Therapeutic effects of different doses of botulinum toxin in chronic anal fissure

Randomized prospective controlled trial of lateral internal sphincterotomy versus injection of botulinum toxin for the treatment of idiopathic fissure in ano

BACKGROUND

Chronic anal fissure is a significant cause of morbidity. Internal sphincterotomy has long been the operative treatment of choice. Concerns remain, however, on its effects on continence. Botulinum toxin has been used as an agent for chemical sphincterotomy, causing temporary alleviation of sphincter spasm and allowing the fissure to heal. The aim of the present study was to compare the results of sphincterotomy to botulinum toxin.

METHODS

The study was designed as a randomized controlled trial. All adult patients over the age of 18 with chronic idiopathic fissure in ano who had failed conservative treatment were included in the trial. Patients were randomized to receive either Botox or sphincterotomy. Pain, healing of fissure and continence scores were the outcomes assessed.

RESULTS

A total of 38 patients were studied. Seventeen patients were randomized to receive Botox and 21, sphincterotomy. Patients in the Botox group were found to have significantly higher 2-week pain scores and reoperation rates, and poor healing. Continence scores were not significantly different in the two groups.

CONCLUSION

Sphincterotomy gives better results than Botox in the treatment of fissure. Botox, however, is safe with no complications and no detriment to continence and could be used in certain situations.

Prospective manometric assessment of botulinum toxin and its correlation with healing of chronic anal fissure

INTRODUCTION

The efficacy and pharmacokinetics of botulinum toxin for chronic anal fissure continues to be debated. Addressing both issues we prospectively assessed the manometric impact of botulinum toxin on internal anal sphincter pressure, correlating this impact with chronic anal fissure healing.

METHODS

Sixty patients with chronic fissures were assessed. Fifty-seven patients had a total of 20 units of botulinum toxin injected into the intersphincteric groove at four o'clock and eight o'clock. Patients were prospectively assessed with a linear analog pain score, bleeding score, clinical fissure score, modified St. Mark's continence score, and anorectal manometry. Each parameter was reassessed two weeks following treatment and again at three months.

RESULTS

Fifty-six patients (30 female), median age 43 (range, 17-80) years, were followed for a median of five (range, 3-15) months with fissure healing assessed 12 weeks after treatment. Physical healing and symptom control were dependent on the baseline maximum anal resting pressure and baseline fissure score (P = 0.003, P = 0.009, respectively). Although maximum anal resting pressure fell by 17 (mean, range, 0-71) percent, pressure reduction did not correlate with clinical outcome (P > 0.2). Seventeen patients reported a mean 17 percent increase in continence score. There was no correlation between deterioration in continence and baseline or subsequent reduction in maximum anal resting pressure.

CONCLUSION

Patients with Grade 1 lower-pressure fissures are more likely to heal following treatment with 20 units of botulinum toxin. Healing does not appear to be dependent on a reduction in maximum anal resting pressure.

Tratamiento de la fisura anal crónica

Chronic anal fissure is a common benign anorectal problem in Western countries that substantially impairs the patient's life. Consequently, a rapid and effective solution is required. We reviewed the various treatments for chronic anal fissure described in the literature, with the aim of establishing a therapeutic protocol. We recommend surgical sphincterotomy (preferably open or closed lateral sphincterotomy) as the first therapeutic approach in patients with chronic anal fissure. However, we prefer the use of chemical sphincterotomy (preferably botulinum toxin) in patients aged more than 50 years old and in those with previous incontinence, risk factors for incontinence (previous anal surgery, multiple vaginal births, diabetes, inflammatory bowel disease, etc.), or without anal hypertonia, despite the higher recurrence rate with medical treatments, since this procedure avoids the greater risk of residual incontinence described in the literature with surgical sphincterotomy in this group of patients.

[Manometric factors associated with recurrence in botulinum toxin treatment for chronic anal fissure]

INTRODUCTION AND AIM

To evaluate the effectiveness of botulinum toxin in the treatment of chronic anal fissure after long-term follow-up and establish the manometric factors related to recurrence.

PATIENTS AND METHOD

We performed a prospective study in 50 consecutive patients with chronic anal fissure who were treated with 25 U botulinum toxin injected into the internal sphincter. Clinical and manometric parameters were recorded until the fourth year of follow-up.

