Effect of posterior capsule opacification on macular sensitivity

Evaluating the small aperture intraocular lens: depth of focus and the role of refraction and preoperative corneal astigmatism in visual performance

PURPOSE

To evaluate depth of focus (DOF) and visual acuities (VAs) by manifest refractive spherical equivalent (MRSE) and degree of preoperative corneal astigmatism with the IC-8 small aperture intraocular lens (SA IOL) (Apthera).

SETTING

21 investigational sites in the United States.

DESIGN

Prospective, multicenter, open-label, parallel-group, nonrandomized, examiner-masked, 1-year clinical study.

METHODS

Included patients had cataract and ≤1.5 diopters (D) preoperative corneal astigmatism. Patients received either the SA IOL in 1 eye targeted to -0.75 D and a monofocal or monofocal toric IOL in the other targeted to plano (SA IOL group) or bilateral monofocal/monofocal toric IOLs targeted to plano (control group). Monocular and binocular assessments included defocus curves and uncorrected VAs (distance, intermediate, and near) by postoperative MRSE; monocular VAs were assessed by degree of preoperative corneal astigmatism.

RESULTS

The SA IOL group (n = 343) achieved 0.82 D additional binocular DOF vs the control group (n = 110), and SA IOL eyes achieved 0.91 D additional monocular DOF over fellow eyes. Across all MRSEs, the SA IOL group achieved monocular uncorrected VAs of 20/40 or better and binocular uncorrected VAs of 20/32 or better across all distances. In addition, SA IOL eyes with higher (1.0-1.5 D) vs lower (<1.0 D) preoperative corneal astigmatism achieved equivalent monocular uncorrected VAs.

CONCLUSIONS

The SA IOL provides increased DOF vs monofocal/monofocal toric IOLs and consistent monocular and binocular vision across several postoperative MRSEs and up to 1.5 D of preoperative corneal astigmatism, giving patients with cataract and mild astigmatism the potential for an extended range of vision and reliable visual outcomes.

Clinical Comparison of a Small-Aperture Intraocular Lens Versus a Monofocal Control

PURPOSE

To evaluate range of visual acuity, visual quality, and safety of the IC-8 small-aperture (SA) intraocular lens (IOL) (Apthera; Bausch & Lomb, Inc) in patients with cataract.

METHODS

This was a prospective, multicenter, open-label, parallel-group, non-randomized, examiner-masked, 12-month clinical study conducted at 21 sites in the United States. Included patients (N = 453) received either the SA IOL (targeted to -0.75 diopters) in one eye and a monofocal or monofocal toric IOL (targeted to plano) in the fellow eye (SA IOL group, n = 343) or bilateral monofocal/monofocal toric IOLs (control group, n = 110).

RESULTS

At 6 months, the SA IOL group achieved superior binocular uncorrected intermediate and near visual acuity (P < .0001) and equivalent binocular uncorrected distance visual acuity versus the control group. In SA IOL eyes, 99.1% achieved monocular corrected distance visual acuity of 0.3 logarithm of the minimum angle of resolution or better. The SA IOL and control groups had comparable binocular photopic and mesopic contrast sensitivities at 6 months both with and without glare. The SA IOL group reported few visual symptoms overall, although at higher rates than in the control group.

CONCLUSIONS

The SA IOL group exhibited improved intermediate and near vision, comparable distance vision and binocular contrast sensitivities, and few visual symptoms or adverse events versus the bilateral monofocal/monofocal toric IOL group, suggesting that the SA IOL is an effective option for presbyopia correction at the time of cataract surgery. [J Refract Surg. 2024;40(11):e824-e835.].

Two-Photon Microperimetry: A Media Opacity-Independent Retinal Function Assay

Purpose

Compare results obtained using infrared two-photon microperimetry (2PM-IR) with conventional visual function tests in healthy subjects of varying ages with and without simulated media opacities.

