Mean Axial Length Research Articles

Effect of Vitamin D Supplement on Axial Length of Myopes

Myopia is triggered on by excessive axial elongation. Vitamin D deficiency somehow relevant to myopia genic visual cues. Objectives: To compare the level of vitamin D 25(OH)D in myopes and emmetropes and to access the effect of vitamin D 25(OH)D supplements in different degrees of myopia and compare the axial length. Methods: A Randomize Controlled Trail Study was conducted in Madina Teaching Hospital, Faisalabad on 60 subjects from September 2022 to April 2023 with age ranges 15-25 years. All were subjected to following examinations; BCVA, slit-lamp examination, A-scan and vitamin D level. The sample was randomly divided into two groups through Non-probability Purposive Sampling Technique. Group 1 was emmetropic, whereas group 2 exhibits various degrees of myopia. Group 2 takes up supplemental vitamin D followed by 1 month. Results: Mean age was 20.82 years ± 2.32. Out of the total 60 subjects, 24 (40%) were male while 36 (60%) were female.47 subjects (78.3%) reported having less than 4 hours of outdoor exposure while 13 subjects (21%) reported having more than 4 hours. Mean axial length 21.97 ± .80 and 22.66 ± 1.29 of emmetropes (p=0.008) while myopes 24.30 ± .91 and 24.13 ± 1.04 at baseline and after one month respectively (p=0.023). Mean vitamin D level was 18.36 ± 1.37and 17.13 ± 1.35 of emmetropes (p=0.00) while 15.63 ± 1.54and 16.90 ± 2.75 at baseline and after one month respectively (p=0.00). Conclusions: There was a significant association between low levels of vitamin D and the development of myopia in emmetropes and vitamin D supplementation can help to prevent the axial length elongation of myopes

Distribution and Characteristics of Ocular Biometric Parameters among a Chinese Population: A Hospital-Based Study.

This study aimed to describe the distribution and characteristics of ocular biometric parameters among a large Chinese population. This retrospective cross-sectional study included 146,748 subjects whose ocular biometric parameters were measured at the ophthalmology clinic of West China Hospital, Sichuan University, and recorded in the hospital database. Ocular biometric parameters, including axial length, anterior chamber depth, corneal keratometry, and keratometric astigmatism, were recorded. Only monocular data for each subject were analyzed to avoid bias. Valid data from 85,770 subjects (43,552 females and 42,218 males) aged 3-114years were included in this study. The mean axial length, mean anterior chamber depth, average corneal keratometry, and mean keratometric astigmatism were 24.61mm, 3.30mm, 43.76D, and 1.19D, respectively. The stratification of the ocular parameters by age and gender showed significant inter-gender and inter-age differences. Analysis of a large population of subjects in western China aged 3-114years showed that the distribution and characteristics of ocular biometric parameters, including axial length, anterior chamber depth, corneal keratometry, and keratometric astigmatism, differed by age and gender. This study is the first to describe ocular biometric parameters in subjects aged > 100years.

Evaluation and comparison of ocular biometric parameters obtained with Tomey OA-2000 in silicone oil-filled aphakic eyes

