Where next for contact lens research?

This editorial fronts the second virtual issue for Optometry & Vision Science. Virtual issues are a collection of papers from previously published issues of the journal that are brought together in a single, online publication. They highlight the important contribution the journal has made in supporting myopia research.

Moderate-severe peripheral neuropathy in diabetes associated with an increased risk of dry eye disease.

Significance: This study establishes an increased risk of developing dry eye disease (DED) in patients with diabetic peripheral neuropathy using validated diagnostic criteria for both conditions.

Purpose: The disruption of ocular surface homeostasis has been associated with diabetes. However, it remains unclear if this association is independently influenced by peripheral neuropathy secondary to diabetes.

Meibomian Gland Shortening Is Associated With Altered Meibum Composition.

Purpose: The purpose of this study was to investigate differences in the composition of meibum extracted from human meibomian glands displaying different morphological characteristics.

Methods: Adult participants with evidence of meibomian gland shortening were enrolled. Glands were observed using infrared meibography, and meibum was collected from one short and one long gland from the lower eyelid of the same eye.

Tear film hTERT and corneal nerve characteristics in dry eye disease.

Clinical Relevance: The behaviour of human telomerase reverse transcriptase (hTERT) in tears reflects its role in maintaining the ocular surface homoeostasis, as it is increased after the initial fitting of contact lenses and post-overnight lid closure.

Background: hTERT has been shown to respond to cellular stress in neurodegenerative diseases and to enhance axonal regeneration after peripheral axotomy in an animal model. This work investigated whether the behaviour of hTERT in the tear film reflects ocular surface inflammation and neuronal changes in the presence of dry eye disease.

BCLA CLEAR Presbyopia: Management with contact lenses and spectacles.

This paper seeks to outline the history, market situation, clinical management and product performance related to the correction of presbyopia with both contact lenses and spectacles. The history of the development of various optical forms of presbyopic correction are reviewed, and an overview is presented of the current market status of contact lenses and spectacles. Clinical considerations in the fitting and aftercare of presbyopic contact lens and spectacle lens wearers are presented, with general recommendations for best practice.

2023 Prentice Medal Award lecture: Ocular surface-related symptoms of discomfort and other stories.

I have been fortunate to spend portions of my career in each of private practice, industry, and academia. At some times, these occupations have dictated the research direction, whereas, at others, curiosity has been allowed to dominate. This has resulted in multiple avenues of inquiry (some might say, too many), along which I have traveled with a rich and varied cast of collaborators, who have all taught me a great deal.

Behaviour of hTERT in the tears of neophyte contact lens wearers during the sleep/wake cycle.

Purpose: To investigate the behaviour of telomerase reverse transcriptase (hTERT) in the tears of healthy neophyte contact lenses-wearing individuals during the sleep/wake cycle. A subsequent aim was to investigate whether hTERT behaviour was associated with inflammatory mediators interleukin-6 (IL-6) and tumour necrosis factor-alpha (TNF-α) in tears.

Methods: Flush tears were collected from 19 healthy, non-contact lens-wearing participants (11 males, 8 females, mean age 31.

Diagnosing dry-eye: Which tests are most accurate?

Purpose: To demonstrate how the likelihood of making a correct diagnosis of dry eye disease varies according to the clinical test methods used.

Methods: The probability of a person having dry eye, given that they return a positive test, was calculated for a range of standard tests, using the Bayes-Price rule. Global specificity and sensitivity values for each test were estimated by employing the Beta distribution to combine all relevant data obtained from a literature review.

Comparison of vision performance of spectacles prescribed to 0.05D versus 0.25D steps.

Clinical Relevance: Traditionally, refraction is performed, and spectacles are manufactured in in 0.25D-steps. Trial and spectacle lenses manufactured in smaller increments may allow for a more accurate refraction and prescribed spectacles.

The Impact of Probiotics and Prebiotics on Dry Eye Disease Signs and Symptoms.

Dry eye is considered an inflammatory disease. Gut microbiota are important in the regulation of low-grade chronic inflammation, including in the eye. Probiotics and prebiotics are increasingly used to regulate chronic-disease-associated gut dysbiosis.

Diurnal Variation of Corneal Dendritic Cell Density.

To measure variation in corneal dendritic cell density, and percentage of mature to total dendritic cells, in healthy individuals during the sleep/wake cycle. Using confocal microscopy, images of the subbasal nerve plexus were captured from 19 healthy, noncontact lens wearing participants. The central cornea and inferior whorl were imaged three times (midday, before sleep, upon awakening).

The role of retinotopic cues in deciphering the direction and magnitude of monocular dynamic ocular accommodation: A review.

Accommodative responses of humans operate seamlessly to ensure clear vision of targets at different viewing distances, up until the onset of presbyopia. To achieve this, the visual system must correctly decipher the polarity and magnitude of retinal defocus in real-time, and often under very challenging viewing conditions. The past seven decades of research in this area has identified several retinotopic cues that may potentially provide the desired odd- and even-error information to the visual system for solving these challenges.

Review of 20 years of soft contact lens wearer ocular physiology data.

