Botulinum toxin type-A in therapy of patients with anismus

Botulinum toxin type A injection combined with biofeedback in the treatment of spastic pelvic floor syndrome

BACKGROUND

Spastic pelvic floor syndrome (SPFS) is a refractory pelvic floor disease characterized by abnormal (uncoordinated) contractions of the external anal sphincter and puborectalis muscle during defecation, resulting in rectal emptation and obstructive constipation. The clinical manifestations of SPFS are mainly characterized by difficult defecation, often accompanied by a sense of anal blockage and drooping. Manual defecation is usually needed during defecation. From physical examination, it is commonly observed that the patient's anal muscle tension is high, and it is difficult or even impossible to enter with his fingers.

AIM

To investigate the characteristics of anorectal pressure and botulinum toxin A injection combined with biofeedback in treating pelvic floor muscle spasm syndrome.

METHODS

Retrospective analysis of 50 patients diagnosed with pelvic floor spasm syndrome. All patients underwent pelvic floor surface electromyography assessment, anorectal dynamics examination, botulinum toxin type A injection 100 U intramuscular injection, and two cycles of biofeedback therapy.

RESULTS

After the botulinum toxin A injection combined with two cycles of biofeedback therapy, the patient's postoperative resting and systolic blood pressure were significantly lower than before surgery (P < 0.05). Moreover, the electromyography index of the patients in the resting stage and post-resting stages was significantly lower than before surgery (P < 0.05).

CONCLUSION

Botulinum toxin A injection combined with biofeedback can significantly reduce pelvic floor muscle tension in treating pelvic floor muscle spasm syndrome. Anorectal manometry is an effective method to evaluate the efficacy of treatment objectively. However, randomized controlled trials are needed.

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.

State of the Art Bowel Management for Pediatric Colorectal Problems: Functional Constipation

BACKGROUND

Functional constipation (FC) affects up to 32% of the pediatric population, and some of these patients are referred to pediatric surgery units to manage their constipation and/or fecal incontinence. The aim of the current paper is to report the recent updates on the evaluation and management of children with FC as a part of a manuscript series on bowel management in patients with anorectal malformations, Hirschsprung disease, spinal anomalies, and FC.

METHODS

A literature search was performed using Medline/PubMed, Google Scholar, Cochrane, and EMBASE databases and focusing on the manuscripts published within the last 5-10 years.

RESULTS

The first step of management of children with FC is to exclude Hirschsprung disease with a contrast study, examination under anesthesia, anorectal manometry (AMAN). If AMAN shows absent rectoanal inhibitory reflex, a rectal biopsy is performed. Internal sphincter achalasia or high resting pressures indicate botulinum toxin injection. Medical management options include laxatives, rectal enemas, transanal irrigations, and antegrade flushes. Those who fail conservative treatment require further assessment of colonic motility and can be candidates for colonic resection. The type of resection (subtotal colonic resection vs. Deloyer's procedure) can be guided with a balloon expulsion test.

CONCLUSION

Most of the patients with FC referred for surgical evaluation can be managed conservatively. Further studies are required to determine an optimal strategy of surgical resection in children unresponsive to medical treatment.

Do Bacteria Provide an Alternative to Cancer Treatment and What Role Does Lactic Acid Bacteria Play?

Cancer is one of the leading causes of mortality and morbidity worldwide. According to 2022 statistics from the World Health Organization (WHO), close to 10 million deaths have been reported in 2020 and it is estimated that the number of cancer cases world-wide could increase to 21.6 million by 2030. Breast, lung, thyroid, pancreatic, liver, prostate, bladder, kidney, pelvis, colon, and rectum cancers are the most prevalent. Each year, approximately 400,000 children develop cancer. Treatment between countries vary, but usually includes either surgery, radiotherapy, or chemotherapy. Modern treatments such as hormone-, immuno- and antibody-based therapies are becoming increasingly popular. Several recent reports have been published on toxins, antibiotics, bacteriocins, non-ribosomal peptides, polyketides, phenylpropanoids, phenylflavonoids, purine nucleosides, short chain fatty acids (SCFAs) and enzymes with anticancer properties. Most of these molecules target cancer cells in a selective manner, either directly or indirectly through specific pathways. This review discusses the role of bacteria, including lactic acid bacteria, and their metabolites in the treatment of cancer.

