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BACKGROUND: Plusoptix photoscreeners are capable of measuring refractive errors of children from 1 meter distance, without cyloplegia. We aimed to compare refractive data obtained from the newest version of Plusoptix (model 12) with cycloplegic autorefraction. METHODS: We examined 111 consecutive children aged 3-7 years first by Plusoptix A12C under manifest condition and subsequently for cycloplegic refraction by Topcon KR-1 tabletop autorefractometer. Sphere, spherical equivalent, cylinder and axis of astigmatism measured by the two methods were analyzed to determine correlation, agreement and differences. RESULTS: Binocular examination of 111 children aged 4.86±1.27 years revealed good agreement between refractive data obtained by Plusoptix and cycloautorefraction, according to Bland-Altman plots. Significant (p < 0.001) and strong correlation was found between all refractive measurements (Pearsons r value of 0.707 for sphere, 0.756 for pherical equivalent, and 0.863 for cylinder). Plusoptix mean sphere, spherical equivalent and cylinder were 1.22, 0.56, and -1.32 D, respectively. Corresponding values for cycloautorefraction were 1.63, 1.00, and -1.26 D. The difference between axis of cylinder measured by the two methods was < 10° in 144 eyes (64.9%). CONCLUSIONS: Considering the significant agreement and correlation between Plusoptix photoscreener and cycloplegic autorefraction, the need for cycloplegic drops in refractive examination of children may be obviated. The mean difference between cylinder measurements are considerably trivial (0.06 D), but sphere is approximately 0.4 D underestimated by Plusoptix compared to cycloautorefraction, on average.

Background: Aim 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. Participants: A 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. Methods: A 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. Results: A 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. Conclusion: In 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. [ABSTRACT FROM AUTHOR]

Introduction: The aim of this study was to evaluate alterations in corneal astigmatism, axial anterior corneal curvature, anterior chamber depth, and central corneal thickness (CCT) two months after the unilateral recession of lateral rectus muscle in children. Methods: This prospective study included 37 children with intermittent exotropia who would undergo unilateral lateral rectus muscle recession. All measurements were performed using Pentacam®. Comparisons were made between the operated and fellow unoperated eyes, pre- and post-operatively. The assessment was made for changes in the radius of axial curvature on major meridians at 3 and 3.5 mm from the optical corneal center in the mid-peripheral zone. Astigmatism changes of the anterior and posterior corneal surface were calculated using vector analysis software (astigMATIC®). The interaction between age or CCT and postoperative changes in anterior and posterior surface corneal astigmatism were examined with ANOVA model. Results: In the intervention group, changes in anterior and posterior corneal surface astigmatism were statistically significant, with a mean increase of 0.56Dx90 and 0.08Dx87, respectively. In the mid-peripheral corneal zone, an increase was observed in the radius of anterior corneal axial curvature, more evident temporal 3 and 3.5 mm from the corneal center on the horizontal meridian, with corresponding decrease superiorly and inferiorly at 3 and 3.5 mm from the corneal center on the vertical meridian. Discussion: The changes in total astigmatism of the operated eyes are mainly attributed to the anterior corneal surface. These changes are associated with flattening in the 180 meridian of the cornea, leading to a shift to “with-the-rule” astigmatism. [ABSTRACT FROM AUTHOR]

Purpose Methods Results Conclusions To estimate the astigmatic power of the crystalline lens and the whole eye without phakometry using a set of linear equations and to provide estimates for the astigmatic powers of the crystalline lens surfaces.Linear optics expresses astigmatic powers in the form of matrices and uses paraxial optics and a 4 × 4 ray transfer matrix to generalise Bennett's method comprehensively to include astigmatic elements. Once this is established, the method is expanded to estimate the contributions of the front and back lens surfaces. The method is illustrated using two examples. The first example is of an astigmatic model eye and compares the calculated results to the original powers. In the second example, the method is applied to the biometry of a real eye with large lenticular astigmatism.When the calculated powers for the astigmatic model eye were compared to the actual powers, the difference in the power of the eye was 0.030.130.04TD$$ {\left(0.03\kern0.5em 0.13\kern0.5em 0.04\right)}^{\mathrm{T}}\ \mathrm{D} $$ (where T represents the matrix transpose) and for the crystalline lens, the difference was 0.080.290.08TD$$ {\left(0.08\kern0.5em 0.29\kern0.5em 0.08\right)}^{\mathrm{T}}\ \mathrm{D} $$ (power vector format). A second example applies the method to a real eye, obtaining lenticular astigmatism of −5.84 × 175.The method provides an easy‐to‐code way of estimating the astigmatic powers of the crystalline lens and the eye. [ABSTRACT FROM AUTHOR]

