Myopic Patients Research Articles

Pentacam and Corvis ST findings in myopic Chinese patients with different corneal diameters in Singapore.

To study the effect of corneal white-to-white diameter on Pentacam Scheimpflug cornea tomography and Corvis ST corneal visualization Scheimpflug technology parameters in myopic eyes. In this retrospective cross-sectional study, 190 eyes of 190 Chinese myopic patients (spherical equivalent range: -1.25 D to -11.00 D) assessed for refractive surgery using Pentacam and Corvis ST devices were included. Patients were divided into groups based on corneal diameter: group A <12 mm, and group B ≥12 mm. Age, gender, spherical equivalent, Pentacam variables, and Corvis ST variables were collected. Statistical analysis was performed using IBM SPSS Statistics (Version 28.0). There were 110 patients in group A and 80 patients in group B, with no statistically significant difference in age, gender, or spherical equivalence. For Pentacam data, group A had significantly higher Belin/Ambrosio Enhanced Ectasia Display (BAD-D) scores than group B (0.88 vs. 0.44) and pachymetric progression index (minimum, average, and maximum), and steeper front keratometric values, whereas group B had larger anterior chamber depth and maximum Ambrosio-relational thickness (ARTmax) (462.54 vs. 503.93). BAD-D indices, pachymetric progression indices, and front keratometric values had negative correlations with corneal diameter, whereas ARTmax and back keratometric values had positive correlations. For Corvis ST data, group A had a significantly higher corneal biomechanical index (CBI) (negatively correlated) while group B had a higher Ambrosio relational thickness to the horizontal profile (ARTh) (473.60 vs. 570.78) (positively correlated). Corneal diameter influences both Pentacam and Corvis ST parameters, with smaller corneal diameters having a higher BAD-D and a lower ARTmax and ARTh. In addition, this is the first study to report a correlation between posterior surface corneal power and corneal diameter. As refractive surgery evaluation relies on these parameters, taking corneal diameter into account would improve both sensitivity and specificity in pre-refractive surgery screening for ectasia/keratoconus.

Characteristics of the fundus and optical coherence tomography angiography metrics in myopic patients with myelinated retinal nerve fibers

AimsTo investigate the fundus characteristics and macular optical coherence tomography angiography (OCTA) metrics in patients with myelinated retinal nerve fibers (MRNF) and to identify the associations among myopic parameters, fundus metrics, and OCTA metrics.MethodsThe single-center case-control study included 15 patients with monocular MRNF and 15 patients without MRNF, matched for age, affected eyes’ spherical equivalent error (SER), and axial length (AL) between May 2021 and December 2021. Fundus features, including the entire MRNF area (Area1), the denser MRNF area (Area2), and the shortest distance from the fovea to the MRNF border (Df−m), along with ocular parameters, including SER, AL, best corrected visual acuity (BCVA), and OCTA metrics at the fovea, including choroidal (ChT) and retinal (ReT) thicknesses at the fovea, the foveal avascular zone area (FAZ), foveal avascular zone perimeter (FAZP), FAZ-circularity index (FAZ-CI), and foveal vessel density in a 300-µm wide region (FD-300), were assessed.ResultsThe SER, AL, and BCVA were significantly different, and the ChT was thinner in the affected eyes than in the contralateral eyes. Compared with matched eyes, affected eyes had reduced BCVA and thinner ReT. In the affected eyes, both Area1 and Area2 were negatively correlated with SER (r1 = -0.84, r2 = -0.65), △SER (r1 = -0.86, r2 = -0.61), ReT at the vertical superior 3 mm (VS) (r1 = -0.78, r2 = -0.67), and ChT_VS (r1 = -0.64, r2 = -0.62), and positively correlated with AL (r1 = 0.82, r2 = 0.52) and BCVA (r1 = 0.54, r2 = 0.59). Df−m was negatively correlated with BCVA (r = -0.57).ConclusionThe presence of MRNF affects BCVA and ReT at the fovea. The area of the MRNF, as well as the distance from the MRNF to the fovea, are closely associated with the affected eyes’ BCVA, SER, AL, and the degree of anisometropia.

One-Year Visual and Refractive Outcomes of SmartPulse® Technology in Transepithelial Photorefractive Keratectomy for Myopic and Astigmatic Patients.

