Intraductal Botulinum Toxin Is Safe for Managing Salivary Disorders

How effective and safe is a single-gland intraductal salivary infusion with onabotulinumtoxinA (BTXA) in the management of salivary disorders?

Bottom Line: The intraductal route of botulinum toxin delivery to salivary glands was without complication and was effective in two patients treated therapeutically. Pressure measurements during infusion may be helpful to direct treatment.

Background: Intraglandular injection of botulinum neurotoxin (BTX) is designed to decrease the cholinergic neural stimulus to salivary glands through the process of “chemical
denervation.” Despite limited FDA approval, BTX has been used extensively in salivary disorder management associated with a diverse array of diagnoses in pediatric and adult populations. Intraductal infusion to the salivary glands is performed in the course of conventional sialography, and has the capacity to deliver contrast agents not only to the salivary acini, but also through the acini with what has been termed “parenchymal clouding.”

Study design: Evaluation of two patients using interviews, clinical examination, and pressure measurement during infusion; retrospective chart review of two subsequently treated patients with a parotid-cutaneous fistula and sialorrhea.

Setting: Department of Otolaryngology–Head and Neck Surgery, University of Iowa Hospitals and Clinics, Iowa City.

Synopsis: The two patients assessed showed no complications from 25 units of BTXA infused into the right parotid gland (patient #1) and the left submandibular gland (patient #2). Patient #2 reported that the discomfort experienced in the left submandibular gland as it was expanded in the course of infusion rapidly dissipated by pausing during the otherwise continuous infusion. Following completion of the prospective study of the two initial patients, selected patients were offered intraductal BTXA infusion. Patient #3 was evaluated with a sialogram, which identified the parotid cutaneous fistula with an otherwise normal ductal system without stricture. Initial treatment with ultrasound-guided percutaneous intraglandular injection delivered 50 units of BTXA (in 2.0 cc) to the right parotid gland. The patient reported an initial impression of decreased fistula output that was not realized until one month after the injection. Three and one-half months after percutaneous injection, intraductal infusion to the right parotid gland was performed with BTXA (50 units in 2 cc) followed by 6 cc of saline. Two weeks post-treatment, the patient reported that the result was “95% good.” Patient #4 was initially treated with intraductal infusions of 25 units of BTXA to each submandibular gland followed by infusion of saline (2 cc to right, 3 cc to left). Despite the patient’s subjective lack of benefit, a six-week
follow-up examination revealed only scant saliva expressible from the submandibular glands with massage (previously robust).

Limitations included the retrospective analysis of treatment efficacy limited to only two patients.

Citation: Schwalje AT, Hoffman HT. Intraductal salivary gland infusion with botulinum toxin. Laryngoscope Investig Otolaryngol. 2019;4:520–525.