MR Susceptibility GRE
Claim CME CreditPOINT OF CARE INFORMATION
This CME activity consists of the student reviewing the video of the professor reviewing the case as well as the associated DICOM image set related to the case in question.
Learning Objectives
As a result of participation in this activity, participants should be able to:
- Provide improved patient care.
- Greater knowledge of the imaging characteristics of the patient's disease.
- Understand a better approach to interpretation of studies.
Faculty Disclosure
Mehmet Albayram, MD, Ivan Davis, MD, Mariam Hanna, MD, Anthony Mancuso, MD, Ronald Quisling, MD, Dhanashree Rajderkar, MD, Priya Sharma, MD, Roberta Slater, MD and Joann Stamm, MBA have disclosed that they have no relevant financial relationships. No one else is a position to control content have any financial relationship to disclose.
CME Advisory Committee Disclosure:
Conflict of interest information for the CME Advisory Committee members can be found on the following website: https://cme.ufl.edu/disclosure/.
Continuing Medical Education Credit
Accreditation: The University of Florida College of Medicine is accredited by the Accreditation Council for Continuing Medical Education (ACCME) to provide continuing medical education for physicians.
Credit: The University of Florida College of Medicine designates this enduring material for a maximum of 0.5 AMA PRA Category 1 Credits. Physicians should claim only the credit commensurate with the extent of their participation in the activity.
CA0368-MR Susceptibility GRE
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CA0368-MR Susceptibility GRE
Case ReportExam
Prior Study
1. Distal segment basilar artery partially occlusive acute thrombosis is present with mainly circle of Willis collateral to distal basilar tip and PCA trunks. Thus, there is filling of all pial arteries although limited on the left.
2. There is significantly reduced CT density in the venocapillary pool in the subcortical mesial occipital white matter bilaterally (dense ischemic core). Findings are most consistent with ischemic injury associated with the initial thromboembolic event. Currently there has been significant recanalization of the distal P4 arteries (better on the right) and partial clot lysis in the distal basilar artery. The depth and duration of the initial ischemic insult resulted in deep white matter occipital stroke.
2. Limited filling the left PICA resulting in completed stroke involving the mesial (caudal) cerebellum (dense ischemic core) and lesser ischemic changes in the remaining left lateral cerebellum (likely in the ischemic penumbra).
Findings for diffusion: DWI/ADC maps
The diffusion maps (both DWI and ADC) are positive for hyperacute stroke in both mesial occipital areas (P4 PCA perfusion zones).
There are separated small DWI positive areas in the right occipital lobe, which again are consistent with recent secondary emboli.
The diffusion maps (both DWI and ADC) are positive for stroke in the mesial left cerebellum and left peritonsillar region corresponding to the peritonsillar and mesial hemispheric trunks of the Lt. PICA.
Findings for FLAIR
1. Recent FLAIR positive ischemic events in multiple sites including the mesial occipital lobes (P4 segment PCA perfusion zones) and in the Lt PICA (affecting the mesial cerebellar and peritonsillar trunks only). Stroke-ages are variable, as above.
2. Embolic source is likely (originally) thrombus in the left intradural vertebral artery segment based on FLAIR findings. This original thrombus likely occluded the left PICA resulting in mesial left cerebellar infarction, which is why this stroke is older than the others.
Findings
MR susceptibility
GRE demonstrates phase artifact (representing hemosiderin or deoxyHgb) in the post medullary segment of the left PICA and in the distal basilar thrombus.
There is no hemorrhagic conversion.
Two other areas of abnormal signal are evident in the cerebrum from previous ischemic events with chronic microhemorrhage; one is in the left caudate head region and the other is in the high convexity left lateral cortex. Both are chronic changes.
Impression
2. There is no hemorrhagic conversion. There are small sites of prior parenchymal chronic blood products of no acute significance.
Recommendations
A video discussion of all CT, CTA, and MR elements is available, which reviews all the pertinent findings and summarizes their importance in this clinical case.
