Interplane bulk motion analysis and removal based on normalized cross-correlation in optical coherence tomography...

Area of Science:

• Biomedical Imaging
• Optical Coherence Tomography Angiography (OCTA)
• Medical Image Processing

Background:

• Bulk motion, particularly perpendicular to B-scans, is a major source of image degradation in OCTA.
• Existing correction methods primarily address in-plane motion, neglecting out-of-plane artifacts.
• Interplane bulk motion noise reduces the sensitivity and quality of cross-sectional OCTA images.

Purpose of the Study:

• To evaluate the impact of interplane bulk motion on OCTA image quality.
• To develop and validate a novel repetitive bulk motion correction method for OCTA.
• To improve the diagnostic utility of OCTA by reducing motion-induced noise.

Main Methods:

• Quantification of interplane bulk motion using a specific scan protocol and cross-correlation analysis.
• Development of a repetitive bulk motion correction technique utilizing estimated displacements and redundant volume scans.
• In vivo experimental validation using OCTA imaging of mice skin.

Main Results:

• The study successfully quantified the contribution of interplane bulk motion to OCTA image noise.
• The proposed repetitive bulk motion correction method effectively reduced artifacts from cardiac, respiratory, and motion events.
• OCTA images acquired with the correction method demonstrated significantly improved quality and reduced noise.

Conclusions:

• Interplane bulk motion is a critical factor affecting OCTA image quality and diagnostic sensitivity.
• The developed repetitive bulk motion correction method offers an effective solution without requiring registration or low-flow sensitivity frame reconstruction.
• This technique holds significant practical value for enhancing clinical OCTA diagnosis and analysis.