Time Series

Question 1

What and Why time series?

Answer 1

• image sequences
• some physiological processes can require more than static images to be analyzed (blood flow, motion of organ, contrast agent uptake)

Question 2

Perfusion Analysis

Answer 2

• plot intensity voxel over time to create an uptake curve
• correction for motion important because otherwise time curves mix different voxels
• motion correction

Question 3

Registration of time Series

Answer 3

• extension to image-to-image registration

- reference: single image, pairwise registration, global optimization (3d), synthetic reference

Question 4

relative and absolute transformations

Answer 4

• relative: transformation between time points

- absolute: transformation wrt reference time point

Question 5

propagation of uncertainty

Answer 5

• problem arises when chaning transformations
• how can it be reduced?
• minimize uncertainty in individual measurements
• correct transformation after propagating one step
• use an aggregated and regularized transformation

Question 6

Motion Analysis

Answer 6

• transformation express motion of structures in the image
• strain: deformation by force
• euler: look at spatial and what material passes through
• lagrangian: follow material point

Question 7

rigid and non rigid motion

Answer 7

• rigid: rotation & Translation

- non-rigid: scaling & shearing