This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Magnetic Resonance Imaging, Subject name: Radiology
[{'content': 'Which sequence of MRI is used to detect microhemorrhages? \nSelect and explain. \nA. T1WI, B. T2WI, C. SWI, D. DWI', 'role': 'user'}, {'content': 'Answer: C \nExplanation: SWI (Susceptibility-Weighted Imaging ) is a relatively new full-velocity compensated high-resolution 3-dimensional gradient echo sequence that accurately detects small hemorrhage (microhemorrhage) and calcification by exaggerating susceptibility signal intensity, which is more sensitive than T2 gradient echo.', 'role': 'assistant'}]