Glaucoma Diagnosis and Monitoring Using Advanced Imaging Technologies

Abstract

Advanced ocular imaging technologies facilitate objective and reproducible quantification of change in glaucoma but at the same time, impose new challenges on scientists and clinicians for separating true structural change from imaging noise. This review examines time-domain and spectral-domain optical coherence tomography, confocal scanning laser ophthalmoscopy and scanning laser polarimetry technologies and discusses the diagnostic accuracy and the ability of each technique for evaluation of glaucomatous progression. A broad review of the current literature reveals that objective assessment of retinal nerve fiber layer, ganglion cell complex and optic nerve head topography may improve glaucoma monitoring when used as a complementary tool in conjunction with the clinical judgment of an expert.

Baseline structural characteristics of the optic nerve head and retinal nerve fiber layer are associated with progressive visual field loss in patients with open-angle glaucoma

“…In addition to cup/disc ratios, the evaluation of the RNFL thickness by OCT and HRT-III can be useful in the clinical setting, as certain RNFL characteristics were associated with a shorter time to functional disease progression over the course of five years. Similar to our findings, Sehi et al showed that progressive RNFL loss was associated with functional glaucoma progression [13], while Lalezary et al showed that thinner baseline RNFL, as measured by OCT, was an independent predictor of functional glaucomatous changes [14]. Our data also show that baseline optic disc cup shape, based on measures of the topography including cup size, cup depth, neuroretinal rim slope, and RNFL curvature, appears to be a significant predictor of glaucoma progression.…”

“…Similar to our findings, Sehi et al . showed that progressive RNFL loss was associated with functional glaucoma progression [ 13 ], while Lalezary et al . showed that thinner baseline RNFL, as measured by OCT, was an independent predictor of functional glaucomatous changes [ 14 ].…”

“…Because of these findings, others have investigated the utility of various imaging modalities on determining structural differences between normal healthy eyes and those suffering from glaucoma [ 10 – 12 ]. These studies have found that baseline structural measurements, including RNFL thinning and cup shape, are associated with functional glaucomatous progression [ 13 – 16 ]. However, the results from these studies are varied, and the exact relationship between baseline structural characteristics of the ONH and RNFL and functional disease progression has not been fully delineated.…”

Investigation of lateral geniculate nucleus volume and diffusion tensor imaging in patients with normal tension glaucoma using 7 tesla magnetic resonance imaging

“…The neuroretinal rim area is measured in 6 sectors (temporal superior, nasal superior, nasal, nasal inferior, temporal inferior and temporal) as well as globally. RNFL thickness is measured as the difference between the inner margin of the ILM (internal limiting membrane) and the outer margin of the RNFL and the obtained values are automatically compared to a normative database [ 17 , 18 ].…”

Can Automated Imaging for Optic Disc and Retinal Nerve Fiber Layer Analysis Aid Glaucoma Detection?

“… 6 , 7 The RNFL can be assessed using either scanning laser polarimetry, currently available as the GDx-PRO (Glaucoma Diagnostics [GDx] Carl Zeiss Meditec, Dublin, CA) 8 or spectral-domain optical coherence tomography (OCT), with several commercial devices available. 9 These imaging tests are user friendly and provide automated quantitative classifications. 10 …”