The effect of topical 1 % atropine on ocular dimensions and diurnal rhythms of the human eye.

The effect of topical 1 % atropine on the diurnal rhythms of the human eye was investigated. Participants wore an activity monitor on Days 1-7. A set of measures (epochs) encompassing intraocular pressure (IOP), ocular biometry, and retinal imaging were obtained on Day 7 (baseline), followed by eight epochs on Day 8, and one on Day 9 from both eyes of healthy participants (n = 22, 19-25 years). The sleep time of participants (collected via actigraphy) was used as a reference in scheduling epochs. Topical 1 % atropine was instilled in the dominant eye on Day 8, 2 h after habitual wake time, using the fellow eye as control (paired-eye design). Sinusoids with a 24-h period were fitted to the data, and a non-linear mixed-effects model was used to estimate rhythmic statistics. There were no interocular differences in any of the measured parameters at baseline. Comparing pre- versus post-atropine in treated eyes revealed lower IOP, deeper anterior chamber (ACD), decreased crystalline lens thickness and shorter axial length (AL). The same trends were observed when comparing atropine-treated versus fellow control eyes, except for IOP and AL (no differences). Both atropine-treated and fellow control eyes showed significant diurnal variations in all ocular parameters, with atropine-treated eyes revealing larger AL and retinal thickness amplitudes, smaller vitreous chamber depth (VCD) amplitudes, and a significant phase advancement for ACD and VCD. There were no interocular differences in choroidal thickness rhythms. In conclusion, while ocular diurnal rhythms persisted after instillation of 1 % atropine, many rhythmic parameters were altered.

Seasonal and Annual Change in Physiological Ocular Growth of 7- to 11-Year-Old Norwegian Children.

Purpose: To investigate seasonal and annual change in physiological eye growth in Norwegian school children. Methods: Measurements of ocular biometry, non-cycloplegic spherical equivalent autorefraction (SER), and choroidal thickness (ChT) were obtained for 92 children (44 females) aged 7 to 11 years at four time points over a year (November 2019-November 2020). Seasons (3- and 5-month intervals) were classified as winter (November-January), winter-spring (January-June), and summer-autumn (June-November). Cycloplegic SER was obtained in January and used to group children. The seasonal and annual changes were tested with a linear mixed-effects model (P values were adjusted for multiple comparisons). Results: All the children experienced annual ocular growth, irrespective of SER, but less so during the summer-autumn. The baseline SER was lower (P < 0.001), axial length (AL) was longer (P < 0.038), and choroids were thicker in 10- to 11-year-old than 7- to 8-year-old mild hyperopes (P = 0.002). Assuming mild hyperopes (n = 65) experience only physiological eye growth, modeling revealed seasonal and annual increases in AL across sex and age (P < 0.018), with less change during the summer-autumn than winter-spring. The 7- to 8-year-olds had a larger decrease annually and over winter-spring in SER (P ≤ 0.036) and in ChT over winter-spring than the 10- to 11-year-olds (P = 0.006). Conclusions: There were significant seasonal and annual changes in AL in children who had physiological eye growth irrespective of age within this cohort. Annual changes in SER and seasonal choroidal thinning were only observed in 7- to 8-year-old children. This indicates continued emmetropization in 7- to 8-year-olds and a transition to maintaining emmetropia in 10- to 11-year-olds.

Myopia management algorithm. Annexe to the article titled Update and guidance on management of myopia. European Society of Ophthalmology in cooperation with International Myopia Institute.

