Ultrasound-guided intrasphincteric botulinum toxin injection relieves obstructive defecation due to Hirschsprung's disease and internal anal sphincter achalasia

Management of the child with refractory constipation

BACKGROUND

Caring for children with constipation refractory to conventional treatment can be challenging and management practices vary widely.

AIMS

To review recent advances in the evaluation and treatment of children with refractory constipation and to propose an algorithm that incorporates the latest evidence and our institutional experience.

METHODS

We performed a literature review on diagnostic tests and treatment options for children with refractory constipation.

RESULTS

Evaluation of a child with refractory constipation seeks to better understand factors contributing to an individual child's presentation. Anorectal manometry evaluating for a rectal evacuation disorder and colonic manometry evaluating for colonic dysmotility can guide subsequent treatment. For the child who has not responded to conventional treatment, a trial of newer medications like linaclotide can be helpful. Transanal irrigation offers a safe and effective alternative for families able to administer daily rectal treatment. Despite mixed evidence in children, pelvic floor biofeedback therapy can help some children with pelvic floor dyssynergia. For younger children unable to cooperate with pelvic floor therapy, or older children with refractory symptoms, internal anal sphincter botulinum toxin injection can be beneficial. Antegrade continence enema treatment can be effective for children with either normal colonic motility or segmental dysmotility. Sacral nerve stimulation is generally reserved for symptoms that persist despite antegrade continence enemas, particularly if faecal incontinence is prominent. In more severe cases, temporary or permanent colonic diversion and segmental colonic resection may be needed.

CONCLUSIONS

Recent advances offer hope for children with refractory constipation.

Applications for ultrasound in pediatric surgery

Ultrasound (US) use within pediatric surgery is expanding rapidly. While US guidance for central line placement has been common practice for many years now, advances in the quality of images, portability of US machines, and a lack of radiation associated with imaging has led to broader application in many other aspects of surgery, ranging from diagnostics to performing operations under the direction of point-of-care ultrasound (POCUS). The relatively short learning curve for providers along with excellent image quality in children due to their small size provides an easy, effective imaging modality with diverse applications. Discussed here is a broad overview of the spectrum of US use within current pediatric surgical practices.

Intrasphincteric Botox injections in Hirschsprung's disease: indications and outcome in 64 procedures over a ten-year period

BACKGROUND

Intrasphincteric botulinum toxin (Botox) injection for symptomatic postoperative anal achalasia in Hirschsprung's disease (HSCR) has found wide application in the last twenty years. The aim of this study was to describe effectiveness and functional outcome of a series of patients treated over a 10-year period.

METHODS

All consecutive HSCR patients who received intrasphincteric Botox injections between January 2007 and December 2016 were included. Demographic data and clinical features were collected. A detailed questionnaire focusing on outcome in the medium and long-term was administered to all families.

RESULTS

In the study period 64 intrasphincteric Botox injections were performed in 31 patients. Completed questionnaires were returned by 27 out of 28 eligible patients (96%) reporting improvement or symptoms resolution in 16 (59%). The highest success rates were experienced by patients younger than 4, with long HSCR forms and with recurrent enterocolitis (75%, 100% and 100% of success rates, respectively). No major complications occurred. Minor complications were described by 7 patients (26%).

CONCLUSIONS

Intrasphincteric Botox injection proved to be feasible, safe and reasonably effective in children with HSCR and postoperative anal achalasia. Infants and toddlers with long HSCR forms and recurrent bouts of enterocolitis are those who would benefit most from this treatment.

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.

Hirschsprung-Associated Enterocolitis at a Referral Institution: A Retrospective Review

BACKGROUND

Hirschsprung-associated enterocolitis (HAEC) is the most common cause of morbidity and mortality amongst patients with Hirschsprung disease (HD); rectal Botulinum toxin (Botox) has been reported a possible prevention strategy. We aimed to evaluate our institution's historic cohort of HD patients, first to determine our incidence of HAEC and second to begin assessing the effect of Botox on HAEC incidence.

METHODS

Patients with HD seen at our institution between 2005 and 2019 were reviewed. Incidence of HD and frequencies of HAEC and Botox injections were tallied. Associations between initial Botox treatment or transition zone and HAEC incidence were evaluated.

