CLINICAL RELEVANCE: Vitamin B12 deficiency can affect macular and choroidal vasculature. Optical coherence tomography angiography (OCTA) and enhanced depth imaging OCT (EDI-OCT) are essential for early detection and moni...CLINICAL RELEVANCE: Vitamin B12 deficiency can affect macular and choroidal vasculature. Optical coherence tomography angiography (OCTA) and enhanced depth imaging OCT (EDI-OCT) are essential for early detection and monitoring of these microvascular changes, helping to prevent potential visual impairment. BACKGROUND: This study aimed to assess the impact of vitamin B12 deficiency on the vascular structures of the macula and choroid by using OCTA and EDI-OCT. METHODS: This prospective cross-sectional study included 34 individuals with vitamin B12 deficiency and 36 healthy participants as the control group. Macular vascular parameters, including superficial capillary plexus (SCP) and deep capillary plexus (DCP) vascular densities, and foveal avascular zone (FAZ) metrics, were measured using OCTA. The choroidal structure was assessed using EDI-OCT to calculate the total choroidal area (TCA), luminal area (LA), stromal area (SA), and choroidal vascularity index (CVI). RESULTS: Compared with the control group, patients with vitamin B12 deficiency showed significantly higher vascular densities in the SCP of the parafoveal superior quadrant, as well as in the DCP of the parafoveal superior hemi and superior quadrants ( = 0.03, = 0.04, and = 0.01, respectively). The remaining OCTA parameters did not exhibit any statistically significant variation between the groups. Choroidal assessment showed notable decreases in TCA, LA, SA, and central subfoveal choroidal thickness. Moreover, patients with vitamin B12 deficiency showed a significant increase in the CVI (all ≤ 0.01). CONCLUSION: Vitamin B12 deficiency is associated with complex alterations in macular and choroidal vascularity, including localised increased macular capillary densities and a paradoxical increase in the CVI despite decreased choroidal thickness.
CLINICAL RELEVANCE: Exposure to unregulated online content may impact health beliefs. Optometrists should be aware of these digital influences and incorporate targeted education strategies to promote eyecare practices. B...CLINICAL RELEVANCE: Exposure to unregulated online content may impact health beliefs. Optometrists should be aware of these digital influences and incorporate targeted education strategies to promote eyecare practices. BACKGROUND: This study investigates the effect of user-generated YouTube content on knowledge and beliefs in safe lens practices, and addresses growing concerns about the quality of unmoderated online health information and its potential impact on lens usage behaviours. METHODS: Using a pre-post experimental design, contact lens wearers viewed selected YouTube videos about lens care. Participants were randomised to watch videos containing evidence-based contact lens advice, poor advice, or a control video. Measurements of knowledge and beliefs in the importance of contact lens care practices were assessed using questionnaires before and after video viewing. RESULTS: A total of 154 contact lens wearers who were university students living in Australia participated in the study. Pairwise pre-post comparisons revealed better knowledge in the correct information group (62 vs 74%, = 0.01) with improved case and lens hygiene knowledge. Belief scores improved (68 vs 73%, = 0.005) and this was driven by case hygiene domain (80 vs 91%, < 0.001). There were no between-group differences for overall belief score, however case hygiene belief domain was higher in the correct video (91%) compared to the incorrect (81%, = 0.001) and control (81%, = 0.002) groups. After adjusting for co-variates, viewing the correct video remained predictive of beliefs. Lens wearing experience and better self-reported hygiene practices were associated with better knowledge and beliefs. CONCLUSION: Viewing of videos with correct information increased belief in the importance of contact lens care, particularly case hygiene, while evidence for impact on knowledge was mixed. Contact lens prescribers need to be aware that successful interventions to improve contact lens care practices may be improved by video viewing but should also include active behavioural modification strategies.
