Photon-counting CT for Intracranial Stent Assessment

Intracranial atherosclerotic disease is an important cause of ischemic stroke, and intracranial stent implantation is increasingly used for patients with severe stenotic lesions. Evaluation of stent patency and detection of in-stent restenosis are essential during follow-up. Digital subtraction angiography (DSA) remains the reference standard for intracranial stent assessment; however, it is an invasive procedure associated with potential complications and radiation exposure. Conventional CT angiography may be limited by stent-related artifacts, including blooming artifact and beam-hardening effects, which can impair accurate evaluation of the stent lumen.

Inclusion Criteria: 1. Age ≥18 years; 2. Patients with previously implanted intracranial arterial stents; 3. Undergoing follow-up CTA examination; 4. Available imaging data for analysis. Exclusion Criteria: 1. Severe motion artifacts; 2. Poor contrast enhancement; 3. Incomplete clinical or imaging data.