There are different parameters that have direct influence on the resolution of an image. Voxel size is one of the most important parameters; however, field of view, scan time, number of basis images and type of detector also influence the resolution and quality of the scan. The longer the acquisition time, the more basis images are available. If a small voxel size is chosen the result will produce high spatial resolution but the amount of radiation exposure to the patient will be increased. These parameters change according to each patient situation. If a pediatric patient or an elderly patient has difficulty remaining still, a faster scan time might be the more appropriate way to evaluate a certain condition, resulting in decreased image resolution. As a general rule, the smaller the voxel size the higher the resolution.