CLINICAL RELEVANCE: Early diagnosis, close monitoring, and timely intervention in patients with unilateral primary angle closure disease is necessary to prevent visual loss due to glaucoma. BACKGROUND: The aim of this st...CLINICAL RELEVANCE: Early diagnosis, close monitoring, and timely intervention in patients with unilateral primary angle closure disease is necessary to prevent visual loss due to glaucoma. BACKGROUND: The aim of this study is to investigate the biometric parameters of eyes in patients with asymmetric primary angle closure disease and to determine the biometric differences that can predispose to Primary Angle Closure Glaucoma (PACG). METHODS: This cross-sectional study included 224 eyes of 112 patients. Eyes with PACG were grouped as group A1 and fellow eyes of the same patient with either primary angle closure suspect or primary angle closure were grouped as group A2. Controls included healthy age and sex-matched patients with no evidence of glaucoma. These patients underwent clinical and ocular biometric measurements, including axial length, anterior chamber depth, lens thickness, and keratometry. Lens axial factor and relative lens position were calculated from the above ocular parameters. The differences in ocular biometric parameters between the cases and controls were compared and analysed. RESULTS: There was a significant difference in the mean anterior chamber depth between the cases. Relative lens position was found to be anterior in group A1 (0.220 ± 0.012) as compared to group A2 (0.223 ± 0.013), which was statistically significant ( = 0.002). There was no statistically significant difference in the mean axial length, mean lens thickness or mean lens axial factor in cases or controls. CONCLUSION: In a patient with primary angle closure disease, a relative anterior placement of the crystalline lens may predispose the eye to earlier occurrence of glaucomatous damage.
CLINICAL RELEVANCE: Integrating axial and anterior-segment measures, along with quadratic prediction and odds-based models, can support diagnosis, risk stratification, and management. BACKGROUND: The aim of this work is...CLINICAL RELEVANCE: Integrating axial and anterior-segment measures, along with quadratic prediction and odds-based models, can support diagnosis, risk stratification, and management. BACKGROUND: The aim of this work is to quantify the axial length (AL) - spherical equivalent (SE) relationship in Iraqi adults, assess sex differences within refractive categories, and develop prediction and risk models. METHODS: Cross-sectional study of 2,948 eyes (18-33 years) at a university eye-care clinic (Feb - May 2025). SE was measured by non-cycloplegic autorefraction (Nidek ARK-1) and AL by SS-OCT biometry (ZEISS IOL-Master 700). Refractive groups were emmetropia (-0.50 D < SE ≤ +0.50 D), mild myopia (-0.50 to -3.00 D), and moderate myopia (-3.25 to -6.00 D). Group differences were analysed with t-tests/ANOVA. Sex-stratified, within-category SE was examined with equivalence testing (TOST; ±0.25 D). Ordinary least-squares models predicted AL from SE and SE, and SE from AL and AL, adjusting for age and sex. Logistic regression mapped AL to odds of any myopia versus emmetropia and of moderate versus emmetropia plus mild; discrimination was evaluated by the ROC/AUC. RESULTS: Mean SE was +0.11 ± 0.29 D in emmetropia and -3.25 ± 1.67 D in myopia; mean AL 23.33 ± 0.60 mm and 26.03 ± 1.17 mm, respectively. AL differed across categories ( < 0.001). Females had longer AL within emmetropia (≈0.57 mm) and within mild - moderate myopia (≈0.70 mm; both < 0.001), while SE was equivalent by TOST. The AL - SE association was range dependent: strong and negative in emmetropia/mild myopia (R ≈ 0.83) and weaker in moderate myopia (R ≈ 0.45). Quadratic models improved prediction (adjusted R ≈ 0.936 for AL; ≈ 0.934 for SE; RMSE 0.42 mm and 0.54 D). Longer AL significantly increased the odds of myopia after adjustment. CONCLUSION: AL closely tracks refractive status with range-dependent coupling. Females show longer AL without SE shifts, implying anterior segment compensation.
CLINICAL RELEVANCE: The relationship between vitamin D status and eyehealth is important, as vitamin D is known to play a role in maintaining theintegrity of the tear film, which is important for overall eye function. BA...CLINICAL RELEVANCE: The relationship between vitamin D status and eyehealth is important, as vitamin D is known to play a role in maintaining theintegrity of the tear film, which is important for overall eye function. BACKGROUND: Vitamin D insufficiency has been associated withvarious ocular conditions, including dry eyes. This study aimed to examine thedifferences in tear meniscus parameters between patients with serum vitamin Dinsufficiency and healthy controls without symptomatic dry eye disease. METHODS: A total of 68 participants (34 in each group) wereincluded. Tear meniscus parameters were measured with anterior segment spectraldomain optical coherence tomography (SD-OCT) and images were analysed by ImageJsoftware. Tear meniscus parameters of individuals with low serum vitamin Dlevels were comprehensively evaluated and compared to healthy controls. Tearmeniscus height (TMH) was evaluated as the primary outcome measure. Tearmeniscus depth (TMD), turbidity (TMT), percentage of area covered by particlesin the meniscus (PAOP), ocular surface disease index (OSDI), tear break-up time(TBUT) and Schirmer test results were evaluated. RESULTS: OSDI, Schirmer, and TBUT parameters were within thenormal range in both groups. However, the OSDI score was significantly higherin the low serum vitamin D group, and Schirmer and TBUT scores weresignificantly better in healthy controls ( < 0.05 for all). Moreover, TMH andTMD values were significantly lower in the low serum vitamin D group (TMH: = 0.033, Cohen's d = -0.09; TMD: = 0.041, Cohen's d = -0.07). No significantdifferences were observed in PAOP and TMT values". CONCLUSION: Lower TMH and TMD levels were observed in tear meniscus parameters in patientswith vitamin D insufficiency compared to healthy controls, suggesting thatvitamin D status may play a role in ocular surface health.