Background/Objectives: This study aims to evaluate the efficacy, safety, and predictability of Transepithelial Photorefractive Keratectomy (TPRK) using the SmartPulse® technology excimer laser for the correction of myopia and myopic astigmatism, assessing visual and refractive outcomes over a one-year follow-up period. Methods: This retrospective cohort study analyzed data from patients who underwent TPRK at the Ophthalmology Department-"Victor Babes" University of Medicine and Pharmacy in Timisoara (Romania), between January 2019 and June 2023. The procedure was performed using the SmartPulse® Technology of the SmartSurfACE AMARIS 750S excimer laser (SCHWIND eye-tech-solutions, Kleinostheim, Germany). Preoperative assessments included visual acuity, refraction, and corneal measurements, with postoperative evaluations conducted for up to 12 months. Results: This study included 92 eyes from 46 patients (mean age 29.02 years, 63% male). At 12 months post-op, 100% achieved UDVA 20/25 or better, with an efficacy index of 1.01. Refractive accuracy was 96% within ±0.50 D of the target and astigmatism ≤ 0.50 D in 99% of eyes. The safety index was 1.01. Corneal haze occurred in 8.70% of eyes and was effectively managed with dexamethasone drops. Conclusions: TPRK with the SmartPulse® technology excimer laser demonstrated high efficacy and safety in correcting myopia and myopic astigmatism, achieving stable visual outcomes over one year. The procedure also showed excellent predictability with a low incidence of complications, supporting its use as a reliable refractive surgery option.

Cone dysfunction in ARR3-mutation-associated early-onset high myopia: an electrophysiological study

BackgroundMyopia-26, a Mendelian form of early-onset high-myopia (eoHM) caused by mutations in the X-chromosomal ARR3 gene and predominantly affecting females, curiously, may provide an alternative route of investigation to unveil retinal mechanisms underlying pathological eye growth. We conducted a case-control cross-sectional prospective electrophysiological study in genetically characterized Myopia-26 patients (ARR3 heterozygous symptomatic females) compared with high myopes harboring intact ARR3 alleles and one carrier hemizygous male.ResultsParticipants were 26 volunteers: 10 healthy control females (E-CTRL, mean age = 31.5 ± 8.8 years), one healthy control male, one carrier male of the mutant ARR3 allele and 14 female eoHM patients (mean age = 27.0 ± 13.1 years) divided in two groups: seven without (M-CTRL) and seven with (MYP-26) genetic alteration in the ARR3 gene. The clinical evaluation included complete eye screening and full-field electroretinograms (ERGs) recorded from both eyes under mydriasis. Spherical equivalent was comparable (mean=-9.55 ± 2.46 and − 10.25 ± 3.22 for M-CTRL and MYP-26, respectively) and best corrected visual acuity (BCVA) was significantly different between M-CTRL and MYP-26 (1.0 vs. 0.406 ± 0.253, respectively). E-CTRL and M-CTRL showed similar light-adapted flash and flicker ERG amplitudes; however, the prior values were reduced by ~ 35% (a- and b-waves alike), the latter by ~ 55% in the MYP-26 group (F(2, 45) > 21.821, p < 0.00001). Dark-adapted a-wave amplitudes were slightly reduced (by ~ 20%) in all myopic patients compared to E-CTRL, irrespective of the ARR3 genotype (E-CTRL vs. eoHM, p = 0.038).ConclusionsThe cone dysfunction observed in Myopia-26 patients is specifically linked to the mutation of ARR3, and is not the consequence of eoHM, i.e. elongation of the eye. It may play a role in myopic refractive error development through a yet unconfirmed pathomechanism.

Clinical characteristics of disc hemorrhages depending on their locations and glaucoma progression in myopic patients

