Therapy of Sialorrhea with Botulinum Neurotoxin

Does injection of botulinum toxin to salivary glands require ultrasound guidance?

INTRODUCTION

Injection of botulinum toxin into salivary glands is a well-established treatment for sialorrhea in children, but the absolute need for radiological guidance has not been tested.

METHODS

Single-centre study in which clinicians of varying seniority attempted blind injection of salivary glands, after which their position within or outside the gland was confirmed by ultrasound guidance before the injection is administered.

RESULTS

117 patients underwent botulinum toxin of salivary glands between November 2008 and August 2023, with 459 glands injected in total. 24 (5 %) glands were injected by medical students, 32 (7 %) by junior trainees (foundation doctors or senior house officers), 343 (75 %) by registrars or senior fellows and 36 (8 %) by consultants. 160 (68 %) of injections to the parotid gland were on target, and 74 (32 %) submandibular gland were on target (P < 0.01). No differences were detected on likelihood of success depending on seniority of practitioner, age of patient or hand dominance.

CONCLUSION

Ultrasound guidance ought to be recommended for injection of botulinum toxin into salivary glands regardless of the seniority of the practitioner.

Using Neuromodulators for Salivary, Eccrine, and Apocrine Gland Disorders

BACKGROUND

Sialorrhea, hyperhidrosis, bromhidrosis, and chromhidrosis are common glandular disorders that substantially impact patients' health and quality of life. Botulinum toxin can safely and temporarily decrease gland secretions by targeting the parasympathetic cholinergic neurons, resulting in diminished saliva and sweat production.

OBJECTIVE

The objective of this article is to describe the applications of neuromodulators for the treatment of salivary, eccrine, and apocrine glands.

METHODS

PubMed was searched from inception to February 1, 2024 using search terms "neurotoxin," "botulinum toxin," "sialorrhea," "hyperhidrosis," "bromhidrosis," and "chromhidrosis."

RESULTS

Incobotulinumtoxin A and Rimabotulinumtoxin B are approved by the FDA for the treatment of sialorrhea. Onabotulinumtoxin A is the only FDA-approved botulinum toxin for axillary hyperhidrosis and is used off-label for hyperhidrosis of nonaxillary sites, bromhidrosis, and chromhidrosis. Compared to botulinum toxin serotype A, serotype B has been associated with more immunogenicity, which may have implications for patients requiring long-term treatment for chronic glandular disorders.

CONCLUSION

Neuromodulators are safe and effective for the noninvasive treatment of excess gland activity and can improve patients' quality of life. While substantial literature supports botulinum toxin treatments for hyperhidrosis, further studies are needed to characterize standard dosing and administration techniques for sialorrhea, bromhidrosis, and chromhidrosis.

Real-World Observational Analysis of Clinical Characteristics and Treatment Patterns of Patients with Chronic Sialorrhea

Chronic sialorrhea is a condition characterized by excessive drooling, often associated with neurological and neuromuscular disorders such as Parkinson's disease, cerebral palsy, and stroke. Despite its prevalence, it remains underdiagnosed and poorly understood, leading to a lack of comprehensive data on patient demographics, clinical characteristics, and treatment patterns. This study aimed to help fill these existing gaps by analyzing real-world data using Optum's de-identified Clinformatics® Data Mart Database. Patients were required to have a diagnosis indicative of sialorrhea plus evidence of sialorrhea treatment between 1/1/2007 and 5/31/2022. Two cohorts were analyzed: patients with evidence of newly diagnosed sialorrhea and associated treatment, and sialorrhea patients initiating incobotulinumtoxinA. Clinical characteristics, comorbidities, symptoms, and treatment utilization were described before and after diagnosis and incobotulinumtoxinA initiation. No formal statistical comparisons were performed. Patients were predominantly aged 65 or older, male, and non-Hispanic white. Parkinson's disease and cerebral palsy were the most common comorbidities among adults and children, respectively. Treatment patterns suggest that anticholinergics are more commonly used than botulinum toxin therapy. The findings offer valuable information for improving diagnosis and treatment approaches and suggest a need for further research into treatment effectiveness, safety, and disease burden.