RESULTS

We reviewed 221 patients; 200 were included for analysis. One hundred thirteen (56.5%) patients underwent primary pull-through at a median age of 24 days (IQR 91). Eighty-seven (43.5%) patients with initial ostomy had their intestinal continuity reestablished at a median of 318 days (IQR 595). Ninety-four (49.5%) experienced at least one episode of HAEC and 62 (66%) experienced multiple episodes of HAEC. Nineteen (9.6%) patients had total colonic HD and had an increased total incidence of HAEC compared to patients without total colonic HD (89% vs 44%, p < 0.001). Six (2.9%) patients received Botox injections at the time of pull-through or ostomy takedown; one experienced an episode of HAEC (versus 50.7% of the patients who were confirmed to have not received Botox injections at their surgery, p = 0.102).

CONCLUSION

Further prospective study on Botox's effect on Hirschsprung-associated enterocolitis is required and is the next step in our investigation.

LEVEL OF EVIDENCE

Level III.

The Deep Temporal Arteries: Anatomical Study with Application to Augmentations Procedures of the Temple

The aim of this study was to determine the anatomical features of the deep temporal arteries (DTAs) and thereby provide clinical information for the temple augmentation procedure. Forty-two adult hemifaces from 15 Korean and 6 Thai cadavers (12 males, 9 females; mean age at death, 79.6 years) with no history of trauma or surgical procedure on the temple area were used for anatomical study. A detailed dissection was performed to identify the locations of the anterior and posterior deep temporal arteries (ADTA and PDTA) with reference to the vertical plane passing through the zygomatic tubercle. Fifty-eight healthy Korean participants (31 males and 27 females; mean age, 24.7 years) were included in the ultrasonographic study. The distance from the bone to the DTAs was measured at the level of the zygomatic tubercle (H_Zt ) and the eyebrow (H_Eb ). The DTAs were not found within 7.2-12.6 mm posterior to the zygomatic tubercle; instead, the locations varied widely at the H_Eb . The distances between the bone and the ADTA were 1.7 ± 1.2 mm (mean ± SD) and 1.3 ± 0.8 mm, and those between the bone and the PDTA were 2.1 ± 1.2 mm and 2.0 ± 1.4 mm at H_Zt and H_Eb , respectively. Our findings indicate that at H_Zt , the area 1 cm posterior to the zygomatic tubercle may be a safe area for deep temple augmentation procedures. However, because the distribution patterns of the DTAs at H_Eb and depth of the DTAs are variable, additional care is required to minimize the risks of the procedure.

Clinical Characteristics of Adult Functional Constipation Patients with Rectoanal Areflexia and Their Response to Biofeedback Therapy

Background: The London Classification for anorectal physiological dysfunction specifically proposes rectoanal areflexia (RA), which means the absence of a rectoanal inhibitory reflex (RAIR) based on a manometric diagnosis. Although RA is not observed in healthy people, it can be found in adult patients with functional constipation (FC). This study describes the clinical manifestations of adult patients with FC and RA and their response to biofeedback therapy (BFT). Methods: This retrospective study reviewed the reports of high-resolution anorectal manometry (HR-ARM) and the efficacy of BFT in adult patients with FC. In addition, the Constipation Scoring System (CSS) scale, Patient Assessment of Constipation Symptoms (PAC-SYM) scale, Patient Assessment of Constipation Quality of Life (PAC-QOL) scale, Zung’s Self-Rating Anxiety Scale (SAS), Zung’s Self-Rating Depression Scale (SDS), balloon expulsion test (BET), and the use of laxatives were assessed. Results: A total of 257 adult patients diagnosed with FC were divided into the RA group (n = 89) and the RAIR group (n = 168). In the RA and RAIR groups, 60 (67.4%) and 117 (69.6%) patients, respectively, had dyssynergic defecation (DD) during simulated defecation. Type II pattern of dyssynergia was most frequently observed in both groups. Compared with the RA group, the RAIR group showed a higher CSS score, physical discomfort score, and prevalence of inadequate relaxation of the anal sphincter (p < 0.001, p = 0.036, and p = 0.017, respectively). The anxiety and depression scores were not different between the two groups. The proportion of patients using volumetric and stimulant laxatives and their combination was significantly higher in FC patients with RA, whereas the efficacy of BFT was significantly lower (p = 0.005, p < 0.001, p = 0.045, and p = 0.010, respectively). Conclusion: Adult FC patients with RA may suffer more severe constipation and have a lower efficacy of BFT compared with those with RAIR.

