Using Optical Quality Analysis System for predicting surgical parameters in age-related cataract patients

Abstract

The Optical Quality Analysis System (OQAS, Visiometrics) provides objective measurements of image formed onto retina, by combining quantification of ocular media transparency and of optical aberrations. In order to evaluate its contribution in the assessment of age-related cataract, we conducted a monocentric clinical study to determine the relationships between clinical grading of lens opacity, OQAS parameters, and parameters required for cataract surgery by phacoemulsification with ultrasound (called "phacodynamics"). Clinical parameters were: best-corrected visual acuity (BCVA, expressed as Log of minimal angle resolution (logMAR)) and the lens opacity classification system III (LOCS III) as a gold standard determined by two independent observers who graded total cataract and nuclear, cortical and posterior sub capsular components. The OQAS provided an objective scatter index (OSI), a modulation transfer function (MTF, expressed in cycle per degree (cpd)) and a Strehl ratio (SR) used as an aberration marker. Patients were operated on by the same surgeon using a phacoemulsification machine that provided the cumulative dissipated energy (CDE) and total ultrasound time (US time) necessary to extract the lens. Patients with poor compliance, corneal or retinal diseases impairing OSI, or who required surgical settings variation, were excluded. Twenty-one eyes of 21 patients aged 76±8 years were analyzed. They were 11 pure nuclear, 3 pure cortical, and 7 mixed cataracts. Mean LOCS III and OSI were respectively: 4.86 ±2.03 and 6.12 ±3.07 (mean±SD). Medians (10˚-90˚percentiles) were: for BCVA 0.30 (0.10-0.70) logMAR, for MTF cutoff 9.31 (1.54-30.57) cpd, for SR 0.071 (0.042-0.146), for CDE 8.04 (5.74-23.29) and for US time 58 (39-116) seconds. LOCS III was significantly correlated (spearman r, r s) with BCVA (r s = 0.561, p = 0.008), CDE (r s = 0.457, p = 0.038) and US time (r s = 0.647, p = 0.002). The three OQAS parameters significantly correlated (all r s � 0.526, p<0.05) with BCVA, and LOCS III grading, but the strongest correlations were found with OSI for cortical components and with MTF for nuclear components: only OSI may be used objectively to assess the effect of cortical components on optical quality, and MTF cutoff-integrating scattering and aberrationsseems the best objective parameter for clinical assessment of nuclear cataracts. The three OQAS parameters were also significantly correlated (r s) with CDE, and with US time only for

Comparison Between an Intraocular Lens With Extended Depth of Focus (Tecnis Symfony ZXR00) and a New Monofocal Intraocular Lens With Enhanced Intermediate Vision (Tecnis Eyhance ICB00)

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Visual quality analysis using the Chinese Catquest-9SF scale following different spherical aberration IOL implantation

“…Different scholars have different views about the extent to which residual spherical aberration can affect postoperative visual satisfaction. Garcin et al ( 32 ) used the optical quality analysis system (OQAS) visual quality assessment system to study the postoperative visual quality with zero spherical aberration IOL. The authors reported that the best corrected visual acuity and contrast sensitivity were significantly improved after surgery.…”

A Simple Pre-Operative Nuclear Classification Score (SPONCS) for Grading Cataract Hardness in Clinical Studies

“…It showed a correlation between intra-operative phacodynamics and cataract level grading. Garcin et al recently published their correlation of Optical Quality Analysis system (OQAS Visiometrics) parameters with surgical parameters for age-related cataracts [16]. The OQAS provides objective measurements of the image formed onto the retina.…”

“…The OQAS provides objective measurements of the image formed onto the retina. It combines quantification of ocular media transparency and optical aberrations [16]. They found that OQAS parameters significantly correlated with CDE and ultrasound time, only for pure nuclear cataracts.…”