Recruiting

Observational Study

Sponsor:

Randy Kardon

Code:

NCT03694626

Conditions

Photophobia

Traumatic Brain Injury

Migraine

Eligibility Criteria

Sex: All

Age: 18 - 70+

Healthy Volunteers: Accepted

Interventions

Pupillography

Ocular Coherence Tomography (OCT)

Wrist-watch sensor device

Videography

Electrophysiology

Study Details

Brief summary:

The purpose of this project is to provide a new framework for diagnosing and monitoring treatment of light sensitivity and headache by objective measurement of facial features, pupil responses, retinal electrical responses and autonomic nerve responses to light.

Conditions

Photophobia

Traumatic Brain Injury

Migraine

Study ID

NCT03694626

Start date

Jul 11, 2019

Status verified date

Sep, 2026

Completion date

Jan 1, 2028

Anticipated

Primary completion date

Jan 1, 2028

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18 - 70+

Healthy Volunteers: Accepted

Healthy Control subjects:

Inclusion Criteria

  • Healthy individuals with normal eye exam in the previous year
  • Age 18-80

Exclusion Criteria

  • History of eye or systemic disorder that affect the retina, optic nerve, visual pathway, or pupil defect: including glaucoma, optic neuropathy, or retinal disease, diabetes and/or hypertension that are not well controlled, history of head trauma, concussion, or TBI, history of cervical or spinal injury/surgery
  • Medications or eyedrops that would confound measuring the pupil light reflex and EMG: including topical autonomic drugs that could influence pupil size, ocular pharmacologic agents, sedative agents (e.g. benzodiazepines or barbiturates), opioid narcotics
  • Must not be light sensitive or get migraine headaches

TBI patients without photosensitivity or headache:

Inclusion Criteria

  • Age 18-80
  • Traumatic Brain Injury (TBI)

Exclusion Criteria

  • History of eye or systemic disorder that affect the retina, optic nerve, visual pathway, or pupil defect: including glaucoma, optic neuropathy, or retinal disease, diabetes and/or hypertension that are not well controlled
  • Medications or eyedrops that would confound measuring the pupil light reflex and EMG: including topical autonomic drugs that could influence pupil size, ocular pharmacologic agents, sedative agents (e.g. benzodiazepines or barbiturates), opioid narcotics - Must not be light sensitive or get migraine headaches (use headache criteria from Ana if we are including headaches)

Patients with photosensitivity from non-TBI causes Inclusion Criteria

  • Age 18-80
  • Photosensitivity: determined by patient reporting symptoms and there may or may not be an identified cause associated with their light sensitivity (i.e. history of uveitis, childhood exotropia, meningitis, radiation, tumor)

Exclusion Criteria

  • History of eye or systemic disorder that affect the retina, optic nerve, visual pathway, or pupil defect: including glaucoma, optic neuropathy, or retinal disease, diabetes and/or hypertension that are not well controlled, history of head trauma, concussion, or TBI, history of cervical or spinal injury/surgery
  • Medications or eyedrops that would confound measuring the pupil light reflex and EMG: including topical autonomic drugs that could influence pupil size, ocular pharmacologic agents, sedative agents (e.g. benzodiazepines or barbiturates), opioid narcotics

TBI patients with photosensitivity Inclusion Criteria

  • Age 18-80
  • Photosensitivity: determined by patient reporting symptoms and cause associated with their light sensitivity is post TBI
  • TBI

Exclusion Criteria

\- History of eye or systemic disorder that affect the retina, optic nerve, visual pathway, or pupil defect: including glaucoma, optic neuropathy, or retinal disease, diabetes and/or hypertension that are not well controlled

Study Design

Enrollment

120 participants

Anticipated

Allocation

Non randomized

Intervention Model

Parallel Assignment

Primary purpose

Screening

Interventions and Outcome Measures

Arms

active comparator: Healthy Control subjects

active comparator: TBI Patients without photosensitivity

active comparator: Migraine patients without photosensitivity

active comparator: Migraine patients with photosensitivity

active comparator: TBI patients with photosensitivity

Interventions

Pupillography

A hand-held pupillometer/electroretinogram device (RETeval, LKC) will be held in front of the subject's eye, but will not touch the eye. The device will provide a brief, a series of brief light stimuli and then record the pupil response and the elicited electrical response from the retina from a surface skin patch (electrode) placed below each eye, from the light as a measure of whether the inherent sensitivity of the eye in the retina is normal. The investigators will repeat this in the left eye. The visible light stimulus is safe and is given at an intensity experienced in normal daily light exposures. The test takes about 2 minutes per eye.

Ocular Coherence Tomography (OCT)

The thickness of the optic nerve and macula will also be measured inside of the eye using a special camera that forms an image of the layers of the retina without pupil dilation. The imaging is harmless and measures the structural health of the optic nerve and retinal layers. This test takes 5-10 minutes per eye.

Wrist-watch sensor device

A wrist-watch sensor device (E4, Empatica) will be place on each wrist to measure skin conductance, heart rate, skin temperature and arm movement during testing. These wrist-watch devices are being used to monitor changes in sympathetic nerve activity to light intensity, (the sympathetic nerves supply the blood vessels to the skin and heart).

Videography

The subject will sit comfortably in front of miniature combination infrared/visible light video cameras and infrared diode light source located within 1 meter to provide video recording of the face during testing with light and during darkness, described next.

After the 10 minutes of dark-adapting, the subject will put his/her chin on a chin rest in front of the video cameras and a light emitting diode (LED) array give diffuse red, blue, and white stimuli over a range of intensities. None of the stimuli are as bright as a flash from a camera and are in the range of intensities normally experienced during daily activities.

At the end of the test the investigators will add filters over the glasses: orange (blue-blocking) filters and neutral density filters. Subjects will grade independently, both the brightness and discomfort they feel from each light stimulus intensity.

Electrophysiology

Next, electrodes will be placed above, below and to the side of the test eye to record the electromyogram (EMG) for measuring eyelid opening and blink rate.

Primary outcome measure

  • Correlation of facial responses to light sensitivity [ Time Frame: 1 Day ]
  • Difference in objective biological markers of light sensitivity between light sensitive and normal subjects [ Time Frame: 1 Day ]

Central Contacts and Locations

Central contacts

Julie Nellis, BSN

319-356-2780julie-nellis@uiowa.edu

Jan Full, BSN

3193562780jan-full@uiowa.edu

Locations

University of Iowa Health Care

Recruiting

Iowa City, Iowa, United States, 52242

More Information

Sponsor

Randy Kardon

Last update posted

Sep 8, 2026

Last verified

Sep, 2026

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-09. This information was provided to ClinicalTrials.gov by Randy Kardon on 2026-09-08.