Anal Botulinum Toxin in Children with Hirschsprung Disease and Functional Constipation: A Prospective Cohort study

INTRODUCTION

 Anal sphincter botulinum toxin injections (BTIs) are used in the treatment of children with severe defecation disorders, including Hirschsprung disease (HD) and functional constipation (FC). Our objective was to evaluate the outcomes of BTI in these children.

MATERIALS AND METHODS

 We performed a prospective cohort study of children undergoing BTI from July 2018 to December 2018. We recorded perceived effect of the BTI, including effectiveness ranging from 0 (not at all effective) to 4 (extremely effective). In addition, we recorded symptoms and the Cleveland Clinic Constipation Score (CCCS). Data were collected at baseline and at 2 weeks, 2 months, and 4 months post-injection.

RESULTS

 Forty-two children (HD = 25, FC = 17) were included in the study (median age 4.3 years, IQR 2.4-7.2, 52% male). Twenty-two (88%) children with HD and eight (47%) children with FC had previously undergone a BTI. BTIs were perceived effective in 16 (76%) and 12 (71%) children with HD and eight (47%) and seven (47%) children with FC at 2 weeks and 2 months follow-up, respectively. Effectiveness was not rated differently between groups except at the 2-month follow-up, when patients with HD rated the BTI more effective compared to those with FC (median 2 [HD] vs. median 1 [FC], p = 0.022). Over the course of the study, 17/39 (44%) children reported self-limiting adverse effects such as fecal incontinence and pain at the injection site.

CONCLUSION

 Anal sphincter BTIs can be effective in the treatment of constipation in both HD and FC patients.

The utilization of botulinum toxin for Hirschsprung disease

Patients with Hirschsprung disease (HD) can struggle with persistent obstructive symptoms even after a successful pull-through. These symptoms lead to stasis of stool and can result in Hirschsprung associated enterocolitis (HAEC). Recurrent episodes of HAEC warrant further workup; if there are no signs of mechanical obstruction or an aganglionic pull-through, the use of botulinum toxin injections to the internal anal sphincter has been utilized to relieve these symptoms. In this review, we describe the variations in botulinum toxin injection use and describe ongoing studies to prevent obstructive symptoms and Hirschsprung-associated enterocolitis (HAEC). Botulinum toxin injection utilization has been described for obstructive symptoms after HD pull-through, in the setting of active HAEC, and has been proposed to be part of the treatment algorithm for prevention of HAEC after pull-through. Dosing utilized for the injections, along with the complications, are also described. Prospective, multi-institutional trials are needed to identify the effectiveness of botulinum toxin injections in the outpatient/prophylactic setting as current data suggest some benefits in preventing future obstructive symptoms; however, other studies have conflicting results.

The impact of botulinum injection for hospitalized children with Hirschsprung-associated enterocolitis

INTRODUCTION

Stasis from obstruction at the level of the internal anal sphincter (IAS) can lead to Hirschsprung-associated enterocolitis (HAEC) and may be improved by botulinum toxin (BT) injections. Our aim was to determine if BT injection during HAEC episodes decreased the number of recurrent HAEC episodes and/or increased the interval between readmissions.

METHODS

A retrospective review was performed of patients admitted for HAEC from January 2010 to December 2019. Demographics and outcomes of patients who received BT were compared to patients who did not receive BT during their hospital stay.

RESULTS

A total of 120 episodes of HAEC occurred in 40 patients; 30 patients (75%) were male, 7 (18%) had Trisomy 21 and 10 (25%) had long-segment disease. On multivariate analysis, patients who received BT during their inpatient HAEC episode had a longer median time between readmissions (p = 0.04) and trending toward an association with fewer readmissions prior to a follow-up clinic visit (p = 0.08).

CONCLUSION

The use of BT in HD patients hospitalized for HAEC is associated with an increased time between recurrent HAEC episodes and trended toward fewer recurrent episodes. The use of BT should be considered in the management of patients admitted with HAEC.

