Home-based Vision Therapy

Home-based Treatment of Binocular Eye Dysfunction in Veterans With Traumatic Brain Injury

Post-concussive vision symptoms affect many Veterans who have experienced traumatic brain injury (TBI). One common issue is trouble with near vision, a problem that may persist long after the acute injury. Double vision or difficulty focusing on close objects can affect reading and depth perception. Poor reading can interfere with academic or work performance, and loss of near focusing can affect jobs that require fine motor tasks like machining and electrical work. Even having trouble using a smartphone can have a substantial impact on both work and social function. Near vision impairment after TBI is not well understood, and treatments are limited. The goal of this project is to investigate novel virtual-reality assessments and training games to improve the near vision diagnosis and home-based rehabilitation. Restoring normal near vision function could have a large impact on the fulfillment of Veterans' educational, career, and overall life goals.

Study Overview

• Status: Recruiting
• Conditions: Convergence Insufficiency
• Intervention / Treatment: Other: Virtual-reality convergence training game

• Study Type: Interventional
• Enrollment (Estimated): 45
• Phase: Phase 1

Contacts and Locations

• Study Contact: Name: Mark F Walker, MD; Phone Number: 820 5225 (216) 791-3800; Email: Mark.Walker5@va.gov

Study Locations

• United States
  • Ohio
    • Cleveland, Ohio, United States, 44106-1702
      • Recruiting
      • Louis Stokes VA Medical Center, Cleveland, OH
      • Contact: Mark F Walker, MD; Phone Number: 820 5225 (216) 791-3800; Email: Mark.Walker5@va.gov
      • Principal Investigator: Mark F. Walker, MD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• U.S. Military Veteran
• Place of residence within driving distance of Cleveland, OH
• Clinical eye exam within 6 months prior to enrollment and since the most recent TBI (if applicable) and the onset of near vision symptoms (if applicable)
• Best-corrected visual acuity 20/25 or better in each eye
• Convergence insufficiency (VR-NPC < 32 deg)

Exclusion Criteria:

• Neurological condition other than TBI that would affect convergence
• History of strabismus, amblyopia, or other binocular vision issues prior to TBI

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Group A; Intervention block followed by non-intervention block	Other: Virtual-reality convergence training game; The participant plays a custom virtual-reality game that is designed to train convergence.
Experimental: Group B; Non-intervention block followed by intervention block	Other: Virtual-reality convergence training game; The participant plays a custom virtual-reality game that is designed to train convergence.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Vergence Capacity (VR-NPC)	The near point of convergence (angle of maximum ocular convergence) will be measured using a custom virtual-reality application.	At study onset, At completion of Block 1 (six weeks duration), At completion of Block 2 (six weeks duration)
System Usability Scale (SUS)	This is a standardized questionnaire to assess how easy a new technology is to use.	At completion of active treatment block (six-weeks duration)
Simulator Sickness Questionnaire (SSQ)	This is a standardized questionnaire to test the player's tolerance of the virtual-reality experience.	At completion of active treatment block (six-weeks duration)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Accommodation	Ocular accommodation (focus of the intraocular lens for near viewing) will be measured using the minus-lens method.	At study onset, At completion of Block 1 (six weeks duration), At completion of Block 2 (six weeks duration)
Dynamic Vergence	The accuracy and speed of fixation steps between virtual near and far targets is assessed.	At study onset, At completion of Block 1 (six weeks duration), At completion of Block 2 (six weeks duration)
Stereoacuity	Stereovision is assessed in virtual reality. Stereoacuity threshold is determined from a curve fit to the response data.	At study onset, At completion of Block 1 (six weeks duration), At completion of Block 2 (six weeks duration)
VR Word Reading: Word Accuracy Score	The accuracy and speed of word reading is assessed in response to lists of words presented to the participant in virtual reality. The Word Accuracy Score is the number of words read correctly minus errors.	At study onset, At completion of Block 1 (six weeks duration), At completion of Block 2 (six weeks duration)
VR Word Reading: Reading Speed Score	The accuracy and speed of word reading is assessed in response to lists of words presented to the participant in virtual reality. The Reading Speed Score is the Word Accuracy Score divided by total reading time.	At study onset, At completion of Block 1 (six weeks duration), At completion of Block 2 (six weeks duration)
WIAT Word Reading Tests: Word Accuracy Score	Participants read lists of words and nonsense words. The number of words read correctly is the accuracy score. Raw score will be converted to a standardized score (mean=100, S.D.=15) using normative data.	At study onset, At completion of Block 2 (six weeks duration)
WIAT Word Reading Test: Word Fluency Score	Participant reads lists of words and nonsense words. The number of words read correctly within 30 seconds is the fluency score. Raw score will be converted to a standardized score (mean=100, S.D.=15) using normative data.	At study onset, At completion of Block 2 (six weeks duration)
WIAT Oral Reading Fluency and Comprehension Test: Oral Reading Accuracy Score	Participant reads two passages aloud. The Oral Reading Accuracy Score is the number of words read minus errors (mispronunciations or additions). Raw score will be converted to a standardized score (mean=100, S.D.=15) using normative data.	At study onset, At completion of Block 2 (six weeks duration)
WIAT Oral Reading Fluency and Comprehension Test: Oral Reading Fluency Score	Participant reads two passages aloud. The Oral Reading Fluency Score is the Oral Reading Accuracy Score (Outcome #9) divided by the time needed to complete reading of the passage. Raw score will be converted to a standardized score (mean=100, S.D.=15) using normative data.	At study onset, At completion of Block 2 (six weeks duration)
Convergence Insufficiency Symptom Survey (CISS)	This is a standardized questionnaire to assess symptoms related to near vision.	At study onset, At completion of Block 1 (six weeks duration), At completion of Block 2 (six weeks duration)

Collaborators and Investigators

• Sponsor: VA Office of Research and Development
• Investigators: Principal Investigator: Mark F. Walker, MD, Louis Stokes VA Medical Center, Cleveland, OH

Study record dates

Study Major Dates

• Study Start (Actual): January 14, 2026
• Primary Completion (Estimated): September 30, 2028
• Study Completion (Estimated): September 30, 2028

Study Registration Dates

• First Submitted: March 7, 2025
• First Submitted That Met QC Criteria: March 13, 2025
• First Posted (Actual): March 20, 2025

Study Record Updates

• Last Update Posted (Actual): January 20, 2026
• Last Update Submitted That Met QC Criteria: January 15, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Keywords: Vision, Binocular; Convergence, Ocular
• Additional Relevant MeSH Terms: Central Nervous System Diseases; Nervous System Diseases; Eye Diseases; Cranial Nerve Diseases; Ocular Motility Disorders
• Other Study ID Numbers: N5317-R

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No