Effect of somatosensorial stimulation on tinnitus
Dilara Bayazıt1, Gül Ölçek2, Oğuz Yılmaz3, Yuşa Başoğlu1
1İstanbul Medipol Üniversitesi, Sağlık Bilimleri Enstitüsü, Odyoloji Anabilim Dalı, İstanbul, Türkiye
2İstanbul Medipol Üniversitesi, Sağlık Bilimleri Fakültesi, Odyoloji Anabilim Dalı, İstanbul, Türkiye
3İzmir Bakırçay Üniversitesi, Sağlık Bilimleri Fakültesi, Odyoloji Anabilim Dalı, İzmir, Türkiye
Keywords: Residual inhibition, somatosensory, tinnitus, trigeminal nerve.
Abstract
OBJECTIVE: This study aimed to investigate the effects of trigeminal nerve (TN)-related somatosensory stimulation on the psychoacoustic parameters of tinnitus.
METHODS: This prospective observational study was conducted at the Audiology Unit of İstanbul Medipol University Hospital between August 01, 2021 and April 01, 2022. Twenty-eight patients (21 females, 7 males; mean age: 39±0.5 years; range, 18 to 65 years) with unilateral subjective tinnitus were included. The patients underwent psychoacoustic assessments under five conditions: the standard model, the mastoid model, and trigeminal stimulation at the ophthalmic (V1; forehead), maxillary (V2; maxilla), and mandibular (V3; preauricular) branches of the TN. Pitch matching, loudness matching, minimum masking level (MML), and residual inhibition (RI) were measured in each condition.
RESULTS: Significant correlations were observed between psychoacoustic parameters across different models (p<0.05). Tinnitus pitch did not differ significantly between models (p>0.05). Loudness and MML values were significantly higher in the standard model compared to other models (p<0.05). Residual inhibition rates in the preauricular (V3) model did not significantly differ from the standard model (p>0.05), despite lower MML values. The tinnitus intensities and MMLs measured in the standard model were significantly higher than the other models (p<0.05). The RIs of preauricular model was not significantly different from the other models (p>0.05). Similar RI rates were measured despite the lower MML levels in the preauricular model in comparison with the standard model.
CONCLUSION: Somatosensory stimulation via the V3 branch of the TN may influence tinnitus loudness and MML without altering pitch perception. The preauricular model may serve as an alternative to the standard model, offering similar RI outcomes at lower MMLs. This approach could be particularly advantageous in patients with conductive hearing pathologies such as chronic otitis media, otosclerosis, or aural atresia.