Utility of retinoscopy to examine peripheral refraction

Purpose: This study explored whether retinoscopy (RET) provides comparable results of relative peripheral refraction (RPR) to open–field autorefractometry (AR) in myopic subjects.Methods: Peripheral refraction was measured in 20 myopic and 20 control adult subjects. Both central and peripheral refraction (20° nasal and temporal eccentricity) were measured using RET and open-field AR. Differences in the median central spherical equivalent (SE), median RPR, and median J45/J180 power vectors between the RET and AR techniques were analyzed. Moreover, Bland – Altman plots were used to assess the agreement between RET and AR methods for RPR measurements in MG. Results: For MG, the median RPR values were positive (hyperopic shift), and no significant differences were observed between the RET and AR techniques with respect to RPR measurement. In addition, we did not observe any significant differences in the RPR values between the nasal and temporal eccentricities for either the RET or AR technique for myopic subjects. There was also a significant correlation and agreement between the RET and AR technique for RPR measurements. With respect to central refraction, the median SE was slightly more positive for the RET than for the AR technique. Inside the CG, we also found significant correlation between the RET and AR technique for RPR measurements, and we observed a myopic shift in peripheral eccentricities. Conclusion: Our results show that retinoscopy may be a useful tool for objective measurements of RPR in myopic subjects and may be used interchangeably with the open-field AR method in everyday clinical practice. (AU)

Peripheral Ganglion Cell Complex Thickness and Retinal Microvasculature in Myopia Using Wide-Field Swept-Source OCT.

Purpose: This study aims to investigate the impact of axial elongation on ganglion cell complex thickness (GCCT) and retinal capillary density (CD) using wide-field swept-source optical coherence tomography angiography. Methods: A retrospective cross-sectional analysis was conducted involving 506 eyes. Fovea-centered scans were obtained to assess the subregional GCCT and capillary density across the whole retina, the superficial capillary plexus (SCP), and deep capillary plexus (DCP) among three groups: normal control, high myopia (HM) eyes with axial length < 28 mm, and HM eyes with axial length > 28 mm. Regional variations (central vs. peripheral, quadrants difference [superior, inferior, nasal, and temporal]) were analyzed. Results: In HM eyes with axial length > 28 mm, GCCT and retinal CD exhibit a general decline in most regions (P < 0.05). In HM eyes with axial length < 28 mm, significant reductions were observed specifically in peripheral regions, as in the GCCT beyond the 3 × 3 mm2 area and CD in the 9-12 mm whole retina, 9-12 mm superior SCP, and 6-12 mm DCP (P < 0.05). Maximum GCCT and retinal CD reduction with axial elongation was observed in subregions beyond 6 × 6  mm2. Conclusions: GCCT beyond the 3 × 3 mm2 area and peripheral retinal CD beyond the 6 × 6  mm2 area were more susceptible to axial elongation and are thereby deserving of particular attention. Translational Relevance: It is necessary to evaluate different regions during the clinical assessment of the effect of myopia on the fundus and pay close attention to the peripheral retina.

The effect of cycloplegia in the accuracy of autorefraction, keratometry and axial length using the Myopia Master.

