In MRI, the terms T1 and T2 time constants are crucial for obtaining suitable weighted images. Choose the correct explanation.
Show Hint
T2 → transverse decay.
- T1 is the spin-lattice or longitudinal relaxation time, and T2 is the spin-spin or transverse relaxation time
- T1 and T2 indicate durations of FID signals in x and y directions
- T1 and T2 refer to flipping pulse durations
- T1 is transverse relaxation time, and T2 is longitudinal relaxation time
The Correct Option is A
Solution and Explanation
Step 1: Understanding T1 Relaxation
T1 relaxation is the recovery of longitudinal magnetization along the main magnetic field. It involves energy transfer between nuclei and the surrounding lattice (spin-lattice relaxation).
Step 2: Understanding T2 Relaxation
T2 relaxation represents the decay of transverse magnetization as spins lose phase coherence. This is due to interactions among spins, hence called spin-spin relaxation.
Step 3: Eliminating Wrong Options
- T1 and T2 are not FID durations nor RF pulse durations.
- Option (D) reverses the definitions.
Thus, option (A) is the only correct statement.
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