MRI Physics Chapter 6 Questions and Answers Already Passed

MRI Physics Chapter 6 Questions and Answers Already Passed Why does gadolinium enhance MRI images? It shortens T1 relaxation, increasing signal intensity How does TR affect T1 contrast? Short TR values enhance T1 contrast What happens if the slice gap is too small in multi-slice imaging? It can cause signal interference between slices How does increasing gradient strength affect diffusion-weighted imaging? It enhances sensitivity to water movement in tissues Why is echo-planar imaging (EPI) useful in MRI? It allows rapid acquisition of images in a single shot 2 What is the effect of using a longer TE in T2-weighted imaging? It increases T2 contrast but decreases overall signal How does a spin-echo sequence correct for dephasing? By using a 180-degree refocusing pulse Why is spatial resolution important in MRI? It determines the level of detail in the final image What is the significance of phase encoding? It assigns spatial location to signals in an image How does field of view (FOV) affect resolution? A larger FOV lowers resolution but captures more anatomy Why are ultra-short TE sequences used in MRI? To capture signals from tissues with very short T2 times 3 What is the primary function of a time-of-flight (TOF) sequence? To enhance visualization of blood flow without contrast What is the primary function of RF coils in MRI? To transmit and receive radiofrequency signals How does increasing TR affect image contrast? It reduces T1 contrast and increases scan time What happens when TE is increased in a spin-echo sequence? It enhances T2 contrast but reduces SNR Why is T2* decay faster than T2 decay?