BACKGROUND: Assessing refractive errors under cycloplegia is recommended for paediatric patients; however, this may not always be feasible. In these situations, refraction has to rely on measurements made under active accommodation which may increase measurements variability and error. Therefore, evaluating the accuracy and precision of non-cycloplegic refraction and biometric measurements is clinically relevant. The Myopia Master, a novel instrument combining autorefraction and biometry, is designed for monitoring refractive error and ocular biometry in myopia management. This study assessed its repeatability and agreement for autorefraction and biometric measurements pre- and post-cycloplegia. METHODS: A prospective cross-sectional study evaluated a cohort of 96 paediatric patients that underwent ophthalmologic examination. An optometrist performed two repeated measurements of autorefraction and biometry pre- and post-cycloplegia. Test-retest repeatability (TRT) was assessed as differences between consecutive measurements and agreement as differences between post- and pre-cycloplegia measurements, for spherical equivalent (SE), refractive and keratometric J0/J45 astigmatic components, mean keratometry (Km) and axial length (AL). RESULTS: Cycloplegia significantly improved the SE repeatability (TRT, pre-cyclo: 0.65 D, post-cyclo: 0.31 D). SE measurements were more repeatable in myopes and emmetropes compared to hyperopes. Keratometry (Km) repeatability did not change with cycloplegia (TRT, pre-cyclo: 0.25 D, post-cyclo:0.27 D) and AL repeatability improved marginally (TRT, pre-cyclo: 0.14 mm, post-cyclo: 0.09 mm). Regarding pre- and post-cycloplegia agreement, SE became more positive by + 0.79 D, varying with refractive error. Myopic eyes showed a mean difference of + 0.31 D, while hyperopes differed by + 1.57 D. Mean keratometry, refractive and keratometric J0/J45 and AL showed no clinically significant differences. CONCLUSIONS: Refractive error measurements, using the Myopia Master were 2.5x less precise pre-cycloplegia than post-cycloplegia. Accuracy of pre-cycloplegic refractive error measurements was often larger than the clinically significant threshold (0.25 D) and was refractive error dependent. The higher precision compared to autorefraction measurements, pre- and post-cycloplegia agreement and refractive error independence of AL measurements emphasize the superiority of AL in refractive error monitoring.

Lamina Cribrosa Configurations in Highly Myopic and Non-Highly Myopic Eyes: The Beijing Eye Study.

Purpose: The purpose of this study was to examine characteristics of lamina cribrosa (LC) configuration in highly myopic (HM) eyes. Methods: Participants from the Beijing Eye Study 2011, free of optic nerve or retinal diseases, were randomly selected to examine LC depth (LCD) and LC tilt (LCT) using three-dimensional optical coherent tomography images of the optic nerve head (ONH). LCD and LCT were measured as the distance and angle between the LC plane with two reference planes, including the Bruch's membrane opening (BMO) plane and the peripapillary sclera (PPS) plane, respectively. Each parameter was measured in both horizontal and vertical B-scans. Results: The study included 685 individuals (685 eyes) aged 59.6 ± 7.7 years, including 72 HM eyes and 613 non-HM eyes. LCD measurements showed no significant differences between HM eyes and non-HM eyes in both horizontal (LCD-BMO = 421.83 ± 107.86 µm for HM eyes vs. 447.24 ± 104.94 µm for non-HM eyes, P = 0.18; and LCD-PPS = 406.39 ± 127.69 µm vs. 394.00 ± 101.64 µm, P = 1.00) and vertical directions (LCD-BMO = 435.78 ± 101.29 µm vs. 450.97 ± 106.54 µm, P = 0.70; and LCD-PPS = 401.62 ± 109.9 µm vs. 379.85 ± 110.35 µm, P = 0.35). However, the LCT was significantly more negative (tilted) in HM eyes than in non-HM eyes horizontally (LCT-BMO = -4.38 ± 5.94 degrees vs. -0.04 ± 5.86 degrees, P < 0.001; and LCT-PPS = -3.16 ± 5.23 degrees vs. -0.94 ± 4.71 degrees, P = 0.003), but not vertically (P = 1.00). Conclusions: Although LCD did not differ significantly between HM and non-HM eyes, LCT was more negative in HM eyes, suggesting that the temporal or inferior side of the LC was closer to the reference plane. These findings provide insights into morphological and structural changes in the LC and ONH between HM and non-HM eyes.

Knowledge, attitude, and practice of non-ophthalmic medical staff toward myopia-related fundus lesions.