Myopia is becoming increasingly common in young generations all over the world, and it is predicted to become the most common cause of blindness and visual impairment in later life in the near future. Because myopia can cause serious complications and vision loss, it is critical to create and prescribe effective myopia treatment solutions that can help prevent or delay the onset and progression of myopia. The scientific understanding of myopia's causes, genetic background, environmental conditions, and various management techniques, including therapies to prevent or postpone its development and slow its progression, is rapidly expanding. However, some significant information gaps exist on this subject, making it difficult to develop an effective intervention plan. As with the creation of this present algorithm, a compromise is to work on best practices and reach consensus among a wide number of specialists. The quick rise in information regarding myopia management may be difficult for the busy eye care provider, but it necessitates a continuing need to evaluate new research and implement it into daily practice. To assist eye care providers in developing these strategies, an algorithm has been proposed that covers all aspects of myopia mitigation and management. The algorithm aims to provide practical assistance in choosing and developing an effective myopia management strategy tailored to the individual child. It incorporates the latest research findings and covers a wide range of modalities, from primary, secondary, and tertiary myopia prevention to interventions that reduce the progression of myopia.

Rod and Cone Dark Adaptation in Congenital Aniridia and Its Association With Retinal Structure.

Purpose: To characterize the association between dark-adapted rod and cone sensitivity and retinal structure in PAX6-related aniridia. Methods: Dark-adaptation curves were measured after a 5-minute exposure to bright light with red (625 nm) and green (527 nm) 2° circular light stimuli presented at ≈20° temporal retinal eccentricity in 27 participants with aniridia (nine males; 11-66 years old) and 38 age-matched healthy controls. A two-stage exponential model was fitted to each participant's responses to determine their cone and rod thresholds over time. The thicknesses of macular inner and outer retinal layers were obtained from optical coherence tomography images in 20 patients with aniridia and the 38 healthy controls. Aniridia-associated keratopathy (AAK) grade (0-3) and lens opacities were quantified by clinical examination of the anterior segment. Results: The rod-cone break time was similar between patients with aniridia and healthy controls. Dark-adapted cone and the rod thresholds were higher in aniridia compared with healthy controls. In aniridia, foveal outer retinal layer thickness correlated with both final cone and rod thresholds. A multiple regression model indicated that foveal outer retinal layer thickness and age were the main explanatory variables to predict both final cone and rod thresholds in aniridia when the AAK grade was 2 or less. Conclusions: The results show that both rod- and cone-related functions are affected in PAX6-related aniridia and suggest that retinal anatomical and physiological changes extend beyond the area commonly studied in this condition: the central macula.

Comparing ocular biometry and autorefraction measurements from the Myopia Master with the IOLMaster 700 and the Huvitz HRK-8000A autorefractor.

PURPOSE: To compare axial length (AL) and corneal radius (CR) measured with the Oculus Myopia Master and the Zeiss IOLMaster 700, and cycloplegic refractive error measured with the Myopia Master and the Huvitz Auto Ref/Keratometer (HRK-8000A). METHODS: The study included both eyes of 74 participants (16 male), with a mean (SD) age of 22.8 (3.7) years. The parameters indicated were measured under cycloplegia with these instruments: Myopia Master (AL, CR and refractive error), IOLMaster 700 (AL and CR) and HRK-8000A (refractive error and CR). Bland-Altman plots with mixed effects 95% limits of agreement (LoA) and corresponding 95% confidence intervals were used to assess the agreement in ocular biometry between the Myopia Master and the IOLMaster 700, and for refractive error between the Myopia Master and the HRK-8000A. RESULTS: The analysis included 139 eyes, of which 52 were myopic (spherical equivalent refractive error, SER ≤ -0.50 D), 32 emmetropic and 55 hyperopic (SER ≥ 0.50 D). The 95% LoA for AL between the Myopia Master and IOLMaster 700 was -0.097 to 0.089 mm. There was no mean difference in AL [mean (SD) = -0.004 (0.047) mm, p = 0.34]. There was a significant difference in mean CR, with that measured with the Myopia Master being flatter than that found with the IOLMaster 700 [0.035 (0.028) mm, p < 0.001]. The 95% LoA for CR was -0.02 to 0.09 mm. Compared with HRK-8000A, the Myopia Master measured a significantly more negative SER [-0.19 (0.33) D, p < 0.001], with 95% LoA of -0.86 to 0.46 D. CONCLUSION: The LoA for measurements of SER, CR and AL when comparing the Myopia Master with the HRK-8000A and the IOLMaster 700 were wider than deemed acceptable for making direct comparisons. This indicates that the instruments cannot be used interchangeably in clinical practice or research.

