Which of the following statements is false about MRI? Spatial localization is imposed on the signal by adding to the static magnetic field a spatially varying magnetic field component that is a linear gradient along z. for slice selection, and x or y. for further local variation. The last axis, y or x. varies locally based on phase shift, b There is an interpretation in the frequency domain of the acquired signal, based on the k-space coordinates K_X and k_Y. which equates with the time integrals of the magnetic field gradients G_x and G_y. The extent of k-space that we sample, k_max is based on the largest frequency of the signal that we want to encode, assuming the signal is band-limited to frequencies less than k_max, in both axes, whereby reducing k-max reduces the ability of MRI to resolve high-frequency details. The relationship between gradients G_x-G_y and k-space coordinates k_x-k_y implies that there are many paths feasible to sample the signal in Fourier space, including spiral trajectories. None of the above statements is false. Which of the following is not a registration technique? Iterative-Closest Point. Hough Transform. Mutual Information Maximization. Singular Value Decomposition (of homologous point pairs). All of these are registration techniques. Which of the following is false about volume rendering? Volume rendering does not require prior tissue segmentation, unlike surface rendering. Volume rendering requires a means of aggregating tissue properties along a sampled path that is orthogonal to the image plane and pierces it at the pixel of interest. One strategy for aggregating tissue properties is Maximum Intensity Projection, which assigns the largest tissue voxel value (e.g. Hounsfield unit in CT). along the path, to the image pixel. In splatting, every voxel of the image volume is splatted like a snowball onto the view ing surface in front-to-back order. None of these statements is false