PurposeTo evaluate a new non-contact instrument (OA-2000) measuring the ocular biometry parameters of silicone oil (SO)-filled aphakic eyes, as compared with IOLMaster 700.MethodsForty SO-filled aphakic eyes of 40 patients were enrolled in this cross-sectional clinical trial. The axial length (AL), central corneal thickness (CCT), keratometry ((flattest keratometry) Kf and (steep keratometry, 90° apart from Kf) Ks), and axis of the Kf (Ax1) were measured with OA-2000 and IOLMaster 700. The coefficient of variation (CoV) was calculated to assess the repeatability. The correlation was evaluated by the Pearson coefficient. Bland-Altman analysis and paired t test were used to analyze the agreements and differences of parameters measured by the two devices, respectively.ResultsThe mean AL obtained with the OA-2000 was 23.57 ± 0.93 mm (range: 21.50 to 25.68 mm), and that obtained with the IOLMaster 700 was 23.69 ± 0.94 mm (range: 21.85 to 25.86 mm), resulting in a mean offset of 0.124 ± 0.125 mm (p < 0.001). The mean offset of CCT measured by OA-2000 and IOLMaster 700 was 14.6 ± 7.5 μm (p < 0.001). However, the Kf, Ks and Ax1 values from the two devices were comparable (p > 0.05). All the measured parameters of the two devices showed strong linear correlations (all r ≥ 0.966). The Bland-Altman analysis showed a narrow 95% limits of agreement (LoA) of Kf, Ks and AL, but 95%LoA of CCT and Ax1 was wide, which were − 29.3 ~ 0.1 μm and-25.9 ~ 30.7°respectively. The CoVs of the biometric parameters obtained with OA-2000 were lower than 1%.ConclusionIn SO-filled aphakic eyes, the ocular parameters (including AL, Kf, Ks, Ax1, and CCT) measured by the OA-2000 and IOLMaster 700 had a good correlation. Two devices had an excellent agreement on ocular biometric measurements of Kf, Ks and AL. The OA-2000 provided excellent repeatability of ocular parameters in SO-filled aphakic eyes.

Intraocular lens formula calculation in pediatric eyes: Do we have an answer? A retrospective comparison between Sanders-Retzlaff-Kraff II and Barret's formula.

The ideal formula for intraocular lens (IOL) power calculation following cataract surgery in pediatric eyes till date has no answer. We compared the predictability of the Sanders-Retzlaff-Kraff (SRK) II and the Barrett Universal (BU) II formula and the effect of axial length, keratometry, and age. This was a retrospective analysis of children who were under eight years of age and who underwent cataract surgery with IOL implantation under general anesthesia between September 2018 and July 2019. The prediction error of SRK II formula was calculated by subtracting the target refraction and the actual postoperative spherical equivalent. Preoperative biometry values were used to calculate the IOL power using the BU II formula with the same target refraction that was used in SRK II. The predicted spherical equivalent of the BU II formula was then back-calculated using the SRK II formula with the IOL power obtained with the BU II formula. The prediction errors of the two formulae were compared for statistical significance. Seventy-two eyes of 39 patients were included in the study. The mean age at surgery was 3.8 ± 2 years. The mean axial length was 22.1 ± 1.5 mm, and the mean keratometry was 44.7 ± 1.7 D. The group with an axial length >24 mm showed a significant and strong positive correlation (r = 0.93, P = 0) on comparison mean absolute prediction errors using the SRK II formula. There was a strong negative correlation between the mean prediction error in the overall keratometry group using the BU II formula (r = -0.72, P < 0.000). There was no significant correlation between age and refractive accuracy using the two formulae in any of the subgroups of age. There is no perfect answer to an ideal formula for IOL calculation in children. IOL formulae need to be chosen keeping in mind the varying ocular parameters.

Effectiveness of 0.01% atropine in anisomyopic children

Purpose: To investigate the change in ocular parameters of anisomyopic children treated with 0.01% atropine. Methods: This retrospective study analyzed the data of anisomyopic children who underwent comprehensive examination at a tertiary eye center in India. Anisomyopic subjects (difference of ≥1.00 D) of age 6–12 years who were treated with 0.01% atropine or prescribed regular single vision spectacle and had follow-ups of more than 1 year were included. Results: Data from 52 subjects were included. No difference was observed in the mean rate of change of spherical equivalent (SE) of more myopic eyes between 0.01% atropine (−0.56 D; 95% confidence interval [CI]: −0.82, −0.30) and single vision lens wearers (−0.59 D; 95% CI: −0.80, −0.37; P = 0.88). Similarly, insignificant change in the mean SE of less myopic eyes was noted between the groups (0.01% atropine group, −0.62 D; 95% CI: −0.88, −0.36 vs. single vision spectacle wearer group, −0.76 D; 95% CI: −1.00, −0.52; P = 0.43). None of the ocular biometric parameters showed any difference between the two groups. Though anisomyopic cohort treated with 0.01% atropine revealed a significant correlation between the rate of change of mean SE and axial length in both eyes (more myopic eyes, r = −0.58; P = 0.001 and less myopic eyes, r = −0.82; P < 0.001) compared to single vision spectacle wearer group, the change was not significant. Conclusion: Administration of 0.01% atropine had minimal effect on reducing the rate of myopia progression in anisomyopic eyes.

