Speckle reduction in optical coherence tomography images by use of a spatially adaptive wavelet filter

• Published in: Optics letters 2004-12, Vol.29 (24), p.2878-2880
• Main Authors: ADLER, Desmond C, KO, Tony H, FUJIMOTO, James G
• Format: Article
• Language: English
• Subjects: Algorithms; Artificial Intelligence; Biological and medical sciences; Exact sciences and technology; Feasibility Studies; Fundamental and applied biological sciences. Psychology; Fundamental areas of phenomenology (including applications); General aspects, investigation technics, apparatus; Image Enhancement - instrumentation; Image Enhancement - methods; Image forming and processing; Image Interpretation, Computer-Assisted - instrumentation; Image Interpretation, Computer-Assisted - methods; Imaging and optical processing; Optics; Physics; Reproducibility of Results; Retina - cytology; Sensitivity and Specificity; Speckle and moire patterns; Tissues, organs and organisms biophysics; Tomography, Optical Coherence - instrumentation; Tomography, Optical Coherence - methods
• ISSN: 0146-9592; 1539-4794
• DOI: 10.1364/ol.29.002878

A spatially adaptive two-dimensional wavelet filter is used to reduce speckle noise in time-domain and Fourier-domain optical coherence tomography (OCT) images. Edges can be separated from discontinuities that are due to noise, and noise power can be attenuated in the wavelet domain without significantly compromising image sharpness. A single parameter controls the degree of noise reduction. When this filter is applied to ophthalmic OCT images, signal-to-noise ratio improvements of >7 dB are attained, with a sharpness reduction of