Fig. 2.

(a) Measured signal from one of the volunteers showing a more rapid signal decay in the thyroid gland at very small b-values (<70) with subsequent equalization of the decay slope to muscle tissue leading to a nearly constant difference between the two curves. (b) Exemplary multi-step fitting approach on the thyroid signal data. Note the different scale. The optimal b-value threshold determined by the smallest sum of squared differences from the measured points to the curve was a b-value of 20 s/mm² highlighted in red and bold, which seems to optimally reflect the early steep signal decay.