The Head Injury-associated Photosensitivity and Pupillary Function (HIPP) Study (HIPP)

After a head injury, many people find that exposure to light causes them increased discomfort. By measuring how the pupil in the eye constricts to flashes of red and blue light, this study will investigate whether this phenomenon is due to a change in the eye's sensitivity to light.

Study Overview

• Status: Completed
• Conditions: Head Injury; Photophobia; Photosensitivity; Traumatic Brain Injury (TBI)

Detailed Description

The pupils inside the eyes constrict in response to light stimulation. Different classes of cells within the human retina initiate this response. Recent research suggests that one of the ganglion cell types involved in this pupil response also plays a role in the photophobia experienced by migraine sufferers. The main aim of this study is to determine whether this type of ganglion cell becomes 'hypersensitive' after traumatic brain injury, thereby contributing to symptoms of increased photosensitivity experienced by many of these individuals.

In the first session of this study, subjects will be asked questions about their sensitivity to light and the reaction of their eyes' pupils to flashing red and blue lights will be measured. The subjects will be given a full eye examination to rule out other causes of increased photosensitivity.

In some cases, subjects will be asked to attend a second session roughly two weeks later. They will be asked to wear a watch that measures their daily activity/sleep rhythms and light exposure during this inter-session period. During the second session, further testing of the pupil responses to blue and red flickering light will be performed.

• Study Type: Observational
• Enrollment (Actual): 40

Contacts and Locations

Study Locations

• United States
  • Ohio
    • Columbus, Ohio, United States, 43210
      • College of Optometry

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Cases: Age 18 or older with symptoms of increased photosensitivity since experiencing a head injury.

Controls: Matched to cases in age, sex and race.

Description

Inclusion Criteria:

• 18+ years old
• reports a previous head injury that occurred at least 6 months ago
• score of 2 or 3 (mild TBI) on OSU-TBI ID Survey
• best-corrected visual acuity of at least 20/30 in both eyes
• reliable visual field

Exclusion Criteria:

• pregnancy
• significant afferent pupillary defect
• previous history of neurodegenerative disease
• intraocular pressure more than 21 mm Hg
• significant visual field defect
• active corneal pathology
• history of retinal or optic nerve disease
• strabismus (eye turn)

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
Case Subjects; Age 18 years or older; Had a head injury that occurred at least 6 months prior to entering study; Have found lights more bothersome since injury
Control Subjects; Age 18 years or older; Have not had a previous head injury; Have had a full eye examination at Ohio State University College of Optometry during last 6 months.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Pupil Responses	The pupil fluctuation evoked by blue and red flickering lights will be measured in patients with a prior brain injury and compared to matched controls.	2 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Sleep Rhythms	Daily rhythms of sleep and activity will be assessed in subjects with prior brain injury and compared to matched controls.	2 weeks
Light Exposure	The exposure to red, blue and green components of the light spectrum will be quantified in patients with a prior brain injury, and compared to matched controls.	2 weeks
Photosensitivity Symptoms	Subjects will complete survey indicating symptoms they have experienced related to light sensitivity and will grade their discomfort after exposed to brief flashes of light.	Single visit - one day

Collaborators and Investigators

• Sponsor: Ohio State University
• Collaborators: U.S. Army Medical Research and Development Command
• Investigators: Principal Investigator: Andrew Hartwick, OD, PhD, Ohio State University

Publications and helpful links

General Publications

• Barker F, Cockerham G, Goodrich G, Hartwick A, Kardon R, Mick AB, Swanson M. Brain Injury Impact on the Eye and Vision. Optom Vis Sci. 2017 Jan;94(1):4-6. doi: 10.1097/OPX.0000000000001001. No abstract available.
• Yuhas PT, Shorter PD, McDaniel CE, Earley MJ, Hartwick AT. Blue and Red Light-Evoked Pupil Responses in Photophobic Subjects with TBI. Optom Vis Sci. 2017 Jan;94(1):108-117. doi: 10.1097/OPX.0000000000000934.

Helpful Links

• Vision and Traumatic Brain Injury: The Outlook for Therapeutics - ARVO 2016 (Andrew Hartwick, speaker)

Study record dates

Study Major Dates

• Study Start: August 1, 2013
• Primary Completion (Actual): December 1, 2014
• Study Completion (Actual): December 1, 2015

Study Registration Dates

• First Submitted: September 6, 2013
• First Submitted That Met QC Criteria: September 13, 2013
• First Posted (Estimate): September 16, 2013

Study Record Updates

• Last Update Posted (Actual): September 25, 2017
• Last Update Submitted That Met QC Criteria: September 20, 2017
• Last Verified: September 1, 2017

More Information

Terms related to this study

• Keywords: traumatic brain injury; photosensitivity; photophobia; pupil
• Additional Relevant MeSH Terms: Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Skin Diseases; Eye Diseases; Neurologic Manifestations; Trauma, Nervous System; Sensation Disorders; Vision Disorders; Brain Injuries; Wounds and Injuries; Brain Injuries, Traumatic; Craniocerebral Trauma; Photophobia; Photosensitivity Disorders
• Other Study ID Numbers: 2013H0151; W81XWH-12-1-0434 (Other Grant/Funding Number: Telemedicine and Advanced Technology Research Center)