As FOV increases, what happens to SNR?

When the field of view (FOV) increases, the signal-to-noise ratio (SNR) typically decreases. This relationship can be attributed to the way that a larger FOV affects the volume of tissue being sampled and the distribution of noise in the image.

In medical imaging, SNR is crucial as it impacts the quality of the images obtained. With an increase in FOV, the same number of signal elements is spread over a larger area. This means that while the signal may increase (because more tissue is being included), the noise, which is typically uniform across the entire area, does not increase at the same rate. Therefore, the overall effect can dilute the SNR, leading to lower quality images

Also, a larger FOV may encompass more areas of low signal or surround it by more noise from edges or other anatomical structures, causing a decrease in the clarity and quality of the final image produced. Therefore, understanding this relationship between FOV and SNR is vital for optimizing imaging techniques and ensuring that the quality of diagnostic images is maintained.