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International Journal of Ophthalmology 2024To evaluate the effect of low-degree astigmatism on objective visual quality through the Optical Quality Analysis System (OQAS).
AIM
To evaluate the effect of low-degree astigmatism on objective visual quality through the Optical Quality Analysis System (OQAS).
METHODS
This study enrolled 46 participants (aged 23 to 30y, 90 eyes) with normal or corrected-to-normal vision. The cylindrical lenses (0, 0.5, 0.75, 1.0, and 1.25 D) were placed at the axial direction (180°, 45°, 90°, and 135°) in front of the eyes with the best correction to form 16 types of regular low-degree astigmatism. OQAS was used to detect the objective visual quality, recorded as the objective scattering index (OSI), OQAS values at contrasts of 100%, 20%, and 9% predictive visual acuity (OV100%, OV20%, and OV9%), modulation transfer function cut-off (MTF) and Strehl ratio (SR). The mixed effect linear model was used to compare objective visual quality differences between groups and examine associations between astigmatic magnitude and objective visual quality parameters.
RESULTS
Apparent negative relationships between the magnitude of low astigmatism and objective visual quality were observed. The increase of OSI per degree of astigmatism at 180°, 45°, 90°, and 135° axis were 0.38 (95%CI: 0.35, 0.42), 0.50 (95%CI: 0.46, 0.53), 0.49 (95%CI: 0.45, 0.54) and 0.37 (95%CI: 0.34, 0.41), respectively. The decrease of MTF per degree of astigmatism at 180°, 45°, 90°, and 135° axis were -10.30 (95%CI: -11.43, -9.16), -12.73 (95%CI: -13.62, -11.86), -12.75 (95%CI: -13.79, -11.70), and -9.97 (95%CI: -10.92, -9.03), respectively. At the same astigmatism degree, OSI at 45° and 90° axis were higher than that at 0° and 135° axis, while MTF were lower.
CONCLUSION
Low astigmatism of only 0.50 D can significantly reduce the objective visual quality.
PubMed: 38895689
DOI: 10.18240/ijo.2024.06.14 -
International Journal of Ophthalmology 2024To analyze and compare the differences among ocular biometric parameters in Han and Uyghur populations undergoing cataract surgery.
AIM
To analyze and compare the differences among ocular biometric parameters in Han and Uyghur populations undergoing cataract surgery.
METHODS
In this hospital-based prospective study, 410 patients undergoing cataract surgery (226 Han patients in Tianjin and 184 Uyghur patients in Xinjiang) were enrolled. The differences in axial length (AL), anterior chamber depth (ACD), keratometry [steep K (Ks) and flat K (Kf)], and corneal astigmatism (CA) measured using IOL Master 700 were compared between Han and Uyghur patients.
RESULTS
The average age of Han patients was higher than that of Uyghur patients (70.22±8.54 63.04±9.56y, <0.001). After adjusting for age factors, Han patients had longer AL (23.51±1.05 22.86±0.92 mm, <0.001), deeper ACD (3.06±0.44 2.97±0.37 mm, =0.001), greater Kf (43.95±1.40 43.42±1.69 D, =0.001), steeper Ks (45.00±1.47 44.26±1.71 D, =0.001), and higher CA (1.04±0.68 0.79±0.65, =0.025) than Uyghur patients. Intra-ethnic male patients had longer AL, deeper ACD, and lower keratometry than female patients; however, CA between the sexes was almost similar. In the correlation analysis, we observed a positive correlation between AL and ACD in patients of both ethnicities ( =0.48, =0.44, <0.001), while AL was negatively correlated with Kf ( =-0.42, =-0.64, <0.001) and Ks ( =-0.38, =-0.66, <0.001). Additionally, Kf was positively correlated with Ks ( =0.89, =0.93, <0.001).
CONCLUSION
There are differences in ocular biometric parameters between individuals of Han ethnicity in Tianjin and those of Uyghur ethnicity in Xinjiang undergoing cataract surgery. These ethnic variances can enhance our understanding of ocular diseases related to these parameters and provide guidance for surgical procedures.
