A rare case of a completely thrombosed bilobed giant intracranial aneurysm of the anterior cerebral artery with spontaneous parent vessel thrombosis: case report

Abstract

BackgroundA huge spherical intracranial mass can sometimes be misdiagnosed, due to the lack of typical radiographic features. Thrombosed giant intracranial aneurysms (GIAs) are an uncommon but still a possible differential diagnosis that must be kept in mind to guarantee the best surgical approach and resection of the lesion. We describe an extremely rare case of a huge bifrontal mass mimicking a cystic echinococcosis, in which the surgery unveiled a completely thrombosed GIA of the left anterior cerebral artery (ACA).Case presentationA 61-year-old patient complained about intermittent weakness of the right leg, mild holocephalic headache, beginning cognitive deficits and lethargy. Magnetic resonance imaging (MRI) showed a huge partially calcified and bilobed frontal mass with peripheral edema. Based on a time-resolved angiography with interleaved Stochastic trajectories MRI (TWIST-MRI), a vascular origin of the lesion was considered unlikely. Therefore, the surgery was performed under the suspicion of a cystic echinococcosis but revealed a bilobed GIA of the left ACA with a parent vessel thrombosis. Although only a limited left frontal craniotomy was performed, a proximal control of the parent vessel could be ensured, and the aneurysm was successfully clipped. The patient showed postoperatively no new neurological deficits.ConclusionsCompletely thrombosed GIAs with parent vessel thrombosis are rare lesions that might be misdiagnosed if typical radiographic features are missing. Thus, in case of an intracranial spherical mass with signs of intralesional hemorrhage and mural calcifications, presence of a completely thrombosed GIA should be considered as a possible differential diagnosis.

Symptomatic Cavernous Internal Carotid Artery Aneurysm Complicated by Simultaneous Rapid Growth of the Intra-aneurysmal and Parent Artery Thromboses

“…Localized stretching, compression, and distortion of the ICA could explain the occurrence of this pathological condition in cavernous ICA aneurysms, which may be due to the presence of dural folds and bony structures at this location. 10) The possibility of distal embolic occlusion secondary to migration of intra-aneurysmal thrombus (aneurysm-to-distal arteries emboli) has also been previously described. 9) According to the literature, about 5–8% of thrombus-containing giant intracranial aneurysms were associated with distal thrombo-embolism.…”

“… 5 , 9) Hemodynamic stress on the aneurysmal wall with subsequent endothelial damage has been described as the main cause of this phenomenon. 5 , 10) The key predisposing factors are known to be an increased dome-neck ratio, long-standing aneurysm, and blood hypercoagulability. 5) Simultaneous thromboses in the aneurysm and its parent artery is a rare clinical condition, and the exact mechanism behind this complication remains unclear.…”

“… 5) Simultaneous thromboses in the aneurysm and its parent artery is a rare clinical condition, and the exact mechanism behind this complication remains unclear. 5 , 10 , 11) Whittle et al 12) described two possible mechanisms: first, the direct distortion and compression of the parent artery by the aneurysm, and second, the retrograde development of the thrombus originating from the aneurysm. Localized stretching, compression, and distortion of the ICA could explain the occurrence of this pathological condition in cavernous ICA aneurysms, which may be due to the presence of dural folds and bony structures at this location.…”

Distal middle cerebral artery dissection with concurrent completely thrombosed aneurysm manifesting as cerebral ischemia. A case report and review of the literature

“…Magnetic Resonance may demonstrate a lumen with heterogeneous signal on T1- and T2-weighted images, “onion skin” appearance on noncontrast T1 weighted images, a flow void sign, thrombus non-enhancement or rim enhancement along the thrombus margin [12 , 13] . Eleven similar cases have been reported in the literature ( Table 1 ) and were commonly mistaken for neoplasms on initial imaging work up with the final diagnosis commonly established during surgery [14] , [15] , [16] , [17] , [18] , [19] , [20] , [21] , [22] , [23] , [24] . Only 3 aneurysms affected the middle cerebral artery.…”

PaCO2-management in the neuro-critical care of patients with subarachnoid hemorrhage

“…Further conservative aSAH management was performed according to the latest guidelines 7 , 8 and included oral nimodipine and euvolemia maintenance for 3 weeks. Conservative and invasive treatment of cerebral vasospasm after aSAH has been described in detail elsewhere 12 . The Bleeding source was confirmed using digital subtraction and/or computed tomography (CT)-angiography.…”