Pseudophakic Eyes Research Articles

Visual Acuity and Ophthalmic Outcomes 5 Years After Cataract Surgery Among Children Younger Than 13 Years

Cataract is an important cause of visual impairment in children. Data from a large pediatric cataract surgery registry can provide real-world estimates of visual outcomes and the 5-year cumulative incidence of adverse events. To assess visual acuity (VA), incidence of complications and additional eye operations, and refractive error outcomes 5 years after pediatric lensectomy among children younger than 13 years. This prospective cohort study used data from the Pediatric Eye Disease Investigator Group clinical research registry. From June 2012 to July 2015, 61 eye care practices in the US, Canada, and the UK enrolled children from birth to less than 13 years of age who had undergone lensectomy for any reason during the preceding 45 days. Data were collected from medical record reviews annually thereafter for 5 years until September 28, 2020. Lensectomy with or without implantation of an intraocular lens (IOL). Best-corrected VA and refractive error were measured from 4 to 6 years after the initial lensectomy. Cox proportional hazards regression was used to assess the 5-year incidence of glaucoma or glaucoma suspect and additional eye operations. Factors were evaluated separately for unilateral and bilateral aphakia and pseudophakia. A total of 994 children (1268 eyes) undergoing bilateral or unilateral lensectomy were included (504 [51%] male; median age, 3.6 years; range, 2 weeks to 12.9 years). Five years after the initial lensectomy, the median VA among 701 eyes with available VA data (55%) was 20/63 (range, 20/40 to 20/100) in 182 of 316 bilateral aphakic eyes (58%), 20/32 (range, 20/25 to 20/50) in 209 of 386 bilateral pseudophakic eyes (54%), 20/200 (range, 20/50 to 20/618) in 124 of 202 unilateral aphakic eyes (61%), and 20/65 (range, 20/32 to 20/230) in 186 of 364 unilateral pseudophakic eyes (51%). The 5-year cumulative incidence of glaucoma or glaucoma suspect was 46% (95% CI, 28%-59%) in participants with bilateral aphakia, 7% (95% CI, 1%-12%) in those with bilateral pseudophakia, 25% (95% CI, 15%-34%) in those with unilateral aphakia, and 17% (95% CI, 5%-28%) in those with unilateral pseudophakia. The most common additional eye surgery was clearing the visual axis, with a 5-year cumulative incidence of 13% (95% CI, 8%-17%) in participants with bilateral aphakia, 33% (95% CI, 26%-39%) in those with bilateral pseudophakia, 11% (95% CI, 6%-15%) in those with unilateral aphakia, and 34% (95% CI, 28%-39%) in those with unilateral pseudophakia. The median 5-year change in spherical equivalent refractive error was -8.38 D (IQR, -11.38 D to -2.75 D) among 89 bilateral aphakic eyes, -1.63 D (IQR, -3.13 D to -0.25 D) among 130 bilateral pseudophakic eyes, -10.75 D (IQR, -20.50 D to -4.50 D) among 43 unilateral aphakic eyes, and -1.94 D (IQR, -3.25 D to -0.69 D) among 112 unilateral pseudophakic eyes. In this cohort study, development of glaucoma or glaucoma suspect was common in children 5 years after lensectomy. Myopic shift was modest during the 5 years after placement of an intraocular lens, which should be factored into implant power selection. These results support frequent monitoring after pediatric cataract surgery to detect glaucoma, visual axis obscuration causing reduced vision, and refractive error.

Anatomical and functional outcomes of pneumatic vitreolysis for treatment of vitreomacular traction with and without macular holes

PurposeTo evaluate the outcome of pneumatic vitreolysis (PVL) for vitreomacular traction (VMT) with or without full thickness macular hole (MH) < 400 µm.MethodsForty-seven eyes of 47 patients were included who had undergone PVL for VMT with or without MH. Main outcome measures were release of VMT, MH closure, best-corrected visual acuity (BCVA) and adverse events.ResultsThirty-three patients had isolated VMT and 14 patients VMT with a MH. Four weeks after PVL, the overall VMT release rate was 35/47 (74.5%): 25/37 (67.6%) in phakic and 10/10 (100%) in pseudophakic eyes (p = 0.03). Four of 14 MH (28.6%) were closed. Twenty-two of 47 (46.8%) eyes required a subsequent PPV: 12/33 (36.4%) in the VMT only group and 10/14 (71.4%) in the VMT with MH group. Mean BCVA improved from 0.48 (± 0.24) to 0.34 (± 0.23) logMAR at 6 months in patients with VMT alone (p < 0.001), and from 0.57 (± 0.27) to 0.41 (± 0.28) logMAR in patients with VMT and MH (p = 0.008). Adverse events included new formation of a large MH in 4/33 (12.1%) eyes, failure of MH closure in 10/14 (71.4%) eyes, progression of mean minimum linear diameter (MLD) MH size from baseline 139 (± 67) to 396 (± 130) µm (p < 0.001) and development of a retinal detachment in 4/47 (8.5%) eyes.ConclusionWhile PVL leads to a high VMT release rate particularly in pseudophakic eyes, it is associated with a relatively high incidence of MH formation, MH size progression and retinal detachment.

