Abstract
Purpose: :
To report the frequency and severity of retinal thickness measurement errors in a Fourier domain optical coherence tomography (OCT) device, Cirrus OCT, and to describe morphologic and disease diagnosis characteristics that predict these errors.
Methods: :
Data from 209 consecutive patients (209 eyes) undergoing Cirrus OCT imaging with the Macular Cube protocol were collected. For each eye, the position of the automated retinal boundary lines used by the Cirrus OCT software for thickness calculations was assessed using a 6-point categorical scale, and an average error score was generated. The presence of thickness errors was correlated with various parameters including: retinal morphologic features, disease diagnosis, foveal central subfield thickness, and OCT signal strength.
Results: :
Errors of retinal boundary detection and thickness measurement were observed in 57.5% of eyes but were severe in only 9.6% of eyes. The identification of subretinal fluid, subretinal tissue, pigment epithelium detachment, or a diagnosis of choroidal neovascularization was associated with more severe errors. Retinal cysts or a diagnosis of retinal vascular disease (e.g. diabetic macular edema) were less likely to be associated with significant error.
Conclusions: :
Retinal thickness measurement errors appear to occur less frequently with Fourier domain OCT (Cirrus OCT), but segmentation errors remain a concern, particularly for the accurate assessment of eyes with structurally complex retinal disease. With the recent release of multiple FDOCT systems, assessment of segmentation error may be an important factor in determining the relative clinical applicability of these systems.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • retina • imaging/image analysis: clinical