What is a primary benefit of increasing NEX in MRI?

Increasing the number of excitations per acquisition, or NEX, fundamentally enhances the signal-to-noise ratio (SNR) in MRI by allowing for more signal averaging. When multiple acquisitions of the same data are averaged together, any random noise present in the signal is reduced relative to the true signal, leading to clearer and more discernible images. The result is higher image quality with improved detail, facilitating better visualization of anatomical structures and potential abnormalities.

While increasing NEX can lead to longer scan times and does not inherently improve spatial resolution or decrease the coverage of anatomy, the key advantage lies in its ability to provide more robust and reliable images through enhanced signal averaging. This principle is crucial in MRI techniques where noise can significantly impact diagnostic outcomes.