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.