Outpatient Botulinum Injections for Early Obstructive Symptoms in Patients with Hirschsprung Disease

INTRODUCTION

Botulinum toxin (BT) injections may play a role in preventing Hirschsprung associated enterocolitis (HAEC) episodes related to internal anal sphincter (IAS dysfunction). Our aim was to determine the association of outpatient BT injections for early obstructive symptoms on the development of HAEC.

METHODS

A retrospective review of children who underwent definitive surgery for Hirschsprung disease (HSCR) from July 2010 - July 2020 was performed. The timing from pull-through to first HAEC episode and to first BT injection was recorded. Primary analysis focused on the rate of HAEC episodes and timing between episodes in patients who did and did not receive BT injections.

RESULTS

Eighty patients were included. Sixty patients (75%) were male, 15 (19%) were diagnosed with trisomy 21, and 58 (72.5%) had short-segment disease. The median time to pull-through was 150 days (IQR 16, 132). Eight patients (10%) had neither an episode of HAEC or BT injections and were not included in further analysis. Forty-six patients (64%) experienced at least one episode of HAEC, while 64 patients (89%) had at least one outpatient BT injection. Compared to patients who never received BT injections (n = 9) and those who developed HAEC prior to BT injections (n = 35), significantly fewer patients who received BT injections first (n = 28) developed enterocolitis (P < 0.001), with no patient developing more than one HAEC episode.

CONCLUSION

Outpatient BT is associated with decreased episodes of HAEC and increased interval between HAEC episodes requiring inpatient treatment. Scheduling outpatient BT injections to manage obstructive symptoms may be beneficial after pull-through for HSCR.

Reoperative techniques and management in Hirschsprung disease: a narrative review

The majority of children who undergo operative management for Hirschsprung disease have favorable results. A subset of patients, however, have long-term dysfunctional stooling, characterized by either frequent soiling or obstructive symptoms. The evaluation and management of a child with poor function after pull-through for Hirschsprung disease should be conducted by an experienced multidisciplinary team. A systematic workup is focused on detecting pathologic and anatomic causes of pull-through dysfunction. This includes an exam under anesthesia, pathologic confirmation including a repeat biopsy, and a contrast enema, with additional studies depending on the suspected etiology. Obstructive symptoms may be due to technique-specific types of mechanical obstruction, histopathologic obstruction, or dysmotility-each of which may benefit from reoperative surgery. The causes of soiling symptoms include loss of the dentate line and damage to the anal sphincter, which generally do not benefit from revision of the pull-through, and pseudo-incontinence, which may reveal underlying obstruction. A thorough understanding of the types of complications associated with various pull-through techniques aids in the evaluation of a child with postoperative dysfunction. Treatment is specifically tailored to the patient, guided by the etiology of the patient's symptoms, with options ranging from bowel management to redo pull-through procedure. This review details the workup and management of patients with complications after pull-through, with a focus on the perioperative management and technical considerations for those who require reoperation.

Intrasphincteric botulinum toxin injections for post-operative obstructive defecation problems in Hirschsprung disease: A retrospective observational study

BACKGROUND

Patients with Hirschsprung disease may have obstructive symptoms after resection of the aganglionic segment. Botulinum toxin (BT) injections can help improve faecal passage by relaxing the internal anal sphincter. This study assess effect of BT injections and aims to identify factors associated with receiving BT injections and favourable response to the first BT injection.

METHODS

A retrospective study was performed in a cohort of consecutive patients treated for Hirschsprung disease in our centre between 2003 and 2017. The indication for BT injections was obstructive defecation problems that were non-responsive to high-dose laxatives or rectal irrigation, or an episode of Hirschsprung-associated enterocolitis (HAEC). Effectiveness of BT injections was measured in terms of clinical improvement. Relationships between factors associated with receiving BT injections and with response to the first BT injection were tested with group comparison and logistic regression.