Therapy with botulinum neurotoxin for Parkinson's disease

Botulinum neurotoxin (BoNT) has been in use since the 1970's. Its effect is reached mainly by inhibiting the release of acetylcholine in the synaptic gap of motor neurons or at the motor end plate and the parasympathetic ganglia. In the case of Parkinson's disease, it is used to treat several motor and non-motor symptoms. Within recent years increasingly numerous possible fields of application of BoNT have been found for the treatment of Parkinson's disease, and for some specific symptoms it has in fact become the therapy of choice, while for others it is but one of the therapeutic options that come into consideration when others are not sufficiently effective. In the following, we intend to outline the indications, the possible side effects and also the approvals for therapies with botulinum toxin in the primary and secondary symptoms of Parkinson's disease.

Use of botox for sialorrhea and dysphagia in the neonatal population

INTRODUCTION

Botox is frequently used for sialorrhea in patients with compromised airways and those with etiologies causing difficulty with secretion management (i.e. strokes, neurologic disorders, etc.). There are no published studies regarding the use of botulinum toxin (BoNT) in the neonate population. We aim to discuss our experience and safety of BoNT use in the neonate population in regards to alleviating secretion management and airway protection.

METHODS

Retrospective review of neonates admitted to the neonatal intensive care unit (NICU) ≤12 months of age who received BoNT injection to submandibular (SMG) and parotid (PG) glands for sialorrhea/dysphagia. BoNT was administered under ultrasound (u/s) guidance by interventional radiology.

RESULTS

6 children were examined. 2 (33 %) were male. Avg NICU stay was 87.5 ± 33.1 days. 2 underwent surgical airway intervention prior to injection. Mean age at initial BoNT was 1.5 ± 0.7 months. Avg weight at injection was 4 ± 1.1 kg. Each PG and SMG were injected in 5/6 cases. Bilateral SMG were unidentified on u/s in 1 case and thus not injected. Dose range injected per gland was 5-15u. 100 % required tube feeds, 50 % with tubes distal to stomach (NJT/NDT). 83 % were completely NPO prior to injection and there was no noted clinical improvement in oral skills post injection. All had noted desats/apneas prior to injection and 83 % had reported decreased events post injection. 50 % had reported decrease O2 requirements and frequent suctioning 2wks after injection, however 2 (33 %) required surgical airway intervention after injection (trach, SGP/MDO). 4/6 (67 %) trialed medical therapy, anticholinergics being the most common. 50 % underwent 2nd injection (age = 6.5 ± 0.3 months) avg. 4.7 ± 0.7mo after 1st injection, and the same 3pts underwent 3rd injection (age = 12.5 ± 2.4 months) avg. 6.1 ± 2.5mo after 2nd injection. 1 pt. had a total 6 injections. There were no injection related complications.

CONCLUSION

BoNT injection is a safe, non-invasive alterative for management of sialorrhea in neonates. Further extensive study needs to be performed to identify the optimal dose per gland in this population.

Recent Developments in Engineering Non-Paralytic Botulinum Molecules for Therapeutic Applications

This review discusses the expanding application of botulinum neurotoxin in treating neurological conditions. The article specifically explores novel approaches to using non-paralytic botulinum molecules. These new molecules, such as BiTox or el-iBoNT, offer an alternative for patients who face limitations in using paralytic forms of botulinum neurotoxin due to concerns about muscle function loss. We highlight the research findings that confirm not only the effectiveness of these molecules but also their reduced paralytic effect. We also discuss a potential cause for the diminished paralytic action of these molecules, specifically changes in the spatial parameters of the new botulinum molecules. In summary, this article reviews the current research that enhances our understanding of the application of new botulinum neurotoxins in the context of common conditions and suggests new avenues for developing more efficient molecules.

The effectiveness of ultrasound-guided injection of BTX-A in the management of sialorrhea in neurogenic dysphagia patients

Objective

To evaluate the effectiveness of ultrasound-guided injection of botulinum toxin type A (BTX-A) in treating sialorrhea.

