Social History and Glaucoma Progression

Glaucoma is a multifactorial optic neuropathy characterized by structural damage of retinal ganglion cells (RGCs) and their axons that is associated with vision loss and may lead to irreversible blindness. Because glaucomatous damage is irreversible and effective treatment is available to halt further damage, glaucoma management should be optimized with precise micrometer-scale quantifications of ocular structures that improve detection of the disease and its progression. The introduction of OCT technology more than 20 years ago provided in vivo detailed visualization of the optic nerve head (ONH) and retina and enabled the quantitative evaluation of these tructures. Circumpapillary retinal nerve fiber layer (RNFL) thickness is a common OCT measurement that provides comprehensive evaluation of all RGCs in an eye as they converge into the ONH. When measured with spectral-domain OCT, the RNFL has been shown to differentiate between healthy and glaucomatous eyes. The steady evolution of OCT technology has led to imaging with better resolution, higher scanning speeds, and advanced imaging patterns that has improved the reliability of OCT measurements and allowed for detection of minute changes that can improve the sensitivity of progression detection. Assessment of glaucoma progression usually is based on event or trend analysis. Event-based progression determines when a measurement exceeds a pre-established threshold for change from baseline. Trend-based analysis quantifies the rate of a parameter's progression over time.