Application of Botulinum Neurotoxin in Male Sexual Dysfunction: Where Are We Now?

INTRODUCTION

Botulinum neurotoxin (BoNT) is a recognized therapeutic agent of modern medical care, routinely used to treat medical conditions affecting a variety of organ systems including the musculoskeletal, integumentary, and urological domains. Ongoing research is exploring BoNT's potential role as a therapeutic agent for a variety of male sexual pathologies.

OBJECTIVE

To review and analyze the literature regarding BoNT as a treatment option for male sexual dysfunction.

METHODS

A PubMed search was performed for English-language articles in peer-reviewed journals between 1970 and 2019 (with one article from 1897). Relevant articles referenced within these texts were also included. One article did not have an accompanied English full-text available. The following search terms were used: "Botox", "Botulinum toxin", "Botulinum toxin A", "Onabotulinum A", "Abobutlinum A", "BoNT", "BoNT-A", "Male sexual health", "Male sexual pathology", "Peyronie's disease", "Premature ejaculation", "Scrotal Pain", "Penile Retraction", "Scrotox", "Erectile Dysfunction", and "Botox in Urology".

RESULTS

There is interest in the potential role of BoNT in the treatment of male sexual pathologies. We identified studies that used BoNT to treat chronic scrotal content pain, premature ejaculation, erectile dysfunction, Peyronie's disease, penile retraction, and more. However, despite preclinical/clinical data indicating some potential efficacy and safety in these settings, a lack of robust clinical trial data has resulted in no current Food and Drug Administration-approved indications for the use of BoNT in the treatment of male sexual pathology. As a result, much of the current use of BoNT by today's providers is "off-label," and ongoing clinical trials aim to further elucidate the potential role of this therapeutic agent.

CONCLUSION

Current data suggest that BoNT could have a potential role as a treatment option for certain types of male sexual pathologies. However, more randomized controlled trial data regarding its long-term safety and efficacy are necessary before a widespread clinical adoption can take place. Reddy AG, Dick BP, Natale C, et al. Application of Botulinum Neurotoxin in Male Sexual Dysfunction: Where Are We Now?. J Sex Med 2021;9:320-330.

Evaluation of Botulinum Toxin A as an Optional Treatment for Atopic Dermatitis

OBJECTIVE: Botulinum toxin (BTX) A has different biological activities, including anti-inflammatory and antipruritic behavior. Studies on humans and animals have shown that BTX is efficient in treating itch caused by histamine, lichen simplex chronicus, psoriasis, rosacea, allergic rhinitis, and scar avoidance. OBJECTIVE: This study sought to assess the impact of BTX-A in patients with atopic dermatitis using scores of SCORAD and to identify parameters linked to greater improvements. METHODS: This was a prospective, intrapatient, left-to-right, randomized, placebo-controlled study of BTX-A for the treatment of atopic dermatitis. The study included 26 patients with atopic dermatitis (12 males and 14 females) with an average age of 37.8 years. Responses to therapy were assessed using SCORAD, Dermatology Quality of Life Index (DLQI), and the worldwide clinical reaction score evaluation. RESULTS: Mean SCORAD values dropped from 50.5 to 11 points (p<0.001); meanwhile, 64.1 percent of patients reported an excellent response, including 78.9 percent of patients with severe AD. The DLQI score fell by 10.15 points (43.5%) in patients treated with BTX-A. A statistically significant reduction in SCORAD and DLQI scores occurred relative to in the placebo group (p<0.001). CONCLUSION: Based on the results of this study, BTX-A appears to be a safe and effective therapy for atopic dermatitis of all grades (mild, moderate, and severe). However, BTX-A appears to be best suited for patients with severe atopic dermatitis.

Treatment methods for post-traumatic elbow stiffness caused by heterotopic ossification

HYPOTHESIS

Heterotopic ossification (HO) is a common complication of surgically treated elbow fractures that can inhibit range of motion and impair quality of life. Although there are many treatment methods for HO, there is a lack of consensus as to the best option. We hypothesized that contracture release combined with Botox injection would lead to improved functional outcome scores when compared with current treatment methods.

METHODS

A retrospective review was conducted of patients who presented to a single surgeon with HO secondary to elbow fracture between 2005 and 2018. A total of 59 patients were identified who met inclusion criteria. Data were classified into 3 groups: contracture release (control - CR), Botox injection with CR (Botox + CR), and radiation therapy with CR (CR + RT). Range of motion measurements were obtained, including flexion, extension, pronation, and supination.

