Change of refractive state and eye size in children of birth weight less than 1701 g

Early ophthalmic growth deficits in preterm-born children are not compensated for during later development

The renewed focus on eye growth in preterm-born children was primarily triggered by Danish cohort studies, including the Copenhagen Project, which focused on children born from 1959-1961. The retinotoxic effects of excessive oxygen on premature neonates had long been clarified and therapeutically adjusted for. Later, ultrasound oculometry and keratometry established that ocular size deficits, linked to development, also occurred in normally developing children, not just frail outliers. This indicated that general catch-up had not been achieved. This paper discusses whether one early segment of eye development does not occur in preterm, and here even in more robust neonates, without later compensation.

Myopia dominance in preterm infants without and with retinopathy of prematurity: Indian Twin Cities ROP study (ITCROPS) report number 15

PURPOSE

To investigate the refractive error profile and progression in infants with different stages of ROP, without ROP, and those who received laser treatment for ROP.

METHODS

This retrospective study included the data from 838 infants (baseline mean age 3.7 ± 5.4 months) who had premature birth. Among these, 433 infants had one of the stages of ROP and 405 had no ROP. Infants with ROP were sub-divided into stage 1 (n = 76), stage 2 (n = 142), and stage 3 (n = 136) and aggressive posterior ROP, (APROP, n = 79). They were further categorized into those who received treatment (n = 213) and with no treatment for ROP (n = 220). Data from a subset of 117 infants was used to assess the 1-year change in the refractive error. Myopia was defined as spherical equivalent refraction (SER) <-0.50 diopters (D). Eyes with retinal detachment were excluded.

RESULTS

Higher percentage of myopia was found in infants with ROP (39.7%) than no-ROP (19.8%), and it increased with severity of ROP: stage 1: 19.7%, stage 2: 33.8%, stage 3: 45.6%, and 59.5% in APROP. Percentage of myopia doubled in those who underwent treatment for ROP (54.5%) compared to no-treatment group (25.5%). Mean (± SEM) change in SER after 1 year was significantly greater in infants with APROP -4.55 ± 1.38 D and stage 3 ROP -2.28 ± 0.57 D compared to other stages and no-ROP.

CONCLUSION

Myopia was found to be more prevalent in preterm infants in general, and more in the presence of ROP. Preterm infants without or with any form of ROP, particularly those with severe form of ROP and those who received treatment require meticulous periodic refractive error assessment.

Macular Curvature in Adults Born Preterm With and Without ROP: Results from the Gutenberg Prematurity Eye Study

Purpose

This study investigated the effects of prematurity and retinopathy of prematurity (ROP) as well as the associations of the ocular geometry with macular curvature in adults.

Methods

The Gutenberg Prematurity Eye Study is a retrospective cohort study of preterm and full-term participants aged 18 to 52 years with a prospective ophthalmologic examination. The main outcome measure was the macular curvature in the central foveal optical coherence tomography (OCT) scan and its associations with gestational age (GA), birth weight and birth weight percentile, ROP occurrence, ROP treatment, and other perinatal factors were evaluated in univariable and multivariable linear regression analyses. Furthermore, a second model assessed the association of ocular geometry with macular curvature.

Results

In the present study, 550 eyes of 284 adults born preterm and 277 eyes of 139 adults born full-term were examined (aged = 28.7 ± 8.7 years, 240 female subjects). In multivariable analyses for perinatal parameters, ROP treatment (B = -52.44, P = 0.023) and maternal smoking during pregnancy (B = 26.41, P = 0.019) showed an association with macular curvature. Regarding ocular geometric parameters, posterior segment length (B = 9.07, P < 0.001) and subfoveal choroidal thickness (B = -0.26, P < 0.001) were associated with macular curvature, central corneal thickness, anterior chamber depth, lens thickness, and foveal retinal thickness were not associated.

Conclusions

Adults treated for ROP had relatively more negative curvature values compared to the full-term group, indicating a macular protrusion toward the vitreous cave. A thicker subfoveal choroidal thickness was associated with a flatter macular curvature, whereas a longer posterior segment length was associated with a steeper macular curvature indicating the characteristics of the myopic elongation of the eye.

Prevalence and causes of ocular disorders and visual impairment among preterm children in Ethiopia

OBJECTIVE

The aim of this study was to determine the prevalence, causes of ocular disorders and visual impairment among preterm children previously admitted to neonatal intensive care units in Addis Ababa, Ethiopia.

METHODS AND ANALYSIS

A prospective screening survey was conducted from February to June 2019 at the paediatric eye clinic of Menelik II Hospital. Children who were preterm at birth and who attended the eye clinic were included in the study. Data on demographic and neonatal characteristics, neonatal and maternal comorbidities and ocular disorders were collected. OR and univariate analysis were used to identify predictors of ocular diseases and visual impairment.

RESULTS

There were 222 children included in the study with a mean age at presentation of 2.62 years (range 2.08-6.38 years), mean gestational age 34.11 weeks (range 30-36) weeks and mean birth weight 1941.72 g (range 953-3500 g). Nearly two-thirds had ocular disorders with refractive error (51.8%), strabismus (11.3%) and a history of retinopathy of prematurity (ROP) (7.2%) being more common. One-fourth of the children had visual impairment, and the prevalence of amblyopia was 40.1%. Uncorrected refractive errors, strabismus and ROP were causes for visual impairment.

CONCLUSION

Visual impairment and amblyopia are common in Ethiopia. There is a need to develop a screening protocol for ocular disorders for preterm children to enhance early detection and prevention of childhood visual impairment.

Effects of prematurity and retinopathy of prematurity on refractive errors and biometric optic components in school children: results of a tertiary center from Turkey

PURPOSE

To reveal refractive errors, the relationship between refractive errors and optical parameters, and the effect of prematurity and retinopathy of prematurity (ROP) on ocular development in school children with a history of prematurity.

METHODS

Premature children aged 8-12 years were divided into 3 groups as those without ROP (Group 1), with ROP that did not require treatment (Group 2), and with laser-treated ROP (Group 3). Age-matched full-term healthy children were included in the control group. Demographic features were recorded. A detailed ophthalmologic examination was performed. Anterior chamber depth (ACD), trabecular-iris angle (TIA), iris thickness (IT), lens thickness (LT), vitreous body length (VBL), axial length (AL) were measured by ultrasound biomicroscopy (UBM). The results were compared between groups.

RESULTS

Group 3 had the lowest best corrected visual acuity (0.81 ± 0.31 SL), the highest rates of myopia (55.9%) and astigmatism (50.0%). In the premature groups, ACD (p < 0.001), TIA (p < 0.001), IT (p = 0.016), VBL (p < 0.001) and AL (p < 0.001) were lower; LT (p < 0.001) was higher than in the control group. As birth weight (BW) and gestational age (GA) increased, ACD, TIA, VBL and AL increased, and LT decreased (p < 0.001). In the group 3, 35.2% anisometropia, 17.6% of esotropia and 5.9% of exotropia were detected.

CONCLUSIONS

The frequency of myopia, astigmatism, hyperopia and anisometropia is increasing in premature children, especially in cases with laser-treated ROP. Premature cases are characterized by thicker lens, shallower ACD, narrower TIA and shorter AL. Refractive errors, anisometropia, amblyopia and strabismus are important causes of visual impairment in children with laser-treated ROP.

Wide-field digital imaging system for assessing ocular anterior segment development in very preterm infants

Purpose

This study aims to longitudinally investigate developments of the anterior segment in very preterm infants who exhibit normal retinal development outcomes by utilizing a wide-field digital imaging system.

Methods

Between June 2021 and June 2022, neonates with a birth weight of <1500 g and/or a gestational age (GA) of less than 32 weeks were included in this study. The participants underwent regular ocular examinations, including sequential evaluations of the anterior segment and the retina, at intervals of 2-5 weeks, starting from birth and continuing until they reached a corrected GA of 48 weeks. Term neonates were selected as normal controls for the study. The study recorded the weight and GA of subjects at the time of examination, as well as indicators of abnormal development in the anterior segment.

Results

A total of 48 very preterm infants with normal retinal developmental outcomes were enrolled. The control group included 59 full-term infants. Common anterior segment eye abnormalities such as persistent hyperplasia of primary vitreous, persistent pupillary membranes, iris vessels, and anterior chamber angle vessels gradually subsided with the period in very preterm infants. The vascularity of the iris was substantially higher than in term controls (P < 0.05) at term gestation. The imaging of iris vessels and anterior chamber angle vessels in very preterm infants exhibited a decline at 46 and 47 weeks, respectively, which occurred slightly later compared to term infants.

