Measuring Relative Afferent Pupillary Defect

NCT05799066 | Active Not Recruiting

• 1 other identifier: 23-0023
• Study Type: interventional
• Target: 71
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this prospective reliability study is to test the effectiveness of a commercially available, off-the-shelf virtual reality head-mounted display (VR HMD) and machine learning (ML) algorithms in detecting Relative Afferent Pupillary Defect (RAPD) in a group of subjects with known RAPD and another group with no known RAPD. The main questions it aims to answer are:

• Does the use of the VR HMD and ML to replace the standard of care swinging flashlight test provide a more reliable and objective pupil measurement to detect RAPD?
• Can RAPD be detected by the VR HMD and ML algorithms at an earlier stage than the standard of care swinging light test? Participants will be asked to undergo the standard of care swinging flashlight test, have their pupils manually measured, then have the test repeated using the VR HMD and ML. Researchers will compare the measurements taken manually, following the standard of care swinging light test and those recorded by the VR HMD and ML to help answer the above questions.

Conditions

Relative Afferent Pupil Defect (RAPD)

Keywords

Relative Afferent Pupil Defect (RAPD); Pupil measurements; Swinging flashlight test; Pen light test; Virtual reality head mounted display (VR HMD); Visual loss; Vision loss; Afferent pupillary dysfunction; Pupillary light reaction; HTC Vive Pro Eye

Outcome Measures

Primary Outcomes (1)

• Pupillary measurements

  Measure of pupil size in each eye, measured manually or via machine learning algorithms

  Immediately following the swinging light test or VR HMD light test

Study Arms (2)

Known RAPD

EXPERIMENTAL

Participants with known RAPD will be administered the standard of care swinging light test and pupil measurements taken manually, then administered the light test using the VR HMD and ML.

Diagnostic Test: Swinging Light test; Diagnostic Test: Virtual Reality Head-Mounted Display (VR HMD)

No Known RAPD

EXPERIMENTAL

Participants with no known RAPD will be administered the standard of care swinging light test and pupil measurements taken manually, then administered the light test using the VR HMD and ML.

Diagnostic Test: Swinging Light test; Diagnostic Test: Virtual Reality Head-Mounted Display (VR HMD)

Interventions

Swinging Light test DIAGNOSTIC_TEST

The swinging light or pen light test with manual pupil measurements is the standard of care test for RAPD. This test consists of a light being shone in one eye for 3 to 4 seconds then shown in the other eye for 3 to 4 seconds, repeating 2 to 3 times. Pupils are measured manually immediately after the light test. Measurements are recorded in patient's medical record.

Also known as: Pen Light test

Known RAPD; No Known RAPD

Virtual Reality Head-Mounted Display (VR HMD) DIAGNOSTIC_TEST

A light is shone from within the VR HMD, pupillary measurements are taken and recorded by the machine learning (ML) algorithm.

Known RAPD; No Known RAPD

Eligibility Criteria

• Age: 18 Years - 85 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age 18 - 85
• patients with known RAPD.
• patients with no known RAPD
• May be diagnosed with a vision disorder such as glaucoma, diabetic retinopathy, unilateral or asymmetrical disease of the retina or other degenerative ocular diseases
• Referred to study by treating eye doctor
• Volunteered to participate in study
• UTMB clinic patients
• Not belonging to an identified vulnerable population

You may not qualify if:

• Younger than 18; older than 85 years of age
• Not a UTMB clinic patient
• Belonging to an identified vulnerable population
• Participants with discomfort using glasses
• Experience discomfort using VR HMD device
• Participants with history of congenital pupil defects, traumatic pupils
• Those whose pupils were dilated during the standard of care examination deemed by treating eye doctor not to be eligible to participate in study
• Participants who do not follow study directions and/or safety procedures given by investigators or lab assistants
• Participants who do not speak English to prevent a communication error during the informed consent process

Sponsors & Collaborators

• The University of Texas Medical Branch, Galveston: lead
• University of Nevada, Reno: collaborator

Study Sites (1)

University of Texas Medical Branch

Galveston, Texas, 77555, United States

Location

Related Publications (2)

• Vejdani MD., Al-Zubidi N. Relative Afferent Pupillary Defect. Eyewiki 2020. https://eyewiki.org/Relative_Afferent_Pupillary_Defect

  BACKGROUND

• Simakurthy S, Tripathy K. Marcus Gunn Pupil. 2023 Aug 25. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from http://www.ncbi.nlm.nih.gov/books/NBK557675/

  PMID: 32491607 BACKGROUND

MeSH Terms

Conditions

Pupil Disorders; Vision Disorders

Condition Hierarchy (Ancestors)

Neurologic Manifestations; Nervous System Diseases; Eye Diseases; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Sensation Disorders

Study Officials

• Kevin H Merkley, MD, MBA

  University of Texas

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: SCREENING
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: Group 1 will consist of individuals with known RAPD Group 2 will consist of individuals with no known RAPD

Study Record Dates

• First Submitted: March 22, 2023
• First Posted: April 5, 2023
• Study Start: May 4, 2023
• Primary Completion (Estimated): May 14, 2026
• Study Completion (Estimated): May 14, 2026
• Last Updated: May 16, 2025

Record last verified: 2025-05

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)