RESULTS

A total of 30 patients (30 of 59, 50.8%) received CR, 6 (6 of 59, 9.2%) were treated with CR + RT, and 23 (23 of 59, 40.0%) had CR + Botox. There was a significant difference between pre- and postoperative arc of motion for both CR + RT (P < .01) and CR + Botox (P < .01). In addition, there was a significant difference in pre- and postoperative extension for patients who received intraoperative Botox injections (P < .05). There was no significant difference between pre- and postoperative motion nor extension in the CR group.

CONCLUSION

Intraoperative Botox injection with CR is an effective method in the treatment of post-traumatic elbow stiffness caused by HO.

The efficacy of onabotulinumtoxinA in patients with previous failed augmentation cystoplasty: Cohort series and literature review

AIMS

To investigate the role of onabotulinumtoxinA (BTX-A) injections in patients with failed augmentation cystoplasty for neuropathic or idiopathic detrusor overactivity (NDO or IDO).

METHODS

A retrospective review of all cystoplasty patients who underwent onabotulinumtoxinA injection at a tertiary center between 2008 and 2019 was performed. Details including indications and time from cystoplasty, video-urodynamic parameters, onabotulinumtoxinA dose, and clinical outcomes were analyzed. Telephone interview was performed for patients that requested repeat onabotulinumtoxinA injections. The interview included a modified PGIC7 and UDI6 questionnaires. A positive clinical response was considered improvement of overactive symptoms sufficient to merit repeat onabotulinumtoxinA injection and a modified PGIC7 of four or above.

RESULTS

Thirty patients were identified (11 men and 19 women). The indications for augmentation were IDO (n = 18) or NDO (n = 12). Mean age at the time of cystoplasty was 42 years (range, 10-61). Interval between cystoplasty and initial onabotulinumtoxinA was 98 months (range, 3-271). Video-urodynamics before onabotulinumtoxinA revealed low compliance in 13 patients, DO in 22 patients, and combined low compliance/DO in 10. The median maximum cystometric bladder capacity was 338 mL (range, 77-570 mL). Thirteen patients responded to onabotulinumtoxinA injections. Higher peak DO pressure was associated with a significantly higher chance that the patient would experience benefit from the injections P = .026). The patients that responded to onabotulinumtoxin A underwent a total of 115 procedures (mean, 8.8 injections) over a mean 88 months (range, 20-157 months).

CONCLUSIONS

Forty-three percent of patients responded well to intra-detrusor onabotulinumtoxinA injections. This avoided the need for more invasive surgery and had a positive impact on their quality of life.

Botox rechallenge-An additional tool in the management of an incompletely emptying bladder and inadequate overactive symptom control following sacral neuromodulation

Two female patients aged 70 and 72 with video-urodynamics-confirmed detrusor overactivity and detrusor underactivity (DO-DU) were treated. Patients were refractory to medical therapies and had previously failed intravesical botulinum toxin type A (BoNT-A) at other centers secondary to urinary retention and difficulty with self-catheterization. Placement of an Interstim II device (Medtronic, Minneapolis, Minnesota) for sacral neuromodulation (SNM) as alternative third-line treatment partially improved overactive bladder (OAB) symptoms while significantly improving voiding symptoms. Postvoid residual (PVR) of patients improved from a median of 118 mL (110-125 mL) to 20 mL (18-26 mL) and 213 mL (195-230 mL) to 70 mL (60-73 mL), respectively. Addition of medical therapies post SNM failed to modify OAB symptoms further and a rechallenge with dose-reduced BoNT-A was undertaken.OAB symptoms were significantly improved by addition of BoNT-A, while urinary retention was avoided (median PVR post BoNT-A 38 mL [34-40 mL] and 185 mL [150-205 mL], respectively). Reduction in incontinence pad use as well as resolution of nighttime incontinence in both patients and daytime incontinence in one patient was achieved. DO-DU patients treated by SNM who have improved bladder emptying (PVR <100 mL) but incomplete resolution of OAB symptoms should be trialed on adjunct medical therapies to improve OAB symptoms. If OAB symptoms are still inadequately controlled, consideration of a rechallenge with BoNT-A, particularly with dose reduction, appears to be efficacious and avoids symptomatic retention in this challenging cohort.