Conclusion

In very preterm infant s with normal outcomes, although the developmental process is delayed, they may form a normal anterior segment structure similar to that of full-term infants in the late stages, which is followed up by the wide-field digital imaging system.

Electroretinographic Responses in Retinopathy of Prematurity Treated Using Intravitreal Bevacizumab or Laser

PURPOSE

Intravitreal injection of bevacizumab (IVB) offers advantages over laser photoablation for treatment of type 1 retinopathy of prematurity (ROP). However, retinal function has not, to date, been quantitatively compared following these interventions. Therefore, electroretinography (ERG) was used compare retinal function among eyes treated using IVB or laser, and control eyes. In addition, among the IVB-treated eyes, ERG was used to compare function in individuals in whom subsequent laser was and was not required.

DESIGN

Prospective clinical cohort study.

METHODS

ERG was used to record dark- and light-adapted stimulus/response functions in 21 children treated using IVB (12 of whom required subsequent laser in at least 1 eye for persistent avascular retina [PAR]). Sensitivity and amplitude parameters were derived from the a-wave, b-wave, and oscillatory potentials (OPs), representing activity in photoreceptor, postreceptor, and inner retinal cells, respectively. These parameters were then referenced to those of 76 healthy, term-born controls and compared to those of 10 children treated using laser only.

RESULTS

In children with treated ROP, every ERG parameter was significantly below the mean in controls. However, these significant ERG deficits did not differ between IVB- and laser-treated eyes. Among children treated using IVB, no ERG parameter was significantly associated with dose or need for subsequent laser.

CONCLUSION

Retinal function was significantly impaired in treated ROP eyes. Function in IVB-treated eyes did not differ from that in laser-treated eyes. Functional differences also did not distinguish those IVB-treated eyes that would subsequently need laser for PAR.

Corneal topography in preterm children aged 2 years to 12 years with or without retinopathy of prematurity

OBJECTIVES

To evaluate corneal topography in full-term and preterm children with or without retinopathy of prematurity (ROP).

METHODS

We enrolled children aged from 2 years to 12 years between January 2019 and May 2021 in the following four groups: full-term (group 1), premature without ROP (group 2), untreated premature with ROP (group 3), and laser-treated and/or intravitreal injection (IVI) of anti-vascular endothelial growth factor (VEGF)-treated premature with ROP (group 4). Corneal topography was measured with the Galilei Placido-dual Scheimpflug analyzer G4 every half year, and was compared among the groups using generalized estimating equation models at approximately 7 years of age.

RESULTS

We included 77, 178, 45, and 131 participants in groups 1, 2, 3, and 4, respectively. The mean (standard deviation) number of visits per patient was 2.9 (1.4). Compared with full-term eyes, premature eyes demonstrated steeper anterior corneal curvature (p = 0.016 and p = 0.008 for the mean and steep K, respectively), higher anterior and posterior corneal astigmatism (p = 0.036 and p = 0.016, respectively), and thinner thinnest pachymetry (p < 0.001). The laser-treated ROP eyes displayed steeper anterior corneal curvature (p = 0.040 for steep K) and higher anterior corneal astigmatism (p = 0.005) than the IVI-treated eyes. Moreover, they exhibited high cone location and magnitude index (1.96) reaching the cut-off for detecting keratoconus (1.82).

CONCLUSIONS

The premature status led to greater corneal ectasia, and laser treatment for ROP caused further corneal steepness. Higher anterior corneal astigmatism was associated with laser treatment. The ROP pathology and IVI anti-VEGF treatment exerted a marginal effect on corneal topography.

Mendelian randomization analyses in ocular disease: a powerful approach to causal inference with human genetic data

Ophthalmic epidemiology is concerned with the prevalence, distribution and other factors relating to human eye disease. While observational studies cannot avoid confounding factors from interventions, human eye composition and structure are unique, thus, eye disease pathogenesis, which greatly impairs quality of life and visual health, remains to be fully explored. Notwithstanding, inheritance has had a vital role in ophthalmic disease. Mendelian randomization (MR) is an emerging method that uses genetic variations as instrumental variables (IVs) to avoid confounders and reverse causality issues; it reveals causal relationships between exposure and a range of eyes disorders. Thus far, many MR studies have identified potentially causal associations between lifestyles or biological exposures and eye diseases, thus providing opportunities for further mechanistic research, and interventional development. However, MR results/data must be interpreted based on comprehensive evidence, whereas MR applications in ophthalmic epidemiology have some limitations worth exploring. Here, we review key principles, assumptions and MR methods, summarise contemporary evidence from MR studies on eye disease and provide new ideas uncovering aetiology in ophthalmology.

Late sequelae of retinopathy of prematurity in adolescence and adulthood

This article provides information about late complications of retinopathy of prematurity (ROP), especially seen in adolescence and adulthood. The majority of ROP patients recover without complications and treatment, but severe ROP cases should be properly treated. Both prematurity itself and the treatment of ROP cause some changes in the anterior (refractive changes, cataract, and glaucoma) and posterior segments (tractional, rhegmatogenous and exudative retinal detachment, vitreous hemorrhage, etc.,) of the eye and predispose to significant lifelong complications. Awareness of these late complications can minimize severe vision loss with proper follow-up and appropriate treatment. Therefore, life-long ophthalmological follow-up is mandatory in all prematures with the diagnosis of ROP.

Refractive outcomes following unilateral laser treatment for type 1 retinopathy of prematurity

PURPOSE

To compare refractive outcomes of infants with type 1 retinopathy of prematurity (ROP) in whom one eye was treated with laser and the fellow eye spontaneously regressed.

METHODS

The medical records of infants who underwent IVB and laser treatment for type 1 ROP or aggressive posterior-ROP between January 2016 and December 2019 were retrospectively evaluated. Infants in whom ROP in the fellow eye regressed and for whom refractive data was available in the record were included in the study. Refractive outcomes of unilaterally treated infants were assessed.

RESULTS

A total of 283 cases were reviewed: of these, 17 experienced spontaneous regression in the fellow eye and were included. All unilateral laser-treated eyes had type 1 ROP in zone Ⅱ. The median age at treatment was 40 weeks' postmenstrual age (IQR, 39-41). The mean spherical equivalent at the last examination was 2.1 ± 2.5 D in treated eyes and 2.50 ± 1.4 D in nontreated eyes, at a mean age of 25.0 ± 9.1 months (P = 0.378). Of the 7 infants who underwent fluorescein angiography, the median of the ratio of the length of the temporal retinal vascularization to the optic disk-to-fovea distance was 3.71 (3.22-3.79) in treated and 4.28 (3.90-4.49) in untreated eyes, at a median age of 18 months (P = 0.018).

CONCLUSIONS

In laser-treated eyes with peripheral zone Ⅱ ROP and with advanced treatment age, we did not observe a significant myopic change compared to the fellow untreated eye.

Effectiveness of early spectacle intervention on visual outcomes in babies at risk of cerebral visual impairment: a parallel group, open-label, randomised clinical feasibility trial protocol

INTRODUCTION

Hypoaccommodation is common in children born prematurely and those with hypoxic ischaemic encephalopathy (HIE), with the potential to affect wider learning. These children are also at risk of longer-term cerebral visual impairment. It is also well recognised that early intervention for childhood visual pathology is essential, because neuroplasticity progressively diminishes during early life. This study aims to establish the feasibility and acceptability of conducting a randomised controlled trial to test the effectiveness of early near vision correction with spectacles in infancy, for babies, at risk of visual dysfunction.

METHODS AND ANALYSIS

This is a parallel group, open-label, randomised controlled (feasibility) study to assess visual outcomes in children with perinatal brain injury when prescribed near vision spectacles compared with the current standard care-waiting until a problem is detected. The study hypothesis is that accommodation, and possibly other aspects of vision, may be improved by intervening earlier with near vision glasses. Eligible infants (n=75, with either HIE or <29 weeks preterm) will be recruited and randomised to one of three arms, group A (no spectacles) and two intervention groups: B1 or B2. Infants in both intervention groups will be offered glasses with +3.00 DS added to the full cycloplegic refraction and prescribed for full time wear. Group B1 will get their first visit assessment and intervention at 8 weeks corrected gestational age (B1) and B2 at 16 weeks corrected gestational age. All infants will receive a complete visual and neurodevelopmental assessment at baseline and a follow-up visit at 3 and 6 months after the first visit.

