A 55-year-old patient with a history of hypertension presents with a sudden severe headache. An MRI brain is performed to rule out intracranial hemorrhage. Which MRI sequence is most sensitive for detecting acute and chronic hemorrhage, as well as microbleeds, due to its susceptibility to magnetic field inhomogeneities caused by blood products?

Explanation

Gradient Recalled Echo (GRE) sequences are highly sensitive to magnetic susceptibility effects, making them ideal for detecting hemorrhage (acute, subacute, and chronic), calcifications, and hemosiderin deposits (microbleeds). Blood products like deoxyhemoglobin and methemoglobin cause local magnetic field inhomogeneities, leading to signal loss (dark areas) on GRE images. Susceptibility-Weighted Imaging (SWI) is an advanced form of GRE that further enhances this sensitivity.