A Clinical Study on the Improvement of Cognitive Function in Symptomatic Non-Acute Internal Carotid Artery Occlusion Patients with Hasan Type A and B

Symptomatic non-acute internal carotid artery occlusion (NA-ICAO), particularly Hasan type A/B, is characterized by persistent cerebral hypoperfusion that may lead to neurological and cognitive impairment. Endovascular recanalization therapy (EVT) aims to restore cerebral blood flow and improve functional outcomes in patients with these conditions. A total of 66 patients with symptomatic NA-ICAO admitted between June 2022 and October 2023 were randomly assigned to an EVT group (n = 32) or a conservative medical therapy group (n = 34). Neurological and cognitive functions were evaluated before treatment and at 3 and 12 months after treatment using standardized scales, including the modified Rankin Scale (mRS), National Institutes of Health Stroke Scale (NIHSS), Mini-Mental State Examination (MMSE), and Montreal Cognitive Assessment (MoCA). Recanalization was successfully achieved in all 32 patients, with 9 cases reaching TICI grade 2b and 23 cases reaching TICI grade 3. Among 32 patients undergoing EVT, 12 (37.5%) experienced perioperative adverse events, including 2 (6.25%) serious events. At 3 months, the mRS score was significantly lower in the EVT group than in controls. At 12 months, the EVT group showed significantly greater improvements in MMSE, mRS, and MoCA scores, with the largest effect size observed for MoCA (Cohen's d = 0.82). Domain-specific analysis revealed significant improvement in language ability. EVT may offer potential clinical benefits for selected patients with chronic carotid occlusion; however, larger multicenter studies are warranted to confirm its long-term efficacy and safety.