Ocular genetics research has seen tremendous growth in the last two decades. Understanding the genetic basis of eye diseases helps researchers comprehend their heritability, uncover disease mechanisms, and develop target...Ocular genetics research has seen tremendous growth in the last two decades. Understanding the genetic basis of eye diseases helps researchers comprehend their heritability, uncover disease mechanisms, and develop targeted gene therapies. This evolving knowledge is changing the clinical management of many eye conditions, from diagnostics and gene-based therapies for patients with previously untreatable monogenic eye diseases, to risk stratification and personalised management of complex conditions. Despite the limited role of genetics in primary eyecare today, the integration of genetics into optometry practice holds promise for enhancing patient outcomes. Optometrists, as primary eyecare practitioners, play a key role in detecting and managing eye conditions. Therefore, increased engagement from optometrists can assist in identifying patients with genetic eye conditions within the community, supporting shared care and multidisciplinary teams, enhancing participation in research and clinical trials, and providing ongoing monitoring and patient education. Integrating genetics into eyecare requires clinicians to have a clear understanding of the role of genetics in rare and common eye diseases, genomic literacy education for primary care practitioners, and multidisciplinary networks for improved communication and coordinated care. This review aims to provide an evidence-based update on recent advances in genetic technologies for eye diseases. It discusses current evidence on the role of genetics in monogenic and polygenic eye diseases, and examines the applications of genetics in eyecare, including diagnosis, risk stratification, and emerging treatments. Additionally, it highlights the role of primary eyecare professionals within a multidisciplinary approach.
Microbial keratitis is a major cause of monocular blindness worldwide. Trauma and contact lens wear are major risk factors. Bacteria are a major cause, but fungi, viruses, and can also cause the disease. Therapeutic opt...Microbial keratitis is a major cause of monocular blindness worldwide. Trauma and contact lens wear are major risk factors. Bacteria are a major cause, but fungi, viruses, and can also cause the disease. Therapeutic options are dwindling with the rise of antimicrobial resistance in all of these microbes, but especially bacteria. Infection with resistant strains results in worse clinical outcomes. New antimicrobial therapies are being developed but most have yet to be either used to treat ocular infections or become commercially available. For bacterial keratitis, antimicrobial peptides (AMPs) are a potential new option, as are bacteriophages and even bacteria that eat other bacteria or maggot secretions. For fungal keratitis, ocular natamycin, with oral ketoconazole or voriconazole treatments, offer improved outcomes for severe cases. For viral keratitis, AMPs again offer hope as new therapeutics, as do RNA interference and CRISPR-Cas systems. The recent release of a commercially available polyhexamethylene biguanide eye drop is a step forward, but new therapies that can kill both trophozoites and cysts are still needed. Beyond antibiotics, photoactivated chromophores for keratitis-corneal collagen cross-linking and photodynamic therapy have been successfully used. Therapies for large ulcers or scarring include corneal gluing, tissue scaffolds such as amniotic membrane or conjunctival flaps, and tissue replacement through penetrating or lamellar keratoplasty.
Over 100 years ago, Professor Foucher of Université Laval in Montreal (Canada) suggested that myopia was the result of an interaction between genetics and the visual environment, implying a Darwinian response to our chan...Over 100 years ago, Professor Foucher of Université Laval in Montreal (Canada) suggested that myopia was the result of an interaction between genetics and the visual environment, implying a Darwinian response to our changing world. His words are still relevant today. Over 30,000 articles have been published since he spoke then. Have his questions been answered? What has been learned from this body of research, particularly in the last 25 years? The purpose of this paper is to review the scientific evidence on myopia and to give clinical significance to the results and conclusions presented. It is therefore not a conventional review. More specifically, this work covers the major trends that have characterised myopia research, allowing us to refine our understanding of the mechanisms leading to the onset and development of myopia and to assess the effectiveness of optical and pharmacological methods for its treatment. This is a clinically oriented text that helps to understand why the strategies used to treat myopia produce certain results but also highlights their limitations. It opens up new perspectives. Science has indeed answered many questions about myopia. But it has also raised many more that need to be addressed in future research notably to facilitate the most accurate prediction of the evolution of a particular individual and his or her response to a given strategy.