Background: To explore intraocular lens (IOL) preferences of United Kingdom-based (UK) refractive surgeons in cataract and refractive lens exchange (RLE) surgery. Methods: An online survey on IOL preferences (and reasons for their choice) in cataract and RLE surgery was distributed. It also enquired about implementing mini-monovision with extended depth of field (EDoF) IOLs, about utilising IOL mix-and-match (different IOL types in each eye), and at what level of corneal astigmatism they prefer toric lenses. Results: Following an 81.6% response rate, thirty responses were analysed; median years of refractive surgery experience was 12.5. The most popular IOL choices for cataract surgery were EDoF lenses (30%), monofocals (20%), and trifocals (20%). The most cited reason for each was better overall visual outcomes (88.9%), fewer unwanted symptoms (66.7%) and best spectacle independence (66.7%), respectively. For RLE, EDoF remained most popular (36.7%), followed by trifocals (30%), and multifocals (16.7%) with the same reasons for choice cited above. Mini-monovision with EDoF lenses was well-regarded (83% recommend for most/select patients), unlike utilising IOL mix-and-match (60% did not recommend). 40% prefer toric IOLs for astigmatism of 1 dioptre (D) or higher, whilst 30% opt for them at < 1D. Conclusions: Experienced UK refractive surgeons prefer newer IOLs with enhanced optics; ≥50% of respondents favoured either EDoF or trifocals for a 'typical' cataract or RLE patient. Notably, respondents have a low corneal astigmatism threshold for toric lenses. Mini-monovision with EDoF IOLs was well-regarded, whilst mix-and-match of different IOL types was less recommended. [ABSTRACT FROM AUTHOR]

PurposeMethodsResultsConclusionInterventions such as eye exams and glasses are used to correct visual problems that may lead to amblyopia, an irreversible decrease in visual acuity. Children with limited access to these interventions are more likely to have unaddressed visual problems that can lead to amblyopia or negatively impact school performance. This study compared vision screening results of children in schools with Title 1 or Non-Title 1 designation to investigate the link between poverty and vision.Data from KidsFIRST vision screenings conducted with the SPOTTM photoscreener performed in Rapid City Area elementary schools were compared across multiple parameters. Students were referred for eye examinations based on identifying the following problems: anisometropia, anisocoria, astigmatism, myopia, hyperopia, gaze misalignment, or a combination.Overall, eye exam referral rates have increased since 2012 (11.9% in 2012, 19.7% in 2023), with a disproportionate increase in referrals from Title 1 schools (25.2% in 2023) vs. Non-Title 1 schools (11.9% in 2023) (p < 0.001). This is largely due to a significantly higher prevalence of astigmatism referrals in Title 1 students (20.9%) compared to Non-Title 1 students (7.5%). Although a higher percentage of Title 1 students are reported to have eye correction (24.4% vs 16.6%), only a slightly higher percentage of Title 1 students wore eye correction during screening (11.5% vs 10.5%).Students at Title 1 schools may have a higher rate of amblyopia risk factors. Additional eye care-based interventions should be taken to reduce the risk of amblyopia in this population. [ABSTRACT FROM AUTHOR]

