Progressive perianeurysmal edema induced after endovascular coil embolization

Abstract

The authors report three cases of progressive vasogenic brain edema surrounding a cerebral aneurysm after endovascular coil embolization. In all three cases embolization was incomplete due to the aneurysms' large sizes and wide necks. Follow-up magnetic resonance imaging revealed de novo vasogenic brain edema surrounding the aneurysms 3 to 6 months after the initial treatment. The edema progressed in parallel with regrowth of the aneurysms. All three aneurysms were deep in the brain parenchyma and showed intramural enhancement, suggesting hemorrhage or inflammation. Each patient underwent a second embolization for the aneurysm regrowth, which resulted in improvement of the edema. Based on the findings in these cases and review of the literature, it is suggested that incomplete occlusion of larger aneurysms that are deep within the brain may lead to a disorganized intraluminal thrombosis, aneurysm pulsing, and intramural hemorrhage or inflammation, all of which are associated with brain edema following aneurysm recanalization and regrowth. It should be kept in mind that incomplete embolization of larger aneurysms may cause such malignant change and that this complication may occur after endovascular treatment.

Long-term follow-up of endovascular coil embolization for cerebral aneurysms using three-dimensional time-of-flight magnetic resonance angiography

“…We have so far reported three cases of perianeurysmal edema after coil embolization 21 . Five cases with perianeurysmal edema were identified totally, and all of them recurred in our series.…”

Symptomatic Perianeurysmal Edema Following Bare Platinum Embolization of a Small Unruptured Cerebral Aneurysm

“…These include intraluminal thrombosis, aneurysm pulsatility, intramural hemorrhage, wall inflammation, and cytokine release. 2,12 Some patients respond to steroid therapy, a feature that supports an inflammatory etiology, as does the observation of increased white cells and protein in the CSF of certain patients 4 ; however, complete symptomatic improvement is not always guaranteed. 3,4,9,13 Postmortem histologic studies have revealed an inflammatory infiltrate within the wall of embolized aneurysms, 16 and this is likely to have a correlate in the form of wall enhancement on gadolinium-enhanced MR imaging studies.…”

“…7 Following coil embolization, certain patients have developed de novo edema, whereas treatment has also been associated with a reduction or resolution of the brain edema in others. 12 The mechanism by which edema develops around an aneurysm is unclear, and various interrelated factors have been postulated. These include intraluminal thrombosis, aneurysm pulsatility, intramural hemorrhage, wall inflammation, and cytokine release.…”

“…These include headache, lethargy, meningism, blindness, confusion, and impaired cognition. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15] MR imaging has been performed in some instances and has variably demonstrated hydrocephalus, aneurysm enhancement, perianeurysmal edema, and perianeurysmal enhancement.…”

Endoscopic Third Ventriculostomy for Obstructive Hydrocephalus Caused by a Large Upper Basilar Artery Aneurysm After Coil Embolization

“…6,9) We directly observed a pulsating upper BA aneurysm located near the right mamillary body with a reddish color change using the videoscope. We thought the reddish color change of the ventricle wall was a result of the aneurysm pulsation and coil compression causing inflammation.…”