Treatment of anismus in intractable constipation with botulinum A toxin

Effectiveness and safety of botulinum neurotoxin for treating dyssynergic defecation: A systematic review and meta-analysis

Dyssynergic defecation (DD) is a common cause of chronic constipation. Owing to the lack of a comprehensive synthesis of available data on the effectiveness of botulinum neurotoxin (BoNT) for treating DD, we performed a systematic review and meta-analysis. We searched the PubMed, Embase, and Cochrane databases from inception to May 9, 2023. The outcomes comprise short-term and long-term symptom improvement, various anorectal function measurements, complications of fecal incontinence, and symptom improvement after repeated BoNT injections. A meta-analysis comparing BoNT injection with either surgery or biofeedback (BFB) therapy in treating DD was also conducted. Subgroup analysis and meta-regression were performed to identify possible moderator effects. We included five randomized controlled trials, seven prospective studies, and two retrospective observational studies. Short-term potential improvement in symptoms (event rate [ER], 66.4%; 95% CI, 0.513 to 0.783) was identified, but in the long-term (>12 months), this effect was decreased (ER, 38.2%; 95% CI, 0.267 to 0.511). Short-term improvements in objective anorectal physiologic parameters were also observed. Repeated BoNT injection was effective for patients with symptom recurrence. Subgroup analysis revealed enhanced long-term symptom improvement with high-dose BoNT, but this treatment also increased the risk of complications and recurrence compared with low doses. The effectiveness, complications, and recurrence of symptoms associated with BoNT injection and surgery did not differ significantly. BoNT injection significantly provided short-term symptom improvement but also heightened the risk of incontinence compared with BFB therapy. Our systematic review and meta-analysis indicated that BoNT could be beneficial for short-term symptom improvement in patients with DD, but this effect tended to decline 12 months after injection. Standardized BoNT intervention protocols remain warranted. Among the several treatments for DD, we concluded that BoNT injection is not inferior to other options considering its effectiveness in relieving symptoms, the associated complication development, and the risk of symptom recurrence.

The pluripotential evolution and journey of Botox (onabotulinumtoxinA)

Clinical use of onabotulinumtoxinA evolved based on strategic, hypothesis-driven applications, as well as serendipitous observations by physicians and patients. The success of onabotulinumtoxinA in blepharospasm and strabismus led to its study in other head and neck dystonias, followed by limb dystonia, tremor, and spasticity. The aesthetic use of onabotulinumtoxinA followed initial reports from patients of improved facial lines after injections for facial dystonias and hemifacial spasm. Although patients with dystonias and spasticity regularly reported that their local pain improved after injections, onabotulinumtoxinA was not systematically explored for chronic migraine until patients began reporting headache improvements following aesthetic injections. Clinicians began assessing onabotulinumtoxinA for facial sweating and hyperhidrosis based on its inhibition of acetylcholine from sympathetic cholinergic nerves. Yet another line of research grew out of injections for laryngeal dystonia, whereby clinicians began to explore other sphincters in the gastrointestinal tract and eventually to treatment of pelvic sphincters; many of these sphincters are innervated by autonomic nerves. Additional investigations in other autonomically mediated conditions were conducted, including overactive bladder and neurogenic detrusor overactivity, achalasia, obesity, and postoperative atrial fibrillation. The study of onabotulinumtoxinA for depression also grew out of the cosmetic experience and the observation that relaxing facial muscle contractions associated with negative emotions may improve mood. For approved indications, the safety profile of onabotulinumtoxinA has been demonstrated in the formal development programs and post-marketing reports. Over time, evidence has accumulated suggesting clinical manifestations of systemic effects, albeit uncommon, particularly with high doses and in vulnerable populations. Although onabotulinumtoxinA is approved for approximately 26 indications across multiple local regions, there are 15 primary indication uses that have been approved in most regions, including the United States, Europe, South America, and Asia. This review describes many uses for which AbbVie has not sought and/or received regulatory approval and are mentioned for historical context only.

Dyssynergic Defecation and Other Evacuation Disorders

Constipated patients are frequently referred to gastroenterologists for symptoms refractory to lifestyle modifications and laxatives. Dyssynergic defecation, the dyscoordination of rectoanal, abdominal, and pelvic floor muscles to facilitate defecation, is a major cause of refractory primary constipation. Understanding of the diagnosis, evaluation, and management of dyssynergic defecation and other evacuation disorders will allow providers to effectively manage these patients. This review focuses on the definition, pathophysiology, evaluation, and treatment of dyssynergic defecation and other evacuation disorders. Emerging treatments for these disorders include home biofeedback therapy for dyssynergic defecation and translumbosacral neuromodulation therapy for levator ani syndrome.

High Anal Canal Pressure and Rectal Washouts Contribute to the Decrease of Anal Basal Pressure After Botulinum Toxin Injections in Paediatric Patients With Chronic Constipation

INTRODUCTION

Chronic constipation can be treated by injecting botulinum toxin into the anal sphincter to decrease anal basal pressure. To assess the effect of botulinum toxin, we investigated the factors that contribute to changes in anal basal pressure after injection.

METHODS

This was a retrospective study conducted in a tertiary hospital in the Netherlands. We included children with chronic constipation treated with botulinum toxin injections and measured anal basal pressure before and after each injection. Multivariable linear regression analyses were used.

RESULTS

We investigated 30 cases with idiopathic constipation. Their median age was 20.5 (7.75-53.25) months. Anal basal pressure decreased after injection in 20 cases. The mean decrease of anal basal pressure after injection was 18.17 ± 35.22 mmHg. The anal basal pressure change was linearly correlated with preinjection pressure (R ² = 0.593, P < 0.001). A significant decrease of pressure was observed in patients with preinjection pressure > 70 mmHg. Preinjection anal basal pressure (β = -0.913, P < 0.001) and rectal washouts (β = -21.015, P = 0.007) contributed significantly to pressure changes. Changes in anal basal pressure were also significantly associated with patients' weights (β = 0.512, 95% CI, 0.011-1.013) and sex (β = 22.971, 95% CI, 9.205-36.736).

