Enhanced joint spectral and time domain optical coherence tomography for quantitative flow velocity measurement

Research output: Contribution to book/conference proceedings/anthology/reportConference contributionContributedpeer-review

Abstract

Recently, a new method called joint spectral and time domain optical coherence tomography (STdOCT) for flow velocity measurement in spectral domain OCT (SD OCT) was presented. This method analyzes the detected timeresolved interference fringe spectra by using a two-dimensional fast Fourier transformation (2D FFT) to determine directly the Doppler frequency shift instead of calculating the phase difference at each depth position of adjacent A-scans. There, it was found that STdOCT is more robust for measurements with low signal to noise ratio than the classic phase-resolved Doppler OCT (DOCT) making it attractive first for imaging fast flow velocities at which a strong Doppler angle dependent signal damping occurs due to interference fringe washout and second for investigating large blood vessels with a big diameter and a highly damped signal of blood with increasing depth due to strong scattering and absorption in the near-infrared wavelength range. In the present study, we would like to introduce an enhanced algorithm for STdOCT permitting a more precise flow velocity measurement in comparison to the conventional STdOCT. The new method determines the amplitude of the broadened Doppler frequency shift by calculating the center of gravity via the complex analytical signal as a result of the second FFT instead of detecting the maximum intensity signal. Furthermore, the comparison with phase-resolved DOCT was done experimentally by using a flow phantom consisting of a 1% Intralipid emulsion and a 320 μm glass capillary. As a result, the enhanced STdOCT and DOCT processed data are completely equivalent.

Details

Original languageEnglish
Title of host publicationOptical Coherence Tomography and Coherence Techniques V
Publication statusPublished - 2011
Peer-reviewedYes

Publication series

SeriesProgress in Biomedical Optics and Imaging - Proceedings of SPIE
Volume8091
ISSN1605-7422

Conference

TitleOptical Coherence Tomography and Coherence Techniques V
Duration24 - 26 May 2011
CityMunich
CountryGermany

External IDs

Scopus 79960796413
ORCID /0000-0003-0554-2178/work/142249854
ORCID /0000-0003-2292-5533/work/142256593

Keywords

Keywords

  • advanced interferometry, flow measurement, non-invasive imaging technique, oblique sample motion, phase-resolved Doppler analysis, random scattering sample, spectral domain optical coherence tomography