This study aimed to investigate clinical characteristics and glaucoma progression in eyes with disc hemorrhage (DH) in the region of peripapillary atrophy (PPA) or DH in temporal region among glaucoma patients with myopia. One hundred ninety-six eyes of 196 glaucoma patients with myopia who were observed at least 4 years and had more than six visual field (VF) tests were included. Eyes with DHs located in the optic disc region at the superotemporal or inferotemporal locations were defined as typical DH. PPA area, disc ovality ratio, and disc torsion were measured. Length of γ-zone PPA, distance from disc edge to fovea, angle of scleral bending were measured using optical coherence tomography. Comparison of baseline characteristics between eyes with and without DH in PPA/DH in temporal region showed similar axial length (26.95 ± 1.60 mm; 26.82 ± 1.07 mm). γ-zone PPA was longer and angle of scleral bending was larger in eyes with DH in PPA/DH in temporal region (both p ≤ 0.001). Longer γ-zone PPA (β = 1.001; p = 0.018) and larger angle of scleral bending (β = 1.033; p = 0.008) were associated with presence of DH in PPA/DH in temporal region using logistic regression analysis. Eyes with DH in PPA/DH in temporal region had a smaller mean deviation slope of VF, a larger disc ovality ratio, a longer γ-zone PPA, and a larger PPA area when compared to those of eyes typical DH. VF progression was associated with absence of DH in PPA/DH in temporal region (p = 0.030) and larger angle of scleral bending (p = 0.019) using Cox proportional hazards model. DH in PPA/DH in temporal region was associated with stretching and deformation of sclera that may be result from myopic changes. Associated factors with VF progression was the degree of scleral deformation, not the presence of DH in PPA/DH in temporal region, showing that DH related to scleral deformation may possess clinical significance in glaucoma with myopia.

Changes in Lens Structure in Pathological Myopia, Cataract Surgery and Special Situations

Pathological myopia is a major cause of low vision and blindness worldwide. In patients with pathological myopia, there are changes such as thinning of the lens and increase in equatorial diameter. In various population and clinic-based cohort, case-control and cross-sectional studies, it has been reported that myopic patients have a higher risk of posterior subcapsular cataract, cortical and nuclear cataract. It is known that the modern technique of phacoemulsification and intraocular lens implantation is effective in highly myopic eyes and provides significant improvement in visual acuity. However, complications related to phacoemulsification such as posterior capsule rupture, retinal detachment, progression of existing maculopathy, capsular phimosis, late lens dislocation and transient intraocular pressure elevation occur more frequently in highly myopic patients. As a result, it is extremely important that cataract surgeries of these patients are performed by experienced surgeons and that attention is paid to perioperative and postoperative complications.

Ocular Motility Disorders in Pathologic Myopia

Myopia describes a refractive condition of the eye in which light rays are focused in front of the retina and is typically associated with axial elongation. The prevalence of myopia ranges from 0.8% to 75% in various population surveys. It has the highest prevalence in Asian populations. Myopia is associated with an increased risk of cataracts, glaucoma, macular degeneration, choroidal neovascularization, peripheral retinal degeneration and retinal detachment. Myopia may also be associated with abnormal ocular mobility. Strabismus associated with myopia can present in a variety of ways. In this review article, we will discuss the issues related to ocular motility disorders in pathologic myopic patients known as myopic strabismus fixus.

Axial Shortening Effects of Repeated Low-level Red-light Therapy in Children with High Myopia: A Multicenter Randomized Controlled Trial

PurposeTo evaluate the effectiveness and safety of RLRL in delaying the progression of high myopes -6.00 D or worse. DesignMulticenter, randomized, parallel-group, single-blind clinical trial. ParticipantsTwo hundred and two high myopic children aged 7 to 12 years with cycloplegia spherical equivalent refraction (SE) ≤ -6.00 D, astigmatism less than 2.50 D, anisometropia of 1.50 D or less were enrolled from March 2022 to December 2022. Follow-up was completed in December 2023. MethodsEligible participants were randomly allocated to either the intervention (RLRL + single vision spectacle [SVS]) or the control group (SVS). The RLRL treatment was administered every day for 3 minutes, twice a day, with an interval of at least 4 hours. Main Outcomes MeasuresThe primary outcome was the change in axial length (AL) at 12 months compared to baseline. Secondary outcomes included changes in SE, changes of choroidal thickness (ChT) and retinal thickness (RT) in different circle sectors. Outcomes were analyzed by means of intention-to-treat and per-protocol methods. ResultsAfter 12-month treatment, AL and SE changes were -0.11 ± 0.25 mm and 0.18 ± 0.63 D for RLRL group and 0.32 ± 0.09 mm and -0.80 ± 0.42 D for control group. Axial shortening > 0.05 mm was observed to 59% in the RLRL and 0% in the control group at 12 months. ChT and RT from a single center were analyzed. In the RLRL group, ChT were thickened in all sectors at 12 months. RT was increased in parafoveal and perifoveal circles. In the control group, all sectors of ChT and only perifoveal RT were significantly thinner at 12 months. The multivariate linear regression model revealed significant correlations between changes in ChT central foveal circle and RT perifoveal circle at 1 month and AL changes at 12 months. No fundus structure changes, afterimage exceeding 6 minutes nor best corrected visual acuity decreased reported. ConclusionsRLRL could effectively shorten the AL and inhibit the progression of myopia in high myopic patients -6.00 D or worse. AL shortening is sustained over 12 months of treatment. These observed changes appeared to be associated with increases in ChT and RT.

