Structural and practical identifiability of contrast transport models for DCE-MRI
Fig 6
Study on the noise effect on parameter practical identifiability in the LTK model.
Top row: Artificial VIF obtained from the analytical expression (Eq (3)) by adding a noisy signal with increased amplitudes. No noise VIF (first subplot) is the artificial VIF used in the (AA) case, while 5%, 10%, and 15% noise VIF (second to fourth subplots) are obtained by adding noise to the noise-free VIF. Bottom row: profile likelihood and confidence levels at 68%, 80%, and 95% for the parameter Ktrans for a Type I enhancement curve obtained by repeating the study on Ktrans with the increasing noisy VIF illustrated in the top row. Red markers indicate the best-fitted value .