Efficient reduction of speckle noise in Optical Coherence Tomography

Area of Science:

• Biomedical Optics
• Medical Imaging Technology

Background:

• Speckle patterns in Optical Coherence Tomography (OCT) degrade image resolution and quality.
• Existing speckle reduction methods are often unsuitable for real-time in vivo applications due to motion sensitivity or complexity.

Purpose of the Study:

• To develop a robust and simple speckle reduction technique for OCT.
• To improve the applicability of OCT for in vivo imaging.

Main Methods:

• Non-coherent averaging of OCT A-scans acquired from adjacent sample locations.
• Utilizing a scanning protocol with fast beam deflection and an ultrahigh-speed CMOS camera.
• Implementing a dedicated A-scan generation algorithm for real-time processing.

Main Results:

• Successfully reduced speckle contrast in OCT images.
• Achieved real-time image display at 6 frames per second.
• Demonstrated immunity to sample motion and eliminated the need for complex alignment procedures.

Conclusions:

• The proposed A-scan averaging technique effectively reduces speckle in OCT.
• This method is suitable for real-time, in vivo imaging of biological tissues, including the human eye and skin.
• The technique offers a practical alternative to existing speckle reduction methods.