Case Notes
History
64 year old female presenting with acute onset Rt. hemiparesis, left gaze deviation and aphasia; no depressed level of consciousness; history of hypertension.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
Final CTA Impression1. There is a short segment proximal superior division MCA stenosis consistent with a recanalized artery rather than underlying fixed arterial stenosis. Since the stroke-zone includes the lenticulostriate and lateral orbitofrontal perfusion zone in addition to the superior division MCA, the initial thrombotic occlusion must have involved the M1/2 ICA segments.
2. Persistently significantly reduced CT density in the venocapillary pool is evident within the Lt. lateral orbitofrontal and anterior insular cortex with enough oligemia. Other affected areas (i.e the posterior insula and the Lt. lateral lenticulostriate perforator zones) improve their CT density toward normal; these could be in the ischemic penumbra.
3. There is no hemorrhagic conversion at this time.
4. There subtle loss of BBB in the distal Lt. MCA (M4) pial branches consistent with post-ischemic arteriopathy.