The Impact of Utilizing Different Optical Coherence Tomography Devices for Clinical Purposes and in Multiple Sclerosis Trials

Abstract

Optical coherence tomography (OCT) derived retinal measures, particularly peri-papillary retinal nerve fiber layer (RNFL) thickness, have been proposed as outcome measures in remyelinating and neuroprotective trials in multiple sclerosis (MS). With increasing utilization of multiple centers to improve power, elucidation of the impact of different OCT technologies is crucial to the design and interpretation of such studies. In this study, we assessed relation and agreement between RNFL thickness and total macular volume (in MS and healthy controls) derived from three commonly used OCT devices: Stratus time-domain OCT, and Cirrus HD-OCT and Spectralis, two spectral-domain (SD) OCT devices. OCT was performed on both Cirrus HD-OCT and Stratus in 229 participants and on both Cirrus HD-OCT and Spectralis in a separate cohort of 102 participants. Pearson correlation and Bland-Altman analyses were used to assess correlation and agreement between devices. All OCT retinal measures correlated highly between devices. The mean RNFL thickness was 7.4 µm lower on Cirrus HD-OCT than Stratus, indicating overall poor agreement for this measurement between these machines. Further, the limits of agreement (LOA) between Cirrus HD-OCT and Stratus were wide (−4.1 to 18.9 µm), indicating poor agreement at an individual subject level. The mean RNFL thickness was 1.94 µm (LOA: −5.74 to 9.62 µm) higher on Spectralis compared to Cirrus HD-OCT, indicating excellent agreement for this measurement across this cohort. Although these data indicate that these three devices agree poorly at an individual subject level (evidenced by wide LOA in both study cohorts) precluding their co-utilization in everyday practice, the small difference for mean measurements between Cirrus HD-OCT and Spectralis indicate pooled results from these two SD-devices could be used as outcome measures in clinical trials, provided patients are scanned on the same machine throughout the trial, similar to the utilization of multiple different MRI platforms in MS clinical trials.

Relationships between quantitative spinal cord MRI and retinal layers in multiple sclerosis

“…10,11 Peripapillary and macular data were obtained with the Optic Disc Cube 200 3 200 and Macular Cube 512 3 128 protocols, respectively. Experienced technicians performed optical coherence tomography (OCT) scans, which were monitored to ensure reliable fixation.…”

Active MS is associated with accelerated retinal ganglion cell/inner plexiform layer thinning

“…Retinal imaging was performed using Cirrus HD-OCT (model 4000) with software version 5.0 (Carl Zeiss Meditec, Dublin, CA), as described in detail elsewhere. 26 Peripapillary data were obtained with the Optic Disc Cube 200 3 200 protocol. Macular data were obtained using the Macular Cube 512 3 128 protocol.…”

Color-Code Agreement Among Stratus, Cirrus, and Spectralis Optical Coherence Tomography in Relapsing-Remitting Multiple Sclerosis With and Without Prior Optic Neuritis

“…There are significant differences among commercially available OCT devices in RNFL thickness measurements in patients with ON and/or relapsingremitting multiple sclerosis, so that RNFL measurements cannot be directly compared. [3][4][5][6] Clinicians should be aware that measurements are generally higher with Stratus than with Cirrus, 4,5 except at thinner RNFL values, and slightly higher on Spectralis compared to Cirrus OCT. 3,6 OCT provides information on probable RNFL defects as 4 color codes through comparison of the RNFL profile with an internal age-matched normative database. Recently, Kim and associates 7 evaluated the color-code agreement between Cirrus and Stratus OCT in patients with glaucoma, and they concluded that color codes were not interchangeable.…”