Vision Loss PartialNCT06352086
Understanding Visual Processing After Occipital Stroke
An observational study of Vision Loss Partial and Vision; Loss, Both Eyes, run by University of Rochester.
Trial summary
The purpose of this study is to investigate how visual orientation discrimination and metacognition (i.e., perceptual confidence) are affected by occipital stroke that causes hemianopia and quadrantanopia in adults. Read more about this study
- Who is it for?
- Ages 21 to 75 years
- Conditions the study is for
- Vision Loss Partial, Vision; Loss, Both Eyes, Hemianopia, Homonymous
- How many people
- 0 participants
- Where
- No sites listed yet
- Study dates
- Dec 2025to Sep 2029
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 21 to 75 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: Subjects will all be individuals who have sustained partial vision loss after an occipital lobe stroke.
Who may be able to join
- Residents of the United States or Canada
- MRI and/or CT scans showing unilateral stroke or stroke-like damage to primary visual cortex or its immediate afferent white matter sustained 1-year or more prior to enrollment
- Reliable visual field defects in both eyes as measured by Humphrey, Macular Integrity Assessment (MAIA), Goldmann, and/or equivalent perimetry. This deficit must be large enough to enclose a 5-deg diameter visual stimulus.
- Ability to fixate on visual targets reliably for 1000ms (as demonstrated by visual fields, and verified in study participation)
- Willing, able, and competent to provide informed consent
- Cognitively able to understand and respond to written and oral instructions in English
Who cannot join
- Past or present ocular disease interfering with visual acuity
- Corrected vision worse than 20/40 in either eye
- Presence of damage to the dorsal Lateral Geniculate Nucleus
- Diffuse, whole brain degenerative processes
- Brain damage deemed by study staff to potentially interfere with testing ability or outcome measures
- Documented history of traumatic brain injury
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- Documented history of drug/alcohol abuse
- Current use neuroactive
- Cognitive or seizure disorders
- Subjects with one-sided attentional neglect
About this study
The purpose of this study is to investigate how visual orientation discrimination and metacognition (i.e., perceptual confidence) are affected by occipital stroke that causes hemianopia and quadrantanopia in adults. This research will provide insight as to how the residual visual system, which not directly damaged by the occipital stroke, processes orientation (assayed in terms of orientation discrimination) and metacognition (by measuring perceptual confidence for orientation discrimination). These measures will be used to refine computational models that attempt to explain how the brain copes with loss of primary visual cortex (V1) as a result of stroke. This knowledge is essential to devise more effective visual rehabilitation therapies for patients suffering from occipital strokes.
- Conditions
- Vision Loss Partial, Vision; Loss, Both Eyes, Hemianopia, Homonymous, Hemianopia, Quadrantanopia, Stroke, Ischemic
- Keywords
- Occipital stroke, Vision loss after stroke, Vision recovery, Vision restoration, Partial vision loss, vision loss
- Medical subject headings
- Blindness, Hemianopsia, Ischemic Stroke, Blindness, Cortical, Vision Disorders
What is being measured
The primary outcome is the main question the study is designed to answer.
Orientation discrimination threshold
Assessment of Static Orientation Discrimination.
For each subject, the investigators will measure the ability to correctly identify the orientation of non-moving visual stimuli that vary in degree of angle tilt to the right or left of vertical. The investigators will measure the degree of angle tilt that can be reliably detected at a 72-75% correct level of performance. Tilt difference from vertical will vary between 80° (maximum) and 0.1° (minimum) based on subject performance and an adaptive staircase that will change tilt magnitude depending on subject performance, increasing the tilt (making the task easier) for each incorrect answers and decreasing tilt (making the task harder) after a number of correct answers in a row.
Measured: Baseline
Perceptual Confidence in Orientation Discrimination
Assessment of Metacognition (i.e., perceptual confidence) in Orientation Discrimination.
For each subject, the investigators will measure their confidence in identifying an object's tilt to the right or left of vertical. A running tally of 'response points' will be collected during the orientation testing. Points will be awarded for each response on a scale, with the highest points awarded for "correct discrimination \& high confidence", intermediate points awarded for "correct discrimination \& low confidence", followed by "incorrect discrimination \& low confidence" and with points subtracted for "incorrect discrimination \& high confidence". Total points will be recorded for each test, with the patient asked to accumulate the highest number of points they can during the task.
Measured: Baseline
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted8 Apr 2024
- Study startDec 2025 (estimated)
- Primary completionSep 2028 (estimated)
- Study completionSep 2029 (estimated)
Why it stopped: Study was never officially approved by IRB and never open to enrollment. Submission withdrawn due to lack of funding.
