Inducing and monitoring photothrombotic stroke in anesthetic neuroprotection-free mice using functional photoacoustic microscopy.

Significance: Preclinical ischemic stroke models frequently rely on inhalational anesthetics, which can alter cerebrovascular dynamics and confound ischemic outcomes. The specific impact of anesthesia at the microvascular level remains poorly defined, limiting the translational relevance of preclinical findings. Aim: We aim to utilize an optical resolution photoacoustic microscopy (OR-PAM) system for targeted photothrombosis (PT) induction and functional imaging and compare ischemic responses between awake and anesthetized mice to avoid anesthesia-induced confounding effects. Approach: We employed an OR-PAM system integrated with vascular stimulation capabilities, enabling PT induction in specific vessels and functional imaging of cortical brain regions. By combining with a head-restrained apparatus and photochemical thrombosis, we compared oxygen saturation ( Results: Before PT, awake mice exhibited narrower arteriovenous diameter and higher OEF compared with anesthetized mice induced by anesthesia. Following PT, awake mice displayed more severe acute Conclusions: Our findings address the critical gap of microvascular-level analysis in anesthesia-confounded stroke models. The proposed approach provides a reliable and reproducible tool for the precise induction of cerebral ischemia and dynamic monitoring of vascular changes.