Polarization Perception in Health and Disease. Testing a New Sight Test

NCT ID: NCT03823092

Last Updated: 2019-01-30

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.

Recruitment Status

UNKNOWN

Total Enrollment

300 participants

Study Classification

OBSERVATIONAL

Study Start Date

2017-11-09

Study Completion Date

2019-07-31

Brief Summary

Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.

A study to assess the utility of human polarization pattern perception for the detection, diagnosis and monitoring of eye disease

Detailed Description

Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.

The recently described high sensitivity of the human eye to differentiate small angular differences in linear polarization and evidence supporting its macular origin (Misson, Anderson; 2017) suggests that human polarization sensitivity might be a useful diagnostic tool for macular disease. This augments a previous study in which we demonstrated the ability of the human visual system to detect isochromatic isoluminant polarization modulated pattern stimuli (Misson et al 2015).

This is an exploratory 'proof-of-concept' study to determine the clinical value of polarization pattern perception, PPP, in health and disease. We further propose that PPP might be valuable for the diagnosis, monitoring and early detection of macular disease. The latter includes common blinding conditions such as age related macular degeneration and diabetic retinopathy. It is also intended to investigate the effect of cataracts and cataract surgery on PPP: cataract surgery modifies the optics of the eye so might also modify PPP.

PPP is measured using a modification of the methodology described in (Misson et al 2015) and (Misson, Anderson; 2017) whereby polarization modulated patterns are presented on a modified LCD display. The observer's task is to report if they see an image and to describe the image. Images comprise simple patterns or traditional optotypes. A standard set of images are presented in pseudorandom order and the response recorded. A total score, the polarization pattern perception score PPP is then determined from the number of images seen/identified. A more refined metric, the polarization visual acuity pVA, will be derived from the response to the optotype stimuli. These data are then compared to conventional tests of visual structure and function including logMAR visual acuity, ocular examination and OCT scan data.

The study in anticipated to comprise:

Phase 1. Normative Evaluation: observational prospective cross-sectional.. A preliminary normative study will be undertaken on staff members. The aim is to quantify normative values in preparation for the clinical studies.

Hypotheses to be tested:

1. that healthy subjects can perceive polarization stimuli
2. that there is a threshold of polarization image resolution (pVA) analogous to visual acuity. Normative PPP and pVA data will be collected.

Phase 2 Patient Group: observational Prospective cross-sectional / case-control.

Phase 2 subjects will comprise normals and patients with cataracts/pseudophakia and/or AMD, other macular pathology, diabetic retinopathy..

The aim of this phase is to determine the effect, if any, of particular eye conditions on pVA/PPP alone and in comparison with other test parameters.

Hypotheses to be tested:

1. that eye conditions affect pVA/PPP
2. that specific eye conditions have a selective effect on pVA/PPP
3. that pseudophakia affects pVA/PPP

Phase 3: Cataract pre-op v post op pVA/PPP: prospective interventional case-control.

Timescale:concurrent with Phase 2 A subset of the phase 2 cataract patients will undergo cataract surgery according to clinical need. These patients are routinely reviewed 4 - 8 weeks post-op when the opportunity will arise to repeat pVA/PPP measurement. The fellow eye will serve as a control / provide data for repeatability assessment.

The aims of this phase are

1. to determine the repeatability of pVA/PPP testing in a heterogeneous patient group
2. to determine the effect of cataract surgery on the pre-operative pVA/PPP results
3. to determine if pVA/PPP is a useful determinant of post-operative visual outcome.

Hypotheses:

1. that pVA/PPP testing is repeatable
2. that there is a difference in pVA/PPP pre and post cataract surgery

Conditions

See the medical conditions and disease areas that this research is targeting or investigating.

Cataract Age Related Macular Degeneration Pseudophakia Macular Disease Diabetic Retinopathy Retinal Disease

Study Design

Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.

