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

Area of Science:

• Ophthalmology
• Neurology
• Medical Imaging

Background:

• Optical coherence tomography angiography (OCT-A) is a key imaging technique for visualizing retinal vasculature.
• Understanding image quality and potential artifacts is crucial for accurate interpretation, especially in neuro-ophthalmic diseases like multiple sclerosis (MS).

Purpose of the Study:

• To evaluate the prevalence and types of artifacts in OCT-A images of multiple sclerosis (MS) patients and healthy controls.
• To identify clinical factors associated with these artifacts.
• To assess the impact of artifacts on quantitative vessel density measurements.

Main Methods:

• Prospective cross-sectional study involving 102 participants (MS patients and healthy controls).
• OCT-A imaging performed using a Spectralis® OCT-A prototype (Heidelberg, Germany).
• Analysis of 385 images to categorize artifact types, frequency, and assess impact on vessel density.

Main Results:

• A high prevalence of artifacts (97.1%) was observed across all images.
• Motion artifact was the most frequent (96.3%), followed by blinking (51.9%) and loss of focus (25.1%).
• MS patients showed a higher likelihood of artifacts, particularly motion artifacts, associated with longer disease duration and optic neuritis history. Artifacts were found to underestimate vessel density measurements.

Conclusions:

• Artifacts are prevalent in OCT-A imaging with the Spectralis® prototype and can significantly impact quantitative vascular density metrics.
• Careful image review for artifacts is essential before drawing conclusions from OCT-A studies, especially in MS populations.
• Further research may be needed to refine artifact detection and mitigation strategies in OCT-A.