The increased use of digital devices such as computers, smart-phones, tablets, and laptops has transformed how people learn and work and has increased the use of screens. This has created visual challenges for some users, such as maintaining a clear vision for a long period even when looking at different devices. Consequently, digital device users can experience eye problems such as blurred vision, eye strain, headaches, and dry eyes. Such problems are more common in people aged 21-45, and it seems that the COVID-19 pandemic has worsened them.

Studies suggest that using specially designed lenses could reduce these problems. Therefore, the investigators aim to study whether specially designed lenses are more effective than standard ones in minimising these problems. The study will be conducted at the University of Central Lancashire at the Preston campus (UK). The study will recruit 300 participants, divided into two equal groups. Participants in group A will receive spectacles with special lenses while group B will receive spectacles with standard lenses. All Participants will be assessed three times, at 4-week intervals, and the final analysis will be performed at 14 weeks. The reduction of the eye problems will be assessed using a validated questionnaire which will produce a score that will be compared between the two groups at the end of the study.

The study's potential benefits are twofold:

1. Patients using the new lenses will hopefully see a reduction in eye problems
2. Opticians will provide be able to provide better patient care.

Background What is the problem to be addressed? In the last two decades, the way people acquire information has changed dramatically. During that time, engagement with digital devices in developed countries has increased significantly, particularly in the field of mobile media. The increasing use of digital devices showed implications for health, eyes, and vision. A European study found out that by the age of 3, 68% of children regularly use a computer and 54% undertake online activities. In 2016, it was estimated that UK adults typically spend almost 5 hours a day using digital media, with a similar pattern developing in the USA.

The use of digital devices has caused Computer Vision Syndrome (CVS), also called Digital Eye Strain (DES) or Visual Fatigue (VF), which has been well described in the literature for over 20 years.

What is Computer Vision Syndrome? The American Optometric Association defines Computer Vision Syndrome (CVS) as a group of eye and vision-related problems resulting from prolonged exposure to digital/computer devices. CVS has been linked to using a variety of digital devices such as computer/laptop screens, tablets, and smart-phones, which has been steadily growing. The most common symptoms are eye strain, tired eyes, irritation, burning sensation, redness, blurred vision, and double vision. Therefore, a person using digital devices and complaining about one or more of those symptoms might be suffering from CVS. Furthermore, CVS could cause non-ocular symptoms such as headaches and pain in the shoulders, neck, and/or back. Research has identified four CVS categories. The first is asthenopia: eye strain, tired eyes, and dry eyes. The second is ocular and related to eye surface: watery eyes, irritated eyes, contact lens problems. The third is the visual category: blurred vision and slowness of focus. The fourth category is extraocular and is represented by neck, shoulder, and back pain.

CVS symptoms result in poorer visual performance, and even though they are transient, they occur frequently and cause considerable discomfort for sufferers. CVS lowers productivity (increased errors and more frequent breaks) and impinges on job satisfaction and quality of life. Millions of individuals of all ages are at risk of CVS, and according to different studies, the prevalence of CVS ranges from 25% to 93%, depending on the cohort of the studied population, the definition and methodology employed to measure CVS. These results indicate that a large proportion of the population may need treatment for CVS.

CVS affects all age groups, including older age groups (aged 65+), in which the use of technology is also rapidly growing. However, the most affected population are younger users, who are more likely to simultaneously use two or more digital devices. For example, recent US data indicates that while adults aged 60 years and over prefer using laptops and desktop computers, younger adults are more likely to use smart-phones too. Since they use digital devices for work and social purposes (e.g. social media), they often multitask and switch between different devices.

The COVID-19 pandemic introduced homeworking and remote learning and further increased exposure to digital screens. Moreover, lockdown increased unhealthy digital recreational activities, with people turning to television and social media for entertainment.

Management of Computer Vision Syndrome CVS management includes correction of refractive error and/or presbyopia (long-sightedness caused by loss of elasticity of the lens of the eye, occurring typically in middle and old age; managed by prescribing a 'near add'), dry eye management, regular screen breaks, and eye exercises for vergence and accommodative problems (such as a lag in changing the focus from near to far distance). Some studies have explored the role of blue light-filtering spectacle lenses with mixed results, indicating that blue light-filters may not alleviate symptoms of CVS. Given the high prevalence of CVS and near-universal use of digital devices, it is essential that eye care practitioners can provide advice and management options that are evidence based.

Aim To evaluate the effectiveness of the Super Enhanced Single Vision Lens 01 (SESL01) in reducing symptoms of Computer Vision Syndrome.

Inclusion Criteria:

• Able to provide informed consent

• 21-45 years of age

• Adults diagnosed with CVS: CSV-Q score ≥6

• Participants WITH AND WITHOUT refractive error are acceptable BUT none should have previously worn a "near add" correction (e.g. no previous bifocal/varifocal/enhanced single vision lens [ESL] wear)

• Range of refractive errors should be no more than +4.00 to -6.00 dioptric spherical power (DS) and +2.00 dioptric cylindrical power (DC)

• Must use digital devices for work and/or leisure for at least 1 hour per day (this includes smart-phones, tablets, and laptops but EXCLUDES those using desktop computers only)

• Patients MUST have visual symptoms associated with digital device use, e.g. one or more of the following symptoms:

  • Tired eyes
  • Eye strain
  • Blurred vision
  • Frontal headaches
  • Difficulties keeping clear vision when changing focus from near to distance
  • Difficulties keeping clear vision when changing focus from one device to another

Exclusion Criteria:

• Lack of capacity to provide informed consent.

• Amblyopia

• Pregnancy

• Diagnosed dry eye disease

  o If a patient develops dry eye symptoms or is diagnosed at follow-up appointments, treatment will be started and assessed in two weeks.

• On anti-depressants (or other medication that can affect accommodation, such as reduced focusing power)

• Any diagnosed ocular pathology (such as glaucoma, corneal dystrophies, lid disorders, and retinal pathologies)

• Change in ±0.75DS/DC in the spectacle prescription

Individual participant data will not be shared with other researchers.

The procedure adopted in this study for assuring the allocation concealment will be the use of sequentially numbered, opaque, and sealed envelopes (SNOSE).

Blinding : In our study, the clinicians (opticians) performing the assessment and follow-up and the patients receiving and wearing the spectacles will be blinded to the treatment.