Fast Measure of Visual Acuity and Contrast Sensitivity Defocus Curves with an iPad Application

Abstract

Objective:To evaluate the repeatability of the fast measurement of the visual acuity (VADC) and contrast sensitivity (CSDC) defocus curves with a new test as well as the agreement of measurements at far distance obtained with the Early Treatment Diabetic Retinopathy Study (ETDRS) chart and the ClinicCSF test for measuring Contrast Sensitivity Function (CSF).Method:Records from fifty-nine subjects implanted with Multifocal Intraocular Lenses (MIOLs) were retrieved from our database. VADC and CSDC were measured from +1.00 D to -4.00 D in 0.50 D steps. The agreement with the ETDRS and the CSF at far distance was assessed in comparison to the 0 D location of the VADC and the CSDC, respectively. The repeatability was evaluated in 34 subjects who consecutively repeated two measures.Results:Median Visual Acuity (VA) was -0.1 logMAR with the VADC at 0 D of defocus and 0 logMAR with the ETDRS (p>0.05). A total of 45.8% of eyes showed no differences between both tests and the difference was less than one line of VA in 96.6% of the eyes. The intrasubject repeatability was under one line of VA along all the defocus curve except for positive defocus levels. The CSDC showed the best agreement with the CSF for 18 cycles per degree. The CSDC was less repeatable than VADC. Mean time spent on completing the VADC and CSDC was 7.81 and 7.98 minutes, respectively.Conclusion:The VADC showed good agreement with the ETDRS and good repeatability despite the short testing time. In contrast, poorer repeatability was found for CSDC. Our method would facilitate the inclusion of VADC in clinical practice as it is a fast test, being also the first one including the measure of CSDC.

Long-Term Efficacy, Visual Performance and Patient Reported Outcomes with a Trifocal Intraocular Lens: A Six-Year Follow-up

“…Particularly, CSDC has not been reported for short periods of time with the 839MP IOL. Comparing the performance for 0 D defocus location, the point that usually shows less difference in MTF between trifocal IOLs [ 27 ], the level slightly above 0.8 logCS found for a background brightness of 85 cd/m 2 in the current series was very close to the mean of 0.83 logCS obtained with several MIOLs for a background brightness of 250 cd/m 2 [ 28 ]. This suggest that not only visual acuity remains stable 6 years after surgery, but also probably contrast sensitivity.…”

The Influence of Angle Alpha, Angle Kappa, and Optical Aberrations on Visual Outcomes after the Implantation of a High-Addition Trifocal IOL

“…Monocular uncorrected and corrected visual acuity and contrast sensitivity defocus curves (VADC and CSDC, respectively) were measured and plotted one and three months following IOL implantation, using the Multifocal Lens Analyzer 3.0 application designed for iPad devices (Qvision, Madrid, Spain; defocuscurve.com (accessed on 2 January 2022)) [27]. During the measurements and analysis, the recommendations and protocols provided by the developers were applied [28]. The range of defocus was measured between +1.00 and −4.00 D with 0.5 D increments in each case.…”

Pupil dependence assessment with multifocal intraocular lenses through visual acuity and contrast sensitivity defocus curves

“…At 1 month after surgery, corrected and uncorrected VAs were obtained at three distances (far, 67and 40 cm) in the right eye with an iPad ETDRS chart (VisionC; test-eye.com; Spain). Fast defocus curves 12 were also measured for high contrast VA and CS with two optotype sizes corresponding to 0.3 logMAR (CSDC3) and 0.7 logMAR (CSDC7) with the Multifocal Lens Analyzer (MLA 1.0.8; defocuscurve.com; Spain) for iPad at 2 m, with a +0.50 D lens added for correcting the vergence distance. Defocus lenses from +1.00 D to −4.00 D in steps of 0.50 D were selected for measuring defocus curves with the best distance spectacle refraction.…”