Qualitative and quantitative scintigraphy in sialorrhea before and after botulinum toxin injection.

OBJECTIVES/HYPOTHESIS: Sialorrhea is excessive saliva production and its usual escape of from the oral cavity. The use of botulinum toxin has been preconized, but its effectiveness until now has been unreliably measured. Our objective was to qualitatively and quantitatively determine the effectiveness of botulinum toxin injection in the reduction of saliva production by the parotid gland. STUDY DESIGN: Outcomes research. METHODS: Patients with moderate-to-critical sialorrhea had one of the parotid glands injected with 50 U of botulinum toxin, leaving the other as the control. Fifteen days after the toxin injection, they underwent scintigraphic analyses with intravenous injection of 10 mCi (37 MBq) of Tc-99 m (sodium pertechnetate). After this, the noninjected gland was treated for therapeutic complementation. RESULTS: The glands injected with botulinum toxin showed uptake reduction in 100% of patients. The uptake reduction in counts per second varied from 8% to 36%. The Wilcoxon paired test comparing the control glands with those injected showed a significant difference for the action of botulinum toxin (P = .0039). CONCLUSIONS: The scintigraphic study of parotid glands shows that botulinum toxin is effective in reducing sodium pertechnetate uptake. LEVEL OF EVIDENCE: 2c Laryngoscope, 129:2521-2526, 2019.