Which of the following three parameters control the size of a voxel and image spatial resolution?

• A. FOV, matrix, slice thickness
• B. TR, NEX, slice thickness
• C. Bandwidth, TR, FOV
• D. Receiver bandwidth, TR, matrix

Answer: (A)

The size of a voxel and image spatial resolution are fundamentally influenced by three parameters: field of view (FOV), matrix size, and slice thickness.

Field of view determines the extent of the area being imaged. A larger FOV will generally lead to a larger voxel size, while a smaller FOV allows for finer resolution but captures a smaller area.

The matrix size refers to the number of pixels used in the image, both in the horizontal and vertical directions. A higher matrix size increases the number of pixels in the same FOV, effectively reducing the size of each voxel and allowing for finer spatial resolution in the resulting image.

Slice thickness is a critical factor that influences the volume each voxel represents. Thinner slices yield smaller voxels, thus improving the spatial resolution. However, thinner slices might also increase noise in the images as the signal from the tissue is spread over a smaller volume.

By adjusting FOV, matrix, and slice thickness, MRI technologists can optimize image quality and resolution, making it essential to have a thorough understanding of these parameters when preparing for imaging.