ABSTRACT NUMBER: ESOC2026A2232 BLOOD BLISTER ANEURYSMS PATIENT SERIES: A SINGLE CENTRE EXPERIENCE

Abstract Background and aims Blood blister aneurysms (BBA) are rare and small type of aneurysms, mostly located on dorsal wall of the internal carotid artery (ICA). They present significant treatment challenge because of high rupture risk due to their thin wall made only of adventitial layer and fibrous tissue, wide base and lack of proper aneurysm neck. Endovascular treatment with flow diverter (FD) stent is currently considered treatment of choice for BBA. Our aim is to present first Croatian series of BBA patients who were treated at our centre from 2015 until today and compare our results with similar case series found in literature. Methods We analysed demographical, clinical, and radiological features, as well as treatment timing, modalities, and outcomes of BBA patients in our cohort. Our results were compared with current literature data on BBA characteristics, treatment options and outcomes. Results We had fourteen patients with BBA in 10-year period. Average age was 49,6 years, ten of them were women. Nine patients had BBA on ICA. Twelve patients presented with subarachnoid haemorrhage and two of them were asymptomatic accidental findings. All symptomatic patients were treated in the first seven days. Nine patients were treated with FD, two were coiled and one underwent neurosurgical procedure. Treatment complications such as periprocedural ischemia or re-rupture were observed in five patients. Outcomes were satisfactory, with nine patients having modified Ranking score (mRS) 0-1 at discharge. Conclusions Literature review showed that characteristics and treatment outcomes of patients in this Croatian single-centre BBA cohort are consistent with similar BBA case series. Conflict of interest Ivana Karla Franić: nothing to disclose. Antonela Bazina Martinović: nothing to disclose. Danira Bažadona: nothing to disclose. Katarina Starčević: nothing to disclose. Ivan Perić: nothing to disclose. Nikola Blažević: nothing to disclose. David Ozretić: nothing to disclose. Jakov Kordić: nothing to disclose. Petar Ćurić: nothing to disclose. Zdravka Poljaković Skurić: nothing to disclose.