RESULTS

Forty-one out of 131 patients received BT injections (31%) with a median of two injections (range 1-11). All patients had obstructive defecation problems non-responsive to high-dose laxatives or rectal irrigation, two patient also had an episode of HAEC. Twenty-five out of 41 patients (61%) had clinical improvement after first injection. In 29 of the 41 patients (71%) spontaneous defecation or treatment with laxatives only was achieved. Adverse effects were seen in 12 out of 41 patients (29%) after 14 injections (16%), and consisted of anal pain, temporary loss of stools and dermatitis. Patients who received BT injections more often had long segment disease, more often required laxatives or rectal irrigation and had longer length of hospital stay, both after corrective surgery and in follow-up. None of the tested factors was associated with clinical improvement after first BT injection.

CONCLUSION

Our findings show that BT injections effectively treat obstructive defecation problems in the majority of patients with Hirschsprung disease with mild adverse effects.

LEVEL OF EVIDENCE

Level III.

Can botulinum toxin help in managing children with functional constipation and obstructed defecation?

BACKGROUND

Functional constipation (FC) is a common pediatric healthcare problem worldwide. Obstructed defection syndrome (ODS) is frequently presented with an inability to coordinate the bowel movement with pelvic floor muscles. Botulinum toxin (BT) intraanal sphincteric injection can improve the obstructed defecation by relaxing the anal sphincter and reducing the required force to propel the stools.

PURPOSE

This study aimed to compare the changes in Rintala scores (as a mean of assessing defecatory function), in children with FC and ODS, managed by BT injection, bowel management program (BMP), and senna based laxatives (SBL), versus a control group managed by BMP and SBL only.

METHODS

Prospective randomized controlled study, started at December 2017 on 40 pediatric patients, divided into 2 equal groups (group A: managed by BMP and SBL, group B: like group A with once intraanal sphincteric BT injection) suffering from FC, ODS, with contrast enema showing persistence of ≤90 rectoanal angle (RAA) even with trials of defecation. Patients were excluded if they have neuromuscular abnormalities, hypothyroidism, previous colorectal or anal surgery. Rintala score was assessed before treatment, at 2 months, and 6 months after management.

RESULTS

The study included 18 females (45%) and 22 males (55%). Group A had equal gender distribution and mean age of 6.9 years, while group B had 12 males with mean age of 7.35 years. The mean follow up period was 11.35 months in group A and 11.6 months in group B. Mean Rintala scores of both groups at initial presentation, 2 months and 6 months follow up were: group A: 9.10, 9.40, 10.90; group B: 9.30, 10.70, 11.05 respectively, and showed no statistically significant difference (p value: 0.884, 0.294, 0.923 respectively). No complications were detected from BT injection like allergic reactions, neuromuscular urinary or lower limbs disturbances.

CONCLUSION

Intraanal sphincteric injection of botulinum toxin by the mentioned technique and dose, did not result in additional defecatory functional improvement (when assessed by Rintala score) over the routine protocol (using bowel management program and laxatives) of managing functional constipation with obstructed defecation. ANNOUNCEMENT: a preliminary report of this work was presented in the 34th Egyptian pediatric surgery association (EPSA) meeting in Cairo in November 2019.

TYPE OF STUDY

Treatment/prospective study.

LEVEL OF EVIDENCE

Level I.

Impact of Botulinum Toxin on Hirschsprung-Associated Enterocolitis After Primary Pull-Through

BACKGROUND

Hirschsprung-associated enterocolitis (HAEC) is a serious potential complication after primary pull-through surgery for Hirschsprung's disease (HSCR). Administration of anal botulinum toxin (BT) injection may improve obstructive symptoms at the internal anal sphincter, leading to improved fecal passage. The timing of administration and effects on delay or prevention of HAEC are unknown. We hypothesized that BT administration increased the postoperative time to HAEC and aimed to investigate whether anal BT administration after primary pull-through surgery for HSCR is associated with increased time to inpatient HAEC admission development.

METHODS

We performed a retrospective cohort study examining children with HSCR at US children's hospitals from 2008 to 2018 using the Pediatric Health Information System database with an associated primary pull-through operation performed before 60 d of age. The intervention assessed was the administration of BT concerning the timing of primary pull-through, and two groups were identified: PRO (received BT at or after primary pull-through, before HAEC) and NOT (never received BT, or received BT after HAEC). The primary outcome was time from pull-through to the first HAEC admission. The Cox proportional hazards model was developed to examine the BT administration effect on the primary outcome after controlling for patient-level covariates.

