Abstract
Purpose: :
To determine if optical coherence tomography (OCT) device-type (time-domain versus spectral-domain) influences clinical grading of OCT imaging in the context of exudative age-related macular degeneration (AMD).
Methods: :
Ninety-six paired OCT scans from 49 patients with active exudative AMD were obtained on both the time-domain StratusTM OCT system and the spectral-domain CirrusTM OCT system at the same visit. Three independent graders judged each scan for the presence of intraretinal fluid (IRF) or subretinal fluid (SRF). The degree of grader consensus was evaluated and the agreement between systems was analyzed.
Results: :
CirrusTM OCT generated a higher degree of inter-grader consensus than Stratus OCT with higher intraclass correlation coefficients (ICC) for all parameters analyzed (0.78 versus 0.61, 0.88 versus 0.72, and 0.81 versus 0.74, for IRF, SRF, and decision to treat respectively). A pair-wise comparison of CirrusTM OCT to StratusTM OCT systems revealed fairly high agreement (86% and 91%, for IRF and SRF parameters respectively) with kappa values ranging from 0.62 to 0.70. Analysis of discrepant grading results between OCT systems demonstrated that CirrusTM -based gradings more frequently reported the presence of SRF and IRF compared to StratusTM-based gradings.
Conclusions: :
The choice of time-domain (StratusTM) versus spectral-domain (CirrusTM) OCT systems has a measurable impact on clinical decision making in exudative AMD, in terms of inter-grader consensus, and the rate of positive findings indicating disease activity. Clinical trials employing OCT-based clinical evaluations of exudative AMD may need to account for these inter-system differences in planning and analysis.
Keywords: age-related macular degeneration • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • retina