| Literature DB >> 29799347 |
Daichi Nakagawa1, Kohsuke Kudo2, Olatilewa Awe1, Mario Zanaty1, Yasunori Nagahama1, Cameron Cushing3, Vincent Magnotta4, Minako Hayakawa4, Lauren Allan5, Jeremy Greenlee1, Issam A Awad6, Timothy Carroll7, James Torner8, Madhavan L Raghavan9, David M Hasan1.
Abstract
OBJECTSentinel headaches (SHs) associated with cerebral aneurysms (CAs) could be due to microbleeds, which are considered a sign that an aneurysm is unstable. Despite the prognostic importance of these microbleeds, they remain difficult to detect using routine imaging studies. The objective of this pilot study is to detect microbleeds associated with SH using a magnetic resonance imaging (MRI) quantitative susceptibility mapping (QSM) sequence and then evaluate the morphological characteristics of unstable aneurysms with microbleeds.METHODSTwenty CAs in 16 consecutive patients with an initial presentation of headache (HA) leading to a diagnosis of CA were analyzed. Headaches in 4 of the patients (two of whom had 2 aneurysms each) met the typical definition of SH, and the other 12 patients (two of whom also had 2 aneurysms each) all had migraine HA. All patients underwent imaging with the MRI-QSM sequence. Two independent MRI experts who were blinded to the patients' clinical history performed 3D graphical analysis to evaluate for potential microbleeds associated with these CAs. Computational flow and morphometric analyses were also performed to estimate wall shear and morphological variables.RESULTSIn the 4 patients with SH, MRI-QSM results were positive for 4 aneurysms, and hence these aneurysms were considered positive for non-heme ferric iron (microbleeds). The other 16 aneurysms were negative. Among aneurysm shape indices, the undulation index was significantly higher in the QSM-positive group than in the QSM-negative group. In addition, the spatial averaged wall shear magnitude was lower in the aneurysm wall in direct contact with microbleeds.CONCLUSIONSMRI-QSM allows for objective detection of microbleeds associated with SH and therefore identification of unstable CAs. CAs with slightly greater undulation indices are associated with positive MRI-QSM results and hence with microbleeds. Studies with larger populations are needed to confirm these preliminary findings.Entities:
Keywords: ACA = anterior cerebral artery; ACoA = anterior communicating artery; BA = basilar artery; CA = cerebral aneurysm; CFD = computational fluid dynamic; DICOM = Digital Imaging and Communications in Medicine; FLAIR = fluid attenuation inversion recovery; HA = headache; ICA = internal carotid artery; MCA = middle cerebral artery; MRA = magnetic resonance angiography; MRI = magnetic resonance imaging; PCoA = posterior communicating artery; QSM = quantitative susceptibility mapping; SH = sentinel headache; SWI = susceptibility-weighted imaging; TOF = time of flight; UI = undulation index; VMTKLab = Vascular Modeling Toolkit lab; WSS = wall shear stress; aSAH = aneurysmal subarachnoid hemorrhage; aneurysm; computed fluid dynamics; magnetic resonance imaging; microbleeds; ppm = parts per million; quantitative susceptibility mapping; sentinel headache; vascular disorders
Year: 2018 PMID： 29799347 PMCID： PMC6773513 DOI： 10.3171/2018.2.JNS1884
Source DB: PubMed Journal: J Neurosurg ISSN： 0022-3085 Impact factor: 5.115