Effect of Blue Light on Vagus Nerve Stimulation in Patients With Refractory Epilepsy (BLUELIGHTVNS)

Vagus nerve stimulation (VNS) is an adjunctive treatment for refractory epilepsy. Although widely used, there is still a substantial number of patients with insufficient response. Light, and particularly blue light, can stimulate alertness, attention and cognition through modulation of anatomical targets which are common to the vagal afferent network. This project aims at understanding how exposure to blue enriched light may influence VNS effects in patients with refractory epilepsy by exploring the modulation of a series of biomarkers of VNS action. This could possibly lead to new therapeutic strategies to increase efficacy of VNS.

Study Overview

• Status: Recruiting
• Conditions: Refractory Epilepsy
• Intervention / Treatment: Other: electroencephalography, electrocardiogram, pupillometry, evoked potentials, light administration; Other: transcutaneous vagus nerve stimulation, electroencephalography, pupillometry, electrocardiogram, light administration

• Study Type: Interventional
• Enrollment (Estimated): 34
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Inci cakiroglu; Phone Number: +32470612917; Email: inci.cakiroglu@uclouvain.be

Study Locations

• Belgium
  • Woluwe-Saint-Lambert, Belgium, 1200
    • Recruiting
    • Cliniques Universitaires Saint Luc
    • Contact: Inci Cakiroglu, Phd student; Phone Number: +32470612917; Email: inci.cakiroglu@uclouvain.be
    • Sub-Investigator: Inci Cakiroglu, Phd student

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

Patients:

VNS implanted since at least 3 months age >18-60 years; IQ >55 on Wechsler scale (normal status or mild cognitive impairment)

healthy participants aged between 18 and 35 years without any medical history (neurological / psychiatric disease)

Exclusion criteria:

Patients:

other medical implanted devices than VNS, ocular diseases

Helthy participants:

medical implanted devices, cerebral trauma, ocular disease

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Non-Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Patients with refractory epilepsy; Patients will not receive any drugs, but will participate to experiments involving electroencephalograpy, pupillometry and light administration.	Other: electroencephalography, electrocardiogram, pupillometry, evoked potentials, light administration; Recording of the electrical activity of the brain, of the heart. Pupil size will be analyzed. The effect of blue light administration will be assessed on those parameters.
Experimental: Healthy subjects; Subjects will not receive any drugs, but will participate to experiments involving electroencephalograpy, pupillometry and light administration.	Other: transcutaneous vagus nerve stimulation, electroencephalography, pupillometry, electrocardiogram, light administration; Transcutaneous vagus nerve stimulation will be performed in helathy subjects, as well as the recording of the electrical activity of the brain, and of the heart. Pupil size will be analyzed. The effect of blue light administration will be assessed on those parameters.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Effect of blue light on VNS biomarkers	Blue light increases VNS induced electroencephalogram desynchronisation in implanted patients	4 years
Effect of blue light on VNS biomarkers	Blue light increases P300 amplitude in VNS implanted patients	4 years
Effect of blue light on VNS biomarkers	Blue light increases VNS (or tVNS) induced pupil dilation (in patients & healthy subjects).	4 years

Collaborators and Investigators

• Sponsor: Cliniques universitaires Saint-Luc- Université Catholique de Louvain

Study record dates

Study Major Dates

• Study Start (Actual): July 1, 2023
• Primary Completion (Actual): July 1, 2023
• Study Completion (Estimated): April 1, 2026

Study Registration Dates

• First Submitted: April 18, 2023
• First Submitted That Met QC Criteria: March 4, 2024
• First Posted (Actual): March 12, 2024

Study Record Updates

• Last Update Posted (Estimated): September 10, 2025
• Last Update Submitted That Met QC Criteria: September 3, 2025
• Last Verified: September 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Epilepsy; Drug Resistant Epilepsy; Musculoskeletal and Neural Physiological Phenomena; Physiological Phenomena; Cortical Excitability; Electrophysiological Phenomena; Nervous System Physiological Phenomena; Evoked Potentials
• Other Study ID Numbers: BLUELIGHT-VNS

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No