Relatively anterior lens position in primary angle-closure glaucoma eyes with long axial length.

To evaluate the refractive status and ocular biometric parameters in primary angle-closure glaucoma (PACG) eyes with different axial lengths (ALs). In total, 742 Chinese PACG subjects with complete ophthalmic examinations were enrolled. The refractive status was categorized as myopia (spherical equivalent [SE] ≤-0.5 D), emmetropia (-0.5 D < SE < +0.5 D), and hyperopia (SE ≥+0.5 D), whereas the AL was divided into short (AL <22.5 mm), regular (22.5 ≤ AL <23.5 mm), and long (AL ≥23.5 mm). The refractive status and ocular biometric parameters were compared among different AL groups. The mean AL of the PACG eyes was 22.53 ± 0.84 mm (range: 19.68-25.57 mm). The refractive status was significantly different among different AL groups (P < 0.001). Also, 92.6% of hyperopic PACG eyes showed AL <23.5 mm, and 19.0% of myopic PACG eyes showed AL ≥23.5 mm. The SE showed significant differences among different AL groups only in the hyperopic subjects (P = 0.012). The AL was significantly longer in myopic eyes (P < 0.001). The PACG eyes with longer AL exhibited lower keratometry, longer central anterior chamber depth and corneal diameter, and lens position and relative lens position closer to the anterior (P < 0.001). Axial hyperopia was common in PACG eyes, and axial myopia was not uncommon. Relatively anterior lens position could explain the occurrence of PACG in the eyes with long AL.

RISK FACTORS FOR DEVELOPMENT OF PHACOMORPHIC GLAUCOMA IN MATURE CATARACT - A HOSPITAL BASED STUDY, JHANSI

Aim:To study the roles of axial length and anterior chamber depth as risk factors for the development of phacomorphic glaucoma in eyes with mature cataract. Material and Methods: This is a prospective case-control study done in the year 2023 at Department of Ophthalmology, MLB Medical College, Jhansi. Phacomorphic glaucoma was diagnosed by Intraocular Pressure of more than 21 mmHg, intumescent cataract with signs and symptoms of phacomorphic glaucoma, axial length and anterior chamber depth.All patients examined by slit lamp examination . Results: The Mean Intra ocular pressure of phacomorphic glaucoma was 49±8 mmHg and of mature cataract was 15±6 mmHg. Vision was Light perception in phacomorhic glaucoma and Hand movement observed was mature cataract. The mean axial length was 23.08±0.32mmHg among phacomorphic glaucoma, shorter than mature cataract, where the mean axial length was 23.71±0.78mm. Conclusion:Patients with shorter axial lengths are at increased risk for phacomorphic glaucoma.

Relationship between the main components of the crystalline lens and the anterior chamber depth after cataract formation