Methods

We recruited 32 sialorrhea subjects and they received an ultrasound-guided injection of BTX-A. The extent of salivation was evaluated according to the Visual Analog Scale (VAS), Drooling Severity and Frequency Scale (DSFS), and Saliva Flow Rate (SFR). Laryngeal secretions were evaluated based on Fiberoptic Endoscopic Evaluation of Swallowing (FEES) rated according to the Murray Secretion Scale (MSS). We assessed the extent of salivation and laryngeal secretions before injection and at 1, 2, and 4 weeks after injection.

Results

The scores for the VAS, DSFS-S, DSFS-F, and DSFS-T decreased significantly at 1, 2, and 4 weeks after injection compared with before injection (p < .05). Based on VAS, the efficacy was substantially higher at 2 and 4 weeks after injection than at 1 week after injection (p < .05). According to DSFS-S and DSFS-T, the efficacy was significantly higher at 4 weeks than at 1 week after injection (p < .05). The SFR and MSS scores at 1 and 2 weeks after injection were superior to those before injection (p < .05). Meanwhile, the SFR score 2 weeks after injection was superior to that 1 week after injection (p < .05).

Conclusion

The ultrasound-guided injection of BTX-A can effectively reduce saliva secretion in patients with neurogenic dysphagia. Furthermore, it has the advantages of early onset time and lasting curative effects, which indicates that clinical promotion and application of this technique are justified.

Level of Evidence

Level 3.

Guidelines for the Use of Botulinum Toxin in Otolaryngology From the Korean Society of Laryngology, Phoniatrics and Logopedics Guideline Task Force

The Korean Society of Laryngology, Phoniatrics and Logopedics created a task force to establish clinical practice guidelines for the use of botulinum toxin (BT) in otolaryngology. We selected 10 disease categories: spasmodic dysphonia, essential vocal tremor, vocal fold granuloma, bilateral vocal fold paralysis, Frey's syndrome, sialocele, sialorrhea, cricopharyngeal dysfunction, chronic sialadenitis, and first bite syndrome. To retrieve all relevant papers, we searched the CORE databases with predefined search strategies, including Medline (PubMed), Embase, the Cochrane Library, and KoreaMed. The committee reported 13 final recommendations with detailed evidence profiles. The guidelines are primarily aimed at all clinicians applying BT to the head and neck area. In addition, the guidelines aim to promote an improved understanding of the safe and effective use of BT by policymakers and counselors, as well as in patients scheduled to receive BT injections.

Safety considerations for treating the parotid and submandibular glands with neuromodulators for facial slimming

BACKGROUND

Neuromodulators have predominantly been used for the treatment of upper facial lines, but their use has expanded to include lower face and neck treatments. However, the injection sites for these treatments are based on skin surface landmarks, which may pose risks to nearby structures and result in undesired outcomes.

OBJECTIVE

To investigate the spatial relationship between the FDA-approved skin surface landmarks for neuromodulator injections in the parotid and submandibular glands and the topographical anatomy of critical facial structures such as the facial artery, facial vein, external carotid artery, and retromandibular vein.

MATERIALS AND METHODS

A cross-sectional retrospective analysis was conducted on contrast-enhanced cranial CT scans. The scans were analyzed for the morphology and location of the parotid and submandibular glands. Measurements were taken for gland volume, craniocaudal extent, anterior-posterior extent, and distances between the skin surface and gland capsule or nearby structures such as arteries.

RESULTS

The study sample consisted of 53 subjects, including 7 males and 46 females, with a mean age of 36.91 years and a mean BMI of 23.28 kg/m2 . The mean volume of the parotid gland was 31.9 ± 3.0 cc in males and 28.5 ± 3.6 cc in females with p < 0.001, while the mean volume of the submandibular gland was 18.2 ± 2.0 cc in males and 14.5 ± 3.4 cc in females with p < 0.001. The mean distances between skin surface and the gland capsule were 5.98 ± 2.2 and 8.84 ± 4.0 mm for the parotid and submandibular gland, respectively. This distance increased with higher age and higher BMI values in a statistically significant manner with p < 0.001.

CONCLUSION

The distances between FDA-approved skin surface landmarks and the parotid and submandibular glands varied significantly depending on gender, age, and BMI. Optimal injection depth and location for neuromodulator treatments cannot be generalized based on these landmarks alone, emphasizing the need for real-time ultrasound imaging guidance.

