Differential patterns of territory-specific CT perfusion reflecting hemodynamic status before and after revascularization in non-acute MCA occlusion

Medial and lateral lenticulostriate artery(LSA) territories may exhibit different hemodynamic vulnerability in symptomatic non-acute MCAO (>2 weeks after onset). This study evaluated territory-specific CT perfusion (CTP) changes before and after endovascular recanalization. Eighteen patients with symptomatic non-acute MCAO who underwent successful endovascular recanalization and perioperative CTP were retrospectively analyzed.Cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT), and time to peak (TTP) were measured in medial and lateral LSA territories on the affected/recanalized side and contralateral reference side. Relative indices were calculated as rCBV, rCBF, rMTT, and rTTP. Prespecified paired comparisons were performed. Before recanalization, the lateral territory showed more severe hypoperfusion than the medial territory, with lower CBV and CBF and longer MTT and TTP. The medial territory showed preserved CBV despite reduced CBF and delayed transit. After recanalization, the lateral territory showed increased rCBF and shortened rMTT/rTTP. The medial territory also showed improved flow and transit, while rCBV decreased, consistent with resolution of compensatory vasodilation. Medial and lateral LSA territories show distinct CTP profiles in symptomatic non-acute MCAO. Territory-based CTP analysis may clarify deep perforator hemodynamics and treatment response after recanalization. Not applicable.