Evaluation of ethanolamine oleate sclerotherapy on the submandibular glands of canines as a potential therapy for sialorrhea

BackgroundSialorrhea can have major negative effects on the physical and social well-being. Sclerotherapy may be useful in patients with sialorrhea by decreasing the amount of saliva production. The aim of this study was to test the effect of ethanolamine oleate (EO) in an experimental model as a preliminary step for its application in humans.MethodsHistopathological and morphometric analysis of submandibular glands from thirteen dogs was preformed. A total of 25 glands were injected with 1 ml of 2.5% EO (n = 5), 1 ml of 5% EO (n = 5), 5 ml of 2.5% EO (n = 5) and 5 ml of 5% EO (n = 5). Five glands were used as control.ResultsEO significantly induced a dose dependent scaring of the gland ending in lobular transformation (salivary gland cirrhosis). Morphometric measurements showed that 1 ml of 2.5% or 5% EO significantly induced fibrosis compared to normal glands (p = 0.014 and 0.021, respectively). Fibrosis significantly increased and was more apparent when a dose of 5 ml of 2.5% EO or 5% EO were injected [by semi-quantitative evaluation (p = 0.016 and 0.002, respectively) and morphometric measurements (p = 0.016 and 0.008, respectively)]. This scarring effect was significantly associated with reduction of area of acinar cells when a dose of 1 ml-5%, 5 ml-2.5% or 5 ml-5% EO were applied (p = 0.03. 0.012 and 0.004, respectively). Moreover, ductal injury was only significant when a dose of 5 ml of 5% EO was used (p = 0.034). This dose and concentration (i.e. 5 ml-5% EO) had a significant synergetic effect [p = 0.0119].ConclusionIn this model, treatment with EO proved to permanently reduce the acinar area through induction of progressive, irreversible and dose dependant scarring (medical sialoadenectomy).