blind source-separation for heart wall and erythrocyte motion estimation in the beating embryonic...

Blind Source-Separation for Heart Wall and Erythrocyte Motion Estimation in the Beating Embryonic Heart

Sandeep BhatSystems Bioimaging Lab, UCSBPresentation for ENGR 103, Nov 20, 2008

sandeepkbhat@ece.ucsb.edu

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Agenda

• Motivation• Problem Setup• Algorithm stages• Results• Conclusion

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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.

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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)

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Algorithm Stages

• Three stages:

– Pre-processing

– Separation algorithm

– Post-processing

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Separation Algorithm

• Temporal alignment

• Heart-wall:

– “Periodic”

– Mean/Median filtering

• Red Blood Cells:

– Not periodic

– Subtraction/Variance

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• Flow analysis using FlowJ

Post-processing

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Results• frequency components. • Testing with synthetically generated data.• Testing with synthetically generated data.

• (a) Mean+Subtraction (b) Mean+Variance

• (c) Median+Subtraction (d) Median+Variance

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Results (contd.)• BFM images of zebrafish heart

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Conclusion