Peripapillary choroidal vascularity of paediatric myopic eyes with peripapillary hyperreflective ovoid mass-like structures.

To assess the peripapillary choroidal vasculature in paediatric myopic patients with and without peripapillary hyperreflective ovoid mass-like structures (PHOMS). This prospective study includes 60 eyes of 60 myopic (spherical equivalent [SE] <-1.00 dioptre [D]) patients with (n = 30) and without (n = 30) PHOMS (PHOMS [+] and PHOMS [-] groups, respectively), and 30 eyes of 30 age- and sex-matched emmetropic children (control group). Peripapillary choroidal parameters, including total choroidal (TCA), luminal (LA), and stromal areas (SA) and choroidal vascularity index (CVI) calculated from vertical and horizontal single-line enhanced depth imaging-optical coherence tomography scans centred on optic nerve head. Peripapillary retinal nerve fibre layer thicknesses were not different between the groups (p > 0.05). In the PHOMS (+) group, TCA, LA and SA were lower, and CVI was higher in all quadrants compared to the control (p < 0.05). However, only the mean TCA and LA in the inferior and nasal quadrants and the mean SA in the nasal quadrant were lower in PHOMS (+) than in PHOMS (-) (p < 0.05). In the PHOMS (-) group, higher CVI was observed in all quadrants except temporal compared to the control group. Although the mean CVI of the PHOMS (+) group was also higher than in the PHOMS (-) group, this difference was not statistically significant. This study indicates that choroidal parameters differ in paediatric myopic patients with PHOMS. Further studies with larger sample sizes are needed to understand the details of choroidal parameters in eyes with PHOMS.

Factors Predicting Slow Visual Recovery Following Myopic Photorefractive Keratectomy.

To identify factors predicting slow visual recovery following photorefractive keratectomy (PRK). This retrospective study included consecutive patients who underwent PRK between January 2005 and December 2019 at Care Vision Laser Center, Tel Aviv, Israel. Myopic patients were divided into 2 groups according to whether they experienced normal recovery of visual acuity (within 60 days) or slow visual recovery (>60 days). Visual recovery was defined as achieving an efficacy index of 0.9 or greater. Efficacy index was calculated as postoperative uncorrected visual acuity/preoperative best corrected visual acuity. A comparison of baseline and intraoperative parameters was performed. Binary logistic regression was performed to identify potential predictors of slow visual recovery. Overall, 4868 eyes were included. The mean age was 25.9 ± 7.7 years, and 53.9% were male. The slow visual recovery group (39.3%, n = 1911/4868) was older (P < 0.001) and had greater refractive astigmatism (P < 0.001) with a larger proportion of recent contact lens wearers (P = 0.002). The slow recovery group had larger optic zone treatments (P < 0.001), alcohol-assisted PRK (vs. transepithelial PRK) (P < 0.001), and greater maximum ablation depth (P < 0.001). In binary logistic regression, older age (P < 0.001), higher refractive astigmatism (P = 0.01), recent contact lens wear (P = 0.01), greater optic zone treatment (P = 0.001), and alcohol-assisted PRK (P < 0.001) remained significant predictors of slow visual recovery. Slow visual recovery was observed in ∼40% of patients following myopic PRK. Older age, greater refractive astigmatism, recent contact lens wear, greater optic zone treatment, and alcohol-assisted PRK were associated with slow visual recovery.