Trigonal-sparing versus trigonal-involved Botox injection for treatment of idiopathic overactive bladder: A randomized clinical trial

OBJECTIVE

To evaluate safety and efficacy of trigone-involved Botox injections in comparison with trigone-sparing injections in refractory idiopathic overactive bladder (OAB).

MATERIALS AND METHODS

One hundred and three patients randomly received a 100-IU intradetrusal injection of Botox either sparing the trigone (52 patients) or involving the trigone (51 patients). Patients were prospectively evaluated at 1, 3, and 6 months. Efficacy was evaluated by 3-day voiding diaries, OAB symptom score (OABSS), and pressure flow study. Any complications were recorded. An ascending cystogram was done at 3 months for detection of vesicoureteral reflux. Urinary tract infection (UTI) was estimated on urine culture basis. Primary outcome was the difference of total OABSS at 3 months.

RESULTS

The mean age ± SD was 34.3 ± 10 years (range 18-59 years). There was a reduction of episodes of all components of OAB in both groups in comparison with baseline by the end of the study but without significant difference between both groups. The trigonal-sparing group had less score of frequency compared with the trigonal-involved group throughout the study period (P < .05). There was no difference in OABSS at 3 months (1.5 ± 0.4 vs 1.6 ± 0.3, P .875). Two patients in the trigonal-involved group out of 51 (3.9%) were in need of clean intermittent catheterization because of voiding difficulty and a postvoid residual > 200 mL. There was a higher rate of UTI in the trigonal-involved group ranging from 5.6% up to 11.7% at each follow-up visit. No patient had reflux.

CONCLUSION

Trigone injections are not superior to trigone-sparing injections. On the contrary, the incidence of UTI and voiding difficulty were higher. The concept of reflux induced by trigonal injection has not been proven.

Single-event multilevel surgery, but not botulinum toxin injections normalize joint loading in cerebral palsy patients

BACKGROUND

Many patients with cerebral palsy present a pathologic gait pattern, which presumably induces aberrant musculoskeletal loading that interferes with natural bone growth, causing bone deformations on the long term. Botulinum toxin interventions and single-event multilevel surgeries are used to restore the gait pattern, assuming that a normal gait pattern restores musculoskeletal loading and thus prevents further bone deformation. However, it is unknown if these interventions are able to restore musculoskeletal loading. Hence, we investigated the impact of botulinum toxin injections and single-event multilevel surgery on musculoskeletal loading.

METHODS

Gait data collected in 93 children with bilateral cerebral palsy, which included pre- and post multi-level botulinum toxin (49 children) and single-event multilevel surgery (44 children) assessments, and 15 typically developing children were retrospectively processed using a musculoskeletal modelling workflow to calculate joint angles, moments, muscle and joint contact force magnitudes and orientations. Differences from the typically developing waveform were expressed by a root-mean square difference were compared using paired t-tests for each intervention separately (alpha <0.05).

FINDINGS

Botulinum toxin induced significant changes in the joint angles, but did not improve the muscle and joint contact forces. Single-event multilevel surgery induced significant kinematic and kinetic changes, which were associated with improved muscle and joint contact forces.

INTERPRETATION

The present results indicate that botulinum toxin injections were not able to restore normal gait kinematics nor musculoskeletal loading, whereas single-event multilevel surgery did successfully restore both. Therefore, single-event multilevel surgery might be protective against the re-occurrence of bone deformation on the longer term.

Practice Patterns and Barriers in Botulinum Toxin Injection for the Treatment of Voice Disorders

Laryngeal botulinum toxin injection is an important treatment modality for spasmodic dysphonia and other laryngeal disorders. We sought to compare usage patterns of laryngeal botulinum toxin injections for voice disorders and to identify and quantify inefficiencies and barriers in providing this treatment. A 26 item survey was written and approved for distribution by the American Academy of Otolaryngology-Head and Neck Surgery and the National Spasmodic Dysphonia Association. It was distributed to Otolaryngologists who perform laryngeal botulinum toxin injections via the e-mail lists of the National Spasmodic Dysphonia Association provider database, American Academy of Otolaryngology-Head and Neck Surgery Voice Committee and the American Laryngological Association Neurolaryngology Study Group. There were 81 survey participants who collectively reported performing >1700 laryngeal botulinum toxin injections for voice disorders monthly (Mean = 21.5 pts/month). Regarding botulinum toxin A (BtxA) vial use, 54% of participants reported using multiple doses per vial for different patients during a single clinic day, while 14% reported using pharmacy predrawn single use aliquots. A combination of usage practices was reported by 7% of participants. Using an individual vial per patient and discarding the unused remainder was reported by 26% of participants with an associated annual cost in wasted BtxA of $84,300 per physician. There is wide variation in injection practices regarding management of BtxA vials and adherence to an individual vial per patient policy is associated with significant waste of health care resources. Alternative approaches to BtxA vial use could positively impact health care resource utilization.