RESULTS

There was a tendency to progressive recurrence over time (54% at 4 years) associated with manometric factors indicating hyperexcitability of the internal anal sphincter (persistently elevated mean resting pressure, percentage of time with slow waves, and number of patients or percentage of time with ultra-slow waves after treatment).

CONCLUSIONS

Treatment of chronic anal fissure with botulinum toxin leads to long-term cure in less than 50% of patients. In patients with manometric factors related to recurrence, this treatment is insufficient for definitive cure.

Surgical versus chemical (botulinum toxin) sphincterotomy for chronic anal fissure: long-term results of a prospective randomized clinical and manometric study

BACKGROUND

The aim of this prospective randomized trial was to compare the effectiveness and morbidity of surgical versus chemical sphincterotomy in the treatment of chronic anal fissure after a 3-year follow-up.

METHODS

Eighty patients with chronic anal fissure were treated by whether open lateral internal sphincterotomy (group 1) or chemical sphincterotomy with 25 U botulinum toxin injected into the internal sphincter (group 2). Clinical and manometric results were analyzed.

RESULTS

Overall healing was 92.5% in the open sphincterotomy group and 45% in the toxin botulinum group (P<.001). There is a group of patients with clinical (duration of disease >12 months and presence of a sentinel pile before treatment) and manometric factors (persistently elevated mean resting pressure, % of time presence of slow waves, and number of patients or the time presence ultra slow waves after treatment) associated with a higher recurrence of anal fissure. The final percentage of incontinence was 5% in the open sphincterotomy group and 0% in the botulinum toxin group (P>.05).

CONCLUSION

We recommend surgical sphincterotomy as the first therapeutic approach in patients with clinical and manometric factors of recurrence. We prefer the use of botulinum toxin in patients older than 50 years or with risk factors for incontinence, despite the higher rate of recurrence, since it avoids the greater risk of incontinence in the surgical group.

Long-term results of botulinum toxin for the treatment of chronic anal fissure: prospective clinical and manometric study

BACKGROUND

The aim of this prospective trial was to analyse the effectiveness and morbidity of chemical sphincterotomy in the treatment of chronic anal fissure after a 3-year follow-up.

METHODS

One hundred consecutive patients with chronic anal fissures were treated by chemical sphincterotomy with 25 U botulinum toxin injected into the internal sphincter. Clinical and manometric results were recorded.

RESULTS

No major complications were found; initial incontinence at the 2-month review (6%) spontaneously reversed at 6 months. There was a tendency of progressive recurrence over time, with an overall healing after 3 years of 47%. We found a group of patients with clinical (symptoms longer than 12 months and presence of a sentinel pile before treatment) and manometric factors (persistently elevated mean resting pressure, percentage of time with slow waves, and number of patients or percentage of time with ultra slow waves after treatment) associated with a higher recurrence of anal fissures.

CONCLUSION

Since it avoids the greater risk of incontinence associated with surgical sphincterotomy, we recommend the use of botulinum toxin as the first therapeutic approach for patients with chronic anal fissure and risk factors for incontinence; despite the higher rate of recurrence associated with this treatment. In patients with factors related to recurrence, re-injection with higher doses of botulinum toxin or complementary medical-surgical treatment should be considered.

Gonyautoxin: new treatment for healing acute and chronic anal fissures

PURPOSE

The mayor symptoms of chronic anal fissure are permanent pain, intense pain during defecation that lasts for hours, blood in the stools, and sphincter cramps. It is subsequent to formation of fibrosis infiltrate that leads to an increased anal tone with poor healing tendency. This vicious circle leads to fissure recurrence and chronicity. This study was designed to show the efficacy of gonyautoxin infiltration in healing patients with anal fissures.

METHODS

Gonyautoxin is a paralyzing phytotoxin produced by dinoflagellates. Fifty recruited patients received clinical examination, including proctoscopy and questionnaire to evaluate the symptoms. Anorectal manometries were performed before and after toxin injection. Doses of 100 units of gonyautoxin in a volume of 1 ml were infiltrated into both sides of the anal fissure in the internal anal sphincter.

RESULTS

Total remission of acute and chronic anal fissures were achieved within 15 and 28 days respectively. Ninety-eight percent of the patients healed before 28 days with a mean time healing of 17.6 +/- 9 days. Only one relapsed during 14 months of follow-up. Neither fecal incontinence nor other side effects were observed. All patients showed immediate sphincter relaxation. The maximum anal resting pressures recorded after two minutes decreased to 56.2 +/- 12.5 percent of baseline.

