The area between 2 or more arterial supplies will get the worst perfusion if blood pressure falls.
- Watershed infarcts comprise ~10% of all ischaemic strokes
- Infarcts are localized to border zones between major vascular territories
- Can be internal borderzone (IBZ) or cortical borderzone (CBZ) infarcts
Cortical Border Zone infarct
- Infarcts at junctions of the distal branches of the ACA, MCA and PCA territories.
- Often unilateral related to small embolic cortical infarcts.
- Often a narrow wedge between the territories either frontal or parieto-occipital
- Infarcts at junctions of the distal branches of the large vessels and deep perforating arteries (lenticulostriate, artery of Heubner, anterior choroidal artery).
- More associated with hypotension, severe stenosis or occlusion of ICA/MCA.
- Infarcts arranged circumferentially possibly symmetrically.
- Severe hypertension with rapid reduction
- Perioperative BP variation
- Episode of Shock
- Severe carotid disease
- As for cortical/subcortical structures involved
- FBC, U&E, LFTs, ECG, Troponin, Lactate
- Carotid duplex or MRA, Echocardiogram
- Ensure adequate cerebral perfusion
- Stroke rehabilitation
- See Ischaemic stroke