The Effects of Self-Esteem, Coping, and Voice-Related Quality of Life on Communicative Participation Before and After BOTOX® Treatment for Spasmodic Dysphonia

OBJECTIVES/HYPOTHESIS

The purpose of this study was to (1) investigate the percent change in communicative participation in individuals with spasmodic dysphonia (SD) pre- and post-BOTOX® treatment; and (2) to investigate if percent change in communicative participation is predicted by change in self-esteem, coping, and/or Voice-Related Quality of Life (V-RQOL) pre- and post-BOTOX® treatment.

STUDY DESIGN/METHODS

A cross-sectional study of 49 patients was conducted across three clinics, with each participant completing the Rosenberg Self-Esteem Scale, the Voice Disability Coping Questionnaire (VDCQ), the V-RQOL instrument, and the Communication Participation Item Bank (CPIB) before BOTOX® treatment and 10-14 days following BOTOX® treatment.

DATA ANALYSIS

For Research Question 1, a paired t test was applied to test the equality of means for CPIB and to test the pre-post changes among other composite measurements before and after the BOTOX® treatment. For Research Question 2, a multivariable linear regression model was applied with percent change in CPIB as a main outcome, and change in Rosenberg Self-Esteem Scale, VDCQ, and the V-RQOL as independent variables (or covariates) in order to test the associations.

RESULTS

The results indicated that pre- and post-BOTOX® measures of communicative participation are not statistically significantly different among the participants with SD. There was a strong positive correlation between change in coping and voice-related QOL.

CONCLUSIONS

A better understanding of the relationship between communicative participation and voice-related QOL is warranted. Item analysis of the V-RQOL and the VDCQ may illustrate coping strategies and functional impairments and provide further information regarding highly variable communicative participation among individuals with SD.

Paradoxical Vocal Fold Movement: A Retrospective Analysis

BACKGROUND

Paradoxical vocal fold motion (PVFM) is a disorder in which the vocal folds adduct inappropriately during inspiration resulting in episodic dyspnea and sometimes respiratory distress. Diagnosis is obtained through careful history, physical examination, flexible laryngoscopic examination with provocative maneuvers, and laryngeal electromyography. The pathogenesis and clinical findings of this disorder are not known.

OBJECTIVES

To determine characteristics of patients with confirmed PVFM and to evaluate efficacy of current treatments.

METHODS

A retrospective chart review of the patients with PVFM who presented at a quaternary care laryngology office between January 1, 2007 and August 31, 2019 was performed. Comorbidities, laboratories tests, imaging, 24-hours pH impedance testing, and laryngeal EMG results were analyzed. Dyspnea Index questionnaire before and after treatment was used to evaluate the efficiency of treatments for PVFM.

RESULTS

The average age of the 40 patients was 30.25 years. Forty-five percent of patients were under the age of 18, and 80% were female. Twenty-five percent of patients were serious athletes, and 40% of patients were students. Sixty-five percent had a previous diagnosis of asthma. One third of patients had concurrent psychiatric diagnosis. There was no family history of PVFM in the cohort. There were no other common findings. Treatment for laryngopharyngeal reflux (LPR) was used only when there was evidence of LPR; and 93% of our 40 patients received LPR treatment. Ninety percent of patients who received botulinum toxin, voice therapy (VT), and LPR treatment had subjective improvement. Patients with just VT and LPR treatment had a 43% subjective improvement rate; and the difference was statistically significant at P of 0.021. There was no statistical difference between VT and LPR treatment versus VT or LPR treatment alone.

CONCLUSION

Botulinum toxin, VT, and LPR treatment regimen is currently the most effective management for patients with paradoxical vocal fold movement disorder. More research is needed to determine the etiology of this disorder.

