Fissures?