Predictive Value of Baseline High-Resolution MRI Features for In-Stent Restenosis in Symptomatic Nonacute...

Among symptomatic nonacute intracranial atherosclerotic occlusion (ICAO), endovascular recanalization has shown potential efficacy and acceptable periprocedural complications. However, the long-term benefits of stent implantation could be diminished by in-stent restenosis (ISR). This study aimed to investigate the association between radiological features on preoperative high-resolution MRI (HR-MRI) and ISR.

We retrospectively reviewed 103 patients with symptomatic nonacute ICAO who underwent stenting between January 2018 to December 2024 at our institution. Patients' clinical-hematological parameters, HR-MRI features and procedural results were collected. Potential factors related to ISR were analyzed by univariate and multivariate analyses.

At a median 4.1-month imaging follow-up, this study observed a ISR rate of 29.1% (30/103) after stenting for nonacute ICAO. Based on multivariate analysis, plaque enhancement amplitude (≥ 1.43 vs. < 1.43, OR 3.960 (95% CI 1.279-12.265); P = 0.017), lumen collapsibility index (≥ 29.3% vs. < 29.3%, OR 5.124 (95% CI 1.703-15.413); P = 0.004), and degree of residual stenosis after recanalization (≥ 20.6% vs. < 20.6%, OR 5.311 (95% CI 1.832-15.400); P = 0.002) were independent ISR predictors. Furthermore, from 0 to 3 of these risk factors, the incidence of ISR increased significantly (6.5%, 17.1%, 61.9%, and 80.0%, respectively; P < 0.001).

In symptomatic nonacute ICAO patients, the baseline HR-MRI features were identified valuable for predicting ISR and individualized intervention of these imaging features may be beneficial to reduce restenosis risk. Further research with larger sample sizes and long-term follow-up is needed to confirm these findings.