Artifact quantification and tractography from 3T MRI after placement of aneurysm clips in subarachnoid hemorrhage patients

BMC Medical Imaging

Research Article

Shuichi Suzuki¹  Fiona Rohlffs²  Timothy M Ellmore²  Faraz Khursheed²  Dong H Kim² 

[1] Department of Diagnostic and Interventional Imaging, The University of Texas Medical School at Houston, 6431 Fannin St., 77030, Houston, TX, USA;Neurointerventional/Neuro Endovascular, Radiological Sciences, University of California, Irvine, Mail Code: 5005, 101 The City Drive South, Rt. 140, South Bldg. 56, 92868, Orange, CA, USA;The Vivian L. Smith Department of Neurosurgery and Mischer Neuroscience Institute, The University of Texas Medical School at Houston, 6431 Fannin St., 77030, Houston, TX, USA;

关键词: artifact;    BOLD-fMRI;    diffusion-weighted imaging;    inferior fronto-occipital fasciculus;    intracranial aneurysm clip;    magnetic resonance imaging;    subarachnoid hemorrhage;    titanium alloy;    uncinate fasciculus;   

DOI  :  10.1186/1471-2342-11-19

 received in 2011-05-25, accepted in 2011-10-04,  发布年份 2011

来源: Springer

【 摘 要 】

BackgroundThe application of advanced 3T MRI imaging techniques to study recovery after subarachnoid hemorrhage (SAH) is complicated by the presence of image artifacts produced by implanted aneurysm clips. To characterize the effect of these artifacts on image quality, we sought to: 1) quantify extent of image artifact in SAH patients with implanted aneurysm clips across a range of MR sequences typically used in studies of volumetry, blood oxygen level dependent signal change (BOLD-fMRI), and diffusion-weighted imaging (DW-MRI) and 2) to explore the ability to reconstruct white matter pathways in these patients.MethodsT1- and T2-weighted structural, BOLD-fMRI, and DW-MRI scans were acquired at 3T in two patients with titanium alloy clips in ACOM and left ACA respectively. Intensity-based planimetric contouring was performed on aligned image volumes to define each artifact. Artifact volumes were quantified by artifact/clip length and artifact/brain volume ratios and analyzed by two-way (scan-by-rater) ANOVAs. Tractography pathways were reconstructed from DW-MRI at varying distances from the artifacts using deterministic methods.ResultsArtifact volume varied by MR sequence for length (p = 0.007) and volume (p < 0.001) ratios: it was smallest for structural images, larger for DW-MRI acquisitions, and largest on fMRI images. Inter-rater reliability was high (r = 0.9626, p < 0.0001), and reconstruction of white matter connectivity characteristics increased with distance from the artifact border. In both patients, reconstructed white matter pathways of the uncinate fasciculus and inferior fronto-occipital fasciculus were clearly visible within 2 mm of the artifact border.ConclusionsAdvanced 3T MR can successfully image brain tissue around implanted titanium aneurysm clips at different spatial ranges depending on sequence type. White matter pathways near clip artifacts can be reconstructed and visualized. These findings provide a reference for designing functional and structural neuroimaging studies of recovery in aSAH patients after clip placement.

【 授权许可】

Unknown   
© Khursheed et al; licensee BioMed Central Ltd. 2011. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.