Pathophysiological Mechanisms of Trigeminal Neuralgia - Neurophysiological Assessment of the Blink-reflex

NCT05328661 | Completed

• 1 other identifier: DanishHC180322Blink
• Study Type: observational
• Target: 60
• Locations: 1 country
• Sites: 1

Brief Summary

This study aims to increase the understanding of the pathophysiology of trigeminal neuralgia by investigating the potential association between blink reflex abnormalities and phenotypical traits e.g. clinical characteristics and neuroimaging findings.

Conditions

Trigeminal Neuralgia

Outcome Measures

Primary Outcomes (1)

• Latency and amplitude of blink reflex on the pain side of classical trigeminal neuralgia patients.

  We place the stimulator above the emergence of the supraorbital nerve, with the distal pole placed below. The subject could be in a sitting or supine position. He keeps his eyes opened and relaxed. The final intensity of stimulation is generally between 5to 10mA, but higher intensities sometime are required. We don't start from this intensity, but we increase it gradually from 2mA, in steps of 1-2mA. The time between consecutive stimuli must not be under 45 seconds, in order to avoid habituation. Before the stimuli is delivered, we look at the real-time activity box to be sure that the subject is relaxed. We aim to record at least 2-3 consecutive sweeps with a stable latency of the R1 and R2 components.

  1 year

Secondary Outcomes (1)

• Latency and amplitude of blink reflex on the pain side of idiopathic trigeminal neuralgia patients

  1 year

Interventions

Blink reflex DIAGNOSTIC_TEST

The stimulator is directly connected to the right side of the frontal board. The sponge must be soaked in water or saline before being inserted into the stimulator. Dry them a bit to avoid leaking on the stimulator (it could create a bridge between the two poles). We want to stimulate the supraorbital nerve at its emergence from the eyebrow arch (the supraorbital foramen in the supra-orbital margin bone is easy to palpate 1 cm laterally to the root of the nose). We place the stimulator above the emergence of the supraorbital nerve, with the distal pole placed below. The final intensity of stimulation is generally between 5 to 10 mA, but higher intensities sometime are required.

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Trigemnal neuralgia patients either with classic or idopathic TN

You may qualify if:

• Age 18 years or older
• Must be able to give Signed Informed Consent prior to study entry. Appendix X
• Must fulfill the ICHD-3 diagnostic criteria1 for classical, idiopathic or secondary TN.
• Has had a 3.0 Tesla MRI according to the trigeminal neuralgia protocol, maximum 2 years before or after the assessment of the blink-reflex.
• Has had a semi-structured interview and neurological examination by the independent assessors, maximum 2 years before or after the assessment of the blink-reflex.

You may not qualify if:

• If the patient is not able to give informed consent due to mental challenges
• Previous neurosurgical treatment (microvascular decompression and/or ablative procedures) for trigeminal neuralgia
• Bilateral trigeminal neuralgia
• Symptomatic trigeminal neuralgia
• Findings of sensory abnormalities detected at clinical neurological examination

Sponsors & Collaborators

• Danish Headache Center: lead

Study Sites (1)

Danish Headache Center

Glostrup Municipality, 2600, Denmark

Location

Related Publications (1)

• Bjerring B, Maarbjerg S, Heinskou T, Bendtsen L, Nikolic M, Grillo V, Icco R, Schytz HW. Comparison of the blink reflex in classical and idiopathic trigeminal neuralgia. Cephalalgia. 2023 Jul;43(7):3331024231191136. doi: 10.1177/03331024231191136.

  PMID: 37525973 DERIVED

MeSH Terms

Conditions

Trigeminal Neuralgia

Interventions

Blinking

Condition Hierarchy (Ancestors)

Trigeminal Nerve Diseases; Facial Neuralgia; Facial Nerve Diseases; Mouth Diseases; Stomatognathic Diseases; Cranial Nerve Diseases; Nervous System Diseases

Intervention Hierarchy (Ancestors)

Reflex; Nervous System Physiological Phenomena; Musculoskeletal and Neural Physiological Phenomena; Ocular Physiological Phenomena

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Consultant in Neurology

Study Record Dates

• First Submitted: March 18, 2022
• First Posted: April 14, 2022
• Study Start: May 1, 2021
• Primary Completion: September 1, 2022
• Study Completion: December 1, 2022
• Last Updated: January 30, 2025

Record last verified: 2025-01

Data Sharing

• IPD Sharing: Will not share

Locations

DK (1)