PurposeTo assess the relationship between anterior chamber depth (ACD) and lens thickness (LT), as well as its three main components (anterior and posterior cortex and nucleus thickness), in cataractous and non-cataractous eyes, depending on the axial length (AxL).MethodsAnterior and posterior cortex and nucleus thickness of the crystalline lens, ACD, and AxL were measured using optical low-coherence reflectometry in cataractous and non-cataractous eyes. They were also classified into hyperopia, emmetropia, myopia, and high myopia, depending on AxL; thus, eight subgroups were created. A minimum sample size of 44 eyes (of 44 patients) for each group was recruited. Linear models were fitted for the whole sample and each AxL subgroup to assess if there were differences in the relationships between the crystalline lens variables and ACD, including age as a covariate.ResultsThree hundred seventy cataract patients (237 females, 133 males) and 250 non-cataract controls (180 females, 70 males), aged 70.5 ± 9.4 and 41.9 ± 15.5 years, respectively, were recruited. The mean AxL, ACD, and LT for the cataractous and non-cataractous eyes were 23.90 ± 2.05, 24.11 ± 2.11, 2.64 ± 0.45, and 2.91 ± 0.49, 4.51 ± 0.38, 3.93 ± 0.44 mm, respectively. The inverse relationship of LT, anterior and posterior cortex, and nucleus thickness with ACD was not significantly (p ≥ 0.26) different between cataractous and non-cataractous eyes. Further subclassification of the sample depending on AxL showed that the inverse relationship between the posterior cortex and ACD was no longer significant (p > 0.05) for any non-cataractous AxL group. LT, anterior and posterior cortex, and nucleus thickness was not significantly (p ≥ 0.43) different between cataractous and non-cataractous eyes for the whole sample, and all AxL groups after adjusting for age.ConclusionsThe presence of cataracts does not modify the inverse relationship of the LT, anterior and posterior cortex, and nucleus with ACD. And this relationship does not seem to depend importantly on AxL. Besides, the possible differences in LT, anterior and posterior cortex, and nucleus between cataractous and non-cataractous eyes may not be caused by lens opacification, but possibly by the progressive lens growth due to aging.

Association between axial length and HDL in children: a hospital-based cross-sectional study

BackgroundTo analyze the relationship between axial length and levels of high-density lipoprotein (HDL) cholesterol in children.MethodsA retrospective, hospital-based cross-sectional research with 69 right eyes from 69 children who underwent health examination by Zhejiang Provincial People’s Hospital was carried out. The participants were split into three groups: Group A (axial length < = 23 mm), Group B (axial length 23–24 mm), and Group C (axial length > 24 mm). Demographic epidemiological information, blood biochemical parameters and ophthalmic characteristics including refractive status and ocular geometric parameters were obtained and analyzed.Results69 right eyes from 69 patients (25 males and 44 females) with a median age of 10.00 years old (IQR: 8.00–11.00 years) were included in the study. Within Group A, there were a total of 17 individuals; Group B consisted of 22 individuals; Group C included 30 individuals. The mean axial length of three groups was 22.148(0.360), 23.503(0.342) and 24.770(0.556) mm, respectively (p < 0.0001). The mean HDL levels were significantly different in three groups are 1.824(0.307), 1.485(0.253) and 1.507 (0.265) mmol/L, respectively. By applying a Pearson Coefficient, we evaluated the association between axial length and HDL and discovered that there was a statistically significant (p = 0.00025) and adverse (R = -0.43) association between axial length and HDL.ConclusionsWe concluded from our study that there was a significantly inverse relationship between axial length and the levels of HDL in children.

THE LONG-TERM FOLLOW-UP OF AUTOLOGOUS BLOOD CLOT-ASSISTED LYOPHILIZED HUMAN AMNIOTIC MEMBRANE COVERING TREATMENT UNCLOSED MACULAR HOLE.

