Abstract
Purpose: :
To determine the structure-function correlation in preperimetric glaucoma(PPG) using frequency-doubling technology (FDT), speckle-noise-reduced spectral domain optical coherence tomography (enhanced SD-OCT), single-scan SD-OCT (RTVue-100), and Heidelberg Retinal Tomograph II (HRT II).
Methods: :
This study included 26 eyes of 23 patients with PPG and 20 eyes of 15 normal subjects. All subjects underwent standard automated perimetry 24-2, FDT 24-2, enhanced SD-OCT(Spectralis HRA+OCT), RTVue-100, and HRT II. Circumpapillary retinal nerve fiber layer (cpRNFL) thickness was measured on enhanced SD-OCT. Ganglion cell complex (GCC) thickness was measured on RTVue-100. Optic nerve head (ONH) topographical parameters [rim area/rim volume] were measured on HRT II. Pearson correlation coefficient was calculated among the measurements. The ability to discriminate PPG from normal eyes was assessed by the area under the receiver operating characteristic curves (AUROC).
Results: :
In eyes with PPG, FDT-mean deviation(MD) significantly correlated only with rim area (r = 450, P = 0.021), but not with cpRNFL and GCC thickness (P = 0.162, and P = 0.548, respectively). The cpRNFL thickness significantly correlated with rim area and GCC thickness (r = 466, P = 0.017, and r = 791, P < 0.01, respectively). There was no significant correlation between rim area and GCC thickness(P = 0.118). The AUROC for FDT-MD, cpRNFL, GCC, and rim area were 0.762, 0.884, 0.815, and 0.599, respectively. The Venn diagram of abnormalities in each structure showed that the addition of cpRNFL or GCC to FDT increased the diagnostic power(sensitivity + specificity) from 1.59(0.69 + 0.90) to 1.74(0.84 + 0.90) and 1.76(0.96 + 0.80), while the addition of HRT II decreased from 1.59(0.69 + 0.90) to 1.30(0.80 + 0.50).
Conclusions: :
FDT-MD did not correlate with structural parameters except for rim area in PPG. The combination of FDT and cpRNFL or GCC resulted in improved diagnostic power for PPG detection.
Keywords: visual fields • optic nerve • ganglion cells