Mechanism and clinical use of botulinum neurotoxin in head and facial region

PURPOSE

Botulinum neurotoxin (BoNT) is a biological toxin produced by Clostridium botulinum. BoNT is a potent toxin extensively used in therapeutic interventions. This review provides an updated overview of the mechanisms of action and clinical applications of BoNT in head and facial region.

STUDY SELECTION

MEDLINE/PubMed searches were conducted using the terms "botulinum neurotoxin" and "dentistry" along with a combination of other related terms. In addition, studies were manually selected from reference lists of the selected articles.

RESULTS

The Food and Drug Administration in the United States initially approved BoNT to treat strabismus, blepharospasm, and hemifacial spasms. The use of BoNT in dermatology and cosmetics has been widely established and has created a revolution in these fields. Over the years, its applications in various medical specialties have expanded widely. Owing to its safety, efficacy, and long duration of action, it is well-accepted by patients. BoNT/A and BoNT/B are widely used in clinical practice. Several off-label uses of BoNT in the dental fraternity have yielded promising results. We have elaborated on the speculated mechanism of action, dosage, effective sites of injection, and adverse effects of each therapeutic application. The various clinical indications for BoNT include bruxism, myofascial pain, temporomandibular joint dislocation, hemifacial pain, orofacial dystonia, facial paralysis, chronic migraine, and trigeminal neuralgia.

CONCLUSIONS

BoNT is a safe treatment that can be used effectively, provided that the clinician has adequate knowledge regarding the mechanism, injection techniques, and local and systemic side effects and that it is administered cautiously and purposefully.

The effectiveness and safety of botulinum toxin injections for the treatment of sialorrhea with Parkinson's disease: a systematic review and meta-analysis

BACKGROUND

Botulinum toxin (BoNT) injection is an important adjunctive method to treat sialorrhea. The purpose of this systematic review was to analyze the effect and safety of BoNT injections in the intervention of sialorrhea with Parkinson's disease (PD).

METHODS

We searched PubMed, Web Of Science (WOS), Scopus, Cochrane CENTRAL, and Embase from inception until April 2022. Randomized controlled trials or randomized crossover trials comparing BoNT with placebo in sialorrhea with PD were eligible. PRISMA guidelines were used to carry out the meta-analysis. The Drooling Severity Frequency Scale (DSFS) score and the number of adverse events (AEs) were the primary and secondary outcomes, respectively. Standardized mean differences (SMDs) and risk differences (RDs) are used to express continuous and categorical outcomes, respectively. Heterogeneity among these studies was evaluated using I2 tests. We used the GRADE tool to assess the certainty of evidence (COE).

RESULTS

Eight articles involving 259 patients compared BoNT injections with a placebo for PD with sialorrhea. This meta-analysis showed a significant reduction in DSFS scores between BoNT injections and placebo (SMD=-0.98; 95% CI, -1.27 to 0.70, p<0.001; COE: high). This meta-analysis showed a significant difference in AEs between BoNT injections and placebo (RD=0.15; 95% CI, 0.05 to 0.24, p=0.002; COE: low).

CONCLUSIONS

The pooled results suggest that BoNT injections have some effect on DSFS scores with sialorrhea caused by PD. There are also mild adverse events, which generally recover within a week or so. The results indicate that BoNT injection is one of the treatments for sialorrhea caused by PD, but we need to pay attention to adverse events. In addition, the follow-up time was extended to observe oral hygiene, ulceration or dental caries, and digestive function.

TRIAL REGISTRATION

Our review protocol was registered on PROSPERO (42021288334).

Recommendations for a paradigm shift in approach to increase the recognition and treatment of sialorrhea in Parkinson's disease

Sialorrhea, or drooling, is defined as excessive saliva accumulation and unwanted loss of saliva from the mouth or over the tongue and into the pharynx. It constitutes one of the most frequent and bothersome complaints of patients with Parkinson's disease (PD), affecting up to 84% of them. Sialorrhea is a distressing and challenging condition that may result in social isolation, embarrassment, depression, skin infections, poor oral health, and aspiration pneumonia. To better understand the burden of sialorrhea on patients with PD, Parkinson's Europe carried out a worldwide patient survey which showed that sialorrhea remains an underrecognized and undertreated issue in patients with PD. This is especially problematic because effective therapeutic options are available. This article presents the results of the Parkinson's Europe Sialorrhea Survey, which were considered by a multidisciplinary panel of experts to provide recommendations for improving the awareness, diagnosis, management, and treatment of sialorrhea in patients with PD. A shift in the treatment paradigm for sialorrhea in patients with PD is emerging. It is essential to better educate patients, family members, caregivers, and healthcare professionals about sialorrhea; to engage all those involved to actively discuss sialorrhea and measure its impact on quality of life; and to recognize the role of botulinum toxin and speech and language therapy as first-line therapies.