CONCLUSIONS

Botulinum toxin significantly decreases anal basal pressure when preinjection pressure is higher than 70 mmHg. In patients with severely elevated anal basal pressure, we recommend rectal washouts to promote the decrease of anal basal pressure.

Botulinum toxin type-A infiltration of the external anal sphincter to treat outlet constipation in motor incomplete spinal cord injury: pilot cohort study

BACKGROUND

Outlet constipation is a major problem in spinal cord injury (SCI) patients. We aimed to study the efficacy of external anal sphincter (EAS) infiltration with type-A botulinum toxin (BTX-A) in motor incomplete SCI patients with outlet constipation.

METHODS

Double blind, randomized, placebo controlled, comparative study in 16 motor incomplete SCI subjects. Patients were randomly assigned toreceive100 UI of BTX-A (n = 9) or physiologic serum infiltration (n = 7) in the EAS under electromyographic guidance. Outcome measures included a questionnaire for clinical bowel function evaluation, colonic transit time and anorectal manometry. All assessments were done at baseline, 1 and 3 months after treatment.

RESULTS

Fourteen patients completed the study. In the BTX-A group we observed an improvement of subjective perception of bowel function (p = 0.01), constipation (p = 0.02) and neurogenic bowel dysfunction score (p = 0.02). The anorectal manometry revealed are duction of EAS voluntary contraction pressure (p = 0.01). No changes were observed in the placebo group. No significant side effects were observed in none of the groups.

CONCLUSION

BTX-A infiltration of the EAS is a safe technique that in motor incomplete SCI, decreases the EAS contraction and the anal canal pressure during straining, and improves outlet constipation symptoms. Future studies in larger populations are needed.

Botulinum toxin type A for the treatment of dyssynergic defaecation in adults: a systematic review

AIM

Dyssynergic defaecation (DD) is characterized by inappropriate coordination of the pelvic floor muscles during defaecation, resulting in impaired stool expulsion. The mainstay of treatment is biofeedback and alternative therapies are limited in those who do not respond. This systematic review evaluated botulinum toxin type A injection (BTXA) as a treatment option for dyssynergia.

METHODS

PubMed, Embase and Cochrane Central Register of Controlled Trials were searched for studies evaluating adult patients with DD treated with BTXA injection into the puborectalis and/or external anal sphincter. All study designs, except case reports, were included in the review with no language restriction. Studies limited to patients with specific neurological diagnoses or with a follow-up period under 1 month were excluded. Study selection, assessment and data extraction were performed by two reviewers and results were synthesized narratively.

RESULTS

Eleven studies (three randomized control trials) involving 248 participants were included. All studies used the transanal approach to deliver the injection, most commonly at the 3 and 9 o'clock positions using digital palpation for guidance. The most commonly used patient position was left lateral, and most studies did not use any anaesthesia. The dose of BTXA varied (Botox 12-100 units, Dysport 100-500 units), and outcomes measured were heterogeneous (global rating ± up to five investigations). Symptomatic improvement varied between 29.2% and 100% and adverse effects occurred in 0% to 70%.

CONCLUSION

The evidence to support using BTXA for DD is poor and only covers a transanal approach. Future studies should redress these limitations: heterogeneity of design, dose and outcome measures.

Gastrointestinal Uses of Botulinum Toxin

Botulinum toxin (BT), one of the most powerful inhibitors that prevents the release of acetylcholine from nerve endings, represents an alternative therapeutic approach for "spastic" disorders of the gastrointestinal tract such as achalasia, gastroparesis, sphincter of Oddi dysfunction, chronic anal fissures, and pelvic floor dyssynergia.BT has proven to be safe and this allows it to be a valid alternative in patients at high risk of invasive procedures but long-term efficacy in many disorders has not been observed, primarily due to its relatively short duration of action. Administration of BT has a low rate of adverse reactions and complications. However, not all patients respond to BT therapy, and large randomized controlled trials are lacking for many conditions commonly treated with BT.The local injection of BT in some conditions becomes a useful tool to decide to switch to more invasive therapies. Since 1980, the toxin has rapidly transformed from lethal poison to a safe therapeutic agent, with a significant impact on the quality of life.

The Role of Botox in Colorectal Disorders

PURPOSE OF REVIEW

To overview the current medical literature on the efficacy of botulism toxin treatment (BTX-A) for lower gastrointestinal disorders (GIT).

RECENT FINDINGS

BTX-A was found to have a short-term efficacy for the treatment of dyssynergic defecation. Surgical treatment was found to be more effective than BTX-A for the healing of chronic anal fissures, and BTX-A can be considered when surgery is undesirable. Data regarding the effects of BTX-A injection for the treatment of chronic anal pain is limited. Beneficial effects were observed only in a minority of patients. BTX-A treatment was found to be effective for the treatment of obstructive symptoms after surgery for Hirsprung's disease as well as for the treatment of internal anal sphincter achalasia. BTX-A treatment has a short-term efficacy and is safe. Further research is still needed in order to establish the exact place of BTX-A treatment of lower GIT disorders.

Management of constipation in patients with Parkinson's disease

A considerable body of research has recently emerged around nonmotor symptoms in Parkinson's disease (PD) and their substantial impact on patients' well-being. A prominent example is constipation which occurs in up to two thirds of all PD-patients thereby effecting psychological and social distress and consequently reducing quality of life. Despite the significant clinical relevance of constipation, unfortunately little knowledge exists on effective treatments. Therefore this systematic review aims at providing a synopsis on clinical effects and safety of available treatment options for constipation in PD. For this purpose, three electronic databases (MEDLINE, EMBASE, PsycINFO) were searched for experimental and quasi-experimental studies investigating the efficacy/effectiveness of interventions in the management of PD-associated constipation. Besides, adverse events were analyzed as secondary outcome. In total, 18 publications were identified involving 15 different interventions, of which none can be attributed sufficient evidence to derive strong recommendations. Nevertheless, some evidence indicates that dietetic interventions with probiotics and prebiotics may reduce symptom burden while providing a very favorable side-effects profile. Furthermore, the use of lubiprostone, macrogol and in the specific case of isolated or prominent outlet obstruction constipation injections of botulinum neurotoxin A into the puborectal muscles may as well be moderately supported. In summary, too little attention has been paid to treatment options for constipation in PD leaving abundant room for further research addressing this topic.

