Fig. 3.

Normalized speckle decorrelation curves of a fibrous plaque during stationary and moving conditions using (a) an angioscope, and (b) a leached fiber bundle. In (a), the angioscope showed larger differences in speckle decorrelation curves during motion, resulting in an error of over 80% in measuring time constants. The speckle decorrelation curve shown in grey was significantly modulated by cardiac motion, as shown in the plot. In (b), the speckle decorrelation curves obtained from the leached fiber bundle measured under moving conditions corresponded well with measurements under stationary conditions. The error in measuring time constant of the fibrous plaque was 7% using the leached fiber bundle.