RESULTS

We examined a total of 1439 children (67 in the PRO and 1372 in the NOT groups). A total of 308 (21.4%) developed at least one episode of HAEC, including 76 (5.3%) who had two or more episodes. Between 2008 and 2018, the frequency of BT administration has increased from three to 20 hospitals with a frequency of administration between 2.2% and 16.2%. Prophylactic BT (PRO) was not associated with increased time to HAEC event on adjusted analysis.

CONCLUSIONS

Among children with HSCR undergoing primary pull-through surgery, prophylactic BT administration did not demonstrate increased time to first HAEC event. A better-powered study with prophylactic BT is required to determine the effect on HAEC occurrence and timing.

LEVEL OF EVIDENCE

Level II (retrospective cohort study).

Inpatient management of Hirschsprung's associated enterocolitis treatment: the benefits of standardized care

INTRODUCTION

Patients with Hirschsprung's disease (HSCR) remain at risk of developing Hirschsprung-associated enterocolitis (HAEC) after surgical intervention. As inpatient management remains variable, our institution implemented an algorithm directed at standardizing treatment practices. This study aimed to compare the outcomes of patients pre- and post-algorithm.

METHODS

A retrospective review of patients admitted for HAEC was performed; January 2017-June 2018 encompassed the pre-implementation period, and October 2018-October 2019 was the post-implementation period. Demographics and outcomes were compared between the two groups.

RESULTS

Sixty-two episodes of HAEC occurred in 27 patients during the entire study period. Sixteen patients (59%) had more than one episode. The most common levels of the transition zone were the rectosigmoid (50%) and descending colon (27%). Following algorithm implementation, the median length of stay (2 vs. 7 days, p < 0.001), TPN duration (0 vs. 5.5 days, p < 0.001), and days to full enteral diet (6 days vs. 2 days, p < 0.001) decreased significantly. Readmission rates for recurrent enterocolitis were similar pre- and post-algorithm implementation.

CONCLUSION

The use of a standardized algorithm significantly decreases the length of stay and duration of intravenous antibiotic administration without increasing readmission rates, while still providing appropriate treatment for HAEC.

LEVEL OF EVIDENCE

III level.

TYPE OF STUDY

Retrospective comparative study.

Surgical Interventions for Functional Constipation: An Update

Chronic idiopathic constipation, also known as functional constipation, is defined as difficult and infrequent defecation without an identifiable organic cause. Medical management with laxatives is effective for the majority of constipated children. However there is a subset of patients who may need evaluation by a surgeon. As constipation progresses, it can lead to fecal retention and rectal and sigmoid distension, which impairs normal colorectal motility. Surgical interventions are influenced by the results of: a rectal biopsy, transit studies, the presence of megacolon/megarectum on contrast enema, the degree of soiling/incontinence, anorectal manometry findings, and colonic motility evaluation. In this review, we describe the different surgical options available (intestinal diversion, antegrade enemas, sacral nerve stimulation, colonic resections, and Botulinum toxin injection) and provide guidance on how to choose the best procedure for a given patient.

Comparison between Conventional Blind Injections and Ultrasound-Guided Injections of Botulinum Toxin Type A into the Masseter: A Clinical Trial

The aim of the study was to propose a more efficient and safer botulinum toxin type A (BoNT-A) injection method for the masseter by comparing the conventional blind injection and a novel ultrasonography (US)-guided injection technique in a clinical trial. The 40 masseters from 20 healthy young Korean volunteers (10 males and 10 females with a mean age of 25.6 years) were included in this prospective clinical trial. The BoNT-A (24 U) was injected into the masseter of each volunteer using the conventional blind and US-guided injection techniques on the left and right sides, respectively, and analyzed by US and three-dimensional (3D) facial scanning. One case of PMB (paradoxical masseteric bulging) was observed on the side where a conventional blind injection was performed, which disappeared after the compensational injection. The reduction in the thickness of the masseter in the resting state differed significantly at 1 month after the injection between the conventional blind injection group and the US-guided injection group by 12.38 ± 7.59% and 17.98 ± 9.65%, respectively (t(19) = 3.059, p = 0.007). The reduction in the facial contour also differed significantly at 1 month after the injection between the conventional blind injection group and the US-guided injection group by 1.95 ± 0.74 mm and 2.22 ± 0.84 mm, respectively (t(19) = 2.908, p = 0.009). The results of the study showed that the US-guided injection method that considers the deep inferior tendon by visualizing the masseter can prevent the PMB that can occur during a blind injection, and is also more effective.

