P063 Subarachnoid hemorrhage: a neurovascular anatomy perspective on a particular case

<h3>Introduction</h3> We present the case of a 47-year-old woman with subarachnoid hemorrhage due to multiple pial AVMs,highlighting the intricate neurovascular anatomy that interventional neuroradiologists should be mindful of in such cases. <h3>Case Description</h3> The 47-year-old female presented with sudden headache, photophobia, nausea, and vomiting. CT imaging revealed perimesencephalic, non-traumatic subarachnoid hemorrhage predominantly located on the left side. Additionally, areas of SAH were observed at the levels of the Sylvian fissures and interhemispheric fissure, with minimal involvement at the levels of the 3rd and 4th ventricles. CTA did not reveal any aneurysm dilation or rupture. Notably, several tortuous branches were identified at the level of the PICA,raising suspicion of a pial AVF. Angiography was subsequently performed for further evaluation. <h3>Results</h3> Angiography revealed several variations in the neurovascular anatomy. Originating from the Aortic Arch, a left Vertebral Artery was observed medial to the Left Subclavian origin. On the left side, the dominant PcommA with a hypoplastic P1 segment. On the right side, the MCA exhibited early M1 bifurcation, a phenomenon seen in approximately 2.5% of the population per Huber et al(1982). During the assessment of the AVF, two PICAs were observed emerging from a common trunk. The superior branch exhibited a more tortuous path, supplying the AVF, and anastomosing with the posterior spinal artery. The inferior branch displayed the characteristic trajectory of a PICA and a small microaneurysm was identified here. Follow-up angiography was scheduled, and the patient was placed under observation. <h3>Disclosure of Interest</h3> no.