Abstract
Purpose :
Diagnosis of glaucoma in highly myopic eyes is often limited by structural changes related to myopia, such as optic disc tilt and large parapapillary atrophy. We performed a retrospective, observational clinical study to determine the usefulness of optical coherence tomography (OCT) angiography (OCTA) in detecting glaucomatous retinal nerve fiber layer (RNFL) defect in highly myopic eyes.
Methods :
A total of 60 eyes (30 eyes with glaucoma and 30 control eyes) with high myopia (axial length > 27 mm), who showed segmentation failure in the spectral-domain OCT circumpapillary RNFL thickness measurement underwent swept-source OCTA centered on the optic nerve head. Peripapillary retinal vasculature was examined in the en-face OCTA images, and topographic correlation between the hemispheric location of the decreased retinal vasculature and the hemifield visual field defect was evaluated in the glaucoma group.
Results :
En-face OCTA identified a decreased retinal microvasculature simulating localized wedge-shaped RNFL defect in 25 of the 30 glaucomatous eyes at the location corresponded to the hemifield visual field defect. None of the control eyes showed such decreased retinal microvasculature in the OCTA images. The RNFL defect was not clearly visible by red-free fundus photography because of the low reflectance of RNFL in either group.
Conclusions :
OCTA was useful to detect glaucomatous RNFL defect in highly myopic eyes. OCTA could serve as a useful adjunct to evaluate glaucomatous damage in high myopia, where the evaluation of glaucoma is frequently confounded using other tests.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.