Abstract
Purpose: :
To evaluate the reproducibility of Ganglion Cell Complex(GCC)measurements with Fourier-Domain OCT and to determine the diagnostic accuracy of GCC analysis in distinguish between healthy and glaucomatous eyes.
Methods: :
60 eyes from 60 normal subjects and 63 eyes from 63 glaucoma patients attending our institute, were enrolled. All patients underwent a full eye examination, standard achromatic perimetry (SAP)and were imaged with Fourier-Domain OCT. Ganglion Cell Complex thickness was measured using the GCC scan protocol three times on the same days. SITA 24-2 visual field loss (PSD and MD p<5% and Glaucoma Hemifield Test outside normal limits) on two consecutive visual fields was used as reference test to define glaucoma patients.Reproducibility was assessed by Intraclasss Correlation Coefficient(ICC), Coefficient of Variation(COV) and test-retest variability. Area under receiving operating characteristics(AROC) curve were calculated for each GCC scan index, as measure of diagnostic accuracy. Sensitivity at 90% fixed specificity was also evaluated.
Results: :
The ICC ranged from 0.977(FLV) to 0.991(GLV). Average GCC thickness, Superior GGC thickness and Inferior GCC thickness showed a COV of 1.8%, 2.0% and 1.9% respectively. Test retest variability ranged from 4.4 to 4.9 µm.The area under the ROC curve for FLV%, GLV%, Average GCC thickness, Superior GGC thickness and Inferior GCC thickness were 0.874, 0.850, 0.855, 0.844, 0.858 respectively. At a fixed specificity of 90%, FLV%(a pattern parameter) had the highest sensitivity (72.2%, cut-off point: 1.666)
Conclusions: :
Macular Ganglion Cell Complex analysis provided by Fourier Domain OCT showed a good reproducibility for each of his index and a good diagnostic performance in the diagnosis of glaucoma. FLV% pattern parameter was the best discriminating parameter.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • imaging/image analysis: clinical • macula/fovea