Objectively Diagnose and Monitor Treatment of Light Sensitivity

NCT ID: NCT03694626

Last Updated: 2025-11-24

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

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Recruitment Status

RECRUITING

Clinical Phase

NA

Total Enrollment

120 participants

Study Classification

INTERVENTIONAL

Study Start Date

2019-07-11

Study Completion Date

2028-01-01

Brief Summary

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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.

Detailed Description

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Using objecting measurement of facial features, pupil responses, retinal electrical responses and autonomic nerve responses to light this project aims to provide a new framework for diagnosing and monitoring treatment of light sensitivity. The patient's responses will be measured with videography facial muscle electrical responses Electromyogram (EMG) measured from surface skin electrodes and retinal electrical responses (EMG) or electroretinogram (ERG) recorded from a portable hand-held device). Simultaneously, patient's will have their heart rate and skin conductance objectively monitored using wristwatch devices (E4, Empatica). If successful, this will open an immediate new way to objectively assess the mechanisms that lead to light sensitivity, and provide an approach to effectively treat, and manage the symptoms of light sensitivity and headache from different causes, including traumatic brain injury (TBI) and migraine.

Conditions

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Photophobia Traumatic Brain Injury Migraine

Study Design

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Allocation Method

NON_RANDOMIZED

Intervention Model

PARALLEL

Primary Study Purpose

SCREENING

Blinding Strategy

NONE

Study Groups

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Healthy Control subjects

Group Type ACTIVE_COMPARATOR

Pupillography

Intervention Type DEVICE

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)

Intervention Type DEVICE

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

Intervention Type 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

Intervention Type DEVICE

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

Intervention Type DEVICE

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.

TBI Patients without photosensitivity

Group Type ACTIVE_COMPARATOR

Pupillography

Intervention Type DEVICE

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)

Intervention Type DEVICE

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

Intervention Type 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

Intervention Type DEVICE

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

Intervention Type DEVICE

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.

Migraine patients without photosensitivity

Group Type ACTIVE_COMPARATOR

Pupillography

Intervention Type DEVICE

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)

Intervention Type DEVICE

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

Intervention Type 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

Intervention Type DEVICE

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

Intervention Type DEVICE

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.

Migraine patients with photosensitivity

Group Type ACTIVE_COMPARATOR

Pupillography

Intervention Type DEVICE

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)

Intervention Type DEVICE

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

Intervention Type 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

Intervention Type DEVICE

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

Intervention Type DEVICE

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.

TBI patients with photosensitivity

Group Type ACTIVE_COMPARATOR

Pupillography

Intervention Type DEVICE

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)

Intervention Type DEVICE

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

Intervention Type 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

Intervention Type DEVICE

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

Intervention Type DEVICE

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.

Interventions

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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.

Intervention Type DEVICE

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.

Intervention Type DEVICE

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).

Intervention Type DEVICE

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.

Intervention Type DEVICE

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.

Intervention Type DEVICE

Other Intervention Names

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Reteval, LKC (E4, Empatica)

Eligibility Criteria

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Inclusion Criteria

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


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


* 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)


* 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, 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:


* 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)


* 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


\- 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
Minimum Eligible Age

18 Years

Maximum Eligible Age

80 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

Yes

Sponsors

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Randy Kardon

OTHER

Sponsor Role lead

Responsible Party

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Randy Kardon

Principal Investigator

Responsibility Role SPONSOR_INVESTIGATOR

Locations

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University of Iowa Health Care

Iowa City, Iowa, United States

Site Status RECRUITING

Countries

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United States

Central Contacts

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Julie Nellis, BSN

Role: CONTACT

319-356-2780

Jan Full, BSN

Role: CONTACT

3193562780

Other Identifiers

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201604763

Identifier Type: -

Identifier Source: org_study_id

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