Antegrade continence enemas in children with functional constipation and dyssynergic defecation: Go or no go?

OBJECTIVE

To assess outcomes of children with functional constipation after antegrade continence enemas (ACEs) and determine if pre operative anorectal manometry (AMAN) findings, including dyssynergic defecation, are associated with outcomes.

METHODS

A retrospective review of pediatric patients with functional constipation who received a Malone appendicostomy or cecostomy after failed medical management was conducted. Patients were included if they had AMAN data prior to their operation. Patients that underwent colonic resection were excluded. Demographics, clinical characteristics, manometry results, and post ACE outcomes were obtained. Descriptive statistics were performed.

RESULTS

Thirty-nine patients were identified with median age at ACE of 8.9 years (IQR: 7.2-12.6) and median follow-up of 2.5 years (IQR: 1.8-3.2 years). Twenty patients (51%) were female and most (35, 92%) were White. All patients had severe constipation prior to ACE and 59% had fecal incontinence. Thirty-four patients (87%) received a Malone and 5 (13%) received a cecostomy. Post ACE, 35 (90%) were clean with daily flushes and 6 (15%) eventually successfully transitioned to laxatives only. Awake AMAN and balloon expulsion test were performed in 15 patients, with 14 (93%) displaying evidence of dyssynergic defecation. Twelve of 14 of patients (86%) with dyssynergia were clean with ACE at follow-up. because of the majority of patients being clean post ACE, there was limited power to detect predictors of poor outcomes.

CONCLUSIONS

ACEs are successful treatment options for patients with severe constipation and fecal incontinence, including those with dyssynergic defecation. Larger studies are needed to identify factors predictive of poor outcomes.

LEVEL OF EVIDENCE

III.

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.

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.

Pelvic Floor Nonrelaxation: Approach to Evaluation and Treatment

Dyssynergic defecation can be a complex, burdensome condition. A multidisciplinary approach to these patients is often indicated based on concomitant pathology or symptomatology across the pelvic organs. Escalating treatment options should be based on shared decision making and include medical and lifestyle optimization, pelvic floor physical therapy with biofeedback, Botox injection, sacral neuromodulation, rectal irrigation, and surgical diversion.

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.

Current perspectives on the diagnosis and management of functional anorectal disorders in patients with inflammatory bowel disease

Despite advances in inflammatory bowel disease (IBD) therapies, a significant proportion of patients with quiescent disease experience persistent, debilitating symptoms of faecal incontinence (FI), urgency and defaecatory disorders due to anorectal dysfunction. Such symptoms are often underreported or misdiagnosed and can lead to potentially premature treatment 'escalation' and under-utilisation of pelvic floor investigations. In this review article, we consider putative pathophysiological post-inflammatory changes resulting in altered anorectal sensitivity, motility and neuromuscular coordination and how this may drive symptoms in quiescent IBD. Finally, we discuss a pragmatic approach to investigating and managing anorectal dysfunction and highlight areas for future research for this often-neglected group of patients.

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.

The Mexican consensus on chronic constipation

INTRODUCTION

Significant advances have been made in the knowledge and understanding of the epidemiology, pathophysiology, diagnosis, and treatment of chronic constipation, since the publication of the 2011 guidelines on chronic constipation diagnosis and treatment in Mexico from the Asociación Mexicana de Gastroenterología.

AIMS

To present a consensus review of the current state of knowledge about chronic constipation, providing updated information and integrating the new scientific evidence.

METHODS

Three general coordinators reviewed the literature published within the time frame of January 2011 and January 2017. From that information, 62 initial statements were formulated and then sent to 12 national experts for their revision. The statements were voted upon, using the Delphi system in 3 voting rounds (2 electronic and one face-to-face). The statements were classified through the GRADE system and those that reached agreement >75% were included in the consensus.

RESULTS AND CONCLUSIONS

The present consensus is made up of 42 final statements that provide updated knowledge, supplementing the information that had not been included in the previous guidelines. The strength of recommendation and quality (level) of evidence were established for each statement. The current definitions of chronic constipation, functional constipation, and opioid-induced constipation are given, and diagnostic strategies based on the available diagnostic methods are described. The consensus treatment recommendations were established from evidence on the roles of diet and exercise, fiber, laxatives, new drugs (such as prucalopride, lubiprostone, linaclotide, plecanatide), biofeedback therapy, and surgery.

