Changes in Tear Lipid Layer Thickness After Short Exposure to Light Emitting Diode Displays

August 5, 2021 updated by: National Cheng-Kung University Hospital

Video display terminals (VDTs) are ubiquitous, and engagement in digital screens has grown substantially across all age groups worldwide. Prolonged exposure to VDTs is associated with the development of various health problems. By now, it is unclear whether transient exposure to VDTs leads to ocular surface changes, especially regarding lipid layer thickness (LLT). This study aim to determine if short-term exposure to light-emitting diodes (LEDs) leads to ocular parameter changes.

This is a prospective, cross-sectional study. Patients were recruited at the National Cheng-Kung University Hospital, a tertiary referral center in southern Taiwan, for examination, including best-corrected visual acuity (BCVA), intraocular pressure (IOP), lipid layer thickness (LLT), and blink rates and patterns before and after watching an LED display for 15 minutes. The estimated result is that the LLT and blink rates will decrease after VDT watching.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

Video display terminals (VDTs) are ubiquitous, and engagement in digital screens has grown substantially across all age groups worldwide. During the coronavirus disease 2019 (COVID-19) pandemic, lockdowns and increasing demand for digital learning and working have led to more frequent and sustained VDT use. Prolonged exposure to VDTs is associated with the development of various health problems, including psychosocial issues, venous thromboembolism, fatigue, and visual complaints.

Computer vision syndrome (CVS) is one of the most frequently encountered problems among VDT users. CVS comprises several visual and musculoskeletal symptoms resulting from VDT use, such as eye strain, dryness and burning sensation of the eye, blurred vision, and neck and shoulder pain. A major alteration is the development of dry eye disease (DED), occurring in 60 % of those with CVS. Dry eye symptoms, corneal erosions, short tear-film breakup time (BUT), low tear meniscus height, and meibomian gland dysfunction (MGD) are all DED presentations encountered by VDT users. The continuous use of VDTs is an established risk factor for CVS and DED. However, it is unclear whether transient exposure to VDTs leads to ocular surface changes, especially regarding lipid layer thickness (LLT).

This study investigated if the short-term use of light-emitting diode (LED) displays (one type of VDT) changed the ocular parameters, including best-corrected visual acuity (BCVA), intraocular ocular pressure (IOP), the CVS-Questionnaire (CVS-Q) score, the blink rate, the partial blink ratio, and LLT. To our knowledge, this is the first study to focus on the immediate effects of LEDs on the eye.

This prospective clinical study was conducted in the Ophthalmology Department of the National Cheng Kung University Hospital (NCKUH), Tainan, Taiwan. The study was approved by the Institutional Review Board of NCKUH and followed the tenets of the Declaration of Helsinki. Written informed consent was obtained from all the participants.

The inclusion criteria were generally healthy individuals aged between 20 and 65 years who were willing to participate in the study. The exclusion criteria were ages below 20 or over 65 years, a BCVA score of <0.1 on the Landolt C chart in either eye, a BCVA difference of >0.2 between the eyes, and a history of ocular diseases or previous ocular surgery.

Participants were instructed to fill out a basic information form, including their name, sex, age, and contact information. They were also informed to avoid wearing contact lenses for two days before the test. The experiment was conducted on August 22, 2020. For the baseline test, the participants were asked to complete the CVS-Q to assess their CVS. Next was a series of ocular examinations, including BCVA, IOP, LLT, an optical coherence tomography (OCT) scan of the macula, and fundus autofluorescence (FAF) imaging. The LLT and blink rates were measured using the LipiView II Ocular Surface Interferometer following the standard protocol (TearScience, Morrisville, NC, USA). After the examination, the participants watched a short movie on an LED screen (InnoLux, Taiwan) for 15 minutes in a bright room. The viewing distance was approximately 1.5 meters. After the movie ended, the participants were instructed to complete the CVS-Q and undergo the BCVA, IOP, and LLT tests again. The baseline BCVA, IOP, OCT, and FAF images of each participant were reviewed by three NCKUH ophthalmologists to screen for clinically significant ocular pathology.

Statistical analyses were performed using R software version 4.1.0 (R Core Team, Vienna, Austria) and SAS Enterprise Guide (version 9.4; SAS Institute Inc., Cary, NC, USA). Paired t-tests were used to compare the BCVA, IOP, CVS-Q score, LLT, blink rate, and the partial blink ratio before and after watching the LED display. Statistical significance was set at P <0.05.

Study Type

Interventional

Enrollment (Actual)

60

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

  • Taiwan
      • Tainan, Taiwan
        • National Cheng Kung University 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

20 years to 65 years (Adult, Older Adult)

Accepts Healthy Volunteers

Yes

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • generally healthy individuals aged between 20 and 65 years who were willing to participate in the study

Exclusion Criteria:

  • ages below 20 or over 65 years
  • a BCVA score of <0.1 on the Landolt C chart in either eye
  • a BCVA difference of >0.2 between the eyes
  • a history of ocular diseases or previous ocular surgery

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: Other
  • Allocation: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: LED screen
Device: LED screen (InnoLux, Taiwan)
Participants watch a short movie on an LED screen (InnoLux, Taiwan) for 15 minutes in a bright room. The viewing distance was approximately 1.5 meters.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
Lipid Layer Thickness
Time Frame: Change from baseline lipid layer thickness at 15 minutes
Change from baseline lipid layer thickness at 15 minutes

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Visual Acuity
Time Frame: Change from baseline visual acuity at 15 minutes
Change from baseline visual acuity at 15 minutes
Intraocular Pressure
Time Frame: Change from baseline intraocular pressure at 15 minutes
Change from baseline intraocular pressure at 15 minutes
Blink rates
Time Frame: Change from baseline blink rates at 15 minutes
Change from baseline blink rates at 15 minutes
Computer Vision Syndrome Questionnaire Score
Time Frame: Change from Baseline Computer Vision Syndrome Questionnaire Score at 15 minutes
The Computer Vision Syndrome Questionnaire is a validated questionnaire to assess the severity of the computer vision syndrome.
Change from Baseline Computer Vision Syndrome Questionnaire Score at 15 minutes

Collaborators and Investigators

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

Sponsor

National Cheng-Kung University Hospital

Collaborators

Ministry of Science and Technology, Taiwan

Investigators

  • Study Chair: Yi-Hsun Huang, PhD, National Cheng-Kung University Hospital

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)

July 1, 2020

Primary Completion (Actual)

August 22, 2020

Study Completion (Actual)

August 22, 2020

Study Registration Dates

First Submitted

July 29, 2021

First Submitted That Met QC Criteria

August 5, 2021

First Posted (Actual)

August 12, 2021

Study Record Updates

Last Update Posted (Actual)

August 12, 2021

Last Update Submitted That Met QC Criteria

August 5, 2021

Last Verified

July 1, 2021

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • A-ER-108-489

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

The informed consent of this study specified that the participants' data would only be used in this study

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 Dry Eye Disease

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Hong Kong

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Subscribe