Hemodynamic features of an intracranial aneurysm rupture predicted by perianeurysmal edema: A case report

Abstract

Background: Perianeurysmal edema (PAE) has been suggested as an indicator of potential aneurysm rupture; however, the hemodynamic features of these aneurysms are still unknown. A computational fluid dynamic (CFD) analysis was performed to evaluate the hemodynamic features of a very rare case of a ruptured middle cerebral artery (MCA) aneurysm with PAE. Case Description: A 65-year-old woman presented with disturbed consciousness. A subarachnoid hemorrhage due to an azygos anterior cerebral artery (ACA) aneurysm rupture was suspected. An unruptured MCA aneurysm with PAE was identified in the left temporal lobe. Although the ACA aneurysm was clipped to prevent re-bleeding, the MCA aneurysm subsequently ruptured 6 days later. Clipping of the MCA aneurysm was performed, and hemosiderin deposits suggestive of sentinel bleeding were found on the surface of the aneurysm dome. CFD analysis revealed unstable hemodynamic stress at the expanded bleb area after rupture, localized to the rupture site. Moreover, this analysis revealed flow impingement with pressure elevation and low wall shear stress, which indicated increased inflammation and aneurysm wall thinning that likely led to rupture. Conclusion: Hemosiderin deposits at the aneurysm wall and PAE indicates leakage from a cerebral aneurysm. Hemodynamic stress at the aneurysm may promote an inflammatory response and lead to wall weakening accompanied by PAE. Based on our findings, we recommend that surgical intervention should be considered as the first line of treatment for such aneurysms to prevent rupture.

Case report: Unruptured small middle cerebral artery aneurysm with perianeurysmal edema

“…Hemosiderin deposits can be considered an indirect sign of minor leakage, which can be a predictive sign of impending aneurysm rupture ( 1 ). Contrary to our case study, previous reported cases have observed hemosiderin deposits around the aneurysm and brain parenchyma during the operation ( 1 , 6 ). Lack of hemosiderin deposits is a crucial finding of our case compared with previous cases because it clearly indicates that PAE can occur without any minor leakage.…”

“…also analyzed 69 cases of giant intracranial aneurysms (>25 mm) of which 33.3% developed PAE ( 3 ). In contrast, there have only been five cases of PAE in unruptured and/or untreated aneurysms ( 1 , 6 – 8 ). Among them, four cases experienced aneurysm rupture immediately after the manifestation of PAE, whereas in one case PAE was speculated due to a minor leakage.…”