CONCLUSIONS

Gonyautoxin breaks the vicious circle of pain and spasm that leads to anal fissure. This study proposes gonyautoxin anal sphincter infiltration as safe and effective alternative therapeutic approach to conservative, surgical, and botulinum toxin therapies for anal fissures.

[Botulinum toxin A in the treatment of anal fissure]

BACKGROUND

This paper presents our first experience in the treatment of primary anal fissure by injection of botulinum A toxin into the internal sphincter.

METHODS

The study group of the retrospective study included 12 outpatients (8 females and 4 males), mean age 42 (range 18-60). During the period 2000-2003, after unsuccessful conservative treatment, patients were treated with the injections of botulinum A toxin, 100 units on both sides of the anal fissure laterally into the internal anal sphincter (50 units on either side). The patients were clinically evaluated 3, 7, and 30 days, and 3 and 6 months after the treatment.

RESULTS

Three fissures had healed after a month, and seven after 3 months. Two remained unhealed, but asymptomatic. There was no incontinence of flatus or faeces after 3 months of the treatment. After temporary healing, two fissures relapsed after 6 months, and these patients had the adequate tonus of the anal sphincter muscles. Except for the temporary incontinence, there were neither other side-effects, nor serious complications.

CONCLUSION

Injection of botulinum A toxin achieved good results in the treatment of anal fissure. The appropriate use makes this method safe as an alternative to surgical treatment of anal fissure.

Treating chronic anal fissure with botulinum neurotoxin

Recent reports confirm that the management of chronic anal fissure has undergone extensive re-evaluation during the past few years. This rejuvenation of interest is attributable to the application of neurochemical treatment, which has contributed to the tendency to treat the disease on an outpatient basis. The use of botulinum neurotoxin seems to be a promising and safe approach for the treatment of chronic anal fissure, particularly in patients at high risk for incontinence. Indeed, botulinum neurotoxin has been successfully used selectively to weaken the internal anal sphincter as a treatment for chronic anal fissure. It is also more efficacious than nitrate therapy, and is not related to the patient's willingness to complete treatment.

Noncosmetic uses of botulinum toxin

In conclusion, botulinum toxin usage over the past 2 to 3 decades has expanded exponentially. Almost every discipline in medicine has found some therapeutic use for this toxin. Botulinum toxin has been shown to be safe, effective, and relatively easy to administer with proper training.

Botulinum neurotoxin to treat chronic anal fissure: results of a randomized "Botox vs. Dysport" controlled trial

BACKGROUND

Botulinum neurotoxin induces healing in patients with idiopathic fissure. The optimal dosage is not well established.

AIM

To compare the efficacy and tolerability of two different formulations of type A botulinum neurotoxin, and to provide more evidence with regard to the choice of dosage regimens.

METHODS

Symptomatic adults with chronic anal fissure were enrolled in a randomized study. The outcome of each group was evaluated clinically, and by comparing the pressure of the anal sphincters before and after treatment.

RESULTS

Fifty patients received injections of 50 units of Botox formulation (group I), and 50 patients received injections of 150 units of Dysport toxin (group II). One month after injection, 11 patients in group I and eight in group II had mild incontinence of flatus. At the 2-month evaluation point, 46 patients in group I and 47 patients in group II had a healing scar. In group I patients, the mean resting anal pressure was 41.8% lower, and the maximum voluntary squeeze pressure was 20.2% lower, than the baseline value. In group II patients, the resting anal pressure and maximum voluntary squeeze pressure were 60.0 +/- 12.0 mmHg and 71.0 +/- 30.0 mmHg, respectively. There were no relapses during an average of about 21 months of follow-up.

CONCLUSIONS

Botulinum neurotoxin may be considered an effective treatment in patients with chronic anal fissure. The efficacy and tolerability of the two different formulations of botulinum neurotoxin were indistinguishable.

