Photopic Pupil Research Articles

Biometric factors associated with the postoperative visual performance of a multifocal intraocular lens

PurposeTo identify the biometric factors associated with postoperative visual performance after uneventful phacoemulsification with multifocal intraocular lens (MIOL) implantation. MethodsIn this retrospective cohort study, 72 eyes of 72 patients implanted with the HumanOptics Diff-aAY MIOL were included. Preoperative examination data including the white-to-white distance (WTW), anterior chamber depth (ACD), axial length and corneal astigmatism were gathered through the electronic medical records. One month postoperatively, the pupil parameters, corneal aberrations, corneal astigmatism, IOL tilts and IOL decentrations were measured using an OPD-Scan III aberrometer. Postoperative visual performance parameters were recorded as the visual acuity, depth of focus, modulation transfer function (MTF) and point spread function (PSF) values, area under log contrast sensitivity function (AULCSF), retinal straylight and visual function questionnaire scores. Univariate and multivariate linear regression analyses were then performed to evaluate the associations between the potential biometric factors and postoperative visual outcomes. ResultsYounger age predicted greater MTF and PSF values, better AULCSF and better retinal straylight (P < 0.05). A lower corneal trefoil predicted better MTF and PSF values (P < 0.05). Smaller IOL decentration predicted better distance-corrected near visual acuity, greater AULCSF and better retinal straylight (P < 0.05). A less negative spherical equivalent (SE) predicted better MTF values (P = 0.017), while a more negative SE predicted better Visual Function Index-14 (VF-14) questionnaire scores and satisfaction scores (P < 0.05). A higher IOL power predicted better best corrected distance visual acuity (P = 0.005). Lower preoperative corneal astigmatism predicted greater MTF values (P = 0.020). Lower postoperative corneal astigmatism, smaller corneal high-order aberrations (HOAs), smaller photopic pupil size, larger WTW and deeper ACD predicted a better AULCSF (P < 0.05). ConclusionsIOL decentration, IOL power, age, preoperative and postoperative corneal astigmatism, SE, photopic pupil size, corneal trefoil, WTW, ACD and corneal HOAs were significantly associated with postoperative visual performance. These findings might aid in patient selection prior to MIOL implantation.

Impact of Various Concentrations of Low-Dose Atropine on Pupillary Diameter and Accommodative Amplitude in Children with Myopia.

Purpose: To assess over 2 weeks, the effect of 3 different low concentrations of atropine on pupillary diameter and accommodative amplitude in children with myopia. Methods: Fifty-eight children with myopia [spherical equivalent (SE) of -0.50 diopters (D) or worse, astigmatism of less than or equal to 2.00 D] were randomly allocated to 3 groups receiving 0.01%, 0.02%, or 0.03% atropine eye drops, once nightly for 2 weeks. The primary outcome was the change from baseline in pupillary diameter and accommodative amplitude with each of the concentrations. Results: Fifty-seven participants (114 eyes), aged between 6 and 12 years, completed the 2-week trial (mean age 9.3 ± 1.7 years and mean SE -3.53 ± 1.79 D). After 2 weeks of use, all the 3 concentrations were found to have a statistically significant effect on both the pupillary diameter and accommodative amplitude. Accommodative amplitude reduced by an average of 5.23 D, 9.28 D, and 9.32 D, and photopic pupil size increased by an average of 0.95 ± 1.05 mm, 1.65 ± 0.93 mm, and 2.16 ± 0.88 mm with 0.01%, 0.02%, and 0.03%, respectively. Of the eyes, a total of 5.3% and 5.9% of the eyes on 0.02% and 0.03% atropine had a mean residual accommodative amplitude of <5 D. The percentage of eyes having a pupillary dilation >3 mm were 4.8%, 10.5%, and 23.5% for 0.01%, 0.02%, and 0.03% atropine, respectively. Conclusions: Low-dose atropine had an effect on pupillary diameter and accommodative amplitude. With the highest concentration assessed, that is, 0.03% nearly 1 of 4 eyes had pupillary dilation of >3 mm. Clinical Trial Registration number: NCT03699423.

Intraocular pressure-related side-effects after endothelial keratoplasty.

