Blind Source-Separation for Heart Wall and Erythrocyte Motion Estimation in the Beating Embryonic Heart Sandeep Bhat Systems Bioimaging Lab, UCSB Presentation for ENGR 103, Nov 20, 2008

2 Agenda Motivation Problem Setup Algorithm stages Results Conclusion

3 Motivation Study of model organisms – Embryonic development, toxicology, specific gene function. – Zebrafish embryo is transparent Live imaging of embryos. – Fluorescence microscopy (FM) – Bright field microscopy (BFM) The algorithm aids BFM imaging of developing zebrafish heart.

4 Problem Setup Input: BFM image sequence – Spanning several cardiac cycles. Desired output: Two image sequences – Spanning one period (cardiac cycle) – One showing only the heart morphology – The other with only the transient structures (Red Blood Cells) ‏

5 Algorithm Stages Three stages: – Pre-processing – Separation algorithm – Post-processing

6 Separation Algorithm Temporal alignment Heart-wall: – “Periodic” – Mean/Median filtering Red Blood Cells: – Not periodic – Subtraction/Variance

7 Flow analysis using FlowJ Post-processing

8 Results frequency components. Testing with synthetically generated data. (a) Mean+Subtraction (b) Mean+Variance (c) Median+Subtraction (d) Median+Variance

9 Results (contd.) BFM images of zebrafish heart

10 Conclusion