Comparison of the diagnostic accuracies of the Spectralis, Cirrus, and RTVue optical coherence tomography devices in glaucoma

Purpose: To compare the diagnostic accuracies of retinal nerve fiber layer (RNFL) thickness measurements obtained with the Spectralis (Heidelberg Engineering, Dossenheim, Germany), Cirrus (Carl Zeiss Meditec, Dublin, CA), and RTVue (Optovue Inc., Fremont, CA) devices for the detection of glaucoma.

Design: Diagnostic, case-control study.

Participants: A total of 233 (107 healthy, 126 glaucomatous) of 149 participants from the longitudinal Diagnostic Innovations in Glaucoma Study (DIGS) and from the African Descent and Glaucoma Evaluation Study (ADAGES).

Methods: All participants underwent RNFL thickness imaging with the Spectralis, Cirrus, and RTVue devices in the same visit. Receiver operating characteristic (ROC) curves adjusted for age and race were obtained for quadrants (superior, nasal, inferior, temporal) and global RNFL thickness for all instruments. Areas under ROC (AUC) and sensitivities at fixed specificities (80% and 95%) were calculated and compared.

Main outcome measures: Comparison of diagnostic accuracy using AUCs and sensitivities at fixed specificities of 80% and 95%.

Results: The RNFL thickness parameter with the largest AUCs was the superior quadrant for the Spectralis (0.88) and the global RNFL thickness for the Cirrus (0.88) and the RTVue (0.87). The pairwise comparison among the ROC curves showed no statistical difference for all parameters except for the nasal quadrant, which had significantly larger AUC in the Spectralis and RTVue compared with the Cirrus (P<0.03 for both comparisons). There were no significant differences in sensitivities among the best parameters from each instrument (P>0.05). The superior quadrant thickness measured with the Spectralis had sensitivity of 81.9% at a fixed specificity of 80% and 70% at a fixed specificity of 95%. The global thickness measured by the Cirrus had a sensitivity of 80.3% at a fixed specificity of 80% and 65.6% at a fixed specificity of 95%. For the RTVue, the global thickness had a sensitivity of 77.9% at a fixed specificity of 80% and 62.1% at a fixed specificity of 95%.

Conclusions: Although the spectral-domain optic coherence tomography (SD-OCT) instruments have different resolution and acquisition rates, their ability to detect glaucoma was similar.