Magnetic Resonance Imaging (MRI) Practice Test

What should the acquisition voxel be to produce a high-quality reformatted image?

1. Unisotropic

2. Anisotropic

3. Isotropic

4. Homogeneous

The correct answer is: Isotropic

Choosing isotropic voxels is essential for generating high-quality reformatted images in MRI. Isotropic voxels have equal dimensions in all three spatial directions, which leads to uniformity and consistency in the image. This uniformity allows for accurate measurements and reformatting in any plane without introducing distortions or artifacts, which can occur with anisotropic voxels, where dimensions differ across axes. When isotropic voxels are utilized, the reformatted images maintain the same level of clarity and detail regardless of the orientation, which is particularly important in clinical settings where precise anatomical relationships and pathologies need to be visualized effectively. In contrast, anisotropic voxels may provide high resolution in one direction while sacrificing resolution in others, which can lead to loss of important details when the images are reformatted. While homogeneous refers to uniformity in a different context, it does not specifically pertain to the dimensions of the voxel itself. Thus, isotropic is the preferable choice for achieving high-quality reformatted images in MRI.