To investigate circumpapillary retinal nerve fibre layer (RNFL) thickness, pupillary function and diameter after phacoemulsification and lens implantation alone or combined with endothelial keratoplasty (EK). This study was a secondary analysis of data from a randomized, single-masked trial, that included 72 patients with Fuchs' endothelial dystrophy and cataract, equally allocated (1:1) to ultrathin Descemet's stripping automated endothelial keratoplasty or Descemet's membrane endothelial keratoplasty. The cataract extraction (CE) group included 40 patients undergoing cataract surgery only. All patients were treated with phacoemulsification and lens implantation. RNFL thickness was significantly lower in the CE group than after EK for the global (p < 0.01), nasal (p = 0.04), and temporal sectors (p = 0.01) 12 months after surgery. RNFL thickness was comparable between patients treated with rebubbling and others (p ≥ 0.16 for all comparisons) after 12 months. The CE group and patients treated with EK demonstrated a comparable scotopic (p = 0.34) and photopic pupil diameter (p = 0.95) as well as a comparable maximum (p = 0.83) and average pupillary constriction velocity (p = 0.95) after 12 months. In contrast, patients treated with rebubbling had a significantly smaller scotopic pupil diameter (p = 0.04). In this study, no evidence was found indicating a negative impact on the RNFL thickness after EK when compared to CE 12 months after surgery. Iris function and pupil diameter were comparable between the CE group and patients treated with EK after 12 months.

Mesopic pupil indices as potential risk factors for glare disability after intraocular implantable collamer lens implantation: prospective study.

To explore the influence of preoperative factors, including varying pupil sizes and refractive attributes, on postoperative glare disability in patients undergoing implantable collamer lens (ICL) implantation. Second Affiliated Hospital, Nanchang University, Nanchang, Jiangxi, China. Prospective observational study. The preoperative ocular characteristics and 6-month postoperative glare status in eligible patients who underwent EVO-Visian ICL V4c (VICMO) implantation were analyzed. The glare disability criteria encompassed a glare symptom score >6 and glare sensitivity exceeding 1:2.7. Logistic regression analysis was used to explore the relationship between the preoperative ocular parameters and post-ICL glare. The study included 95 patients (mean age, 26.04 ± 6.29 years), comprising 30 men (58 eyes) and 65 women (129 eyes). Multivariate analysis revealed a significant correlation between postoperative glare disability and increased spherical power in preoperative mesopic pupils (β = -0.124, P = .039), as well as elevated cylinder power in preoperative mesopic (β = -0.412, P = .009) and photopic pupils (β = -0.430, P = .007). Moreover, a larger preoperative mesopic pupil diameter (β = 0.561, P = .005) demonstrated a significant correlation with glare disability. Preoperative mesopic pupil dimensions and associated refractive parameters, such as sphere and cylinder, were correlated with glare disability, including the cylinder aspect in photopic pupils, which can assist clinicians in optimizing preoperative selection for ICL implantation, aiding in the anticipation of potential glare disability risks.

Evaluation of early period changes in intraocular pressure, ocular biometry and anterior segment after upper eyelid blepharoplasty.

To investigate the acute effects of upper eyelid blepharoplasty on intraocular pressure (IOP) and ocular biometric parameters. This prospective cross sectional study examined the eyes of 49 patients with dermatochalasis. Following a detailed ophthalmological examination, corneal topography was used to evaluate the eyes mesopic and photopic pupil diameter, anterior chamber depth, and corneal astigmatism on the day of surgery and on days first and seventh postoperatively. Ocular biometry was used to assess axial length and intraocular lens power. Goldmann applanation tonometry was used to measure intraocular pressure. Forty-nine eyes (26 males and 23 females) of 49 patients aged between 44 and 76years (mean 61 ± 7.9) were included in our study. The mean anterior chamber depth (ACD) was 2.90 ± 0.37mm preoperatively, 3.00 ± 0.29mm at postoperative day first, and 3.04 ± 0.29mm at postoperative day seventh, and the increase in anterior chamber depth was statistically significant (p < 0.001). The mean astigmatism values were measured as preoperative 0.73 ± 0.69 D, postoperative first day 0.93 ± 0.81 D, and postoperative seventh day 1.26 ± 0.90 D. The increase in astigmatism values was statistically significant (p < 0.001).The mean pupil diameter measurements in the mesopic environment were 4.20 ± 0.61mm preoperatively, 4.40 ± 0.59mm on the first postoperative day, and 4.39 ± 0.57mm on the seventh postoperative day, and there was a statistically significant difference between the three measurements (p = 0.03). The mean IOP measurements of the patients were 15.91 ± 3.51mmHg preoperatively, 16.81 ± 3.36mmHg on the first postoperative day, and 16.97 ± 3.13mmHg on the seventh postoperative day. The increase between these three measurements was statistically significant (p = 0.013). This study includes important insights into the potential acute phase impact of blepharoplasty surgery on ocular findings. Patients undergoing upper eyelid surgery should be informed about the possible change in ocular biometric parameters, intraocular pressure, and pupil diameter.

Long-Term Visual Quality and Pupil Changes after Small-Incision Lenticule Extraction for Eyes without Preoperative Cylinder Refraction.

