Which tissue is likely to have the fewest protons detectable by MRI?

The tissue that is likely to have the fewest protons detectable by MRI is the femur, primarily due to its composition and structure.

MRI relies on the presence of hydrogen protons, which are abundant in tissues with higher water content or fat content. The femur, being a bone, has a much lower density of water and is primarily composed of mineralized extracellular matrix, which contains less hydrogen compared to soft tissues. This reduced number of protons reflects a weaker MRI signal, making it harder to detect, especially compared to other tissues like muscle or organs filled with fluids.

In contrast, tissues such as the kidney, eyes, and biceps contain higher amounts of water or fat, resulting in significantly more protons. The kidneys, for instance, are highly vascularized and have a substantial water content, providing a strong signal on MRI scans. The eyes, while having some unique structures, still contain fluids that contribute to their proton density. The biceps, as a muscle, are also rich in water and, therefore, would emit a strong signal due to the high number of protons present.

Overall, this understanding of the composition and characteristics of different tissues explains why the femur is the tissue with the fewest detectable protons