Evaluation of carotid angioplasty and stenting for radiation-induced carotid stenosis.

BACKGROUND AND PURPOSE: We aimed to evaluate the procedural safety, clinical, and angiographic outcome of carotid angioplasty and stenting for high-grade (≥70%) radiation-induced carotid stenosis (RIS) using atherosclerotic stenosis (AS) as a control. METHODS: In this 6-year prospective nonrandomized study, we compared the carotid angioplasty and stenting outcome of 65 consecutive patients (84 vessels) with RIS with that of a control group of 129 consecutive patients (150 vessels) with AS. Study end points were 30-day periprocedural stroke or death, ipsilateral ischemic stroke, technical success, procedural characteristics, instent restenosis (ISR; ≥50%) and symptomatic ISR. RESULTS: The median follow-up was 47.3 months (95% confidence interval, 26.9-61.6). Imaging assessment was available in 74 vessels (RIS) and 120 vessels (AS) in 2 years. Comparing RIS group with AS group, the rates of periprocedural stroke or death were 1.5% (1/65) versus 1.6% (2/129; P=1); ipsilateral ischemic stroke rates were 4.6% (3/65) versus 4.7% (6/129; P=1); the annual risks of ipsilateral ischemic stroke were 1.2% (3 patient/254.7 patient year) versus 1.2% (6 patient/494.2 patient year; P=0.89); technical success rates were both 100%. Stenting of common carotid artery and the use of multiple stents was more common in the RIS group (P=0 in both cases); ISR rates were 25.7% (19/74) versus 4.2% (5/120; P<0.001); symptomatic ISR rates were 6.8% (5/74) versus 0.8% (1/120; P=0.031). CONCLUSIONS: The safety, effectiveness, and technical difficulty of carotid angioplasty and stenting for RIS are comparable with that for AS although it is associated with a higher rate of ISR. CLINICAL TRIAL REGISTRATION: This trial was not registered as enrollment started in 2006.

Angiographic features, collaterals, and infarct topography of symptomatic occlusive radiation vasculopathy: a case-referent study.

BACKGROUND AND PURPOSE: Occlusive radiation vasculopathy (ORV) predisposes head-and-neck cancer survivors to ischemic strokes. METHODS: We analyzed the digital subtraction angiography acquired in 96 patients who had first-ever transient ischemic attack or ischemic strokes attributed to ORV. Another age-matched 115 patients who had no radiotherapy but symptomatic high-grade (>70%) carotid stenoses were enrolled as referent subjects. Digital subtraction angiography was performed within 2 months from stroke onset and delineated carotid and vertebrobasilar circulations from aortic arch up to intracranial branches. Two reviewers blinded to group assignment recorded all vascular lesions, collateral status, and infarct pattern. RESULTS: ORV patients had less atherosclerotic risk factors at presentation. In referent patients, high-grade stenoses were mostly focal at the proximal internal carotid artery. In contrast, high-grade ORV lesions diffusely involved the common carotid artery and internal carotid artery and were more frequently bilateral (54% versus 22%), tandem (23% versus 10%), associated with complete occlusion in one or both carotid arteries (30% versus 9%), vertebral artery (VA) steno-occlusions (28% versus 16%), and external carotid artery stenosis (19% versus 5%) (all P<0.05). With comparable rates of vascular anomaly, ORV patients showed more established collateral circulations through leptomeningeal arteries, anterior communicating artery, posterior communicating artery, suboccipital/costocervical artery, and retrograde flow in ophthalmic artery. In terms of infarct topography, the frequencies of cortical or subcortical watershed infarcts were similar in both groups. CONCLUSIONS: ORV angiographic features and corresponding collaterals are distinct from atherosclerotic patterns at initial stroke presentation. Clinical decompensation, despite more extensive collateralization, may precipitate stroke in ORV.