Five-year follow-up of corneal morphology and corneal refractive power changes after uneventful DMEK.

To investigate changes of corneal thickness spatial profile (CTSP), corneal volume (CV) distribution, and total corneal refractive power (TCRP) over a course of 60months after uneventful Descemet membrane endothelial keratoplasty (DMEK). In our prospective, comparative study, sixty DMEK cases without intraoperative and postoperative complications and with complete 60-month follow-up were included (group 1). CTSP at corneal apex (CCT) and at 2mm, 4mm, 6mm, and 8mm rings, CV in 3mm, 5mm, 7mm, and 10mm zones, and TCRF in 2mm, 4mm 6mm, and 8mm zones were evaluated preoperatively and at 3, 6, 12, 24, and 60months postoperatively. The 60-month results were compared to an age-matched group of uncomplicated pseudophakic eyes (group 2; n = 20). The CCT and CTSP at 2, 4, and 6mm increased significantly at 60months compared to 3-month outcomes (P < 0.001). Similarly, CV increased significantly in 3mm, 5mm, and 7mm zones at 60months compared to 3months outcomes (P < 0.001). The TCRP showed in all zones a significant decrease at 3months (P < 0.001) followed by a continuous and significant increase at 60months (P < 0.001). The 60-month CCT and CTSP at 2mm were similar to group 2 (P ≥ 0.094). Sixty months after uneventful DMEK, CT within the central 2mm zone and CV at 3mm zone were similar to uncomplicated pseudophakic eyes. A continuous and statistically significant increase of TCRP was observed in all measured zonesafter the 3-month examination.

Visual Function in Pseudophakic Eyes with Fuchs’ Endothelial Corneal Dystrophy

To assess vision in pseudophakic eyes with Fuchs' endothelial corneal dystrophy (FECD) before the onset of clinically detectable corneal edema. Cross-sectional study. Sixty-one otherwise healthy pseudophakic eyes of 38 subjects with FECD (without clinically detectable edema) and 17 otherwise healthy pseudophakic eyes of 9 subjects with normal corneas. Subjects underwent clinical examination to determine the morphologic distribution of guttae (severity grading). Standardized best-corrected high-contract and low-contrast (photopic and mesopic) visual acuity (HCVA, LCVA) and straylight were measured. Scheimpflug tomography posterior elevation and pachymetry maps were interpreted for 3 tomographic features of subclinical edema: loss of regular isopachs, displacement of the thinnest point of the cornea, and presence of posterior surface depression. In FECD without tomographic features of edema (ie, normal tomography patterns), HCVA, LCVA, and straylight did not differ from that of eyes with normal corneas (P ≥ .09); these eyes encompassed the full range of severity grading of guttae. In FECD with all 3 tomographic features of edema, the same parameters were worse compared with eyes with normal corneas (P ≤ .02). In FECD with 1 or 2 tomographic abnormalities, mesopic LCVA (P=.04) and straylight (P=.003) were worse compared with eyes with normal corneas. Impairment of vision was associated with the presence of tomographic edema in eyes with FECD. When tomography patterns were normal in FECD (ie, guttae were present without tomographic edema), visual acuity and straylight were normal, and therefore corneal surgical intervention would not typically be indicated to improve vision.

