Posterior Inferior Cerebellar Artery Aneurysm Presenting With Severe Vertigo and Altered Sensorium.

Posterior inferior cerebellar artery (PICA) aneurysms are relatively uncommon among intracranial aneurysms and present unique challenges due to their complex anatomical origins. PICA aneurysms arise from the vertebral artery (VA), basilar artery, or anterior inferior cerebellar artery and can have complex anatomical sites and structures. A 31-year-old female known case of trigeminal neuralgia, currently asymptomatic for the same, experienced acute vertigo, headache, and altered sensorium. On the basis of the magnetic resonance imaging of the brain with angiography, she was diagnosed with a PICA aneurysm, necessitating immediate intervention. The patient subsequently underwent endovascular coiling of the aneurysm. The successful management of this unusual case emphasizes the significance of prompt diagnosis and early intervention in managing posterior inferior cerebellar artery aneurysms, leading to a favourable outcome. The patient is on regular follow-ups and has satisfactory progress.