Axial Length Research Articles

Associations of genetic variants for refractive error and axial length in adults with ocular endophenotypes in children: a cross-sectional and longitudinal study

AimsTo investigate the associations of genetic variants previously linked to axial length (AL) and spherical equivalent refraction (SE) in adults with refractive error and related endophenotypes in children, at baseline...

Prevalence and associations of parapapillary scleral ridges: the Beijing Eye Study

PurposeTo explore the prevalence and associated factors of parapapillary scleral ridges (PSRs).MethodsOut of the cohort of the population-based Beijing Eye Study (n=3468 participants), the study included all eyes with an...

Clinical characteristics and diagnostic test for spherophakia: A retrospective analysis

BackgroundThis study aimed to analyze ocular characteristics in patients diagnosed with spherophakia, establish effective diagnostic criteria, and aid clinicians in prompt identification and management. MethodsA retrospective case series identified spherophakia cases through medical records and literature searches. The case group included spherophakia patients, and the control group comprised individuals with similar eye conditions. Intraocular lens calculations used the SRK-T formula, and statistical analyses were performed using SPSS. Diagnostic efficacy was assessed through receiver operating characteristic (ROC) curve analysis. ResultsThe study included 12 cases (23 eyes) from medical records and 86 patients (142 eyes) from literature sources. Characteristics of spherophakia included bilateral involvement, younger age, shallow anterior chamber depth, lens dislocation, and secondary glaucoma. A diagnostic criterion based on lens power demonstrated high sensitivity (94.3 %) and specificity (91.9 %). ROC analysis yielded area under the ROC curve (AUROC) values of 0.974 for lens power, outperforming refractive error (0.119), corneal curvature (0.465) and axial length (0.496). The lens power cutoff for diagnosing spherophakia was 31.25D. ConclusionThe study offers crucial insights into spherophakia's clinical characteristics and presents a practical diagnostic criterion using lens power, enhancing early detection and management. Further research is needed to validate and refine these findings, establishing standardized diagnostic criteria for spherophakia.

Axial length acquisition success rates and agreement of two swept-source optical biometers in eyes with dense cataracts.

Swept-source optical coherence tomography-based (SS-OCT) biometers have been used in different clinical studies with the aim of assessing the accuracy of the technique, specifically in eyes with dense cataracts. Our objective is to evaluate the axial length acquisition success rates and agreement of two SS-OCT biometers when measuring axial length and biometric parameters in eyes with dense cataracts. 46 eyes (46 patients) with dense cataracts (LOCS III grade ≥ 4) were measured 3 consecutive times using the Eyestar 900 and Argos SS-OCT biometers. Keratometry (K1, flat and K2, steep), central corneal thickness (CCT), white-to-white (WTW), anterior-chamber-depth (ACD), lens-thickness (LT), and axial length were measured using both biometers. The percentage acquisition success rate and a Bland-Altman analysis to determine the agreement between the biometers were calculated. Corrected and uncorrected distance visual acuity, subjective refraction, and axial length (to assess preoperative axial length accuracy) were measured 1-month post-cataract surgery. The mean LOCS III score was 4.37 ± 0.68. The acquisition success rates for both biometers was 100%. There were statistically significant differences between the two SS-OCT biometers for all parameters evaluated (p < 0.05). The mean differences for K1, K2, CCT, WTW, ACD, LT and axial length were 0.106 D, 0.128 D, -6.347 μm, -0.054 mm, 0.095 mm, 0.110 mm, and -0.036 mm, respectively. The mean pre- and post-surgery axial length difference was -0.036 mm for the Eyestar 900 and -0.020 mm for the Argos. This difference was ≤ 0.1 mm in 97.82% of eyes with the Eyestar 900 and in 100% of eyes with the Argos. SS-OCT biometry successfully measures axial length in dense cataracts. The differences between biometers in some parameters may have a clinically significant impact but should be judged individually. The pre- and post-surgery axial length differences for each biometer can be considered clinically negligible and should not affect the IOL power calculation.

The Efficacy of Prismatic Bifocal Spectacle Lenses in Controlling Myopia Progression in Children.