Increased anal basal pressure in chronic anal fissures may be caused by overreaction of the anal-external sphincter continence reflex

Chronic anal fissure is a painful disorder caused by linear ulcers in the distal anal mucosa. Even though it counts as one of the most common benign anorectal disorders, its precise etiology and pathophysiology remains unclear. Current thinking is that anal fissures are caused by anal trauma and pain, which leads to internal anal sphincter hypertonia. Increased anal basal pressure leads to diminished anodermal blood flow and local ischemia, which delays healing and leads to chronic anal fissure. The current treatment of choice for chronic anal fissure is either lateral internal sphincterotomy or botulinum toxin injections. In contrast to current thinking, we hypothesize that the external, rather than the internal, anal sphincter is responsible for increased anal basal pressure in patients suffering from chronic anal fissure. We think that damage to the anal mucosa leads to hypersensitivity of the contact receptors of the anal-external sphincter continence reflex, resulting in overreaction of the reflex. Overreaction causes spasm of the external anal sphincter. This in turn leads to increased anal basal pressure, diminished anodermal blood flow, and ischemia. Ischemia, finally, prevents the anal fissure from healing. Our hypothesis is supported by two findings. The first concerned a chronic anal fissure patient with increased anal basal pressure (170mmHg) who had undergone lateral sphincterotomy. Directly after the operation, while the submucosal anesthetic was still active, basal anal pressure decreased to 80mmHg. Seven hours after the operation, when the anesthetic had completely worn off, basal anal pressure increased again to 125mmHg, even though the internal anal sphincter could no longer be responsible for the increase. Second, in contrast to previous studies, recent studies demonstrated that botulinum toxin influences external anal sphincter activity and, because it is a striated muscle relaxant, it seems reasonable to presume that it affects the striated external anal sphincter, rather than the smooth internal anal sphincter. If our hypothesis is proved correct, the treatment option of lateral internal sphincterotomy should be abandoned in patients suffering from chronic anal fissures, since it fails to eliminate the cause of high anal basal pressure. Additionally, lateral internal sphincterotomy may cause damage to the anal-external sphincter continence reflex, resulting in fecal incontinence. Instead, higher doses of botulinum toxin should be administered to those patients suffering from chronic anal fissure who appeared unresponsive to lower doses.

Efficacy and safety of botulinum toxin in treatment of anismus: A systematic review

AIM: To evaluate the efficacy and safety of botulinum toxin type A (BTX-A) in the management of patients with anismus.

METHODS: An organized search of published literature was conducted using electronic databases including: PubMed/MEDLINE, and Cochrane Central Register of Controlled Trials, also an internet-based search using “Google Scholar” service was conducted. Both comparative and observational studies were included. We excluded irrelevant articles, editorials, case reports, reviews, and meta-analyses. The studies that followed the patients less than 6 mo were excluded. Variables collected were demographic data of the patients, technique of BTX-A injection and number of sessions, short-term and long-term clinical improvement, post-injection changes in electromyography (EMG), defecography, manometry, and balloon expulsion test, and complications recorded after BTX-A injection.

RESULTS: Seven studies comprising 189 patients were included in the review. The median age of the patients was 41.2 years and female-to-male ratio was 1.3:1. The median dose of BTX-A injected per procedure was 100 IU (range, 20-100 IU). Lateral injection was done in five trails and combined lateral and posterior injections in two trials. Three studies used endorectal ultrasonography-guided technique, one study used EMG-guided technique, whereas the remaining three studies used manual palpation with the index finger. The median percentage of patients who reported initial improvement of symptoms was 77.4% (range 37.5%-86.7%), this percentage declined to a median of 46% (range 25%-100%) at 4 mo after injection of BTX-A. Rates of improvement evaluated by balloon expulsion test, EMG, and defecography ranged between (37.5%-80%), (54%-86.7%), and (25%-86.6%), respectively. Fourteen (7.4%) patients developed complications after injection of BTX-A. Complication rates across the studies ranged from 0% to 22.6%.

CONCLUSION: Initial satisfactory improvement of symptoms after BTX-A injection remarkably deteriorated after 3 mo of the procedure. However, repeated injection may provide better sustained results with no additional morbidities. Further analysis of more patients is necessary to conclude the safety of BTX-A for the treatment of anismus.

Diagnosis and Treatment of Dyssynergic Defecation

Dyssynergic defecation is common and affects up to one half of patients with chronic constipation. This acquired behavioral problem is due to the inability to coordinate the abdominal and pelvic floor muscles to evacuate stools. A detailed history, prospective stool diaries, and a careful digital rectal examination will not only identify the nature of bowel dysfunction, but also raise the index of suspicion for this evacuation disorder. Anorectal physiology tests and balloon expulsion test are essential for a diagnosis. Newer techniques such as high-resolution manometry and magnetic resonance defecography can provide mechanistic insights. Recently, randomized controlled trials have shown that biofeedback therapy is more effective than laxatives and other modalities, both in the short term and long term, without side effects. Also, symptom improvements correlated with changes in underlying pathophysiology. Biofeedback therapy has been recommended as the first-line of treatment for dyssynergic defecation. Here, we provide an overview of the burden of illness and pathophysiology of dyssynergic defecation, and how to diagnose and treat this condition with biofeedback therapy.

