Bilateral common carotid artery occlusion (BCCAO) is a widely used mouse model of global cerebral ischemia (GCI). However, marked inter-animal variability in ischemic severity, largely driven by anatomical heterogeneity of posterior communicating arteries (PcomAs), limits the reproducibility and comparability of this model. Although intraoperative real-time cerebral blood flow (CBF) monitoring offers a potential functional tool for predicting ischemic severity, validated threshold criteria for different monitoring platforms remain lacking. GCI was induced in male C57BL/6 J mice by 20 min of BCCAO. Cortical CBF was continuously monitored intraoperatively using either Laser Doppler Flowmetry (LDF) or Laser Speckle Contrast Imaging (LSCI). ROC analysis and K-means clustering were used to define optimal CBF reduction thresholds. Ischemic injury was evaluated by Nissl staining, H LSCI ≥80%). • PcomA anatomy is a major source of variability in the mouse BCCAO model. • Intraoperative LDF and LSCI identify low-collateral mice using CBF reduction thresholds of 85% and 80%. • Low-collateral mice show delayed hippocampal CA1 injury and memory impairment.
Zhang et al. (Fri,) studied this question.