Choroidal Thickness Changes in Patients With Glaucoma
By Lynda Seminara
Selected By: Richard K. Parrish II, MD
American Journal of Ophthalmology, February 2018
The peripapillary choroid is of interest to researchers because its branches lend vital support to the prelaminar region of the optic nerve head, a primary site of glaucomatous optic neuropathy. Although the link between glaucoma and the choroid has been studied using optical coherence tomography, findings have been inconsistent. Mundae et al. performed spectral-domain optical coherence tomography (SD-OCT) in patients with glaucoma and healthy controls to compare rates of peripapillary choroidal thinning. Their results showed no significant difference between the study groups.
The authors’ research included participants of the multicenter African Descent and Glaucoma Evaluation Study and the Diagnostic Innovations in Glaucoma Study. The testing protocols of those studies were identical.
The healthy group (68 patients) contributed 132 eyes, and the glaucoma group (115 patients) consisted of 165 eyes. At baseline, the global mean peripapillary choroidal thickness (PCT) was significantly greater for healthy controls: 155.7 ± 64.8 μm vs. 141.7 ± 66.3 μm for patients with glaucoma (p < .001). However, when age was factored into the model, the difference was not significant (p = .38). Every eye was imaged by SD-OCT on at least 3 days. The San Diego Automated Layer Segmentation Algorithm was used to automatically segment and measure PCT from circle scans centered on the optic nerve head. Mixed-effects models were applied to calculate the rate of PCT thinning. The median follow-up time was 2.6 years.
In both study groups, PCT decreased significantly over time: –2.18 μm per year in controls and –1.88 μm per year in patients with glaucoma. Similarly, both groups had significant decreases in PCT percentage over time: –3.32% for controls and –2.85% for patients with glaucoma. However, the mean rate of PCT change over time was similar for the study groups, as was the change in PCT percentage.
Despite the observed similarities, the authors emphasized that longer follow-up is needed to determine with certainty whether monitoring the rate of PCT change has a role in glaucoma management.
The original article can be found here.