This study assessed the knowledge, attitude, and practice (KAP) of non-ophthalmic medical staff towards myopia-related fundus lesions. This multicenter, cross-sectional study enrolled non-ophthalmic medical staff of Suining City between January and May 2023 using a self-designed questionnaire. A total of 505 (93.19%) valid questionnaires were included. Their mean KAP scores were 8.10 ± 2.32 (range: 0-12), 20.27 ± 2.68 (range: 0-24), and 17.77 ± 5.04 (range: 0-28), respectively. Structural equation modeling indicated that knowledge has a positive effect on attitude (ß = 0.307, P < 0.001), and attitude has a positive effect on practice (ß = 0.604, P < 0.001). Moreover, a higher degree of myopia exhibited a positive effect on knowledge (ß = 0.510, P < 0.001). Nurses and other medical staff showed a negative effect on knowledge (ß = - 0.706, P < 0.001) compared to doctors. Working in secondary and tertiary public hospitals, as well as private hospitals, demonstrated a negative effect on practice (ß = - 1.963, P < 0.001) compared to those working in primary hospitals. Non-ophthalmic medical staff exhibited moderate knowledge, positive attitudes, and moderate practices toward myopia-related fundus lesions. The degree of myopia, doctors vs. other medical staff, and the hospital level influence the KAP of non-ophthalmic medical staff.

Diagnosis of forme fruste keratoconus with scheimpflug photography in Ghanaian patients.

AIM: This study aimed to differentiate moderate to high myopic astigmatism from forme fruste keratoconus using Pentacam parameters and develop a predictive model for early keratoconus detection. METHODS: We retrospectively analysed 196 eyes from 105 patients and compared Pentacam variables between myopic astigmatism (156 eyes) and forme fruste keratoconus (40 eyes) groups. Receiver operating characteristic curve analysis was used to determine the optimal cut-off values, and a logistic regression model was used to refine the diagnostic accuracy. RESULTS: Statistically significant differences were observed in most Pentacam variables between the groups (p < 0.05). Parameters such as the Index of Surface Variance (ISV), Keratoconus Index (KI), Belin/Ambrosio Deviation Display (BAD_D) and Back Elevation of the Thinnest Corneal Locale (B.Ele.Th) demonstrated promising discriminatory abilities, with BAD_D exhibiting the highest Area under the Curve. The logistic regression model achieved high sensitivity (92.5%), specificity (96.8%), accuracy (95.9%), and positive predictive value (88.1%). CONCLUSION: The simultaneous evaluation of BAD_D, ISV, B.Ele.Th, and KI aids in identifying forme fruste keratoconus cases. Optimal cut-off points demonstrate acceptable sensitivity and specificity, emphasizing their clinical utility pending further refinement and validation across diverse demographics.

Survey on pattern of myopia in school children in Hangzhou after the COVID-19 pandemic: a school-based vision screening study.

BACKGROUND: Myopia is a major health issue around the world. Myopia in children has increased significantly during the COVID-19 pandemic in China, but reports are scarce on the prevalence of myopia following the pandemic. This study collected vision screening data of school children in China for five consecutive years to observe the changes in myopia after the pandemic and compare the observed prevalence of myopia before and after the pandemic. METHODS: A school-based vision screening study used stratified samplings to collect the vision screening data in school children aged 6-13 from 45 primary schools in Hangzhou. Vision screening data including uncorrected visual acuity(UCVA) and spherical equivalent refraction(SER). Calculating the mean of SER and the prevalence of myopia and hyperopia from 2019 to 2023. RESULTS: A total of 79,068 screening results (158,136 eyes) were included in the analysis. A substantial myopic shift (approximately -0.30 diopters [D] on average) was found in 2020 and 2021 compared with 2019 in all age groups and a substantial myopic shift (approximately 0.4 D on average) was found in 2022 compared with 2021. A slight myopic shift (approximately -0.14 D on average) was found in 2023 compared with 2022. The prevalence of myopia in all age groups was the highest for five years in 2020 or 2021, which was 31.3% for 6-year-olds, 43.0% for 7-year-olds, and 53.7% for 8-year-olds. A positive change in the prevalence rate of myopia was found at 6 years old (0.59%, 0.12%, 0.36%, 0.25%, p < 0.001). The change in prevalence rate in myopia was shifted slightly in children aged 10-13 years. Children aged 8 to 13 years had a slight increase in myopia prevalence from 2022 to 2023. The prevalence of hyperopia was low and stable in all grade groups, ranging from 0.7% to 2.2% over five years. CONCLUSION: Myopia in children has increased rapidly during the COVID-19 pandemic. After the pandemic, the prevalence of myopia in children gradually decreased temporarily and then rebounded. Myopic shift was more apparent in younger children. Myopic shift in children may be related to the reduction of outdoor time, less light, and near work habits, and further research is needed.