PubMed: 38895687
DOI: 10.18240/ijo.2024.06.10 -
International Journal of Ophthalmology 2024
PubMed: 38895670
DOI: 10.18240/ijo.2024.06.25 -
Journal of Clinical Medicine Jun 2024: The number of corneal transplants is rising, with the aim to treat a spectrum of diseases ranging from dystrophies to corneal opacities caused by trauma or chemical... (Review)
Review
: The number of corneal transplants is rising, with the aim to treat a spectrum of diseases ranging from dystrophies to corneal opacities caused by trauma or chemical burns. Refractive outcomes after this procedure are often impossible to predict and associated with high levels of astigmatism. However, there are many techniques that affect the reduction of astigmatism and improve the quality of life of patients. : The aim was to compare the improvement in postoperative visual acuity (logMAR) and amount of corneal astigmatism (Diopters) after corneal keratoplasty in patients who additionally underwent a surgical procedure, which affects the reduction in postoperative astigmatism, and to determine the most effective method. A thorough search was carried out across online electronic databases including PubMed, Embrase, Ovid MEDLINE, Scopus, and Web of Science, using combinations containing the following phrases: postoperative astigmatism, post-keratoplasty astigmatism, anterior lamellar keratoplasty (ALK), deep anterior lamellar keratoplasty (DALK), posterior lamellar keratoplasty, endothelial keratoplasty (EK), penetrating keratoplasty (PK), corneal transplant, keratoplasty, refractive surgery, kerato-refractive surgery, laser in situ keratomileusis (LASIK), and femtosecond LASIK. This was to determine all English-language publications that discuss refractive operations for postoperative or post-keratoplasty astigmatism. These bibliographies were searched for English-language publications published between 2010 and 2023. We proceeded to review each detected record's reference list. Study characteristics such as study design, sample size, participant information, operations performed, and clinical outcomes were all extracted. The Comprehensive Meta-Analysis software (version 3.3.070, 2014) was used to perform the analysis. The threshold of 0.05 for -values was considered statistically significant. All effect sizes are reported as standardized differences (Std diff) in means with a 95% confidence interval (CI) and visualized graphically as forest plots. Publication bias is presented as a funnel plot of standard error by Std diff in means. Four methods were used to evaluate the heterogeneity among the studies: Q-value, I, chi-square (χ), and tau-squared. We included 21 studies that randomized 1539 eyes that underwent corneal transplantation surgery either by PKP, DALK, or DSEAK techniques. The results showed the most significant improvement in the visual acuity and significant decrease in the corneal astigmatism after laser surgery procedures, like femtosecond-assisted keratotomy after DALK and PKP and LASIK after DSEAK.
PubMed: 38893017
DOI: 10.3390/jcm13113306 -
Journal of Clinical Medicine May 2024To investigate the efficacy and safety of one-year treatment with 0.03% atropine eye drops for slowing myopia progression among children aged 6-12 years. Healthy...
To investigate the efficacy and safety of one-year treatment with 0.03% atropine eye drops for slowing myopia progression among children aged 6-12 years. Healthy Caucasian children aged 6-12 years with cycloplegic spherical equivalent (SE) from -1.0 D to -5.0 D and astigmatism and anisometropia ≤1.5 D were included. Changes in mean axial length (AL) and objective SE as well as changes in intraocular pressure (IOP), central corneal thickness (CCT), anterior chamber depth (ACD) and lens thickness (LT) were assessed in the 0.03% atropine eye drops group and the control group from baseline through the 1-year follow-up. The proportion of participants showing myopia progression of <0.5 D from baseline in each group and any potential side effects in 0.03% atropine group were evaluated. The study involved 31 patients in the 0.03% atropine eye drops group and 41 in the control group. Administration of 0.03% atropine for 1 year resulted in a mean change in SE of -0.34 (0.44) D/year, significantly lower than the -0.60 (0.50) D/year observed in the control group ( = 0.024). The change in AL was 0.19 (0.17) mm in the 0.03% atropine group, compared to 0.31 (0.20) mm in the control group ( = 0.015). There were no significant differences in changes of IOP, CCT and LT between the groups (all ≥ 0.05). The 0.03% atropine group had a significantly greater increase in ACD compared to the control group ( = 0.015). In total, 64.5% of patients in the 0.03% atropine group showed progression <0.5 D/year, in contrast to 39.0% in the control group ( = 0.032). Adverse events were reported in 13 (35.0%) out of 37 patients in the treatment group, leading to discontinuation of the eye drops in six (16.0%) cases. None of the adverse events were severe. Despite a higher incidence of adverse events, 0.03% atropine eye drops effectively slowed the progression of myopia over 1-year.
PubMed: 38892929
DOI: 10.3390/jcm13113218 -
Journal of Clinical Medicine May 2024: Refractive errors, including myopia, hyperopia, and astigmatism, are the leading causes of visual impairment in school-aged children and can significantly impact their...