Effect of Blue Light–Filtering Intraocular Lenses on Insomnia After Cataract Surgery: A Nationwide Cohort Study With 10-Year Follow-up

To compare the incidence of clinically diagnosed insomnia after cataract surgery in pseudophakic eyes with blue light-filtering intraocular lenses (BF-IOLs) and non-BF-IOLs. Nationwide cohort study using the Taiwan National Health Insurance Research Database. We enrolled 171,415 patients who underwent cataract surgery in both eyes between 2008 and 2013 and followed them till 2018. Propensity score matching (PSM) was used to balance the baseline characteristics between the 2 IOL groups. The Cox model and cause-specific hazard model were used to estimate the hazard ratios (HRs) and subdistribution hazard ratio (SHR). Overall, 19,604 (11.4%) and 151,811 (88.6%) patients had BF-IOL and non-BF-IOL implants, respectively. The BF-IOL group tended to be younger and had fewer chronic diseases. Within a mean follow-up period of 6.2 years, the incidence rates of insomnia (per 100 person-years) in the BF-IOL and non-BF-IOL groups were 2.97 and 3.21, respectively. There was no significant difference in the incidence rate of insomnia between the 2 IOL groups after treating all-cause mortality as a competing risk (SHR 0.98, 95% CI 0.95-1.01) and after PSM (HR0.97, 95% CI0.92-1.01), respectively. Subgroup analysis revealed no significant difference in the insomnia rate between the 2 IOL groups for various age groups, 2 sex groups, and men with and without benign prostatic hyperplasia. In Taiwan, the use of a BF-IOL for up to 10 years had no apparent disadvantage over non-BF-IOLs with respect to insomnia.

Predictability of success and open conjunctival revision rates in the subsequent eye after XEN45 Gel Stent implantation according to lens status

PurposeTo determine the predictability of success and the risk of open conjunctival revision in the subsequent eye after XEN45 Gel Stent implantation according to lens status.MethodsThis was a retrospective single-centre study involving 132 eyes of 66 participants who had undergone intraocular pressure (IOP)-lowering XEN45 Gel Stent implantation, either as a standalone procedure in phakic and pseudophakic eyes or in combination with phacoemulsification. Successful surgery was defined by three scores: IOP at follow-up < 21 mmHg (score A) or < 18 mmHg (score B) and an IOP reduction > 20% or IOP ≤ 15 mmHg and an IOP reduction ≥ 40% (score C). In all scores, one open conjunctival revision was allowed, and additional repeat surgery was considered a failure. The predictability of success and revision rate depending on the outcome of the first eye were calculated using Bayes’ theorem.ResultsIOP-lowering did not differ significantly between the first and second eyes. Success rates of standalone surgery in the second eye after successful surgery in the first eye significantly exceed rates after prior failure. For the combined procedure, the rates did not differ significantly. For score A, we determined a 76.6% chance of success following a prior success and a 57.9% chance, if prior surgery failed. The corresponding probabilities were 75% and 59.1% for score B, while 66.7% and 15.7% for score C, respectively. We calculated a 60% risk for revision surgery in the standalone phakic group. If the first eye was not revised, the risk of revision in the subsequent eye was 20%. The corresponding risks were 72.7% and 5% for the standalone procedure in pseudophakic patients and 38.4% and 41.7% for the combined procedure, respectively.ConclusionThe results of our study offer a tool to predict the outcome of subsequent eye surgeries based on either the outcome in the initial eye and the type of surgery performed, owing to the high predictive potential.

Posterior Chamber Intraocular Lens Dislocation Into the Vitreous in Association With Descemet Stripping Lamellar Keratoplasty

The purpose of this study was to report 3 cases of a single-piece, acrylic, foldable, modified C loop posterior chamber intraocular lens (PCIOL) dislocated into the vitreous cavity after Descemet stripping automated endothelial keratoplasty (DSAEK). We describe the clinical course and management of the 3 cases in which a previously implanted foldable, single-piece, acrylic posterior chamber intraocular lens with modified C loops dislocated into the vitreous in association with DSAEK. Surgical management consisted of pars plana vitrectomy in each case with either PCIOL repositioning (2 cases) or PCIOL exchange (1 case) and with different fixation methods, combined with repeated DSAEK in 1 case with previous primary graft failure. In 2 cases where the cornea cleared after the DSAEK, the cornea kept its clarity and the PCIOL remained stable. In the third case in which the PCIOL exchange was combined with DSAEK, the cornea only partially cleared up, both the PCIOL and the state of the eye remained stable. PCIOL dislocation is a possible and notable complication that requires attention while performing DSAEK on pseudophakic eyes. Not only plate-haptic silicone but also acrylic, single-piece PCIOLs with modified C loops may dislocate into the vitreous in association with DSAEK in cases with compromised capsular or zonular integrity.