[Analysis of myopia status and related factors among primary school students in a certain district of Beijing City in 2022].

Objective: To analyze the current situation of myopia and its related factors among primary school students in a certain district of Beijing City in 2022, and provide a basis for the risk assessment of myopia among primary school students. Method: In June 2022, a cluster sampling method was used to include 376 third-grade students from a primary school in a certain district of Beijing. A questionnaire survey was conducted to collect basic information about students, including eye usage habits, reading and writing postures, and parents' myopia conditions. The examination of students' distant visual acuity and refractive status was performed. A multivariate logistic regression model was used to analyze the related factors of myopia occurrence. Results: The age of 376 primary school students was (8.87±0.417) years old, with 48.40% (182) being male. A total of 196 myopia cases were identified, with a myopia rate of 52.13%. The results of the multivariate logistic regression model analysis showed that students who sometimes read while lying down (OR=2.003, 95%CI: 1.128-3.555), often read while lying down (OR=18.853, 95%CI: 4.512-78.778), had outdoor activity time less than 120 minutes per day (OR=4.937, 95%CI: 2.4464-9.892), were engaged in indoor break activities (OR=4.995, 95%CI: 2.773-8.996), performed eye exercises less than once per day (OR=8.710, 95%CI: 4.464-16.995), had a reading distance from the book less than 30 cm (OR=5.098, 95%CI: 2.410-10.787), occasionally maintained a fist distance from the edge of the desk (OR=1.918, 95%CI: 1.086-3.385), and had high school desks and tables (OR=5.325, 95%CI: 1.465-19.359) could have a higher risk of myopia occurrence, compared with those who never read while lying down, had outdoor activity time more than 120 minutes per day, maintained outdoor break activities, performed eye exercises more than once per day, had a reading distance from the book more than 30 cm, always maintained a fist distance from the edge of the desk, and had short school desks and tables. Conclusion: The incidence rate of myopia among primary school students in a certain district of Beijing City. in 2022 is relatively high. The occurrence of myopia is related to insufficient outdoor activity time and poor eye usage habits.

Characteristic features of patients with myopia depending on the expressiveness of anxiety/depression.

OBJECTIVE: Aim: To determine the peculiarities of character traits of patients with myopia at different levels of anxiety and depression. PATIENTS AND METHODS: Materials and Methods: 30 patients with moderate myopia and mild myopic astigmatism in both eyes were examined. The "Kettel Test" was used to study the characteristics of the patient's character, and the Hospital Anxiety and Depression Scale was used to assess the levels of anxiety and depression. All examined patients were divided into 3 groups: the 1st group with a normal level of anxiety, the 2nd group with subclinical anxiety/depression, the 3rd grоup with clinically pronounced anxiety/depression. Mathematical processing of the research results was carried out using the methods of mathematical statistics. RESULTS: Results: Characteristic features of patients with myopia include conservatism, restraint, subordination, anxiety, developed imagination and high self-control. In half of people with myopia, anxiety/depression is subclinically determined, and in a third - clinically expressed anxiety/depression is observed. In the absence of anxiety in patients with myopia, the main character traits were conservatism, restraint, subordination, sufficient normative behavior, high self-control, and self-confidence; in the presence of subclinical anxiety - sufficient self-control and normative behavior, sociability, developed imagination, conservatism; with clinically expressed anxiety and depression - developed imagination, anxiety, significant normative behavior, conservatism, restraint, subordination. CONCLUSION: Conclusions: Studying the characteristic features of patients with myopia is necessary to clarify the peculiarities of the formation of the internal picture of the disease, the etiopathogenesis of the formation of nosogenies due to this pathology, and the development of individual psycho-corrective programs for such patients.

