RT Journal Article SR Electronic T1 P055 Mystic rupter of the large anterior comunicate aneurysm 1 year after the treatment with low-profile flow diverter stent, with no evidence of the sacc perfusion on the follow up imaging JF Journal of NeuroInterventional Surgery JO J NeuroIntervent Surg FD BMJ Publishing Group Ltd. SP A57 OP A58 DO 10.1136/jnis-2024-ESMINT.92 VO 16 IS Suppl 2 A1 Gavrilovic, Vladimir A1 Dapoto, Annarita A1 Sponza, Massimo YR 2024 UL http://jnis.bmj.com/content/16/Suppl_2/A57.abstract AB Introduction Wide neck aneurysm of the anterior communicating artery frequently involving A1-2 angle are challenging cases for the surgery and endovascular treatment (EVT). The availability of low-profile flow-diverter stents nowadays enables EVT of intracranial aneurysms beyond the circle of Wills. Case Description 67 years old male patient (Pt.) with occasional large asymptomatic anterior communicant aneurysm, mostly thrombosed, was candidate for EVT with low-profile flow diverter stent under double antiplatelet therapy preparation. Although the presence of advanced atherosclerotic disease the stent was easily deployed from A2 to A1 ipsilateral segment with complete aneurysm exclusion and minimal contrast media stagnation in it. After the procedure, Heubner artery occlusion was observed, in correlation with complex clinical situation, while ischemia of head of the caudate nucleus on CT imaging was diagnosed.Results Good clinical improvement was osberved on the follow up (FU). Treated aneurysm was occluded on 1-month CT imaging, with a minimal increase of the diameter 19mm versus 14mm before the treatment. No contrast impregnation of aneurysm wall neither aneurysm sacc perfusion was observed on 3-month magnetic resonance with contrast media FU. 12-months after the treatment Pt. was hospitalized for subarachnoid hemorrhage due to aneurysm rupture with no evidence of sacc perfusion on the angiography control that was mandatory before the surgery treatment.