Outcome of Trabeculectomy in Phakic and Pseudophakic Eyes with Open Angle Glaucoma after Phacoemulsification: A retrospective Comparative Study

Outcome of Trabeculectomy in Phakic and Pseudophakic Eyes with Open Angle Glaucoma after Phacoemulsification: A retrospective Comparative Study

Efficacy of pars plana vitrectomy (PPV) for visually significant vitreous opacities.

Objective: To study the efficacy of pars plana vitrectomy (PPV) for visually significant vitreous opacities in improving visual function and quality of life. Study Design: Interventional study. Setting: Department of Vitreoretinal Clinic of Ophthalmology, Nishtar University Hospital Multan. Period: May 2017 to August 2019. Material &amp; Methods: A total of 50 patients of both genders, aged 35 to 65 years having lenticular status (Phakic or pseudophakic patients) and planned for PPV were enrolled for this study. All patients were examined on slit lamp bio microscope. Dilated fundus examination was performed with indirect ophthalmoscope using scleral indentation. Intraocular pressure was measured pre and postoperatively with Goldmann’s applanation tonometer under topical anaesthesia. Diagnosis was made on through clinical examination. All patients underwent 23 gauge PPV with or without silicon oil with endo laser. Best spectacle corrected visual acuity was recorded with help of Snellen chart. Results: There were 50 eyes of 50 patients in two groups, 40 phakic eyes (80%) and 10 pseudophakic eyes (20%) that underwent 3 PPV for visually significant opacities. There were 38 (76.0%) male and 12 (24.0%) female patients. Thirty four (68.0%) out of 50 patients showed improved best spectacle corrected visual acuity (BSCVA) and visual function while 18% had BCVA 6/24 – 6/18. Forty three (86.0%) patients reported quality of life and psychological feel improvement. Conclusion: Pars plana vitrectomy is a safe, effective and viable option for annoying vitreous floaters. There are risks of retinal breaks, rhegmatogenous retinal detachment and cataract. Surgeon must be ready for prompt handling of patient.

Visual outcomes after vitrectomy for epiretinal membrane in pseudophakic eyes with a diffractive trifocal intraocular lens: a retrospective cohort study

BackgroundDiffractive intraocular lenses (IOLs) could affect visual acuity in patients with macular pathologies such as epiretinal membrane (ERM) and could influence the results of pars plana vitrectomy (PPV) for ERM removal in pseudophakic eyes with these IOLs. The aim of this study is to evaluate the effect on visual outcomes of a diffractive trifocal IOL in PPV for ERM peeling.MethodsThis is a retrospective cohort study on 20 eyes with a single model of trifocal IOL that underwent PPV for removal of ERM between January 2015 and September 2018 in our clinics. Follow up was at least 1 year. Primary outcome measure was mean change in visual acuity. Secondary outcome measures were mean change in central macular thickness (CMT), recovery of the external retinal layers, and change in spherical equivalent (SE).ResultsMean corrected distance visual acuity (CDVA) was 0.03 ± 0.03 logMAR after phacoemulsification; this worsened to 0.23 ± 0.10 logMAR with ERM, improving to 0.10 ± 0.04 log MAR 12 months after PPV (p = 0.001). Mean uncorrected near visual acuity (UNVA) was Jaeger 2.62 ± 0.51 after lensectomy. This worsened to Jaeger 5.46 ± 1.67 with ERM and improved to the initial Jaeger 2.69 ± 0.84 after PPV (p = 0.005). CMT decreased significantly, from 380.15 ± 60.50 μm with the ERM to 313.70 ± 36.98 μm after PPV. Mean SE after lensectomy was − 0.18 ± 0.38 D, which minimally changed to – 0.18 ± 0.47 D after PPV (p = 0.99). The only complication recorded after PPV was a case of cystoid macular edema. No difficulties in visualization due to IOL design were reported during PPV.ConclusionPPV for ERM in eyes with this trifocal IOL seems to be safe and effective, and allows recovery of the loss of UNVA.

