The sensation of smell is influenced by the somatosensory and chemesthetic sensati¬ons of the nose: for example, the cooling sensation of menthol or the prickle of carbon dioxide from carbonated drinks. These sensations are mediated in the nose by the trigeminal nerve and there is increasing evidence that trigeminal and olfactory functions are closely linked and potentially interdependent. In addition, trigeminal activation is crucial to the perception of nasal airflow. Some researchers speculate about the impact of trigeminal nerve on the entire olfactory sensation and about the presence of some specific "trigeminal cells" into the nose.Patients with Multiple sclerosis (MS) can suffer from quantitative olfactory disorders that generally are of light entity and do not interfere with daily life activities but it is important to underline that olfactory loss can be an onset sign of the MS. Considering the "trigeminal component" in the olfaction, because trigeminal nerve inflammation is quite common in MS patients due to central and peripheral inflammation, it could be possible that these patients suffer from changes in the quantitative, but more in the qualitative smell functions that are generally not identified because poorly investigated.
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.
Study Type
OBSERVATIONAL
Enrollment
200
Sniffin' Sticks Threshold and Identification Test
Test the trigeminal smell answer by a device that releases air and a substance that stimulates the trigeminal response
Montreal Cognitive assessment
Specific test to evaluate patient's mood
* Smell ability (How is your sense of smell right now? 0 cannot smell, 1-3 severe impairment, 4-6 moderate impairment, 7-9 mild impairment, 10 normal) * Nasal breathing (How well can you breathe through your nose right now? 0 complete nasal obstruction, 1-3 severe impairment, 4-6 moderate impairment, 7-9 mild impairment, 10 normal)
Patients will answer to a validated questionnaire
Arianna Di Stadio
Catania, Sicily, Italy
Trigeminal component
One bottle contains 10ml Eucalyptol (pure / 99%), the other bottle contains only air 15ml stimuli would be released from both bottles using the squeezer device A 3cm long, 4mm inner diameter silicon tubing is placed over the nozzle of each bottle to minimize irritation at the nostrils Silicon tubing should reach beyond the nasal valve area * Trigeminal intensity ratings (How intense is the tickling or cool sensation in the nose? 0 no feeling, 10 very strong feeling) * The trial can be done on the left nostril, then on the right nostril and this already corresponds to the first presentation for the actual test * Total of 20 presentations (10 on each side) with interstimulus interval of around 10 seconds between each presentation, and a longer pause of 30 seconds every 5 presentations * The score is the sum of correct lateralizations
Time frame: 12 months
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.