CT angiographic patterns predict carotid pseudo-occlusion in acute ischemic stroke

Area of Science:

• Neurology
• Radiology
• Vascular Surgery

Background:

• Distinguishing carotid pseudo-occlusion (PO) from true occlusion (TO) is critical for selecting patients for endovascular thrombectomy (EVT) in acute ischemic stroke (AIS).
• Accurate differentiation impacts the feasibility and success rates of EVT procedures.

Purpose of the Study:

• To identify computed tomography angiographic (CTA) patterns that differentiate PO from TO.
• To analyze the successful recanalization rates after EVT for both PO and TO.

Main Methods:

• Retrospective review of patients with acute ischemic stroke and proximal internal carotid artery (ICA) occlusion undergoing EVT (2014-2021).
• Classification of CTA patterns (beak, dome, flat) and correlation with digital subtraction angiography (DSA) findings for PO/TO.
• Analysis of successful recanalization rates in PO versus TO groups.

Main Results:

• 16 patients had ICA PO and 8 had TO. CTA beak patterns were significantly more frequent in PO (87.5% vs. 25%, P=0.005).
• CTA flat patterns were more common in TO (50% vs. 12%, P=0.005). Gradual contrast decline on CTA was specific to PO (85.7% vs. 0%, P=0.05).
• Successful recanalization rates did not differ significantly between PO (81.25%) and TO (62.5%) groups (P=0.362).

Conclusions:

• CTA findings, specifically beak patterns and gradual contrast decline at the proximal ICA, are indicative of carotid pseudo-occlusion.
• Identifying PO via CTA aids in planning intervention strategies and patient prognostication for acute ischemic stroke.
• CTA is a valuable tool for differentiating carotid occlusion types, guiding EVT decisions.