TABLE DES MATIÈRES
2.3.3 Quantification 3D de l’embryon de souris à ED 14.5 . . . . . . . 72
2.4 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
3 Backscattering by blood in the mouse embryo: goals and experimental deter-
mination 77
3.1 Blood and backscattering by blood . . . . . . . . . . . . . . . . . . . . . 78
3.1.1 Blood and erythropoiesis . . . . . . . . . . . . . . . . . . . . . . 79
3.1.2 Ultrasound scattering by blood . . . . . . . . . . . . . . . . . . . 80
3.1.3 Factors influencing the backscatter coefficient . . . . . . . . . . . 83
3.2 Experimental set-up description for mouse imaging . . . . . . . . . . . . 84
3.2.1 A high frequency ultrasound scanner . . . . . . . . . . . . . . . 84
3.2.2 Mice studied and apparatus of anaesthesia . . . . . . . . . . . . . 88
3.3 Experimental methodologies for the calculation of the backscatter coeffi-
cient..................................... 92
3.3.1 Experimental methodologies to estimate the backscatter
coefficient . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
3.3.2 Experimental development . . . . . . . . . . . . . . . . . . . . . 96
3.4 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104
4 Backscattering by blood in the mouse embryo: quantification of changes in
backscattering within the heart chambers during gestation 105
4.1 Protocol for obtaining blood samples and
haematology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
4.1.1 Blood samples of mouse embryo . . . . . . . . . . . . . . . . . . 106
4.1.2 Analysis of the blood samples . . . . . . . . . . . . . . . . . . . 106
4.2 Protocol for imaging the embryonic mouse heart . . . . . . . . . . . . . . 109
4.2.1 Mouse embryo imaging . . . . . . . . . . . . . . . . . . . . . . 109
4.2.2 B-scan images of the embryonic mouse heart . . . . . . . . . . . 110
4.2.3 M-mode imaging . . . . . . . . . . . . . . . . . . . . . . . . . . 113
4.3 Power spectra analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
4.3.1 Frequential parameters measured with a 400 window (256
samples) ..............................116
4.3.2 Frequential parameters measured with a 200 window (128
samples) ..............................119
4.4 Apparent integrated backscatter coefficient after corrections . . . . . . . . 119
4.4.1 Apparent integrated backscatter coefficient . . . . . . . . . . . . 119
2