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.

Chronic constipation

Chronic constipation is a prevalent condition that severely impacts the quality of life of those affected. Several types of primary chronic constipation, which show substantial overlap, have been described, including normal-transit constipation, rectal evacuation disorders and slow-transit constipation. Diagnosis of primary chronic constipation involves a multistep process initiated by the exclusion of 'alarm' features (for example, unintentional weight loss or rectal bleeding) that might indicate organic diseases (such as polyps or tumours) and a therapeutic trial with first-line treatments such as dietary changes, lifestyle modifications and over-the-counter laxatives. If symptoms do not improve, investigations to diagnose rectal evacuation disorders and slow-transit constipation are performed, such as digital rectal examination, anorectal structure and function testing (including the balloon expulsion test, anorectal manometry or defecography) or colonic transit tests (such as the radiopaque marker test, wireless motility capsule test, scintigraphy or colonic manometry). The mainstays of treatment are diet and lifestyle interventions, pharmacological therapy and, rarely, surgery. This Primer provides an introduction to the epidemiology, pathophysiological mechanisms, diagnosis, management and quality of life associated with the commonly encountered clinical problem of chronic constipation in adults unrelated to opioid abuse.

Review article: dyssynergic defaecation and biofeedback therapy in the pathophysiology and management of functional constipation

BACKGROUND

Functional constipation is a common clinical presentation in primary care. Functional defaecation disorders are defined as the paradoxical contraction or inadequate relaxation of the pelvic floor muscles during attempted defaecation (dyssynergic defaecation) and/or inadequate propulsive forces during attempted defaecation. Prompt diagnosis and management of dyssynergic defaecation is hindered by uncertainty regarding nomenclature, diagnostic criteria, pathophysiology and efficacy of management options such as biofeedback therapy.

AIM

To review the evidence pertaining to the pathophysiology of functional defaecation disorders and the efficacy of biofeedback therapy in the management of patients with dyssynergic defaecation and functional constipation.

METHODS

Relevant articles addressing functional defaecation disorders and the efficacy of biofeedback therapy in the management of dyssynergic defaecation and functional constipation were identified from a search of Pubmed, MEDLINE Ovid and the Cochrane Library.

RESULTS

The prevalence of dyssynergic defaecation in patients investigated for chronic constipation is as many as 40%. Randomised controlled trials have demonstrated major symptom improvement in 70%-80% of patients undergoing biofeedback therapy for chronic constipation resistant to standard medical therapy and have determined it to be superior to polyethylene glycol laxatives, diazepam or sham therapy. Long-term studies have shown 55%-82% of patients maintain symptom improvement.

CONCLUSIONS

Dyssynergic defaecation is a common clinical condition in patients with chronic constipation not responding to conservative management. Biofeedback therapy appears to be a safe, successful treatment with sustained results for patients with dyssynergic defaecation. Further studies are required to standardise the diagnosis of dyssynergic defaecation in addition to employing systematic protocols for biofeedback therapy.

Botulinum Toxin A for Controlling Obesity

Rapid growth of the overweight population and the number of obese individuals in recent decades suggests that current strategies based on diet, exercise, and pharmacological knowledge are not sufficient to address this epidemic. Obesity is the result of a high caloric intake and energy storage, not counterbalanced by an equally important energy expense. Botulinum toxin type A (BoNT-A) use is rapidly expanding to include treatment of a variety of ophthalmological, gastrointestinal, urological, orthopedic, dermatological, secretory, painful, and cosmetic disorders. Many studies evaluating the effect of BoNT-A in gastric antrum e/o fundus for the treatment of obesity have been published. This treatment modality was based on the observation that gastric injection of BoNT-A in laparatomized rats induced a significant reduction of food intake and body weight. These studies have been published yielding debated results. Differences in the selection of patients, the doses of BoNT-A, the method of administration of the toxin, and the instruments of evaluation of some parameters among these studies may be the cause. In this review, it will study the state-of-the-art use of BoNT-A in obesity basic science models and review the clinical evidence on the therapeutic applications of BoNT-A for obesity.

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.

Complications Following Anorectal Surgery

Anorectal surgery is well tolerated. Rates of minor complications are relatively high, but major postoperative complications are uncommon. Prompt identification of postoperative complications is necessary to avoid significant patient morbidity. The most common acute complications include bleeding, infection, and urinary retention. Pelvic sepsis, while may result in dramatic morbidity and even mortality, is relatively rare. The most feared long-term complications include fecal incontinence, anal stenosis, and chronic pelvic pain.

