Abstract
Purpose:
To investigate the interobserver and intraobserver reproducibility of peripapillary choroidal thickness measurements performed by enhanced depth imaging spectral-domain optical coherence tomography (EDI-OCT) in a population with and without glaucoma.
Methods:
We prospectively enrolled glaucomatous patients (glaucomatous optic neuropathy and reproducible visual field defect) and healthy individuals from August 2012 to October 2012. Those with significant media opacity or any ocular disease (besides glaucoma) were excluded. All participants underwent EDI-OCT (SD-OCT; Spectralis®, Wavelength: 870nm; Heidelberg Engineering Co., Heidelberg, Germany). The peripapillary choroid was measured 500µm distant from the inferior margin of the Bruch’s membrane opening. To examine the inter-observer reproducibility, two independent examiners assessed all images. To examine the intraobserver reproducibility, each examiner evaluated each set of images twice. The intra-session within-subject standard deviation (Sw), the coefficient of variation (COV; 100%×Sw/overall mean) and the intra-class correlation coefficient (ICC; set for absolute agreement) were calculated.
Results:
A total of 10 eyes of 10 patients were included. Mean peripapillary choroidal thickness by graders 1 and 2 were 145.8±41.2 μm and 140.1±30.7 μm, respectively, with a mean difference of 5.7 μm (P=0.73; 95% confidence interval of the difference: -39.9 - 28.4). For the assessment of the intra-observer reproducibility for graders 1 and 2, the mean Sws were 7.3 and 6.3 μm, the mean COVs were 5.6 and 4.8% and the ICCs were 0.96 (95% CI, 0.85 - 0.99) and 0.95 (95% CI, 0.80 - 0.98), respectively.
Conclusions:
Based on manual measurement performed by experienced examiners, measurements of the peripapillary choroidal thickness by EDI OCT showed a high reproducibility among the observers.
Keywords: 465 clinical (human) or epidemiologic studies: systems/equipment/techniques