Case Notes
History
51 year old female presenting with an acute left facial droop, left side weakness, and mental status change. Patient was able to be seen in the ER within 1 to 1.5 hours after the onset of symptoms.Exam
Head MR Diffusion Sequences (with DWI & ADC maps)
Purpose
1. To use the diffusion maps (DWI & ADC) to identify sites of hyperacute stroke matching an arterial zone.
2. To determine whether the positive diffusion zone matches a primary stem arterial region, a secondary stem arterial region, a trunk/division arterial region, a major branch region; or a distal arterial cortical zone, or any combination;
3. In cases where there are more than one ischemic sites to determine whether changes could be from an extra cranial embolic site, or whether they represent proximal clot lysis and subsequent distal embolization;
4. To determine whether the areas involved fit best with an embolic event or embolic shower (could be from proximal plaque or cardiac source, etc;
5. To determine whether the affected areas as recognizable as a watershed zone; usually in the context of currently patent major afferent arteries (ICA’ & vertebral arteries); there are often chronic extradural carotid or vertebral occlusions;
6. To determine whether the affected area(s) could represent stroke with an end of the line watershed pattern, based on the combination of occluded major afferent brain arteries plus incomplete circle of Willis plus any additional flow-limiting stenoses;
7. Evaluate the diffusion Bo sequence for hemorrhagic conversion.
Purpose
1. To use the diffusion maps (DWI & ADC) to identify sites of hyperacute stroke matching an arterial zone.
2. To determine whether the positive diffusion zone matches a primary stem arterial region, a secondary stem arterial region, a trunk/division arterial region, a major branch region; or a distal arterial cortical zone, or any combination;
3. In cases where there are more than one ischemic sites to determine whether changes could be from an extra cranial embolic site, or whether they represent proximal clot lysis and subsequent distal embolization;
4. To determine whether the areas involved fit best with an embolic event or embolic shower (could be from proximal plaque or cardiac source, etc;
5. To determine whether the affected areas as recognizable as a watershed zone; usually in the context of currently patent major afferent arteries (ICA’ & vertebral arteries); there are often chronic extradural carotid or vertebral occlusions;
6. To determine whether the affected area(s) could represent stroke with an end of the line watershed pattern, based on the combination of occluded major afferent brain arteries plus incomplete circle of Willis plus any additional flow-limiting stenoses;
7. Evaluate the diffusion Bo sequence for hemorrhagic conversion.
Prior Study
CT HeadAbnormal right high cervical ICA consistent with dissection
CTA Final Impression
1. Rt. high cervical ICA dissection w/ limited antegrade blood flow beyond the 70% luminal stenosis The combination of antegrade flow plus pial collaterals revealed on cortical pial collateral gap.
2. Subtle reduction in the CT density within the venocapillary pool in the Rt. suprasylvian subcortical parietal white matter, likely representing end-of the-line ischemia in a posteriorly shifted watershed zone to the parietal white matter and the MCA-PCA watershed region. MR would be of value in determining whether there is actual acute post ischemic tissue in this region of the brain.
3. There is minimal post-ischemic dysautoregulation in the right superior division MCA.
4. Features of FMD in the left high ICA making FMD the likely the basis for the spontaneous right ICA dissection.