Anal sphincter botulinum toxin injection in children with functional anorectal and colonic disorders: A large institutional study and review of the literature focusing on complications

BACKGROUND AND AIM

Botulinum toxin (botox) is a commonly used treatment for functional anorectal and colonic disorders. Although generally regarded as safe, complications associated with botox injection into the anal sphincters in children with severe defecation disorders are not well described. We aimed to review our institutional experience and the existing literature to better understand the safety of this practice.

METHODS

We performed a retrospective review of pediatric patients undergoing botox administration into the anal sphincter for treatment of a variety of defecation disorders between 2014 and 2018. Additionally, we performed a review of all published literature reporting complications from botox injection in this patient population.

RESULTS

881 patients ranging from 5 weeks to 19.7 years underwent a total of 1332 botox injections including our institution (332 patients/526 injections) and the reviewed series (549 patients/806 injections). Overall, complications were seen after 9 (0.7%) injections and included urinary incontinence (n = 5), pelvic muscle paresis (n = 2), perianal abscess (n = 1), pruritis ani (n = 1), and rectal prolapse (n = 1). Patient age, weight, and diagnosis were not associated with an increased rate of complication in our institutional experience. All complications were self-limited and did not require intervention. There were no episodes of systemic botulinum toxicity.

CONCLUSION

Botox injection into the anal sphincters is accepted practice in children with Hirschsprung disease, severe functional constipation, and internal anal sphincter achalasia and appears to be safe from this review. The precise dosing and age at which complications are more likely to arise could not be ascertained and require further study.

LEVEL OF EVIDENCE

IV TYPE OF STUDY: Retrospective cohort study.

Botulinum toxin injections after surgery for Hirschsprung disease: Systematic review and meta-analysis

BACKGROUND

A large proportion of patients with Hirschsprung disease experience persistent obstructive symptoms after corrective surgery. Persistent obstructive symptoms may result in faecal stasis that can develop into Hirschsprung-associated enterocolitis, a potential life-threatening condition. Important treatment to improve faecal passage is internal anal sphincter relaxation using botulinum toxin injections.

AIM

To give an overview of all empirical evidence on the effectiveness of botulinum toxin injections in patients with Hirschsprung disease.

METHODS

A systematic review and meta-analysis was done by searching PubMed, EMBASE and the Cochrane Library, using entry terms related to: (1) Hirschsprung disease; and (2) Botulinum toxin injections. 14 studies representing 278 patients met eligibility criteria. Data that were extracted were proportion of patients with improvement of obstructive symptoms or less enterocolitis after injection, proportion of patients with adverse effects and data on type botulinum toxin, mean dose, average age at first injection and patients with associated syndromes. Random-effects meta-analysis was used to aggregate effects and random-effects meta-regression was used to test for possible confounding factors.

RESULTS

Botulinum toxin injections are effective in treating obstructive symptoms in on average 66% of patients [event rate (ER) = 0.66, P = 0.004, I² = 49.5, n = 278 patients]. Type of botulinum toxin, average dose, average age at first injections and proportion of patients with associated syndromes were not predictive for this effect. Mean 7 duration of improvement after one botulinum toxin injections was 6.4 mo and patients needed on average 2.6 procedures. There was a significant higher response rate within one month after botulinum toxin injections compared to more than one month after Botulinum toxin injections (ER = 0.79, vs ER = 0.46, Q = 19.37, P < 0.001). Botulinum toxin injections were not effective in treating enterocolitis (ER 0.58, P = 0.65, I² = 71.0, n = 52 patients). There were adverse effects in on average 17% of patients (ER = 0.17, P < 0.001, I² = 52.1, n = 187 patients), varying from temporary incontinence to mild anal pain.

CONCLUSION

Findings from this systematic review and meta-analysis indicate that botulinum toxin injections are effective in treating obstructive symptoms and that adverse effects were present, but mild and temporary.

