Active Learning to Characterize the Full Contrast Sensitivity Function in Cataracts

Abstract

Background To characterize contrast sensitivity function (CSF) in cataractous and pseudophakic eyes compared to healthy control eyes using a novel quantitative CSF test with active learning algorithms. Methods This is a prospective observational study at an academic medical center. CSF was measured in eyes with visually significant cataract, at least 2+ nuclear sclerosis (NS) and visual acuity (VA) ≥ 20/50, in pseudophakic eyes and in healthy controls with no more than 1+ NS and no visual complaints, using the Manifold Contrast Vision Meter. Outcomes included Area under the Log CSF (AULCSF) and CS thresholds at 1, 1.5, 3, 6, 12, and 18 cycles per degree (cpd). A subgroup analysis as performed on cataract eyes with VA ≥ 20/25. Results A total of 167 eyes were included, 58 eyes in the cataract group, 77 controls, and 32 pseudophakic eyes with respective median AULCSF of 1.053 (0.352) vs 1.228 (0.318) vs 1.256 (0.360). In our multivariate regression model, cataract was associated with significantly reduced AULCSF (P= 0.04, β= −0.11) and contrast threshold at 6 cpd (P= 0.01, β= −0.16) compared to controls. Contrast threshold at 6 cpd was significantly reduced even in the subgroup of cataractous eyes with VA ≥ 20/25 (P=0.02, β=−0.16). Conclusion The novel qCSF test detected disproportionate significant contrast deficits at 6 cpd in cataract eyes; this remained significant even in the cataractous eyes with VA ≥ 20/25. CSF testing may enhance cataract evaluation and surgical decision-making, particularly in patients with subjective visual complaints despite good VA.

Evaluation of the SpotChecks contrast sensitivity test in healthy adults

“…The mean (SD) Pelli-Robson logCS value of 1.80 [0.09] including subjects of all ages (mean 49 [18] years) agrees with that (1.79 [0.11]) reported by Haymes et al 36 in normal subjects of similar mean age (48 [17] years) using the same scoring method. 23 The mean logCS in our younger group (<50 years, mean 34 [9] years) was 1.89 and 1.83 for SpotChecks and Pelli-Robson, respectively, which are essentially the same as those obtained previously with CamBlobs2 (a previous iteration of SpotChecks) and Pelli-Robson in young adults.…”

The Optical Coherence Tomography and Microperimetry Biomarker Evaluation in Patients with Geographic Atrophy (OMEGA) Study: Design and Baseline Characteristics – OMEGA Report 1

“…The qCSF method uses Bayesian adaptive testing to estimate the four parameters defining the participant’s CSF in a time-efficient manner [24‒26]. The test estimates a CSF curve after 25 CSF trials, generating the area under the log contrast sensitivity function curve (AULCSF), integrated from 1 to 18 cycles per degree [24‒26].…”

“…CSFs were obtained with the participant's best refraction using the qCSF method (Manifold Platform, Adaptive Sensory Technology, Lübeck, Germany). The qCSF method uses Bayesian adaptive testing to estimate the four parameters defining the participant's CSF in a time-efficient manner [24][25][26]. The test estimates a CSF curve after 25 CSF trials, generating the area under the log contrast sensitivity function curve (AULCSF), integrated from 1 to 18 cycles per degree [24][25][26].…”