Normal tension glaucoma: A dynamic optical coherence tomography angiography study

January 24, 2023 | Ophthalmology | K. U. Leuven

Alexander Heintz, Claire van der Pluijm, Dries De Witte, Geert Molenberghs, Ingeborg Stalmans, Jan Van Eijgen, João Barbosa-Breda, Margaux Delporte

Purpose: Vascular dysregulation seems to play a role in the pathogenesis of glaucoma, in particular normal tension glaucoma (NTG). The development of optical coherence tomography angiography (OCTA) enabled the measurement of the retinal microvasculature non-invasively and with high repeatability. Nonetheless, only a few studies transformed OCTA into a dynamic examination employing a sympathomimetic stimulus. The goal of this study was to use this dynamic OCTA exam (1) to differentiate healthy individuals from glaucoma patients and (2) to distinguish glaucoma subcategories, NTG and high-tension primary open angle glaucoma (POAG). Methods: Retinal vessel density (VD) in NTG patients (n = 16), POAG patients (n = 12), and healthy controls (n = 14) was compared before and during a hand grip test with a hydraulic dynamometer. Results: At baseline, mean peripapillary VD was lower in POAG and NTG (42.6 and 48.5%) compared to healthy controls (58.1%; p < 0.001) and higher in NTG com...

Automatic Segmentation of the Optic Nerve Head Region in Optical Coherence Tomography

April 29, 2022 | Ophthalmology | Erasmus University, K. U. Leuven, University of Coimbra

Danilo Andrade De Jesus, Ingeborg Stalmans, Jan Van Eijgen, João Barbosa-Breda, Luisa Sánchez Brea, Pedro G. Vaz, Rita Marques, Stefan Klein, Theo van Walsum

The optic nerve head (ONH) represents the intraocular section of the optic nerve, which is prone to damage by intraocular pressure (IOP). The advent of optical coherence tomography (OCT) has enabled the evaluation of novel ONH parameters, namely the depth and curvature of the lamina cribrosa (LC). Together with the Bruch's membrane minimum-rim-width (BMO-MRW), these seem to be promising ONH parameters for diagnosis and monitoring of retinal diseases such as glaucoma. Nonetheless, these OCT derived biomarkers are mostly extracted through manual segmentation, which is time-consuming and prone to bias, thus limiting their usability in clinical practice. The automatic segmentation of ONH in OCT scans could further improve the current clinical management of glaucoma and other diseases. This review summarizes the current state-of-the-art in automatic segmentation of the ONH in OCT. PubMed and Scopus were used to perform a systematic review. Additional works from other databases (IEEE, Goo...

Optical Coherence Tomography Imaging of the Lamina Cribrosa: Structural Biomarkers in Nonglaucomatous Diseases

February 23, 2021 | Ophthalmology

Alice Paulo, Danilo Andrade De Jesus, Ingeborg Stalmans, Jan Van Eijgen, João Barbosa-Breda, João Cardoso, Luisa Sánchez Brea, Pedro G. Vaz, Stefan Klein, Theo van Walsum

The lamina cribrosa (LC) is an active structure that responds to the strain by changing its morphology. Abnormal changes in LC morphology are usually associated with, and indicative of, certain pathologies such as glaucoma, intraocular hypertension, and myopia. Recent developments in optical coherence tomography (OCT) have enabled detailed in vivo studies about the architectural characteristics of the LC. Structural characteristics of the LC have been widely explored in glaucoma management. However, information about which LC biomarkers could be useful for the diagnosis, and follow-up, of other diseases besides glaucoma is scarce. Hence, this literature review aims to summarize the role of the LC in nonophthalmic and ophthalmic diseases other than glaucoma. PubMed was used to perform a systematic review on the LC features that can be extracted from OCT images. All imaging features are presented and discussed in terms of their importance and applicability in clinical practice. A tota...

Combination of snapshot hyperspectral retinal imaging and optical coherence tomography to identify Alzheimer’s disease patients

November 11, 2020 | Ophthalmology | K. U. Leuven

Arnout Standaert, Danilo Andrade De Jesus, Gordana Sunaric-Mégevand, Ingeborg Stalmans, Jan Theunis, Jan Van Eijgen, Karel Van Keer, Lies De Groef, Lieve Moons, Mathieu Vandenbulcke, Murali Jayapala, Patrick De Boever, Rik Vandenberghe, Rose Bruffaerts, Sophie Lemmens, Toon Van Craenendonck, Wouter Charle

The eye offers potential for the diagnosis of Alzheimer’s disease (AD) with retinal imaging techniques being explored to quantify amyloid accumulation and aspects of neurodegeneration. To assess these changes, this proof-of-concept study combined hyperspectral imaging and optical coherence tomography to build a classification model to differentiate between AD patients and controls. ( Read Full Article )