Diagnosis and management of chronic constipation in adults

Constipation is a heterogeneous, polysymptomatic, multifactorial disease. Acute or transient constipation can be due to changes in diet, travel or stress, and secondary constipation can result from drug treatment, neurological or metabolic conditions or, rarely, colon cancer. A diagnosis of primary chronic constipation is made after exclusion of secondary causes of constipation and encompasses several overlapping subtypes. Slow-transit constipation is characterized by prolonged colonic transit in the absence of pelvic floor dysfunction. This subtype of constipation can be identified using either the radio-opaque marker test or wireless motility capsule test, and is best treated with laxatives such as polyethylene glycol or newer agents such as linaclotide or lubiprostone. If unsuccessful, subspecialist referral should be considered. Dyssynergic defecation results from impaired coordination of rectoanal and pelvic floor muscles, and causes difficulty with defecation. The condition can be identified using anorectal manometry and balloon expulsion tests and is best managed with biofeedback therapy. Opioid-induced constipation is an emerging entity, and several drugs including naloxegol, methylnaltrexone and lubiprostone are approved for its treatment. In this Review, we provide an overview of the burden and pathophysiology of chronic constipation, as well as a detailed discussion of the available diagnostic tools and treatment options.

Defecating Disorders: A Common Cause of Constipation in Women

Defecating disorders are a common and complex problem. There are a range of anatomical and functional bowel abnormalities that can lead to this condition. Treatment is difficult and needs a multidisciplinary approach. First line treatment for defecating disorders is conservative. For those that fail conservative treatment, some may respond to surgical therapy but with variable results. The aim of this review is to offer an overview of defecating disorders as well as provide an algorithm on how to diagnose and treat them with the help of a multidisciplinary and multimodal approach.

Treatment of gastrointestinal sphincters spasms with botulinum toxin A

Botulinum toxin A inhibits neuromuscular transmission. It has become a drug with many indications. The range of clinical applications has grown to encompass several neurological and non-neurological conditions. One of the most recent achievements in the field is the observation that botulinum toxin A provides benefit in diseases of the gastrointestinal tract. Although toxin blocks cholinergic nerve endings in the autonomic nervous system, it has also been shown that it does not block non-adrenergic non-cholinergic responses mediated by nitric oxide. This has promoted further interest in using botulinum toxin A as a treatment for overactive smooth muscles and sphincters. The introduction of this therapy has made the treatment of several clinical conditions easier, in the outpatient setting, at a lower cost and without permanent complications. This review presents current data on the use of botulinum toxin A in the treatment of pathological conditions of the gastrointestinal tract.

Effect of propofol on anal sphincter pressure during anorectal manometry

We evaluated the effect of propofol on resting anal sphincter pressure (RP) during anorectal manometry performed under general anesthesia in 20 children with chronic constipation. After propofol bolus administration, there was a significant decrease in the RP in 95% of children from a mean of 51.5 ± 15.3 to a mean nadir of 21.7 ± 10.5 mmHg (P < 0.001). The new postpropofol RP of 47.0 ± 12.4 mmHg was significantly lower compared with prepropofol RP (P < 0.0001). Propofol should be used with caution as an anesthetic agent for anorectal manometry, given the potential for confounding RP measurements.

Diffusion of aniline blue injected into the thyroarytenoid muscle as a proxy for botulinum toxin injection: an experimental study in cadaver larynges

Introduction: Endolaryngeal injection of botulinum toxin into the thyroarytenoid (TA) muscle is one of the methods for treatment of focal laryngeal dystonia. However, after treatment, there is variation in laryngeal configuration as well as the side effects reported by patients. As a consequence of the functional variability of results, it was hypothesized that botulinum toxin diffuses beyond the limits of the muscle into which it is injected.

Objectives: After injection of botulinum toxin into the TA muscle for the treatment of focal laryngeal dystonia, patients differ in terms of laryngeal configuration and side effects. We hypothesized that this toxin diffuses from the target muscle to adjacent muscles.

Method: The TA muscles of 18 cadaver larynges were injected with aniline blue (0.2 mL). After fixation in formaldehyde and nitric acid decalcification, the larynges were sectioned in the coronal plane and the intrinsic muscles were analyzed.

Results: We found diffusion of aniline blue to the lateral cricoarytenoid muscle, cricothyroid muscle, and posterior cricoarytenoid muscle in 94.3%, 42.9%, and 8.6% of the cases, respectively. In terms of the degree of diffusion to adjacent muscles, we found no differences related to the size (height and width) of the TA muscle or to gender.

Conclusions: Our findings suggest that diffusion of botulinum toxin from its injection site in the TA muscle to the lateral cricoarytenoid muscle is likely in most cases. On the other hand, diffusion to the cricothyroid muscle occurs in approximately half of cases and diffusion to the posterior cricoarytenoid muscle occurs in very few cases.

The use of botulinum toxin for the treatment of overactive bladder syndrome

Over the last 50 years, botulinum toxin has been transformed from a cause of life-threatening disease to an effective medical therapy. It has been used in a variety of specialties for different indications, significantly improving patient quality of life. A recent growing body of evidence suggests that intra-detrusor injection of botulinum toxin may have beneficial effects in patients with medication refractory detrusor overactivity and may offer a new minimally invasive alternative to patients with severe overactive bladder symptoms. To review current data regarding the effects of botulinum toxin in patients with overactive bladder, a MEDLINE^®/PubMed^® literature search was carried out. The mechanism of action, clinical usage, adverse effects, and treatment efficacy were reviewed and the results are presented in this paper.

Treatment of obstructed defecation

Obstructed defecation is a common problem that adversely affects the quality of life for many patients. Known causes of obstructed defecation include pelvic dyssynergy, rectocele, rectal intussusception, enterocele, pelvic organ prolapse, and overt rectal prolapse. Management of this condition requires an understanding of urinary, defecatory, and sexual function to achieve an optimal outcome. The goal of surgical treatment is to restore the various pelvic organs to their appropriate anatomic positions. However, there is a poor correlation between anatomic and functional results. As the pelvis contains many structures, a pelvic support or function defect frequently affects other pelvic organs. Optimal outcomes can only be achieved by selecting appropriate treatment modalities that address all of the components of a patient's problem.