Background: Since the introduction of Silicone hydrogel (SiHy) contact lenses 20 years ago, industry has continued to modify lens materials, designs, lens care products and manufacturing processes, striving to improve contact lens physiological performance, comfort, and convenience for wearers. The purpose of this study was to investigate whether the ocular health of habitual soft contact lens wearers today is better than it was in previous decades.

Methods: Baseline ocular physiology data for 3624 participants from a The Brien Holden Vision Institute clinical trials database were retrospectively reviewed.

Associations between Binocular Vision Disorders and Contact Lens Dissatisfaction.

Significance: These data demonstrate that binocular vision disorders (BVDs) contribute to contact lens (CL) dissatisfaction independently of CL discomfort (CLD) in myopic, pre-presbyopic, adult, single-vision CL wearers.

Purpose: This study aimed to determine whether BVDs contribute to CL dissatisfaction and whether this contribution is independent of CLD.

Methods: Participants attended one clinical visit while wearing their habitual CLs.

The validity of point of care tear film osmometers in the diagnosis of dry eye.

Purpose: To determine the repeatability of TearLab and I-PEN osmometers in vivo and their accuracy in vitro.

Design: Prospective, single-visit study.

Methods: The tear osmolarity of 28 participants was evaluated with TearLab and I-PEN on two occasions in random order, over a 2-h period.

Bio-chemical markers of chronic, non-infectious disease in the human tear film.

The tear film is a thin, moist layer covering the ocular surface and is laden with proteins, peptides, lipids, mucins, electrolytes and cellular debris which function to maintain the healthy status of the ocular surface. In many cases of ocular or systemic disease, the integrity of this layer is changed and/or the balance of its constituents is disturbed. Since tears are easy and quick to collect and can be stored for long periods, they have the potential to be a valuable source of information relevant to many disease states.

The global prevalence of dry eye disease: A Bayesian view.

Purpose: To provide estimates for the prevalence of dry eye disease globally and in sub-groups defined by: diagnostic criterion, sex, geographic location and age, using a Bayesian approach.

Methods: Modelling prevalence as a Beta distribution, estimates were inferred from Bayesian posterior distributions obtained by combing an uninformed prior with likelihood functions generated from all relevant studies reporting dry eye prevalence between 1997 and 2021.

Results: Global prevalence of dry eye disease was estimated at 11.

Filaggrin Expression in the Lid Margin During Contact Lens Wear.

Aim: To investigate the expression of the keratinization-related protein, filaggrin, in the lid margin epithelium of contact lens (CL) wearers compared with nonwearers.

Methods: This was a cross-sectional study of 100 individuals with different exposures to CL wear: short, moderate, and long experience; previous CL wearers; and nonwearers as controls. Impression cytology samples were collected from the lid wiper (LW) area of the central upper lid margin.

Photobiomodulation (low-level light therapy) and dry eye disease.

Dry eye disease is one of the most common, chief-complaints presenting in clinical practice, with a prevalence of up to 50%. Evaporative dry eye, as a result of meibomian gland dysfunction, is thought to be the biggest component factor. Treatments for meibomian gland dysfunction aim to restore tear film homoeostasis and include warm compress therapy, eyelid hygiene, in-office meibomian gland expression and lipid-containing, artificial tears.

Temporal considerations in contact lens discomfort.

Purpose: To determine the relative contributions to perceived discomfort during contact lens wear of contact time with the lens and the time of day at which wear begins, using a wearing framework similar to that of regular users.

Methods: Twenty-three participants reported ocular discomfort using a 1-100 visual analogue rating scale, when prompted by email, during one day without contact lenses and on three other days while wearing soft contact lenses for twelve hours. Contact lens wear began at a different time on each day.

Changes in the tarsal conjunctiva viewed by in vivo confocal microscopy are associated with ocular symptoms and contact lens wear.

Purpose: To investigate the effect of soft contact lens (CL) wear on the morphology of the epithelial-lamina propria junction as well as the possible association with symptoms of discomfort.

Methods: Ninety-two subjects were recruited, including 60 soft CL wearers, 16 previous wearers, and 16 non-wearers. Additionally, subjects were classified as symptomatic or asymptomatic using the Contact Lens Dry Eye Questionnaire 8 for the CL wearers (a score ≥ 12 was considered symptomatic) and the Dry Eye Questionnaire 5 for the previous wearers and non-wearers (a score ≥ 5 was considered symptomatic).

The relationship between tear film MMP-9 and meibomian gland changes during soft contact lens wear.

Purpose: To investigate the association between levels of MMP-9, a common marker of inflammation in tears, and changes to the meibomian glands accompanying soft contact lens (CL) wear.

Methods: Flush tears were collected from: (1) three groups of CL wearers who had worn CLs on a daily basis for different durations (Short: 2 ± 1 years, Moderate: 5 ± 1 years and Long experience: 10 ± 2 years); (2) a group of previous CL wearers (PWs) who had ceased wear for at least 6 months; and (3) healthy non-wearers (NW) as a control group. Total MMP-9 and its inhibitor, tissue inhibitor of MMPs-1 (TIMP-1) concentration were established using sandwich enzyme-linked immunosorbent assay.