Seasonal Variation in Diurnal Rhythms of the Human Eye: Implications for Continuing Ocular Growth in Adolescents and Young Adults.

Purpose: To investigate the diurnal rhythms in the human eye in winter and summer in southeast Norway (latitude 60°N). Methods: Eight measures (epochs) of intraocular pressure, ocular biometry, and optical coherence tomography were obtained from healthy participants (17-24 years of age) on a mid-winter's day (n = 35; 6 hours of daylight at solstice) and on a day the following summer (n = 24; 18 hours of daylight at solstice). Participants wore an activity monitor 7 days before measurements. The epochs were scheduled relative to the individual's habitual wake and sleep time: two in the day (morning and midday) and six in the evening (every hour until and 1 hour after sleep time). Saliva was collected for melatonin. A linear mixed-effects model was used to determine significant diurnal variations, and a sinusoid with a 24-hour period was fitted to the data with a nonlinear mixed-effects model to estimate rhythmic statistics. Results: All parameters underwent significant diurnal variation in winter and summer (P < 0.002). A 1-hour phase advance was observed for melatonin and ocular axial length in the summer (P < 0.001). The degree of change in axial length was associated with axial length phase advance (R2 = 0.81, P < 0.001) and choroidal thickening (R2 = 0.54, P < 0.001) in summer. Conclusions: Diurnal rhythms in ocular biometry appear to be synchronized with melatonin secretion in both winter and summer, revealing seasonal variation of diurnal rhythms in young adult eyes. The association between axial length and seasonal changes in the phase relationships between ocular parameters and melatonin suggests a between-individual variation in adaptation to seasonal changes in ocular diurnal rhythms.

A Systematic Review of the Effects of Second-Eye Cataract Surgery on Motor Function.

Cataract removal surgery is one of the most commonly performed surgical procedure in developed countries. The financial and staff resource cost that first-eye cataract surgery incurs, leads to restricted access to second-eye cataract surgery (SES) in some areas, including the United Kingdom. These restrictions have been imposed despite a lack of knowledge about the impact of not performing SES on visuo-motor function. To this end, a systematic literature review was carried out, with the aim of synthesising our present understanding of the effects of SES on motor function. Key terms were searched across four databases, PsycINFO, Medline, Web of Science, and CINAHL. Of the screened studies (K = 499) 13 met the eligibility criteria. The homogeneity between participants, study-design and outcome measures across these studies was not sufficient for meta-analyses and a narrative synthesis was carried out. The evidence from objective sources indicates a positive effect of SES on both mobility and fall rates, however, when considering self-report measures, the reduction in falls associated with SES becomes negligible. The evidence for any positive effect of SES on driving is also mixed, whereby SES was associated with improvements in simulated driving performance but was not associated with changes in driving behaviours measured through in vehicle monitoring. Self-report measures of driving performance also returned inconsistent results. Whilst SES appears to be associated with a general trend towards improved motor function, more evidence is needed to reach any firm conclusions and to best advise policy regarding access to SES in an ageing population. Systematic Review Registration: https://osf.io/7hne6/, identifier INPLASY2020100042.

Laboured reading and musculoskeletal pain in school children - the role of lifestyle behaviour and eye wear: a cross-sectional study.