Endoscopic botox injections in therapy of refractory gastroparesis

Gastroparesis (GP) is a common disease seen in gastroenterology practice particularly in western countries, and it may be underdiagnosed. The available drug therapies for this condition are quite disappointing. Botulinum toxin type A (BT) has been found to be effective therapy in various spastic disorders of smooth muscle of gastrointestinal tract. However, the benefits of BT injections in GP have been unclear. Several retrospective and open label studies have shown clinical advantages of intrapyloric Botulinum toxin type A injections, while two small randomized trials did not show positive results. Therefore, the available published studies yielded conflicting results leading to fading out of botox therapy for GP. We recognize possible clinical benefit of BT injections without any disadvantages of this treatment. We are calling for revisiting the endoscopy guided botox therapy in refractory GP. In this review we discuss important features of these studies pointing out differences in results among them. Differences in patient selection, doses and method of administration of botox toxin in the prior studies may be the cause of conflicting results. The mechanism of action, indications, efficacy and side-effects of BT are reviewed. Finally, we recognize limited evidence to recommend BT in GP and calling attention for future research in this field since no advances in drug management had been made in the last two decades.

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.

Gastrointestinal Symptoms in Parkinson Disease: Clinical Aspects and Management

Although it is now generally recognized that the clinical spectrum of Parkinson disease (PD) is broader than its defining motor aspects, its various non-motor symptoms are often not routinely assessed in the clinical setting. As most of these symptoms are amenable to treatment, improved recognition would lead to more comprehensive management of the disease, and ultimately improve the quality of life for PD patients. In an attempt to increase the general awareness of physicians caring for these patients, this article focuses on the clinical manifestations and treatment of the gastrointestinal symptoms most commonly experienced by PD patients, as well as on the gastrointestinal side effects of antiparkinsonian treatments.

Management of pelvic floor disorders: biofeedback and more

OPINION STATEMENT

Defecatory disorders (DD) and fecal incontinence (FI) are common conditions. DD are primarily attributable to impaired rectoanal function during defecation or structural defects. FI is caused by one or more disturbances of anorectal continence mechanisms. Altered stool consistency may be the primary cause or may unmask anorectal deficits in both conditions. Diagnosis and management requires a systematic approach beginning with a thorough clinical assessment. Symptoms do not reliably differentiate a DD from other causes of constipation such as slow or normal transit constipation. Therefore, all constipated patients who do not adequately respond to medical therapy should be considered for anorectal testing to identify a DD. Preferably, two tests indicating impaired defecation are required to diagnose a DD. Patients with DD, or those for whom testing is not available and the clinical suspicion is high, should be referred for biofeedback-based pelvic floor physical therapy. Patients with FI should be managed with lifestyle modifications, pharmacotherapy for bowel disturbances, and management of local anorectal problems (e.g., hemorrhoids). When these measures are not beneficial, anorectal testing and pelvic floor retraining with biofeedback therapy should be considered. Sacral nerve stimulation or perianal bulking could be considered in patients who have persistent symptoms despite optimal management of bowel disturbances and pelvic floor retraining.

Botulinum toxin type-A injection to treat patients with intractable anismus unresponsive to simple biofeedback training

AIM: To evaluate the efficacy of botulinum toxin type A injection to the puborectalis and external sphincter muscle in the treatment of patients with anismus unresponsive to simple biofeedback training.

METHODS: This retrospective study included 31 patients suffering from anismus who were unresponsive to simple biofeedback training. Diagnosis was made by anorectal manometry, balloon expulsion test, surface electromyography of the pelvic floor muscle, and defecography. Patients were given botulinum toxin type A (BTX-A) injection and pelvic floor biofeedback training. Follow-up was conducted before the paper was written. Improvement was evaluated using the chronic constipation scoring system.

RESULTS: BTX-A injection combined with pelvic floor biofeedback training achieved success in 24 patients, with 23 maintaining persistent satisfaction during a mean period of 8.4 mo.

CONCLUSION: BTX-A injection combined with pelvic floor biofeedback training seems to be successful for intractable anismus.

