Rare complication characterized by late-onset transient neurological symptoms without hyperperfusion after carotid artery stenting: A report of three cases

Abstract

<jats:p> We experienced a rare complication after carotid artery stenting (CAS) characterized by transient neurological symptoms with no evidence of distal emboli or hyperperfusion. Using neuroimaging, we investigated the pathogenesis of the complication that occurred after CAS in three patients who developed neurological symptoms over a period of ten hours after CAS and improved within two days. None of the three patients showed signs of fresh infarctions on diffusion-weighted imaging or hyperperfusion on single-photon emission computed tomography. However, high signal intensity was observed in the leptomeningeal zone of the cerebral hemisphere on the stent side in all three patients and in the leptomeningeal zone of the contralateral anterior cerebral artery territory in one patient. These areas were assessed using fluid-attenuated inversion recovery (FLAIR) magnetic resonance imaging without gadolinium administration. The high signal intensity in the leptomeningeal zone disappeared as the symptoms improved. Based on the transient nature of the neurological disorders and the normalization of FLAIR imaging findings in these patients, the pathogenesis of this complication might have been vasogenic edema due to vasoparalysis of the local vessels caused by the hemodynamic changes occurring after CAS. </jats:p>

HARMless: Transient Cortical and Sulcal Hyperintensity on Gadolinium-Enhanced FLAIR after Elective Endovascular Coiling of Intracranial Aneurysms

“…Most data arises from the neuro-radiology literature perhaps due to greater use of MR imaging following an angiographic procedure. [1][2][3][4][5][6][7] The FLAIR sequence is known to be particularly sensitive for the detection of various pathologic processes, including subarachnoid hemorrhage, meningitis, stroke, leptomeningeal carcinomatosis, and hyperoxygenation. 6,[8][9][10][11] FLAIR can be acquired before or after gadolinium administration.…”

“…25,26 Based on the limited evidence from the literature, there is speculation for a causative relationship between CSHF and ICM exposure. Complex pathophysiologic processes during endovascular procedures such as hypoperfusion, hypoxia, ischemia, and reperfusion injury or direct neurotoxicity of the contrast agent [1][2][3][4][5]19,21,22 can result in transient injuries to the BBB.…”

Transient neurological deficits mimicking left middle cerebral artery infarct after carotid artery stenting without associated imaging findings: A case report

“…After CAS, contrasting has been observed to increas as a result of the reversal of hemodynamics by flow recovery in the carotid system (4-6). As a rare complication of CAS, reversible neurological deficits and high signal intensities on the leptomeningeal zone on FLAIR imaging have observed (5,6). It has been considered that contrast enhancement in cerebral structures appeared because of temporary impairment in BBB result of non-ionic contrast agents (14).…”

“…Various complications have been reported after carotid artery stenting (CAS), including ischemic events, stent occlusion, hemorrhage, hyperperfusion syndrome, myocardial infarction, intestinal bleeding, contrast agent encephalopathy, delayed gadalonium enhancement of the leptomeningeal zone, and death (1)(2)(3)(4)(5)(6). Further, ischemic lesions and hyperperfusion syndrome are well-known complications of CAS, and new cerebral microembolic lesions detected via diffusionweighted imaging (DWI) are observed in almost all patients after CAS (7,8).…”