BACKGROUND: Lifestyle behaviour in children and adolescents has become increasingly sedentary and occupied with digital work. Concurrently, there has been an increase in the prevalence of headache, neck- and low back pain, which are leading causes of disability globally. Extensive near work and use of digital devices are demanding for both the visual system and the upper body head-stabilizing musculature. Uncorrected vision problems are present in up to 40% of Nordic school children, and a lack of corrective eye wear may cause eyestrain, musculoskeletal pain and headache. The aim of this study was to investigate associations between laboured reading, musculoskeletal pain, uncorrected vision, and lifestyle behaviours in children and adolescents. METHODS: This was a cross-sectional study with a total of 192 Norwegian school children aged 10-11 and 15-16 years. As a part of a school vision testing program, the children completed an online questionnaire about general and ocular health, socioeconomic status, academic ambition, near work and related symptoms, upper body musculoskeletal pain, and physical and outdoor activities. RESULTS: The 15-16-year-olds had a more indoor, sedentary, digital-based lifestyle with higher academic demands, compared with the 10-11-year-olds. Concurrently, reading became more laboured and upper body musculoskeletal pain increased with age. Girls reported more symptoms, higher academic ambitions, and more time spent on schoolwork and reading, compared with boys. Non-compliance in wearing prescribed eye wear (glasses or contact lenses), increased use of near digital devices, and experiencing visual stress (glare) were positively associated with laboured reading and upper body musculoskeletal pain. CONCLUSIONS: A screen-based lifestyle with high academic demands challenges the ability to sustain long hours of static, intensive near work. Extensive near work tires the visual system and upper body musculature and provokes laboured reading and musculoskeletal pain symptoms. This study emphasizes the importance of regular eye examinations in school children, and the need to raise awareness among children, parents, and school- and health personnel about the importance of optimal vision and visual environment for academic performance and health.

Human Foveal Cone and RPE Cell Topographies and Their Correspondence With Foveal Shape.

Purpose: To characterize the association between foveal shape and cone and retinal pigment epithelium (RPE) cell topographies in healthy humans. Methods: Multimodal adaptive scanning light ophthalmoscopy and optical coherence tomography (OCT) were used to acquire images of foveal cones, RPE cells, and retinal layers in eyes of 23 healthy participants with normal foveas. Distributions of cone and RPE cell densities were fitted with nonlinear mixed-effects models. A linear mixed-effects model was used to examine the relationship between cone and RPE inter-cell distances and foveal shape as obtained from the OCT scans of retinal thickness. Results: The best-fit model to the cone densities was a power function with a nasal-temporal asymmetry. There was a significant linear relationship among cone and RPE cell spacing, foveal shape, and foveal cell topography. The model predictions of the central 10° show that the contributions of both the cones and RPE cells are necessary to account for foveal shape. Conclusions: The results indicate that there is a strong relationship between cone and RPE cell spacing and the shape of the human adolescent and adult fovea. This finding adds to the existing evidence of the critical role that the RPE serves in fetal foveal development and through adolescence, possibly via the imposition of constraints on the number and distribution of foveal cones.

Limitation of standard pseudoisochromatic plates in identifying colour vision deficiencies when compared with genetic testing.

PURPOSE: The Ishihara pseudoisochromatic (PIC) plate test is the most used test for identifying red-green colour-deficient individuals, but it is not known how the Ishihara results compare with that of genetics testing. Here, the outcome of genotype analysis of OPN1LW and OPN1MW was compared with that of the Ishihara (24-plate ed., 1964) and the Hardy-Rand-Rittler (4th ed. 2002) PIC plate tests. METHODS: Healthy participants with normal habitual visual acuity (n = 454, 16-24 years; 193 males; logMAR ≤ 0.00) gave saliva samples for opsin gene analysis and performed the two PIC plate tests as part of a cross-sectional study. The criteria for failing the PIC tests were according to manufacturers' instructions. DNA was extracted and used in genotyping assays of OPN1LW and OPN1MW genes from each participant using the Agena MassArray genotyping system. RESULTS: Ten male (5.2%) and 3 (1.1%) female participants were identified as red-green colour deficient based on PIC tests alone. The combination of MassArray and PIC test results identified 10.4% of male and 0.8% of female participants to be colour deficient (males: 0.5% protan and 9.9% deutan; females: 0.8% deutan). Hardy-Weinberg calculations based on male frequencies from combining the MassArray and the PIC test results gave female frequency estimates of colour deficiency and carriers closely matching measured frequencies. CONCLUSIONS: MassArray identified twice as many colour-deficient males as identified from PIC tests alone. Combining results from MassArray and the PIC tests proves to be more reliable than any single test at correctly identifying red-green colour-deficient individuals and carriers.

