Relationships of orientation discrimination threshold and visual acuity with macular lesions in age-related macular degeneration

Abstract

PurposeTo measure visual acuity and metamorphopsia in patients with age-related macular degeneration (AMD) and to explore their relationship with macular lesions.MethodsIn this cross-sectional study, a total of 32 normal subjects (32 eyes) and 35 AMD patients (35 eyes) were recruited. They were categorized into 4 groups: normal, dry AMD, non-active wet AMD, and active wet AMD. Best-corrected visual acuity (BCVA) was measured using the Early Treatment Diabetic Retinopathy Study protocol. Metamorphopsia was quantified with the orientation discrimination threshold (ODT). Macular lesions, including drusen, sub-retinal fluid (SRF), intra-retinal fluid (IRF), pigmented epithelium detachment (PED), and scarring, were identified with spectral-domain optical coherence tomography (SD-OCT). A linear regression model was established to identify the relationships between the functional and structural changes.ResultsBCVA progressively worsened across the normal, dry AMD, non-active wet AMD, and active wet AMD groups (P < 0.001), and ODT increased across the groups (P < 0.001). The correlation between BCVA and ODT varied among the groups. The partial correlation between BCVA and ODT was −0.61 (P < 0.001). Linear regression showed that ODT significantly depended on IRF (β = 0.61, P < 0.001), SRF (β = 0.34, P = 0.003), and scarring (β = 0.26, P = 0.050), while BCVA significantly depended only on scarring (β = −0.52, P < 0.001), and IRF (β = −0.36, P = 0.016).ConclusionsFrom dry AMD to active wet AMD, BCVA gradually worsened while ODT increased. The correlation between BCVA and ODT varied among these groups, indicating that AMD lesions affect them differently. ODT and BCVA should be used concurrently for better monitoring of the disease.

Assessing the reliability of web-based measurements of visual function

“…For example, the intraclass correlation coefficient (ICC) quantifies the reliability between measures and can account for one-to-one differences (Koo & Li, 2016), and Bland-Altman analyses assess the level of agreement between measures and can quantify and control for any systematic differences (Bland & Altman, 1986, 1999. Demonstrating agreement between web-and lab-based measurements in visual tasks is highly important for any potential clinical applications of web-based testing, especially where individual performance is associated with pathological structural changes (Bedell et al, 2009;Fu et al, 2017;Ogata et al, 2019;Wang et al, 2013).…”

“…The ratio scale (right y-axis) allows visualisation of the magnitude of difference between lab and web thresholds experimental conditions in measures of early visual cortical function, particularly for tasks which are robust to variability in screen resolution and luminance scaling, such as orientation-discrimination (Shepherd, 2020), visual crowding (Q. Li et al, 2020), global orientation-identification (Bedell et al, 2009;Fu et al, 2017), global motion discrimination (Shepherd, 2020), and shape discrimination (Wang et al, 2002;Wang et al, 2013). Nonetheless, caution should be exercised when generalising results to other web-based experimental tasks.…”

“…Common barriers that can prevent patients from receiving treatment include cost, independent travel, and time commitments (Hartnett, 2005;Javitt & Aiello, 1996;Varano et al, 2015). Webbased methods would be especially useful in cases where performance on a psychophysical task is tracked over time, such as assessments of disease progression or treatment outcomes (Fu et al, 2017;Ogata et al, 2019;Wang et al, 2013), or monitoring of cyclical disorders such as migraine (Shepherd, 2020). However, agreement between web-and lab-based measurements should also be demonstrated in clinical populations before developing web-based tasks for clinical settings.…”

Time Course of Perceived Visual Distortion and Axial Length Growth in Myopic Children Undergoing Orthokeratology

“…The fixation ring then reappeared for 50 ms; the second stimulus pattern was presented 1 s later for 50 ms and was followed by a 200 ms blank interval. The duration of each pattern was set at 50 ms to minimize the effect of scanning eye movements ( Fu et al, 2017 ; Chen et al, 2018 ). All ODT tests were performed with full optical correction to remove the lower order aberrations, including defocus and astigmatism.…”

The role of future treatments in the management of neovascular age-related macular degeneration in Europe

“…29,36 The presence of IRF at initial diagnosis is associated with worse initial VA as well as lower long-term functional recovery. 34,37,38 Similarly, recurrence of IRF have a poorer functional prognosis and lead to long-term vision loss. 39 Subretinal fluid (SRF).…”