Spatial and Temporal Assessment of Cerebral Blood Flow in a Novel Piglet Model of Neonatal Arterial Ischemic Stroke.

Neonatal arterial ischemic stroke (NAIS) is associated with considerable pediatric morbidity and mortality but lacks effective treatment options compared to adult ischemic stroke, highlighting the need for clinically relevant translational models. This study aimed to develop a novel middle cerebral artery occlusion (MCAO) model in neonatal piglets with high clinical relevance and the opportunity for long-term survival. Piglets were randomly assigned to undergo either MCAO (n = 8) or sham surgery (n = 6). MCAO was achieved by occluding MCAs using 7 mm aneurysm clips via craniotomy. Laser speckle contrast imaging was used to measure changes in relative cerebral blood flow (rCBF) in three cortical regions (anterior cerebral artery territory, penumbra, and ischemic core). Open field testing was performed in a subset of piglets at baseline, at 24 h post-MCAO-induction (MCAOi), and at 48 h post-MCAOi. 2,3,5-triphenyl tetrazolium chloride (TTC) staining was used to identify infarcts at 48 h post-MCAOi. By 10 min post-MCAOi, rCBF had increased approximately 22.4% in the ischemic core compared to immediately post-MCAOi (p < 0.05), with the area of the core as a percentage of the ipsilateral hemisphere decreasing by approximately 38%. Further, piglets in the MCAO group showed increased ipsiversive circling at 24 h and 48 h post-MCAOi compared to pre-surgery as well as higher infarct volumes compared to piglets in the sham group (31.6 ± 17.0%, p < 0.01). Overall, our model creates a reproducible infarct with consistent neuromotor deficits, real-time assessment of rCBF dynamics, and long-term survival, thus offering insights that may inform the development of novel therapies and improve outcomes for patients affected by NAIS.