Optical coherence tomography measured retinal nerve fiber layer thickness values compensated with a multivariate model correspond with progressive optic disc change as documented in a longitudinal follow up with confocal scanning laser tomography in glaucoma suspects

Abstract

Purpose : To determine whether glaucoma suspect patients with our without prior progressive optic disc (OD) change are behaving different in the retinal nerve fiber layer (RNFL) measurement with optical coherence tomography (OCT), and how application of a model compensating for intersubject variability impacts this difference.

Methods : A sample of 25 glaucoma suspects characterized by suspect appearance of the OD but with normal visual field, 14 with and 11 without prior progressive OD change in a series of at least 4 confocal scanning laser tomography (CSLT) (HRT®III) measurements underwent OCT (Cirrus®) measurements of the circumpapillary RNFL. Change during the CSLT follow-up was determined with strict criteria of the Topographic Change Analysis¹. For 12 clock hour sectors of the RNFL, age correction was applied as well as correction by a multivariate model, which accounted for differences in refraction, age, retinal vessel density, OD parameters and macular parameters.²

Results : The median (interquartile range) total CSLT follow-up was 103.91 (39.0 –185.0) months. For the multivariate model, in t-test the 6 o clock sector showed significant thinner RNFL thickness values in glaucoma suspects with progressive optic disc change compared to patients with stable optic disc parameters (p= 0.018). The same could be found at 11 o clock with borderline significance (p=0.053). For uncorrected and age-corrected RNFL values, progredient glaucoma suspects did not show such differences.

Conclusions : There was a difference between stable and progressive glaucoma suspects in the peripapillary RNFL thickness temporal superior and inferior, but only after correction with our multivariate model. Reducing interindividual variability through using a multivariate compensation method might improve detection of preperimetric glaucoma among glaucoma suspects.

1 Bowd C, et al. Performance of confocal scanning laser tomograph Topographic Change Analysis (TCA) for assessing glaucomatous progression. Invest Ophthalmol Vis Sci 2009;50:691–701
2 Pereira I, et al. Multivariate Model of the Intersubject Variability of the Retinal Nerve Fiber Layer Thickness in Healthy Subjects. Invest Ophthalmol Vis Sci. 2015 Aug;56:5290-8

This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.