Excellent response rate of anismus to botulinum toxin if rectal prolapse misdiagnosed as anismus ('pseudoanismus') is excluded

AIM

Anismus causes obstructed defecation as a result of inappropriate contraction of the puborectalis/external sphincter. Proctographic failure to empty after 30 s is used as a simple surrogate for simultaneous electromyography/proctography. Botulinum toxin is theoretically attractive but efficacy is variable. We aimed to evaluate the efficacy of botulinum toxin to treat obstructed defecation caused by anismus.

METHOD

Botulinum toxin was administered, under local anaesthetic, into the puborectalis/external sphincter of patients with proctographic anismus. Responders (resolution followed by recurrence of obstructed defecation over a 1- to 2-month period) underwent repeat injection. Nonresponders underwent rectal examination under anaesthetic (EUA). EUA-diagnosed rectal prolapse was graded using the Oxford Prolapse Grade 1-5.

RESULTS

Fifty-six patients were treated with botulinum toxin. Twenty-two (39%) responded initially and 21/22 (95%) underwent repeat treatment. At a median follow up of 19.2 (range, 7.0-30.4) months, 20/21 (95%) had a sustained response and required no further treatment. Isolated obstructed defecation symptoms (OR = 7.8, P = 0.008), but not proctographic or physiological factors, predicted response on logistic regression analysis. In 33 (97%) of 34 nonresponders, significant abnormalities were demonstrated at EUA: 31 (94%) had a grade 3-5 rectal prolapse, one had internal anal sphincter myopathy and one had a fissure. Exclusion of these alternative diagnoses revised the initial response rate to 96%.

CONCLUSION

Simple proctographic criteria overdiagnose anismus and underdiagnose rectal prolapse. This explains the published variable response to botulinum toxin. Failure to respond should prompt EUA seeking undiagnosed rectal prolapse. A response to an initial dose of botulinum toxin might be considered a more reliable diagnosis of anismus than proctography.

Functional disorders of defecation: evaluation and treatment

Functional disorders of defecation are common and often overlap with slow-transit constipation. They are comprised of functional obstructive conditions such as dyssynergic defecation, as well as structural obstructive conditions such as rectal prolapse, excessive perineal descent, and rectocele. Evaluation includes detailed history and rectal and pelvic exam together with physiologic tests such as anorectal manometry, balloon expulsion test, defecography, and MRI. Treatment involves several medical, behavioral, and surgical approaches. Recently, randomized controlled trials have shown that biofeedback therapy is an effective treatment for dyssynergic defecation. Stapled transanal rectal resection appears to be a promising technique for treating defecation disorders associated with rectocele, excessive perineal descent, and mucosal intussusception, but controlled trials are lacking.

Endoscopy in the diagnosis and management of motility disorders

BACKGROUND

Gastrointestinal illness may result from either an underlying structural abnormality (e.g. neoplastic obstruction), or a functional disorder (e.g. motor diarrhea), or both (e.g. achalasia with squamous esophageal cancer).

AIMS

The purpose of this study was to highlight the potential value and role of endoscopy in the recognition and management of patients with functional and motility disorders.

METHODS

We performed a literature review in PubMed.

RESULTS

Diagnostic and therapeutic endoscopy may be under-used by motility-oriented gastroenterologists; in contrast, motility and other functional studies may be under-used by endoscopists. Yet, many areas of cross-exchange exist.

CONCLUSIONS

This review aims to guide the appropriate indications for the use of endoscopy in diagnosing and treating functional GI and motility disorders and serve as a bridge and a forum of exchange between endoscopists and motility specialists.

Comparative study between surgical and non-surgical treatment of anismus in patients with symptoms of obstructed defecation: a prospective randomized study

PURPOSE

This study came to compare the results of biofeedback retraining biofeedback (BFB), botulinum toxin botulinum type A (BTX-A) injection and partial division of puborectalis (PDPR) in the treatment of anismus patients.

PATIENTS AND METHODS

Consecutive patients treated for anismus fulfilled Rome II criteria for functional constipation at our institution were evaluated for inclusion. Participants were randomly allocated to receive BFB, BTX-A injection, and PDPR. All patients underwent anorectal manometry, balloon expulsion test, defecography, and electromyography activity of the anal sphincter. Follow up was conducted weekly in the first month then monthly for about 1 year. Study variables included clinical improvement, patient satisfaction, and objective improvement.

RESULTS

Sixty patients with anismus were randomized and completed the study. The groups differed significantly regarding clinical improvement at 1 month (50% for BFB, 75%BTX-A injection, and 95% for PDPR, P = 0.006) and differences persisted at 1 year (30% for BFB, 35%BTX-A injection, and 70% for PDPR, P = 0.02). Constipation score of the patients significantly improved postPDPR and BTX-A injection. Manometric relaxation was achieved significantly in the three groups.

CONCLUSION

Biofeedback retraining has a limited therapeutic effect, BTX-A injection seems to be successful for temporary treatment but PDPR is found to be an effective with lower morbidity in contrast to its higher success rate in treating anismus.

Transcutaneous needle-free injection of botulinum toxin: a novel treatment of childhood constipation and anal fissure

PURPOSE

Constipation is a common problem in children, and when it becomes chronic fecal impaction, overflow soiling and megarectum may develop. Children with chronic idiopathic constipation (IC) may not respond to conventional treatments of laxatives, enemas, and toilet training. The aims of the study were to evaluate the long-term outcome of transcutaneous needle-free injection of botulinum toxin (TNFBT) into the external anal sphincter (EAS) and to assess the extent of the toxin penetration into the sphincter.