ETHICS AND DISSEMINATION

The South-Central Oxford C Research Ethics Committee has approved the study. Members of the PPI committee will give advice on dissemination of results through peer-reviewed publications, conferences and societies.

TRIAL REGISTRATION NUMBER

ISRCTN14646770, NCT05048550, NIHR ref: PB-PG-0418-20006.

Visual acuity, amblyopia, and vision-related quality of life in preterm adults with and without ROP: results from the Gutenberg prematurity eye study

Objectives

This study investigated the effects of prematurity and ROP on visual acuity and VRQoL in adults (18–52 years).

Methods

The Gutenberg Prematurity Eye Study is a retrospective cohort study with a prospective ophthalmologic examination. Preterm and full-term participants at an age from 18 to 52 years were included. Distant corrected visual acuity (DCVA) and VRQoL were assessed in participants (892 eyes of 450 individuals aged 28.6 ± 8.6 years, 251 females) grouped into full-term controls (gestational age [GA] at birth ≥37 weeks), preterm participants without ROP and GA 33–36 weeks (group 2), GA 29–32 weeks (group 3), GA ≤ 28 weeks (group 4), non-treated ROP (group 5) and treated ROP (group 6). Main outcome measures were distant corrected visual acuity (DCVA), VRQoL and prevalence of amblyopia.

Results

The DCVA of the better eye correlated (p < 0.001) with GA, birth weight, ROP, ROP treatment, and perinatal adverse events and was poorer in both ROP groups. Visual acuity of <20/200 in the better eye was observed in two participants (4.2%) in the ROP group and one person (6.7%) in the treated ROP group. The prevalence of amblyopia increased in the ROP groups. Compared to full-term controls, visual functioning VRQoL scores were lower in preterm individuals independent of ROP while socioemotional VRQoL scores were only lower in the treated ROP group.

Conclusion

Participants with postnatal ROP and its treatment showed decreased visual acuity and VRQol in adulthood, with amblyopia occurring more frequently in more preterm participants with ROP.

The Association Between Refractive Errors and Breastfeeding in Pakistani Children: A Case-Control Study

Objective

The aim of this study was to determine the association between breastfeeding and the occurrence of refractive errors (REs) among children.

Methodology

This was a (retrospective) case-control study carried out between December 1, 2021, and March 30, 2022, at the Basheeran Umar Eye Hospital in Islamabad, Pakistan, and Sheikh Khalifa bin Zayed Al Nayhan Combined Military Hospital in Rawalakot in Kashmir, Pakistan. A total of 200 participants between the ages of five and 16 years (106 cases with REs and 94 controls without REs) were included in this study. After obtaining informed consent from the parent accompanying the participant, the parent was further interviewed to extract information regarding biodata, breastfeeding, and other parameters including parental myopia, the number of hours spent on outdoor activities, on gadgets, and doing near work; this data was entered into a questionnaire. The participant’s visual acuity was then checked using the Snellen chart. Data were analyzed using SPSS Statistics version 20.0 (IBM Corp., Armonk, NY) and statistical tests such as multivariate regression analysis and chi-square were carried out and odds ratios (OR) were calculated.

Results

There were 74 (37%) females and 126 (63%) males, with 67.5% residing in urban localities and only 32.5% hailing from rural areas. Testing revealed no significant association between REs and area of residence (p=0.97) or the gender of the participant (p=0.74). Hypermetropia was the most common RE among our participants (59.4%).

Breastfeeding was significantly associated with errors of refraction (OR: 27.852, 95% CI: 3.686-210.45, χ²=21.680, p<0.001, degrees of freedom: 1), and we observed a lower risk of REs in children who had been breastfed. There was no association between REs and the number of hours spent outdoors per week or the number of hours spent using gadgets per week. However, there was a significant association between the development of REs and the duration of breastfeeding and the number of hours spent on near work.

Conclusion

This study demonstrates that breastfeeding plays a protective role in the prevention of REs. The type of breastfeeding also had a significant effect on the development of REs, i.e., children exclusively breastfed (regardless of the duration of breastfeeding) were less likely to develop errors of refraction in the future.

Factors associated with refractive outcome in children treated with bevacizumab for retinopathy of prematurity: the importance of retinal vascularization

PURPOSE

To evaluate the factors that may be associated with refractive outcome in eyes treated with intravitreal bevacizumab (IVB) injection for retinopathy of prematurity (ROP).

METHODS

Retrospective case series. Refractive outcomes of 181 infants who were treated with primary IVB for Type I ROP or aggressive ROP, were retrospectively evaluated. According to the pretreatment retinal vascularization, eyes were classified into zone I, zone I-zone II, and zone II groups. The first year, third year, and final refractive error were analyzed. Univariate logistic regression test was performed to evaluate the effect of factors on the development of ≥ 1 diopter (D) myopia.

RESULTS

At the final examination, the mean age was 22.9 ± 10.9 months. The zone II group was more hyperopic than the zone I-zone II and zone I zone groups (P = 0.001). Of the 331 eyes, 17 eyes (5.1%) had high myopia, 50 eyes (15.1%) had low myopia, and 83 eyes (25.1%) had emmetropia. During follow-up, 110 (33.2%) eyes underwent laser treatment. Gestational age, birth weight, neonatal intensive care unit type, the presence of additional laser treatment, number of injections, the type of ROP, and the dose of IVB were not associated with the development of ≥ 1 D myopia. The pretreatment and prelaser retinal zones were associated with the development of ≥ 1 D myopia.

CONCLUSION

The most important factors affecting the refractive outcome in infants who underwent primary IVB treatment was the extent of pretreatment and prelaser retinal vascularization.

Refraction and its development in young adults born prematurely and screened for retinopathy of prematurity

PURPOSE

To evaluate refraction and its development in young adults born prematurely, screened for retinopathy of prematurity, and to compare with individuals of the same age born at term.

MATERIALS AND METHODS

The participants were 59 preterms, with a birthweight of ≤ 1500 g, and 43 term-born controls, all born during 1988-1990. The refraction was measured in cycloplegia, and the spherical equivalent (SE) was calculated. The axial length (AL), anterior chamber depth and corneal radius (CR) were measured, and the AL/CR ratio was calculated.

RESULTS

The mean SE was -0.5 dioptres (D) (SD 2.5) in right eyes (REs) and -0.4 D (SD 2.3) in left eyes (LEs) of preterms, and -0.2 D (SD 1.5) in REs and -0.2 D (SD 1.5) in LEs of controls. The distribution of refraction was wider in the preterm group compared to the control group. In the preterm group, 12% had a SE ≥ 1.5 D, but none of the controls. Ten preterms, but none of the controls, had anisometropia ≥ 1.0 D. The prevalence of astigmatism ≥ 1.0 D was higher in preterms than controls. The SE decreased around 1 D in both preterms and controls from 10 to 25 years of age. The AL and CR were shorter in the preterms; however, the AL/CR ratio was similar in both groups. Within the preterm group, cryotherapy was correlated with astigmatism, but not with SE and anisometropia at this age.

CONCLUSION

Prematurely born individuals had higher prevalence of refractive errors in young adulthood compared to term-born controls.

Functional Ophthalmic Factors Associated With Extreme Prematurity in Young Adults

IMPORTANCE

Children born preterm (<37 weeks' gestation) have a higher risk of visual impairment and ocular morbidities compared peers born at full term. However, the long-term ocular sequelae in adulthood for those born extremely preterm (EP), who have the highest risk of neonatal retinopathy, are unknown.

OBJECTIVE

To evaluate visual function and ocular morbidity in young adults born EP compared with controls born full term.

DESIGN, SETTING, AND PARTICIPANTS

This prospective cohort study of a geographically based birth cohort in the UK and Ireland born from March 1 through December 31, 1995, included 128 participants aged 19 years (born at 22-25 weeks' gestation) and 65 age-matched controls born at full term. Statistical analysis was performed from March 1, 2020, to November 26, 2021.

EXPOSURES

Participants underwent eye examinations as part of a comprehensive outcome evaluation.

MAIN OUTCOMES AND MEASURES

Best-corrected visual acuity, refractive status, contrast sensitivity, color vision, prevalence of strabismus and nystagmus, and patient-reported visual function, measured using the Health Utilities Index Mark 3.