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Vision Loss PartialStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Case only
- Time perspective
- Cross-sectional
- Enrolment
- 0 participants (actual)
Sponsor and investigators
- Lead sponsor
- University of Rochester
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Krystel Huxlin, University of Rochester
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06352086
- Sponsor's protocol ID
- STUDY00009227
- Status last verified
- Oct 2024
- First submitted
- 1 Apr 2024
- Last updated
- 8 Oct 2024
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 8 Oct 2024. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Understanding Visual Processing After Occipital Stroke
- ClinicalTrials.gov ID
- NCT06352086
- Acronym / sponsor ID
- STUDY00009227
- Conditions
- Vision Loss Partial, Vision; Loss, Both Eyes, Hemianopia, Homonymous, Hemianopia, Quadrantanopia, Stroke, Ischemic
- Keywords
- Occipital stroke, Vision loss after stroke, Vision recovery, Vision restoration, Partial vision loss, vision loss
- Study type
- Observational
- Recruitment status
- WithdrawnReason stopped: Study was never officially approved by IRB and never open to enrollment. Submission withdrawn due to lack of funding.
- Enrolment
- 0 participants (actual)
- Lead sponsor
- University of RochesterUniversity, hospital or other
- Study start
- Dec 2025 (estimated)
- Primary completion
- Sep 2028 (estimated)
- Study completion
- Sep 2029 (estimated)
- First posted
- 8 Apr 2024 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The purpose of this study is to investigate how visual orientation discrimination and metacognition (i.e., perceptual confidence) are affected by occipital stroke that causes hemianopia and quadrantanopia in adults. This research will provide insight as to how the residual visual system, which not directly damaged by the occipital stroke, processes orientation (assayed in terms of orientation discrimination) and metacognition (by measuring perceptual confidence for orientation discrimination). These measures will be used to refine computational models that attempt to explain how the brain copes with loss of primary visual cortex (V1) as a result of stroke. This knowledge is essential to devise more effective visual rehabilitation therapies for patients suffering from occipital strokes.
Study design
- Observational model
- Case only
- Time perspective
- Cross-sectional
Who may qualify
- Ages
- 21 to 75 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Subjects will all be individuals who have sustained partial vision loss after an occipital lobe stroke.
Key inclusion criteria (6 listed)
- Residents of the United States or Canada
- MRI and/or CT scans showing unilateral stroke or stroke-like damage to primary visual cortex or its immediate afferent white matter sustained 1-year or more prior to enrollment
- Reliable visual field defects in both eyes as measured by Humphrey, Macular Integrity Assessment (MAIA), Goldmann, and/or equivalent perimetry. This deficit must be large enough to enclose a 5-deg diameter visual stimulus.
- Ability to fixate on visual targets reliably for 1000ms (as demonstrated by visual fields, and verified in study participation)
- Willing, able, and competent to provide informed consent
Key exclusion criteria (10 listed)
- Past or present ocular disease interfering with visual acuity
- Corrected vision worse than 20/40 in either eye
- Presence of damage to the dorsal Lateral Geniculate Nucleus
- Diffuse, whole brain degenerative processes
- Brain damage deemed by study staff to potentially interfere with testing ability or outcome measures
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
Orientation discrimination threshold
Time frame: Baseline
Assessment of Static Orientation Discrimination. For each subject, the investigators will measure the ability to correctly identify the orientation of non-moving visual stimuli that vary in degree of angle tilt to the right or left of vertical. The investigators will measure the degree of angle tilt that can be reliably detected at a 72-75% correct level of performance. Tilt difference from vertical will vary between 80° (maximum) and 0.1° (minimum) based on subject performance and an adaptive staircase that will change tilt magnitude depending on subject performance, increasing the tilt (making the task easier) for each incorrect answers and decreasing tilt (making the task harder) after a number of correct answers in a row.
Perceptual Confidence in Orientation Discrimination
Time frame: Baseline
Assessment of Metacognition (i.e., perceptual confidence) in Orientation Discrimination. For each subject, the investigators will measure their confidence in identifying an object's tilt to the right or left of vertical. A running tally of 'response points' will be collected during the orientation testing. Points will be awarded for each response on a scale, with the highest points awarded for "correct discrimination \& high confidence", intermediate points awarded for "correct discrimination \& low confidence", followed by "incorrect discrimination \& low confidence" and with points subtracted for "incorrect discrimination \& high confidence". Total points will be recorded for each test, with the patient asked to accumulate the highest number of points they can during the task.
Results and safety
The study was withdrawn before enrolling participants, so there are no results.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 8 Oct 2024.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
Questions about this trial
What is this clinical trial studying?
An observational study of Vision Loss Partial and Vision; Loss, Both Eyes, run by University of Rochester.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 6 inclusion and 10 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: withdrawn, as of the sponsor's last update on 8 Oct 2024. Status can change between updates, so confirm with the study contact before making plans.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study was withdrawn before enrolling participants, so there are no results.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Orientation discrimination threshold (time frame: Baseline). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 8 Oct 2024.