Contrast Sensitivity Testing in Retinal Vein Occlusion Using a Novel Stimulus

Abstract

Purpose This study evaluated a novel tool known as the motion diamond stimulus (MDS), which utilizes contrast-generated illusory motion in dynamic test regions to determine contrast sensitivity (CS). Methods Patients with treated unilateral retinal vein occlusions (RVOs) underwent three assessments: the MDS, the Pelli-Robson (PR), and the National Eye Institute's Visual Function Questionnaire (VFQ-25). The MDS assessment produced two data end points, α and β. The α value represents the overall contrast threshold level and the β value serves to quantify the adaptability of the visual contrast system. The CS parameters from the MDS and log CS PR output values were used to compare RVO eyes ( n = 20) to control eyes ( n = 20). Results The study participants had a mean composite VFQ-25 score of 89.5 ± 10.4 on the VFQ-25. A significant difference was observed between the RVO eyes and the control eyes in PR log CS scores ( P value = 0.0001) and in MDS α value ( P value = 0.01). No difference in MDS β value was found between the study groups ( P value = 0.39). Conclusions The results for the MDS assessment's α parameter corroborated the PR scores, suggesting contrast sensitivity threshold impairment in patients with RVO. No significant difference in β value was observed, suggesting that adaptability of the visual system is maintained in treated RVO eyes. Translational Relevance Currently, visual complaints cannot be entirely identified by Snellen visual acuity alone. The MDS offers potentially a more complete look at visual function, by including contrast sensitivity and may be able to quantify changes otherwise overlooked in retinal disease progression.

Endothelial Caspase-9 Promotes Glial Changes, Inflammation, and Contrast Sensitivity Decline in Retinal Vascular Injury

“…One of the effects of RVO is damage to visual function, including a significant decline in contrast sensitivity threshold (McIntosh et al, 2010; Mishra et al, 2020). Since we had previously found that EC Casp9 regulated retinal edema and retinal neuronal death in RVO (Avrutsky et al, 2020), we sought to explore whether EC Casp9 was implicated in damage to contrast sensitivity discrimination.…”

Contrast Sensitivity Testing in Age-Related Macular Degeneration Using Motion Diamond Stimulus

“…Analysis of the MDS, a novel CS testing method in development, is discussed in detail in prior studies. 18 This is the first study to test the MDS assessment in patients with AMD. CS can be helpful in early detection, monitoring, and assessing treatment response in several ocular conditions.…”

“… 9 The utility and accuracy of the gold standard Pelli-Robson CS test has been challenged, 16 and limitations of the PR include static field testing, influence of lighting, reflection, and fading on the physical chart, learning effect on repeat testing, and the necessity for patients to recognize letters. 18 Alternate CS tests such as the MDS have been developed to account for the above-mentioned limitations. The MDS tests CS in a dynamic field, is a digital rather than physical tool, has randomized directions on repeat testing, and does not require letter recognition.…”

“…The MDS test has a few inherent limitations as discussed in prior studies, such as time burden of the test and the unique β parameter. 18 The small sample size also led to a non-diverse cohort, which was dissimilar with respect to gender and age. One of the inclusion criteria was good visual acuity, which is not representative of the entire AMD population.…”

“… 17 It utilizes a stationary diamond that creates an illusion of unidirectional movement. 18 Given that the motion of the diamond is generated solely by changes in contrast, the dynamic nature of the test, and opportunity to make changes to the testing program to better identify small changes to CS, the MDS test has the potential to be a valuable tool for measures of spatial contrast, temporal contrast, and contrast gain.…”