Objective: Progression of myopia can lead to vision impairment and increase the risk of sight-threatening complications. Various strategies were described to control the progression of myopia, including the use of specialized spectacle. This retrospective study aimed to analyze the efficacy of prismatic bifocal spectacle lenses in controlling the progression of myopia in pediatric patients. Materials and Methods: Fifty-two eyes of 26 patients using prismatic bifocal spectacle lenses were retrospectively analyzed. Both eyes of each patient with a cycloplegic objective refraction measurement of ≥-2.00 D were included. Demographic data of the patients such as age and gender were investigated. The increase in objective spherical equivalent and axial length over the one year of single-vision spectacle use was compared with the increase observed one year after the prescription of bifocal prismatic spectacle. Results: The mean age of the patients was 11.65 ± 2.70 years. Sixteen patients were male, and 10 patients were female. The increase in mean spherical equivalent in eyes using single vision spectacles over one year was 1.25 ± 0.76 D, compared to 0.24 ± 0.14 D with prismatic bifocal spectacles, which was statistically significant). Similarly, the increase in mean axial length was 0.66 ± 0.31 mm with single vision spectacles and 0.014 ± 0.015 mm with bifocal spectacle, also statistically significant Multiple linear regression analysis revealed that baseline higher myopia and baseline shorter axial length were significantly associated with the treatment effect. Conclusion: The findings suggest that bifocal prismatic lenses have the potential to be an effective intervention for managing myopia in children, particularly those with high rates of progression. However, further research with larger sample sizes and longer follow-up periods is needed to fully understand the long-term impacts of this treatment approach.

Efficacy of Combining Highly Aspherical Lenslets Spectacles With 0.01% Atropine Eye Drops in Myopia Control

To explore the difference in myopia control efficacy between spectacle lenses with highly aspherical lenslets (HAL) combined with 0.01% atropine eye drops and spectacle lenses with HAL alone or single vision spectacle lenses (SVL) in children and adolescents. A retrospective cohort study was conducted with a total of 105 myopic children aged 6-15 years. According to the specific myopia correction and control methods of each subject, they were evenly divided into the HAL+0.01% atropine (HAL+AT) group, the HAL group, and the SVL group, with 35 subjects in each group. Relevant data, such as cycloplegic refraction and axial length (AL) at baseline and 12 months after wearing spectacles, were retrieved. One-way analysis of variance, or the Kruskal-Wallis test, was used to analyze the changes in AL and spherical equivalent refraction (SER) after wearing spectacles for 12 months in comparison to those at baseline in the three groups. There was no statistically significant difference in the baseline parameters and duration of wearing spectacles among the three groups (P>0.05). After wearing spectacles for 12 months, the changes in SER were －0.13 (－0.25, 0.00) D, －0.25 (－0.63, －0.25) D, and －0.63 (－1.00, －0.25) D in the HAL+AT group, HAL group, and SVL group, respectively; AL elongation in the three groups was (0.09±0.11) mm, (0.19±0.16) mm, and (0.34±0.16) mm, respectively. The HAL+AT group exhibited slower SER changes (P HAL+AT vs. HAL=0.001, P HAL+AT vs. SVL=0.002) and AL elongation (P HAL+AT vs. HAL=0.009, P HAL+AT vs. SVL=0.001) than those of the HAL and the SVL groups. Compared with those of the SVL group, myopia progression was reduced by 79.4% and AL elongation was slowed down by 73.5% in the HAL+AT group, while in the HAL group, myopia progression and AL elongation were reduced by 60.3% and 44.1%, respectively. According to stratified analysis based on age and myopia progression rate, among younger children aged 6 to 8 years and older children aged 9 to 15 years, the HAL+AT group had a significantly lower proportion of subjects experiencing fast AL elongation (AL>0.36 mm/year) and a significantly higher proportion of subjects experiencing slow AL elongation (AL≤0.18 mm/year) compared to the SVL group (P<0.017). The combination intervention of spectacle lenses with HAL and 0.01% atropine eye drops is effective in controlling myopia progression in children and adolescents, with better myopia control effect achieved using this combination intervention in myopic children of all ages.

