2020–2021 BCSC Basic and Clinical Science Course™
Chapter 5: Clinical Evaluation and Imaging of the Posterior Segment: Optic Nerve, Retinal Nerve Fiber Layer, and Macula in Glaucoma
Glaucomatous damage tends to preferentially affect the inferior and superior poles of the optic disc, especially in the early stages of the disease.
Funduscopic determination of the cup–disc ratio is an insufficient and generally inaccurate way of documenting the amount of optic nerve damage in glaucoma. It is preferable to obtain objective documentation of the appearance of the optic disc by photographs or imaging whenever possible.
Optical coherence tomography (OCT) is the most commonly used imaging technique. OCT provides quantitative measurements of the peripapillary retinal nerve fiber layer thickness, optic nerve head topography, and macular thickness, which can help discriminate glaucomatous eyes from healthy eyes.
Glaucomatous damage frequently affects the macular region, leading to central visual field losses that can go undetected with conventional perimetry. This damage may be detectable by OCT imaging of the macula.
It is important to consider the possible effects of aging on longitudinal changes of OCT parameters over time.
Excerpted from BCSC 2020-2021 series: Section 10 - Glaucoma. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.