Bi-exponential description for different forms of refractive development.

It was recently established that the axial power, the refractive power required by the eye for a sharp retinal image in an eye of a certain axial length, and the total refractive power of the eye may both be described by a bi-exponential function as a function of age (Rozema, 2023). Inspired by this result, this work explores whether these bi-exponential functions are able to simulate the various known courses of refractive development described in the literature, such as instant emmetropization, persistent hypermetropia, developing hypermetropia, myopia, instant homeostasis, modulated development, or emmetropizing hypermetropes. Moreover, the equations can be adjusted to match the refractive development of school-age myopia and pseudophakia up to the age of 20 years. All of these courses closely resemble those reported in the previous literature while simultaneously providing estimates for the underlying changes in axial and whole eye power.

Comparison of axial length and anterior segment parameters of patients with myopia measured using 2 fourier-domain optical coherent biometry devices.

BACKGROUND: This study assessed the agreement of ocular parameters of patients with myopia measured using Colombo intraocular lens (IOL) 2 and IOLMaster 700. METHODS: Eighty patients (male, 22; average age, 29.14 ± 7.36 years) with myopia (159 eyes) were included in this study in May 2023. The participants' axial length (AXL), central corneal thickness (CCT), lens thickness (LT), white-to-white distance (WTW), front flat (K1), steep (K2), mean (Km) corneal keratometry, astigmatism (Astig), J0 vector, and J45 vector were measured using the IOLMaster 700 and Colombo IOL 2. The measurements from both devices were compared using the generalized estimating equation, correlation analysis, and Bland-Altman plots. RESULTS: With the Colombo IOL 2, lower values for K2 and J0 (odds ratio [OR] = 0.587, p = 0.033; OR = 0.779, p < 0.0001, respectively), and larger values for WTW, Astig, and J45 (OR = 1.277, OR = 1.482, OR = 1.1, all p < 0.0001) were obtained. All ocular measurements by both instruments showed positive correlations, with AXL demonstrating the strongest correlation (r = 0.9996, p < 0.0001). The intraclass correlation coefficients for AXL and CCT measured by both instruments was 0.999 and 0.988 (both p < 0.0001), and Bland-Altman plot showed 95% limits of agreement (LoA) of -0.078 to 0.11 mm and - 9.989 to 13.486 µm, respectively. The maximum absolute 95% LoA for LT, WTW, K1, K2, and J0 were relatively high, achieving 0.829 mm, 0.717 mm, 0.983 D, 0.948 D, and 0.632 D, respectively. CONCLUSIONS: In young patients with myopia, CCT and AXL measurements obtained with the Colombo IOL 2 and IOLMaster 700 were comparable. However, WTW, LT, corneal refractive power, and astigmatism values could not be used interchangeably in clinical practice.

Evaluating the quality and reliability of YouTube videos on myopia: a video content analysis.

PURPOSE: To evaluate the quality and reliability of YouTube videos as an educational resource about myopia. METHODS: The videos were identified by searching YouTube with the keywords 'myopia' and 'nearsightedness', using the website's default search settings. The number of views, likes, dislikes, view ratio, source of the upload, country of origin, video type, and described treatment techniques were assessed. Each video was evaluated using the DISCERN, Journal of the American Medical Association (JAMA), Ensuring Quality Information for Patients (EQIP), Health On the Net Code of Conduct Certification (HONcode), and the Global Quality Score (GQS) scales. RESULTS: A total of 112 videos were included. The classification of videos by source indicated that the top three contributors were health channels (30 videos [26.8%]), physicians (24 videos [21.4%]), and academic centers (19 videos [16.9%]). Most of these videos originated from the United States (74 videos [66.1%]) and focused on the pathophysiology (n = 89, 79.4%) and the treatment (n = 77, 68.7%) of myopia. Statistical comparisons among the groups of video sources showed no significant difference in the mean DISCERN score (p = 0.102). However, significant differences were noted in the JAMA (p = 0.011), GQS (p = 0.009), HONcode (p = 0.011), and EQIP (p = 0.002) scores. CONCLUSIONS: This study underscored the variability in the quality and reliability of YouTube videos related to myopia, with most content ranging from 'weak to moderate' quality based on the DISCERN and GQS scales, yet appearing to be 'excellent' according to the HONcode and EQIP scales. Videos uploaded by physicians generally exhibited higher standards, highlighting the importance of expert involvement in online health information dissemination. Given the potential risks of accessing incorrect medical data that can affect the decision-making processes of patients, caution should be exercised when using online content as a source of information.