The objectives were to assess the long-term morphologic and functional outcome of eyes with unclosed macular hole (MH) in which the internal limiting membrane has been peeled in previous vitrectomy with autologous blood clot-assisted lyophilized human amniotic membrane (LhAM) graft covering. Twelve eyes with MH unclosed in previous surgery were selected and studied. Autologous blood clot-assisted LhAM graft was used to cover the MH in vitrectomy. The main clinical outcomes including best-corrected visual acuity, closure of MH, and the outcome of LhAM graft were recorded. The mean minimum diameter of the MH was 641.7 ± 245.9 µ m and the mean axial length was 27.3 ± 3.50 mm. The LhAM graft was maintained in the former position and all the MH closed in 10 eyes, whereas the graft slipped and the MH unclosed in two eyes. The MH closure rate was 83.3% and the mean best-corrected visual acuity improved significantly from 1.47 ± 0.58 logMAR (Snellen 20/590) preoperatively to 1.17 ± 0.60 logMAR (Snellen 20/296) postoperatively. During 18 to 36 months follow-up, LhAM grafts were attached to the retinal surface in nine eyes, detached from the retinal surface in one eye, dislocated from the fovea in one eye, and inserted into the retina in one eye; and macular atrophy occurred in one eye. Autologous blood clot-assisted LhAM graft covering provided a simple and effective treatment option for unclosed MH and reduce surgical trauma. Although the graft remained on the macular surface for a long time, it did not affect the recovery of MH and postoperative vision.

Myopia Control Efficacy of Spectacle Lenses With Aspherical Lenslets: Results of a 3-Year Follow-Up Study

To investigate myopia control efficacy in children who continued wearing spectacle lenses with highly aspherical lenslets (HAL) or switched from spectacle lenses with slightly aspherical lenslets (SAL) and single-vision spectacle lenses (SVL) to HAL for 1 year after a 2-year myopia control trial. This was a 1-year extension of a randomized clinical trial. Of 54 children who had worn HAL for 2 years, 52 continued wearing HAL (HAL1 group), and of the 53 and 51 children who had originally worn SAL or SVL, 51 and 48 switched to wearing HAL (HAL2 and HAL3 groups) in year 3, respectively. A new SVL (nSVL) group of 56 children was recruited, matched for age, sex, cycloplegic spherical equivalent refraction (SER), and axial length (AL) of the HAL3 group at extension baseline, and used for a comparison of third-year changes. SER and AL were measured every 6 months in year 3. During year 3, the mean (SE) myopia progression in the nSVL group was -0.56 (0.05) diopters (D). Compared with nSVL, the changes in SER were less in HAL1 (-0.38 [0.05] D, P=.02), HAL2 (-0.36 [0.06] D, P=.01), and HAL3 (-0.33 [0.06] D, P=.005). The mean (SE) AL elongation in the nSVL group was 0.28 (0.02) mm. Compared with nSVL, the elongation in AL was less in the HAL1 (0.17 [0.02] mm, P < .001), HAL2 (0.18 [0.02] mm, P < .001), and HAL3 (0.14 [0.02] mm, P < .001) groups. Myopia progression and axial elongation were comparable in all 3 HAL groups (all P > .05) in year 3. Myopia control efficacy has remained in children who wore HAL in the previous 2 years. Children who switched from SAL or SVL to HAL in year 3 had slower myopia progression and axial elongation than that in the control group.

Relationship between choroidal thickness and vascular density in young healthy population

Background and purposeThe purpose is to analyze choroidal vascular density (VD) in healthy individuals and to compare it with choroidal thickness (CT). Materials and methodsCross-sectional study enrolling healthy individuals between 18 and 35 years old of Caucasian race and with an axial length (AL) 21−26 mm. Choroid was imaged with swept-source optical coherence tomography angiography (OCTA) Triton DRI (Topcon) and a macular cube of 6 × 6 mm was obtained. CT values were automatically given by the software. VD values were obtained through codifying colors of the VD map into numbers. Results102 (51 patients) were analyzed. Mean age was 27.32 ± 3.94 years old, mean intraocular pressure was 18.07 ± 2.38 mmHg, and mean AL was 23.71 ± 0.66 mm. CT was higher in the vertical axis and lower when approaching nasal and temporal sides. The highest CT was in superior macula. The highest choroidal VD were in the fovea and in the juxtapapillary region. The lowest choroidal VD were found in superior and inferior macular areas. Moderate inverse correlations between CT and choroidal VD were found in the juxtapapillary and inferior regions. ConclusionsThe choroid has a thickness pattern that differs from retina. Choroidal vessels represent a very high percentage of choroid in the peripapillary region and in the fovea. On the contrary, superior and inferior macula reveals low values of VD.

