An observational study in Multiple Sclerosis, sponsored by University of Catania. Not yet recruiting at 1 site in Italy. Open to female participants aged 18 Years to 55 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-05-12.
Sponsored by University of Catania · Observational
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.
3,460 studies on the registry are indexed under Multiple Sclerosis; 661 are open to participants now.
This study's planned enrollment of 200 is above the median of 100 across 1,016 observational studies indexed under Multiple Sclerosis.
Browse Multiple Sclerosis studies →University of Catania is the lead sponsor of 68 studies on the registry; 14 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Number of participants: 400, 200 healthy controls, and 200 patients diagnosed with multiple sclerosis divided as follow: 100 with manifest trigeminal pain 100 without known trigeminal pathology.
Adult women (age 18 to 55) diagnosed with multiple sclerosis using the 2017 McDonald Criteria under treatment with Disease Modifying Therapy (DMTs) with or without trigeminal concerns, or newly diagnosed with MS
Exclusion Criteria:
Healthy patients
Diagnostic Test: TDI · Diagnostic Test: Trigeminal Test · Diagnostic Test: Visual Analogue Scale Ratings · Diagnostic Test: Quality of smell Questionnaire
Patients with multiple Sclerosis and Trigeminal disorders
Diagnostic Test: TDI · Diagnostic Test: Trigeminal Test · Diagnostic Test: Cognitive Evaluation by Montreal Cognitive Assessment · Diagnostic Test: Anxiety and Depression questionnaire · Diagnostic Test: Visual Analogue Scale Ratings · Diagnostic Test: Quality of smell Questionnaire
Patients with Multiple Sclerosis without trigeminal concerns
Diagnostic Test: TDI · Diagnostic Test: Trigeminal Test · Diagnostic Test: Cognitive Evaluation by Montreal Cognitive Assessment · Diagnostic Test: Anxiety and Depression questionnaire · Diagnostic Test: Visual Analogue Scale Ratings · Diagnostic Test: Quality of smell Questionnaire
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
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
Plan to share: Undecided — History collection Magnetic Resonance Imaging (MRI) 1.5-T Signal scanner; Whole brain scan; T2 FLAIR and double-echo long-TR axial, 3-mm axial and 1mm coronal slices; Olfactory bulb volumetrics "Sniffin' Sticks" Threshold and Identification Test Perform monorhinal Visual Analogue Scale Ratings 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) Quality of smell Questionnaire Cognitive Evaluation by Montreal Cognitive Assessment Anxiety and Depression questionnaire Trigeminal Lateralization
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University of Catania