Type of residual astigmatism and uncorrected visual acuity in pseudophakic eyes

It is difficult to assess the pure impact of the type of residual astigmatism (with-the-rule; WTR, against-the-rule; ATR, and oblique astigmatism) on uncorrected distance visual acuity (UDVA) in pseudophakic eyes due to different age distribution of patients between those subgroups. We conducted the current study to investigate the association between astigmatism type and UDVA in eyes after cataract surgery with consideration for various confounding factors such as age. Data were retrospectively collected from 1535 pseudophakic eyes with corrected distance visual acuity (CDVA) of 20/20 or better, and spherical equivalent between − 0.125 D and 0.0 D. They were classified based on the pattern of residual refractive astigmatism into four groups; minimum astigmatism (< 0.5 D), WTR, ATR, and oblique astigmatism groups. The stepwise multivariate regression analysis showed that the magnitude of residual refractive astigmatism (standardized partial regression coefficient β = 0.559, p < 0.001), CDVA (β = 0.381, p < 0.001), minimum astigmatism group (β = − 0.188, p < 0.001), and WTR astigmatism group (β = − 0.058, p < 0.001) were significantly associated with UDVA (r2 = 0.795). Variables excluded from the multivariate regression model include age, preoperative corneal astigmatism, axial length, anterior chamber depth, intraocular lens power, and postoperative spherical equivalent. These results indicate that UDVA is significantly better in eyes with minimum and WTR astigmatism than in those with ATR and oblique astigmatism, after adjustment for confounding parameters. In pseudophakic eyes, oblique and ATR astigmatism exerts a greater impact on UDVA than WTR astigmatism does, even after controlling for age.

A Randomized Trial Comparing Suprachoroidal and Intravitreal Injection of Triamcinolone Acetonide in Refractory Diabetic Macular Edema due to Epiretinal Membrane.

Purpose To compare the efficacy and safety of suprachoroidal and intravitreal injection of triamcinolone acetonide in pseudophakic patients with refractory diabetic macular edema (DME) due to epiretinal membrane (ERM). Study Design. This study is a randomized clinical trial (RCT). Participants. Twenty-three nonvitrectomized pseudophakic eyes of 23 subjects (9 M and 14 F with mean age: 54.8 years) with refractory DME due to ERM. Methods The eyes were randomized to suprachoroidal triamcinolone acetonide injection 4 mg/0.1 ml (SCTA) (n = 13 eyes) or intravitreal triamcinolone acetonide 4 mg/0.1 ml (IVTA) (n = 10 eyes) and were evaluated at baseline and 1 and 3 months after injection to assess outcome measures. Main Outcome Measures. Changes in best-corrected visual acuity (BCVA) (primary outcome), central foveal thickness (CFT) by optical coherence tomography (OCT), and intraocular pressure (IOP) measurement (secondary). Results Baseline median BCVA (logMAR) was 1.0 (range 0.8–1.0) in both groups, improved within the SCTA group to 0.8 on the 1st and 3rd months, while in the IVTA group, median BCVA changed to 0.8 and 0.9 on the 1st and 3rd months, respectively. No significant differences were noted between groups regarding BCVA at baseline (P=0.927), and 1st (P=0.605) and 3rd months (P=0.313). Regarding mean CFT, no significant differences were observed at baseline (P=0.353) and at the first month (P=0.214) between both groups, while at the third month, CFT was significantly higher in the IVTA group (385 um) than in the SCTA group (323 um) (P=0.028). Mean IOP was significantly higher in the IVTA group (15 mmHg) on 1st month than in the SCTA group (12 mmHg) (P=0.011); after 3rd month, IOP was significantly higher within the IVTA group (18 mmHg) than SCTA (14 mmHg) (P=0.028). No significant difference was noted between both groups at baseline IOP (P=0.435). Conclusions Both SCTA and IVTA are effective in reduction of CFT and improvement of patients' visual acuity, but with a higher recurrence rate and rise in IOP after IVTA when compared to SCTA. Both treatments have temporary effects with the possibility of recurrence of DME and the need for retreatment.

Simulation of photic effects after cataract surgery for off-axis light sources.

Photopsia is a phenomenon that sometimes disturbs patients after cataract surgery. To evaluate the impact of the edge design of intraocular lenses (IOL) on the location, shape and relative intensity of photic effects at the retina caused by photopsia in pseudophakic eyes, photopsia was simulated using ZEMAX software. The structural parameters of the pseudophakic eye model are based on the Liou-Brennan eye model parameters with a pupil diameter of 4.5 mm. The IOLs implanted in the eye model have a power of 21 diopter (D) with optical diameter of 6 mm and 7 mm. From the ray-tracing analysis, covering variations of incident ray angle of 50° to 90° from temporally, a photic image is detected at the fovea at specific ray angles of 77.5° (6 mm IOL) and 78.2° (7 mm IOL). This photic image disappears when a thin IOL with an edge thickness of 0 mm or a thick IOL with absorbing edges is replaced in the eye model. With an anti-reflective edge, this photic image remains, but with a fully reflecting edge it disappears at the critical angles and appears with different shapes at other angles. The intensity of this photic image can be reduced by changing the edge design to a frosted surface. Most of the photic patterns in IOLs are not observed with absorbing and thin edge designs. IOLs with anti-reflecting and fully reflecting edges generate disturbing photic effects at different angles on the fovea. IOLs with frosted edges reduce the contrast of the photic effects and make them less disturbing for patients.

