Trade Offs

As you may have gathered from reading up to this point, the SNR, resolution, and acquisition time, are all interrelated. Changing one effects the others. One job of yours as a radiologist may be to decide what factors are more important for an examination of a particular body part or patient. When looking at the pituitary or cranial nerves, for example, you may want to sacrifice some SNR or longer acquisition time for improved spatial resolution. On the other hand, in a claustrophobic of patient in pain who may be moving around, you may sacrifice both resolution and SNR for the shortest possible examination time. A table is available to summarize the trade offs between SNR, resolution, time, maximum number of slices and distance covered.