The Effect of Varying Brightness on Palpebral Aperture

January 14, 2022 updated by: University of Edinburgh

The Effect of Varying Brightness Levels on Palpebral Aperture and the Point of Orbicularis Engagement Using EEG Signalling.

We aim to establish the point at which glare from bright lights begins to engage our eyelids - causing us to "squint". We will be using a video camera with an LED ring light around it facing the volunteer and we will record the eyelid position as the light brightness is increased gradually. Many studies have looked at the effect glare has on a person through qualitative questionnaires but few have been able to quantify this.

Study Overview

Status

Active, not recruiting

Conditions

Intervention / Treatment

Detailed Description

Our study will aim to establish the point of orbicularis engagement based on luminous intensity Murray et al. created an Ocular Stress Monitor to see if the contracture of the muscles on the eyelid indicative of pain as a light source was increased in luminosity 8 Our study will go one step further by using video technology and a portable EEG machine to detect the pulses of lid contracture as luminosity of a ring light i s increased incrementally. An advanced calibrated datalogging LED light meter will simultaneously record the level of brightness to establish at which point the spike in EEG occurs. Screenshots from the video recording will be taken and accurate MRD1 measurements can be taken at the point of orbicular i s engagement.

The scientific justification for this research question is twofold We wish to establish the threshold at which orbicularis engages such that palpebral aperture and MRD measurements are altered. This is relevant to the technique of taking these measurements in the clinical environment and the light intensity at which these measurements are taken. We wish to establish the light intensity which should not be exceeded to take these measurements. As photography becomes increasingly used in oculoplastic s clinics we envisage palpebral aperture and MRD1 measurements being performed digitally rather than manually These measurements are relevant to pre operative and post operative imaging, and surgical planning. Furthermore, our results maybe applicable more widely to industry, for example vehicle headlights, bicycle lights, camera flash, workplace lighting.

Reference: Murray I, Plainis S, Carden D. The ocular stress monitor: a new device for measuring discomfort glare. Lighting Research Technology. 2002;34(3):231 239.

Study Type

Interventional

Enrollment (Anticipated)

40

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United Kingdom
      • London, United Kingdom, NW3 2QY
        • Ophthalmology, Royal Free Hospital

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 65 years (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Aged between 18 and 65 years of age
  • A member of the Royal Free NHS trust

Exclusion Criteria:

  • No known ocular pathology
  • No lid problems/ptosis or previous lid surgery
  • No contact lenses in for duration of experiment
  • No pseudophakia
  • No neurological disease

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Basic Science
  • Allocation: Non-Randomized
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: The observation of eyelid positioning and EEG pulses from the eyelid on increasing brightness
In a dimly lit room the participant will place their chin on the slit lamp We will use t he optimal background illumination used for Humphrey and Goldman visual fields which is 31.5 apostilbs (10Lux 9 They will look into the video camera placed 50cm away, which will have a dimmable remote control ring light fitted around it. The part icipant will have a reference measure taped to the headrest and three electrodes placed around the right eye. One active electrode place on the lower lid and one reference electrode towards the temporal margin and one earth electrode placed on the forehead The brightness of the ring light will be increased via the dimmer switch whilst simultaneously recording the lux with the LED light meter. The participant will be advised t o close their eyes if the brightness becomes uncomfortable and this will be repea ted three times.
Other: Review of eyelid positioning in increasing brightness levels
Up to 30 seconds, three times, looking into a video camera as glare is incrementally increased.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
The point at which the eyelid begins to contract under what brightness level
Time Frame: All carried out within a 2 week period
Using a light meter, ring light, and EEG machine
All carried out within a 2 week period

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

University of Edinburgh

Collaborators

Royal Free Hospital NHS Foundation Trust
National Health Service, United Kingdom

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

January 14, 2022

Primary Completion (Anticipated)

February 21, 2022

Study Completion (Anticipated)

February 21, 2022

Study Registration Dates

First Submitted

January 14, 2022

First Submitted That Met QC Criteria

January 14, 2022

First Posted (Actual)

January 27, 2022

Study Record Updates

Last Update Posted (Actual)

January 27, 2022

Last Update Submitted That Met QC Criteria

January 14, 2022

Last Verified

January 1, 2022

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 1062/RD

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

Undecided

IPD Plan Description

Data findings will be presented to the department, all those involved at the next departmental meeting.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Eyelid Ptoses

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Bulgaria

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

3
Subscribe