Stent match of pipeline embolization device: prediction of incomplete occlusion and in-stent stenosis by actual stent size after implantation.

The size of the Pipeline Embolization Device (PED) relative to the vessel is related to the therapeutic effect. However, the association between the stent-to-vessel matching status and treatment outcomes remains unclear. In this study, we aimed to evaluate this potential by measuring the dynamic changes in stent size during implantation. Participants who underwent PED implantation between September 2018 and September 2022 were reviewed. Coil-assisted embolization and multiple stents that could affect the measure accuracy were excluded. Three parameters were set to quantize the stent-matching degree: nominal match ratio (NMR), actual match ratio (AMR), and elongation ratio (ER). Study outcomes were incomplete occlusion and significant in-stent stenosis (ISS). The results were generated using multivariate logistic regression and restricted cubic spline (RCS) curves. A total of 388 patients were ultimately enrolled. Incomplete occlusion was observed in 22.4% and significant ISS in 5.2% at the last follow-up (11.63 ± 3.19 months). A larger distal AMR was significantly associated with incomplete occlusion (odds ratio [OR] = 12.733, 95% confidence interval [CI] = 3.678-44.082, p < 0.001) and significant ISS (OR = 43.469, 95% CI = 3.350-564.073, p = 0.004). The RCS curve indicated that the possibility of incomplete occlusion and significant ISS increased as the distal AMR exceeded 0.72 and 0.85, respectively. Neurointerventionalists should avoid pursuing over-expansion at the distal end when PED implantation. To match the vessel with significant lumen disparities and non-symmetrically tubular shapes, tapered FD and real-time software with automatic measure function were supposed to be developed in the future. TRIAL REGISTRATION: ClinicalTrials.gov (NCT06446778). Registered on May 22, 2024.