Article: Effect of cerebrovascular changes on brain DTI quantitation: a hypercapnia study
| Title | Effect of cerebrovascular changes on brain DTI quantitation: a hypercapnia study |
|---|---|
| Authors | Ding, AY1 Chan, KC1 Wu, EX1 |
| Keywords | Cerebrovasculature Diffusivity Dti Hemodynamics Hypercapnia Quantitation |
| Issue Date | 2012 |
| Publisher | Elsevier Inc. The Journal's web site is located at http://www.elsevier.com/locate/mri |
| Citation | Magnetic Resonance Imaging, 2012 [How to Cite?] DOI: http://dx.doi.org/10.1016/j.mri.2012.02.012 |
| Abstract | Quantitative diffusion tensor imaging (DTI) offers a valuable tool to probe the microstructural changes in neural tissues in vivo, where absolute quantitation accuracy and reproducibility are essential. It has been long recognized that measurement of apparent diffusion coefficient (ADC) using DTI could be influenced by the presence of water molecules in cerebrovasculature. However, little is known about to what extent such blood signal affects DTI quantitation. In this study, we quantitatively examined the effect of cerebral hemodynamic change on DTI indices by using a standard multislice echo planar imaging (EPI) spin echo (SE) DTI acquisition protocol and a rat model of hypercapnia. In response to 5% CO 2 challenge, mean, radial and axial diffusivities measured with diffusion factor (b-value) of b=1.0 ms/μm 2 were found to increase in whole brain (1.52%±0.22%, 1.66%±0.16% and 1.35%±0.37%, respectively), gray matter (1.56%±0.23%, 1.63%±0.14% and 1.47%±0.45%, respectively) and white matter regions (1.45%±0.28%, 1.88%±0.33% and 1.10%±0.26%, respectively). Fractional anisotropy (FA) was found to decrease by 1.67%±0.38%, 1.91%±0.59% and 1.46%±0.30% in whole brain, gray matter and white matter regions, respectively. In addition, these diffusivity increases and FA decreases became more pronounced at a lower b-value (b=0.3 ms/μm 2). The results indicated that in vivo DTI quantitation in brain can be contaminated by vascular factors on the order of few percentages. Consequently, alterations in cerebrovasculature and hemodynamics can affect the DTI quantitation and its efficacy in characterizing the neural tissue microstructures in normal and diseased states. Caution should be taken in designing and interpreting quantitative DTI studies as all DTI indices can be potentially confounded by physiologic conditions and by cerebrovascular and hemodynamic characteristics. © 2012 Elsevier Inc. All rights reserved. |
| ISSN | 0730-725X 2011 Impact Factor: 1.991 2011 SCImago Journal Rankings: 0.193 |
| DOI | http://dx.doi.org/10.1016/j.mri.2012.02.012 |
| dc.contributor.author | Ding, AY |
|---|---|
| dc.contributor.author | Chan, KC |
| dc.contributor.author | Wu, EX |
| dc.date.accessioned | 2012-08-08T08:35:08Z |
| dc.date.available | 2012-08-08T08:35:08Z |
| dc.date.issued | 2012 |
| dc.description.abstract | Quantitative diffusion tensor imaging (DTI) offers a valuable tool to probe the microstructural changes in neural tissues in vivo, where absolute quantitation accuracy and reproducibility are essential. It has been long recognized that measurement of apparent diffusion coefficient (ADC) using DTI could be influenced by the presence of water molecules in cerebrovasculature. However, little is known about to what extent such blood signal affects DTI quantitation. In this study, we quantitatively examined the effect of cerebral hemodynamic change on DTI indices by using a standard multislice echo planar imaging (EPI) spin echo (SE) DTI acquisition protocol and a rat model of hypercapnia. In response to 5% CO 2 challenge, mean, radial and axial diffusivities measured with diffusion factor (b-value) of b=1.0 ms/μm 2 were found to increase in whole brain (1.52%±0.22%, 1.66%±0.16% and 1.35%±0.37%, respectively), gray matter (1.56%±0.23%, 1.63%±0.14% and 1.47%±0.45%, respectively) and white matter regions (1.45%±0.28%, 1.88%±0.33% and 1.10%±0.26%, respectively). Fractional anisotropy (FA) was found to decrease by 1.67%±0.38%, 1.91%±0.59% and 1.46%±0.30% in whole brain, gray matter and white matter regions, respectively. In addition, these diffusivity increases and FA decreases became more pronounced at a lower b-value (b=0.3 ms/μm 2). The results indicated that in vivo DTI quantitation in brain can be contaminated by vascular factors on the order of few percentages. Consequently, alterations in cerebrovasculature and hemodynamics can affect the DTI quantitation and its efficacy in characterizing the neural tissue microstructures in normal and diseased states. Caution should be taken in designing and interpreting quantitative DTI studies as all DTI indices can be potentially confounded by physiologic conditions and by cerebrovascular and hemodynamic characteristics. © 2012 Elsevier Inc. All rights reserved. |
| dc.description.nature | Link_to_subscribed_fulltext |
| dc.identifier.citation | Magnetic Resonance Imaging, 2012 [How to Cite?] DOI: http://dx.doi.org/10.1016/j.mri.2012.02.012 |
| dc.identifier.citeulike | 10551703 |
| dc.identifier.doi | http://dx.doi.org/10.1016/j.mri.2012.02.012 |
| dc.identifier.issn | 0730-725X 2011 Impact Factor: 1.991 2011 SCImago Journal Rankings: 0.193 |
| dc.identifier.scopus | eid_2-s2.0-84864006582 |
| dc.identifier.uri | http://hdl.handle.net/10722/155745 |
| dc.language | eng |
| dc.publisher | Elsevier Inc. The Journal's web site is located at http://www.elsevier.com/locate/mri |
| dc.publisher.place | United States |
| dc.relation.ispartof | Magnetic Resonance Imaging |
| dc.subject | Cerebrovasculature |
| dc.subject | Diffusivity |
| dc.subject | Dti |
| dc.subject | Hemodynamics |
| dc.subject | Hypercapnia |
| dc.subject | Quantitation |
| dc.title | Effect of cerebrovascular changes on brain DTI quantitation: a hypercapnia study |
| dc.type | Article |
Author Affiliations
- The University of Hong Kong