Figure 2.

Results of preprocessing steps for simulated data at different noise levels. The dashed line denote the simulated contrast agent curve in reference region; the crosses denote the simulated noisy data (we randomly picked one pixel for each group with different parameters); the stars denote the clustered data; and the solid curves are fitted from clustered data via Eq. 7. All the noisy data can be correctly classified into four clusters consistent with the assigned four groups. And all the fitted curves at all noise levels are consistent with that from noise free data in panel (a). The results illustrate that FCM and fitting to Eq. 7 reduce the effects of the noise.