Functional MRI Study of Cortical Modifications to Light Stimulation in Patients With Photophobia

Toulouse University Hospital

Status: Unknown

Conditions: Photophobia; Dry Eye Syndrome

Treatments: Radiation: fMRI

Study type: Interventional

Funder types: Other

Identifiers

NCT03464357

2017-A02601-52 (Other Identifier)

RC31/17/0275

Details and patient eligibility

About

Photophobia is a common and disabling symptom in patient with dry eye syndrome. The aim of this study is tried to better understand this complain analyzing brain activation during a luminous stimulation to highlight modification of cortical activation.

Full description

Dry eye syndrome is a frequent and underestimated disease whose incidence tends to increase because of the population ageing and behaviors modification (time spent using screens increased, wearing of contact lenses...). Photophobia deteriorates the quality of life in patients with dry eye syndrome decreasing outdoor activities. This symptom is not understood and does not seem to be linked with dry eye syndrome severity. The study will compare cortical activation after luminous stimulation of 16 patients eyes (8 patients with dry eye syndrome and photophobia vs 8 asymptomatic patients) using functional MRI (fMRI).

The primary study endpoint was the extent of magnetic signals in visual cortex after luminous stimulation. Secondary endpoints were the spatial activation extent in the 3 areas of the visual cortex (Brodmann areas 17,18,19).

Enrollment: 16 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Symptomatic subjects : presence of bilateral photophobia with an impact on daily activities (driving, outdoor activities, screens use, socio-professional activities...) in a context of patent dry eye syndrome
• Asymptomatic subjects : no dry eye syndrome and no photophobia
• Patients able to understand medical information and sign consent.

Exclusion criteria

• Ophthalmological pathologies of cornea, iris, optic nerve or retina
• MRI contraindications (metallic prosthesis, pacemaker, claustrophobia)
• Neurological pathology which may affect MRI results
• Subjects under legal protection

Trial design

Primary purpose: Other

Allocation: Non-Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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16 participants in 2 patient groups

Symptomatic patients with dry eye

Active Comparator group

Description:

8 symptomatic patients with dry eye (mild to severe) assessed using a validated questionnaire (OSDI score, Appendix 1) associated with a disabling photophobia (need to wear sunglasses permanently outside, restriction of the outputs in case of significant brightness, restriction of the use of the screens because of the visual embarrassment ...). The fMRI will be carried out following the inclusion visit after all the necessary checks

Treatment:

Radiation: fMRI

Asymptomatic patient

Active Comparator group

Description:

8 asymptomatic patients presenting neither photophobia (even minimal) or dry eye. The fMRI will be carried out following the inclusion visit after all the necessary checks

Treatment:

Radiation: fMRI