Effect of Botulinum Toxin Type A on Morphology of Salivary Glands in Patients with Cerebral Palsy

Objective To investigate the effect of botulinum toxin type A (BTXA) on drooling and the morphologic change of the salivary gland in patients with cerebral palsy. Method Eight cerebral palsy patients suffering from severe drooling participated in this study. BTXA was injected into both submandibular and parotid glands under intravenous sedation and with ultrasound guidance (1 unit/gland/kg: maximum 100 units) in an outpatient or inpatient procedure. The severity of drooling was measured before injection and 3 weeks after injection using the Teacher Drooling Scale, the Drooling Score-severity, frequency and the Visual Analog Scale. To investigate the morphologic change of the salivary glands, the size of salivary glands were measured before injection and 3 weeks after injection using computed tomography of the neck. The measurement values were analyzed by Wilcoxon signed rank test. Results Statistically significant improvements were shown in all three parameters for assessing the severity of drooling after BTXA injections (p<0.05). Size of the salivary glands were significantly decreased at 3 weeks after BTXA injection (p<0.05). Conclusion Salivary gland injection with BTXA could be a useful treatment method to reduce drooling in patients with cerebral palsy and decreased size of salivary glands may partially explain the mechanism.