Intracranial pseudoaneurysm due to rupture of a saccular aneurysm mimicking a large partially thrombosed aneurysm (?ghost aneurysm?)

Abstract

Intracranial pseudoaneurysm formation due to ruptured non-traumatic saccular aneurysm is extremely rare. We experienced two cases of large pseudoaneurysm formation due to rupture of a saccular aneurysm. The neuroradiological ghost-like appearance of the aneurysms led to misdiagnoses as large partially thrombosed aneurysm. Two cases of large intracranial pseudoaneurysm formation due to rupture of a saccular aneurysm occurred in a 77-year-old comatose woman with an aneurysm on the anterior wall of the internal carotid artery and a 73-year-old comatose woman with an anterior cerebral artery (azygos) aneurysm. Both patients suffered subarachnoid hemorrhage associated with intracerebral and intraventricular hematomas. Angiography showed peculiar "ghost-like" appearance of the aneurysm including delayed filling, changing shape, retention of the contrast material after the venous phase, and unclear location of neck. Neck clipping surgeries were performed, but were difficult because of the preoperative misdiagnosis as large partially thrombosed aneurysm. The entity of "ghost aneurysm" caused by rupture of a saccular aneurysm should be considered in the clinical diagnosis.

“Real time” Angiographic Evidence of “Pseudoaneurysm” Formation After Aneurysm Rebleeding

“…Pseudoaneurysms may occur at the rupture site of true aneurysms as consequence of aneurysm's wall tear and reorganization of the clot present on the rupture site [1]. Characteristically, true aneurysms associated to pseudoaneurysm formation may appear irregularly shaped, as in our case, suggesting the presence of a thrombus in the site of rupture [2,3]. As shown in our case, pseudoaneurysms appear angiographically with delayed and incomplete opacification and delayed washout of contrast medium from their cavities [3,4].…”

Acute phase endovascular intervention on a pseudoaneurysm formed due to rupture of an anterior communicating artery aneurysm

“…Intracranial pseudoaneurysm formation due to a ruptured non-traumatic saccular aneurysm is an extremely rare condition,1–3 with characteristic angiographic findings referred to as ‘ghost aneurysm’ or ‘snowman’s head’ 1 2. At present, no detailed information about the treatment of this condition is available.…”

Provocative tests and parent artery occlusion in the endovascular treatment of distal middle cerebral artery pseudoaneurysms

“…1,2 In this series, there were some angiographic clues to foresee or atleast suspect the existence of PA of the dMCA. Once the diagnosis of intracranial PA is confirmed, definitive treatment should be performed.…”

“…1,2 To provide information for clinical diagnosis and therapy of this disease, we analysed 13 patients with PA of the dMCA who underwent endovascular treatment.…”