Precise prediction of size of a foldable capsular vitreous body via computerized three-dimensional ocular reconstruction in severe retinal detachment

BackgroundThis study aimed to precisely predict the size and silicone oil injection of a foldable capsular vitreous body (FCVB) via computerized three-dimensional (3D) ocular reconstruction in the treatment of severe retinal detachment in China.MethodsThe 3D software Unigraphics NX was applied to determine the volume of the inner cavity with 16–30 mm axial length, assigning the anterior and posterior chambers, the FCVB sizes, and the silicone oil injection volume, and modeling the data between the axial length and the FCVB size. In clinical practice, IOL Master was applied to accurately measure the axial length of the contralateral healthy eye to anchor the anterior-posterior and horizontal diameters of the operated eye in horizontal position CT, and compared with the model to recommend the FCVB size and silicone oil amount, and the clinical effect was validated in cases across five hospitals in China.ResultsFor the axial length of 16–30 mm, the volume of the inner cavity is 1.2 ml-8.4 ml. FCVB size and silicone oil volume were recommended based on this volume of the inner cavity. Of 253 cases, we noted 11 cases implanted with AV-10P and 1.05 ± 0.21 ml of silicone oil, 41 with AV-12P and 1.58 ± 0.18 ml of silicone oil, 163 with AV-13.5P and 2.48 ± 0.29 ml of silicone oil, 31 with AV-15P and 3.57 ± 0.39 ml of silicone oil, and 7 with AV-17P and 5.71 ± 0.81 ml of silicone oil. There was no significant difference in postoperative visual acuity scores compared with preoperative (P = 0.097), postoperative IOP(10.29 ± 0.57mmHg)was slightly higher than preoperative IOP (9.76 ± 0.48 mmHg), but there was still no statistically significant difference between the two comparisons (P = 0.405).ConclusionThree-dimensional reconstruction prediction is a good solution for eyeballs with obvious individualized changes in severe retinal detachment, and this method helps doctors standardize FCVB size selection and the silicone oil amount for patients.

Measurement of the Tilt Angle of the Optic Disc Using Spectral-Domain Optical Coherence Tomography and Related Factors in Myopia.

This study presents a novel, three-dimensional method for measuring the tilt angle of the tilted optic disc (TOD) using spectral-domain optical coherence tomography (SD-OCT) and investigates the correlation between ocular-related parameters and TOD. We included the right eyes of 243 healthy young individuals, categorized by axial length. We measured the ovality index (OI) and dihedral angle (DA) using SD-OCT infrared ray fundus photographs and high-resolution cross-sectional images of the optic disc, respectively. The relationships between OI, DA, and ocular-related parameters were analyzed. Eyes in the longer axial length group exhibited a lower OI and a higher DA, along with thinner nasal and inferonasal circumpapillary retinal nerve fiber layer (cpRNFL) and thicker temporal and superotemporal cpRNFL. There was a significant relationship between DA and cpRNFL thickness. The new method utilizing DA to measure the tilt angle of TOD demonstrated high repeatability. We propose a novel, three-dimensional, and quantitative method for evaluating the tilt degree of TOD. A higher degree of myopia indicated a greater tilt angle of the TOD, and a greater TOD suggested additional changes in cpRNFL thickness. These findings should be considered when interpreting increased susceptibility and early assessment of glaucoma in myopia. DA could serve as a superior indicator for describing TOD morphology during eyeball elongation and evaluating its impact on related parameters of the optic disc and peripapillary structures in the myopic population.

Comparison of measurements and calculated lens power using three biometers: a Scheimpflug tomographer with partial coherence interferometry and two swept source optical coherence tomographers

PurposeTo compare the biometric measurements obtained from the Pentacam AXL Wave, IOLMaster 700, and ANTERION and calculate the recommended intraocular lens power using the Barrett Formulae.MethodsThis was a retrospective cross-sectional study of patients who underwent biometry using the Pentacam AXL Wave, IOLMaster 700, and ANTERION. Flat keratometry (K1), steep keratometry (K2), anterior chamber depth (ACD), and axial length (AL) from each device were measured and compared. These parameters were used to calculate the recommended IOL powers using the Barrett formula.ResultsThe study included 252 eyes of 153 patients. The IOLMaster had the highest acquisition rate among the two biometers. The Pentacam obtained the shortest mean AL, the IOLMaster measured the highest mean keratometry values, and the ANTERION measured the highest mean ACD. In terms of pairwise comparisons, keratometry and axial length were not significantly different between the Pentacam-IOLMaster and ANTERION-IOLMaster groups, while the rest of the pairwise comparisons were statistically significant. In nontoric and toric eyes, 35–45% of patients recommended the same sphere of IOL power. In another 30–40%, the Pentacam and ANTERION recommended an IOL power one step greater than that of the IOLMaster-derived data. 50% of the study population recommended the same toric-cylinder IOL power.ConclusionsThe Pentacam AXL Wave, IOLMaster 700, and ANTERION can reliably provide data for IOL power calculations; however, these data are not interchangeable. In nontoric and toric eyes, 35–45% of cases recommended the same sphere IOL power, and in another 30–40%, the Pentacam and ANTERION recommended one-step higher IOL power than the IOLMaster-derived data. In targeting emmetropia, selecting the first plus IOL power is advisable when using the Pentacam and ANTERION to approximate the IOL power calculations recommended by the IOLMaster 700.