Delay in OnabotulinumtoxinA Treatment During the COVID-19 Pandemic-Perspectives from a Virus Hotspot

The COVID‐19 pandemic has undoubtedly changed our practice of medicine. With our collective resources and attention focused on caring for those afflicted with the disease, other medical conditions have temporarily but understandably faced constraint. For migraine patients who often require in‐person visits for infusions and procedures, this has become particularly challenging. Here, we share our experience in navigating this exigency amidst a local surge of COVID‐19.

Systemic Botulism Toxicity Caused by Pyloric Botox Injection to Treat Gastroparesis

Systemic botulism resulting from therapeutic Botox (OnabotulinumtoxinA) injection has been rarely reported, and never in the context of pylorus injection to treat gastroparesis. We report the case of a 27-year-old female with Emery-Dreifuss muscular dystrophy who developed severe systemic botulism toxicity following the intrapyloric injection of 100 units of Botox to treat gastroparesis. The patient eventually made a full recovery.

Perspectives for the use of therapeutic Botulinum toxin as a multifaceted candidate drug to attenuate COVID-19

The recent outbreak of coronavirus disease (COVID-19) resulting from a distinctive severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) continues to evolve in many countries and pose life-threatening clinical issues to global public health. While the lungs are the primary target for the SARS-CoV-2-mediated pathological consequence, the virus appears to invade the brain and cause unpredicted neurological deficits. In the later stage, COVID-19 can progress to pneumonia, acute respiratory failure, neurodegeneration and multi-organ dysfunctions leading to death. Though a significant portion of individuals with COVID-19 has been recovering from clinical symptoms, the pathological impact of the SARS-CoV-2 infection on the structural and functional properties of the lungs, heart, brain and other organs at the post-recovery state remains unknown. Presently, there is an urgent need for a remedial measure to combat this devastating COVID-19. Botulinum toxins (BoNTs) are potent neurotoxins that can induce paralysis of muscle and acute respiratory arrest in humans. However, a mild dose of the purified form of BoNT has been known to attenuate chronic cough, dyspnoea, pneumonia, acute respiratory failure, abnormal circulation, cardiac defects and various neurological deficits that have been recognised as the prominent clinical symptoms of COVID-19. Considering the fact, this review article provides 1) an overview of the SARS-CoV-2 mediated pathological impact on the lungs, heart and brain, 2) signifies the therapeutic uses of BoNTs against pulmonary failure, cardiac arrest and neurological deficits, and 3) emphasize the rationality for the possible use of BoNT to prevent SARS-CoV-2 infection and manage COVID-19.

The Positive Effects of a Calorie-Restricting High-Protein Diet Combined with Intragastric Botulinum Toxin Type A Application Among Morbidly Obese Patients: A Prospective, Observational Analysis of Eighty-Seven Grade 2 Obese Patients

PURPOSE

Many studies evaluating the effect of intragastric botulinum toxin type A injection (IG-BTxA) for the treatment of obesity have been published. However, none of these studies combined this procedure with a calorie-restricting high-protein diet. Herein, we aimed to evaluate the effects of IG-BTxA application combined with a calorie-restricting high-protein diet.

MATERIALS AND METHODS

This prospective cohort study is conducted with eighty-seven grade 2 obese patients treated between January 2019 and August 2019. Group 1: IG-BTxA + refused to consult the dietitian; group 2: IG-BTxA + get calorie-restricting high-protein diet; group 3: only get a calorie-restricting high-protein diet. Loss of weight, treatment adaptation (visual analog scale score), the status and changes of comorbid conditions, and changes in eating behaviors (Self-Regulation of Eating Behaviour Questionnaire score) were assessed.

RESULTS

Loss of weight, treatment adaptation, and positive behavioral change in eating preferences were significantly higher in group 2 (p = 0.01; p = 0.001; p < 0.01, respectively). Additionally, the decrease in medication requirement for diabetes and hypertension was higher in group 2 (p < 0.05).

CONCLUSION

IG-BTxA application before calorie-restricting high-protein diet facilitates adaptation to the new diet style and helps to lose weight faster in grade 2 obese patients. Also, more positive results were achieved in terms of controlling comorbid diseases.

Botox and Dermal Fillers: Review and Its Role in the Dental Office

For the general dentist, the use of BTA and dermal fillers confers the ability to exert control over the soft tissues surrounding the mouth to better create a harmonious smile. The injection of BTA and fillers into the facial musculature and dermis requires a level of finesse to achieve the desired outcomes. A sound understanding of the mechanisms of action and the ability to manage potential complications are also necessary, because the dentist administering BTA and dermal fillers must be competent to the same level as other providers who have traditionally been the gatekeepers of such agents.