Outcomes of air versus sulfur hexafluoride tamponade in primary rhegmatogenous retinal detachment in phakic eyes

Purpose To evaluate the outcomes of using air versus sulfur hexafluoride (SF6) gas tamponade in management of primary rhegmatogenous retinal detachment (RRD). Study design Retrospective case-series comparative study. Patients and methods We collected data from 120 patients in three tertiary university hospitals, that were diagnosed as primary RRD due to upper retinal break in the period from January 2021 to November 2022 and had undergone 23-G lens-sparing pars-plana vitrectomy with either air tamponade (Air group) or SF6 gas tamponade (SF6 group) and were followed up for 6 months. We analyzed the final visual outcomes between both groups. Results The mean age of the studied patients was 51±13 years (Air group=60 eyes, SF6 group=60 eyes). The mean axial length in Air group was 26.59±1.84 mm, the mean axial length was 26.46±1.49 mm in SF6 group. Best-corrected visual acuity was improved in both groups at the sixth month. In Air group 18.33% had recurrent RRD, while 10% in SF6 group. No significant difference regarding metamorphopsia was reported. Higher rate for cataract progression was noted among SF6 group. Conclusions Both Air and SF6 gas showed favorable results regarding the final visual outcome. Air is a less expensive tamponade with less timing for postoperative-prone positioning. Cataract progression was higher among SF6 group, however, the incidence of recurrent RRD was lower among SF6 group. Missed break was the primary cause for failed retinal reattachment.

Posterior Corneal Asphericity and the Refractive Outcome after Combined Phacovitrectomy

We assessed the correlation of posterior corneal asphericity and the refractive prediction error of the SRK-T and Barrett II Universal formulas for eyes following phacovitrectomy with peeling of the internal limiting membrane (ILM). We retrospectively analyzed 41 eyes of 41 patients following a combined phacovitrectomy with ILM peeling. Surgeries were performed by one fellowship-trained vitreoretinal surgeon between 2016 and 2021. Of the 41 patients, 41 eyes were included, with all having at least 1 month of postoperative data. Of the 41 eyes, 19 eyes were female (46%) and 22 were male (54%). The average age of the study population was 77.5 ± 10.7 years. The mean axial length (AL) was 22.7 ± 4.6 mm and the mean anterior chamber depth (ACD) was 3 ± 0.8 mm. The mean posterior Q value was - 0.29 ± 0.27. The mean absolute error (MAE) values 1-month postoperatively for the SRK-T and Barrett II Universal formulas were 0.73 and 0.65, respectively. Regression analysis yielded a significant correlation between posterior corneal asphericity and SRK-T MAE (r = 0.35, R2 = 0.12, p < 0.05) only. Posterior corneal surface asphericity is correlated to the refractive error of the SRK-T formula for eyes following phacovitrectomy.

Retrospective Comparison of the Myopia Master and the Lenstar LS900 Axial Length Measurements in Children with Myopia.

This study is a retrospective analysis to compare ocular biometry measurements of axial length in children with myopia using Myopia Master (OCULUS, Wetzlar, Germany) and Lenstar LS900 (HAAG-STREIT AG, Köniz, Switzerland). Axial length measurements obtained with both instruments within a 3-week period were collected retrospectively. Measurements were visualized with a Bland-Altman plot. For statistical evaluation, a paired t-test was applied, and the Pearson correlation coefficient (r) was established. Sixty-one eyes from 31 myopic patients (59% male, 41% female) with a mean age of 11.34 ± 3.25 years (range: 6 - 18 years) were identified. Mean axial length was 24.7 mm (SD 1.29) with the Myopia Master and 24.69 mm (SD 1.30) with the Lenstar LS900 (Pearson correlation: r = 0.9991). The average difference of the axial length measurement between the two biometers was 0.00 064 mm ± 0.056 SD (p = 0.9293). The axial length measured by Myopia Master and Lenstar LS900 did not differ significantly. Thus, previous values obtained with the Lenstar LS900 can be applied to assess myopia progression.

