Decreasing the field of view increases spatial resolution but decreases which of the following?

• A. SNR
• B. Image quality
• C. Scan speed
• D. Patient comfort

Answer: (A)

Decreasing the field of view (FOV) indeed increases spatial resolution, allowing finer detail to be visualized in the image. However, one consequence of reducing the FOV is the effect it has on the signal-to-noise ratio (SNR).

When the FOV is decreased, the area being imaged is smaller, which can lead to a decrease in the amount of signal received relative to the amount of noise present in the image. The SNR is critical in imaging because a higher ratio indicates clearer images with less noise, while a lower SNR can lead to images that are grainy or less discernible. Thus, while fine detail may become more prominent with reduced FOV, the accompanying decrease in SNR generally results in a compromise in overall image quality.

In MRI, optimizing both spatial resolution and SNR is essential for producing high-quality diagnostic images, and understanding this trade-off is crucial for effective imaging practice.