A GEE model for predicting axial length after cataract surgery in children younger than 2years of age.

To develop a model for predicting postoperative axial length (AL) in children undergoing cataract surgery younger than 2years of age. The Eye Hospital of Wenzhou Medical University, Hangzhou, China DESIGN: Retrospective study. Children were included only if AL data were available before surgery and at least 1year after surgery. Eyes were divided into pseudophakic, aphakic, and unaffected eye groups. Variables that could influence axial growth were analyzed and a multivariable generalized estimating equation regression model was developed to predict postoperative AL. 333 eyes from 190 patients were included. We observed a logarithmic linear correlation between age and AL in the unaffected eye group, AL = (2.7924 × log of age in months) + 17.607, R2 = 0.6596. Meanwhile, The GEE model of eyes with cataracts can be written as follows: Postoperative AL = 6.408 + 0.611 × (baseline AL) + 0.007 × (baseline age) - -0.006 (baseline age) × (age at follow-up) - -0.391 × coefficient of surgery. The ages were recorded in months, the ALs were recorded in millimeter. The assessment of AL is one of the most important parts of successful postoperative management in congenital cataract patients. This study established an AL estimate formula for children aged ≤ 2years with congenital cataract who underwent cataract surgery. This model theoretically could be used to predict individual future AL for child undergoing cataract surgery.

Development and Verification of an Adjustment Factor for Determining the Axial Length Using Optical Biometry in Silicone Oil-Filled Eyes.

The aim of this prospective clinical study was to establish and verify an adaptation for axial length (AL) measurement in silicone oil (SO)-filled pseudophakic eyes with a Scheimpflug and partial coherence interferometry (PCI)-based biometer. The AL was measured with a Pentacam AXL (OCULUS Optikgeräte GmbH, Wetzler, Germany) and IOLMaster 700 (Carl Zeiss Meditec, Jena, Germany). The coefficients of variation (CoV) and the mean systematic difference (95% confidence interval (CI)) between the devices were calculated. After implementing a setting for measuring AL in tamponaded eyes with a Pentacam based on data of 29 eyes, another 12 eyes were examined for verification. The mean AL obtained with the Pentacam was 25.53 ± 1.94 mm (range: 21.70 to 30.76 mm), and with IOLMaster, 24.73 ± 1.97 mm (ranged 20.84 to 29.92 mm), resulting in a mean offset of 0.80 ± 0.08 mm (95% CI: 0.77, 0.83 mm), p < 0.001. The AL values of both devices showed a strong linear correlation (r = 0.999). Verification data confirmed good agreement, with a statistically and clinically non-significant mean difference of 0.02 ± 0.04 (95% CI: −0.01, 0.05) mm, p = 0.134. We implemented a specific adaptation for obtaining reliable AL values in SO-filled eyes with the Pentacam AXL.

The influence of mild posterior capsular opacification on spectral domain optical coherence tomography retinal nerve fiber layer thickness.

Τo investigate whether Yag laser capsulotomy, in addition to restoring ocular media transparency, may also significantly alter retinal nerve fiber layer (RNFL) thickness analysis and spectral domain optical coherence tomography (SD OCT) indices and quality parameters, such as signal strength (SS), in patients with mild, diffuse posterior capsular opacification (PCO). Prospective interventional case series study which enrolled 28 patients with mild PCO and good baseline best-corrected visual acuity (BCVA). All patients underwent a complete ophthalmologic examination, including SD OCT RNFL thickness measurement prior to Yag laser capsulotomy. Following laser intervention, all patients repeated the same complete ophthalmic examination and results were recorded and analysed. Mean RNFL thickness showed a significant postoperative increase from 89.6 to 94.1μm (p = 0.01), which was also confirmed for superior (p = 0.041), nasal (p = 0.011) and inferior quadrants (p = 0.032). SS and BCVA were also significantly increased after laser treatment (p < 0.01). A significant positive correlation was observed between SS and mean RNFL thickness postoperatively (p = 0.043) but not preoperatively (p = 0.059). Similarly, a significant relationship was found between BCVA and average RNFL thickness after (p = 0.017) but not before (p = 0.457) laser intervention. Our study suggests that the presence of even mild PCO may alter the sensitivity of SD-OCT acquisition and lead to inadvertent RNFL thickness underestimation. Clinicians should be alerted to this contingency and take it into consideration when evaluating various optic neuropathies with SD OCT, in pseudophakic eyes.

