Effect of Visual Retraining on Visual Loss Following Visual Cortical Damage

NCT ID: NCT05098236

Last Updated: 2024-11-13

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 280 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2003-09-26
• Study Completion Date: 2024-06-04

Brief Summary

This project is intended to collect data using standard clinical tests and psychophysics to quantify the effect of visual cortical damage on the structure of the residual visual system, visual perception, spatial awareness, and brain function. The investigators will also assess the effect of intensive visual retraining on the residual visual system, processing of visual information and the use of such information in real-world situations following damage. This research is intended to improve our understanding of the consequences of permanent visual system damage in humans, of methods that can be used to reverse visual loss, and of brain mechanisms by which visual recovery is achieved.

Conditions

Vision Loss Partial; Hemianopia; Hemianopia Homonymous; Quadrantanopia; Stroke, Ischemic

Study Design

• Allocation Method: NON_RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: NONE

Study Groups

Cortically Blind Subjects

Group Type: EXPERIMENTAL

Training in the Blind Field

Intervention Type: OTHER

A computer software and chin-rest necessary to perform visual training will be loaned to each subject to be used at home. Subjects will perform one to two daily training sessions in their home, consisting of 200-300 trials each. The visual task performed repetitively will involve discriminating the direction of motion, the presence of motion, or the orientation of a visual stimulus (either a small cloud of dots or bars) located at a predetermined location in the blind field. The computer program will automatically create a record of patient performance during each home training session. Subjects will train daily (about 40-60 minutes total), 5 to 7 days per week for at least 3 and up to 12 months at a time.

Control

Group Type: PLACEBO_COMPARATOR

Training in the Sighted Field

Intervention Type: OTHER

This training will take place in lab at the University of Rochester Medical Center. Subject will perform one daily training session, consisting of 200-300 trials each. The visual task performed repetitively will involve discriminating the direction of motion, the presence of motion, or the orientation of a visual stimulus (either a small cloud of dots or bars) located at a predetermined location in the visual field. The computer program will automatically create a record of patient performance during each training session. Subjects will train daily (about 30-40 minutes total), 5 to 7 days per week for at 7 - 14 days.

Interventions

Training in the Blind Field

A computer software and chin-rest necessary to perform visual training will be loaned to each subject to be used at home. Subjects will perform one to two daily training sessions in their home, consisting of 200-300 trials each. The visual task performed repetitively will involve discriminating the direction of motion, the presence of motion, or the orientation of a visual stimulus (either a small cloud of dots or bars) located at a predetermined location in the blind field. The computer program will automatically create a record of patient performance during each home training session. Subjects will train daily (about 40-60 minutes total), 5 to 7 days per week for at least 3 and up to 12 months at a time.

Intervention Type: OTHER

Training in the Sighted Field

This training will take place in lab at the University of Rochester Medical Center. Subject will perform one daily training session, consisting of 200-300 trials each. The visual task performed repetitively will involve discriminating the direction of motion, the presence of motion, or the orientation of a visual stimulus (either a small cloud of dots or bars) located at a predetermined location in the visual field. The computer program will automatically create a record of patient performance during each training session. Subjects will train daily (about 30-40 minutes total), 5 to 7 days per week for at 7 - 14 days.

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• Subjects between the ages of 17 and 75, who have sustained damage to primary visual cortex at age 17 or later, and are rendered blind over a portion of their visual field.
• Subjects must have some intact visual cortical areas (other than primary visual cortex) in the damaged brain hemisphere. This assessment will be made from MRI or CT scans of the subject's head, which will be obtained via standard release from their neurologist.
• Subjects who demonstrate a clear deficit in either simple or complex visual perception in portions of their visual field.
• Subjects who are competent and responsible, as determined by the Principal Investigator.
• Subjects who will receive retinal electrophysiology (mfERG) testing must have a report from their ophthalmologist stating that they are able to receive dilating drops

• Subjects must be between the ages of 17 and 75 years of age
• Subjects must report no history of neurological disorder.
• Subjects who are competent and responsible, as determined by the Principal Investigator.

Exclusion Criteria

• Subjects who do not possess damage of primary visual cortex or its immediate afferents
• Subjects who are suffering from an active disease process involving their nervous system.
• Subjects who are unable to fixate visual targets precisely with their eyes
• Subjects who have unreliable vision fields from prior testing indicated by greater than 20% fixation losses, false positives or false negatives
• Best corrected visual acuity worse than 20/40 in either eye
• Impaired foveal sensitivity as indicated by visual field tests
• Presence of vision loss from ocular disease or disorder
• Presence of bilateral visual acuity loss from any source
• Subjects who are suffering from one-sided attentional neglect
• Subjects who have impaired auditory thresholds that would influence test results and training efficacy (all our testing and training involves sound as a cue for trial/stimulus onset or as feedback)
• Persons who lack the competence or are otherwise unable to perform the visual training exercises as directed.

• Subjects who possess damage to the visual system
• Subjects who are suffering from an active disease process involving their nervous system.
• Subjects who are unable to fixate visual targets precisely with their eyes
• Best corrected visual acuity worse than 20/40 in either eye
• Presence of vision loss from ocular disease or disorder
• Presence of bilateral visual acuity loss from any source
• Subjects who are suffering from one-sided attentional neglect
• Subjects who have impaired auditory thresholds that would influence test results and training efficacy (all our testing and training involves sound as a cue for trial/stimulus onset or as feedback)
• Persons who lack the competence or are otherwise unable to perform the visual testing/training exercises as directed.

• Minimum Eligible Age: 17 Years
• Maximum Eligible Age: 75 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

National Eye Institute (NEI)

NIH

Sponsor Role: collaborator

University of Rochester

OTHER

Sponsor Role: lead

Responsible Party

Krystel Huxlin

Professor

Responsibility Role: PRINCIPAL_INVESTIGATOR

Locations

Flaum Eye Institute, University of Rochester Medical Center

Rochester, New York, United States

Countries

United States

Other Identifiers

R01EY027314

Identifier Type: NIH

Identifier Source: secondary_id

View Link

STUDY00000075

Identifier Type: -

Identifier Source: org_study_id