Final answer:
T1-weighted MRI images use a TR range of 400-600 ms and a TE range of 10-20 ms to enhance image contrast, with relaxation times depending on tissue type and status.
Step-by-step explanation:
The student's question relates to the optimal repetition time (TR) and echo time (TE) settings for T1-weighted magnetic resonance imaging (MRI). In T1-weighted imaging, which is utilized for enhancing contrast in images, the typical TR range is 400-600 ms and the TE range is often 10-20 ms. These ranges can vary based on the MRI system used, the body part being imaged, and the specific diagnostic requirements.
T1-weighted images provide excellent contrast between different tissues, making them particularly useful for imaging the central nervous system, detecting acute hemorrhage, and characterizing focal liver lesions.
Relaxation time is a key concept in MRI, referring to the time it takes for protons to return to their equilibrium state after the external magnetic field is turned off. T1 relaxation time varies depending on the type of tissue and its condition, such as the presence of inflammation, which can influence the choice of TR and TE settings for optimal imaging.