The management of gastrointestinal symptoms in Parkinson's disease

The involvement of the autonomic nervous system in Parkinson's disease causes many non-motor symptoms, among which gastrointestinal complaints are prominent. Drooling, dyspepsia, constipation, abdominal pain and fecal incontinence are frequently a source of patient distress. Dysphagia is recognized as causing both discomfort and increased risk of serious complications. Although a diagnosis can often be established based on the reports of patients and/or caregivers, and additional testing is seldom required, these diagnoses are clearly under recognized in clinical practice. These symptoms respond to the same treatment measures used in the general population, although certain drugs with a potential to increase parkinsonian symptoms should be avoided. Increased and early identification of these symptoms can result in a significant improvement in the quality of life of Parkinson's disease patients.

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.

Botulinum toxin injections for adults with overactive bladder syndrome

BACKGROUND

Overactive bladder syndrome (OAB) is a common condition with a significant negative impact on quality of life characterised by urgency with or without urge incontinence, frequency and nocturia.  Intravesical botulinum toxin is being increasingly used to treat severe overactive bladder refractory to standard management.  An increasing body of literature is forming that supports this technique as effective, well tolerated, and safe.  This review is a substantial update of the 2007 review of the same title.

OBJECTIVES

The objective was to compare intravesical botulinum toxin with other treatments for neurogenic and idiopathic overactive bladder in adults. The hypothesis to be addressed were whether intravesical injection of botulinum toxin was better than placebo or no treatment; pharmacological and other non-pharmacological interventions; whether higher doses of botulinum toxin were better than lower doses; whether botulinum toxin in combination with other treatments was better than other treatments alone; whether one formulation of botulinum toxin is better than another; and whether one injection technique was better than another.

SEARCH METHODS

We searched the Cochrane Incontinence Group Specialised Trials Register (searched 23 February 2010). The Register contains trials identified from MEDLINE, CINAHL, the Cochrane Central Register of Controlled Trials (CENTRAL), and handsearching of journals and conference proceedings. Additionally, all reference lists of selected trials and relevant review papers were searched. No limitations were placed on the searches.

SELECTION CRITERIA

All randomised or quasi-randomised controlled trials of treatment for OAB in adults in which at least one management arm involved intravesical injection of botulinum toxin were included. Participants had either neurogenic OAB or idiopathic OAB with or without stress incontinence. Comparison interventions could include no intervention, placebo, lifestyle modification, bladder retraining, pharmacological treatments, surgery, bladder instillation techniques, neuromodulation, and different types, doses, and injection techniques of botulinum toxin.

DATA COLLECTION AND ANALYSIS

Binary outcomes were presented as relative risk and continuous outcomes by mean differences. Little data could be synthesised across studies due to differing study designs and outcome measures. Where applicable standard deviations were calculated from P values according to the formula described in section 7.7.3.3 of the Cochrane Handbook of Systematic Reviews of Interventions. Data were tabulated where possible with results taken from trial reports where this was not possible. Where multiple publications were found, the reports were treated as a single source of data.

MAIN RESULTS

Nineteen studies were identified that met the inclusion criteria.  Most patients in the studies had neurogenic OAB, but some included patients with idiopathic OAB.  All studies demonstrated superiority of botulinum toxin to placebo.  Lower doses of botulinum toxin (100 to 150 U) appeared to have beneficial effects, but larger doses (300 U) may have been more effective and longer lasting, but with more side effects.  Suburothelial injection had comparable efficacy to intradetrusor injection. The effect of botulinum toxin may last for a number of months and is dependent upon dose and type of toxin used. Patients receiving repeated doses do not seem to become refractory to botulinum toxin. Botulinum toxin appeared to have beneficial effects in OAB that quantitatively exceeded the effects of intravesical resiniferatoxin. Intravesical botulinum toxin appeared to be reasonably safe; however, one study was halted due to a perceived unacceptable rate of urinary retention. 

AUTHORS' CONCLUSIONS

Intravesical botulinum toxin appears to be an effective therapy for refractory OAB symptoms, but as yet little controlled trial data exist on benefits and safety compared with other interventions, or with placebo. Further robust data are required on long term outcomes, safety, and optimal dose of botulinum toxin for OAB.

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.