Comprehensive assessment of corneal microstructural changes following V4c implantable collamer lens surgery using in vivo confocal microscopy

BackgroundImplantable Collamer Lense (ICL) presents a viable alternative to conventional refractive surgeries, but their impact on corneal microstructure remains unclear. By employing in vivo confocal microscopy (IVCM), we examined changes in stromal and endothelial cells following the insertion of V4c ICLs, with the goal of enhancing post-surgical care and outcomes.MethodsIn this longitudinal investigation, we conducted detailed preoperative assessments on 103 eyes from 53 participants. Follow-up evaluations were carried out after surgery at set intervals: one day, one week, one month, three months, six months, and twelve months. We used IVCM to analyze changes in stromal and endothelial cells. To assess differences between pre- and post-surgery variables and to investigate correlations with age, axial length (AL), and spherical equivalent refraction (SER), we applied a repeated measures mixed-effects model, with statistical significance set at P < 0.05.ResultsNo vision-threatening complications were reported post-surgery. Significant reductions in stromal cell density (SCD) were observed postoperatively, with anterior and mid- SCD reaching their lowest values at 3 months and posterior SCD at 1 month, remaining below baseline at 12 months. endothelial cell density (ECD) and percentage of hexagonal cells (PHC) decreased initially, recovering by 12 months. Conversely, endothelial cellular area (ECA) and coefficient of variation of cell size (CoV) increased postoperatively, with the most significant change at 1 week. Endothelial deposits were detected in 49 of 101 eyes on postoperative day 1, half of them were absorbed within 3 months post-surgery. Changes in posterior SCD were negatively related to AL, while AL, SER, lens thickness showed associated with endothelium changes.ConclusionOur findings elucidate the corneal microstructural changes following V4c ICL implantation, particularly the significant early reductions in stromal and endothelial cell densities. We recommend careful management of viscoelastics during surgery to minimize endothelial deposits that may harm the endothelium. Enhanced early postoperative monitoring and these surgical adjustments can lead to improved surgical and post-surgical care, ultimately supporting better patient recovery.

Optimizing axial length measurement success in advanced cataract patients through pupil dilation.

To evaluate the impact of pharmacologic pupil dilation on axial length (AL) measurement in patients with dense cataracts and previous failed AL measurements carried out without pupil dilation. Retrospective case series. All participants underwent swept-source optical coherence tomography (SS-OCT) biometry. Patients with unsuccessful AL measurements due to dense cataract underwent an additional SS-OCT biometric evaluation after pupil dilation, and the SS-OCT AL measurement was compared to the immersion ultrasound. The study included 3668 eyes of 3668 patients who underwent SS-OCT between October 2021 and March 2023. Of them, 102 eyes (2.8%) had failed AL measurements because of dense cataract. Eighty-seven of those 102 eyes underwent a repeat SS-OCT biometric exam following pharmacologic pupil dilation, after which AL measurements were successfully achieved in 27 (31.0%) of the 87 eyes. These measurements were found to be consistent with immersion ultrasound, supporting the validity of SS-OCT biometer measurements post dilation. Pharmacologic pupil dilation improved the rate of successful SS-OCT biometrically measured AL in patients with failed AL measurement due to dense cataract.

Numerical Study of High-g Combustion Characteristics in a Channel with Backward-Facing Steps

High gravity (high-g) combustion can significantly increase flame propagation speed, thereby potentially shortening the axial length of aero-engines and increasing their thrust-to-weight ratio. In this study, we utilized the large eddy simulation model to investigate the combustion characteristics and flame morphology evolution of premixed propane–air flames in a channel with a backward-facing step. The study reveals that both the increase in centrifugal force and flow velocity can enhance pressure fluctuations during combustion and increase the turbulence intensity. The presence of centrifugal force promotes the occurrence of Rayleigh–Taylor instability (RTI) between hot and cold fluids. The combined effects of RTI and Kelvin–Helmholtz instability (KHI) enhance the disturbance between hot and cold fluids, shorten the fuel combustion time, and intensify the dissipation of large-scale vortices. The increase in fluid flow velocity can raise the flame front’s hydrodynamic stretch rate, thereby enhancing the turbulence level during combustion to a certain extent and increasing the fuel consumption rate. When a strong centrifugal force is applied, the global flame propagation speed can be more than doubled. Within a certain range, the increase in high-g field strength can enhance the intensity of RTI and accelerate the transition of RTI to the nonlinear stage.