RESULTS

The study comprised 128 participants (256 eyes; 68 female participants [53%]; mean [SD] age, 19.3 [0.5] years) and 65 age-matched controls born at full term (130 eyes; 40 female participants [62%]; mean [SD] age, 19.2 [0.5] years). Compared with control eyes, the mean (SD) best-corrected visual acuity among eyes in the EP group was significantly worse (monocular vision: -0.06 [0.14] logMAR in the control group vs 0.14 [0.38] logMAR in the EP group; P < .001; binocular vision: -0.14 [0.15] logMAR in the control group vs 0.06 [0.37] logMAR in the EP group; P < .001). Participants in the EP group had a significantly higher prevalence of strabismus (36% [46 of 127] vs 0%; P < .001), abnormal ocular motility (15% [19 of 125] vs 0%; P < .001), and nystagmus (13% [16 of 127] vs 0%; P < .001) than the control group. No significant differences between participants in the EP group and controls were observed for refractive error, contrast sensitivity, color vision, or patient-reported visual function. Among the participants in the EP group, 48% of eyes (120 of 250) had no retinopathy of prematurity (ROP), 39% (98 of 250) had ROP not requiring neonatal treatment, and 13% (32 of 250) received cryotherapy or laser ablation for ROP. Within the EP group, there was no significant difference in binocular visual function parameters, prevalence of ocular morbidity, and patient-reported visual function by neonatal ROP status.

CONCLUSIONS AND RELEVANCE

Extreme prematurity is associated with an increased prevalence of visual and ocular deficits in young adulthood; this study suggests that, for individuals born EP, visual and ocular deficits appear to be partially independent of ROP status in the neonatal period but reports similar overall visual function.

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.

The Development of Ocular Biometric Parameters in Premature Infants without Retinopathy of Prematurity

PURPOSE

The aim of this study was to investigate the developmental tendencies and distribution of ocular biometric parameters in premature infants without retinopathy of prematurity (ROP). Axial length (AL), anterior chamber depth (ACD), lens thickness (LT) and vitreous length (VL) were measured, and their relationships with birth weight (BW) and postmenstrual age (PMA) were analyzed during their earliest weeks of life.

METHODS

This cross-sectional cohort study included 633 premature infants. They were divided into nine groups according to their PMA: 32 weeks, 33 weeks, 34 weeks, and onward to 40 weeks. All participants underwent portable slit-lamp examination, RetCam3 and A-scan ultrasound biometry. The following ocular biometric parameters were recorded: AL, ACD, LT and VL. The t-test, one-way analysis of variance, and the multiple regression analysis model were used to analyze the data.

RESULTS

The increases in AL, ACD, LT and VL were 0.14 mm, 0.028 mm, 0.0025 mm and 0.11 mm per week, respectively. AL, ACD, LT and VL were positively correlated with BW (β = 0.000337, 4.234E-5, 2.697E-5, 0.000278, respectively) and PMA (β = 0.142, 0.026, 0.011, 0.103, respectively).

CONCLUSIONS

With maturation, AL and VL increased and ACD deepened, but there was no significant change in LT. The ocular growth parameters were positively correlated with BW and PMA however the correlations were not strong.

Refractive status and optical components of premature babies with or without retinopathy of prematurity at 7 years old

BACKGROUND

This study aimed to investigate the refractive status and optical components of premature babies with or without retinopathy of prematurity (ROP) at 7 years old and to explore the influence of prematurity and ROP on the refractive status and optical components.

METHODS

From January 2009 to February 2011, premature babies receiving fundus photographic screening (FPS) were recruited and divided into non-ROP group and ROP group. Full-term babies matched in age were recruited as controls. Auto-refractometer was employed to detect the corneal refractive power, corneal radius (CR) of curvature and corneal astigmatism, A-scan ultrasonography was performed to detect the anterior chamber depth (ACD), lens thickness (LT), vitreous thickness (VITR) and ocular axial length (AL), and retinoscopy was done following cycloplegia with 1% cyclopentolate in these babies at 7 years old. These parameters were compared among groups, and the correlations of gestational age and birth weight with the refractive status and optical components were further evaluated.

RESULTS

Of 126 subjects, a total of 252 eyes were evaluated in this study, including 50 eyes of 25 subjects in ROP group (pre-threshold stage 1-3), 110 eyes of 55 subjects in non-ROP group and 92 eyes of 46 subjects in control group. The incidence of myopia was the highest in ROP group (9/50, 18%), followed by non-ROP group (11/110; 10%) and control group (6/92; 6.52%). The incidence of hyperopia was the highest in control group (21/92; 22.83%), followed by ROP group (8/50; 16%) and non-ROP group (10/110; 9.09%). The incidence of astigmatism was the highest in ROP group (18/50; 36%), followed by non-ROP group (25/110; 22.73%) and control group (12/92; 13.04%). The corneal astigmatism (-1.58, -1.11, -0.86 DC, P<0.01) and the mean degree of astigmatism (1.38, 1.17, 0.64 DC, P<0.05) in ROP group and non-ROP group were significantly higher than those in control group. The corneal refractive power in ROP group was more potent as compared to non-ROP group and control group (43.98, 43.16, 42.99 D, P<0.05); the corneal curvature in ROP group was significantly higher than that in non-ROP group and control group (7.87, 7.71, 7.67 mm, P<0.05); the ocular AL in ROP group and non-ROP group was significantly shorter than that in control group (2.41, 22.47, 22.78 mm, P<0.05). The LT in ROP group and non-ROP group was markedly thicker than that in control group (4.48, 4.45, 4.37 mm, P>0.05); the ACD in ROP group and non-ROP group was markedly deeper than in control group (3.16, 3.12, 3.21 mm, P>0.05). The gestational age was negatively related to corneal astigmatism (r=-0.208, P=0.013) and astigmatism (r=-0.226, P=0.004), but positively associated with ocular AL (r=0.252, P=0.005). The birth weight was negatively associated with corneal astigmatism (r=-0.30, P<0.001), astigmatism (r=-0.267, P=0.001), corneal refractive power (r=-0.255, P=0.001) and corneal curvature (r=0.242, P=0.001), but positively to ocular AL (r=0.243, P=0.001) and spherical equivalent refraction (SER) (r=0.151, P=0.028).

CONCLUSIONS

(I) Premature babies with or without ROP are susceptible to myopia and astigmatism; (II) low birth weight, prematurity and ROP synergistically influence the development of refractive status and optical components, resulting in myopia and astigmatism; (III) premature babies with or without ROP have increased corneal curvature and LT, which are related to the higher incidence of myopia and astigmatism.

Effects of Hyperoxia on the Refraction in Murine Neonatal and Adult Models

Whether hyperoxia affects the refraction in neonatal and adult mice is unknown. The mice exposed to 85% oxygen at postnatal 8 days (P8d) for 3 days and the mice exposed to normal air were assigned to the neonatal hyperoxia and normoxia groups, respectively. The refraction, the corneal curvature radius (CR) and the axial length (AL) were measured at P30d and P47d. Postnatal 6 weeks (P6w) adult mice were divided into the adult hyperoxia and normoxia groups. These parameters were measured before oxygen exposure, after 1 and 6 weeks, and every 7 weeks. The lens elasticity was measured at P7w and P26w by enucleation. The neonatal hyperoxia group showed a significantly larger myopic change than the neonatal normoxia group (P47d −6.56 ± 5.89 D, +4.11 ± 2.02 D, p < 0.001), whereas the changes in AL were not significantly different (P47d, 3.31 ± 0.04 mm, 3.31 ± 0.05 mm, p = 0.852). The adult hyperoxia group also showed a significantly larger myopic change (P12w, −7.20 ± 4.09 D, +7.52 ± 2.54 D, p < 0.001). The AL did not show significant difference (P12w, 3.44 ± 0.03 mm, 3.43 ± 0.01 mm, p = 0.545); however, the CR in the adult hyperoxia group was significantly smaller than the adult normoxia group (P12w, 1.44 ± 0.03 mm, 1.50 ± 0.03 mm, p = 0.003). In conclusion, hyperoxia was demonstrated to induce myopic shift both in neonatal and adult mice, which was attributed to the change in the CR rather than the AL. Elucidation of the mechanisms of hyperoxia and the application of this result to humans should be carried out in future studies.

