Purchase this article with an account.
Danilo Andrade De Jesus, Luisa Sanchez Brea, João Barbosa Breda, Luis Abegão Pinto, Ingeborg Stalmans, Stefan Klein, Theo van Walsum; The superficial peripapillary vascular layer is the most informative for glaucoma diagnosis – A multi-layer study based on OCT Angiography.. Invest. Ophthalmol. Vis. Sci. 2019;60(11):PB052.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
To evaluate the ability of microvascular density obtained from OCT Angiography (OCTA) at different peripapillary layers to discriminate glaucoma from controls.
OCTA 3x3mm optic disc centred scans were retrieved from 45 healthy controls and 97 glaucoma patients with the Cirrus 5000 HD OCT (Carl Zeiss, USA). Images were analysed with an in-house algorithm that measures circumpapillar microvascular density (cpmVD) after automatically removing the Optic Nerve Head (ONH) optically hollow and large retinal vessels from the superficial layer. The resulting mask was used to retrieve the cpmVD from all six layers available (superficial, deep, avascular, whole retina, choriocapillaris, and choroid – see Fig. 1). A linear support vector machine (SVM) model with 5-fold cross validation was implemented. The area under the receiver operating characteristic curve (AUC) was computed for the cpmVD at each layer and combining multiple layers. A group comparison with the Kruskal-Wallis test followed by the Dunn test with Holm-Bonferroni correction for pairwise comparison was also performed to infer the ability of each layer to discriminate different glaucoma severity levels.
All layers showed significantly different cpmVD values between glaucoma and controls (p<0.001), with the exception of the avascular layer. The highest AUC was observed for the superficial layer (0.88±0.03; Fig. 2a). In a multi-layer analysis, the superficial and choriocapillaris layers combined showed the highest AUC (0.92±0.02; Fig. 2b). Regarding glaucoma severity, all layers, except for the avascular, showed a significant cpmVD change between levels of severity (p<0.05). However, only the superficial layer presented a significant difference between all groups in a pairwise comparison (p<0.05).
The OCTA superficial layer is the best at discriminating healthy subjects from glaucoma patients and between glaucoma severity levels. Moreover, a combination of superficial and choriocapillaris layers seems to yield an even higher accuracy.
This abstract was presented at the 2019 ARVO Imaging in the Eye Conference, held in Vancouver, Canada, April 26-27, 2019.
Automatic detection of the microvasculature area (green) for the superficial layer and use of the resulting mask in all remaining layers. The blue disc covers the ONH optically hollow area.
ROC curve for the SVM model based on each layer (a) and based on the superficial cpmVD and the combination of superficial with choriocapillaris cpmVDs (b).
This PDF is available to Subscribers Only