Biomedical Engineering Reference
In-Depth Information
(b)
(a)
Figure 1.39: Real (blue) and simulated (red) gray-level vertical profile (a) of
ROIs of Fig. 1.38(b) and data correlation (b).
The maximal difference profiles are localized in the transducer sheath gray-
level distribution and the baseline of the transducer sheath inner region. These
differences can be smaller, increasing the video and instrumental noise. The
high-frequency oscillations in the gray-level profiles come from the concentric
arterial structures. We can also observe the gradual reduction of the gray-level
magnitude from intima/media interface to adventitia, caused by the ultrasound
intensity attenuation.
(b)
(a)
Figure 1.40: Global projections in the direction
θ
(a), from Figs. 1.38(b) and
(d) and the corresponding histogram gray-level differences (b).
