SNR is proportional to voxel volume. If you want to increase SNR by adjusting only one parameter, which change increases voxel volume?

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Multiple Choice

SNR is proportional to voxel volume. If you want to increase SNR by adjusting only one parameter, which change increases voxel volume?

Voxel volume controls SNR because the MR signal comes from the spins within a voxel, so larger voxels capture more signal. SNR scales with the square root of voxel volume, meaning increasing volume boosts SNR, while reducing it lowers SNR. To increase voxel volume by changing only one parameter, you would increase slice thickness—the thicker the slice, the larger the voxel along the slice direction. This raises SNR but at the cost of lower spatial resolution and more partial-volume effects. The other adjustments either shrink voxel size (decreasing slice thickness, increasing matrix size, or decreasing FOV) and thus reduce SNR, or alter resolution rather than volume.

Voxel volume controls SNR because the MR signal comes from the spins within a voxel, so larger voxels capture more signal. SNR scales with the square root of voxel volume, meaning increasing volume boosts SNR, while reducing it lowers SNR. To increase voxel volume by changing only one parameter, you would increase slice thickness—the thicker the slice, the larger the voxel along the slice direction. This raises SNR but at the cost of lower spatial resolution and more partial-volume effects. The other adjustments either shrink voxel size (decreasing slice thickness, increasing matrix size, or decreasing FOV) and thus reduce SNR, or alter resolution rather than volume.

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