Retinal nerve fiber layer thickness and radial peripapillary capillaries density in myopic adults with optical coherence tomography angiography

PurposeTo evaluate retinal nerve fiber layer thickness (RNFLT) and radial peripapillary capillaries (RPC) density in adults with different degrees of myopia using optical coherence tomography angiography (OCTA) and explore their relationship with ocular factors, such as axial length (AL) and disc area.MethodsA total of 188 subjects were included in this cross-sectional study. The eyes were divided into four groups according to AL. OCTA was used for the assessment of RNFLT, RPC density, and other optic disc measurements, such as disc area. One-way analysis of variance was performed to compare differences between four groups, and P value < 0.01 was considered significant.ResultsThe RNFLT was significantly thinner in high myopia (HM) group at inferior nasal (IN) quadrant (P = 0.004) than low myopia (LM) group, but thicker at temporal inferior (TI) quadrant (P = 0.006). The RPC density of nasal superior (NS) quadrant, nasal inferior (NI) quadrant, and inferior nasal (IN) quadrant significantly decreased as AL increasing. By simple linear regression analysis, the inside disc RPC (iRPC) density tended to be correlated significantly with AL (0.3997%/mm, P < 0.0001). Peripapillary RPC (pRPC) density was in significant correlation with AL (-0.2791%/mm, P = 0.0045), and peripapillary RNFLT (pRNFLT) was in significant correlation with disc area (0.2774%/mm2, P = 0.0001).ConclusionRNFLT and RPC density were closely associated with AL and disc area. They might be new indexes in assessing and detecting myopia development via OCTA.

Effectiveness of Defocus Incorporated Multiple Segments in Slowing Myopia Progression in Pediatric Patients as a Function of Age: Three-Year Follow-Up.

Background: The purpose of this study is to evaluate the effectiveness of Defocus Incorporated Multiple Segments (DIMSs) in slowing myopia progression in pediatric patients as a function of age. Methods: This was a non-randomized experimenter-masked retrospective controlled observational study of European individuals aged 6-16 years with progressive myopia but no ocular pathology. We retrospectively reviewed the charts of the participants allocated to receive DIMS spectacles (Hoya® MiyoSmart®) or single-vision spectacle lenses (control group). Cycloplegic spherical equivalent (SE) and axial length (AL) were measured at baseline and at 12-, 24-, and 36-month follow-ups. The results were stratified by age into four groups: patients wearing DIMS spectacles older or younger than 10 years of age (group A, 20 patients mean age 13.6 ± 2.2, and group C, 20 patients mean age 9.0 ± 1.2) and age-matched control groups (group B, 18 patients mean age 13.2 ± 2.5, and group D, 22 patients mean age 8.5 ± 0.9). Results: At 36 months, SE and AL increase were significantly reduced in groups A and C, respectively, compared to groups B and D (p < 0.05). Linear regression analysis showed a significant correlation (p < 0.05) between patient age and myopia progression for SE in groups A and C, but only in group A for AL. Groups B and D did not show any significant correlation (p > 0.05). Conclusions: DIMS spectacles seem to slow myopia progression in pediatric patients; however, their effectiveness shows the greatest results in children older than 10 years of age. Moreover, our findings suggest that AL may be the more reliable parameter for evaluating myopia progression.

Covering corneal stromal lenticule for macular hole in pathological myopia.