Treatment with botulinum neurotoxin of gastrointestinal smooth muscles and sphincters spasms

Local injections of botulinum neurotoxin are now considered an efficacious treatment for neurological and non-neurological conditions. One of the most recent achievements in the field is the observation that botulinum neurotoxin provides benefit in diseases of the gastrointestinal tract. Botulinum neurotoxin inhibits contraction of gastrointestinal smooth muscles and sphincters; it has also been shown that the neurotoxin blocks cholinergic nerve endings in the autonomic nervous system, but it does not block nonadrenergic responses mediated by nitric oxide. This aspect has further promoted the interest to use botulinum neurotoxin as a treatment for overactive smooth muscles, such as the anal sphincters to treat anal fissure and outlet-type constipation, or the lower esophageal sphincter to treat esophageal achalasia. Knowledge of the anatomical and functional organization of innervation of the gastrointestinal tract is a prerequisite to understanding many features of botulinum neurotoxin action on the gut and the effects of injections placed into specific sphincters. This review presents current data on the use of botulinum neurotoxin to treat diseases of the gastrointestinal tract and summarizes recent knowledge on the pathogenesis of disorders of the gut due to a dysfunction of the enteric nervous system.

Noncosmetic uses of botulinum toxin

Since the introduction of botulinum toxin (BTX) as a therapeutic tool in the 1970s, the number of uses for this substance has increased exponentially. BTX's mechanism of action involves degrading the SNARE proteins blockading the release of acetylcholine into the neuromuscular junction. In many body systems, decrease of contractility, strength, and tension of certain muscle groups result in improved clinical outcomes. Applications now include cosmetic, gastroenterologic, otolaryngologic, genitourinary, neurologic, and dermatologic uses. In fact, BTX can be considered as a potential treatment in any situation involving inappropriate or exaggerated muscle contraction. Currently, the FDA has approved BTX-A (Botox) for treating glabellar lines, blepharospasm, strabismus, hemifacial spasm, cervical dystonia, and spasticity. With the addition of cosmetic applications to the FDA's approval list, the use of BTX has increased dramatically.

Anal fissure: the changing management of a surgical condition

BACKGROUND

Chronic anal fissure is a common benign disorder that causes severe, sharp anal pain during defaecation. Fissures are generally associated with raised resting anal pressures, and treatments are aimed at reduction of these pressures. Surgical sphincterotomy is very successful at healing fissures but is associated with significant morbidity. Much work has gone into the development of new pharmacological agents that can promote healing of chronic anal fissures by production of a reversible chemical sphincterotomy, with the aim of avoiding long-term problems of incontinence.

METHODS

We review these recent innovations that have largely replaced surgery as first line treatment for chronic anal fissure.

CONCLUSIONS

Despite there being initial success with many of these pharmacological agents in the treatment of patients with chronic anal fissures, there are still some concerns about their use. In particular, the occurrence of side effects limits their use, and, unfortunately, they are not always effective at healing fissures. However, despite these drawbacks they remain excellent first-line options in the treatment of chronic anal fissures, and surgery should be offered only to patients who fail these therapies.

Mechanism of action of botulinum toxin on the internal anal sphincter

Background

Botulinum toxin is an effective treatment for anal fissure. Manometric studies support an apparent action of botulinum toxin on the internal anal sphincter (IAS). This aim of this study was to establish the underlying mechanism.

Methods

Porcine IAS strips were suspended in a superfusion organ bath and allowed to equilibrate. Electrical field stimulation (EFS) was applied with parameters that induced nitrergic relaxation followed by noradrenaline-mediated contraction. These responses were compared before and after addition of botulinum toxin.

Results

All strips developed myogenic tone, which was slightly increased following the addition of botulinum toxin. EFS-induced nitrergic relaxation was unaffected by toxin treatment. However, EFS-induced contraction was significantly reduced by toxin treatment. 1,1-Dimethyl-4-phenylpiperazinium iodide (DMPP), a nicotinic agonist, caused muscle strip contraction, which was blocked by guanethidine, implying the presence of sympathetic ganglia within the IAS. Botulinum toxin significantly attenuated DMPP-induced contraction.

Conclusion

In the treatment of anal fissure the major effect of botulinum toxin on the IAS is blockade of sympathetic (noradrenaline mediated) neural output. This is probably a postganglionic action, involving a reduction in noradrenaline release at the neuromuscular junction. Botulinum toxin has no significant effect on nitrergic transmission, which is probably not vesicular in nature.