Methods

Subjects from two separate cohort studies completed cone contrast threshold (CCT) testing, conventional microperimetry, visible light microperimetry from a novel device (2PM-Vis), and infrared two-photon microperimetry. The first cohort study, which consisted of six healthy volunteers (23 to 29 years of age), evaluated the effects of simulated media opacities on visual performance testing. Subjects underwent testing on four visual function devices nine separate times under the following conditions: no filter, red filter, green filter, blue filter, light brown filter, dark brown filter, polarized black filter (0° rotation), and polarized black filter (90° rotation). Subjects subsequently performed 2PM-IR and 2PM-Vis testing without a filter in the mydriatic state. The second cohort study evaluated the effect of age on visual test performance in 42 healthy subjects split between two groups (ages 20-40 years and 60-80 years).

Results

Retinal sensitivity measured by 2PM-IR demonstrated lower variability than all other devices relying on visible spectrum stimuli. Retinal sensitivity decreased proportionally with the transmittance of light through each filter. CCT scores and retinal sensitivity decreased with age in all testing modalities. Visible spectrum testing modalities demonstrated larger test result differences between young and old patient cohorts; this difference was inversely proportional to the wavelength of the visual function test.

Conclusions

2PM-IR mitigates media opacities that may mask small differences in retinal sensitivity when tested with conventional visual function testing devices.

Translational Relevance

Conventional visual function tests that emit visible light may not detect differences in retinal function during the early stages of age-related diseases due to the confounding effects of cataracts. Infrared light, which has greater transmittance through ocular tissue, may reliably quantify retinal sensitivity and thereby detect degenerative changes early on.

Effect of Cataract Extraction on Retinal Sensitivity Measurements

INTRODUCTION

Central and paracentral retinal function is often compromised in various retinal diseases. In these conditions, microperimetry is an important tool for assessing retinal sensitivity values. As retinal diseases are prevalent among the elderly, cataract often coexists. This study investigates the effect of cataract surgery on retinal sensitivity in patients with cataract without retinal disease.

MATERIAL AND METHODS

A total of 30 patients already scheduled for cataract surgery were enrolled and microperimetry and visual acuity evaluation was performed before and after cataract extraction. The patients were allocated to 1 of 3 study groups in accordance with the main cataract subtype: nuclear, cortical, or posterior subcapsular (PSC) cataract.

RESULTS

Visual acuity increased significantly after cataract surgery (from 0.34 to 0.00 logMar, p < 0.001, paired t test). Similarly, median retinal sensitivity increased significantly from 23 dB (IQR 21-25 dB) to 27 dB (IQR 25.75-28 dB) (p < 0.001, Wilcoxon test). The increase of retinal sensitivity after cataract surgery was highest in the PSC cataract group.

CONCLUSION

This study showed an increase in retinal sensitivity values after cataract removal, especially in the PSC group. Therefore, coexisting cataract should be considered when interpreting microperimetry results.

Fixation characteristics among subjects with diabetes: SN-DREAMS II, Report No. 5

OBJECTIVE

To evaluate fixation and scotoma characteristics among subjects with diabetes in a population-based study.

DESIGN

Cohort study.

PARTICIPANTS

A subset of 357 subjects was recruited from follow-up cohort of Sankara Nethralaya Diabetic Retinopathy Epidemiology and Molecular Genetics Study I.

METHODS

All subjects underwent detailed ophthalmic evaluation including microperimetry and spectral domain optical coherence tomography. Fixation parameters such as stability of fixation, fixation location, and presence of scotoma were evaluated. A p value less than 0.05 was considered statistically significant.

RESULTS

The mean age of the study sample was 56.86 ± 8.63 years. Relatively unstable fixation was observed in 73 and poor central fixation in 25 subjects. Among subjects with poor central fixation, 72% (18 subjects) had relatively unstable fixation. Poor central and relatively unstable fixation were significantly associated with best corrected visual acuity (BCVA; p = 0.002 and p = 0.017, respectively). Prevalence rate of scotoma was 24.4%, which was highly prevalent in females (p = 0.035) and among subjects with reduced BCVA (p < 0.001), reduced contrast sensitivity (p < 0.001), cataract (p < 0.001), impaired retinal sensitivity (p < 0.001), and presence of sight-threatening diabetic retinopathy (STDR; p < 0.001). Presence of scotoma was significantly associated with abnormal foveal contour (p = 0.046) and altered inner retinal layers (p < 0.001).