To evaluate the clinical effect of a new surgery technique (covering corneal stromal lenticule, CSL) for macular hole (MH) in pathological myopia. This was a prospective non-randomized series case study. Fourteen eyes of 14 patients whose axial length were more than 29 mm and suffered from MH and macular hole retinal detachment (MHRD) were included in this study. All cases were treated with 25-gauge pars plana vitrectomy (PPV) with internal limiting membrane (ILM) peeling, covering CSL and C3F8 gas tamponade. These cases were followed for 6mo, and the best-corrected visual acuity (BCVA), healing status of MH, the reattached rate of retinal detachment (RD), and reoperation rate were analyzed. All cases were successfully performed the surgery and the postoperative follow-up was completed. After surgery, MHs were healed in all 14 eyes (100%, 14/14) after assessed by optical coherence tomography. The reattachment of retina was achieved in all 6 eyes (100%, 6/6) with MHRD. BCVA was improved in 12 eyes (85.71%, 12/14), and had no significant change in 2 eyes (14.29%, 2/14). The overall mean BCVA was improved from 1.80±0.77 to 0.82±0.46 logMAR (F=10.46, P<0.01). No serious complications occurred in all cases. The new surgery technique (covering CSL) has high reattached rate of RD and high healing rate of MH in pathological myopia in the preliminary study. And it can effectively improve the visual function of patients. This new technique offers meaningful new ideas for treating refractory MH in pathological myopia.

Peripheral Superficial Retina Vascular Density and Area of Radial Peripapillary Capillaries Changes in Myopic Individuals: A Wide-Field OCT Angiography Study.

Using swept-source optical coherence tomography (SS-OCT) to explore the effect of high myopia on superficial retina vascular density (SVD) of the peripheral region and the area of radial peripapillary capillaries (RPCs). In this cross-sectional study, a total of 91 volunteers (34 male subjects and 57 female subjects) were recruited and 34 individuals in the high myopic group (group A) and 57 individuals in the low myopic group (group B). Using the wide-field OCT-angiography (OCTA; 24 × 20 mm, 120 degrees angular field) compared the peripheral SVD and the area of RPC between the two groups and investigated its correlation with ocular axial length and diopter. Peripheral SVD of group B around the supratemporal (SVD1), supranasal (SVD2), infratemporal (SVD3), and infranasal (SVD4) directions were significantly higher than those of group A (all P < 0.05). The RPC area of group B around the supranasal (RPC2) and infranasal (RPC4) were significantly larger than that of group A (all P < 0.01). Ocular axial length and diopter were significantly correlated with SVD2 and SVD4 (all P < 0.05), and they also have a significant correlation with the supratemporal (RPC1), RPC2, and RPC4 (all P < 0.05). Peripheral SVD was decreased and the RPC area was mainly reduced on the nasal side in the high myopic group. Peripheral SVD and area of RPC are significantly correlated with ocular axial length and diopter. The wide-field OCTA can be used for new detection of myopia's impact on the retinal peripheral SVD and area of peripapillary RPC, offering new insights into the progression of myopia.

2024 UK and Ireland modified Delphi consensus on myopia management in children and young people.

This work aimed to establish the largest UK and Ireland consensus on myopia management in children and young people (CYP). A modified Delphi consensus was conducted with a panel of 34 optometrists and ophthalmologists with expertise in myopia management. Two rounds of voting took place and 131 statements were agreed, including that interventions should be discussed with parents/carers of all CYP who develop myopia before the age of 13 years, a recommendation for interventions to be publicly funded for those at risk of fast progression and high myopia, that intervention selection should take into account the CYP's hobbies and lifestyle and that additional training for eye care professionals should be available from non-commercial sources. Topics for which published evidence is limited or lacking were areas of weaker or no consensus. Modern myopia management contact and spectacles are suitable first-line treatments. The role and provision of low-concentration atropine needs to be reviewed once marketing authorisations and funding decisions are in place. There is some evidence that a combination of low-concentration atropine with an optical intervention can have an additive effect; further research is needed. Once an intervention is started, best practice is to monitor non-cycloplegic axial length 6 monthly. Research is needed to identify those at risk of progression, the long-term effectiveness of individual and combined interventions, and when to discontinue treatment when myopia has stabilised. As further evidence continues to emerge, this consensus work will be repeated to ensure it remains relevant.

Risk factors for transient ciliochoroidal detachment after goniotomy with the Kahook Dual Blade