Botulinum toxin injection inhibits myogenic tone and sympathetic nerve function in the porcine internal anal sphincter

OBJECTIVE

Botulinum toxin is an effective treatment for anal fissure, though there is a lack of agreement over the optimal site for its injection. This reflects our current ignorance of its mechanism, and whether it has any action on the nerves of the internal anal sphincter (IAS). This study set out to resolve this issue through use of a pig model.

MATERIALS AND METHODS

Eight pigs were studied in pairs: one of each pair received a botulinum toxin injection into the anal sphincter, whilst the other acted as its control. Manometry was performed every two weeks under anaesthesia. Pigs were slaughtered at between four and six weeks after injection and the properties of the IAS compared in vitro.

RESULTS

Whilst maximum anal resting pressure (MARP) increased slowly in control pigs during the experimental period, reflecting weight gain, a fall was observed in treated pigs. In vitro, IAS strips from control pigs generated 400 mg of spontaneous tone per gram of tissue (+/- 45; standard error), compared to 250 (+/- 25) mg/g tissue from treated pigs (P < 0.01). Electric Field Stimulation at 50 Hz produced 150 (+/- 22) mg contraction/gram tissue in IAS strips from control pigs compared to 53 (+/- 13) mg/g tissue in treated pigs (P < 0.0005). This contractile response was blocked by guanethidine.

CONCLUSION

Botulinum toxin has a significant action on the IAS. It reduces myogenic tone and contractile responses of this tissue to sympathetic nerve stimulation. Further studies are required to clarify its mechanism of action more precisely.

Review article: botulinum toxin in the therapy of gastrointestinal motility disorders

Since 1980, botulinum toxin has been employed for the treatment of various voluntary muscle spastic disorders in the fields of neurology and ophthalmology. More recently, botulinum toxin has been proved to be effective in the therapy of dyskinetic smooth muscle disorders of the gastrointestinal tract. Achalasia and anal fissure are the gastrointestinal disorders in which botulinum toxin therapy has been most extensively investigated. Botulinum toxin is the best treatment option for achalasia in patients whose condition makes them unfit for pneumatic dilation or surgery. In anal fissure, botulinum toxin is highly effective and may become the treatment of choice. In the future, botulinum toxin application in the gastrointestinal tract will be extended to many other gastrointestinal disorders, such as non-achalasic motor disorders of the oesophagus, dysfunction of Oddi's sphincter, achalasia of the internal anal sphincter and others. This article describes the mechanism of action, rationale of employment, indications and side-effects of botulinum toxin application in smooth muscle disorders of the gastrointestinal tract, and compares the results of different techniques of botulinum toxin therapeutic application.

[Digestive tract and botulinum toxin]

INTRODUCTION

the aim of this work was to check literature to assess botulinum toxin injection efficacy in gastrointestinal motor disorders with special emphasis on controlled clinical trials.

METHODS

literature was carried out with the Medline data bank.

RESULTS

seventy three articles in French and in English including a recent general review were retained. Comparative clinical trials only concerned achalasia and anal fissure. The other gastrointestinal motor disorders only gave rise to open non-controlled trials assessed on clinical end points.

DISCUSSION

this review of literature helps to determine usefulness and safety of Botulinum toxin injection in the treatment of esophageal achalasia and anal fissure. The main limitation is its brief duration of action. Studies concerning the others spastic motor disorders are based on unknown physiopathology and controlled trials are required to assess its efficacy.

CONCLUSION

botulinum toxin is increasingly used for gastrointestinal motor disorders with worthwhile results. Its efficacy has been yet established for only two disorders : it has a valuable palliative role in achalasia and may be curative for anal fissure.

Concepts in pathogenesis and treatment of chronic anal fissure--a review of the literature

OBJECTIVE

Chronic anal fissures are associated with a persistent hypertonia and spasm of the internal anal sphincter. Classic treatment is surgical sphincterotomy to reduce the anal tone and eliminate sphincteric spasm. However, concerns have been raised about the incidence of fecal incontinence after surgery. Therefore, pharmacological means to treat chronic anal fissures have been explored.

METHODS

We conducted a literature review on MEDLINE database.

RESULTS

All treatments address the anomaly of a high anal pressure. Several studies have investigated the effect of topical glyceryl trinitrate ointment. Healing rates range from 30% to 86%. Therapy is limited because of a high incidence of moderate to severe headaches in up to 84% of patients. Comparable results are observed after injection of botulinum toxin into the anal sphincter (43-96%). Minor incontinence for flatus and soiling has been reported in up to 12% of patients. Further pharmacological approaches including treatment via calcium channel blockade and treatment with alpha-adrenoceptor antagonists are still at a developmental stage.

