Predicting individual contrast sensitivity functions from acuity and letter contrast sensitivity measurements

Abstract

Contrast sensitivity (CS) is widely used as a measure of visual function in both basic research and clinical evaluation. There is conflicting evidence on the extent to which measuring the full contrast sensitivity function (CSF) offers more functionally relevant information than a single measurement from an optotype CS test, such as the Pelli–Robson chart. Here we examine the relationship between functional CSF parameters and other measures of visual function, and establish a framework for predicting individual CSFs with effectively a zero-parameter model that shifts a standard-shaped template CSF horizontally and vertically according to independent measurements of high contrast acuity and letter CS, respectively. This method was evaluated for three different CSF tests: a chart test (CSV-1000), a computerized sine-wave test (M&S Sine Test), and a recently developed adaptive test (quick CSF). Subjects were 43 individuals with healthy vision or impairment too mild to be considered low vision (acuity range of −0.3 to 0.34 logMAR). While each test demands a slightly different normative template, results show that individual subject CSFs can be predicted with roughly the same precision as test–retest repeatability, confirming that individuals predominantly differ in terms of peak CS and peak spatial frequency. In fact, these parameters were sufficiently related to empirical measurements of acuity and letter CS to permit accurate estimation of the entire CSF of any individual with a deterministic model (zero free parameters). These results demonstrate that in many cases, measuring the full CSF may provide little additional information beyond letter acuity and contrast sensitivity.

Visual Function and Macular Carotenoid Changes in Eyes with Retinal Drusen—An Open Label Randomized Controlled Trial to Compare a Micronized Lipid-Based Carotenoid Liquid Supplementation and AREDS-2 Formula

“…The VectorVision CSV-1000E device (Greenville, OH, USA) was used to measure contrast sensitivity function (CSF). Measurements were obtained via standardized patient procedures described in prior publications [33][34][35]. Briefly, contrast sensitivity is measured with participants using their best correction and viewing the chart at 2.5 m distance.…”

“…Briefly, contrast sensitivity is measured with participants using their best correction and viewing the chart at 2.5 m distance. The chart is rear illuminated (mean luminance 85 cd/m 2 ) and presents a series of achromatic sine-wave targets of varying spatial frequency, incorporating 3, 6, 12, and 18 cycles per degree (CPD) in four separate rows [33][34][35]. Across each row, vertical target pairs with eight different contrast levels, respectively, are present and scores are recorded in log contrast sensitivity [33][34][35].…”

“…The participants were presented a suprathreshold example of a test pattern, and subsequently instructed to identify the test pattern between two targets presented on different rows [33][34][35]. This was continued to the next level of contrast threshold and spatial frequency.…”

Functional reallocation of sensory processing resources caused by long-term neural adaptation to altered optics

“…We also estimated the high-SF cutoff ( ) from qCSF fits – a measure of VA. The qCSF method has been used to characterize CSF in both neurotypical and diverse clinical populations ( Hou et al, 2010 ; Hou et al, 2016 ; Lesmes et al, 2010 ; Thurman et al, 2016 ; Yan et al, 2017 ).…”

<p>The Effects of Blue Light–Filtering Intraocular Lenses on the Protection and Function of the Visual System</p>

“…Glare disability is assessed using intense light sources often based on simulated sunlight in a laboratory or clinical setting. For instance, contrast sensitivity can be measured under glare conditions with clinical devices (eg, the CVS1000HGT chart-based test [VectorVision, Greenville, OH] that can produce reliable measurements of the contrast sensitivity function) 30,31. Alternatively, contrast sensitivity can be measured using a 1-degree grating target surrounded by an annular source of broadband white light,32 where the intensity of the annulus is increased until the glare disability threshold is reached (in this case, glare disability threshold is defined as the magnitude of glare that causes the central grating to be occluded owing to light scattering in the media of the eye).…”