Microangiography method and system based on full-space modulation spectrum splitting and angle compounding
A microangiography method and system based on full-space modulation spectrum splitting and angle compounding is disclosed. Label-free three-dimensional optical coherence tomography angiography is realized by combining the three-dimensional space resolution capability of an optical coherence tomography and the motion recognition capability of a dynamic scattering technology. Probe light of different incident angles is encoded with a transverse scanning modulation spectrum in a spatial frequency domain, incident angle-resolved sub-angiograms which are independent of one another are obtained by splitting the modulation spectrum, and an angiogram with multiple space angles compounded is realized. Conjugate mirror images are removed from a depth (z) domain, a complex-valued OCT interference spectra are reconstructed, the full-space modulation spectrum is obtained in the spatial frequency domain, and the overlap of the modulation spectrum conjugate mirror images is avoided. And the absolute flow velocity of blood flow can be measured through a multi angle-resolved probing technology.
1. A microangiography method based on full-space modulation spectrum splitting and angle compounding, comprising following steps of:
1) reconstructing complex-valued interference spectrum and obtaining a full-space transverse scanning modulation spectrum in a spatial frequency domain by removing conjugate mirror images in an OCT (Optical Coherence Tomography) depth (z) domain;
2) encoding a probe light of different incident angles with the full-space transverse scanning modulation spectrum in the spatial frequency domain and obtaining an incident angle-resolved OCT interference subspectra independent of one another by splitting a modulation spectrum;
3) obtaining independent sub-angiograms of multi-angle-resolved based on transverse scanning modulation spectrum splitting by combing a modulation spectrum splitting technology and an optical coherence tomography angiography technology in the step 2);
4) obtaining multi angle-resolved independent sub-angiograms based on full-space transverse scanning modulation spectrum splitting by combining a full-space modulation spectrum in the step 1) and the modulation spectrum splitting technology and the optical coherence tomography angiography technology in the step 2), and
5) averaging the sub-angiograms obtained in the step 3) or the step 4) to get a angiogram with multiple space angles compounded.
2. The microangiography method based on the full-space modulation spectrum splitting and angle compounding, as recited in claim 1 , wherein a multi angle-resolved absolute flow velocity of blood flow is measured based on the transverse scanning modulation spectrum splitting through the modulation spectrum splitting technology in the step 2).
3. The microangiography method based on full-space modulation spectrum splitting and angle compounding, as recited in claim 1 , wherein a multi-angle-resolved absolute flow velocity of blood flow is measured based on the full-space transverse scanning modulation spectrum splitting through the full-space modulation spectrum in the step 1) and the modulation spectrum splitting technology in the step 2).