CONCLUSIONS

Topical glyceryl trinitrate ointment and injection of botulinum toxin into the anal sphincter are advocated as the first-line treatment for chronic anal fissure. Lateral sphincterotomy should be offered to patients with relapse and therapeutic failure of prior pharmacological treatment.

New approaches to the treatment of anal fissure

According to Antropoli, pathologies of the anal canal are extremely common. About 30 to 40 percent of the population suffers from proctologic pathologies at least once in their lives. In most cases they are more annoying than dangerous. Anal fissure (AF) was recognized as a clinical entity in 1934. It is a longitudinal defect of the anal canal mucosa and anoderm extending usually from the dentate line to the external verge of the anal canal. This defect exposes the lower half or even most of the fibres of internal anal sphincter. AF is almost always accompanied by extensive tension of this muscle. Anal fissures affect all age groups but predominantly occur in the 3rd and 4th decades of life (2, 8, 23). Gathright states that fissure disease causes from 6 to 15% of office visits and 10% of operative procedures in a colorectal practice. The etiology of anal fissure has only been partially explained and remains controversial although spasm of the internal anal sphincter has been recognized to play a main role in the pathogenesis of this disease. Recent studies have cast new light on the pathogenesis of anal fissures.

Botulinum toxin A in anal fissures: a modified technique

BACKGROUND

Anal fissures are common and painful. Botulinum toxin A (BTXA) is considered to be the most potent non-surgical treatment; however, no attention has been paid to associated hyperhidrosis.

AIM

To compare traditional BTXA treatment of muscular spasticity in anal fissures with combined treatment of spasticity and focal hyperhidrosis of the anal fold and perianal skin.

SETTING

Outpatient department of a dermatological hospital.

PATIENTS AND METHODS

Ten patients with chronic anal fissures (of more than 6 months duration who failed to respond to conservative treatment and who had refused surgery) associated with focal hyperhidrosis as assessed by Minor's sweat test were investigated in an open, two-armed trial. Intramuscular injections of 20-25 U BTXA (Botox) were performed in group A (n = 5). In group B (n = 5) those injections were combined with intracutaneous injection of 30-50 U BTXA to treat focal hyperhidrosis. Mean follow-up was 5 months.

RESULTS

Five of five patients in group B but only two of five patients in group A experienced a complete remission despite the fact that relief of pain was evident in eight of 10 patients within 2 weeks. Patient satisfaction with treatment was high but slightly better in group B.

CONCLUSIONS

This open trial suggests that combined therapy of both muscular spasticity and focal hyperhidrosis may provide better results than intramuscular injections alone in anal fissure therapy with BTXA.

Side effects of botulinum toxin injection for benign anal disorders

BACKGROUND

Botulinum toxin A (BT-A) is a powerful biological toxin. Nevertheless, it has proved to be a remarkable therapeutic agent for the treatment of benign anal disorders. Higher doses of BT-A could change the outcome of treatment. It is not known whether doses of BT-A higher than 20 units of Botox (or corresponding doses of Dysport) are as safe for patients as lower doses of BT-A.

METHODS

The side effects of BT-A injections in the treatment of chronic anal fissure (105 patients) and functional outlet obstruction (34 patients) were analysed prospectively. The patients received at least 25 units of Botox or 150 units of Dysport.

RESULTS

The patients with chronic anal fissure complained of incontinence of flatus (one severe case and eight mild cases), incontinence of faeces (five mild cases), anal haematoma (five cases), flu-like syndrome (three cases), an acute inflammation of external anal varices (two cases), epididymitis (one case) and haemorrhoid prolapse (one case). Patients with anismus suffered from intertrigo (one case); the pain after injection lasted for 2-4 days (four cases). No life-threatening side effects after 181 injections of BT-A were observed. Most of the side effects were only transient symptoms. No significant interdependence between injection methods (injection into one or two sites) and the risk of side effects was found.

CONCLUSION

Treatment with BT-A is safe. Despite the application of higher doses of BT-A in the treatment of benign anal disorders so far, no severe side effects were observed.

