Botulinum Toxin A in the Management of Pediatric Sialorrhea: A Systematic Review

Management of paediatric sialorrhea

PURPOSE OF REVIEW

To summarize current understanding of and recent literature on the management of sialorrhea in children.

RECENT FINDINGS

Sialorrhea is a symptom of oropharyngeal dysphagia and reduced clearance. Sialorrhea can be anterior, with forward overflow of saliva, causing skin rash, social embarrassment and spillage on communication devices; or posterior, where there is pharyngeal pooling of saliva, which may cause aspiration.Assessment of sialorrhea involves a clinical evaluation, focusing on the individual's age, development, underlying medical condition and whether the sialorrhea is anterior, posterior or both. Craniomaxillofacial structure, posture, airway patency, neuromotor control, level of social awareness, motivation and caregiver concerns are assessed. To manage sialorrhea, integration of multiple strategies is usually needed. There is good evidence for behavioral intervention, oral appliances, anticholinergic medications, botulinum toxin injection and surgery. The role of various options of surgery in providing a longer lasting effect is supported. Adjunctive airway and craniomaxillofacial surgery may be indicated.

SUMMARY

Sialorrhea is a modifiable condition with multifactorial causes requiring multimodal therapy by an inter-disciplinary team. There is increasing evidence on the role of saliva surgery in improving the quality of life for the person with sialorrhea and their caregivers.

A Six-Year Examination of the Influence of Surgical Technique and Intraoperative Intraglandular Clostridium Botulinum Toxin Application in Salivary Gland Tumor Operations

Introduction: Salivary gland tumor operations are associated with complications including facial nerve dysfunction (FND) and salivary fistula. The objective of this study was to investigate the effect of extracapsular dissection (ECD) and the application of Clostridium botulinum toxin (CBT) in contrast to partial and lateral parotidectomy on complications. Methods: All salivary gland tumor operations performed within the last 6 years were retrospectively examined. Data were collected from electronic patient files from our otorhinolaryngology clinic. Total parotidectomies and submandibulectomies were not included in the analysis of CBT application. Results: In total, 418 cases were examined, including 84 (20%) malignant tumors. In total, 18 patients underwent ECD, 93 partial parotidectomy, 199 lateral parotidectomy, 76 total parotidectomy, and 32 submandibulectomy. The most common complication was transient FND (49%; n = 205; data available for 415 patients), which was measured at four days. Additional complications included salivary fistula (n = 56), infection (n = 49), bleeding or hematoma (n = 21). Preoperative facial nerve paralysis (p < 0.0001), pain (p < 0.0001), and a history of squamous cell skin carcinoma (SCC) (p < 0.001) were predictive of malignancy. The application of CBT did not reduce the risk of salivary fistula (p-value: 0.0182) and was associated with a higher combined complication rate (p-value: 0.0199). ECD was not associated with a lower likelihood for FND (p = 0.350). Conclusions: Preoperative pain, facial paralysis, or a history of SCC are predictors of malignancy. Use of CBT was not associated with a reduced risk of salivary fistula, but rather a higher complication rate.

Staggered botulinum toxin-a injections into parotid and submandibular glands prior to four-duct ligation for pediatric sialorrhea

OBJECTIVES

This study aimed to assess the effectiveness of four-duct ligation following Botulinum toxin-A injections into the parotid and submandibular glands in pediatric patients with sialorrhea resistant to nonsurgical treatments. Prior research has individually explored either surgical or Botulinum toxin interventions; however, the safety and efficacy of the combined approach to these treatments have yet to be documented.

METHODS

Patients were assessed before surgery and 6, 12, and 24 months post-operatively. Evaluations involved interviews with parents and caregivers, conducted face-to-face or by telephone, using the Drooling Severity and Frequency Scales. Additionally, metrics such as the daily count of bib changes and the hourly frequency of saliva wiping were recorded. Quality-of-life assessments were performed before and after the surgical procedures. All complications associated with the interventions were carefully recorded.

RESULTS

The study group consisted of 25 participants, with a median age of 6 years (range 2-17 years). Each participant was diagnosed with a neurological, metabolic, or genetic disorder. Evaluations were conducted periodically, culminating in a final follow-up at 24 months. The treatment demonstrated a 100% success rate at six months post-operation (25/25 patients), which slightly decreased to 96% at the 12-month mark (24/25 patients) and further to 84% by the 24-month follow-up (21/25 patients). Major complications were not observed. However, minor complications were reported in six patients (24%): three exhibited temporary facial swelling (12%), two encountered minor bleeding (8%), and one experienced excessive dryness (4%).

CONCLUSIONS

The combination of Botulinum toxin-A injection 3 weeks prior to the four-duct ligation procedure demonstrated high success rates and substantially reduced the incidence of infectious and cosmetic complications. Consequently, this staggered approach to combination treatment is recommended for managing pediatric sialorrhea cases that are resistant to non-surgical interventions.

Negative effects on oral motor function after submandibular and parotid botulinum neurotoxin A injections for drooling in children with developmental disabilities

AIM

To evaluate negative effects on oral motor function after concurrent submandibular and parotid (four-gland) botulinum neurotoxin A (BoNT-A) injections as a treatment for paediatric drooling.

METHOD

This was a retrospective cohort study of 125 children (median age 7 years 7 months [interquartile range 4 years 5 months]) with developmental disabilities, including cerebral palsy, treated with four-gland injections. Most children (90.4%) were previously exposed to submandibular injections. Frequency, severity, and duration of negative effects on oral motor function (i.e. saliva swallowing, eating, drinking, articulation) were evaluated and compared to a reference cohort treated with submandibular injections.

