Abstract
Purpose :
To categorize the structural progression of glaucoma, as detected by optical coherence tomography guided progression analysis (OCT GPA), for the peripapillary retinal nerve fiber layer (RNFL) and macular ganglion cell-inner plexiform layer (GCIPL) using hierarchical cluster analysis.
Methods :
A total of 164 eyes were enrolled. Peripapillary RNFL thickness and macular GCIPL thickness were assessed using Cirrus HD-OCT, and progressive GCIPL and RNFL thinning were detected using event GPA OCT. Structural progression was classified using hierarchical cluster analysis. Visual field progression was defined as linear regression analysis of mean deviation and guidelines for early glaucoma guidance. Clinical parameters of each cluster were compared.
Results :
There were three groups: stable, peripapillary RNFL thinning progression without macular GCIPL involvement, and both peripapillary RNFL and macular GCIPL thinning progression groups. The both peripapillary RNFL and macular GCIPL thinning progression group showed relatively more reduction of peripapillary RNFL thickness in the inferotemporal area and more VF progression. Superotemporal peripapillary RNFL thinning at the 10 and 7 o’ clock areas was related to superior and inferior GCIPL progression, respectively.
The visual field progression of the perinasal scotoma region was the most prominent in the RNFL only progression group.
Conclusions :
There are differences between the rate of change and the location of RNFL thinning progression among the three groups categorized based on the structural progression of glaucoma. The topographic relationship between the peripapillary RNFL thinning progression and macular GCIPL thinning progression appears to be different between the superior and inferior macula. In particular, superior macular GCIPL thinning progression is less associated with the progression of peripapillary RNFL thinning. The location of the VF progression is also different among the three clusters. Therefore, macular GCIPL analysis alone can overlook the change in the outer macula that may affect the peripheral VF.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.