Botulinum neurotoxin and other treatments for fissure-in-ano and pelvic floor disorders

BACKGROUND

The management of disorders of the lower gastrointestinal tract, such as chronic anal fissure and pelvic floor dysfunction, has undergone re-evaluation recently. To a large extent this is due to the advent of neurochemical treatments, such as botulinum neurotoxin injections and topical nitrate ointment.

METHODS AND RESULTS

This review presents, inter alia, current data on the use of botulinum neurotoxin to treat lower gastrointestinal tract diseases, such as chronic anal fissure for which it promotes healing and symptom relief in up to 70 per cent of cases. This agent has also been used selectively to weaken the external anal sphincter and puborectalis muscle in constipation and in Parkinson's disease. Symptomatic improvement can also be induced in anterior rectocele by botulinum neurotoxin injections.

CONCLUSION

Botulinum neurotoxin appears to be a safe therapy for anal fissure. It is more efficacious than nitrate application and does not require patient compliance to complete treatment. While it may also be a promising approach for the treatment of chronic constipation due to pelvic floor dysfunction, further investigation of its efficacy and safety in this role is needed before general usage can be advocated.

Long-term follow-up (42 months) of chronic anal fissure after healing with botulinum toxin

BACKGROUND & AIMS

Botulinum toxin is an effective treatment in idiopathic chronic anal fissure, but the long-term outcome after healing is not well documented. We analyzed the long-term outcome of patients in whom an anal fissure had healed after botulinum toxin injection and the factors contributing to recurrence.

METHODS

Fifty-seven patients who had completely healed 6 months after injection of botulinum toxin were reassessed every 6 months. The follow-up was 42 months in all patients. Clinical and manometric differences between the permanently healed and the relapsed group were statistically analyzed.

RESULTS

Four patients were lost to follow-up. A fissure recurrence was shown in 22 patients (41.5%). Statistical differences between the permanently healed and the relapsed group were detected when analyzing the anterior location of the fissure (6% vs. 45%), a longer duration of the disease (38% vs. 68%), the need for reinjection (26% vs. 59%), a higher total dose injected to achieve definitive healing (13% vs. 45%), and the percentage decrease of maximum squeeze pressure after injection (-28% vs. -13%; P < 0.05).

CONCLUSIONS

The late recurrence rate of chronic anal fissure is high when the effect of botulinum toxin disappears. The highest risk of recurrence is associated with anterior location of the anal fissure, prolonged illness, the need for reinjection and for high doses to achieve healing, and a lower decrease of maximum squeeze pressure after treatment.

Other noncosmetic uses of BOTOX

Botulinum toxin A has a wide variety of clinical applications, which are related by blockade of acetylcholine and often are related to abnormal muscle contractures. These applications include ocular disorders, disorders of the upper aerodigestive tract, dystonia and hemifacial spasm, cosmetic, gastrointestinal disorders, genitourinary disorders, management of pain, and use in autonomic nervous system disorders. Many of these diseases will be discussed with regard to their treatment with botulinum toxin compared to conventional treatments. Advantages and disadvantages of botulinum toxin use are delineated. General guidelines for adult and pediatric dosing will also be discussed.

Effectiveness of higher doses of botulinum toxin to induce healing in patients with chronic anal fissures

BACKGROUND

Botulinum toxin induces healing in patients with idiopathic anal fissures.

METHODS

One hundred-fifty patients with posterior anal fissures were treated with botulinum toxin injected in the internal anal sphincter on each side of the anterior midline. Subjects were randomized into 2 treatment groups based on the number of units of botulinum toxin injected. Patients in group I were treated with 20 units of botulinum toxin and, if the fissure persisted, were retreated with 30 units. Patients in group II were treated with 30 units and retreated with 50 units, if the fissure persisted.

RESULTS

The 2 groups were comparable in age, gender distribution, duration of symptoms, resting pressure, and maximum voluntary pressure at anorectal manometry. One month after the injection, examinations revealed complete healing in 55 patients (73%) from group I and 65 patients (87%) from group II (P =.04). Five patients from group II reported a mild incontinence of flatus that lasted 2 weeks after the treatment and disappeared spontaneously. The values of the resting anal pressure (P=.3) and the maximum voluntary pressure (P =.2) did not differ between the 2 groups. At 2 months' evaluation, a healing scar was found in 67 patients (89%) from group I and 72 patients (96%) from group II. A relapse of the fissure was observed in 6 patients (8%) from group I who had a healing scar at 1 month, and 2 other patients never healed. A persistent fissure was present in 3 patients from group II who had no other symptoms.