Efficacy of pars plana vitrectomy combined with internal limiting membrane peeling and gas tamponade for treating myopic foveoschisis: a meta-analysis.

OBJECTIVE: This study aimed to evaluate and explore the efficacy of pars plana vitrectomy (PPV) combined with internal limiting membrane (ILM) peeling and gas tamponade in treating myopic foveoschisis (MF) through a meta-analysis. METHODS: Systematic searches were conducted on the PubMed, Web of Science and National Library of Medicine (NLM) English-language databases and the China National Knowledge Infrastructure (CNKI) and Wanfang Chinese-language databases. The primary outcome measures were postoperative best-corrected visual acuity (BCVA) and central foveal thickness (CFT), with the secondary outcome being the postoperative complication rate. Data analysis was performed using RevMan5.3 software. RESULTS: A total of 10 studies involving 234 eyes were included. The meta-analysis results showed the following: (1) The average postoperative BCVA improved compared with preoperative levels, with an average improvement in the logarithm of the minimum angle of resolution of 0.40, a statistically significant difference (95% CI: -0.44, - 0.20, p < 0.001); (2) the rate of postoperative BCVA improvement was 77% (95% CI: 65%, 90%, p < 0.001); (3) the postoperative CFT significantly decreased by an average of 385.92 µm, a statistically significant difference (95% CI: -437.85, - 333.98, p < 0.001); (4) the postoperative macular retinal complete reattachment rate was 90% (95% CI: 83%, 97%, p < 0.001); (5) the most common postoperative complication was a cataract, with an incidence of 55.9%. CONCLUSION: Using PPV combined with ILM peeling and gas tamponade to treat MF is reliable.

Diurnal gene expression patterns in retina and choroid distinguish myopia progression from myopia onset.

The world-wide prevalence of myopia (nearsightedness) is increasing, but its pathogenesis is incompletely understood. Among many putative mechanisms, laboratory and clinical findings have implicated circadian biology in the etiology of myopia. Consistent with a circadian hypothesis, we recently reported a marked variability in diurnal patterns of gene expression in two crucial tissues controlling post-natal refractive development - the retina and choroid-at the onset of form-deprivation myopia in chick, a widely studied and validated model. To extend these observations, we assayed gene expression by RNA-Seq in retina and choroid during the progression of established unilateral form-deprivation myopia of chick. We assayed gene expression every 4 hours during a single day from myopic and contralateral control eyes. Retinal and choroidal gene expression in myopic vs. control eyes during myopia progression differed strikingly at discrete times during the day. Very few differentially expressed genes occurred at more than one time in either tissue during progressing myopia. Similarly, Gene Set Enrichment Analysis pathways varied markedly by time during the day. Some of the differentially expressed genes in progressing myopia coincided with candidate genes for human myopia, but only partially corresponded with genes previously identified at myopia onset. Considering other laboratory findings and human genetics and epidemiology, these results further link circadian biology to the pathogenesis of myopia; but they also point to important mechanistic differences between the onset of myopia and the progression of established myopia. Future laboratory and clinical investigations should systematically incorporate circadian mechanisms in studying the etiology of myopia and in seeking more effective treatments to normalize eye growth in children.

