P173 Indication, angiographic findings and complication following balloon test occlusion

<h3>Introduction</h3> Balloon test occlusion (BTO) is performed to evaluate ischaemic tolerance in patient who require vessel sacrifice. The indication for BTO include complex intracranial aneurysms, fistulae, and tumours of the skull base and neck. In recent years, the advances in skull base surgery and oncological treatment necessitated BTO. <h3>Aim of Study</h3> The purpose of this study was to evaluate the reliability of venous delay with clinical testing method and complication rates of angiography-based balloon test occlusion. <h3>Methods</h3> We performed a single-centre retrospective analysis of twenty-eight patients who underwent BTO from 2015 to February 2024. Venous delay and neurological status were analysed. <h3>Results</h3> The indication for procedure includes aneurysm (n=14), tumor (n=11), dissection (n=2) and caroticocavernous fistula (n=1). Six patients (21%) did not meet the BTO passing criteria while the remaining twenty-two patients (79%) passed the BTO. Transient symptoms arising from the BTO procedure included cephalgia (n=4), vertigo (n=2), hyposthenia (n=1), and bradyphrenia (n=1). The symptoms resolved immediately after balloon deflation. One patient had pseudoaneurysm of the left groin which was treated with 0.7 ml thrombin. One patient who clinically passed the BTO developed a transient thromboembolic stroke which was not related to BTO procedure but related to previous vessel occlusion and symptoms resolved. There was no post-surgical/procedural stroke following vessel sacrifice in patients who passed BTO. <h3>Conclusion</h3> Our single centre analysis shows that BTO is safe procedure with low rate of complication. The venous delay with clinical assessment method reliably predicts ischaemic tolerance. <h3>Disclosure of Interest</h3> no.