CONCLUSIONS

Botulinum toxin injected into the internal anal sphincter is effective in managing anal fissures and avoiding permanent complications. All patients were treated with the active drug and healed after 1 or 2 successive treatments. The results also confirm that higher doses account for a higher success rate, with little increase in complications or side effects, which is probably related to the diffusion of the toxin to the external sphincter.

Other noncosmetic uses of BOTOX

Botulinum toxin A has a wide variety of clinical applications, which are related by blockade of acetylcholine and often are related to abnormal muscle contractures. These applications include ocular disorders, disorders of the upper aerodigestive tract, dystonia and hemifacial spasm, cosmetic, gastrointestinal disorders, genitourinary disorders, management of pain, and use in autonomic nervous system disorders. Many of these diseases will be discussed with regard to their treatment with botulinum toxin compared to conventional treatments. Advantages and disadvantages of botulinum toxin use are delineated. General guidelines for adult and pediatric dosing will also be discussed.

The current use of botulinum toxin

Botulinum toxin is the most potent neurotoxin known, and has been in clinical use since the late 1970s. The toxin inhibits the release of acetylcholine from nerve terminals by inhibiting transport of the synaptic vesicles, thus causing functional denervation lasting up to 6 months. Our understanding of the mechanism of action of the toxin and the spectrum of diseases treatable with this agent continues to increase. Efficacy has been demonstrated in hemifacial spasm, dystonia, spasticity, hyperhidrosis and other conditions. Alternative serotypes are used in some centres, generally after the development of immunoresistance to the standard toxin (serotype A), and are likely to be in routine use in the near future. This paper reviews the history, pharmacology and current uses of botulinum toxin.

Pharmacotherapy with botulinum toxin: harnessing nature's most potent neurotoxin

Botulinum toxin (BTX), a potent biologic neurotoxin, commonly is associated with lethal outbreaks of food poisoning; however, it also plays a role as a therapeutic agent. Since the 1970s physicians have investigated BTX therapy in patients with neurologic disorders. The number of applications greatly expanded over the years to include certain focal dystonias (blepharospasm, torticollis, laryngeal dystonias, writer's cramp), strabismus, and a wide variety of other indications (gastrointestinal disorders, cosmetic wrinkle correction, spasticity, hyperhidrosis). BTX's safety and efficacy are reviewed.

Anorectal Disease

Most symptomatic internal hemorrhoids, grade 1 through 3, can be treated successfully with office-based procedures. Anorectal suppurative diseases must be treated surgically. Control of sepsis with subsequent fistula surgery as necessary is the goal. New nonoperative methods of anal fissure therapy are directed at reducing anal sphincter pressures. These methods have shown significant reduction in the need for sphincterotomy--a proven surgical technique with some risk of impaired continence. Surgery, using an advancement flap and partial internal sphincterotomy, remains the primary treatment for anal stenosis. Solitary rectal ulcer remains a difficult problem to manage medically and surgically. Multiple surgical techniques can effectively treat rectal prolapse. A minimal technique using Silastic wrap (Wright Medical Technologies; Arlington, TX), perineal resection (Altemeier procedure), and sigmoidectomy-rectopexy, or Ripstein suspension, has been the most favored method in selected patients.

Repeat botulin toxin injections in anal fissure: in patients with relapse and after insufficient effect of first treatment

Botulin toxin (BoTx) injections are an alternative treatment for uncomplicated anal fissures. Until recently, surgical management has been advocated for therapeutic failure of BoTx and recurrent fissures. In 20 patients with recurring anal fissure we examined the remission rate following a second course of botulin treatment. The dose was identical to the first treatment (5 units Botox). In group 2, 30 patients with therapeutic failure were treated with a higher dose of botulin toxin (10 units). In our patients with recurring fissure, 19 of 20 were pain-free within a week (95%). After three months, 14 patients (70%) had healed fissures. In group 2, 22 of 30 patients (73%) became pain-free within the first week following the second course of treatment. Two patients (7%) suffered from transient mild incontinence. Nineteen patients (63%) showed healed fissures three months following the second BoTx treatment. BoTx remains an effective treatment in recurring anal fissure as well as in patients with therapeutic failure of prior BoTx injections.