: Refractive errors, including myopia, hyperopia, and astigmatism, are the leading causes of visual impairment in school-aged children and can significantly impact their academic performance and quality of life. This study aimed to assess the prevalence of refractive errors among school children from economically disadvantaged areas in Northwest México, using a consistent methodology to facilitate comparison with global data. : We adopted the Refractive Error Study in Children (RESC) protocol by the World Health Organization to examine the prevalence of myopia, hyperopia, and astigmatism. The study comprised a systematic sampling of children aged 6 to 18 years from diverse schools in Northwest México. Trained optometrists conducted visual acuity testing and autorefraction, while ophthalmologists performed cycloplegic refraction to ensure accuracy. : The study found a myopia (SE ≤-1.50 D at least one eye) prevalence of 14.55% (95% CI: 13.27-15.91), with a higher incidence in females (6.92%) compared to males (6.00%) in at least one eye. Hyperopia (SE ≥ +1.00 D at least one eye) was less common, at 3.23% (95% CI: 2.61-3.95), with a slightly higher occurrence in males in at least one eye. Astigmatism (Cylinder ≥ 0.75 D at least one eye) was present in 18.63% (95% CI: 17.21-20.12) of the students in at least one eye, with no significant difference between genders. These findings are consistent with other studies in regions such as Puerto Rico and Iran, indicating widespread refractive error issues among schoolchildren. : The high prevalence of refractive errors, particularly myopia and astigmatism, highlights the critical need for regular vision screenings in schools and the implementation of public health interventions to provide corrective eyewear. Our study confirms the importance of utilizing standardized methodologies like the RESC protocol to compare refractive error prevalence across different geographical and socio-economic contexts, thereby informing global public health strategies.
PubMed: 38892805
DOI: 10.3390/jcm13113094 -
Clinical Ophthalmology (Auckland, N.Z.) 2024Corneal transplantation, when used in the correct setting, can significantly improve visual acuity and therefore quality of life. One of the barriers to good vision... (Review)
Review
Corneal transplantation, when used in the correct setting, can significantly improve visual acuity and therefore quality of life. One of the barriers to good vision following keratoplasty is residual post operative surgical astigmatism. Following a thorough literature search, we present the different options available to readers, with regards to how post-operative astigmatism can be approached and managed in order to improve vision. We present available data from the literature, which in some areas are scarce, with a view to collating all of this information in one place, allowing comparison between different modalities of treatment.
PubMed: 38887510
DOI: 10.2147/OPTH.S393975 -
Frontiers in Medicine 2024Myopia is a major global health issue, especially among children and adolescents. Understanding its traits and progression is vital for proper management and prevention....
PURPOSE
Myopia is a major global health issue, especially among children and adolescents. Understanding its traits and progression is vital for proper management and prevention. This study aimed to fill a gap in research by analyzing demographic and refractive data concerning myopia among children and adolescents in Croatia, with the goal of providing insights into myopia prevalence, progression rates, and associated risk factors within the Croatian population.
DESIGN
This retrospective study utilized a comprehensive dataset from pediatric ophthalmology clinics at the University Eye Department, University Hospital "Sveti Duh," Zagreb, Croatia. The dataset included electronic medical records spanning from January 2008 to July 2023, encompassing demographic and refractive data.
METHODS
Data analysis focused on individuals aged 4 to 18 years who were diagnosed with primary myopia and/or compound myopic astigmatism. Ophthalmic examinations, including visual acuity tests, cycloplegic refraction, and assessments for eye comorbidities, were conducted by experienced pediatric ophthalmologists. Statistical analysis, including t-tests, survival analysis, and logistic regression, was performed to assess myopia prevalence, progression rates, and associated factors. These analyses were adjusted for covariates such as age, parental myopia, and gender.
RESULTS
The study included 895 individuals, 51 premyopes, 813 low myopes, and 31 high myopes. The average age of diagnosis was 11.37 ± 3.59 years for premyopes, 11.18 ± 3.53 years for low myopes, and 11.44 ± 4.35 years for high myopes. The fastest progression occurred in 2021 and 2022, -0.5 ± 0.12 D/y for premyopes and - 0.45 ± 0.1 D/y for low myopes. Premyopic progression to low myopia was associated with age 7-9 years (HR 2.42, 1.53 to 3.21) and both parents being myopic (HR 920.27. 850.16 to 950.53). Low myopic individuals with both myopic parents displayed the fastest 11-24 months after first visit progression rates, -0.69 (-0.52 to -0.87) D/y, while the 7-9 age group demonstrated -0.36 (-0.24 to -0.45) D/y. Low myopes aged 7-9 years with baseline SE between -6 D and -4 D were more strongly associated with ≤ - 0.5 D progression (OR = 2.0, 95% CI -1.00 to 2.39).
CONCLUSION
This study highlights the importance of environmental factors, genetics, and age in addressing myopia progression among Croatian youth, urging further research for effective local intervention strategies.