Analysis of third and fourth corneal high-order aberrations before and after small incision lenticule extraction (SMILE) in myopic and myopic astigmatic eyes using ray tracing aberrometry

BackgroundAim is to analyze alterations in third and fourth corneal higher-order aberrations using a ray tracing aberrometer (iTrace) induced by SMILE (small incision lenticule extraction) refractive surgery on Algerian patients; and also to investigate how corneal aberrations vary with spherical equivalent (SE), corneal central thickness (CCT), and age. Design Prospective, non-randomized case series that were carried out at the Chiali Smile Center, Algiers, Algeria.ParticipantsA total of 219 eyes from 110 myopic patients, with and without astigmatism, successfully concluded the ultimate follow-up. Participants exhibited an average age of 32.48 years, with preoperative mean corneal high-order aberrations (CHOA) measuring 0.005 ± 0.036 μm.MethodsA tracking trend analysis of high-order aberrations (HOAs) was conducted on the three groups of patients, assessing total corneal high-order aberrations after SMILE over periods of two, six, and twelve months.ResultsA substantial increase in total corneal high-order aberrations following SMILE, with a P value < 0.05. Conversely, there was a noteworthy and significant decrease in vertical trefoil for all groups (P value = 0.000). Interestingly, the corneal higher-order aberrations were more pronounced after two months compared to the six and twelve-month intervals. Spherical aberration demonstrated a significant increase with the extent of preoperative myopia and preoperative spherical equivalent both before and after SMILE surgery (P < 0.05), particularly in cases of high myopia. Moreover, there were significant reductions in preoperative and postoperative vertical coma (P = 0.047, P = 0.004, respectively) corresponding to the degree of preoperative myopia, with a more substantial decrease in vertical coma observed in cases of low myopia.ConclusionIn the post-SMILE period, a notable increase in vertical coma and spherical aberrations was observed, accompanied by a significant decrease in vertical trefoil across all eyes. These aberration changes were identified to be closely associated with the spherical equivalent.

Effect of Laser-Assisted in Situ Keratomileusis on Endothelial Cell Count

Background: LASIK is a popular refractive surgery for correcting myopia, but its impact on endothelial cell count (ECC) remains uncertain, with potential implications for corneal health.Objective: To determine the effect of LASIK on ECC in myopic patients.Methods: A cross-sectional study was conducted at Military Hospital, Rawalpindi, from January to July 2023. A total of 178 myopic patients (38.76% males, 61.24% females; mean age 25.21 ± 8.19 years) underwent LASIK. Baseline and post-procedural ECC were measured using specular microscopy at one week, one month, and three months post-LASIK. Central corneal thickness (CCT) and best corrected visual acuity (BCVA) were also assessed. Data analysis was performed using SPSS version 25, with paired t-tests for comparisons and significance set at p ≤ 0.05.Results: Mean ECC decreased from 2897.49 ± 93.52 cells/mm² at baseline to 2892.36 ± 94.21 cells/mm² at one week, 2846.65 ± 93.80 cells/mm² at one month, and 2811.10 ± 90.66 cells/mm² at three months post-LASIK (p &lt; 0.001). Mean CCT also significantly decreased at all time points (p &lt; 0.001).Conclusion: LASIK significantly reduces ECC, highlighting the need for careful postoperative monitoring of corneal health.

Effect of posterior chamber phakic refractive lens implantation on the ocular surface and tear film

To evaluate changes in dry eye-related parameters after posterior chamber phakic refractive lens (PC-PRL) implantation. This prospective study included 21 highly myopic patients (39 eyes) who underwent PC-PRL implantation at Lanzhou Huaxia Eye Hospital between January 2021 and June 2022, with a 3-month postoperative follow-up. In addition to routine preoperative examinations, dry eye assessments were conducted preoperatively and at 1 week, 1 month, and 3 months postoperatively. These assessments included the Ocular Surface Disease Index (OSDI) questionnaire score, non-invasive first tear break-up time (NIF-BUT), non-invasive average tear break-up time (NIA-BUT), tear meniscus height (TMH), meibomian gland loss (MGL) rate, and Schirmer I test (SIt). Repeated measures ANOVA was used to compare the differences in parameters across different time points, with pairwise comparisons conducted using the LSD-t test. After grouping, the Student's t-test was applied to compare normally distributed data, while the Mann–Whitney U test was used for non-normally distributed data. Categorical data were analyzed using the chi-square test. A total of 21 patients (39 eyes) were included, comprising 10 males (19 eyes) and 11 females (20 eyes), aged 19 to 49 years (33.76 ± 7.87). All patients completed the 3-month follow-up. Significant differences in OSDI scores were observed pre- and post-surgery (P = 0.008), with a peak at one week post-surgery (P < 0.001), then stabilizing at one and three months post-surgery. Postoperative NIF-BUT and NIA-BUT significantly decreased (P < 0.001 for both) but returned to preoperative levels within three months. There were no significant changes in TMH, MGL, or SIt postoperatively (P > 0.05). Significant differences in dry eye parameters were observed between the dry eye and control groups before and after surgery (P < 0.001). PC-PRL implantation impacts tear film stability on the ocular surface after surgery, leading to varying degrees of dry eye symptoms in patients. After surgery, all dry eye parameters return to their preoperative levels within three months.