To investigate the long-term changes in visual quality and pupil size after small incision lenticule extraction (SMILE) for eyes without preoperative cylinder refraction. Thirty-three myopic eyes (33 patients) without preoperative cylinder refraction were corrected using SMILE. Refractive outcomes, corneal curvature, aberrations, contrast sensitivity (CS), and pupil diameter were evaluated preoperatively, and 30 months postoperatively. The 30-month postoperative uncorrected and corrected distance visual acuity (UDVA and CDVA, LogMAR) were -0.10 ± 0.09 and -0.14 ± 0.06, respectively, whereas the preoperative CDVA (LogMAR) was -0.07 ± 0.05. Cylinder refraction of -0.11 ± 0.21 D (ranging from -0.50 to 0.00) was observed at 30 months postoperatively, increasing from the preoperative cylinder refraction of 0.00 ± 0.00 D (P=0.004). Moreover, the centroid coordinates x, y of corneal anterior astigmatic vectors were -0.19 ± 0.22, 0.81 ± 0.33 at 30 months postoperatively, and 0.02 ± 0.28, 0.76 ± 0.51 preoperatively (Px < 0.001 and Py=0.810, respectively). Furthermore, a 15° axis change in the mean anterior corneal astigmatic vector was observed at 30 months postoperatively from the preoperative state, as measured by Pentacam. At 30 months postoperatively, the photopic Log CS reduced significantly with glare at three and six cycles/degrees (P < 0.001 and P=0.015, respectively), a decreased photopic pupil diameter (3.27 ± 0.55 mm vs. 3.10 ± 0.66 mm, P=0.030), and an increased Coma (Z31) and Trefoil (Z3-3) at 4 mm diameter area analysis. However, a significant linear regression relationship was only observed between changes in photopic pupil diameter and changes in photopic Log CS with glare at 12 cycles/degree (P=0.038 and β = 0.282). Slight cylinder regression was observed with thicker corneal lenticular extraction after SMILE correction of nonastigmatic eyes 30 months postoperatively. This regression was mainly because of the axis changes in anterior corneal astigmatism power. Therefore, a cylinder nomogram modification of 0.25 to 0.50 D is considerable for correcting nonastigmatic myopic eyes with a predicted spherical lenticular thickness over 100 µm.

Pupillary Diameter Change and Dynamics in Different Refractive Error Groups after Implantation of a Collamer Lens with a Central Hole Without Viscoelastic Agent

Background: To investigate the pupillary diameter and dynamics in different refractive error groups after non-viscoelastic agent-assisted implantation of a collamer lens with a central hole, so as to evaluate the effect on the pupil of this type of surgery. Methods: Consecutive patients with a range of refractive errors who underwent non-viscoelastic agent-assisted implantation of a collamer lens with a central hole (ICL V4c) were analyzed. OPD-Scan III (NIDEK Japan)was used to measure the pupillary diameter preoperatively and 1 month postoperatively. Pupillary dynamics were assessed by calculating the scotopic pupillary diameter minus the photopic pupillary diameter. All variables were measured under photopic and scotopic conditions. Results: In 53 patients (medium-low myopia group 44 eyes, 23 patients, age 33.3±1.2 years and high myopia group 60 eyes, 30 patients, age 31.7±1.5 years), the postoperative photopic pupil was significantly smaller than preoperatively in both groups, and the postoperative pupillary size was significantly larger in the high myopia group under both the photopic and scotopic conditions. Besides, the high myopia group had a significantly larger photopic-scotopic change postoperatively and greater change in the pupillary dynamics. Conclusion: Implantation of a collamer lens with a central hole without viscoelastic agent assistance affected the pupillary diameter and dynamics at 1 month postoperatively in the medium-low and high myopia groups. The group with medium and low diopters had stronger changes in pupil diameter after surgery, while the group with high diopters was more likely to be affected by changes in visual quality.

The influence of pupil diameter upon and subjective quality of vision following implantable collamer lens (ICL V4c) implantation: An observational study.

