The efficacy of intentional compressed placement of flow diverter stent for improvement of operative results against internal carotid artery and posterior communicating artery bifurcation aneurysms: patient series.

backgroundInternal carotid artery and posterior communicating artery bifurcation aneurysms (ICPC ANs) have a relatively high recurrence rate. The authors report 8 cases in which good results without coil compaction were confirmed during the follow-up period by using a small number of coils followed by flow diverter (FD) stent placement. OBSERVATIONS: The mean maximum aneurysm diameter in the 8 cases was 8.7 ± 4.1 mm, the mean number of coils used was 1.5 ± 0.9, and the average volume embolization rate was 14.7% ± 9%. In 6 of the 8 cases, no coil compaction was observed 1 year after treatment compared with the end of procedure, and in 2 cases, the coil shape changed in a way that preserved the origin of the fetal-type posterior communicating artery, and no compaction was observed within the aneurysm. Complete embolization was achieved in 7 of 8 cases; 1 case, in which direct oral anticoagulant was used, had a neck remnant, but no aneurysm enlargement or significant compaction was observed. LESSONS: FD placement with intentional stent compression may be effective in the treatment of ICPC AN. When using a small number of coils are used in combination, it is possible to confirm the absence of coil compaction, which may lead to visualization of good results. https://thejns.org/doi/10.3171/CASE25430.