A Novel Device for the Clinical Assessment of Intranasal Trigeminal Sensitivity

Abstract

Objective: Despite the significance of trigeminal pathology, practical clinical tests that accurately evaluate intranasal trigeminal function are scarce. The aim of the present study is to introduce a practical procedure for the assessment of intranasal trigeminal sensitivity. Methods: We developed a device to stimulate the nasal mucosa using carbon dioxide, which is self-administered intranasally by holding down a timed button until the required sensory response has been triggered. The trigeminal sensitivity is derived from the measured administration time in conjunction with the concentration of carbon dioxide administered. Sixty-three healthy participants were used to validate the device, after which the new device was compared with a standard lateralization task in an additional 16 participants. In 20 participants, the experiment was repeated to verify test-retest reliability. Results: Statistical analysis showed significant consistency in administration-duration in healthy individuals, including those in the test-retest group. Those participants with higher scores in the lateralization task were found to show higher intranasal sensitivity measured by the new device. Conclusion: Herein, we present the design and validation of a novel device for the practical assessment of intranasal trigeminal sensitivity. In this study, we demonstrate the efficacy and reliability of this device.

Automated assessment of intranasal trigeminal function

“…This effect was significant (t139 = 3.30, p = 0.001) although patients were also significantly older than controls (controls: The most important result from this series of experiments is that the current approach allows to assess CO 2 pain responsiveness in a reliable manner. Although other techniques ultimately provide similar results (e.g., (17,(24)(25)(26)(27); for review see (11) ) it is important to note that the current approach takes little time and is more or less self-organized by the subject. In addition, costs for producing such a device are low, especially as no dilution of CO 2 Is required but 100% v/v CO 2 is only presented in stimuli of various durations which simplifies stimulus control.…”

European position paper on diagnostic tools in rhinology

“…This test takes advantage of the fact that the olfactory system is unable to locate the source of stimulation whereas the trigeminal system can (187) . The third, most recently developed device uses the summation properties of the trigeminal system and analyses the concentration a subject is able to bear over time when exposed to a trigeminal stimulus such as carbon dioxide (188,189) . There is a need for better intranasal trigeminal testing since none of these methods has yet found its way into routine rhinology workup.…”

Assessment of Intranasal Function of the Trigeminal Nerve in Daily Clinical Practice

“…Various methods have been described for assessing intranasal trigeminal function, including psychophysical, electrophysiological (event-related potentials, negative mucosal potentials, and magnetoencephalography), imaging techniques (functional magnetic resonance imaging to measure the ratio of oxygenated haemoglobin/ deoxygenated haemoglobin in the brain and rarely PET), reflexes (pupillary responses to intranasal trigeminal stimulation), and changes in respiration (trigeminally induced breathing changes during deep and moderate propofol-induced sedation and apnoea threshold elevation in the elderly) [1,3,[17][18][19][20][21][22][23][24]. However, in this review, our focus is on measurement techniques that can be easily applied by the majority of rhinology clinics providing relatively quick information about intranasal trigeminal function.…”