This study aimed to assess the change in pupil size and its influence on subjective quality of vision (QoV) in subjects with implanted collamer lenses (ICLs). This retrospective study assessed 53 participants (53 eyes) implanted with ICL (V4c) and categorized them into incremental groups according to pupil diameter. Preoperative and postoperative photopic and mesopic pupil diameter, uncorrected distance visual acuity (UDVA), and QoV questionnaire scores were assessed and compared. Postoperatively, at 3 months, UDVA was -0.10 ± 0.06 logarithm of the minimum angle of resolution (LogMAR), and mean QoV for day and night was 9.34 ± 0.76 and 8.58 ± 1.29, respectively. The mean mesopic and photopic pupil diameters were 6.59 ± 0.79 mm and 4.61 ± 0.74 mm, respectively. Photopic pupil diameter negatively correlated with "QoV day" (Rs = -0.413, P = .001), positively correlated with "haloes" (Rs = 0.568*, P < .001) and "blurred vision" (Rs = 0.243, P = .04) respectively. Mesopic pupil diameter negatively correlated with "QoV night" (Rs = -0.426, P = .001), positively correlated with "haloes" (Rs = 0.624*, P < .001), "starburst" (Rs = 0.233, P = .046) and "difficulty focusing" (Rs = 0.27, P = .025), respectively. Participants had excellent VA at 3-month follow-up. Photopic and mesonic pupil diameter negatively correlated with QoV day and QoV night scores, respectively. Pupil diameter was found to have a more significant effect on visual symptoms at night, and lower QoV due to larger pupil size was more noticeable at night. Further investigation is needed to explore the importance of pupil diameter and its impact on the QoV in ICL implanted patients.

Assessment of Pupil Size and Angle Kappa in Refractive Surgery: A Population-Based Epidemiological Study in Predominantly American Caucasians.

Purpose This retrospective study aims to establish normative values for pupil size, angle kappa, higher-order aberration, and astigmatism type in a largely Caucasian population in Utah, United States, utilizing the NIDEK OPD-Scan III system (Gamagori, Japan). Methods This study included 716 patients (1432 eyes) grouped based on spherical equivalence and age. Measurements were conducted under mesopic and photopic conditions. Statistical analysis involved Pearson's correlation and linear regression using the generalized estimating equation.NIDEK OPD-Scan III measured mesopic and photopic pupil size and angle kappa. The subjects were then grouped based on their spherical equivalence in diopters (D) and age in decades. The spherical equivalence groups were defined: >-6 D, -5.99to -3 D, -2.99to -0.25 D, -0.24to 0.24 D, and >0.25 D (range 0.25-5.75 D). The higher-order aberration groups were based on the reason for the visit: laser-assisted in situ keratomileusis, photorefractive keratectomy, and small incision lenticule extraction as one group; cataract evaluation; and keratoconus. Astigmatism measurements were grouped into with-the-rule (WRT), against-the-rule (ATR), and oblique astigmatism, with further subgrouping into a young cohort (20-40 years) and an old cohort (>65 years). Results Among 716 participants, 49.2% were men; the mean age was 42.1±15.5(range 7-88 years). The average spherical equivalence for myopia eyes was -3.28±2.34 D, and 1.51±1.46 D for hyperopia eyes. The mean mesopic pupil size was 5.68 ± 1.09 mm; the photopic pupil size was 4.65±1.09 mm. Pearson's correlation coefficient for mesopic pupil size versus age was -0.551, and -0.42 for photopic pupil (p < 0.001); sphere vs mesopic pupil size was -0.200, and -0.173 for photopic pupil(p < 0.001). The regression analysis for mesopic pupil size versus age revealed a 0.39 mm decrease in average pupil size per decade increase in age, and 0.25 mm decrease per decade for photopic pupil. The regression analysis for mesopic pupil size versus sphere revealed a 0.22 mm decrease in average pupil size per 3D increase in sphere, and a 0.16 mm decrease 3 D increase in sphere for the photopic pupil. The mean mesopic angle kappa was 0.33± 0.15 mm; photopic angle kappa was 0.31±0.15 mm. Pearson's correlation coefficient for mesopic angle kappa vs spherical equivalence was 0.32, and 0.296 for photopic angle kappa (p <0.001 for both). Regression analysis for mesopic angle kappa vs spherical equivalence demonstrated a 0.051 mm increase in angle kappa per 3 D increase in spherical equivalence, and a 0.048 mm increase for photopic angle kappa (p < 0.001 for both). Among the higher-order aberration groups, the keratoconus group exhibited the highest levels. In terms of astigmatism type, WRT astigmatism was the most common in the young cohort, while ATR astigmatism was most prevalent in the older cohort. Conclusions The results of this study reveal significant associations between pupil size and increasing age, as well as between pupil size and increasingly positive refractive errors. These findings hold particular clinical relevance to older patients and individuals with hyperopia, as they undergo photoablative corneal refractive surgery or multifocal intraocular lens implantation. Understanding the established normative values for pupil size, angle kappa, higher-order aberration, and astigmatism type can aid clinicians in making more informed decisions and improving patient outcomes.

