Early Postprocedural Susceptibility-Weighted Imaging and Vessel-Wall Imaging For Prediction of Complications After Flow-Diversion Treatment of Intracranial Aneurysms

Susceptibility-weighted imaging (SWI) and vessel wall imaging (VWI) are among the most recent magnetic resonance (MR) techniques used to evaluate the cerebral vascular system (1,2). SWI; In addition to detecting the damage caused by many cerebrovascular pathologies at the microvascular level more sensitively than other imaging methods, it is the only MR sequence that can be used to differentiate blood-iron-calcification. It is the most sensitive MR sequence for iron accumulation and calcification. In addition to cerebrovascular diseases, it can be used in neurodegenerative diseases, especially parkinsonism, in the evaluation of tumoral - infective processes that can go with calcification (3). Similarly, VWI; It is used with increasing frequency in current practice in the diagnosis of pathologies affecting the vessel wall such as dissection, atherosclerotic change, inflammation and vasculitic involvement that cannot be clearly distinguished by normal vessel imaging methods (4). For both SWI and VWI, an MR device infrastructure with at least 3T magnetic field strength is required (2,5). Both techniques have limited diagnostic capabilities at magnetic field strengths up to 1.5T.

In studies conducted with VWI, it is stated that staining detected with VWI on the aneurysm wall may have predictive properties in terms of rupture (6,7). In addition, microhemorrhages detected by SWI imaging have been reported to transform into large parenchymal hemorrhages due to perfusion changes (8). Distant bleeding occurs due to perfusion change in some of the aneurysm cases that receive flow-directing therapy (9). In addition, rupture of the aneurysm may occur in some of the cases in which this treatment is applied, and stent stenocclusion may occur in some (10-11).

In the light of the above information, we aimed to evaluate the relationship between microhemorrhages, which may be a precursor of large parenchymal hemorrhages, staining of the aneurysm wall that may reflect the potential for rupture with VWI, and vessel wall staining or hematoma, which may reflect the risk of stenocclusion, with SWI examination to be performed on a 3T MR device in cases of intracranial aneurysms that were treated with flow-guided therapy, and complications developing after treatment.

References:

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