Testing the homogeneity of odds ratio across strata for combined bilateral and unilateral data.

Bilateral and unilateral combined data are commonly involved in clinical trials or observational studies designed to test the treatment effectiveness on paired organs or bodily parts within individual subjects. It is essential to examine if the treatment effect is consistent across different subgroups such as age, gender, or disease severity for understanding how the treatment works for various patient populations. In this paper, we propose three large-sample homogeneity tests of odds ratio in the stratified randomization setting using correlated combined data. Our simulation results show that the score test exhibits robust empirical type I error control and demonstrates strong power characteristics compared to other methods proposed. We apply the proposed tests to real-world datasets of acute otitis media and myopia to illustrate their practical application and utility.

Wide-field optical eye models for emmetropic and myopic eyes.

Ocular wavefront aberrations are used to describe retinal image formation in the study and modeling of foveal and peripheral visual functions and visual development. However, classical eye models generate aberration structures that generally do not resemble those of actual eyes, and simplifications such as rotationally symmetric and coaxial surfaces limit the usefulness of many modern eye models. Drawing on wide-field ocular wavefront aberrations measured previously by five laboratories, 28 emmetropic (-0.50 to +0.50 D) and 20 myopic (-1.50 to -4.50 D) individual optical eye models were reverse-engineered by optical design ray-tracing software. This involved an error function that manipulated 27 anatomical parameters, such as curvatures, asphericities, thicknesses, tilts, and translations-constrained within anatomical limits-to drive the output aberrations of each model to agree with the input (measured) aberrations. From those resultant anatomical parameters, three representative eye models were also defined: an ideal emmetropic eye with minimal aberrations (0.00 D), as well as a typical emmetropic eye (-0.02 D) and myopic eye (-2.75 D). The cohorts and individual models are presented and evaluated in terms of output aberrations and established population expectations, such as Seidel aberration theory and ocular chromatic aberrations. Presented applications of the models include the effect of dual focus contact lenses on peripheral optical quality, the comparison of ophthalmic correction modalities, and the projection of object space across the retina during accommodation.

Automated eyeball volume measurement based on CT images using neural network-based segmentation and simple estimation.

With the increase in the dependency on digital devices, the incidence of myopia, a precursor of various ocular diseases, has risen significantly. Because myopia and eyeball volume are related, myopia progression can be monitored through eyeball volume estimation. However, existing methods are limited because the eyeball shape is disregarded during estimation. We propose an automated eyeball volume estimation method from computed tomography images that incorporates prior knowledge of the actual eyeball shape. This study involves data preprocessing, image segmentation, and volume estimation steps, which include the truncated cone formula and integral equation. We obtained eyeball image masks using U-Net, HFCN, DeepLab v3 +, SegNet, and HardNet-MSEG. Data from 200 subjects were used for volume estimation, and manually extracted eyeball volumes were used for validation. U-Net outperformed among the segmentation models, and the proposed volume estimation method outperformed comparative methods on all evaluation metrics, with a correlation coefficient of 0.819, mean absolute error of 0.640, and mean squared error of 0.554. The proposed method surpasses existing methods, provides an accurate eyeball volume estimation for monitoring the progression of myopia, and could potentially aid in the diagnosis of ocular diseases. It could be extended to volume estimation of other ocular structures.

Comparison of clinical outcomes of a corneal wavefront- and topography-guided platforms for laser in situ keratomileusis on virgin eyes: an expanded cohort study.