Neurostimulation-guided Anal Intrasphincteric Botulinum Toxin Injection in Children With Hirschsprung Disease

OBJECTIVES

In Hirschsprung disease (HD), despite successful surgical treatment, 50% of children experience long-term functional gastrointestinal problems, particularly chronic functional obstructive symptoms. We report our experience regarding clinical effects of neurostimulation-guided anal intrasphincteric botulinum toxin (BT) injections on postoperative obstructive symptoms attributed to a nonrelaxing anal sphincter complex in HD patients.

METHODS

In this monocenter cohort study, 15 HD patients with postoperative functional intestinal obstructive symptoms received neurostimulation-guided anal intrasphincteric BT injections. Short-, medium-, and long-term effects were evaluated. The Bristol stool form scale was used to assess stool consistency, and the Jorge-Wexner (JW) score to assess fecal continence.

RESULTS

The median age at first injection was 4 years. In the short-term, a significant improvement in stool consistency was noted in 12 of 14 patients (P = 0.0001) and JW score decreased for 14 of 15 patients (P = 0.001). In the medium-term, JW score significantly decreased for all patients (P = 0.0001), with an improvement of 50% or more for 10 patients (66.7%). In the long term, 83.3% of patients had normal stool consistency and JW score was <3 for all. Recurrent enterocolitis decreased from 86.7% to 8.3%. A complete resolution of all symptoms without further medication was observed in 66.7% of patients in the long term.

CONCLUSIONS

Intrasphincteric BT injection was a safe, effective, and durable option for the management of postoperative functional intestinal obstructive symptoms in HD. The use of neurostimulator guidance for specific delivery of BT to muscular fibers of nonrelaxing anal sphincter complex takes into consideration the variability of patient's anatomy secondary to curative surgery.

Innervation of the entire internal anal sphincter in a mouse model of Hirschsprung's disease: a first report

BACKGROUND

Impaired function of the internal anal sphincter (IAS) may be implicated in postoperative obstructed defecation (POD) that may complicate Hirschsprung's disease (HD) patients. While innervation of part of the IAS in HD has been reported, accurate details based on anatomic landmarks that can explain the clinical morbidity seen in POD are lacking, and there appear to be no studies that specifically document the innervation of the "entire" IAS in HD. We used endothelin receptor-B knockout mice to represent HD (HD-mice) and C57B6 wild mice as controls (C-mice) to investigate the innervation of the entire IAS to assess the pathophysiology of POD experimentally.

METHODS

The end-point of the longitudinal muscle layer was used to define the border between the IAS and the circular muscle layer (CML). Specimens of anorectum from HD- and C-mice were immunostained with PGP 9.5 and S100 as general nerve markers, nNOS and VIP as parasympathetic nerve markers, TH as a sympathetic nerve marker, and calretinin as a reliable diagnostic marker for HD. Immunostained cells/fibers were quantified using ImageJ.

RESULTS

On fluorescence microscopy, PGP 9.5, nNOS, and calretinin were significantly lower in the IAS of HD-mice than in C-mice (p < 0.05, respectively), while there were no significant differences between HD-mice and C-mice for S100, VIP, or TH.

CONCLUSION

We are the first to confirm that the expression of histochemical markers of innervation is abnormal throughout the "entire" IAS in HD-mice. Application of this finding may be beneficial for preventing POD and requires further research.

Constipation: Beyond the Old Paradigms

Constipation is a common problem in children. Although most children respond to conventional treatment, symptoms persist in a minority. For children with refractory constipation, anorectal and colonic manometry testing can identify a rectal evacuation disorder or colonic motility disorder and guide subsequent management. Novel medications used in adults with constipation are beginning to be used in children, with promising results. Biofeedback therapy and anal sphincter botulinum toxin injection can be considered for children with a rectal evacuation disorder. Surgical management of constipation includes the use of antegrade continence enemas, sacral nerve stimulation, and colonic resection.

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.

Bulbar Muscle Weakness in the Setting of Therapeutic Botulinum Injections

We present a case of new-onset bulbar muscle weakness in the setting of therapeutic botulinum injections for spasticity in a teenaged patient with cerebral palsy. Through a careful history, a systemic effect of the local injections was suspected, and the patient’s symptoms improved with a decrease in the dosing of the botulinum injections.