From a theoretically point of view pain in the trigeminal nerve increases the surrounding perception, including the perception of the odors. It has been shown that by using sweet food it is possible to reduce the level of pain; on the other side, sweet food in contrast to the bitter one was able to reduce the sensation of odor unpleasantness present with pain increase.
To date no studies have investigated the relationship between trigeminal inflammation, odors and pain in a cohort of patients with MS. This study aims at investigating the possible correlation between alteration in trigeminal functions and perception of odors using Sniffin' Stick Threshold, Detection and Identification test and quality smell questionnaire in a sample of healthy patients compared to MS patients.