Application of Botulinum Neurotoxin in Female Sexual and Genitourinary Dysfunction: A Review of Current Practices

INTRODUCTION

The past 2 decades have witnessed an increased amount of research into botulinum neurotoxin (BoNT) as a treatment for various forms of sexual dysfunction and pain syndromes refractory to other medical therapy. BoNT is postulated to reduce pain sensation by inhibiting neuropeptide release in the presynaptic neuron. Dyspareunia, vaginismus, vestibulodynia, and persistent genital arousal disorder are female sexual dysfunctions with cryptic pathophysiology and limited treatment options. BoNT has emerged as a potential treatment for many of these afflictions in women.

OBJECTIVES

To review the literature regarding BoNT as a treatment for female sexual and genitourinary dysfunction.

METHODS

A PubMed search for English-language articles was performed using the following terms: "Botox," "botulinum toxin," "botulinum toxin A," "Onabotulinum A," "Abobutlinum A," "BoNT," and "BoNT-A." The main outcomes measured by each study were resolution of dysfunction. This entailed reduction of pain with intercourse for dyspareunia, reduction of pain for vestibulodynia, decreased arousal for persistent genital arousal disorder, and ability to tolerate penetration for vaginismus.

RESULTS

A total of 12 human studies that evaluated BoNT as a treatment for female sexual disorders were included. Study types included prospective, retrospective, cohort, pilot, and open-label.

CONCLUSION

There is growing evidence suggesting that BoNT is a safe and efficacious treatment option for female patients suffering from various sexual and genitourinary disorders. However, more research is needed to develop a better understanding of the mechanisms through which BoNT treats these disorders. Dick B, Natale C, Reddy A, et al. Application of Botulinum Neurotoxin in Female Sexual and Genitourinary Dysfunction: A Review of Current Practices. Sex Med 2021;9:57-63.

Swallowing disorders following free jejunal flap reconstruction of circumferential pharyngeal defect: Does Botox help?

OBJECTIVES

Free jejunal flap for circumferential pharyngeal reconstruction is associated with late-onset dysphagia, regurgitation and prolonged transit time. This study aims to assess the feasibility and efficacy of Botulinum toxin A (Botox) in alleviating such swallowing dysfunction.

MATERIALS AND METHODS

Twenty-six consecutive patients underwent free jejunal flap for circumferential pharyngeal reconstruction between January 2012 and December 2018. Outcomes were compared at 6, 12 and 24 months.

RESULTS

In the non-Botox group (n = 13), video-fluoroscopic and manometry studies demonstrated asynchronous contractions and retrograde propulsion. All patients complained of nasal regurgitation on thin fluids at 6, 12 and 24 months. Bolus residue accumulation along jejunal mucosal folds resulted in prolonged transit time. In the Botox group (n = 13), amplitude of asynchronous contractions were lower: 25.4 mmHg vs. 52.1 mmHg (p = 0.037) for thin fluids at 12 months. Three patients complained of nasal regurgitation on thin fluids at 6 months. All 3 were asymptomatic at 12 months. Transit time was shortened overall. Functional Oral Intake Scale was higher. MD Anderson Dysphagia Inventory global (72.5% vs 45.7%, p = 0.003) and functional (62.0% vs 40.6%, p = 0.012) subscales were significantly improved at 24 months.

CONCLUSION

Botox safely and effectively alleviates swallowing dysfunction associated with free jejunal flap for circumferential pharyngeal reconstruction.

Manufacturing and Clinical Formulations of Botulinum Neurotoxins

Botulinum Neurotoxins have always existed in nature, but its paralytic effect on humans due to the consumption of poorly preserved food was not recognized until 18th century. There are 8 serotypes of botulinum neurotoxins (A, B, C, D, E, F, G, H). Serotype A have been the most recognized one and was initially developed for large scale production in 1940's. The first batch for clinical use was produced by Edward Schantz, who collaborated with Dr. Alan Scott, an ophthalmologist, evaluating botulinum neurotoxin to treat strabismus. The process Schantz used had variability and led to inconsistent batch production. However, this process is still used by various manufacturers of commercial botulinum neurotoxin products as the foundation. These manufacturers have refined the manufacturing of botulinum neurotoxins by implementing new advanced techniques, including better potency assays. Despite the improvements in the manufacturing process, botulinum neurotoxins are still one of the most potent molecules and therefore, require special handing and additional safety/security measurements during production.