IMI - Myopia Control Reports Overview and Introduction

With the growing prevalence of myopia, already at epidemic levels in some countries, there is an urgent need for new management approaches. However, with the increasing number of research publications on the topic of myopia control, there is also a clear necessity for agreement and guidance on key issues, including on how myopia should be defined and how interventions, validated by well-conducted clinical trials, should be appropriately and ethically applied. The International Myopia Institute (IMI) reports the critical review and synthesis of the research evidence to date, from animal models, genetics, clinical studies, and randomized controlled trials, by more than 85 multidisciplinary experts in the field, as the basis for the recommendations contained therein. As background to the need for myopia control, the risk factors for myopia onset and progression are reviewed. The seven generated reports are summarized: (1) Defining and Classifying Myopia, (2) Experimental Models of Emmetropization and Myopia, (3) Myopia Genetics, (4) Interventions for Myopia Onset and Progression, (5) Clinical Myopia Control Trials and Instrumentation, (6) Industry Guidelines and Ethical Considerations for Myopia Control, and (7) Clinical Myopia Management Guidelines.

Association between birth weight and refractive error in adulthood: a Mendelian randomisation study

BACKGROUND

Pathological myopia is one of the leading causes of blindness globally. Lower birth weight (BW) within the normal range has been reported to increase the risk of myopia, although findings conflict. We sought to estimate the causal effect of BW on refractive error using Mendelian randomisation (MR), under the assumption of a linear relationship.

METHODS

Genetic variants associated with BW were identified from meta-analysis of a genome-wide association study (GWAS) for self-reported BW in 162 039 UK Biobank participants and a published Early Growth Genetics (EGG) consortium GWAS (n=26 836). We performed a one-sample MR analysis in 39 658 unrelated, adult UK Biobank participants (independent of the GWAS sample) using an allele score for BW as instrumental variable. A two-sample MR sensitivity analysis and conventional ordinary least squares (OLS) regression analyses were also undertaken.

RESULTS

In OLS analysis, BW showed a small, positive association with refractive error: +0.04 D per SD increase in BW (95% CI 0.02 to 0.07; p=0.002). The one-sample MR-estimated causal effect of BW on refractive error was higher, at +0.28 D per SD increase in BW (95% CI 0.05 to 0.52, p=0.02). A two-sample MR analysis provided similar causal effect estimates, with minimal evidence of directional pleiotropy.

CONCLUSIONS

Our study suggests lower BW within the normal range is causally associated with a more myopic refractive error. However, the impact of the causal effect was modest (range 1.00 D covering approximately 95% of the population).

Growth curves of myopia-related parameters to clinically monitor the refractive development in Chinese schoolchildren

PURPOSE

To produce a clinical model for the prediction of myopia development based on the creation of percentile curves of axial length in school-aged children from Wuhan in central China.

METHODS

Data of 12,554 children (6054 girls and 6500 boys) were collected and analyzed for the generation of the axial length growth curves. A second data set with 226 children and three yearly successive measurements was used to verify the predictive power of the axial length growth percentile curves. Percentile curves were calculated for both gender groups and four age groups (6, 9, 12, and 15 years). The second data set was used to verify the efficacy of identifying the refractive error of the children using the axial length curves, based on their spherical refractive error from the third visit.

RESULTS

From 6 to 15 years of age, all percentiles showed a growth trend in axial length, except for the percentiles below the first quartile, which appear to stabilize after the age of 12 (- 0.10; 95%CI, - 0.36-0.16; P = 0.23 for girls; - 0.16; 95%CI, - 0.70-0.39; P = 0.34 for boys); however, the growth continued for the remaining 75% of cases. The second data set showed that the likelihood of suffering high myopia (spherical refractive error ≤- 5.00D) during adolescent years increased when axial length values were above the first quartile, for both genders.

CONCLUSIONS

The data from the current study provide a tool to observe the annual growth rates of axial length and can be considered as an approach to predict the refractive development at school ages.

Refractive Trend of Stage 3 Retinopathy of Prematurity

PURPOSE

To analyze the yearly refractive trend in patients with stage 3 retinopathy of prematurity (ROP) over a 7-year time period.

METHODS

This was a retrospective review of 70 eyes of 35 patients with stage 3 ROP.

RESULTS

Of the 70 eyes, 46 received laser ablation and 24 did not. There was a similar distribution between zone II and zone III disease in both groups (P = .87). The average final refraction in the laser group was -0.83 diopters (D) in comparison to +1.61 D in the no laser group. The final refractive change was -3.55 D in the laser group and -0.25 D in the no laser group. A greater myopic shift was observed in the first 2 years of life than between years 2 and 7 in both groups.

CONCLUSIONS

Infants who underwent laser treatment for stage 3 ROP tended to have higher myopia than those with stage 3 ROP who did not require treatment. [J Pediatr Ophthalmol Strabismus. 2018;55(6):403-406.].

The diluted atropine for inhibition of myopia progression in Korean children

AIM

To evaluate the efficacy and safety of three different concentrations of diluted atropine for the control of myopia in Korean children, and to assess the risk factors associated with rapid myopia progression.

METHODS

A total of 285 children, with refractive errors within the range of -6 diopters (D) between 5 and 14 years of age were included. After using 0.01%, or 0.025%, or 0.05% atropine, for about 1y, changes in refraction, axial lengths and frequency of adverse events were analyzed. Logistic regression analyses were performed to evaluate the risk factors associated with rapid myopia progression.

RESULTS

The changes in the mean spherical equivalent values were -0.134 D/mo in the before atropine group, -0.070 D/mo in the 0.01% atropine group, -0.047 D/mo in the 0.025% atropine group, and -0.019 D/mo in the 0.05% atropine group, with significant differences between the groups (P<0.001). The axial elongation was 0.046 mm/mo, 0.037 mm/mo, 0.025 mm/mo, and 0.019 mm/mo respectively, with significant differences between the groups (P=0.003). The incidence of photophobia and near vision difficulty was not different among the three atropine groups (P=0.425 and P=0.356, respectively). Multivariate logistic regression analyses showed that only highly myopic parents were a significant predictive factor of rapid myopia progression in Korean children (odds ratio, 8.155; 95% confidence interval, 3.626-18.342; P<0.001).

CONCLUSION

Treatment with 0.01%, 0.025% and 0.05% atropine solution inhibits myopia progression in Korean children in a dose-dependent manner. Children with highly myopic parents preferentially shows a rapid myopia progression rate.

Association of low birth weight with myopic refractive error and lower visual acuity in adulthood: results from the population-based Gutenberg Health Study (GHS)

Purpose

Low birth weight (BW) is linked to impaired organ development in childhood, including altered ocular morphological and functional development. The aim of this study was to evaluate whether low BW has long-term effects on visual acuity and refraction in adulthood.

Methods

The Gutenberg Health Study is a population-based, observational cohort study in Germany, including 15 010 participants aged between 35 and 74 years. These participants were divided into three different BW groups (low: <2500 g; normal: between 2500 and 4000 g; and high: >4000 g). Best-corrected visual acuity and objective refraction were examined. We used multivariable linear regression models with adjustment for age, sex, socioeconomic status and self-reported glaucoma, age-related macular degeneration, corneal disease and cataract to assess associations between BW and the main outcome measures, best-corrected visual acuity, spherical equivalent and astigmatism.

Results

Overall, 8369 participants reported their BW. In a multivariable analysis, an association for low BW with spherical equivalent (B=−0.28 per dioptre, P=0.005) and best-corrected visual acuity (B=0.02 logarithm of the minimum angle of resolution, P=0.006) compared with normal BW was observed. For participants with high BW, an association was observed with spherical equivalent (B=0.29 per dioptre, P<0.001), while none with visual acuity.

Conclusions

Our data demonstrated that low BW is linked to visual acuity and refractive long-term outcomes long after childhood. Individuals with low BW are more likely to have lower visual acuity and a higher myopic refractive error in adulthood. Adults with high BW are more likely to have a more hyperopic refractive error.

Ocular Findings in Low Birthweight and Premature Babies in the First Year: Do We Need to Screen?

Purpose

There is no standardized approach for the ophthalmic care follow-up of children screened for retinopathy of prematurity (ROP). The authors report the ocular findings at 12 months in preterm and low birthweight babies screened for ROP over a 5-year period (1998–2003).

Methods

The case notes of 211 babies were retrospectively reviewed for birth details, maternal details, presence of ROP, and findings at follow-up screening which included visual acuity, refraction at 12 months, presence of squint, and any other ocular problems.