METHOD

Children were recruited if symptomatic with chronic constipation, soiling, painful defecation, and withholding behavior requiring disimpaction of stool and rectal biopsy under general anesthesia. A total dose of 200 U of botulinum toxin (BT) (Dysport; Ipsen Limited, Slough, United Kingdom) was injected transcutaneously into the EAS at 3 and 9-o'clock positions using J-tip needle-free syringes (National Medical Products Inc, Irvine, Calif). The depth and width of toxin penetration was assessed by endosonography. Outcome was measured by a validated symptom severity (SS) score questionnaire. The total SS score ranged between 0 (best) and 65 (worst). The outcome was compared with 31 children in a comparable historical control group at 3 and 12-month follow-up.

RESULTS

Sixteen children were recruited with median age of 6.11 (range, 3-14.85) years and median duration of symptoms of 3.9 years (1.6-11.5). On endosonography, the median depth and width of BT penetration was 8 (7-10) mm and 8 (6-10) mm, respectively. At 3-month follow-up, the median SS score improved in all children after TNFBT from 32.50 (5-57) to 7.50 (0-26) (Wilcoxon's P < .0001). There were significant improvements in symptoms of constipation, soiling, painful defecation, general health and behavior, and fecal impaction of rectum (P < .05). Anal fissures healed in all 4 children. The SS score in the control group improved from 33 (12-49) to 15 (0-40) (P < .0001). At 12-month follow-up, the improvement of SS score in TNFBT group was significantly more than the control group as follows: 4 (0-25) vs 15 (0-51), respectively (Mann-Whitney U P < .002). Three patients had a second TNFBT injection for relapsed symptoms. There were no complications. The transcutaneous needle-free injection of botulinum toxin eliminates the risk of intravascular injection or needlestick injury. The transcutaneous needle-free injection of botulinum toxin also has other therapeutic applications including an alternative therapy to biofeedback training for dyssynergia of the EAS, treatment of muscle limb spasticity in cerebral palsy, and cosmetic treatment of overactive facial muscles and wrinkles and hyperhydrosis.

CONCLUSION

Transcutaneous needle-free injection of botulinum toxin into the external anal sphincter is a novel and safe new treatment of chronic idiopathic constipation and anal fissure in children. A second injection may be required in 20% of patients.

Vaginismus: results of treatment with botulin toxin

In view of the long-term therapy necessary to cure vaginismus and specially persistent cases, we considered using botulin toxin (BT) injections for the treatment of such cases. Eight women (mean age 26.6 +/- 1.2 years) with vaginismus were treated with BT. Another five women with vaginismus, matching the eight patients in age, acted as controls. The patients in the study group were injected with BT (25 IU diluted in 1 ml saline) into each of the two bulbospongiosus muscles. Control patients were injected with saline. Mean follow-up was 10.2 +/- 3.3 months. All the patients injected with BT improved. The couples could achieve satisfactory intromission. No patient was in need of re-injection and there was no recurrence during the follow-up period. Control subjects did not improve with the saline injection into the bulbospongiosus muscle. In conclusion, BT injection effected cure in all of the vaginismus patients with no complications or recurrence. The technique is simple, easy, cost-effective, not time-consuming and can be achieved on an outpatient basis.

Clinical trial: effects of botulinum toxin on Levator ani syndrome--a double-blind, placebo-controlled study

BACKGROUND

Levator ani syndrome is characterized by anorectal discomfort/pain, treatment of which is unsatisfactory. We hypothesized that Botulinum toxin relieves spasm and improves symptoms.

AIM

To perform a randomized, placebo-controlled, crossover study to examine the efficacy and safety of botulinum toxin in patients with levator ani syndrome.

METHODS

Twelve patients with levator ani syndrome (>or=1 year) received anal intra sphincteric injections of 100 units of botulinum toxin A and placebo at 90-day intervals using EMG guidance. Daily frequency, severity, duration and intensity of pain (VAS) were recorded. Anorectal manometry, balloon expulsion and pudendal nerve latency tests were performed to examine the physiological changes and adverse effects.

RESULTS

Seven patients (male/female = 4/3) completed the study and three had incomplete data, but all 10 underwent in an ITT analysis; two others dropped out. After administration of botulinum toxin, the mean frequency, intensity and duration of pain were unchanged (P = 0.31) compared with baseline. The 90-day mean VAS pain score was 6.79 +/- 0.27 vs. baseline score of 7.08 +/- 0.29 (P = 0.25). Anal sphincter pressures, rectal sensory thresholds, pudendal nerve latency and balloon expulsion times were unchanged after drug or placebo administration.

CONCLUSIONS

Injection of botulinum toxin into anal sphincter is safe, but it does not improve anorectal pain in levator ani syndrome.

Comparative study between botulinum toxin injection and partial division of puborectalis for treating anismus

OBJECTIVES

The objective of this study was to compare the results of partial division of puborectalis (PDPR) versus local botulinum toxin type A (BTX-A) injection in treating patients with anismus.

PATIENTS AND METHODS

This prospective randomized study included 30 male patients suffering from anismus. Diagnosis was made by clinical examination, barium enema, colonoscopy, colonic transit time, anorectal manometry, balloon expulsion test, defecography, and electromyography. Patients were randomized into: group I which included 15 patients who were injected with BTX-A and group II which included 15 patients who underwent bilateral PDPR. Follow-up was conducted for about 1 year. Improvement was considered when patients returned to their normal habits.

RESULTS

BTX-A injection achieved initial success in 13 patients (86.7%). However, long-term success persisted only in six patients (40%). This was in contrast to PDPR which achieved initial success in all patients (100%) with a long-term success in ten patients (66.6%). Recurrence was observed in seven patients (53.8%) and five patients (33.4%) following BTX-A injection and PDPR, respectively. Minor degrees of incontinence were confronted in two patients (13.3%) following PDPR.

CONCLUSION

BTX-A injection seems to be successful for temporary treatment of anismus.