In response to the growing incidence of digital eye strain, a variety of spectacle and contact lens interventions have been introduced and are frequently prescribed in clinical and retail settings. However, the evidence...In response to the growing incidence of digital eye strain, a variety of spectacle and contact lens interventions have been introduced and are frequently prescribed in clinical and retail settings. However, the evidence supporting their effectiveness remains limited and inconclusive. This narrative review explores the real-world implementation of lens-based interventions for digital eye strain, focusing on how contextual factors influence prescribing practices. Using the Consolidated Framework for Implementation Research, the review examines the characteristics of these interventions, the outer setting in which they are prescribed, individuals involved in their adoption, and the processes that support or hinder their integration into routine care. Findings reveal that prescribing is often driven more by societal demand, commercial pressures, and clinician perceptions than by robust clinical evidence. Blue light filtering and anti-reflective coated spectacle lenses are commonly recommended, while contact lens interventions are less frequently studied but increasingly marketed. The review highlights a disconnect between evidence and practice and underscores the need for more rigorous research and context-specific clinical guidance to support evidence-based prescribing for digital eye strain.
CLINICAL RELEVANCE: Oxidative stress and elevated reactive oxygen species (ROS) are implicated in corneal pathologies such as keratoconus. Understanding how scleral lens (SL) wear influence these mechanisms is important...CLINICAL RELEVANCE: Oxidative stress and elevated reactive oxygen species (ROS) are implicated in corneal pathologies such as keratoconus. Understanding how scleral lens (SL) wear influence these mechanisms is important for optimizing patient management. BACKGROUND: To assess the alteration in ROS level of keratoconic eyes wearing SL. METHODS: Ocular surface tears (T) were collected at baseline and 6 hours of lens wear (T) on Day 1 and 1 month from 26 keratoconic eyes. SL fluid reservoir (SL) was collected after 6 hours of lens wear on Day 1 (SL Day 1) and at 1 month (SL 1 month). ROS levels were measured using fluorimetry from Schirmer's strip tear samples and the SL samples. Visual acuity, Schirmer's values, and Ocular Surface Disease index questionnaire was also assessed. RESULTS: The ROS levels of T 1 month showed significant reduction after 6 hours of SL wear ( < 0.001). Similarly, the ROS level of SL decreased after 1 month of SL wear compared to Day 1 ( = 0.007). ROS level in SL at Day 1 and 1 month showed significant reduction when compared to T 1 month value ( = 0.002, < 0.001 respectively). A statistically significant increase in T value was noted at 1 month time point when compared to day 1 values ( = 0.005). The baseline ROS levels were higher in collagen cross-linked eyes ( = 0.01), while non-collagen cross-linked eyes showed a reduction in ROS levels of SL ( = 0.01) after 1 month of SL wear. Visual acuity and ocular surface disease index score showed significant improvement after 6 hours and 1 month compared to baseline ( < 0.001 and < 0.001). CONCLUSION: ROS level reduced in the SL after 1 month and in tears after 6 hours with SL in KC patients. This indicates the effectiveness of SL in reducing ROS level of SL which might have association with keratoconus pathogenesis, warrants further analysis.
Digital eye strain (DES) is a group of eye- and vision-related problems elicited by engagement with screens. Over half of screen users experience its symptoms, which include eyestrain, headaches, blurred vision, dry eyes...Digital eye strain (DES) is a group of eye- and vision-related problems elicited by engagement with screens. Over half of screen users experience its symptoms, which include eyestrain, headaches, blurred vision, dry eyes, and neck and shoulder pain. Although contact lenses are a popular option for the correction of refractive error, their role in the aetiology and management of DES is still emerging. Recent review publications on DES only briefly discuss contact lenses. Thus, there is a need (1) to synthesise the current body of literature that has examined the relationship between contact lenses and DES and (2) to identify gaps in the literature that are barriers to employing contact lenses to manage DES. The purpose of this narrative review is to evaluate evidence of ways in which contact lenses may contribute to and may help relieve DES. Although there is little direct evidence to support or refute the use of contact lenses for the management of DES, advances in contact-lens technology to maintain the ocular surface and to correct vision at multiple distances in multiple gazes support the potential of future research. Moreover, there is little high-quality evidence that blue-light filters reduce the symptoms of DES. Nevertheless, eye care professionals should consider the aforementioned potential benefits of wearing contact lenses during computer tasks, versus possible lens-associated ocular-surface disruption and residual astigmatism, when discussing management options with patients. Future gains in knowledge of the interaction between DES and contact lenses will have significance to eye care professionals and to their patients.
