%0 Journal Article %A Siming Gui %A Xiheng Chen %A Dachao Wei %A Dingwei Deng %A Wei You %A Xiangyu Meng %A Jian Lv %A Junqiang Feng %A Yudi Tang %A Shu Yang %A Ting Chen %A Peng Liu %A Huijian Ge %A Hengwei Jin %A Xinke Liu %A Yuhua Jiang %A Wei Feng %A Youxiang LI %T Long-term outcomes and dynamic changes of in-stent stenosis after Pipeline embolization device treatment of intracranial aneurysms %D 2023 %R 10.1136/jnis-2022-019680 %J Journal of NeuroInterventional Surgery %P jnis-2022-019680 %X Background Flow diverters have revolutionized the treatment of intracranial aneurysms. However, the delayed complications associated with flow diverter use are unknown.Objective To evaluate the incidence, severity, clinical outcomes, risk factors, and dynamic changes associated with in-stent stenosis (ISS) after treatment with a Pipeline embolization device (PED).Methods Patients who underwent PED treatment between 2015 and 2020 were enrolled. The angiographic, clinical, and follow-up data of 459 patients were independently reviewed by four neuroradiologists to identify ISS. Binary logistic regression was conducted to determine ISS risk factors, and an ISS–time curve was established to demonstrate dynamic changes in ISS after PED implantation.Results Of the 459 treated patients, 69 (15.0%) developed ISS. At follow-up, nine patients (2.0%) with ISS demonstrated reversal, while 18 (3.9%) developed parental artery occlusion. A total of 380 patients (82.8%) achieved complete aneurysm occlusion (O’Kelly–Marotta grade D). Patients with posterior-circulation aneurysm (OR=2.895, 95% CI (1.732 to 4.838; P<0.001) or balloon angioplasty (OR=1.992, 95% CI 1.162 to 3.414; P=0.037) were more likely to develop ISS. Patients aged >54 years (OR=0.464, 95% CI 0.274 to 0.785; P=0.006) or with a body mass index of >28 kg/m2 (OR=0.427, 95% CI 0.184 to 0.991; P=0.026) had a lower ISS risk. Intimal hyperplasia initiated by PED placement peaked within 1 year after the procedure, rarely progressed after 12 months, and tended to reverse within 24 months.Conclusions ISS is a common, benign, and self-limiting complication of PED implantation in the Chinese population.Data are available upon reasonable request. The authors agree to share data upon reasonable request. Any data from this study are available by contacting the corresponding author. %U https://jnis.bmj.com/content/neurintsurg/early/2023/01/22/jnis-2022-019680.full.pdf