Morphological changes of the retinal layers in the central macula in children with anisometropic amblyopia.

The goal of this study was to evaluate the morphological characteristics of the retinal layers in the central macula in children with anisometropic amblyopia. This comparative, observational, prospective study included 28 patients who were diagnosed with anisometropic amblyopia and 30 age- and sex-matched healthy controls. All children were evaluated using the automatic calculation software system available on spectral-domain optical coherence tomography (SD-OCT) for automated segmentation of the macula. Of the included patients, 18 (64.3%) were male and 10 (35.7%) were female, with a mean age of 10.3±3.4years. Mean spherical equivalent and best-corrected visual acuity (BCVA) were 4.13±1.95 diopters and 0.707±0.36 logMAR, respectively. The mean axial length was significantly lower in amblyopic eyes compared to fellow eyes (22.1±0.34mm vs. 23.3±0.42mm, P<0.0001), and control eyes (22.1±0.34mm vs. 23.1±0.40mm, P<0.0001). The mean thickness of the outer nuclear layer was significantly lower in amblyopic eyes compared to fellow eyes (79.8±11.9μm vs. 86.8±7.9μm, P=0.007), and healthy controls (79.8±11.9μm vs. 87.4±10.5μm, P=0.012). The results of this study showed that there are quantitative differences in retinal microstructures of the macula in eyes with anisometropic amblyopia compared to fellow eyes and healthy controls. These findings suggest that anisometropic amblyopia may result in abnormal development of macular structure in the inner retinal layer. A detailed analysis of retinal layers may be able to provide a guide to the depth of amblyopia and visual prognosis.

Relación entre grosor coroideo y densidad vascular en población joven sana

Background and purposeThe purpose is to analyze choroidal vascular density (VD) in healthy individuals and to compare it with choroidal thickness (CT). Materials and methodsCross-sectional study enrolling healthy individuals between 18 and 35 years old of Caucasian race and with an axial length (AL) 21–26 mm. Choroid was imaged with swept-source optical coherence tomography angiography (OCTA) Triton DRI (Topcon) and a macular cube of 6 mm × 6 mm was obtained. CT values were automatically given by the software. VD values were obtained through codifying colors of the VD map into numbers. ResultsOne hundred and two (51 patients) were analyzed. Mean age was 27.32 ± 3.94 years old, mean intraocular pressure was 18.07 ± 2.38 mmHg, and mean AL was 23.71 ± 0.66 mm. CT was higher in the vertical axis and lower when approaching nasal and temporal sides. The highest CT was in superior macula. The highest choroidal VD were in the fovea and in the juxtapapillary region. The lowest choroidal VD were found in superior and inferior macular areas. Moderate inverse correlations between CT and choroidal VD were found in the juxtapapillary and inferior regions. ConclusionsThe choroid has a thickness pattern that differs from retina. Choroidal vessels represent a very high percentage of choroid in the peripapillary region and in the fovea. On the contrary, superior and inferior macula reveals low values of VD.

Changes of corneal biomechanics in children using orthokeratology and their roles in predicting axial length progression-A prospective 2-year study.