Quality of Vision and Ocular Higher Order Aberrations after SMILE for Myopia and Myopic Astigmatism

Background Previous studies have shown considerable amounts of higher order aberrations following SMILE. In our study we aim at accurately quantifying the higher order aberrations following SMILE in myopia and myopic astigmatism. Objective To detect the effect of SMILE on quality of vision and the incidence of higher order aberrations following SMILE. Patients and Methods This is a prospective study that included 30 eyes of 18 patients presented in the outpatient clinic seeking advice for myopic refractive surgical correction. The study was conducted in accordance with the ethical standards stated by the ethical committee of Ain shams university hospitals with informed consents obtained from all participants. Results On studying the post-operative corneal third order aberrations we detected increase in post-operative vertical and horizontal coma, and spherical aberrations with non-significant change in vertical and horizontal trefoil. According to our study results, SMILE is an effective refractive surgery that improves visual acuity. That causes decrease in quality of vision through modulation transfer ratio and increase in ocular higher order aberrations. Conclusion SMILE (small incision lenticule extraction) is an efficient modality for refractive surgical correction of myopia and myopic astigmatism, with significant post-operative improvement in unaided visual acuity detected post-operative increase in the ocular HOAs. Total coma, trefoil and sphere increase significantly in mesopic more than photopic pupil. The degree of myopia didn’t affect the ocular higher order aberrations except for modulation transfer ratio.

Efficacy and safety of atropine at different concentrations in prevention of myopia progression in Asian children: a systematic review and Meta-analysis of randomized clinical trials.

To assess the efficacy versus the adverse effects of various concentrations of atropine in the prevention of myopia in Asian children. Databases (PubMed, EMBASE, the Cochrane Library and Web of science) were comprehensively searched from inception to April 2022. Types of studies included were randomized clinical trials (RCTs). The published languages were limited to English. Two researchers assessed the quality of included studies independently using Cochrane risk of bias tool based on the Cochrane Handbook for Systematic Reviews of Interventions. Funnel plots and Egger's test were used for detection of publication bias. Meta-analyses were conducted using STATA (version 15.0; StataCorp). A total of 15 RCTs involving 2268 patients were included in the study. In the atropine group, spherical equivalent progressed at a significantly lower rate [weighted mean difference (WMD)=0.39, 95% confidence interval (CI): 0.23, 0.54] than in the control group. A WMD of 0.15 mm was associated with less axial elongation (95%CI -0.19, -0.10). Different doses showed statistically significant differences (P<0.05) and an improved effect could result from a higher concentration. Changes in photopic pupil size and mesopic pupil size in atropine group is 0.70 mm (95%CI: 0.33, 1.06) and 0.38 mm (95%CI: 0.22, 0.54) more than the control group. In the present Meta-analysis, no changes in accommodative amplitude (AA) were associated with atropine administration. Atropine administration increased the risk of adverse effects by 1.37 times. Concentrations of less than 1% atropine are able to effectively retard diopter and axis growth of myopia in Asian children in a dose-dependent manner. Meanwhile, it caused pupil enlargement, but induced no change in the AA within this range. Further study is required to determine the dosage needed to achieve maximum efficacy and minimal side effects.

Retinal image quality in myopic children undergoing orthokeratology alone or combined with 0.01% atropine

BackgroundThe retinal image quality derived from lower-order (LOA) and higher-order aberrations (HOA) for fixed 3-mm and photopic pupil diameters, in children undergoing combined 0.01% atropine and orthokeratology (AOK) versus those receiving orthokeratology alone (OK) over two years was evaluated.MethodsThe visual Strehl ratio based on the optical transfer function (VSOTF), derived from 2nd- to 4th-order terms (LOA and HOA combined), 2nd-order terms (LOA only), and 3rd- to 4th-order terms (HOA only) for fixed 3-mm and natural photopic pupil diameters, was compared between the two treatment groups. The individual Zernike coefficients for a fixed 3-mm pupil size of 2nd- to 4th-orders, root mean square (RMS) of LOA ({Z}_{2}^{0}, {Z}_{2}^{-2}, and {Z}_{2}^{2} combined), HOA (3rd to 4th orders inclusive), and Coma ({Z}_{3}^{-1}{mathrm{and }Z}_{3}^{1} combined) were also compared between the two groups.ResultsRight eye data of 33 AOK and 35 OK participants were analysed. Under photopic conditions, significantly lower VSOTF based on HOA only was observed in the AOK group compared with that in the OK group at all post-treatment visits (all P < 0.05); however, interactions between HOA and LOA resulted in comparable overall retinal image quality (i.e., VSOTF based on LOA and HOA combined) between the two groups at all visits (all P > 0.05). For a fixed 3-mm pupil size, the VSOTF based on HOA only, LOA only, or HOA and LOA combined, were not different between the two groups (all P > 0.05). AOK participants had slower axial elongation (mean ± SD, 0.17 ± 0.19 mm vs. 0.35 ± 0.20 mm, P < 0.001), a larger photopic pupil size (4.05 ± 0.61 mm vs. 3.43 ± 0.41 mm, P < 0.001) than OK participants, over two years.ConclusionsHOA profile related to an enlarged pupil size may provide visual signal influencing eye growth in the AOK group.