SEQUENTIAL PARS PLANA VITRECTOMY AND INVERTED INTERNAL LIMITING MEMBRANE FLAP TECHNIQUE FOR RHEGMATOGENOUS RETINAL DETACHMENTS WITH PERIPHERAL BREAKS AND CONCOMITANT NONCAUSATIVE MACULAR HOLE IN NONHIGHLY MYOPIC PATIENTS.

To present the anatomical and functional results of sequential pars plana vitrectomy for treating rhegmatogenous retinal detachment with peripheral breaks and concomitant noncausative macular holes (MHs) in nonhighly myopic patients. Medical records of patients who underwent rhegmatogenous retinal detachment surgical repair between 2017 and 2023 were reviewed. Of 980 patients with rhegmatogenous retinal detachment, 10 had concurrent MH and underwent sequential pars plana vitrectomy for rhegmatogenous retinal detachment repair and air endotamponade, followed by MH repair using the inverted internal limiting membrane flap technique and C2F6 endotamponade after a minimum of 1 week. The main outcomes measured were best-corrected visual acuity change, retinal reattachment rate, MH closure rate, and closure type. The retinal reattachment rate was 90% after the primary surgery and 100% after subsequent surgery. Macular hole closure was achieved in all cases. Macular hole diameters ranged from 291 to 702 µm. Anatomical recovery showed mainly 1A closure types (90%). Functional recovery demonstrated significant best-corrected visual acuity improvement, with a mean visual acuity gain of 1.58 ± 0.41 the logarithm of the minimum angle of resolution. For this infrequent pathology, sequential surgery using the inverted internal limiting membrane flap technique and air/gas endotamponade yielded favorable anatomical and functional outcomes. This controlled and standardized approach using sequential surgeries contributes to the achievement of consistent results.

Study on the relationship between adolescent myopia and gut microbiota via 16S rRNA sequencing

Myopia has become a global public health problem, with a high incidence among adolescents. In recent years, the correlation between gut microbiota and various diseases has become a research hotspot. This paper analyzes the relationship between myopia and gut microbiota in adolescents based on 16S rRNA sequencing, opening up a new avenue for the prevention and control of myopia. 80 adolescents aged 6–15 years were included; fecal samples were collected to compare their diversity and species differences. There was no significant difference in α diversity when considering richness and evenness at the same time (P > 0.05). While the group difference in β diversity reached a significant level (R2 = 0.022, P < 0.05). The absolute quantification and relative abundance of phylum level Firmicutes and Actinobacteriota are different; among the top 30 genera, myopic group only one genus decreased in absolute quantification, while 13 genera decreased in relative quantification; so LEfSe analysis was performed, and the result showed that microbial community composition changed under Linear discriminant analysis (LDA) score, the top ten changes are shown in the figure; the Wilcoxon Rank sum test also found some significant changes in the absolute abundance of differential microbiota among different groups, at the phylum level, one bacterial phylum decreased and three bacterial phyla increased; at the genus level, 2 bacteria genera decreased and 29 bacteria genera increased. Functional pathways prediction found many myopic-related pathways were functionally enhanced in myopic patients (P < 0.05). Multivariate logistic regression analysis results showed that the area under the curve (AUC) of myopic patients predicted was close to or equal to 1. In conclusion, adolescent myopia is closely related to the gut microbiota, and the characteristic gut microbiota can distinguish myopia from healthy controls to a large extent. Therefore, it can be considered to regulate these characteristic gut microbiota to prevent and control myopia.

Macula Characteristics in Young Saudi Male Patients with Myopia: A Comparative Hospital-Based Study.

