An Unusual Case of a Thrombosed Giant Distal PICA Aneurysm Simulating a Large Cavernous Angioma

Giant partially thrombosed 4th ventricular posterior inferior cerebellar artery aneurysm; microsurgical management

“…Giant aneurysms, usually, present clinically as space-occupying lesions and differ from the presentation of the common and medium-sized aneurysms. [1,8] Thus, giant intracranial aneurysms may occasionally be mistaken for tumors. [1,9] Giant aneurysms typically appear on CT as rounded or oval-shaped masses with distinct outlines.…”

“…[1,8] Thus, giant intracranial aneurysms may occasionally be mistaken for tumors. [1,9] Giant aneurysms typically appear on CT as rounded or oval-shaped masses with distinct outlines. Calcifications are not uncommon findings, and the degree of contrast enhancement is strictly dependent on the amount of intra-aneurysmal thrombosis.…”

“…CT scans may not be sufficient to confirm the diagnosis of the nature of the lesion as reported by several authors because they could not differentiate between these lesions and tumors. [1] Angiography is performed in order to shed further light on the nature of the mass. Angiography is still the most important diagnostic tool because it reveals the true nature of the lesion, especially in patients like ours who do not show the signs and symptoms of subarachnoid bleeding and appear to have space-occupying lesions.…”

“…Vertebrobasilar system aneurysm account for 5-10% of all intracranial aneurysms. [1] Vertebral artery-posterior inferior cerebellar artery (VA-PICA) aneurysms constitute 0.5-3% of all intracranial aneurysms. [2] When aneurysm size exceeds 2.5 cm is called giant aneurysm.…”

“…Aneurysms of this size or larger are very rarely found in the vertebrobasilar system, and giant aneurysms of the PICA are also quite rare. [1] Surgery for these aneurysms is extremely challenging. Here, we report microsurgical management of a giant partially thrombosed 4 th ventricular PICA aneurysm.…”