Botox injection into the lower esophageal sphincter induces hiatal paralysis and gastroesophageal reflux

Endoscopic intrasphincteric injection of Botox (ISIB) is used routinely for the treatment of achalasia esophagus and other spastic motor disorders. Studies show that the ISIB reduces the smooth muscle lower esophageal sphincter (LES) pressure. The esophageal hiatus, formed by the right crus of diaphragm, surrounds the cranial half of the LES and works like an external LES. We studied the effects of ISIB on the LES and hiatal contraction and gastroesophageal reflux (GER). Fourteen patients treated with ISIB were studied. Esophageal manometry-impedance recordings were performed before and after the ISIB. Hiatal contraction was assessed during tidal inspiration, forced inspiration, Müller's maneuver, and straight leg raise. In 6 subjects, the manometry were repeated 6-12 mo after the ISIB. The esophagogastric junction (EGJ) pressure was measured at end expiration (LES pressure) and at the peak of maneuvers (hiatal contraction). Transdiaphragmatic pressure (pdi; force of diaphragmatic contraction) was measured at the peak of forced inspiration. GER was measured from the impedance recordings. The EGJ pressure at end expiration (LES pressure) decreased significantly after the Botox injection. The peak EGJ pressure at tidal inspiration, forced inspiration, Müller's maneuver, and straight leg raise was also dramatically reduced by the ISIB. There was no effect of Botox on the pdi during forced inspiration. Seven of 10 subjects demonstrated GER during maneuvers following the ISIB. Six to 12 mo after ISIB, the LES and hiatal contraction pressure returned to the pre-ISIB levels. ISIB, in addition to decreasing LES pressure, paralyzes the esophageal hiatus (crural diaphragm) and induces GER.NEW & NOTEWORTHY The sphincter mechanism at the lower end of the esophagus comprises smooth muscle lower esophageal sphincter (LES) and skeletal muscle crural diaphragm (hiatus). Current thinking is that the endoscopic intrasphincteric injection of Botox (ISIB), used routinely for the treatment of achalasia esophagus, reduces LES pressure. Our study shows that ISIB, even though injected into the LES, diffuses into the hiatus and causes its paralysis. These findings emphasize the importance of esophageal hiatus as an important component of the antireflux barrier and that the ISIB is refluxogenic.

Botulinum toxin type A for the treatment of muscle contractures secondary to acute spinal cord injury in a young cat

Case summary

A 4-month-old male entire domestic shorthair cat presented for sudden onset of right thoracic monoparesis following a fall; within 18 h, the clinical signs progressed to non-ambulatory right hemiplegia with absent sensation in the distal right thoracic limb and left hemiparesis. MRI revealed changes consistent with a C6-C7 acute non-compressive nucleus pulposus extrusion with suspected secondary C5-C7 spinal cord haemorrhage. Rehabilitation exercises were started immediately after the diagnosis of acute spinal cord trauma. Sensation in the right thoracic limb improved and, with the help of a splint applied to that limb, the cat was ambulatory on all four limbs. Unfortunately, clinical signs started to progress over the course of 10 days. The cat developed progressive discomfort on manipulation of the right elbow and carpus, and a hyperflexion of the right carpus. Radiographs revealed no skeletal abnormalities. Muscle contractures were suspected. Under general anaesthesia the triceps and flexor muscles of the carpus and digits were injected with a total of 100 U of botulinum toxin type A (BTX-A). No complications were associated with the procedure and 24 h after the injection the carpal hyperflexion resolved.

Relevance and novel information

The use of BTX-A to treat muscle contractures in human medicine is an established and increasingly used technique. For example, in subacute stroke patients with a non-functional arm, BTX-A forearm injection appears to prevent disabling finger stiffness, likely by minimising the development of contractures. Here, we demonstrate that intramuscular BTX-A is an effective treatment for acquired muscle contractures in a cat.

Classification of Hypertrophic Gastrocnemius Muscle and Its Treatment with Botulinum Toxin A

BACKGROUND

Treatments including selective neurectomy, muscle resections and botulinum toxin A (BTX) injections have been used to improve the stocky appearance of calves. BTX injection has the advantages of high efficiency and is almost noninvasive. However, criterion standards of injection are still missing.