Macular Morphologic and Microvascular Analysis in Pseudophakic Children with Previous Pediatric Cataract Using Optical Coherence Tomography Angiography

Introduction: The macular morphologic and microvascular changes in children with pseudophakia after pediatric cataract surgery remain unknown. The aim of this study was to analyze macular morphologic and microvascular remodeling in children with pseudophakia after pediatric cataract surgery using optical coherence tomography angiography (OCTA). Methods: Consecutive cases between December 1, 2018, and November 31, 2020 were recruited. Sixty-one participants (31 pseudophakic children and 30 healthy controls) met the inclusion criteria and were included for final analysis. OCTA was used to measure macular vascular density, the foveal avascular zone (FAZ), and macular thickness. The parameters were compared between pseudophakic and healthy eyes using binary logistic regression, with adjustment for the effect of refractive error, age, and axial length. Results: Compared with normal eyes, a significantly reduced area of the FAZ (p = 0.042), increased superficial foveal vascular density (p = 0.033), and increased inner and outer foveal thickness (p = 0.034 and 0.029, respectively) were noted in pseudophakic eyes. The deep parafoveal vascular density was generally lower in eyes with cataracts (p ≤ 0.044). The inner foveal thickness was positively correlated with the superficial foveal vascular density (r = 0.889, p < 0.001) and negatively correlated with the area of the FAZ (r = −0.903, p < 0.001). The outer foveal thickness was positively correlated with the deep foveal vascular density (r = 0.399, p = 0.002). Conclusions: Morphological and microvascular remodeling in children with previous pediatric cataract indicates foveal underdevelopment. The underlying mechanism requires further investigation.

IS A DECREASED NITRIC OXIDE CONCENTRATION AFTER TRIAMCINOLONE ACETONIDE INTRAVITREAL INJECTION ONE OF THE REASONS FOR INTRAOCULAR PRESSURE RISE?

Diabetic macular edema is the most common cause of vision loss in patients affected by diabetes mellitus. For eyes with persistent retinal thickening despite anti-VEGF therapy, treatment with intravitreal triamcinolone may be considered, especially in pseudophakic eyes. The aim of this study was to examine aqueous humor nitric oxide concentration changes in pseudophakic eyes with persistent diffuse diabetic macular edema after intravitreal injection of triamcinolone acetonide, as well as the potential impact of these changes on the intraocular pressure values. In 10 pseudophakic eyes with persistent diffuse diabetic macular edema, paracentesis of anterior chamber with aspiration of aqueous humor and nitric oxide concentration measurements were done on the day of the intravitreal application of 20 mg triamcinolone acetonide, and after 1, 3, 6 and 9 months. Also, we were recording intraocular pressure values before the intravitreal triamcinolone acetonide injection and during the next 9 months. One month after the intravitreal triamcinolone acetonide injection, we noticed a decrease of nitric oxide concentration (45.37±5.55 µmol/L) by 31.79% compared to the initial values (66.52±7.66 µmol/L). After that, nitric oxide concentrations began to rise slightly, and at the end of the ninth month the mean nitric oxide concentration was similar to that recorded at the beginning of the study. Intraocular pressure values had increasing trend one month after the intravitreal triamcinolone acetonide injection (23.70±4.08 mm Hg) compared to the initial values (16.21±1.55 mm Hg), but after nine months these values returned to normal levels. Decreased concentration of nitric oxide could be one of the reasons for increased intraocular pressure after intravitreal application of triamcinolone acetonide in the treatment of diffuse diabetic macular edema.

