Image Artifacts in Optical Coherence Tomography Angiography Among Patients With Multiple Sclerosis.

PURPOSE

To evaluate artifacts in optical coherence tomography angiography (OCT-A) images of multiple sclerosis (MS) patients and healthy controls.

MATERIALS AND METHODS

This was a prospective cross-sectional study conducted at the Department of Neurology and the Wilmer Eye Institute at Johns Hopkins Hospital. Subjects included patients with an established diagnosis of MS and healthy volunteers. OCT-A was performed using Spectralis® OCT-A prototype, OCT2 (Heidelberg, Germany). The type and frequency of artifacts, the clinical factors associated with them, and their impact on vessel density measurements were assessed.

RESULTS

Overall, 385 images from 102 participants were analyzed. The majority of images (97.1%) had some degree of artifact. The most frequent was motion artifact (96.3%), followed by blinking (51.9%), and loss of focus (25.1%). MS patients were more likely to have any artifact vs. controls (OR [95% CI], 3.83 [1.12-12.92]), and were more likely to have motion artifacts with longer disease duration (OR [95% CI], 1.11 [1.03-1.20]) or history of optic neuritis (OR [95% CI], 4.24 [1.19-15.16]). The relative area occupied by the artifact was found to underestimate vessel density measurements in both MS patients and controls.

CONCLUSIONS

Artifacts are common with OCT-A imaging using this particular Spectralis® OCT-A prototype and can impact quantitative vascular density metrics. Future studies should review images for artifacts before drawing definitive conclusions.