Repeatability and Agreement between Scansys and Pentacam in Ocular Biological Parameters.

To assess the repeatability and agreement between Scheimpflug-based corneal topography, Scansys and Pentacam, in measuring ocular parameters in myopic eyes. A Grade-A tertiary hospital in Beijing, China. Cross-sectional study. The following measurements were performed in 204 patients undergoing pre-operative examinations for refractive surgery from the corneal curvature, astigmatism, corneal thickness, corneal volume, corneal asphericity, anterior chamber depth and volume, and pupil diameters. Repeatability was determined using intraclass correlation coefficient (ICC) with 95% confidence interval (95% CI), Cronbach's Alpha, coefficient of variation (CV), within-subject standard deviation (Sw), test-retest repeatability (TRT), and one-way analysis of variance (one-way ANOVA). The inter-device agreement was determined using paired t-test and Bland-Altman plots. Scansys showed good repeatability in the anterior and posterior corneal flattest meridian (Kf), steepest meridian (Ks), and mean (Km), axis of anterior corneal Ks, anterior corneal astigmatism, pupil central corneal thickness, central corneal thickness, corneal apex thickness, thinnest corneal thickness, corneal volume, photopic pupil diameter, anterior chamber depth and volume. In the agreement study, Bland-Altman plots showed that 95% LoA of corneal curvature, pupil central corneal thickness, corneal apex thickness, thinnest corneal thickness, and corneal volume generated by Scansys and Pentacam were narrow. There were no statistically significant differences in the anterior corneal Kf and Km. Scansys showed good repeatability in measuring corneal curvature of anterior and posterior surfaces, anterior corneal astigmatism, corneal thickness, corneal volume, photopic pupil diameter, anterior chamber volume and depth. Scansys and Pentacam can only be used interchangeably in measuring anterior corneal curvature.

A comparative study on slow down progression of myopia using atropine 0.01% in children

The aim of the study was to determine the efficacy of lower concentration of Atropine 0.01% in promoting unaided visual acuity and slowing down the progression of myopia in children over 6 months. It was a hospital-based comparative study in the outpatient department of Ophthalmology, AL, LT, ACD, PPD, SPD, PGP were taken by Lenstar and Lensometer.The Comparative study was performed on 60 children from 9 to 15 years age group with initial myopic spherical equivalence from 0.5 to 6.00 D. The children were screened for visual acuity for distance and near using Snellen’s chart. Cycloplegic Refraction was done to know the presence of Refractive Errors. This study was approved by IRB Ethical Committee. (SCAHS/IRB/2022/JULY/420).The inclusion criteria include Ammetropic children with no binocular vision anomalies and no history of ocular disease. The primary outcome was the rate of myopic progression after 6 months. The participants were instructed to use Atropine 0.01% eye drops during night times for 6 months and the rate of myopic progression and the spherical equivalence, axial length, lens thickness, anterior chamber depth, photopic and scotopic pupil diameter were re-assessed to compare the progression of myopia in the children. Sixty children enrolled for six months study in which the mean progression of myopia was found to be within 0.27D and axial elongation shows 0.23 mm changes respectively, whereas there were no significant changes in the anterior chamber depth, lens thickness, photopic and scotopic pupil diameter before and after assessment in children. Spherical power, Axial Length, Anterior Chamber Depth, Lens Thickness, Photopic Pupil Diameter and Scotopic Pupil Diameter all showed significant progression from pre to post stages, with the average post reading deviating by 0.25 from the normal limits.

Influence of isofocal intraocular lenses on objective refraction based on autorefraction and aberrometry.

To evaluate and compare the objective refractions obtained by autorefraction and aberrometry under different lighting conditions with an isofocal intraocular lens (Isopure, BVI medical, Liége, Belgium) compared to a monofocal control lens (Micropure, BVI medical, Liége, Belgium) with the same platform and material. Prospective, comparative and randomized study on patients undergoing cataract surgery and bilateral isofocal or monofocal IOL implantation. A total of 44 subjects were randomly assigned to either the isofocal group (n = 22) or the Micropure (n = 22). Manifest refraction (MR) was always performed under the same lighting conditions for all the patients. For objective refraction the autorefractor KR8800 and the aberrometer OPD-Scan III (Nidek Inc., Tokyo, Japan.) were used. For each eye included in the study, six result sets were collected: MR, AR (autorefraction measured with the autorefractor), WF-P and WF-M (Zernike-coefficients-based objective refraction, photopic and mesopic pupil size), OPD-C and OPD-M (autorefraction measured with the aberrometer in photopic and mesopic conditions). The mean sphere for MR was 0.03 ± 0.32D for the Isopure group and 0.24 ± 0.22D for the monofocal group (p = 0.013). For the Isopure group, Friedman analysis showed statistically significant differences for sphere measured with WF-P (p = 0.035), WF-M (p = 0.018) and OPD-M (p = 0.000), and SE measured with OPD-M (p = 0.004). In the Micropure lens group, the Friedman analysis showed differences for all values studied (p < 0.05). Correlation coefficients showed that AR is the objective method with the strongest correlation values for all components of refraction for both groups. The modification of the surfaces of the isofocal lens does not have a negative impact on the refraction obtained by AR compared to a standard monofocal intraocular lens.