Results

At 1 year follow-up, 16.6% of ROP positive children failed a screening visit because of squint (6.66%), refractive error (6.66%), and optic nerve abnormalities (3.33%). At 1 year follow-up, 10% of ROP negative children had failed a screening visit because of squint (3.75 %), refractive error (3.75%), and other pathology (2.5%).

Conclusions

The authors recommend screening all babies with ROP at 12 months to identify amblyogenic factors such as squint and refractive error. Parents of infants who do not develop ROP should be advised of the increased risk of visual problems in their children and to have their child examined in the preschool period.

Short-term Refractive Effects of Propranolol Hydrochloride Prophylaxis on Retinopathy of Prematurity in Very Preterm Newborns

PURPOSE

Retinopathy of prematurity (ROP) is one of the major problems of surviving premature infants with several ophthalmic morbidities such as increased risk of refractive errors, strabismus, and cortical visual impairment. Use of propranolol hydrochloride (PH) for the prevention of ROP is a new promising treatment modality. However, long-term effects are still to be defined. In our study, we aimed to investigate the short-term refractive effects of PH used for ROP prophylaxis in very preterm newborns.

METHODS

This is a prospective, randomized, double-blind, placebo-controlled study. Very preterm newborns with a birthweight less than or equal to 1500 g and/or born prior to 32 gestational weeks were included in the study. The subjects were randomly divided into two groups: control group (CG, n = 37) given placebo and PH group (PHG, n = 34) given PH starting from 4 weeks after birth (27.1 ± 2.1 day). PHG patients received PH therapy for about 1 month (25.7 ± 7.8 day). Anthropometric measurements including weight, length, and head circumference were recorded before PH treatment (at birth) and during eye control (at corrected age). Cycloplegic refraction values were measured by retinoscopy at corrected age (CG: 10.3 ± 4.3 months, PHG: 11.4 ± 4.8 months).

RESULTS

Anthropometric measurements including gestational age, weight, length, and head circumference were similar at birth and corrected age in both groups. The mean level of spherical refraction was significantly less hyperopic in the PHG than in the CG (CG: 1.37 ± 1.40 D, PHG: 0.37 ± 1.44 D) (p = 0.005).

CONCLUSION

PH may lead to myopic shift by affecting the beta-adrenergic receptors in the choroid or ciliary body of the developing eye. Long-term refractive follow-up is required in order to elucidate the effects of PH on emmetropization process of these very preterm infants.

Refractive state and optical compositions of preterm children with and without retinopathy of prematurity in the first 6 years of life

This study aimed to investigate the refractive state and optical compositions of preterm children with and without mild retinopathy of prematurity (ROP) and explore the influence of prematurity and mild ROP on the development of refractive state and optical compositions.Preterm children who received fundus screening were recruited, and divided into ROP group and non-ROP group. Term children matched in age were also recruited as controls. Several correspondence indicators were measured before and after ciliary muscle paralysis with 1% cyclopentanone.A total of 250 eyes from 126 patients were included for analysis. The incidence of myopia was the highest in ROP group. The incidence of hyperopia was the highest in control group. The incidence of astigmatism was the highest in ROP group. The corneal astigmatism and mean astigmatism in ROP group and non-ROP group were significantly higher than in control group. Corneal refraction in ROP was markedly higher than in non-ROP group and control group; corneal curvature in ROP group increased significantly as compared with non-ROP group and control group (P < .05). The axial eye length in ROP group and non-ROP group reduced significantly as compared with control group (P < .05). Gestational age had negative relationships with corneal astigmatism (P = .019) and astigmatism (P = .001) and positive relationship with axial eye length (P = .005). Birth weight had negative relationships with corneal astigmatism (P = .001), astigmatism (P < .001), corneal refraction (P = .001), and corneal curvature (P = .001) and positive relationships with axial eye length (P = .001) and spherical equivalent refraction (P = .039). The incidence of myopia increased and that of hyperopia reduced in children over age. In children aged 3 to 4 years, the anterior chamber depth, lens thickness, vitreous thickness, and axial eye length significantly increased as compared with those aged 5 years (P < .05); the vitreous thickness and axial eye length in children aged 5 years increased significantly as compared with those aged 6 years (P < .05).This study shows that preterm children with and without mild ROP are more likely to develop myopia and astigmatism, and low birth weight, prematurity, and ROP may simultaneously affect the development of optical compositions, leading to myopia and astigmatism.

Association of birth weight with corneal power in early adolescence: Results from the National Health and Nutrition Examination Survey (NHANES) 1999-2008

Purpose

To analyze the effect of birth weight on ocular morphology, refraction and visual function in early adolescents aged 12–15 years.

Material and methods

We conducted a secondary data analysis using the public use files from the National Health and Nutrition Examination Survey of the period from 1999 to 2008. Study participants aged 12 to 15 years were included with data on birth weight and ophthalmic parameters including presenting distance visual acuity, objective refraction and keratometry. Visual acuity, sphere, astigmatism in power vectors J₀ and J₄₅, corneal power and corneal astigmatism were evaluated for an association with birth weight. Linear and logistic regression with adjustment for age, sex, ethnicity, survey cycle and birth weight as independent variable were calculated.

Results

Linear regression analysis revealed an association between corneal power and birth weight (per 100g: beta = -0.04, p<0.001) in the univariate analysis, and in the model adjusted for age, sex, ethnicity and NHANES survey cycle (per 100g: beta = -0.04, p<0.001). A lower birth weight was associated with higher corneal power. We found no evidence for an association of visual acuity, sphere, spherical equivalent, J₀-vector and J₄₅-vector of astigmatism, corneal J₀- or corneal J₄₅-vector with birth weight.

Conclusion

Our data demonstrate that low BW is linked to alterations in keratometric power even in early adolescents aged 12–15 years whereas visual acuity and refractive error showed no association.

Axial Length and Ocular Development of Premature Infants without ROP

Purpose

To investigate the ocular parameters of premature infants without ROP at gestational age (GA) more than 28 weeks and their relationship with growth parameters.

Methods

76 preterm infants without ROP and 65 term infants were involved to undergo portable slit lamp, RetCam3, ultrasonic A-scan biometry, and cycloplegic streak examination at their 40 weeks' postconceptional ages (PCA). Ocular parameters of infants' right eye and growth parameters were used for analysis.

Results

All the infants were examined at 40 weeks' PCA. No significant difference was found between male and female in axial length of preterm infants (p = 0.993) and term infants (p = 0.591). Significant differences were found in axial length (AL), anterior chamber depth (ACD), lens thickness (LT), and vitreous depth (VD) between preterm and term infants. No significant correlation was found between AL and spherical equivalent in preterm infants' group. In preterm group, AL was significantly correlated with gestational age (GA), birth weight (BW), and head circumference (HC).

Conclusions

Preterm infants had shorter AL, shallow ACD, thicker LT, and thinner VD compared to term infants. Refractive error in preterm infants at GA between 28 to 37 weeks was not related to axial length. Among all the growth parameters of preterm infants, GA, BW, and HC had effect on axial length.

Long-term evaluation of refractive changes in eyes of preterm children: a 6-year follow-up study

PURPOSE

To investigate the longitudinal changes in refractive errors in preterm children with and without retinopathy of prematurity (ROP) in the first 6 years of life.

METHODS

We included 226 preterm children with a gestational age of ≤34 weeks: 222 eyes with no ROP, 73 eyes with mild ROP and 145 eyes with severe ROP. Longitudinal cycloplegic refraction data were collected initially and yearly thereafter until 6 years of age.

RESULTS

Eyes in the severe ROP group showed an increase in myopia values between the 1- and 3-year examinations (p = 0.005), with little change thereafter. However, the mild/no ROP group demonstrated a nonsignificant increasing myopia values throughout the 6-year follow-up (p = 0.073). Both the mild/no ROP and severe ROP groups were found to have increasing mean astigmatism values with increasing age, albeit nonsignificantly (p = 0.418, p = 0.384, respectively). Likewise, the stable mean values of anisometropia increased nonsignificantly during the first 6 years of life in both the mild/no ROP and severe ROP groups (p = 0.246, p = 0.073, respectively). Severe ROP group had higher values regarding myopia, astigmatism, and anisometropia parameters than the mild/no ROP group for all ages during the follow-up.