OBJECTIVE

We aimed to establish a method to classify the hypertrophic calf for a personalized treatment and set up an injection protocol based on the findings.

METHODS

Three-dimensional CT reconstruction was used to measure the thickness and cross-sectional area of the triceps surae. B-mode ultrasound and palpation were used to evaluate the muscle thickness and determine the dosage. Patients were followed 3 and 6 months after the treatment.

RESULTS

A total of 112 legs were classified into three degrees of thickness (< 15 mm, 15-25 mm and > 25 mm). Twenty-seven subjects were treated with an individualized BTX (100-300 U). Maximal circumference decreased 0.33 ± 0.00 cm after 3 month (p < 0.05) and 0.67 ± 0.11 cm after 6 months (p < 0.01). The angulated calf contour was improved. No severe side effects were reported.

CONCLUSIONS

Localizing and dosage are the key points when applying BTX. Dosage should be decided by muscle thickness instead of circumference. BTX treatment improves the prominent contour of the calf rather than reducing the volume.

LEVEL OF EVIDENCE IV

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Real-World Safety And Effectiveness Of OnabotulinumtoxinA Treatment Of Crow's Feet Lines And Glabellar Lines: Results Of A Korean Postmarketing Surveillance Study

Purpose

OnabotulinumtoxinA is approved in the Republic of Korea for the treatment of moderate-to-severe crow's feet lines (CFL) and glabellar lines (GL), separately or in combination. We assessed safety and effectiveness of onabotulinumtoxinA in real-world clinical practice.

Patient and methods

This 4-year postmarketing surveillance study was conducted in the Republic of Korea in subjects with moderate-to-severe CFL. Subjects aged 18 to 75 years received onabotulinumtoxinA injections for CFL alone or in combination with GL. Safety assessments included adverse events (AEs), serious AEs (SAEs), and unexpected AEs (not noted in Korean prescribing information). Investigators assessed effectiveness via change from baseline in CFL.

Results

The full analysis set comprised 695 subjects; 667 were in the safety set and 376 in the effectiveness set. In the safety set, mean ± SD age was 40.9±13.0 years; most subjects (87.3%) were female. More subjects were treated for CFL (69.9%) than CFL and GL simultaneously (30.1%). Eleven subjects experienced 14 AEs; 12 were mild in severity and 11 resolved without sequelae. Two cases of injection site pain in 2 subjects each were deemed possibly related to onabotulinumtoxinA. One unexpected SAE (acute renal failure) occurred in 1 subject (0.15%). All unexpected AEs (n=4) were mild and considered unrelated to treatment. Overall change from baseline showed CFL was improved in 375 subjects (99.7%) and unchanged in 1 subject (0.3%).

Conclusion

OnabotulinumtoxinA was well tolerated and effective for treatment of CFL with or without GL in a real-world Korean population. No new safety concerns were identified.

Botulinum toxin A versus electrogalvanic stimulation for levator ani syndrome: is one a more effective therapy?

BACKGROUND

Levator ani syndrome (LAS) is a functional disorder that can be a challenge to treat. LAS that is refractory to medical management may be treated with electrogalvanic stimulation (EGS) or Botulinum toxin A (BTX) injection. The aim of the present study was to evaluate the outcomes associated with both EGS and BTX in patients with medically refectory LAS to determine if either demonstrate a long-term benefit or whether one treatment is better than the other.

METHODS

A retrospective study was performed on consecutive patients with LAS treated with BTX or EGS at our institute. Patients were identified from a prospectively maintained database. The study time frame was 6 years.

RESULTS

One hundred and twenty patients [80 females, mean age 52 years (range 21-84, SD 15.8)] were treated for medically refractory LAS: 102 with BTX and 18 with EGS. With EGS, 28.6% of patients reported a complete response, 14.3% reported a partial response and 57.1% reported no response to treatment. With BTX, 35.5% of patients reported a complete response, 19.7% reported a partial response and 44.7% reported no response to treatment. There was no difference between BTX and EGS with regard to treatment response. Patients who had BTX were more likely to report a short-term benefit in treatment when compared to those patients who had EGS (p = 0.002). This difference between reported outcome to BTX and EGS treatments did not sustain in the long term (p = 0.2).

CONCLUSIONS

Both BTX and EGS are to some extent effective at resolving symptoms of LAS. In the short term, BTX appears to be more effective. Neither treatment sustains its benefit in the long term.

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.