Paradoxical puborectalis contraction and increased perineal descent

Paradoxical puborectalis contraction and increased perineal descent are two forms of functional constipation presenting as challenging diagnostic and treatment dilemmas to the clinician. In the evaluation of these disorders, the clinician should take special care to exclude anatomic disorders leading to constipation. Physical examination is supplemented by additional diagnostic modalities such as cinedefecography, electromyography, manometry, and pudendal nerve tefninal motor latency. Generally, these investigations should be used in combination with the two playing the more relied upon techniques. Treatment is typically conservative with biofeedback playing a principal role with favorable results when patient compliance is emphasized. When considering paradoxical puborectalis contraction, failure of biofeedback is usually augmented with botulinum toxin injection. Increased perineal descent is generally treated with biofeedback and perineal support maneuvers. Surgery has little or no role in these conditions. The patient who insists on surgical intervention for either of these two conditions should be offered a stoma.

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.

Botulinum neurotoxin: evolution from poison, to research tool--onto medicinal therapeutic and future pharmaceutical panacea

Botulinum neurotoxin (BoNT), for more than a hundred years, has been a recognized poisonous principle in spoiled food. As its chemical structure became unraveled, and as more knowledge was gained over its mechanism of toxicity, it became clear that BoNT had the potential to act therapeutically as a targeted toxin that could inactivate specific nerve populations, and thus achieve a therapeutic goal. BoNT has evolved over the past 25 years into a viable therapeutic, now being a first line treatment for dystonia, overtly altering the course of progression of this disorder. BoNT is used for hyperhidrosis and gustatory sweating syndrome, alleviation of pain, as a treatment for overactive bladder, achalasia and anal fissure; and it has gained popularity as a cosmetic aid. Many other possible uses are being explored. The greatest potential for BoNT may lie in its being a molecular Trojan Horse - able to carry a specific enzyme or specific drug to the inside of a cancer or other type of cell while bypassing other cells and thereby having little or no ill effect. BoNT's pharmaceutical potential is boundless.

Neurologic uses of botulinum neurotoxin type A

This article reviews the current and most neurologic uses of botulinum neurotoxin type A (BoNT-A), beginning with relevant historical data, neurochemical mechanism at the neuromuscular junction. Current commercial preparations of BoNT-A are reviewed, as are immunologic issues relating to secondary failure of BoNT-A therapy. Clinical uses are summarized with an emphasis on controlled clinical trials (as appropriate), including facial movement disorders, focal neck and limb dystonias, spasticity, hypersecretory syndromes, and pain.

Botulinum toxin injections for adults with overactive bladder syndrome

BACKGROUND

Overactive bladder syndrome is a common condition with a significant negative impact on quality of life. Intravesical injection of botulinum toxin is increasingly used as an intervention for refractory overactive bladder, with a considerable body of case reports and series in the literature suggesting beneficial effects.

OBJECTIVES

The objective was to compare intravesical botulinum toxin injection with other treatments for neurogenic and idiopathic overactive bladder in adults. The hypotheses addressed were whether intravesical injection of botulinum toxin was better: than placebo or no treatment, pharmacological and other non-pharmacological interventions, whether higher doses of botulinum toxin were better than lower doses, whether botulinum toxin in combination with other treatments was better than other treatments alone, whether one formulation of botulinum toxin is better than another, and whether one injection technique was better than another.

SEARCH STRATEGY

We searched the Cochrane Incontinence Group Specialised Trials Register (searched 22 November 2005). The register contains trials identified from MEDLINE, CINAHL, the Cochrane Central Register of Controlled Trials (CENTRAL), and handsearching of journals and conference proceedings. Additionally, all reference lists of selected trials were searched. No limitations were placed on the searches.

SELECTION CRITERIA

All randomised or quasi-randomised controlled trials of treatment for overactive bladder syndrome in adults in which at least one management arm involved intravesical injection of botulinum toxin were included. Participants had either neurogenic or idiopathic overactive bladder with or without stress incontinence. Comparison interventions could include no intervention; placebo; lifestyle modification; bladder retraining; pharmacological treatments; surgery; bladder instillation techniques; neuromodulation; and different types, doses, and injection techniques of botulinum toxin.

DATA COLLECTION AND ANALYSIS

Binary outcomes were presented as relative risk and continuous outcomes by mean differences. No data could be synthesised across studies due to differing designs and outcome measures. Data were tabulated where possible with results taken from trial reports where this was not possible. Where multiple publications were found, the reports were treated as a single source of data.

