MRI Compared to CT

This patient’s imaging studies show evolution of a left cerebral artery infarct on CT scan and MRI.

Computed tomography of the head done 1/7/97 shows a hyperacute infarct, which is seen only by the effacement of the cerebral sulci in the left parietal region and suggestion of loss of grey/white distinction.

T2- weighted MRI scan shows no obvious signal abnormality.

Contrast-enhanced T1-weighted image shows slightly prominent intravascular contrast enhancement within the branches of the left middle cerebral artery. Otherwise, the T1-weighted images show no obvious abnormality.

CT vs MRI - Case 1


One month later, on 2/7/97, the T2-weighted images show a typical wedge-shaped infarct in the distribution of the left middle cerebral artery.

A contrast-enhanced T1-weighted image shows asymmetric intravascular contrast enhancement. However, there is minimal parenchymal contrast enhancement of the wedge-shaped left middle cerebral artery infarct in the left parietal lobe.

Non-contrast computed tomography of the head shows a hypodense left middle cerebral artery distribution infarct involving the left parietal lobe. Minimal contrast enhancement is seen.

CT vs MRI - Case 1 part 2


Lateral radiograph of the left carotid angiogram shows complete occlusion of the left internal carotid artery with minimal collateral flow via external carotid branches.

Frontal radiograph of the left carotid angiogram shows complete occlusion of the left internal carotid artery with minimal collateral flow via external carotid branches.

CT vs MRI Case 1 Part 3


On 2/20/97, sagittal T1-weighted images show marked contrast enhancement of the left parietal infarct following contrast administration. The images also show enhancement in the occipital and temporal lobes.

Axial T2-weighted images now show minimal signal changes with linear T2-hypointensity in the gyri in the left parietal lobe, indicating minimal hemorrhagic component, but most of the signal changes of T2-weighted images have resolved. Note high signal in the cavernous carotid artery on the lowest slice, indicative of carotid occlusion.

CT vs MRI - Case 1 Part 4