PubMed: 38882670
DOI: 10.3389/fmed.2024.1405743 -
BMC Ophthalmology Jun 2024To comparatively analyze the surgically induced astigmatism (SIA) of the anterior, posterior, and total corneas of eyes undertaking implantable collamer lens (ICL)... (Comparative Study)
Comparative Study
Analysis of surgically induced astigmatism of the anterior, posterior, and total cornea after implantable collamer lens implantation: a comparative study between temporal and superior clear corneal incisions.
BACKGROUND
To comparatively analyze the surgically induced astigmatism (SIA) of the anterior, posterior, and total corneas of eyes undertaking implantable collamer lens (ICL) implantation with temporal or superior corneal incisions.
METHODS
One hundred and nine eyes of 109 patients who received ICL implantation were recruited: 40 eyes had temporal incisions and 69 eyes had superior incisions. Total corneal refractive power (TCRP); simulated keratometry of the anterior (Sim-K) and posterior (Sim-K) corneal curvature; and astigmatism of the anterior (CA), posterior (CA), and total (CA) cornea were recorded through a Pentacam preoperatively and 3 months postoperatively. The SIA of the anterior, posterior, and total cornea were also compared between the two groups.
RESULTS
There were no significant intergroup differences for TCRP, Sim-K, Sim-K, CA, CA, or CA, preoperatively. However, values of CA, CA, and CA with temporal incision were significantly higher than those parameters with superior incision postoperatively. All of the SIA of the anterior, posterior, and total cornea were significantly lower for temporal incision than those with a superior incision (p < 0.001, p = 0.006 and p = 0.001 respectively). Meanwhile, the superior incisions created against-the-rule (ATR) astigmatism, and temporal incisions always induce with-the-rule (WTR) astigmatism in total cornea.
CONCLUSIONS
A superior incision may be suitable for correcting WTR astigmatism, while a temporal incision for correcting ATR astigmatism when using a non-toric ICL. Meanwhile, temporal incision could be a better choice with little preoperative astigmatism or that preoperative astigmatism would be corrected with toric ICLs.
TRIAL REGISTRATION
Registration number: ChiCTR2100051739. Prospectively registered: 01 October 2021.
Topics: Humans; Astigmatism; Female; Male; Adult; Cornea; Lens Implantation, Intraocular; Visual Acuity; Refraction, Ocular; Young Adult; Phakic Intraocular Lenses; Myopia; Middle Aged; Corneal Topography; Retrospective Studies; Postoperative Complications; Prospective Studies
PubMed: 38867207
DOI: 10.1186/s12886-024-03501-x -
BMC Ophthalmology Jun 2024Refractive errors, amblyopia, strabismus, and low vision are more common among children with hearing impairments in comparison with their hearing peers. Neglecting...
BACKGROUND AND AIM
Refractive errors, amblyopia, strabismus, and low vision are more common among children with hearing impairments in comparison with their hearing peers. Neglecting visual disorders can pose educational and social problems for these children. The present study aimed to assess the prevalence of refractive errors, amblyopia, strabismus, and low vision among hearing-impaired and deaf students in Kermanshah.
MATERIALS AND METHODS
A total of 79 deaf and hearing impaired students within the age range of 7-20 years (mean age of 15.01 ± 2.72) underwent optometric examinations, including autorefractometry, retinoscopy, ophthalmoscopy, slit lamp, visual acuity measurement, and cover-uncover test. Those who needed further evaluation were referred to the Ophthalmology Clinic of Imam Khomeini Hospital.
RESULTS
Regarding the prevalence of refractive errors, 32 (40.5%) subjects had one or a combination of refractive errors, the most common of which was astigmatism (36.7%), followed by amblyopia (15.1%). The most common type of strabismus was latent strabismus (heterophoria) (88.6%), followed by exophoria (81%). Moreover, 3 (3.7%) cases had nystagmus. A significant difference was observed between the prevalence of amblyopia and the degree of hearing loss (P = 0.026), and no significant difference was detected in other cases.
CONCLUSION
As evidenced by the obtained results, refractive errors, amblyopia, strabismus, and low vision are more prevalent among deaf and hearing-impaired children compared to normal children because deaf and hearing-impaired children are not able to convey their vision problems and need to compensate for their poor hearing with an enhanced sense of sight, inattention to these disorders can present these children with serious educational and social problems. Therefore, eye screening examinations are of paramount importance in deaf and hearing-impaired children.
Topics: Humans; Strabismus; Child; Adolescent; Male; Female; Refractive Errors; Vision, Low; Amblyopia; Prevalence; Young Adult; Visual Acuity; Iran; Cross-Sectional Studies; Persons With Hearing Impairments; Deafness; Students
PubMed: 38867144
DOI: 10.1186/s12886-024-03515-5