Agreement between Two Devices for Measuring Pupil Diameter in Patients Implanted with Multifocal Intraocular Lenses.

The purpose of this study was to evaluate the agreement between three methods for measuring pupil size in patients implanted with multifocal intraocular lenses (MIOLs): Keratograph 5M (K5M), Pentacam AXL Wave (PW), and a simple hand ruler. Sixty-nine subjects implanted with MIOLs and measured at the three-month follow-up visit were included in this retrospective analysis. K5M and PW were used to measure the photopic (PP) and mesopic (MP) pupil sizes, and a hand ruler was used to measure the pupil under environmental light conditions (135 lux). The Bland-Altman method with its limits (LoAs) was used to assess the agreement. The median PP was 2.8, 2.95, and 3 mm for K5M, PW, and the ruler, respectively (p < 0.05). Differences in PP were statistically significant for all paired comparisons (p < 0.0005) except between PW and the ruler (p = 0.44). The LoAs for the difference in PP between K5M and PW was 0.63 mm. The mean difference for MP between K5M and PW was 0.04 mm (p = 0.34) with LoAs of 0.72 mm. MP measured with K5M and PW could be considered interchangeable, although a correction of -0.3 mm (IC95%: -0.23 to -0.39) should be applied to PP measured with PW to attain the K5M mean.

Efficacy and safety of atropine in myopic children: A meta-analysis of randomized controlled trials

To evaluate the safety and efficacy of atropine for childhood myopia and further explore the optimal concentration of atropine, so as to provide more reference for clinical application. PubMed, Embase, Cochrane Library and ClinicalTrials.gov were comprehensively searched for randomized controlled trials (RCTs) up to October 14, 2021. The efficacy outcomes were progression of spherical equivalent (SE) and axial length (AL). The safety outcomes included accommodation amplitude, pupil size and adverse effects. The meta-analysis was performed using Review Manager 5.3. Eighteen RCTs involving 3002 eyes were included. The results showed that at 6-36months of treatment, atropine was effective in slowing the progression of myopia in children. At 12months, the WMD of SE and AL of low-dose atropine was 0.25diopters (D) and 0.1millimeter (mm), moderate-dose atropine was 0.44D and 0.16mm, high-dose atropine was 1.21D and 0.82mm, respectively, compared with the control group. Similarly, at 24months, low-dose atropine was 0.22D and 0.14mm, moderate-dose atropine was 0.60D, high-dose atropine was 0.66D and 0.24mm, respectively. Interestingly, we also found that there was no significant difference in the effects of low-dose atropine on accommodation amplitude and photopic pupil size compared with the control group, and the rate of photophobia, allergy, blurred vision and other side effects was similar between the low-dose atropine group and the control group. In addition, atropine appears to be more effective in myopic children in China than in other countries. Atropine in various concentrations can effectively slow myopia progression in children, and its effect is dose-dependent, while low-dose atropine (0.01% atropine) appears to be safer.

Improvement in the ideal range of vault after implantable collamer lens implantation: a new vault prediction formula.