Botulinum toxin in the management of parkinsonian disorders

Many studies have shown that botulinum toxin (BoNT) can be an option to treat motor and non-motor symptoms in Parkinson's disease (PD) and parkinsonian syndromes. The advantages of BoNT compared to oral medications include localized action and low incidence of systemic side effects, which is important in treating neurodegenerative disease. Motor symptoms that can be treated with BoNT include blepharospasm, apraxia of eyelid opening, tremor, cervical dystonia and limb dystonia. Other indications with less evidence include camptocormia, freezing of gait and dyskinesia. Non-motor symptoms that may improve with BoNT include sialorrhea, pain, overreactive bladder, dysphagia and constipation. However, the current evidence for use of BoNT in parkinsonism is mostly based on open-label studies and there are few randomized, controlled trials. BoNT can be a valuable tool to treat certain symptoms of PD and parkinsonian syndromes to improve the patient's quality of life. However, many of the uses are not supported by high quality studies and further studies are needed to provide further evidence of efficacy, define the optimal injection protocols such as doses and muscle selection.

Second to none: rationale, timing, and clinical management of clozapine use in schizophrenia

Despite its enduring relevance as the single most effective and important evidence-based treatment for schizophrenia, underutilization of clozapine remains considerable. To a substantial degree, this is attributable to a reluctance of psychiatrists to offer clozapine due to its relatively large side-effect burden and the complexity of its use. This underscores the necessity for continued education regarding both the vital nature and the intricacies of clozapine treatment. This narrative review summarizes all clinically relevant areas of evidence, which support clozapine's wide-ranging superior efficacy - for treatment-resistant schizophrenia (TRS) and beyond - and make its safe use eminently feasible. Converging evidence indicates that TRS constitutes a distinct albeit heterogeneous subgroup of schizophrenias primarily responsive to clozapine. Most importantly, the predominantly early onset of treatment resistance and the considerable decline in response rates associated with its delayed initiation make clozapine an essential treatment option throughout the course of illness, beginning with the first psychotic episode. To maximize patients' benefits, systematic early recognition efforts based on stringent use of TRS criteria, a timely offer of clozapine, thorough side-effect screening and management as well as consistent use of therapeutic drug monitoring and established augmentation strategies for suboptimal responders are crucial. To minimize permanent all-cause discontinuation, re-challenges after neutropenia or myocarditis should be considered. Owing to clozapine's unique efficacy, comorbid conditions including substance use and most somatic disorders should not dissuade but rather encourage clinicians to consider clozapine. Moreover, treatment decisions need to be informed by the late onset of clozapine's full effects, which for reduced suicidality and mortality rates may not even be readily apparent. Overall, the singular extent of its efficacy combined with the high level of patient satisfaction continues to distinguish clozapine from all other available antipsychotics.

BoNT clinical trial update: Sialorrhea

Sialorrhea is the excessive accumulation of saliva, a prevalent symptom among a number of neurologic conditions in both pediatric and adult patients. Over the years, the management of sialorrhea has evolved and included a variety of interventions, ranging from nonpharmacologic, pharmacologic, and surgical treatment options. The most common option for treatment has been the use of botulinum toxin injections in the management of sialorrhea. While there have been several clinical trials to assess the efficacy of botulinum toxin in the treatment of sialorrhea, the largest randomized control trials to date have been with incobotulinumtoxin (2019) and rimabotulinumtoxin (2020) which show consistent reduction in salivary flow rate and improvement in clinical outcomes with comparable duration of treatment effectiveness. In this update, we review the evolution of treatment and injection methods for sialorrhea among many neurologic diseases. We discuss the challenges in evaluating and measuring efficacy in clinical trials for sialorrhea and compare the contemporary botulinum toxin clinical trials in the treatment of sialorrhea.

