Posterior drooling in children with cerebral palsy and other neurodevelopmental disorders.

AIM: To evaluate the effect of botulinum neurotoxin A (BoNT-A) injections, submandibular gland excision (SMGE), and bilateral submandibular duct ligation (2DL) for the control of posterior drooling in children with neurological impairment. METHOD: In a retrospective cohort, children with neurological impairment (e.g. cerebral palsy) treated between 2000 and 2016 were identified. Mean age at time of surgery was 9 years (range 1-21y). The primary outcome was posterior drooling severity by a visual analogue scale (VAS; 0-10) at baseline, 8-weeks, and 32-weeks follow-up. The secondary outcome was lower respiratory tract infections during the follow-up period. RESULTS: Ninety-two patients (out of 475; 47 males, 45 females) were identified. They were undergoing three different treatments: BoNT-A (n=63), SMGE (n=16), and 2DL (n=13). A significant reduction in VAS over time was observed in the total group of 92 patients. After SMGE, VAS decreased significantly from 6.82 (SD 3.40) at baseline to 2.29 (SD 1.93) at 8 weeks, and 2.17 (SD 2.58) at 32 weeks (F[2.34]=11.618, p<0.001). There was no significant decrease after both BoNT-A and 2-DL. INTERPRETATION: Posterior drooling is an unfamiliar, potentially life-threatening condition that is treatable with medication, BoNT-A injections, or surgery. Although all treatments reduced signs and symptoms of posterior drooling, there is a greater effect after SMGE compared to BoNT-A and 2-DL. What this paper adds Submandibular gland excision has better results for posterior drooling than botulinum toxin A or submandibular duct ligation.

Repeated onabotulinum neurotoxin A injections for drooling in children with neurodisability.

AIM: To evaluate the effect of repeated onabotulinum neurotoxin A injections for the treatment of drooling in children with neurodisabilities. METHOD: This was a retrospective cohort study, in which the first, second, and third onabotulinum neurotoxin A injection were compared within children treated between 2000 and 2020. Primary outcomes included drooling quotient, visual analogue scale (VAS), and treatment success defined as ≥50% reduction in drooling quotient and/or VAS 8 weeks after treatment. Each outcome was obtained at baseline and 8 weeks posttreatment. RESULTS: Seventy-seven children were included (mean age at first injection: 8y 3mo, SD 3y 7mo, range 3-17y; 44 males, 33 females; 51.9% with cerebral palsy, 45.5% wheelchair-bound). The objective (drooling quotient) and subjective (VAS) effect after the second injection was lower compared to the first injection. The third injection showed less objective and significantly less subjective effect compared to the first injection. An overall success rate of 74.0%, 41.6%, and 45.8% were found for the first, second, and third injection respectively. INTERPRETATION: Although onabotulinum neurotoxin A remained effective throughout the entire treatment course, there is less effect of subsequent onabotulinum neurotoxin A injections compared to the first. Although there might be a loss of effect after repeated injections, there is continued improvement for most children. What this paper adds Repeated injections show a diminished treatment effect after the second injection. A continued improvement is seen in most patients.

Thickened saliva after effective management of drooling with botulinum toxin A.

AIM: The aim of this study was to evaluate the rheological properties of saliva after submandibular botulinum toxin type A (BoNT-A) injections. METHOD: We enrolled 15 children (11 males and six females; age range 3-17 y, mean age 9 y 10 mo) diagnosed with spastic (n=9) or dyskinetic (n=6) quadriplegic cerebral palsy (CP); Gross Motor Function Classification System level IV or V; and two children with intellectual disability (IQ<70) who experienced moderate to severe drooling. Salivary flow rate and drooling quotient were measured at baseline and at different times after BoNT-A injections up to 24 weeks. The mucin concentration of saliva was analysed before and after BoNT-A treatment. RESULTS: Both submandibular salivary flow rate (baseline 0.38 mL/min; 24 wks after injection 0.26 mL/min) and drooling quotient (baseline 42.5%; 24 wks 28.80%) were substantially reduced, with a concomitant increase in mucin concentration within 8 weeks after BoNT-A injection (from 0.612 to 1.830 U/mL). The parents of nine children observed thickened saliva. Swallowing and chewing were problematic in seven children. Two of these children needed treatment with mucolytics because of pooling of thickened saliva in the throat. INTERPRETATION: When making decisions about the use of BoNT-A, the risk of problems with masticatory and swallowing functions as a result of thickening of saliva after BoNT-A treatment should be taken into account.