To determine how orthokeratology (ortho-k) affects corneal biomechanical properties in myopia control and whether corneal biomechanical parameters can predict clinical efficacy of ortho-k. A total of 125 children 7-15 years of age using ortho-k lenses were followed in this clinical practice and data of their right eyes were analysed. Corneal biomechanical parameters and most ocular biometry were measured at baseline, 1 week, and at 1, 3, 6, 12, 18 and 24 months. Axial length (AL) was collected every 6 months after baseline measurements. During the 2-year follow up, nine corneal biomechanical parameters, including deformation amplitude maximum (DA), varied between baseline and 1 week (p < 0.05) and stabilized during the rest of wearing period (p > 0.05). The mean AL increased from 25.02 ± 0.84 mm to 25.38 ± 0.81 mm and baseline DA strongly correlated with AL progression (Pearson r=0.37). In the multiple regression models, baseline age, AL and DA were the independent factors for AL progression (R2 : 0.7849, 0.2180 in low and moderate myopes). The area under the receiver operating characteristic curves using the three variables for predicting excessive AL progression (>0.35 mm during 2 years) in low and moderate myopes was 0.902 and 0.698. Corneal biomechanics firstly fluctuated before becoming stable with long-term ortho-k use. Corneal biomechanics was associated with AL progression in children wearing ortho-k lenses. DA combined with age and AL at baseline could predict AL progression in low myopes using ortho-k.

A physical sign of pathological myopia: myopic scleral pit

PurposeMyopic scleral pit (MSP) is a rare physical sign of pathological myopia (PM). The aim of this study was to summarize the clinical characteristics of MSP and analyze its correlation with PM.MethodsEight cases with PM and MSP were enrolled in this study. Comprehensive ophthalmic examinations, including subjective refraction, slit-lamp biomicroscope, intraocular pressure, fundus photographs, A- and B-scan ultrasonography and spectral-domain optical coherence tomography, were performed.ResultsAll the patients had a long history of PM with visual impairment, long axial length, and myopia-related fundus degeneration. Mean axial length was 31.48 ± 2.17 mm. Mean size of MSP was 0.69 ± 0.29 optic disc diameter (PD). Mean logMAR BCVA was 1.21 ± 0.88 logMAR. Spearman correlation analysis showed that the logMAR BCVA had no correlation with the size of pits (P = 0.34). Fundus examination revealed a focal pale concave located in the sclera exposed area of retinal choroid atrophy was found in all cases. OCT showed a deep scleral pit where the retinal choroid was thin or absent, without retinal sensory detachment or sensory defect.ConclusionsThis study identified a rare scleral lesion in all eight individuals with PM, which was termed “myopic scleral pit”. This phenomenon is different from focal choroidal excavation and posterior staphyloma.

Normative data for macular and retinal nerve fibre layer thickness in healthy German children and adolescents using optical coherence tomography.

To establish normative data for macular thickness, macular volume and peripapillary retinal nerve fibre layer (RNFL) thickness using Spectralis® spectral-domain optical coherence tomography (SD-OCT) in healthy German children and adolescents and investigate influencing factors. The cross-sectional study included the right eye of 695 children with at least one complete retinal OCT scan. As part of the LIFE Child study, the children underwent an ophthalmological examination including axial length (AL), spherical equivalent (SE) and OCT measurements. Various questionnaires were answered by the children or their parents to identify media use or outdoor time. Multiple linear regression models were used to investigate the potential influencing factors. A total of 342 boys and 353 girls with an average age (SD) of 12.91 (3.29) years participated. The mean AL (SD) was 23.20 (0.86)mm. The mean macular thickness (SD) was 320.53 (12.29) μm and the mean RNFL thickness (SD) was 102.88 (8.79)μm. Statistical analysis revealed a significant correlation between average macular thickness and age (p < 0.001, β=0.77) as well as AL (p < 0.001, β=-4.06). In addition, boys had thicker maculae (p < 0.001, β=5.36). The RNFL thickness showed no significant correlation with children's age (p > 0.05), but with AL (p=0.002, β=-2.15), birth weight (p=0.02, β=0.003) and a gender-specific effect of the body mass index standard deviation score for male participants (p=0.02, β=1.93). This study provides normative data and correlations between macular and RNFL thickness in healthy German children. Especially age, gender and AL must be taken into account when evaluating quantitative OCT measurements to classify them as normal.