PURPOSE: To compare the clinical outcomes of myopiacorrected with corneal-wavefront-guided (CWG) laser in situ keratomileusis (LASIK) with AMARIS 1050S (SCHWIND eye-tech-solutions GmbH & Co. KG) and corneal-topography-guided (CTG) LASIK with WaveLight EX500 (Alcon Laboratories, Fort Worth, TX). METHODS: In this prospective, pseudo-randomized expanded cohort study, a total of 266 patients were subjected to binocular LASIK surgery, either with WaveLight EX500 (WaveLight group) or Amaris 1050S (AMARIS group) platforms. Data related to right eyes were selected for analysis. Corneal higher-order aberration (HOA) was selected as the primary endpoint; while visual acuity and refraction were the secondary endpoints. All the endpoints were assessed at 3 months postoperatively. RESULTS: There were 134 eyes in the AMARIS group and 132 eyes in the WaveLight group. After 3 months of postoperative follow-up, spherical and coma aberrations were significantly lower (P < 0.05) in the WaveLight group (spherical aberration: - 0.104 ± 0.199 µm; coma aberration: - 0.117 ± 0.202 µm) in comparison with the AMARIS group (spherical aberrations: 0.254 ± 0.146 µm; coma aberrations: 0.316 ± 0.297 µm). In the AMARIS group, 96.3% of the eyes achieved an uncorrected distance visual acuity (UDVA) of 20/20 while in the WaveLight group, 96.2% of the eyes achieved an UDVA of 20/20. Furthermore, the mean postoperative manifest refraction spherical equivalent (MRSE) was - 0.02 ± 0.28 in the AMARIS group and - 0.05 ± 0.21 in the WaveLight group (P = 0.34). CONCLUSIONS: Both WaveLight EX500 and Amaris 1050S LASIK showed excellent refractive and visual outcomes. In addition, the WaveLight group showed minimal spherical and coma aberrations when compared to the AMARIS group.

Impact of defocus incorporated multiple segments (DIMS) spectacle lenses for myopia control on quality of life of the children: a qualitative study.

OBJECTIVE: To assess the impact of DIMS (defocus incorporated multiple segments) spectacle lenses on the quality of life of children using it. METHODS: Separate in-depth interviews were conducted with children using DIMS as a myopia control strategy for at least 1 month and their parents based on prepared guides. The recorded audio of the interviews was transcribed, and the significant data points were coded using a hybrid approach, that is, both the inductive and deductive coding methods were used to identify themes. The generated codes were further grouped, categorised and finally fitted as per relevance into the subdomains of the four domains of the WHO Quality of Life-Brief framework, namely the domains of social relationships, physical, psychological and environmental health. RESULTS: A total of 29 interviews were conducted, 15 with children (mean age: 12.47±2.13 years) and 14 with parents. Thematic analysis was done and a total of 63 codes were generated with 2, 16, 17 and 28 codes aligning to the domains of social relationships, environmental, psychological and physical health, respectively. Most parents did not notice any change in their child's visual behaviour, yet children did experience symptoms such as peripheral blurred vision, eyestrain, headache, haloes and more during the adaptation period. High-cost, scratch-prone nature and difficulty in procurement were a few concerns raised by parents. CONCLUSIONS: Participants were satisfied with most of the facets of social relationships, physical and psychological health domains. However, a few facets such as quality, accessibility and finance of the environmental health domain need improvement.

Correlation in retinal thickness and macular retina plus choroidal microcirculation in pediatric myopia.

To analyze the relationship in retinal thickness, macula retina and choroidal microcirculation in pediatric patients with myopia. Pediatric patients with high myopia (high myopia group, n = 30, 60 eyes) and pediatric patients with low to moderate myopia (low myopia group, n = 30, 60 eyes) admitted to our hospital from January 2021 to January 2022 were randomly selected as the study subjects. Retinal thickness, the blood density of retina, and the blood density of the choroid were collected in each area of the macula by taking optical coherence tomography (OCT) and OCT angiography (OCTA). Pearson correlation analysis was conducted to compare the results from the 2 groups. Outer retinal thickness showed a weak positive correlation with Superficial vascular complex flow density (SVD) and deep vascular complex flow density (DVD) (P < .05), but no significant correlation with choroidal capillary density (P > .05); inner retinal thickness showed a weak positive correlation with SVD and DVD (P < .05), but no significant correlation with choroidal capillary density (P > .05). In pediatric patients with myopia, there is a positive correlation between the blood flow density of macular retina and retinal thickness, and the retinal thickness will become thinner with increasing myopia.