The brain is the most complex organ in the human body. However, MRI has taken those advances several levels higher and has replaced CT as the imaging modality of choice for most disorders of the nervous system. Other pathologic processes include hemorrhage, vascular abnormalities, and pituitary and sellar masses. It should be noted that CT still has a primary role in imaging the patient with an acute neurologic event. The tumor itself is of varying intensity on different MR images, but frequently shows enhancement from contrast.
Early detection has a considerable effect on treatment and prognosis.
MRI with contrast is considerably more sensitive than CT for the detection of cerebral metastases. The lesions often are invisible without contrast and therefore it is imperative that all cancer patients have MR of the brain performed with intravenous contrast. As newer treatment options are being developed, the early and accurate diagnosis of stroke becomes more critical. MRI is the imaging modality of choice for the detection of cerebral infarction, and also provides vital information concerning the size and location of the infarct. Although not used in this case, intravenous contrast is usually administered in the evaluation of infarction since it can both aid in the detection of an early infarct and can help determine the age of the infarct.