Abstract
Purpose :
To investigate the rate of average retinal nerve fiber layer (RNFL) thickness change and progressive visual field loss in young myopic normal-tension glaucoma (NTG) patients.
Methods :
We included 35 eyes of 35 myopic NTG patients between 19 to 39 years of age with spherical equivalent of less than -1.00 diopters. They were treated with topical intraocular pressure lowering medication and followed up for more than 5 years. All patients underwent stereo optic disc photography, red-free RNFL photography, spectral-domain optical coherence tomography (SD-OCT), and standard automated perimetry (SAP). The structural and functional progression rates were evaluated by using the average RNFL thickness on SD-OCT (um/year) and the SAP mean deviation (dB/year), respectively, by linear regression analysis. Associated factors for progression were evaluated by using univariate and multivariate regression analyses.
Results :
The mean age of included patients was 35.7 ± 4.7 years and their average refractive errors were -5.90 ± 3.85 diopters. During the average follow-up period of 5.0 ± 1.2 years, the mean rate of change in visual field MD was -0.04 ± 0.51 dB/year (P = 0.622) and average RNFL thickness change was -0.54 ± 0.99 um/year (P = 0.003). Patients with thinner baseline average RNFL thickness (P = 0.036) and shorter axial length (P = 0.017) showed significantly faster structural progression rate in average RNFL thickness. Patients with more advanced stage of glaucoma with lower baseline MD (P = 0.010) and higher pattern standard deviation (P = 0.014) values showed significantly faster rate of functional progression.
Conclusions :
In young NTG patients during the average follow-up period of 5 years, significant structural progression was found in contrast with slow and insignificant functional progression. Those with lower baseline RNFL thickness, shorter axial length, lower baseline MD, and higher baseline pattern standard deviation should be carefully monitored for the possibility of progressive glaucomatous change.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.