To derive and validate a novel vault prediction formula to improve the predictability and safety of implantable collamer lens (ICL) implantation. Thirty-five patients (61 eyes) with previous posterior chamber intraocular lens implantation were included. Various parameters, such as horizontal-visible iris diameter (HVID), photopic pupil diameter (PPD), axial length (AL), white-to-white (WTW), anterior chamber width (ACW), angle-to-angle (ATA), crystalline lens rise (CLR), anterior chamber depth (ACD), horizontal sulcus-to-sulcus (HSTS), and ciliary sulcus angle (CSA) were measured. Vault was measured at 3 months after surgery using CASIA2 anterior segment optical coherence tomography. The formula was derived using multiple linear regression analysis and named as WH formula. It was validated in 65 patients (118 eyes) to determine the percentage of the ideal postoperative vault range and to compare the differences between the WH formula and the NK, KS, and STAAR formulas. Final ICL size, ATA, CSA, and CLR were included in the prediction formula model (adjusted R2 = 0.67, p < 0.001). The achieved vault 1 month after the surgery was 556.19 μm ± 166.98 μm in the validation group, and the ideal vault range was 200-800 μm (92%). The difference between the achieved vault and that predicted using the WH formula was not statistically significant (p = 0.165), whereas the difference between the achieved vault and that predicted using the NK and KS formulas was statistically significant (p < 0.001 and p < 0.001, respectively). The 95% agreement limit range of the achieved vault and the vault predicted using the WH formula was narrower than those predicted using the NK and KS formulas (-295.20-258.82 μm). This study combined the results of optical coherence tomography and ultrasound biomicroscopy measurements of the anterior segment of the eye and incorporated ciliary sulcus morphology quantification into the prediction formula. The study derived a prediction formula for vault by combining ICL size, ATA, and CLR. The derived formula was found to be superior to the currently available formulas.

Light and electron microscopic features of preclinical pseudoexfoliation syndrome.

This study sought to explore the features of the anterior lens capsule in patients with preclinical pseudoexfoliation syndrome (pPEX) via light microscopy (LM) and transmission electron microscopy (TEM). Cross-sectional, prospective, and observational case series. We recruited consecutive patients with and without pPEX who underwent routine cataract surgery at Ramathibodi Hospital, between April 2018 and November 2020. pPEX can be characterized by pigmented spoke-wheel deposition (P) on the anterior lens capsule, midperiphery cleft/lacunae (C), faint central disc present within the photopic pupil (D), white-spoke pattern (W) noted at the midperiphery, and a combination of at least two signs (Co). LM and TEM were used to examine anterior lens capsule specimens for the presence of characteristic pseudoexfoliation material (PXM). The features of the anterior lens capsule in pPEX explored via LM and TEM were recorded. This study included a total of 96 patients (101 excised anterior lens capsules); among them, 34 (35 excised anterior lens capsules) exhibited pPEX signs (pPEX group) but 62 (66 excised anterior lens capsules) did not (control group). The patients had a mean age of 74 ± 7 (range, 58-89) years. LM and TEM revealed no definite PXM in any patient. In the pPEX group, LM analysis identified two capsule specimens with suspected PXM; PXM precursors were observed in 1 of the 34 excised capsule specimens analyzed via TEM. Furthermore, 39 eyes (59.09%) exhibited signs of true exfoliation syndrome (TEX) in LM analysis (12.82%, 25.64%, 10.26%, 10.26%, and 41.03% for patients exhibiting P, D, C, W, and Co, respectively). However, no TEX signs were observed in the control group. We found that the anterior lens capsules exhibiting C and D were significantly associated with TEX (odds ratio = 5.4 and 7.9; P = 0.007 and 0.004, respectively). LM analysis revealed no definite PXMs were detected in the excised anterior lens capsules, whereas TEM analysis showed PXM precursors in one specimen (2.94%). Notably, a significant association was observed between C and D signs and TEX.

How are pupillary parameters affected in pseudoexfoliation syndrome? A quantitative study.

We evaluated the effects of pseudoexfoliation syndrome on dynamic, static pupillary parameters (scotopic, mesopic, photopic) and the pupil dilation speed, with automatic pupillometry. The study group included 140 eyes with clinically visible pseudoexfoliation material (PXM) of 110 patients. The study group was compared with the control group formed by including 140 eyes of 110 patients. Scotopic measurements at 0.4lx illumination, mesopic measurements at 4lx illumination, and photopic measurements at 40lx illumination were performed. Dynamic measurements were made at 500lx illumination. The mean pupil dilation speed at 10th second was calculated. In addition, the eyes (80 patients) with clinically unilateral PXM were compared with the other eyes of the patients. The mean scotopic, mesopic, photopic and dynamic pupil diameters of eyes with clinical PXM were compared with the control group, all values were found to be significantly lower in eyes with PXM. (p < 0.0001, p < 0.0001, p < 0.0001, p < 0.0001, respectively). The mean speed of pupil dilation at the 10th second was also significantly lower in the pseudoexfoliation syndrome group (p < 0.0001). The measurement results of the patients with clinical PXM were significantly lower than the other unaffected eyes (p = 0.001, p = 0.004, p = 0.048, p = 0.035, respectively). The mean speed of pupil dilation at 10th second was also significantly lower in eyes with PXM (p = 0.009). Results clearly reveal that pseudoexfoliation syndrome affects iris mechanisms. Although pseudoexfoliation syndrome is a systemic syndrome, we can say that the emergence of iris dysfunction findings is parallel with the clinical observation of PXM.