Myopia is associated with changes in the posterior segment of the eye, including the macula, which may contribute to potential blindness. Therefore, the study aims to evaluate the macula integrity in young myopic patients through optical coherence tomography (OCT). A cross-sectional study was conducted at Qassim University optometry clinics from January to June 2024, involving 30 healthy young males with myopia and 30 with emmetropia. Clinical examination and OCT imaging were used to gather data on macular volume and thickness. The results were analyzed using descriptive statistics and correlation analysis. The study included 60 myopic eyes and 60 emmetropic eyes. The participants' mean age was 22.10 ± 1.65 years (p = 0.135). A significant difference was found between myopic and emmetropic eyes in fovea, parafovea, perifovea, and total macula thickness and volume (P < 0.05). Additionally, the study showed a significant positive correlation between the magnitude of myopia and fovea thickness (r = 0.297, p = 0.011) and negative correlations with perifovea thickness (r = -0.418, p < 0.001), total macula thickness (r = -0.353, p = 0.003), and total macula volume (r = -0.352, p = 0.003). However, parafoveal thickness had no significant correlation with the severity of myopia (r= -0.107; p=0.207).Fovea thickness was higher in high myopia (255.40 ± 23.51 µm) compared to low (238.69 ± 15.98 µm) and moderate (248.15 ± 8.70 µm) myopia. Perifovea thickness, macula thickness, and macula volume were significantly lower in high myopia (p ˃ 0.05). Myopia influences macular parameters compared to emmetropia. It increases fovea thickness and decreases total macula thickness and volume as well as perifovea thickness. High myopia has more alterations in macula parameters.

Refractive Error Impact on Video Head Impulse Test Outcomes.

The objective of this study is to investigate the potential influence of refractive error on Video Head Impulse Test outcomes. Eighty-two patients were included in the study, and all patients underwent video head impulse testing. Patients were divided into four groups according to their refractive error: myopia, myopia-astigmatism, astigmatism, and emmetropia as control. Patients with myopia are younger than patients with astigmatism and controls; similarly, patients with myopia-astigmatism are younger than patients with astigmatism. The right and left lateral, anterior, and posterior gain values were statistically significantly lower in the control group compared with myopia and myopia-astigmatism patients (p < 0.05). There was a statistically significant relationship between the right and left lateral, anterior, and posterior gain values and the degree of myopia in the patients (p < 0.05). The results of the Video Head Impulse Test gain in myopia patients are higher than that in patients without refractive error. In addition, age may have an effect on gain values. It is important to consider this factor when evaluating the results of the Video Head Impulse Test in patients, and corrections should be made if necessary. Level 3 Laryngoscope, 2024.

Comparison between a new transepithelial PRK vs. conventional alcohol-assisted PRK: Corneal densitometry and aberrometry study.

To describe and compare corneal densitometry, subjective refraction, visual acuity, and corneal higher order aberrations (HOA) after corneal refractive surgery using either alcohol-assisted photorefractive keratectomy (aaPRK) or single-step transepithelial PRK (tPRK). We conducted a retrospective and observational study. We analyzed 120 right eyes from 120 healthy consecutive myopic patients who underwent aaPRK or tPRK to correct myopia of up to 6 diopters and astigmatism of up to 2 diopters. The WaveLight EX500 excimer laser (Alcon Laboratories, Inc.) was used in all cases. Visual acuity, subjective refraction, and Pentacam AXL® measurements were performed at the preoperative visit and at 6-months follow-up visit. Pentacam AXL® software was used to assess corneal optical density in various annuli for different corneal depths and anterior corneal HOA (6 mm area of analysis). Preoperative spherical equivalent values were similar between groups preoperatively (-3.07 ± 1.52 and -3.38 ± 1.46 in the aaPRK and tPRK groups, respectively). There were no statistically significant differences in visual acuity and postoperative refraction between groups. Postoperative corneal densitometry did not show statistically significant differences in any of the areas studied and both surgical procedures obtained similar results. However, analysis of HOA showed statistically significant differences between the techniques (1.42 ± 0.39 and 1.80 ± 0.62 for the aaPRK and tPRK groups, respectively; p = 0.000). Both aaPRK and single-step tPRK gave comparable visual, refractive, and corneal density outcomes. Some differences were observed in HOA but were not clinically relevant.

Visual Prognosis Following Cataract Surgery in Highly Myopic Patients with Prior History of Verisyse Phakic Intraocular Lens Implantation.

