External carotid artery stenting in patients with ipsilateral internal carotid artery occlusion: Peri-operative and 12-month follow-up.

OBJECTIVES This study aimed to evaluate the safety and clinical efficacy of external carotid artery (ECA) stenting in patients with ipsilateral internal carotid artery (ICA) occlusion. BACKGROUND In patients with ICA occlusion, severe ipsilateral ECA stenosis may exacerbate pre-existing cerebral ischemia and cognitive impairment. It remains unclear whether ECA stenting to normalize ECA collaterals to the cerebralis alleviates cerebral ischemia and improves cognitive function. METHODS From January 2008 to June 2019, we retrospectively collected clinical data of 36 consecutive patients with ipsilateral ICA occlusion who had undergone ECA stenting (mean age, 66.7 ± 8.3 years; males, n = 26 [72.2%]). Neurocognitive test results, including Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MOCA) tests, symptom assessment, and adverse events were recorded. RESULTS ECA stenting was successful in all 36 patients. Intra-operatively, six (16.7%) patients experienced hemodynamic depression during balloon dilation and recovered completely within 2 days. Within a 12-month follow-up period, two patients experienced a transient ischemic attack, one patient had a contralateral minor stroke, and 33 patients remained asymptomatic. No other adverse events occurred in the peri-operative or follow-up periods. Compared with baseline, significant MMSE (25.3 ± 1.3 vs. 23.6 ± 1.7; p < .05) and MOCA (24.1 ± 1.3 vs. 22.8 ± 1.7; p < .05) test score improvements were observed 3 months post-operatively and were maintained throughout follow-up. CONCLUSIONS ECA stenting may improve cerebral ischemia and cognitive function in patients with severe ECA stenosis and ipsilateral ICA occlusion; however, further research is required to support our findings.