CONCLUSIONS

Preterm children with severe ROP should be closely monitored, and also those with mild/no ROP should be carefully followed up for not overlooking possible increases in refractive conditions.

The neural retina in retinopathy of prematurity

Retinopathy of prematurity (ROP) is a neurovascular disease that affects prematurely born infants and is known to have significant long term effects on vision. We conducted the studies described herein not only to learn more about vision but also about the pathogenesis of ROP. The coincidence of ROP onset and rapid developmental elongation of the rod photoreceptor outer segments motivated us to consider the role of the rods in this disease. We used noninvasive electroretinographic (ERG), psychophysical, and retinal imaging procedures to study the function and structure of the neurosensory retina. Rod photoreceptor and post-receptor responses are significantly altered years after the preterm days during which ROP is an active disease. The alterations include persistent rod dysfunction, and evidence of compensatory remodeling of the post-receptor retina is found in ERG responses to full-field stimuli and in psychophysical thresholds that probe small retinal regions. In the central retina, both Mild and Severe ROP delay maturation of parafoveal scotopic thresholds and are associated with attenuation of cone mediated multifocal ERG responses, significant thickening of post-receptor retinal laminae, and dysmorphic cone photoreceptors. These results have implications for vision and control of eye growth and refractive development and suggest future research directions. These results also lead to a proposal for noninvasive management using light that may add to the currently invasive therapeutic armamentarium against ROP.

CHOROIDAL THICKNESS IN INFANTS WITH RETINOPATHY OF PREMATURITY

PURPOSE

To evaluate choroidal thickness in premature infants and its relationship with stage of retinopathy of prematurity (ROP) using spectral domain optical coherence tomography (SD-OCT).

METHODS

Spectral domain optical coherence tomography imaging for measuring subfoveal choroidal thickness was performed for 80 premature infants. Subfoveal choroidal thickness was defined as the distance from the hyperreflective line of the outermost retinal pigment epithelium (RPE) to the innermost hyperreflective line of the choroidoscleral junction. Each measurement was performed at the central fovea (CF) and 0.75 mm to 1.5 mm nasal (N1 and N2) and temporal (T1 and T2) to the fovea. Subfoveal choroidal thickness and grading of cystoid macular edema (CME) were analyzed statistically.

RESULTS

Choroidal thickness of CF was found to be significantly greater than nasal (N1 and N2) and temporal (T1 and T2) choroidal thickness (P < 0.05). There was no significant relationship between stage of ROP and nasal (N1 and N2) choroidal thickness (P = 0.057, P = 0.282, respectively). However, CF and temporal (T1 and T2) choroidal thickness was found to be significantly lower at a higher stage of ROP (P = 0.005, P = 0.01 and P = 0.001). No significant relationship was found between subfoveal choroidal thickness and the grades of cystoid macular edema (P > 0.05). The choroidal thickness of CF was found to be correlated with birth weight (r = 0.267, P = 0.017) but not birth week (r = 0.140, P = 0.217). Maximum stage of ROP was found to be negatively correlated with choroidal thickness, at N1, T1, and T2 (r < -0.250, P < 0.02).

CONCLUSION

The subfoveal choroid in premature infants can be effectively evaluated using a portable SD-OCT device. Choroidal thickness gets thinner with the severity of ROP and the decrease is more prominent at the central and temporal location. Cystoid macular edema is not correlated with choroidal thickness in premature infants.

Long-term refractive status of preterm infants from singleton and multiple pregnancies. J Matern Fetal Neonatal Med 2016;30:2276-2280. [PMID: 27718778 DOI: 10.1080/14767058.2016.1245719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

OBJECTIVE

To study the effect of plurality on refractive status in former preterm infants at age 8-12 years.

METHODS

Refraction was compared in singletons and multiples, in very low birth weight infants (VLBW, <1500 g) at age 6 months and 8-12 years. Preterm infants were compared with a group of term infants.

RESULTS

Thirty-seven of 104 (36%) VLBW infants were multiples. Comparison of refraction between singletons and multiples revealed no difference at age 6 months, while at age 8-12 years, multiples had significantly more refractive errors (singletons 28% versus multiples 54% p = 0.01), particularly myopia. In preterms, refractive status at age 6 months and multiple birth were significant predictors of refraction at 8-12 years, while birth weight (BW) and retinopathy of prematurity (ROP) were not predictive. Refractive errors were significantly more common in preterms (37%) than in term-born children (14%) (p = 0.0002). Overall, refraction moved from predominantly hyperopic at 6 months to normal or myopic at age 8-12 years in preterm.

CONCLUSIONS

Multiple gestation in preterms is associated with increased risk for refractive errors, particularly myopia in childhood. Refraction in preterms during childhood progresses from hyperopia to myopia. Former preterms have more refractive errors than children born at term-born children.

Review of effects of anti-VEGF treatment on refractive error

To examine the effect of anti-vascular endothelial growth factor (anti-VEGF) agents on refractive error in the setting of retinopathy of prematurity (ROP) through a review of the literature, a PubMed search was performed of appropriate search terms, and the results of all relevant studies were extracted and compiled. Eleven relevant articles were identified in the literature, totaling 466 eyes, treated with varied anti-VEGF agents (bevacizumab, ranibizumab, and aflibercept) with mean spherical equivalent refractions ranging from +0.75 D to −3.57 D, with prevalence of high myopia ranging from 0 to 35%. Anti-VEGF monotherapy for ROP leads to low levels of myopia, and there may be a differential effect of specific anti-VEGF agents utilized on refractive outcomes.

Retinal, visual, and refractive development in retinopathy of prematurity

The pivotal role of the neurosensory retina in retinopathy of prematurity (ROP) disease processes has been amply demonstrated in rat models. We have hypothesized that analogous cellular processes are operative in human ROP and have evaluated these presumptions in a series on non-invasive investigations of the photoreceptor and post-receptor peripheral and central retina in infants and children. Key results are slowed kinetics of phototransduction and deficits in photoreceptor sensitivity that persist years after ROP has completely resolved based on clinical criteria. On the other hand, deficits in post-receptor sensitivity are present in infancy regardless of the severity of the ROP but are not present in older children if the ROP was so mild that it never required treatment and resolved without a clinical trace. Accompanying the persistent deficits in photoreceptor sensitivity, there is increased receptive field size and thickening of the post-receptor retinal laminae in the peripheral retina of ROP subjects. In the late maturing central retina, which mediates visual acuity, attenuation of multifocal electroretinogram activity in the post-receptor retina led us to the discovery of a shallow foveal pit and significant thickening of the post-receptor retinal laminae in the macular region; this is most likely due to failure of the normal centrifugal movement of the post-receptor cells during foveal development. As for refractive development, myopia, at times high, is more common in ROP subjects than in control subjects, in accord with refractive findings in other populations of former preterms. This information about the neurosensory retina enhances understanding of vision in patients with a history of ROP, and taken as a whole, raises the possibility that the neurosensory retina is a target for therapeutic intervention.

Evaluation of structural contributors in myopic eyes of preterm and full-term children

PURPOSE

We conducted a cross-sectional study to test the hypothesis that the structural contributions to myopia in preterm and full-term born children are different.

METHODS

In this study, 93 children ranging from ages 2 to 13 who had myopia ≥ -3 diopters in at least one eye were examined with A-scans. The following data was collected and analyzed: history of birth, refractive error (RE), cornea thickness (CT) and average corneal curvature (AVK), depth of anterior chamber (ACD), lens thickness (LT), and axial length (AL) of the eye.

RESULTS

Eyes were tested and categorized into four groups: myopic eyes in full-term children (group 1), myopic eyes in premature children (group 2), non-myopic eyes in full-term children (group 3), and non-myopic eyes in preterm children (group 4). The RE were similar between group 1 and group2, and between group 3 and group 4. Myopic eyes in group 2 had higher AVK as compared to group 3; 45.4 ± 0.4 D vs. 43.5 ± 0.7 D, p = 0.008. The ACD in group 2 was shallower than that in group 1 (2.5 ± 0.5 vs. 3.2 ± 0.3, p = 0.01). The LT measurements in group 2 were thicker than those in group 1 (mean LT = 4.9 ± 1.0 vs 4.1 ± 0.3 mm, p = 0.001, respectively). Finally, AL of myopic eyes in group 1 was longer than that of group 2, p = 0.01.

CONCLUSION

These results suggest that increased axial length plays an important role in myopia in full-term children, whereas corneal curvature and lens thickness are major contributors to myopia in preterm children.