CONCLUSIONS

We report that fixation characteristics are independent of ocular characteristics except for BCVA. Female sex, reduced visual acuity and contrast sensitivity, cataract, and STDR were significantly associated with presence of scotoma.

Influence of pseudophakic lens capsule opacification on spectral domain and time domain optical coherence tomography image quality

PURPOSE

To evaluate the influence of posterior capsule opacification (PCO) on optical coherence tomography (OCT) acquisition of macular retinal thickness (RT) and volume using time domain OCT (TD-OCT) and spectral domain OCT (SD-OCT).

MATERIALS AND METHODS

We studied 37 eyes of 31 patients with PCO. Each patient underwent an evaluation with TD-OCT and with SD-OCT before and after Nd:YAG capsulotomy. We recorded RT and retinal volume in the macular area using only good quality images.

RESULTS

Best corrected visual acuity improved in all eyes after Nd:YAG capsulotomy, with the degree of improvement ranging from 0.3 ± 0.7 to 0.1 ±0.7 (p = 0.01). Before the treatment, only 27% of the examinations were valuable with TD-OCT, while using SD-OCT, it was possible to obtain an examination of suitable quality both before and after the Yag laser capsulotomy in 100% of the eyes. We did not observe significant differences between mean preoperative and postoperative RT and total macular volume measurements, neither with TD-OCT nor with SD-OCT. RT and total macular volume values obtained using TD-OCT were always lower than those obtained from the SD-OCT, both before and after capsulotomy.

CONCLUSIONS

Our study confirmed that with old generation TD-OCT, PCO has a strong negative influence on the quality of OCT acquisition, and examination is reliable only when it is possible to acquire good quality images. With new generation SD-OCT, tomographic acquisitions are always reliable and are not influenced by the presence of PCO.

Long-term results of phacoemulsification combined with primary posterior curvilinear capsulorhexis in adults

Objective:

To evaluate the 2-year outcomes of phacoemulsification combined with primary posterior curvilinear capsulorhexis (PPCC) in adults.

Materials and Methods:

In this retrospective case series, 93 eyes of 91 patients with bilateral age-related cataract who underwent phacoemulsification combined with PPCC were evaluated. The study included cases due to postoperative residual posterior capsule opacification despite careful polishing. Data were evaluated on preoperative and postoperative best corrected visual acuity (CDVA) (Snellen acuity), slit-lamp biomicroscopy and intraocular pressure (IOP) measurement. Perioperative and postoperative complications were also recorded.

Results:

The mean follow-up was 24.9 ±13.5 months (range, 12-53 months). At the last visit, 87.1% of the eyes had CDVA ≥ 20/40 and 58% had ≥ 20/25. Posterior capsular opacification (PCO) occurred in 2 (2.2%) of patients. No serious complications such as retinal detachment and endophthalmitis were observed during follow-up.

Conclusions:

Cataract surgery combined with PPCC is a safe procedure with a low rate of complications over the long term. This procedure reduced the necessity of Nd:YAG laser capsulotomy in adults with postoperative residual posterior capsule opacification despite careful polishing.

The influence of cortical, nuclear, subcortical posterior, and mixed cataract on the results of microperimetry

PURPOSE

Microperimetry is a useful instrument for evaluating sensitivity threshold due to retinal pathologies. The aim of the study is to assess the impact of different forms of cataract on microperimetry results.

