Effects of “trigeminal training” on trigeminal sensitivity and self-rated nasal patency

Abstract

PurposePatients with the feeling of a congested nose not always suffer from an anatomical obstruction but might just have a low trigeminal sensibility, which prevents them from perceiving the nasal airstream. We examined whether intermittent trigeminal stimulation increases sensitivity of the nasal trigeminal nerve and whether this effect is accompanied by subjective improvement of nasal breathing.MethodThirty-five patients (Mage = 58.4 years; SD = 14.8; Minage = 21 years; Maxage = 79 years; 43% females) and 30 healthy controls (Mage = 36.7 years, SD = 14.5; Minage = 20 years; Maxage = 73 years; 60% females) participated in a study comprised of two sessions separated by “trigeminal training”. During each session, trigeminal sensitivity towards CO2, trigeminal lateralization abilities and ratings of nasal patency were assessed. Age and training compliance were controlled.Results“Trigeminal training” had a positive effect on trigeminal sensitivity in both groups, (p = .027) and this effect depended on the training compliance (p < .001). “Trigeminal training” had no effect on lateralization abilities of the subjects (p > .05). Ratings of nasal patency increased in patients (p = .03), but not in controls.Conclusions“Trigeminal training” consisting of intermittent presentation of diverse stimulants leads to an increase of trigeminal sensitivity, but this effect depended on the training compliance. Importantly, in patients, this training is also associated with an increase in self-rated nasal patency.

Trigeminal endonasal perception – an outcome predictor for septoplasty

“…Especially Eccles et al analysed the positive effect of menthol stimulating trigeminal perception and improving subjective sensation of nasal airflow without altering inner nasal space (7,21) . "Trigeminal training" may even improve CO2 sensitivity and the feeling of nasal patency, while not having a relevant impact on lateralisation scores (22) . In contrast, altering inner nasal space, as mentioned above, does not always improve subjective sensation of nasal airflow (6,18) .…”

Patients with COVID-19-associated olfactory impairment also show impaired trigeminal function

“…The patients were asked to rate their subjective ability to smell and taste on an analogue scale of 1-10 (1 = bad, 10 = good). In addition, the subjective patency of the nose was asked about via a 5-point scale, as nasal patency is a barometer of trigeminal sensitivity [5].…”

Improved Odor Identification Ability and Increased Regional Gray Matter Volume After Olfactory Training in Patients With Idiopathic Olfactory Loss

“…For example, the long duration of training increases the chances of losing participants with the attrition rate as high as 45% in some 6-month studies (Lamira et al, 2019), although this was not the case in the present study. Compliance is important as one recent study of trigeminal training showed that the correlation between training time and improvement of trigeminal sensitivity became insignificant after controlled for the compliance (Oleszkiewicz et al, 2018). Although the actual compliance was assumed to be highly based on the personal interviews with the patients following OT, the inclusion of training diaries or a modified training device (Saatci et al, 2020) should be considered in future research.…”