Calculation of Equivalent and Toric Power in AddOn Lenses Based on a Monte Carlo Simulation

Introduction: Additional lenses implanted in the ciliary sulcus (AddOn) are one option for permanent correction of refractive error or generate pseudoaccommodation in the pseudophakic eye. The purpose of this paper was to model the power and magnification behaviour of toric AddOn and to show the effect sizes with a Monte Carlo simulation. Methods: Anonymized data of a cataractous population uploaded for formula constant optimization were extracted from the IOLCon platform. After filtering out data with refractive spherical equivalent (RSEQ) between −0.75 and 0.25 dpt and refractive cylinder (RCYL) lower than 0.75, for each of the N = 6,588 records, a toric AddOn was calculated which transfers the refraction error from spectacle plane to AddOn plane using a matrix-based calculation strategy based on linear Gaussian optics. The equivalent (AddOnEQ) and toric (AddOnCYL) power of the AddOn and the overall lateral magnification change and meridional magnification were derived for the situations before and after AddOn implantation, and a linear modelling was fitted for all 4 parameters. Results: RSEQ is the dominant effect size in the prediction of AddOnEQ and overall change in magnification (ΔM), whereas the lens position (LP), corneal thickness (CCT), and mean corneal radius (CP_a) play a minor role. In a simplified model, AddOnEQ can be estimated by 0.0179 + 1.4104 RSEQ. RCYL and corneal radius difference (CP_ad) are the dominant effect sizes in the prediction of AddOnCYL and the change in meridional magnification (ΔM_mer), whereas LP, CCT, CP_a, and RSEQ play a minor role. In a simplified model, AddOnCYL can be predicted by −0.0005 + 0.0328 CP_ad + 1.4087 RCYL. Myopic eyes gain in overall magnification, whereas in hyperopic eyes, we observe a loss. Meridional distortion could be in general reduced to 35% on average with a toric AddOn. Conclusion: Our simulation shows that with a linear model, the equivalent and toric AddOn power, as well as overall change in magnification, meridional distortion before and after AddOn implantation, and the reduction in meridional distortion, can be easily predicted from the biometric data in pseudophakic eyes with moderate refractive error.

Prevalence and Association of Meibomian Gland Dysfunction with Dry Eye Severity from a Tertiary Care Rural Hospital in Central Gujarat: A Cross-sectional Study

Introduction: Meibomian glands are holocrine meibum secreting glands driving out the oil from the orifice. It forms the outermost lipid layer of the tear film which prevents overflow of tears because of its hydrophobic properties and reduces their evaporation. The deficiency of oily layer of the tear film leads to evaporative dry eyes and ocular surface diseases. As Meibomian Gland Dysfunction (MGD) is one of the major causes of evaporative dry eye, with the help of this study, prevalence and association of MGD and dry eye can be evaluated and treated. Aim: To find out the prevalence and association of MGD and dry eye as well as asymptomatic individuals having MGD and dry eye in 30-80 years age group in the region of central Gujarat, Western India. Materials and Methods: This cross-sectional study was conducted in the Out Patient Department (OPD) of a Rural Tertiary care hospital in central Gujarat, India between February 2020- February 2021, after taking approval from Institutional Ethics Committee. Study included 389 subjects representing rural population of Anand, Gujarat, India. Subjects were asked for symptoms of dry eye according to Ocular Surface Disease Index (OSDI) questionnaire and severity of symptoms was assessed. Comprehensive ophthalmic examination including Best Corrected Visual Acuity (BCVA), Schirmer’s test, slit lamp examination including conjunctival and corneal surface staining, Tear Film Break Up Time (TBUT), evaluation of meibomian gland orifices, lid margin anatomy, meibum expressibility, quality of meibum, meibomian gland dropouts was done. On the basis of these parameters, diagnosis and grading of MGD and dry eye was done. Subgroups were made according to age, gender, comorbidities (diabetes mellitus, hypertension, thyroid disease), cases of any refractive eye surgery, pseudophakic eyes, use of systemic drugs, hormonal pills, topical antiglaucoma drugs and use of contact lens. Data analysis was done by descriptive statistics (using Stata software 14.2 version). Analysis of Variance (ANOVA) were used to assess the association and Pearson test was applied to assess the correlation of MGD scores and dry eye severity with age. Results: Overall prevalence of MGD and dry eye were 97.4 % and 88.82% respectively. Out of all, 219 (56.3%) participants were asymptomatic. Age was significantly correlated with MGD and dry eye severity. Higher MGD scores were found with increase with dry eye severity. Highest MGD scores were observed when the tear break up time was &lt;5 seconds. Conclusion: The prevalence of MGD and dry eye was high in the region of central Gujarat, India. MGD leads to deficiency of oily layer of the tear film leading to evaporative dry eyes and ocular surface diseases.