Comparative study between biofeedback retraining and botulinum neurotoxin in the treatment of anismus patients

PURPOSE

Anismus is a significant cause of chronic constipation. This study came to revive the results of BFB training and BTX-A injection in the treatment of anismus patients.

MATERIALS AND METHODS

Forty-eight patients with anismus (33 women; mean age 39.6 +/- 15.9) were included in this study. All patients fulfilled Rome II criteria for functional constipation. All patients underwent anorectal manometry, balloon expulsion test, defecography, and electromyography (EMG) activity of the EAS. All patients had non-relaxing puborectalis muscle. The patients were randomized into two groups. Group I patients received biofeedback therapy, two times per week for about 1 month. Group II patients were injected with BTX-A. Follow-up was conducted weekly in the first month then monthly for about 1 year.

RESULTS

In the BFB training group, three patients quit before the end of sessions with no improvement; initial improvement was recorded in 12 patients (50%) while long-term success was recorded in six patients (25%). In the BTX-A group, clinical improvement was recorded in 17 patients (70.83%), but the improvement persisted only in eight patients (33.3%). There is a significant difference between BTX-A group and BFB group regarding the initial success, but this significant difference disappeared at the end of follow-up. Manometric relaxation was achieved significantly post-BFB and post-BTX-A injection with no significant difference between the two groups.

CONCLUSIONS

Biofeedback training has a limited therapeutic effect on patients suffering from anismus. BTX-A injection seems to be successful for temporary treatment of anismus.

Constipation: evaluation and treatment of colonic and anorectal motility disorders

This article focuses on the colonic and anorectal motility disturbances that are associated with chronic constipation and their management. Functional chronic constipation consists of three overlapping subtypes: slow transit constipation, dyssynergic defecation, and irritable bowel syndrome with constipation. The Rome criteria may serve as a useful guide for making a clinical diagnosis of functional constipation. Today, an evidence-based approach can be used to treat patients with chronic constipation. The availability of specific drugs for the treatment of chronic constipation, such as tegaserod and lubiprostone, has enhanced the therapeutic armamentarium for managing these patients. Randomized controlled trials have also established the efficacy of biofeedback therapy in the treatment of dyssynergic defecation.

Systematic review of randomized controlled trials of the effectiveness of biofeedback for pelvic floor dysfunction

BACKGROUND

Pelvic floor dysfunction (PFD) is a type of functional constipation. The effectiveness of biofeedback as a treatment remains unclear.

METHODS

A systematic review of all randomized controlled trials evaluating the effectiveness of biofeedback in adults with PFD was carried out. All online databases from 1950 to 2007 were searched. This was supplemented by hand searching references of retrieved articles.

RESULTS

Seven trials fulfilled the inclusion criteria. Three compared biofeedback with non-biofeedback treatments and four compared different biofeedback modalities. Electromyography feedback was most widely utilized. The trials were heterogeneous with varied inclusion criteria, treatment protocols and definitions of success. Most had methodological limitations. Quality of life and psychological morbidity were assessed rarely. Meta-analysis of the studies involving any form of biofeedback compared with any other treatment suggested that biofeedback conferred a sixfold increase in the odds of treatment success (odds ratio 5.861 (95 per cent confidence interval 2.175 to 15.794); random-effects model).

CONCLUSION

Although biofeedback is the recommended treatment for PFD, high-quality evidence of effectiveness is lacking. Meta-analysis of the available evidence suggests that biofeedback is the best option, but well designed trials that take into account quality of life and psychological morbidity are needed.

Dyssynergic defecation and biofeedback therapy

Constipation caused by dyssynergic defecation is common and affects up to one half of patients with this disorder. It is possible to diagnose this problem through history, prospective stool diaries, and anorectal physiologic tests. Randomized controlled trials have now established that biofeedback therapy is not only efficacious but superior to other modalities and that the symptom improvement is caused by a change in underlying pathophysiology. Development of user friendly approaches to biofeedback therapy and use of home biofeedback programs will significantly enhance the adoption of this treatment by gastroenterologists and colorectal surgeons.

Constipation: evaluation and treatment of colonic and anorectal motility disorders

This article focuses on the colonic and anorectal motility disturbances that are associated with chronic constipation and their management. Functional chronic constipation consists of three overlapping subtypes: slow transit constipation, dyssynergic defecation, and irritable bowel syndrome with constipation. The Rome criteria may serve as a useful guide for making a clinical diagnosis of functional constipation. Today, an evidence-based approach can be used to treat patients with chronic constipation. The availability of specific drugs for the treatment of chronic constipation, such as tegaserod and lubiprostone, has enhanced the therapeutic armamentarium for managing these patients. Randomized controlled trials have also established the efficacy of biofeedback therapy in the treatment of dyssynergic defecation.

Current concepts in anal fissures

INTRODUCTION

Anal fissure is a common and distressing problem the true incidence of which is probably higher than recorded. There is a progressive understanding of the etiopathogenesis of this entity and the changing trend in its management approach. This is a systematic review of available published literature looking at current management options in anal fissures.

METHODS

A MEDLINE-based search of the relevant literature from 1970 to 2004 was performed on the current concepts in etiopathogenesis and management of anal fissure.

RESULTS

The current opinion is a drift toward conservative measures as the first- and second-line approaches rather than surgery for treatment of anal fissure. Simple and readily available measures with less complication, good patient compliance, and satisfaction requiring no hospitalization should first be considered.

CONCLUSIONS

Most anal fissures heal with medical therapy, but their limitations include side effects, poor compliance, and recurrence of the fissure. A cautious surgical approach is required to treat those who do not respond to medical therapy.

Botulinum toxin, a new treatment modality for chronic idiopathic constipation in children: long-term follow-up of a double-blind randomized trial

BACKGROUND

Myectomy of the internal anal sphincter (IAS) has been performed on some children after failure of medical treatment to treat idiopathic constipation. The aim of this study was to compare botulinum toxin injection with myectomy of the IAS in the treatment of chronic idiopathic constipation and soiling in children.

