Influence of angioplasty and stenting on intracranial artery stenosis: preliminary results of high-resolution vessel wall imaging evaluation

To investigate whether the imaging changes on high-resolution vessel wall imaging (HR-VWI) in patients before and after percutaneous transluminal angioplasty and stenting (PTAS) contribute to predicting the clinical outcome. The study included 24 severe intracranial artery stenosis (SICAS) patients undergoing PTAS with Wingspan Stent between 2018 and 2020 and had a 1-year follow-up. Three HR-VWI sessions (preprocedural, early [within 24 h], and delayed postprocedural [134.7 ± 27.1 days]) in each subject were performed with 3-Tesla MRI. We evaluated periprocedural HR-VWI changes in patients with and without recurrent cerebral ischemic symptoms (RCIS) within 1-year follow-up. On CE-T1WI of the patients without RCIS, a significant decrease in enhanced area was observed on early postprocedural (0.04 ± 0.02 cm${}^2$, p = 0.001) and delayed postprocedural (0.04 ± 0.02 cm${}^2$; p = 0.001) HR-VWI compared to preprocedural (0.07 ± 0.02 cm${}^2$) HR-VWI. Patients with RCIS demonstrated no significant loss of enhanced area on CE-T1WI of early postprocedural HR-VWI (p = 0.180). Significant decreases in calibrated T1 signals were observed in both presence (1.77 ± 0.70 vs. 0.79 ± 0.52; p = 0.018) and absence (1.42 ± 0.62 vs. 0.83 ± 0.40; p = 0.001) of RCIS in early postprocedural HR-VWI. The preliminary results showed the presence of reduced contrast enhancement immediately after PTAS may indicate less recurrent stroke events within 1 year. Further studies are necessary to confirm the phenomena in a longer observation period. Early postprocedural high-resolution vessel imaging (HR-VWI) within 24 h can effectively predict a 1-year outcome following intracranial stenting. For stenotic lesions after stenting without reduced contrast enhancement on HR-VWI within 24 h may need closer clinical surveillance for potentially higher risk of stroke events within 1 year.