METHODS

In a prospective design, patients were recruited for cataract surgery at the Department of Ophthalmology, Medical University of Vienna. Exclusion criteria were any other ophthalmic disease except cataract, that is, macular pathology. Using the Lens Opacities Classification System III classification, patients were classified into four groups: nuclear, cortical, subcapsular posterior, and mixed cataract. Then patients underwent microperimetry: results were analyzed for magnitude of retinal sensitivity loss and correlated to the forms and density of the cataract.

RESULTS

Mean density of cataract was LOCS 3.2-3.5 in the four groups. Differences were not statistically significant. The best-corrected visual acuity (BCVA) was LogMAR 0.5 ± 0.13 in nuclear, LogMAR 0.49 ± 0.21 in cortical, and LogMAR 0.58 ± 0.12 in mixed cataract patients, and significantly worse in patients with subcapsular posterior cataract (LogMAR 0.64 ± 0.12). Microperimetry shows a mean sensitivity of 11.4-12.6 dB without significant group differences. The BCVA is correlated with microperimetry in patients with nuclear and cortical cataract. Density of cataract is highly correlated with microperimetry results in all groups.

CONCLUSION

The present study shows a good correlation of microperimetry results with the BCVA of patients with nuclear and cortical cataract. In patients with subcapsular posterior cataract, microperimetry results were better than estimated by BCVA. Density of cataract is highly correlated with macular sensitivity. A reduction of 1 dB in microperimetry per 1 posterior capsule opacification score increase can be estimated for these patients.

Three-year follow-up of posterior capsule opacification after AquaLase and NeoSoniX phacoemulsification

PURPOSE

To prospectively compare the degree of posterior capsule opacification (PCO) after AquaLase and NeoSoniX phacoemulsification methods during the 3-year follow-up period.

DESIGN

Prospective, randomized clinical trial.

METHODS

Setting at the Department of Ophthalmology, University Hospital in Hradec Králové. Patients with bilateral cataract were included. AquaLase was used in the right eye and NeoSoniX in the left eye of each patient. The AcrySof SA60AT intraocular lens (Alcon Laboratories, Fort Worth, Texas, USA) was implanted in all eyes. The Evaluation of Posterior Capsule Opacification (EPCO) 2000 software (Developed by Tetz MR and associates, Berlin, Germany) and the Open-Access Systematic Capsule Assessment (OSCA) system (Devised by Aslam TM, Edinburgh, United Kingdom) were used for PCO assessment 1, 2, and 3 years after cataract surgery.

RESULTS

Fifty patients were analyzed 1 year, 47 patients 2 years, and 46 patients 3 years after cataract surgery. Mean EPCO 2000 values were for the AquaLase group 0.324 +/- 0.305 and for the NeoSoniX group 0.298 +/- 0.341 (P = .53) 1 year after surgery, for the AquaLase group 0.429 +/- 0.322 and for the NeoSoniX group 0.478 +/- 0.337 (P = .30) 2 years after surgery, and for the AquaLase group 0.582 +/- 0.506 and for the NeoSoniX group 0.594 +/- 0.515 (P = .87) 3 years after surgery. The OSCA results were for the AquaLase group 0.7097 +/- 0.3778 and for the NeoSoniX group 0.8584 +/- 0.4323 (P = .046) 1 year after surgery, for the AquaLase group 0.7515 +/- 0.4555 and for the NeoSoniX group 0.8103 +/- 0.4498 (P = .44) 2 years after surgery, and for the AquaLase group 0.9667 +/- 0.736 and for the NeoSoniX group 0.9540 +/- 0.5250 (P = .91) 3 years after surgery. Neodymium-yttrium-aluminun-garnet capsulotomy rate for AquaLase vs NeoSoniX was 0:1 eyes 1 year, 1:3 eyes 2 years, and 1:4 eyes 3 years after surgery. No significant difference between those 2 groups was established, except the OSCA outcomes 1 year postoperatively.

CONCLUSION

There was only minimal PCO difference between these 2 approaches, AquaLase and NeoSoniX. Neither AquaLase nor NeoSoniX technique was able to prevent a natural progression of PCO.