Observational Model Type

CASE_CONTROL

Study Time Perspective

CROSS_SECTIONAL

Study Groups

Review each arm or cohort in the study, along with the interventions and objectives associated with them.

Normal

phakic participants with no evidence of eye disorders

polarization sensitivity

Intervention Type DIAGNOSTIC_TEST

test of polarization vision as described in Study Description

Cataract

participants with cataract

polarization sensitivity

Intervention Type DIAGNOSTIC_TEST

test of polarization vision as described in Study Description

AMD

participants with age related macular degeneration

polarization sensitivity

Intervention Type DIAGNOSTIC_TEST

test of polarization vision as described in Study Description

Pseudophakic

particpiants who have had cataract surgery with intraocular lens implant

polarization sensitivity

Intervention Type DIAGNOSTIC_TEST

test of polarization vision as described in Study Description

other macula

participants with macular ddisorders other than AMD

polarization sensitivity

Intervention Type DIAGNOSTIC_TEST

test of polarization vision as described in Study Description

DR

participants with diabetic retinopathy

polarization sensitivity

Intervention Type DIAGNOSTIC_TEST

test of polarization vision as described in Study Description

Interventions

Learn about the drugs, procedures, or behavioral strategies being tested and how they are applied within this trial.

polarization sensitivity

test of polarization vision as described in Study Description

Intervention Type DIAGNOSTIC_TEST

Eligibility Criteria

Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.

Inclusion Criteria

\- willing and able to provide informed consent

Exclusion Criteria

* unwilling or unable to provide informed consent
* individuals wishing to exit the study
Minimum Eligible Age

18 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

Yes

Sponsors

Meet the organizations funding or collaborating on the study and learn about their roles.

Aston University

OTHER

Sponsor Role collaborator

South Warwickshire NHS Foundation Trust

OTHER

Sponsor Role lead

Responsible Party

Identify the individual or organization who holds primary responsibility for the study information submitted to regulators.

Gary Misson

Consultant ophthalmologist

Responsibility Role PRINCIPAL_INVESTIGATOR

Locations

Explore where the study is taking place and check the recruitment status at each participating site.

South Warwickshire NHS Foundation Trust

Warwick, Warwickshire, United Kingdom

Site Status RECRUITING

Countries

Review the countries where the study has at least one active or historical site.

United Kingdom

Central Contacts

Reach out to these primary contacts for questions about participation or study logistics.

Gary P Misson, PhD FRCOphth

Role: CONTACT

+44 01926495321

Jo Williams

Role: CONTACT

+44 01926495321

Facility Contacts

Find local site contact details for specific facilities participating in the trial.

Gary P Misson, PhD FRCOphth

Role: primary

+44 01926495321

Jo Williams

Role: backup

+44 01926495321

References

Explore related publications, articles, or registry entries linked to this study.

Misson GP, Timmerman BH, Bryanston-Cross PJ. Human perception of visual stimuli modulated by direction of linear polarization. Vision Res. 2015 Oct;115(Pt A):48-57. doi: 10.1016/j.visres.2015.08.004. Epub 2015 Aug 28.

Reference Type RESULT
PMID: 26291073 (View on PubMed)

Misson GP, Anderson SJ. The spectral, spatial and contrast sensitivity of human polarization pattern perception. Sci Rep. 2017 Nov 29;7(1):16571. doi: 10.1038/s41598-017-16873-6.

Reference Type RESULT
PMID: 29185499 (View on PubMed)

Other Identifiers

Review additional registry numbers or institutional identifiers associated with this trial.

17/WA/0180

Identifier Type: -

Identifier Source: org_study_id

More Related Trials

Additional clinical trials that may be relevant based on similarity analysis.

Retinal Investigation Using Optos OCT Device
NCT06846151 NOT_YET_RECRUITING NA
Retinal Imaging Using NOTAL-OCT
NCT03374020 COMPLETED
Dual Wavelength OCT
NCT03843840 COMPLETED