Parotid and submandibular botulinum toxin A injections for sialorrhoea in children with cerebral palsy

Abstract

The aim of this study was to determine whether botulinum toxin A (BTX‐A) injected into the parotid and submandibular salivary glands of children aged 6 to 16 years with cerebral palsy (CP) and relative sialorrhoea significantly decreases their drooling and improves their quality of life. Twenty children (10 males, 10 females; mean age 10y 1mo [SD 3y 8mo]; range 6y 1mo‐16y 7mo) with CP, identified as having significant daily drooling (scoring at least 6 on drooling frequency/severity scales) were recruited. BTX‐A (2U/kg; maximum 70U) was injected under sedation, using ultrasound guidance (1.4U/kg and 0.6U/kg divided between parotid and submandibular glands respectively). Nineteen children completed the study: 15 with spastic quadriplegia (Gross Motor Function Classification System [GMFCS] Level V); one with dystonia (GMFCS Level V); one with hemiplegia (GMFCS Level II); and two with a mixed pattern of CP (GMFCS Levels III and V). Drooling was assessed by five methods at baseline, and 4 and 12 weeks after injection. Qualitative assessment of drooling frequency and severity scores showed statistically significant reductions at 4 weeks (p≤0.001) and 12 weeks (p=0.006). Qualitative assessment of quality of life scores (rated by parents and teachers separately) also significantly improved (p≤0.001 and P=0.023 respectively). Quantitative assessments showed that the number of bibs/scarves changed per day was significantly reduced at 4 weeks (p≤0.001). There was no side effect from the injections themselves; 89% of parents and children wished for further intrasalivary BTX‐A injections in the future. We conclude that percutaneous intrasalivary BTX‐A injections into the parotid and submandibular salivary glands can reduce drooling in children with CP and relative sialorrhoea, leading to an improvement in their quality of life.

Developmental assessment of preterm infants at 2 years: validity of parent reports

“…Some have been case series, 10,11 but the majority were individual cohort studies involving from three to 22 participants. 10,[12][13][14][15][16][17] All have been unblinded, open-label studies. The parotid glands were injected in three studies, [12][13][14] the submandibular glands alone in three, 10,11,17 and both sets of glands in two.…”

“…The parotid glands were injected in three studies, [12][13][14] the submandibular glands alone in three, 10,11,17 and both sets of glands in two. 16,18 In a dose escalation study, Suskind and Tilton 19 compared injections into the submandibular glands alone with injections into the submandibular and parotid glands, and found there were more responders when both sets of glands were injected. No conclusion was drawn as to the ideal dose.…”

“…Some recent studies calculated the dose by bodyweight from 1unit/kg 10 to 2units/kg. 16 The number of submandibular injection sites ranged from one 16,19 to at least three; 17 the number of parotid injection sites was either one 12,14 or two. 13,16,19 The injected volume was not always reported but tended to range from 1ml/gland downwards.…”

“…16 The number of submandibular injection sites ranged from one 16,19 to at least three; 17 the number of parotid injection sites was either one 12,14 or two. 13,16,19 The injected volume was not always reported but tended to range from 1ml/gland downwards. Jongerius et al 8 published an in vitro study that suggested that BoNT-A for each gland should be diluted in a volume of 1 to 1.5ml saline to achieve adequate spreading and diminish the risk of diffusion into surrounding structures.…”

“…The only study with sufficient numbers of participants in which both the submandibular and parotid glands were injected showed a 10% non-response rate using both objective and subjective measures. 16 Most of the reviewed studies reported effects lasting from 8 to 16 weeks. [12][13][14]16,17 Only one study followed up children for 6 months, but found that any statistically significant improvements had disappeared by 3 months, and that most children had returned to baseline by this time.…”