Reduced central corneal thickness and peripapillary capillary density are key screening parameters for glaucoma suspects.

Reduced central corneal thickness and peripapillary capillary density are key screening parameters for glaucoma suspects. Photo: Carolyn Majcher, OD. Click image to enlarge.

Retinal nerve fiber layer (RNFL) defects and reduced central corneal thickness (CCT) are important parameters in the assessment of glaucoma suspects. In a recent study, researchers investigated possible relationships between reduced CCT and radial peripapillary capillary (RPC) density defects in glaucoma suspects.

Peripapillary OCT-A (4.5mm) and anterior segment OCT for corneal pachymetry were performed on 92 eyes (30 females and 16 males). Cup-to-disc ratio, RNFL thickness, blood flow indices and CCT were evaluated.

A significant positive correlation was found between the total RPC and the average peripapillary RNFL thickness, as well as between the hemi-superior RPC and the superior RNFL thickness and the hemi-inferior RPC and the inferior RNFL thickness. A positive correlation was detected only between CCT and total RPC, hemi-superior RPC and hemi-inferior RPC.

“Low values of RPC, RNFL and CCT were found to be significant predictors for the presence of glaucoma after controlling the confounders of age, gender and intraocular pressure,” the authors explained. “Patients with low RPC measurement are likely to have glaucoma fivefold compared with those with high measurements. Regarding RNFL and CCT, those with low values of RNFL and CCT are 1.15fold and 1.79fold, respectively, more likely to have glaucoma compared with those with high values.”

The authors noted that OCT-A gives promising results in the detection of vascular changes in the retina and choroid. “It might play an important role in the management of glaucoma,” they explained. “Further larger studies are needed to evaluate the correlation and agreement of the presence of reduced vascular density with the other risk factors of optic disc changes and loss of ganglion cells in glaucoma.”

Lofty A, Kamal Mattout H, Mosaad Fouda S, Hemeda S. Correlation between radial peripapillary vascular density and reduced central corneal thickness in glaucoma suspect patients. BMC Ophthalmol. October 31, 2022. [Epub ahead of print].