Botulinum Toxin, a Drug with Potential Interest for Dentists—An Introduction

The review is an introduction to medical, non-cosmetic treatments with botulinum neurotoxin (BoNT) in the orofacial region. It focuses on the current most common, best-documented and safest indications of interest for dentists in terms of dystonia and sialorrhea. These conditions are recommended to start with and suitable to gain better skill and experience with BoNT. The introduction also stresses the importance of correct diagnostics based on interdisciplinary cooperation, precise targeting of the injections, measurements of treatment effect, and control of the oral health with regard to side effects.

Alteration of tight junctions during botulinum toxin type A-inhibited salivary secretion

OBJECTIVES

Tight junctions (TJs) are involved in the regulation of salivary secretion via paracellular pathway. Botulinum toxin type A (BTXA) is widely used for the treatment of hypersecretion diseases such as sialorrhea. This study aimed to investigate the role of TJs in BTXA-inhibited secretion of the submandibular gland (SMG).

MATERIALS AND METHODS

BTXA was injected into the SMGs of rats, and the same amount of saline was injected as a control. Western blot, real-time PCR and immunofluorescence staining were used to detect the expression and distribution of TJ proteins. Paracellular permeability was evaluated using the transepithelial electrical resistance (TER) measurements and fluorescent tracer detection in BTXA-stimulated SMG-C6 cells.

RESULTS

BTXA injection into the SMGs of rats led to increased expression of claudin (Cldn) -1 and Cldn3. Immunofluorescence staining showed no significant changes in the distribution of TJ proteins. In vitro, BTXA increased the TER values and significantly reduced the permeability of fluorescent tracer, suggesting that BTXA decreased the paracellular permeability. The expression levels of Cldn1, Cldn3 and Cldn4 were upregulated after BTXA treatment.

CONCLUSION

The expression of TJ proteins changed in both animal models and SMG-C6 cells after BTXA treatment, which may contribute to the inhibition of salivary secretion.

Pediatric Salivary Gland Disease

Salivary gland disease in the pediatric population is rare, yet it encompasses a wide spectrum of disease. It is estimated that 4.3% of salivary gland disease occurs in the pediatric population, with most classified as nonneoplastic. Further extrapolation reveals that 5% of salivary gland neoplastic diseases occur in patients younger than 20 years. Moreover, salivary gland tumors represent 1% of all head and neck tumors across all ages. Regardless, clinicians across all fields should be familiar with the workup of various pediatric salivary gland diseases and appropriate referral to a pediatric otolaryngologist.

Safety of High-Dose Botulinum Toxin Injections for Parotid and Submandibular Gland Radioprotection

Botulinum Toxin injections into salivary glands (SG) up to a total dose of 100 units IncobotulinumtoxinA (IncoA) represent the treatment of choice for sialorrhea. However, BTX might also protect SG against sialotoxic radioligand cancer therapies. The radioligand Actinium-225-PSMA effectively targets Prostate Cancer (PCa) metastases but inevitably destroys SG due to unintended gland uptake. A preliminary case series with regular-dose IncoA failed to reduce SG PSMA-radioligand uptake. We therefore increased IncoA dosage in combination with transdermal scopolamine until a clinically relevant SG PSMA-radioligand uptake reduction was achieved. Ten consecutive men with metastasized PCa refractory to all other cancer therapies received gradually increasing IncoA dosages as part of a compassionate use PSMA-radioligand-therapy trial. The parotid gland received six and the submandibular gland three injection points under ultrasound control, up to a maximum of 30 units IncoA per injection point. A maximum total dose of 250 units IncoA was applied with up to 170 units per parotid and 80 units per submandibular gland. Treatment was well tolerated and all side-effects were non-serious. The most frequent side-effect was dry mouth of mild severity. No dysphagia, facial weakness, chewing difficulties or systemic side-effects were observed. SG injections with IncoA up to a total dose of 250 units are safe when distributed among several injection-points under ultrasound control by an experienced physician. These preliminary findings lay the basis for future trials including BTX as major component for SG protection in established as well as newly emerging radioligand cancer therapies.