Comparison of Refractive Error Changes in Retinopathy of Prematurity Patients Treated with Diode and Red Lasers

Aim: To compare refractive error changes in retinopathy of prematurity (ROP) patients treated with diode and red lasers. Methods: A randomized double-masked clinical trial was performed, and infants with threshold or prethreshold type 1 ROP were assigned to red or diode laser groups. Gestational age, birth weight, pretreatment cycloplegic refraction, time of treatment, disease stage, zone and disease severity were recorded. Patients received either red or diode laser treatment and were regularly followed up for retina assessment and refraction. The information at month 12 of corrected age was considered for comparison. Results: One hundred and fifty eyes of 75 infants were enrolled in the study. Seventy-four eyes received diode and 76 red laser therapy. The mean gestational age and birth weight of the infants were 28.6 ± 3.2 weeks and 1,441 ± 491 g, respectively. The mean baseline refractive error was +2.3 ± 1.7 dpt. Posttreatment refraction showed a significant myopic shift (mean 2.6 ± 2.0 dpt) with significant difference between the two groups (p < 0.001). There was a greater myopic shift among children with zone I and diode laser treatment (mean 6.00 dpt) and a lesser shift among children with zone II and red laser treatment (mean 1.12 dpt). The linear regression model, using the generalized estimating equation method, showed that the type of laser used has a significant effect on myopic shift even after adjustment for other variables. Conclusion: Myopic shift in laser-treated ROP patients is related to the type of laser used and the involved zone. Red laser seems to cause less myopic shift than diode laser, and those with zone I involvement have a greater myopic shift than those with ROP in zone II.

Eye growth in term- and preterm-born eyes modeled from magnetic resonance images

PURPOSE

We generated a model of eye growth and tested it against an eye known to develop abnormally, one with a history of retinopathy of prematurity (ROP).

METHODS

We reviewed extant magnetic resonance images (MRIs) from term and preterm-born patients for suitable images (n = 129). We binned subjects for analysis based upon postmenstrual age at birth (in weeks) and ROP history ("Term" ≥ 37, "Premature" ≤ 32 with no ROP, "ROP" ≤ 32 with ROP). We measured the axial positions and curvatures of the cornea, anterior and posterior lens, and inner retinal surface. We fit anterior chamber depth (ACD), posterior segment depth (PSD), axial length (AL), and corneal and lenticular curvatures with logistic growth curves that we then evaluated for significant differences. We also measured the length of rays from the centroid to the surface of the eye at 5° intervals, and described the length versus age relationship of each ray, L(ray)(x), using the same logistic growth curve. We determined the rate of ray elongation, E(ray)(x), from L(ray)dy/dx. Then, we estimated the scleral growth that accounted for E(ray)(x), G(x), at every age and position.

RESULTS

Relative to Term, development of ACD, PSD, AL, and corneal and lenticular curvatures was delayed in ROP eyes, but not Premature eyes. In Term infants, G(x) was fast and predominantly equatorial; in age-matched ROP eyes, maximal G(x) was offset by approximately 90°.

CONCLUSIONS

We produced a model of normal eye growth in term-born subjects. Relative to normal, the ROP eye is characterized by delayed, abnormal growth.

Refractive Error in Patients with Retinopathy of Prematurity after Laser Photocoagulation or Bevacizumab Monotherapy

PURPOSE

To evaluate the refractive development of premature infants with retinopathy of prematurity (ROP) after treatment with laser photocoagulation or intravitreal injection of bevacizumab (IVB).

METHODS

The medical records of patients with ROP treated between 2003 and 2012 who underwent yearly follow-ups were retrospectively reviewed. Patients with residual ROP abnormalities were excluded. The cycloplegic refraction at 3 years of age, assessed using an autorefractometer, was recorded.

RESULTS

In total, 54 eyes from 54 patients were enrolled. Patients were divided into 4 groups: group 1, including 14 eyes of 14 patients treated with laser therapy; group 2, 15 eyes of 15 patients treated with IVB; group 3, 13 eyes of 13 patients with non-type 1 ROP under conservative follow-up, and group 4, 12 eyes of 12 premature patients without ROP. The mean spherical equivalent at 3 years of age was -1.71 ± 1.27 dpt in group 1, -1.53 ± 2.20 dpt in group 2, 0.63 ± 1.37 dpt in group 3, and 0.41 ± 1.95 dpt in group 4. The mean refractive error differed significantly among the 4 groups (p < 0.001). Patients in groups 1 and 2 were more prone to myopia compared with those in groups 3 and 4. Furthermore, patients with type 1 ROP treated by laser photocoagulation (group 1) and those treated by IVB (group 2) had similar refraction (p = 1).

CONCLUSIONS

The results of this study suggest that treatment-demanding ROP eyes are susceptible to more severe myopia with age compared with eyes without ROP or those with spontaneously regressed ROP. In addition, the myopic status between laser and IVB treatment did not differ statistically.

Refraction and visual acuity in a national Danish cohort of 4-year-old children of extremely preterm delivery

PURPOSE

A recent threefold increase in laser treatment for advanced retinopathy of prematurity (ROP) triggered a nationwide preschool ophthalmic and developmental status among extremely preterm survivors. Here, we discuss refraction and visual acuity.

METHODS

Survivors (n = 178) from a national birth cohort (February 2004 to March 2006) of gestational age <28 weeks (PT) and 56 full-term (FT) controls attended for evaluation at age 4 years. Cycloplegic refraction and keratometry were achieved by Retinomax autokeratorefractor and visual acuities by symbol recognition (HOTV, logMAR).

RESULTS

The refractive distribution presented a myopic tail (4.5%) and a hyperopic tail (11.9% ≥+2.5 D) as special preterm features, and corneas were more curved. Astigmatism and anisometropia were only marginally increased, and visual acuities were generally good. Best-corrected binocular median logMAR visual acuity was 0.1 in FT and 0.2 in PT, in Snellen equivalents 0.8 and 0.63. Snellen acuity ≤0.5 occurred across the ROP subgroups, but mainly in those with at least ROP stage 3. Two children had low vision.

CONCLUSIONS

The overall fair outcome for refraction and function is in accordance with other recent northern Europe experience. The results differ in particular from the poorer ophthalmic outcomes reported in the pioneer US treatment studies (cryotherapy for ROP and ETROP). The diode laser ablations (n = 32) appeared effective in our series; except one child, all treated subjects had good or fair social vision at the age of 4 years.

Association of birth parameters with refractive status in a sample of caucasian children aged 4-17 years

Purpose. To investigate the association of birth parameters with refractive status in different age groups of Caucasian children. Materials and Methods. This cross-sectional study included 564 eyes of 282 children aged 4 to 17 years. All children underwent complete ophthalmologic examination. The children were divided into three groups according to their refractive status (emmetropia,myopia, and hyperopia), ages (4-7, 8-9, 10-12, and 13-17), and appropriateness for gestational age, respectively. Results. The mean age of the children was 9.2 ± 2.8 (age range 4-17 years). The mean spheric equivalent was +0.3 ± 1.7 (range: (-10.0)-(+10.0) diopters). The mean birth weight and gestational age were 2681.1 ± 930.8 grams (750-5000 grams) and 37.2 ± 3.7 weeks (25-42 weeks). According to multinominal logistic regression analysis, children with myopia were more likely to have higher birth weights than emmetropic children (OR: 1.0, 95% CI: 1.000-1.001, and P = 0.028). The hypermetropes were found to be significantly small for gestational age between 13 and 17 years of age. Conclusion. Birth weight and appropriateness for gestational age as birth parameters may have an impact on development of all types of refractive errors. The hypermetropic children tended to be small for gestational age.

Impact of retinopathy of prematurity on ocular structures and visual functions

The preterm baby may develop ophthalmic sequelae which can be due to prematurity per se, due to retinopathy of prematurity (ROP) or due to neurological damage. Focusing on the former two, we discuss how in high-income countries the risk of sight-threatening ROP is largely confined to babies <1000 g birth weight (BW), whereas in low-income or middle-income countries babies exceeding 2500 g BW can be blinded. The effects of prematurity and ROP are presented as regional and global estimates of acute-phase ROP and the consequent mild/moderate and severe visual impairment. We discuss sequelae and how they affect the eye and its shape, strabismus and finally consider their impact on visual functions, including visual acuity, the visual field, colour vision and contrast sensitivity.