To investigate ciliochoroidal detachment (CCD) frequency and risk factors after performing goniotomy with the Kahook Dual Blade (KDB). The presence of CCD was examined using anterior-segment optical coherence tomography at postoperative day (POD) 1, month 1, and month 2 in 91 eyes of patients who underwent goniotomy with KDB. Intraocular pressure (IOP) was also measured at POD 1, POD 7, month 1 and month 2. A generalized linear mixed model analysis was used to compare the age, gender, axial length, central corneal thickness, surgical procedure (combined or single), operators (K.H. or H.O.), glaucoma type and preoperative IOP between the groups. Factors were selected from the variants when there was a probability value of less than 0.05. CCD was detected in 18 eyes (19.7%) at POD 1. For postoperative IOP, no significant differences were observed between the CCD and non-CCD groups. However, the IOP on POD 1 in the CCD that was associated with the anterior chamber group (7.7 ± 3.0 mmHg) was significantly lower than that in the non-CCD group (15.3 ± 0.9 mmHg) (P = 0.02). Mixed-effects model analysis demonstrated that the surgical procedure (combined) and operator (H.O.) were significantly associated with the higher incidence of CCD. Approximately one-fifth of all eyes exhibited CCD after goniotomy with KDB. Combining cataract surgery and goniotomy with KDB and the intraoperative procedure during the goniotomy with KDB were all found to be risk factors for developing CCD.

Effect of virtual reality-based visual training for myopia control in children: a randomized controlled trial

BackgroundTo assess the efficacy and safety of virtual reality-based visual training (VRVT) in myopia control among children.MethodsThe randomized, parallel-group, single-blind clinical trial conducted at the Department of Ophthalmology of Shanghai Tenth People’s Hospital enrolled 65 low-myopic children (aged 8 to 13 years) with cycloplegic spherical equivalent (SE) between − 0.50 and − 3.00 diopters (D), astigmatism less than − 1.00 D, anisometropia less than 1.50D, and best corrected visual acuity (BCVA) more than 0.0 logarithm (LogMAR) of the minimum angle of resolution. The participants were enrolled in December 2020, and the follow-up of this study concluded on August 2021. Children were assigned randomly to the intervention group (VRVT plus single-vision spectacle [SVS]) and the control group (only SVS without receiving VRVT). The intervention group was administered for 20 min per day with VRVT under parental supervision at home. The primary outcome was changes in axial length (AL) at 3 months. Macular choroidal thickness (mCT) was regarded as a key secondary outcome.ResultsAmong 65 participants (mean age: 10.8 years, 52.3% male), 60 children (92.3%) who completed the 3-month intervention and 6-month follow-up were included in the analysis (30 in the intervention group and 30 in the control group). The changes of AL were 0.063 ± 0.060 mm (95% confidence interval [CI], 0.074 to 0.119 mm) in the intervention group and 0.129 ± 0.060 mm (95% CI, 0.107 to 0.152 mm) and in the control group at 3 months (t = − 2.135, P = 0.037), and the mean difference between the two groups was 0.066 mm. The change of mCT were 22.633 ± 36.171 μm (95% CI, 9.127 to 36.140 μm) in the intervention group and − 3.000 ± 31.056 μm (95% CI, − 14.597 to 8.597 μm) in the control group at 3 months (t = 2.945, P = 0.005). VR vertigo was the most common adverse event which was occurred in two children (2/30, 6.67%) in the intervention group.ConclusionsVRVT is a promising method for myopia control in children with good user acceptability. Among children aged 8 to 13 years with low-myopia, nightly use of VRVT resulted in slowing myopia progression.Trial registrationThis protocol was registered with ClinicalTrials.gov (NCT06250920), retrospectively registered on 01 February 2024.

Comparison of retinal nerve fiber thickness in emmetropes, myopes and hyperopes using optical coherence tomography

Aim of this study was to analyze retinal nerve fiber layer thickness by using spectral domen Optical Coherence Tomography (OCT) in different refractive status (emmetrops, myopes and hypermetrops).A cross-sectional study involved 150 patients aged 18-40, with and without refractive errors. Three groups (Emmetropic, Myopic, Hypermetropic) were tested using spectral domain OCT after pupil dilation, comparing RNFL thickness.In this study, 150 participants were categorized into three groups: emmetropia, myopia, and hypermetropia. The age group most represented was 21-25 years, comprising 35.3% of the sample. Of the total, 80 were male (53.3%), and 70 were female. Among males, 22 patients were emmetropia, myopia in 31 and hypermetropia in 27. The mean axial length for emmetropia was 23.54 ± 0.48 SD, myopia was 24.53 ± 0.48 and hypermetropia was 22.36 ± 1.11. Hypermetropia was further categorized into low-grade 22.49 ± 1.06 SD, moderate 22.26 ± 1.12 SD and high-grade 22.45 ± 1.00 based on axial length.Myopic individuals exhibited significant RNFL thinning, particularly in the inferior and superior quadrants, resembling early glaucoma-related changes. This has implications for glaucoma suspect evaluations.