A critical review of incobotulinumtoxinA in the treatment of chronic sialorrhea in pediatric patients

INTRODUCTION

Sialorrhea, also known as hypersalivation, ptyalis, or drooling, results in physical and psychosocial complications that may have a significant negative impact on quality of life for both the patient and their caregiver. The goal of pharmacological treatment is to reduce excessive salivary flow, while maintaining a moist and healthy oral cavity; until recently, however, few of the agents used to treat chronic sialorrhea have been approved in pediatric patients.

AREAS COVERED

This article summarizes early evidence for the use of botulinum neurotoxin A formulations in the treatment of children/adolescents with chronic sialorrhea, and findings of the recently completed phase III trial of incobotulinumtoxinA in this indication. Alternative therapies are also briefly discussed.

EXPERT OPINION

IncobotulinumtoxinA is the first botulinum neurotoxin A to be approved for the treatment of chronic sialorrhea in children and adults, following the results of phase III trials that demonstrate the efficacy and safety of the drug in these patients. The authors expect that the positive findings will result in updates to clinical guidelines for the treatment of children with chronic sialorrhea.

ABBREVIATIONS

AE, adverse event; AESI, adverse event of special interest; BoNT/A, botulinum neurotoxin A; CI, confidence interval; CP, cerebral palsy; DIS, drooling impact scale; DQ, drooling quotient; DSFS, Drooling Severity and Frequency Scale; GICS, Global Impression of Change Scale; LS, least squares; mTDS, modified Teacher's drooling scale; NR, not reported; PD, Parkinson's disease; SAE, serious adverse event; SE, standard error; SIAXI, Sialorrhea in Adults Xeomin Investigation; SIPEXI, Sialorrhea Pediatric Xeomin Investigation; SNAP-25, synaptosomal associated protein-25; TBI, traumatic brain injury; TDS, Teacher Drooling Scale; USA, United States of America; uSFR, unstimulated Salivary Flow Rate; VAS, visual analog scale.

Botulinum Toxin Services for Neurorehabiliation: Recommendations for Challenges and Opportunities during the COVID-19 Pandemic

The COVID-19 pandemic severely impacted the function of medical facilities and rehabilitation services worldwide, including toxin services delivering Botulinum toxin treatments for neuromuscular conditions such as spasticity, dystonia, and sialorrhea. The aim of this paper is to understand how toxin services have dealt with the situation and what strategies have been adopted to continue services. The recommendations are based on a virtual round table held with toxin services experts from different European countries who shared their experiences and discussed the best practices. The challenges for toxin services were reviewed based on the experts' experiences and on relevant literature from 2020 and 2021. A set of recommendations and best practices were compiled, focusing firstly on guidance for clinical practice, including assessing patients' health and risk status and the urgency of their treatment. Secondly, it was discussed how patients on botulinum toxin therapy can be cared for and supported during the pandemic, and how modern technology and tele-medicine platforms can be generally used to optimize effectiveness and safety of toxin treatments. The technological advances prompted by the COVID-19 crisis can result in better and more modern patient care in the future.

Oral health effects of botulinum toxin treatment for drooling: a systematic review

Background

Drooling is a major morbidity in several neurological diseases. Intraglandular botulinum neurotoxin (BoNT) injections have been used to manage this condition. However, by decreasing salivary flow, BoNT injections may result in an increased risk of caries and other oral adverse effects. In this study, we aimed to assess whether, in patients with drooling, intraglandular BoNT injections are associated with increased dental caries development, modifications on salivary composition (oral pH, buffering capacity and osmolality) and cariogenic bacterial load.

Material and Methods

We performed a systematic review, searching PubMed, CENTRAL, Web of Science, and Scopus for all experimental and observational studies reporting on adverse effects of intraglandular BoNT injections in patients with drooling. Primary study selection, quality assessment, and data extraction were independently performed by two researchers. No studies were excluded based on their language, publication status or date of publication. Studies’ quality was based on revised Cochrane Risk of Bias tools. Meta-analysis was not performed.