RESULTS

Negative effects on oral motor function were reported in 45 children (36.0%), predominantly manifesting as eating-related problems (64.4%). Most negative effects (62.2%) were classified as mild and resolved within 4-weeks post-injunction (53.3%). Compared to the reference cohort, frequency (36.0% vs 33.0%) and duration (53.3% vs 53.6% resolving within 4 weeks) of negative effects were comparable, although problems were more often moderately severe (33.3% vs 10.1%).

INTERPRETATION

While negative effects on oral motor function were relatively common after four-gland BoNT-A injections, most problems were mild and resolved promptly. No substantial differences to a reference cohort treated with submandibular injections were observed, although further research should establish the generalizability of these findings in a treatment-naive population. Nevertheless, when submandibular injections prove ineffective, clinicians can confidently consider four-gland injections.

Navigating the spectrum of pediatric sialorrhea management: A narrative review

OBJECTIVE

This review summarizes the approaches to pediatric sialorrhea management from least-to-most invasive: non-pharmacological management, anticholinergic medications, botulinum neurotoxin, non-invasive surgery, and invasive surgical intervention.

REVIEW METHODS

An electronic literature review identified English-language articles on sialorrhea management in pediatric patients. Publications between 1982 and 2022 were used, with a focus on articles published from 2012 to 2022. Additional augmentation of pharmacologic information was obtained from the latest editions of medical textbooks supplemented with official package inserts of investigated medications.

CONCLUSIONS

Sialorrhea is abnormal in patients greater than four years of age. Severe cases warrant intervention to improve patient quality of life and reduce caregiver burden. Management starts with conservative approaches. Viable candidates begin with non-pharmacological management options. Anticholinergic medications can decrease saliva production, but adverse side effects may outweigh benefits. Botulinum neurotoxin injection of the salivary glands decreases salivary flow rate; however, relief is transient and thus multiple treatments are required. Non-invasive sclerotherapy is an emerging treatment option showing promising results for sialorrhea. In contrast, surgical intervention is reserved as a last-resort treatment for patients with severe symptoms, due to its higher risk for adverse consequences.

IMPLICATIONS FOR PRACTICE

Physicians should be familiar with the different pediatric sialorrhea management options, including advantages and disadvantages, to adequately facilitate shared decision making with caretakers of pediatric patients who require treatment.

Understanding Clinical Effectiveness and Safety Implications of Botulinum Toxin in Children: A Narrative Review of the Literature

Since its first approval by the Food and Drug Administration in 1989 for strabismus, botulinum toxin indications of use have been widely expanded. Due to its anticholinergic properties, this toxin is currently approved in adult patients for the treatment of a wide range of neuromuscular, otolaryngologic, orthopedic, gastrointestinal, and urologic disorders. Approved pediatric indications of use include the treatment of blepharospasm associated with dystonia, strabismus, lower-limb spasticity, focal spasticity in patients with cerebral palsy, and neurogenic detrusor overactivity. Alongside these approved indications, botulinum toxin is extensively used off-label. Although several clinical studies have shown that botulinum toxin is effective and well-tolerated in children, uncertainties persist regarding its long-term effects on growth and appropriate dosing in this population. As such, further research is needed to better define the botulinum toxin risk-benefit profile and expand approved uses in pediatrics. This narrative review aimed to provide a broad overview of the evidence concerning the clinical effectiveness and safety of BoNT with respect to its principal authorized and non-authorized pediatric therapeutic indications, as well as to describe perspectives on its future use in children.

Salivary toxicity from PSMA-targeted radiopharmaceuticals: What we have learned and where we are going

Clinical trials of prostate-specific membrane antigen (PSMA) targeted radiopharmaceuticals have shown encouraging results. Some agents, like lutetium-177 [177Lu]Lu-PSMA-617 ([177Lu]Lu-PSMA-617), are already approved for late line treatment of metastatic castration-resistant prostate cancer (mCRPC). Projections are for continued growth of this treatment modality; [177Lu]Lu-PSMA-617 is being studied both in earlier stages of disease and in combination with other anti-cancer therapies. Further, the drug development pipeline is deep with variations of PSMA-targeting radionuclides, including higher energy alpha particles conjugated to PSMA-honing vectors. It is safe to assume that an increasing number of patients will be exposed to PSMA-targeted radiopharmaceuticals during the course of their cancer treatment. In this setting, it is important to better understand and mitigate the most commonly encountered toxicities. One particularly vexing side effect is xerostomia. In this review, we discuss the scope of the problem, inventories to better characterize and monitor this troublesome side effect, and approaches to preserve salivary function and effectively palliate symptoms. This article aims to serve as a useful reference for prescribers of PSMA-targeted radiopharmaceuticals, while also commenting on areas of missing data and opportunities for future research.

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.

Transient Worsening of Dysphagia and Dysarthria after Treatment with Botulinum Toxin in Patients with Acquired Brain Injury

Although botulinum toxin is widely considered an effective and safe treatment for a variety of neurological conditions (such as disabling spasticity), local or systemic adverse effects have often been reported. This study describes three cases of patients with severe acquired brain injury who were receiving speech therapy for recovering dysphagia and dysarthria but showed worsening of these symptoms after receiving BoNT treatment for motor spasticity. To increase clinicians' knowledge of these adverse effects, we present our cases and explore their significance to avoid major complications such as aspiration pneumonia.

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.