Publications by authors named "A M McKendrick"
Exploring the Phenotype and Possible Mechanisms of Palinopsia in Visual Snow Syndrome.
Invest Ophthalmol Vis Sci
October 2024
Purpose: Palinopsia (persistent afterimages and/or trailing) is a common but poorly understood symptom of the neurological condition visual snow syndrome. This study aimed to collect a phenotypical description of palinopsia in visual snow syndrome and probe for abnormalities in temporal visual processing, hypothesizing that palinopsia could arise from increased visibility of normal afterimage signals or prolonged visible persistence.
Methods: Thirty controls and 31 participants with visual snow syndrome (18 with migraine) took part.
Article Synopsis
- * It involved 54 participants with diabetes and 48 controls undergoing various tests, revealing that those with diabetes had poorer contrast sensitivity and slowed response times in visual tasks.
- * Findings indicated that while diabetics exhibited less circular foveal avascular zones, there were no significant differences in foveal vessel density, suggesting that functional impairments may not directly correlate with vascular changes in the retina.
Eccentricity Dependency of Retinal Electrophysiological Deficits in People With Episodic Migraine.
Invest Ophthalmol Vis Sci
September 2024
Purpose: During the non-attack period, people with migraine may show retinal dysfunction. This study builds on previous work by exploring the possibility of foveal and non-foveal visual field and electroretinographic deficits and determining the overlap in eccentricity of such localized visual deficits in people with migraine.
Methods: Visual fields and multifocal electroretinography (mf-ERG) were tested in 27 people with migraine (aged 19-45 years) and 18 non-headache controls (aged 20-46 years).
Purpose: Visual snow is the hallmark of the neurological condition visual snow syndrome (VSS) but the characteristics of the visual snow percept remain poorly defined. This study aimed to quantify its appearance, interobserver variability, and effect on measured visual performance and self-reported visual quality.
Methods: Twenty-three participants with VSS estimated their visual snow dot size, separation, luminance, and flicker rate by matching to a simulation.