Exploring the effects of degraded vision on sensorimotor performance.

PURPOSE: Many people experience unilateral degraded vision, usually owing to a developmental or age-related disorder. There are unresolved questions regarding the extent to which such unilateral visual deficits impact on sensorimotor performance; an important issue as sensorimotor limitations can constrain quality of life by restricting 'activities of daily living'. Examination of the relationship between visual deficit and sensorimotor performance is essential for determining the functional implications of ophthalmic conditions. This study attempts to explore the effect of unilaterally degraded vision on sensorimotor performance. METHODS: In Experiment 1 we simulated visual deficits in 30 participants using unilateral and bilateral Bangerter filters to explore whether motor performance was affected in water pouring, peg placing, and aiming tasks. Experiment 2 (n = 74) tested the hypothesis that kinematic measures are associated with visuomotor deficits by measuring the impact of small visual sensitivity decrements created by monocular viewing on sensorimotor interactions with targets presented on a planar surface in aiming, tracking and steering tasks. RESULTS: In Experiment 1, the filters caused decreased task performance-confirming that unilateral (and bilateral) visual loss has functional implications. In Experiment 2, kinematic measures were affected by monocular viewing in two of three tasks requiring rapid online visual feedback (aiming and steering). CONCLUSIONS: Unilateral visual loss has a measurable impact on sensorimotor performance. The benefits of binocular vision may be particularly important for some groups (e.g. older adults) where an inability to complete sensorimotor tasks may necessitate assisted living. There is an urgent need to develop rigorous kinematic approaches to the quantification of the functional impact of unilaterally degraded vision and of the benefits associated with treatments for unilateral ophthalmic conditions to enable informed decisions around treatment.

The Relationship Between Perifoveal L-Cone Isolating Visual Acuity and Cone Photoreceptor Spacing-Understanding the Transition Between Healthy Aging and Early AMD.

Background: Age-related macular degeneration (AMD) is a multifactorial degenerative disorder that can lead to irreversible loss of visual function, with aging being the prime risk factor. However, knowledge about the transition between healthy aging and early AMD is limited. We aimed to examine the relationship between psychophysical measures of perifoveal L-cone acuity and cone photoreceptor structure in healthy aging and early AMD. Methods and Results: Thirty-nine healthy participants, 10 with early AMD and 29 healthy controls were included in the study. Multimodal high-resolution retinal images were obtained with adaptive-optics scanning-light ophthalmoscopy (AOSLO), optical-coherence tomography (OCT), and color fundus photographs. At 5 degrees retinal eccentricity, perifoveal L-cone isolating letter acuity was measured with psychophysics, cone inner segment and outer segment lengths were measured using OCT, while cone density, spacing, and mosaic regularity were measured using AOSLO. The Nyquist sampling limit of cone mosaic (N c ) was calculated for each participant. Both L-cone acuity and photoreceptor inner segment length declined with age, but there was no association between cone density nor outer segment length and age. A multiple regression showed that 56% of the variation in log L-cone acuity was accounted for by N c when age was taken into account. Six AMD participants with low risk of progression were well within confidence limits, while two with medium-to-severe risk of progression were outliers. The observable difference in cone structure between healthy aging and early AMD was a significant shortening of cone outer segments. Conclusion: The results underscore the resilience of cone structure with age, with perifoveal functional changes preceding detectable changes in the cone photoreceptor mosaic. L-cone acuity is a sensitive measure for assessing age-related decline in this region. The transition between healthy aging of cone structures and changes in cone structures secondary to early AMD relates to outer segment shortening.