Results

We retrieved 1025 studies, of which 5 were included. Two studies were two randomized controlled trials and three quasi-experimental studies. None of the included studies found BoNT injections to be associated with dental caries development or with significant reductions in oral pH. One of the included primary studies even observed an increase in salivary buffer capacity. One study found an increase in Lactobacilli counts. As for the risk of bias, two studies were classified as having a critical risk, two as high risk and one as having some concerns.

Conclusions

Currently, there is no evidence that, in patients with drooling, BoNT injections associate with increased risk of dental caries or disturbances in oral pH or salivary buffering capacity. However, the included primary studies had important limitations and differences in their methodologies.

Key words:Neurological diseases, drooling, sialorrhea, botulinum toxin, oral health, caries, saliva.

Use of Botulinum Neurotoxin in Parkinson's Disease: A Critical Appraisal

For well over 30 years, the botulinum neurotoxin (BoNT) has been used for a large number of indications, some of which however have not been licensed. Admittedly, approval varies in many countries and this permits a large spectrum for evaluation. Thus, BoNT is used for patients with Parkinson’s disease (PD) and other Parkinson’s syndromes (PS) in varying degrees of frequency. We have to distinguish between (1) indications that are either approved or (2) those not approved, (3) indications that might be a result of PS and (4) finally those which appear independent of PS. The most important indication for BoNT in PS patients is probably sialorrhea, for which approval has been granted in the majority of countries. Cervical dystonia is a frequent symptom in PS, with anterocollis as a specific entity. A further indication is blepharospasm in the different forms, especially the inhibition of eyelid opening in atypical PS. The use of BoNT in cases of camptocormia, the Pisa syndrome and neck rigidity is still a matter of debate. In dystonia of the extremities BoNT can be recommended, especially in dystonia of the feet. One well-known indication, for which however sufficient data are still lacking, involves treating tremor with BoNT. As to autonomic symptoms: Focal hyperhidrosis and detrusor hyperactivity can be mentioned, in this last case BoNT has already been approved. A number of further but rare indications such as freezing-of-gait, dyskinesia, and dysphagia will be discussed and evaluated.

Accuracy of non-guided versus ultrasound-guided injections in cervical muscles: a cadaver study

INTRODUCTION

The col-cap concept encouraged neurologists to inject a large group of muscles in the treatment of cervical dystonia. This includes deep muscles such as the obliquus capitis inferior or the semispinalis capitis, and muscles close to vascular or neurological structures such as scalene muscles. Our aim was to determine the accuracy of injections in cervical muscles using ultrasonography (US) or palpation of anatomical landmarks.

METHODS

A mix of paint, gelatin and iodized contrast agent was injected in nine pairs of cervical muscles of human cadavers, according to two injection techniques: US-guided and non-guided. The dye was localized on 1 cm-thick, frozen slices.

RESULTS

A total of 102 muscles was injected in the US-guided group (n = 8). The global accuracy was 88.2%. The lowest accuracy was in the OCI (41.7%); trying to avoid the vertebral artery, injections were too medial. A total of 54 muscles was injected in the non-guided group (n = 3). The global accuracy was 48.0%; moreover, some dye was found in four blood vessels. The embalming process produced texture changes, making difficult the palpation of bony landmarks.

CONCLUSIONS

Our results indicate that US-guided injections are more accurate than non-guided injections in most cervical muscles.

Pharmacotherapy for reducing saliva and droplet production in airborne procedures may help to decrease the COVID-19 transmission: A hypothesis

The pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has affected health care service practices worldwide. Therefore, a global reaction to prepare health care systems is mandatory. Preventing the transmission of this virus during medical and dental procedures producing airborne particles and droplets, could be considered as one of the main venues in prevention of Coronavirus disease 2019 (COVID-19) transmission in health care facilities. To the best of our knowledge, no intervention has been approved for this purpose, so the major suggestion in this regard is using personal preventive equipment (PPE) and similar measures as well as other sanitizing practices. Since we do not know how long we should face this universal issue, using antecedent pharmacotherapies for reducing oral-respiratory secretions to combat this virus might play a role in this regard. Given that currently there is no definitive cure for COVID-19, so we hypothesize that, considering drug solutions to reduce saliva and droplet production may be helpful in controlling Coronavirus spread during aerosol and respiratory droplet producing procedures.