A Clinical Study of Ultrasound-guided Botulinum Toxin A Into Salivary Gland for Sialorrhea After True Bulbar Palsy

"Ultrasound-guided injection of BoNT-A (specific dosage, e.g., 100 units) into target salivary glands ( parotid and submandibular glands) at baseline."

"Intervention: Participants receive routine swallowing rehabilitation training only.~Details of training: The training includes standard techniques to improve swallowing function, such as oral motor training, empty swallowing exercises, and ice stimulation. The frequency and duration of training are consistent across all participants in this arm to ensure standardization."