CLINICAL RELEVANCE: Facial paralysis (FP) often leads to ocular surfacedisorders due to delayed or incomplete blinking. BACKGROUND: This study aimed to evaluate the ocular surface andmeibomian glands (MG) in patients wit...CLINICAL RELEVANCE: Facial paralysis (FP) often leads to ocular surfacedisorders due to delayed or incomplete blinking. BACKGROUND: This study aimed to evaluate the ocular surface andmeibomian glands (MG) in patients with unilateral FP. METHODS: A total of 26 patients with unilateral FP were included.Invasive tear film break-up time (TF-BUT), ocular surface staining score,Schirmer II test, total eyelid score, and MG secretion score were assessed.Non-contact meibography was used to evaluate the percentage of MG loss area,meiboscore, and morphological features (thickening, thinning, tortuosity,fluffy areas, shortening, ghost areas) of the MGs. RESULTS: TF-BUT and Schirmer II test values were significantlylower in the FP group ( < 0.001 and = 0.001, respectively). The Oxfordstaining score, MG expressibility score, and total eyelid score weresignificantly higher in the FP group ( < 0.001, = 0.003, and = 0.005,respectively). Meiboscore values were higher in both the upper and lowereyelids in the FP group compared to the control group, with a statisticallysignificant difference only in the lower eyelid ( = 0.270 for upper and = 0.039 for lower). The presence of MG thickening wasremarkable in the FP group. The House-Brackmann grade was identified as theonly independent factor affecting both upper and lower eyelid meiboscores. CONCLUSION: Facial paralysis impairs ocular surface parameters andincreases lid margin abnormalities. It is associated with higher meiboscoresand deterioration in meibomian gland morphology.
CLINICAL RELEVANCE: Rigid gas permeable (RGP) contact lenses effectively correct special refractive errors in young children when spectacles fail, supporting visual development. BACKGROUND: To analyse the visual outcomes...CLINICAL RELEVANCE: Rigid gas permeable (RGP) contact lenses effectively correct special refractive errors in young children when spectacles fail, supporting visual development. BACKGROUND: To analyse the visual outcomes of young children (under 6 years) with special refractive errors corrected using RGP contact lenses during the visual development. METHODS: This retrospective study included 50 young children fitted with RGP lenses at Beijing Tongren Eye Centre (2019-2024). Special refractive errors included ultra-high hyperopia due to aphakia, ultra-high myopia (spherical equivalent≤-9.00D), high astigmatism (astigmatism ≥2.00D), and high anisometropia (interocular difference ≥3.00D). Some anisometropia cases had coexisting ocular lesions (myelinated retinal nerve fibres, familial exudative vitreoretinopathy, persistent pupillary membrane). All children were > 4.5 years at final visit with ≥6 months RGP wear. We compared the changes in best-corrected visual acuity (BCVA) before and after RGP contact lens wear in these children and analysed their final visual outcomes. Binocular function was considered 'good' if the Worth 4-dot test showed fusion at near and far distances, with stereoacuity ≤100 seconds of arc. RESULTS: Median age at RGP initiation was 3.16 years (interquartile range (IQR) 2,4), with a median wear duration of 2 years (IQR 1,3.17). BCVA improved significantly from 1.10 logMAR (IQR 1.23,1.01) to 0.30 logMAR (IQR 0.50,0.10) ( < 0.001). A total of 28 patients (56%) achieved a BCVA of 6/12 or better, with 17 showing good binocular function. The highest binocular function rates were in groups with ultra-high myopia (50%), high astigmatism (67%), and pure high anisometropia (50%). None of the nine patients with coexisting ocular lesions achieved good binocular function. CONCLUSIONS: RGP lenses significantly improve BCVA in young children with special refractive errors. The best results were observed in cases of refractive errors alone, while those with other ocular lesions showed limited but notable improvements from baseline.