Background/Objectives: This study aimed to evaluate the visual outcomes and prognosis after cataract surgery in patients with prior history of Verisyse phakic intraocular lens (pIOL) implantation. Methods: A retrospective cohort study involving 215 Verisyse pIOL implantations and 17 explantations was conducted. The Verisyse pIOL was disenclaved and removed through a superior scleral tunnel incision. Cataract extraction with phacoemulsification was then performed through a temporal clear corneal incision. Results: An occurrence rate of 7.9% of eyes with cataract formation was found. Both uncorrected (UDVA) and corrected visual acuity (CDVA) three months after cataract surgery were significantly improved (0.24 ± 0.30 vs. 0.73 ± 0.48; p < 0.001 and 0.10 ± 0.14 vs. 0.30 ± 0.31; p = 0.004, respectively). The UDVA was 20/20 or better in 41% of eyes and 20/40 or better in 65% of eyes. The CDVA was 20/20 or better in 53% of eyes and 20/40 or better in 88% of eyes. The safety and efficacy indices were 1.96 ± 1.68 and 1.60 ± 1.36, respectively. Conclusions: Various complications including cataracts may develop in these patients. Verisyse pIOLs have a lower incidence of cataract formation and are more likely to lead to age-related cataracts rather than the anterior subcapsular cataracts commonly seen in implantable collamer lens (ICL) patients. Patients with a prior history of Verisyse pIOL can expect to have a good visual prognosis after cataract extraction.

Efficacy of small incision lenticule extraction combined with femtosecond laser-assisted in situ keratomileusis for optimized monovision correction in myopia patients with presbyopia

Objective: To evaluate the efficacy of optimized monovision correction using small incision lenticule extraction (SMILE) and femtosecond laser-assisted in situ keratomileusis (FS-LASIK) in myopic patients with presbyopia and to assess the corneal epithelial remodeling following these procedures. Methods: A prospective study was conducted. Thirty-two patients (64 eyes) with myopia and presbyopia who underwent surgical correction at Chongqing Bai Ji Eye Clinic from August 2021 to April 2023 were continuously included. There were 9 males and 23 females, with an average age of (44.25±2.96) years. The dominant eyes (32 eyes) underwent SMILE, while the non-dominant eyes (32 eyes) underwent FS-LASIK with mild myopia and partial negative spherical aberration induction. Data on visual acuity and refraction were collected preoperatively and at 1 week, 1 month, 3 months, and 6 months postoperatively. Total ocular aberrations were measured using the iProfiler Plus, and the corneal epithelial thickness in different regions was assessed using anterior segment optical coherence tomography. Safety and efficacy indices were calculated based on visual acuity, the defocus and contrast sensitivity were measured using the Binoptometer 4P binocular vision tester, and a patient satisfaction survey was performed. Results: At 1 week postoperatively, the uncorrected distance visual acuity (UDVA) of dominant eyes significantly improved compared to preoperative values. At 3 months postoperatively, the uncorrected near visual acuity (UNVA) of non-dominant eyes showed significant improvement (P<0.05), 96.9% (31 eyes) of the dominant eyes achieved UDVA of 1.0 or better, and 93.8% (30 eyes) of the non-dominant eyes achieved UNVA of 0.8 or better. The safety index for distance vision was 1.15±0.09, and the efficacy index was 1.15±0.11. At 1 week, 1 month, 3 months, and 6 months postoperatively, the proportion of dominant eyes with a spherical equivalent (SE) deviation within ±0.50 D of the target was 90.6% (29 eyes), 90.6% (29 eyes), 93.8% (30 eyes), and 96.2% (31 eyes), respectively; for non-dominant eyes, the corresponding proportions were 81.3% (26 eyes), 87.5% (28 eyes), 93.8% (30 eyes), and 96.2% (31 eyes). The postoperative spherical aberration was (0.11±0.03) μm for dominant eyes and (-0.01±0.04) μm for non-dominant eyes, showing a statistically significant difference (P<0.05). At 1 week and 1 month postoperatively, the central corneal epithelial thickness of non-dominant eyes was significantly higher than that of dominant eyes [(71.34±21.69) μm vs. (51.97±6.33) μm at 1 week, and (61.34±15.85) μm vs. (52.72±6.32) μm at 1 month; P<0.05]. Patient satisfaction was high, with 96.9% (31 patients) rating their satisfaction as "satisfactory" or higher. Conclusions: The combined use of SMILE and FS-LASIK for optimized monovision correction in myopic patients with presbyopia is both safe and effective, achieving high postoperative satisfaction. The SMILE procedure reduces the extent of corneal epithelial remodeling compared to FS-LASIK.