IMI Risk Factors for Myopia.

Risk factor analysis provides an important basis for developing interventions for any condition. In the case of myopia, evidence for a large number of risk factors has been presented, but they have not been systematically tested for confounding. To be useful for designing preventive interventions, risk factor analysis ideally needs to be carried through to demonstration of a causal connection, with a defined mechanism. Statistical analysis is often complicated by covariation of variables, and demonstration of a causal relationship between a factor and myopia using Mendelian randomization or in a randomized clinical trial should be aimed for. When strict analysis of this kind is applied, associations between various measures of educational pressure and myopia are consistently observed. However, associations between more nearwork and more myopia are generally weak and inconsistent, but have been supported by meta-analysis. Associations between time outdoors and less myopia are stronger and more consistently observed, including by meta-analysis. Measurement of nearwork and time outdoors has traditionally been performed with questionnaires, but is increasingly being pursued with wearable objective devices. A causal link between increased years of education and more myopia has been confirmed by Mendelian randomization, whereas the protective effect of increased time outdoors from the development of myopia has been confirmed in randomized clinical trials. Other proposed risk factors need to be tested to see if they modulate these variables. The evidence linking increased screen time to myopia is weak and inconsistent, although limitations on screen time are increasingly under consideration as interventions to control the epidemic of myopia.

Update and guidance on management of myopia. European Society of Ophthalmology in cooperation with International Myopia Institute.

The prevalence of myopia is increasing extensively worldwide. The number of people with myopia in 2020 is predicted to be 2.6 billion globally, which is expected to rise up to 4.9 billion by 2050, unless preventive actions and interventions are taken. The number of individuals with high myopia is also increasing substantially and pathological myopia is predicted to become the most common cause of irreversible vision impairment and blindness worldwide and also in Europe. These prevalence estimates indicate the importance of reducing the burden of myopia by means of myopia control interventions to prevent myopia onset and to slow down myopia progression. Due to the urgency of the situation, the European Society of Ophthalmology decided to publish this update of the current information and guidance on management of myopia. The pathogenesis and genetics of myopia are also summarized and epidemiology, risk factors, preventive and treatment options are discussed in details.

Tritan color vision deficiency may be associated with an OPN1SW splicing defect and haploinsufficiency.

Here we present evidence implicating disrupted RNA splicing as a potential cause of inherited tritan color vision. Initially we tested 51 subjects for color vision deficiencies. One made significant tritan errors; the others were classified as normal trichromats. The putative tritan subject was the only one of the 51 subjects found to be heterozygous for an OPN1SW gene mutation that disrupts RNA splicing in an in vitro assay. In order to gather further support for the role of the splicing mutation in tritan color vision, the putative tritan subject's mother and sister were examined. They also made tritan errors and had the same OPN1SW gene mutation.

PAX6 Genotypic and Retinal Phenotypic Characterization in Congenital Aniridia.

Purpose: To investigate the association between PAX6 genotype and macular morphology in congenital aniridia. Methods: The study included 37 participants (15 males) with congenital aniridia (aged 10-72 years) and 58 age-matched normal controls (18 males). DNA was isolated from saliva samples. PAX6 exons, intron/exon junctions, and known regulatory regions were amplified in PCR and sequenced. Multiplex ligation-dependent probe amplification (MLPA) was performed to detect larger deletions or duplications in PAX6 or known cis-regulatory regions. Spectral-domain optical coherence tomography images were acquired and segmented semiautomatically. Mean thicknesses were calculated for inner and outer retinal layers within the macula along nasal and temporal meridians. Results: Mutations in PAX6 or regulatory regions were found in 97% of the participants with aniridia. Foveal hypoplasia was observed in all who had a mutation within the PAX6 gene. Aniridic eyes had thinner outer retinal layers than controls, but with large between-individual variation (mean ± SD, 156.3 ± 32.3 µm vs 210.8 ± 12.3 µm, P < 0.001). Parafoveal and perifoveal inner and outer retinal layers were thinner in aniridia. Participants with mutations in noncoding PAX6 regions had thicker foveal outer retinal layers than those with mutations in the PAX6 coding regions (P = 0.04) and showed signs of postnatal development and maturation. Mutations outside the PAX6 gene were associated with the mildest retinal phenotypes. Conclusions: PAX6 mutations are associated with significant thinning of macular inner and outer retinal layers, consistent with misdirected retinal development resulting in abnormal foveal formation and reduced number of neurons in the macula, with mutations in PAX6 coding regions giving the worst outcome.