Purpose: To compare surgical results between ab-externo microshunt surgery and trabeculectomy, focusing on postoperative corneal astigmatism. Study design: Retrospective study. Methods: Subjects were patients with glaucoma who underwent either standalone ab-externo microshunt surgery or trabeculectomy. Data on ophthalmic examinations obtained preoperatively and 1, 3, and 5 months postoperatively were analyzed. To assess corneal astigmatism, two separate data sets measured by anterior segment optical coherence tomography and autorefractometer were evaluated. Multivariate linear mixed model analyses were conducted to identify factors associated with the astigmatism changes. Results: Sixty eyes were examined: 13 eyes underwent microshunt surgery, and 47 eyes underwent trabeculectomy. The total corneal astigmatism measurements by anterior segment optical coherence tomography (AS-OCT) were: − 1.15 ± 0.85 D and − 1.17 ± 0.81 D for the microshunt and trabeculectomy groups, respectively, preoperatively. At five months postoperatively they were − 0.92 ± 0.47 D and − 1.61 ± 0.83 D, respectively (P = 0.807 for the microshunt group and P = 0.005 for the trabeculectomy group: Wilcoxon signed-rank test). AS-OCT also indicated similar results for posterior corneal astigmatism. Autorefractometry also found the total corneal astigmatism was significantly changed only in the trabeculectomy group. The linear mixed model analysis revealed that trabeculectomy (P = 0.001), older age (P = 0.004), and longer postoperative period (P = 0.015) were correlated with greater astigmatism changes. The intraocular pressures significantly decreased following both surgical treatments. Conclusions: Standalone ab-externo microshunt surgery has less effect on corneal astigmatism during a 5 month period than trabeculectomy. Both surgical procedures significantly reduced intraocular pressure. [ABSTRACT FROM AUTHOR]

Background: Pterygium is atriangular fibroelastic degeneration of the conjunctiva and subconjunctival tissue. Methods: quasi experimental study, comprising 52 patients aged from 35 to 60 during perid from April 2021 to April 2022 who underwent pterygium excision and autologus conjunctival graft. A total of 52 participants were enrolled and followed before and after 1 and 3 months after surgery by pentacam Scheimpflug camera . Results: there were significant changs in keratometric astigmatism at 1 month and 3 months compared with preoperative mean keratometric astigmatism, and there were statistically significant reduction in mean refractive astigmatism at 1 month and3 months postoperatively compared with preoperative mean refractive astigmatism. Also, a significant increase of spherical power of the cornea, there were statistically significant increase in average K1 at 1 month 3 months postoperatively compared with preoperative average K, There were statistically significant increase in average K 2 after 1 month,3 months, postoperatively compared with preoperative average K2, The mean BCVA was 0.31(0.13 SD) equivalent Decimal value preoperatively and improved significantly at 1 month postoperatively 0.48 (0.13 SD) equivalent Decimal value, P <0.001) and 3 months postoperatively 0.60( 0.13 SD), P <0.001) when compared with preoperative values. Conclusions: pterygium excision was associated with significant improvement in astigmatism. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to evaluate the intraoperative complications and visual outcomes of manual deep anterior lamellar keratoplasty (mDALK) in patients who underwent previous radial keratotomy (RK) for myopia. Methods: The notes of patients who underwent mDALK after RK at three different hospitals—San Giovanni Addolorata Hospital (Rome, Italy), Mount Saint Joseph Hospital (Vancouver, Canada), and Tor Vergata University Hospital (Rome, Italy)—were retrospectively reviewed. We analyzed the manual dissection success rate and conversion to penetrating keratoplasty (PK), the residual recipient stromal thickness, the postoperative corrected distance visual acuity (CDVA), postoperative refraction, and topographic astigmatism. Results: Thirteen eyes of eleven patients were included in the analysis (male 7/11, 63.6%). Preoperatively, mean topographic astigmatism was 5.4 ± 3.5 D (range 1.6–14.8 D), and mean CDVA was 0.47 ± 0.2 logMAR (range 0.3–1.0 logMAR) [Snellen equivalent 20/50]. Manual dissection was performed in all cases. None of the examined eyes were converted to PK. An improvement in both topographic astigmatism (2.8 ± 0.9 D, p = 0.0135) and CDVA (0.23 ± 0.2 LogMAR, p = 0.0122) was recorded at 12-month follow-up. Conclusions: mDALK is a safe and effective surgical technique when applied to eyes previously treated with RK, with an observed improvement in CDVA and topographic astigmatism. [ABSTRACT FROM AUTHOR]