Which diagnostic imaging modality is best for evaluating the brain and spinal cord?
Correct Answer: D
Magnetic resonance imaging (MRI) provides the most sensitive and detailed images of the brain and spinal cord when compared to other modalities. It is superior for soft tissues and less useful for most bone and air-filled structures.
Computed tomography (CT) is most sensitive for bone and air-filled structures, such as the nasal cavity and middle ear. Since CT images are formulated by computer processing numerous radiographs, it is more detailed than routine survey radiography at all tissue types. CT can provide some information about the brain and spinal cord, but is limited when compared to MRI.
Ultrasound waves cannot penetrate through mineralized bone, making ultrasound a modality reserved for soft tissue only.
Nuclear scintigraphy is most commonly used for bone, thyroid, portal vessels, and lymph node tissues.