Characteristics and Utility of Fundus Autofluorescence in Congenital Aniridia Using Scanning Laser Ophthalmoscopy.

Purpose: To investigate fundus autofluorescence (FAF) and other fundus manifestations in congenital aniridia. Methods: Fourteen patients with congenital aniridia and 14 age- and sex-matched healthy controls were examined. FAF images were obtained with an ultra-widefield scanning laser ophthalmoscope. FAF intensity was quantified in the macular fovea and in a macular ring surrounding fovea and related to an internal reference within each image. All aniridia patients underwent an ophthalmologic examination, including optical coherence tomography and slit-lamp biomicroscopy. Results: Mean age was 28.4 ± 15.0 years in both the aniridia and control groups. Fovea could be defined by subjective assessment of FAF images in three aniridia patients (21.4%) and in all controls (P = 0.001). Mean ratio between FAF intensity in the macular ring and fovea was 1.01 ± 0.15 in aniridia versus 1.18 ± 0.09 in controls (P = 0.034). In aniridia, presence of foveal hypoplasia evaluated by biomicroscopy correlated with lack of foveal appearance by subjective analyses of FAF images (P = 0.031) and observation of nystagmus (P = 0.009). Conclusions: Aniridia patients present a lower ratio between FAF intensity in the peripheral and central macula than do healthy individuals. Both subjective and objective analyses of FAF images are useful tools in evaluation of foveal hypoplasia in aniridia.

Emmetropia Is Maintained Despite Continued Eye Growth From 16 to 18 Years of Age.

Purpose: To examine, in Norwegian adolescents, to what degree emmetropia and low hyperopia were maintained from 16 to 18 years of age, and if this was the case, whether it was associated with continued coordinated ocular growth. Methods: Cycloplegic autorefraction and ocular biometry, including crystalline lens thickness, were measured in 93 Norwegian adolescents (mean age: 16.7 ± 0.3 years; 63.4% females) and repeated after 2 years. Crystalline lens power was determined by ray tracing over a 1-mm pupil, based on the Gullstrand-Emsley model. Serum vitamin D3 concentration was measured at follow-up. Results: Emmetropia and low hyperopia (-0.50 diopters [D] < spherical equivalent refractive error [SER] < +2.00 D) were present in 91.4% at baseline and 89.2% at follow-up. The emmetropes and low hyperopes who maintained their refractive error exhibited continued ocular axial growth (+0.059 ± 0.070 mm) together with a decrease in crystalline lens power (-0.064 ± 0.291 D) and a deepening of the anterior chamber (+0.028 ± 0.040 mm). Thinning of the crystalline lens was found in 24%. Overall, the negative change in SER was larger in those with the most negative SER at baseline (R2 = 0.178, P < 0.001), and was associated with increases in vitreous chamber depth and in crystalline lens power (R2 = 0.752, P < 0.001), when adjusted for sex. There was no difference in vitamin D3 level between those who exhibited negative versus positive changes in refractive error. Conclusions: The results show that emmetropic and low hyperopic eyes were still growing in late adolescence, with refractive errors being maintained through a coordinated decrease in crystalline lens power.