Contrast Perfusion MRI

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Above color maps are from MRI Dynamic Susceptibility Contrast Perfusion (DSCP) study of the patient with follow-up after resection and radiotherapy of the parieto-occipitally located Anaplastic Astrocytoma eight years ago. There is no recurrent tumor - only gliosis. Sometimes DSCP can help in characterization of the  enhancement pattern of rest or recurrent tumor to differentiate if from radiation necrosis. This case has no contrast enhancement. Reason for this blog post is to mention this interesting MRI technique that I hope to expand on in the future.
What we see are the color maps representing:
TTP (Time To Peak) - that shows the regional distribution of arrival time of the bolus in the tissue
CBF (Cerebral Blood Flow)
CBV (Cerebral Blood Volume)
MTT (Mean Transit Time)

Above are T2, FLAIR and contrast enhanced T1 sequences from the same region as presented on the Perfusion maps. Note gliosis, tissue atrophy and lack of enhancement.
Images from 3 Tesla scanner.

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