BOTOX-A injection of salivary glands for drooling.

[BACKGROUND AND PURPOSE] Drooling is a challenging entity to manage. Botulinum toxin A (BOTOX-A) infiltration of salivary glands is a promising alternative to surgical treatment. This study aims to assess the outcome of BOTOX-A salivary glands infiltration in children with drooling.

[METHODS] Patients treated between January 2012 and March 2015 were enrolled. BOTOX-A was injected in the parotid and submandibular glands under ultrasound control and general inhalational anesthesia. The outcome was evaluated through the DSFS: Drooling Severity (1-best to 5-worst) and Frequency (1 to 4) Scale, that was applied before treatment, and 1-, 3-, and 6-month after injection. The inclusion criteria were a DSS ≥4 and/or DFS ≥3. Statistical significance was set at 5%.

[RESULTS] There were 17 patients aged 12.1±5.1 [4-19]years, all of them with neurologic impairment. After the first injection, 13 (76.5%) patients had reduction of the severity (S) and 12 (70.6%) of the frequency (F) scale; in 6 (35.5%) patients drooling resolved completely. Pre-treatment S+F score was 8.59±0.71 [7-9]; it decreased significantly to 4.65±2.32 (p=0.001) at 1-month post-injection evaluation. At 3-month and 6-month the scores were also significantly lower than the pre-treatment one (4.00±1.96, p=0.002; 5.36±2.20, p=0.005; respectively), but there was a significant increase between the 3-month and 6-month evaluations (p=0.01). With a follow-up of 20.1±9.2 [4-38] months, 4 out of the 13 successful injections needed a second one after 7.5±3.1 [3-10] months. The patient with the longest time not requiring re-injection had 28months of follow-up. One (6%) patient presented mild dysphagia that regressed spontaneously. All but two (88%) parents/caregivers would repeat the treatment.

[CONCLUSIONS] BOTOX-A seems to be an effective minimal invasive treatment for drooling with few complications. After 6months the need for re-injection becomes substantial but it may not be necessary for several months. Further studies are needed to establish the most effective dosage and frequency of injections.

[LEVEL OF EVIDENCE] IV.