MAIN RESULTS

Eight studies met the inclusion criteria. Results varied between studies. For the most part, studies reported superiority of botulinum toxin A to placebo in such outcomes as incontinence episodes, bladder capacity, maximum detrusor pressure, and quality of life. Low doses of botulinum toxin (100U to150U) appeared to have beneficial effects, but higher doses (300U) may have been more effective. Botulinum toxin appeared to have beneficial effects in overactive bladder that quantitatively exceeded the effects of intravesical resiniferatoxin.

AUTHORS' CONCLUSIONS

Intravesical botulinum toxin shows promise as a therapy for overactive bladder symptoms, but as yet too little controlled trial data exist on benefits and safety compared with other interventions, or with placebo. Practitioners should be aware that at present there is little more than anecdotal evidence, in the form of case reports to support the efficacy of intravesical botulinum toxin; there is not much in the way of substantial, robust safety data. Furthermore, the optimal dose of botulinum toxin for efficacy and safety has not yet been demonstrated.

Randomized, controlled trial shows biofeedback to be superior to alternative treatments for patients with pelvic floor dyssynergia-type constipation

PURPOSE

This study was designed to determine whether biofeedback is more effective than diazepam or placebo in a randomized, controlled trial for patients with pelvic floor dyssynergia-type constipation, and whether instrumented biofeedback is necessary for successful training.

METHODS

A total of 117 patients participated in a four-week run-in (education and medical management). The 84 who remained constipated were randomized to biofeedback (n=30), diazepam (n=30), or placebo (n=24). All patients were trained to do pelvic floor muscle exercises to correct pelvic floor dyssynergia during six biweekly one-hour sessions, but only biofeedback patients received electromyography feedback. All other patients received pills one to two hours before attempting defecation. Diary data on cathartic use, straining, incomplete bowel movements, Bristol stool scores, and compliance with homework were reviewed biweekly.

RESULTS

Before treatment, the groups did not differ on demographic (average age, 50 years; 85 percent females), physiologic or psychologic characteristics, severity of constipation, or expectation of benefit. Biofeedback was superior to diazepam by intention-to-treat analysis (70 vs. 23 percent reported adequate relief of constipation 3 months after treatment, chi-squared=13.1, P<0.001), and also superior to placebo (38 percent successful, chi-squared=5.7, P=0.017). Biofeedback patients had significantly more unassisted bowel movements at follow-up compared with placebo (P=0.005), with a trend favoring biofeedback over diazepam (P=0.067). Biofeedback patients reduced pelvic floor electromyography during straining significantly more than diazepam patients (P<0.001).

CONCLUSIONS

This investigation provides definitive support for the efficacy of biofeedback for pelvic floor dyssynergia and shows that instrumented biofeedback is essential to successful treatment.

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.

Treatment strategies in obstructed defecation and fecal incontinence

Obstructed defecation (OD) and fecal incontinence (FI) are challenging clinical problems, which are commonly encountered in the practice of colorectal surgeons and gastroenterologists. These disorders socially and psychologically distress patients and greatly impair their quality of life. The underlying anatomical and pathophysiological changes are complex, often incompletely understood and cannot always be determined. As a consequence, many medical, surgical, and behavioral approaches have been described, with no panacea. Over the past decade, advances in an understanding of these disorders together with rational and similar methods of evaluation in anorectal physiology laboratories (ARP), radiology studies, and new surgical techniques have led to promising results. In this brief review, we discuss treatment strategies and recent updates on clinical and therapeutic aspects of obstructed defecation and fecal incontinence.

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.

Defecación obstructiva. Métodos diagnósticos y tratamiento

Obstructive defecation is observed in approximately half of all patients with functional constipation. Functional constipation has been related to alterations in intestinal motility (slow transit constipation) and to pelvic floor disorders leading to obstructive defecation associated with anatomical alterations of the pelvic floor (rectocele, posterior perineal hernia, enterocele and sigmoidocele, internal rectal intussusception, occult mucosal prolapse, solitary rectal ulcer and descending perineum syndrome), or obstructive defecation without anatomical alterations (pelvic floor dyssynergy or anismus). The diagnostic methods used (history and physical examination, colonic transit time, balloon expulsion test, proctography, anorectal manometry and electromyography) are reviewed. Conservative medical treatment and the indications for surgical treatment and its results are also discussed.

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.