METHODS

This was a double-blind randomized trial. Patients between 4 and 16 years old were included in the study if they had failed to respond to laxative treatment and anal dilatation for chronic idiopathic constipation. All study patients had anorectal manometry and anal endosonography under ketamine anesthesia. Outcome was measured using a validated symptom severity (SS) scoring system, with scores ranging from 0 to 65.

RESULTS

Of 42 children, 21 were randomized to the botulinum group and 21 were randomized to the myectomy group. At the 3-month follow-up, the median preoperative SS score improved from 34 (range = 19-47) to 20 (range = 2-43) in the botulinum group (P < .001) and from 31 (range = 18-49) to 19 (range = 3-47) in the myectomy group (P < .002). At the 12-month follow-up, the scores were 19 (range = 0-45) and 14.5 (range = 0-41) for the botulinum group and the myectomy group, respectively (P < .0001). There was no complication in both groups.

CONCLUSION

Botulinum toxin is equally effective as and less invasive than myectomy of the IAS for chronic idiopathic constipation and fecal incontinence in children.

Botulinum toxin for gastrointestinal disorders: therapy and mechanisms

Botulinum toxin has gained widespread acceptance as a treatment option for various spastic gastrointestinal disorders such as achalasia, gastroparesis, sphincter of Oddi dysfunction, chronic anal fissures, and pelvic floor dyssnergia, despite the lack of strong evidence supporting its use in many of these diseases. This review summarizes the trials investigating the use of BoNT since it was first utilized as a treatment in achalasia. BoNT has proven to be safe, but long-term efficacy in many disorders has not been observed, primarily due to is relatively short duration of action. BoNT may be most useful in confirming a diagnosis which can lead to a more definitive treatment modality. Furthermore, its safety profile allows it to be a useful alternative in patients who are at high risk for invasive procedures.

Management of bladder, prostatic and pelvic floor disorders

Since its introduction in the late 1970s for the treatment of strabismus and blepharospasm, botulinum toxin (BoNT) has been increasingly used in the interventional treatment of several other disorders characterized by excessive or inappropriate muscle contractions. Over the years, the number of primary clinical publications has grown exponentially, and still continues to increase. It has been shown that BoNT blocks cholinergic nerve endings in the autonomic nervous system but does not block non-adrenergic non-cholinergic responses mediated by nitric oxide (NO). The present paper reviews a number of recent clinical indications for urological and pelvic floor dysfunctions, such as overactive and neurogenic bladder, non-bacterial prostatitis, benign prostatic hyperplasia, chronic anal fissure, or conditions associated to hyperactivity of the puborectalis muscle during straining. These indications provide a new promising palette of indications for future usage of BoNT in clinical practice.

Outlet type constipation in Parkinson's disease: results of botulinum toxin treatment

BACKGROUND

Constipation is one of the most common autonomic dysfunctions observed in Parkinson's disease.

AIM

To investigate the efficacy of injections of botulinum toxin in improving rectal emptying in these patients.

METHODS

Eighteen Parkinson's disease patients with outlet constipation were included in the study. The patients were treated with type A botulinum toxin, injected into two sites on either side of the puborectalis muscle under ultrasonographic guidance.

RESULTS

Symptomatic improvement was noted in 10 patients, at 2 months evaluation. In these subjects, anorectal manometry demonstrated decreased tone during straining from 96.2 +/- 17.1 to 45.9 +/- 16.2 mmHg at 1 month evaluation (P = 0.00001) and to 56.1 +/- 10.7 mmHg at 2 months (P = 0.00001). Pressure during straining was lower than resting anal pressure at the same times in all patients. Defecography after the treatment showed improvement in anorectal angle during straining, which increased from 99.1 +/- 8.4 degrees to 121.7 +/- 12.7 degrees (P = 0.00001) at 2 months.

CONCLUSIONS

Botulinum toxin injections may be a useful treatment for Parkinson's disease patients affected by outlet-obstruction constipation. The treatment is safe and simple. However, because the effects of the toxin wear off within 3 months of administration, repeated injections could be necessary to maintain the clinical improvement.

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.

Treatment of obstructed defecation

Obstructed defecation is a common problem that adversely affects the quality of life for many patients. Known causes of obstructed defecation include pelvic dyssynergy, rectocele, rectal intussusception, enterocele, pelvic organ prolapse, and overt rectal prolapse. Management of this condition requires an understanding of urinary, defecatory, and sexual function to achieve optimal outcomes. The goal of surgical treatment is to restore the various pelvic organs to their appropriate anatomic positions. However, there is a poor correlation between anatomic and functional results. It must be remembered that the pelvis contains many structures and that defects of pelvic support or function frequently affect other pelvic organs. Optimal outcomes can be achieved only by selecting appropriate treatment modalities that address all of the components of an individual patient's problem.

From frown lines to fissures: Therapeutic uses for botulinum toxin

INTRODUCTION

Since the pharmacological mode of action of botulinum toxin (BTX) has been elucidated, its therapeutic potential has been increasingly recognised. The aims of this review were to summarize our current understanding of the pharmacological action of this agent and to review its therapeutic uses.

METHODS

An electronic literature search with Medline (January 1965 to December 2004) was carried out to identify articles related to the pharmacological mode of action and clinical uses for botulinum toxin using the keyword "botulinum toxin".

RESULTS AND CONCLUSION

Botulinum toxin A is emerging as a valuable clinical tool, both for diagnostic and therapeutic purposes in a wide variety of disorders, and is already the treatment of choice for selected conditions. Better understanding of its modes of action may identify alternative targets for pharmacological intervention, and may allow development of longer acting drugs with lower immunogenicity. Therapeutic uses of BTX-A must be assessed systematically in prospective studies, and the clinical role of other subtypes requires evaluation.

[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.