Magnetic resonance imaging derived biomarkers in multiple sclerosis

Simple item page
dc.contributor.advisorMitchell, J. Ross
dc.contributor.authorZhang, Yunyan
dc.date.accessioned2017-12-18T21:20:21Z
dc.date.available2017-12-18T21:20:21Z
dc.date.issued2007
dc.descriptionBibliography: p. 143-172en
dc.description.abstractSeveral mechanisms contribute to the complex pathophysiology of multiple sclerosis (MS). This calls for biomarkers to characterize the heterogeneity of MS in individual subjects. The advancement in magnetic resonance imaging (MRI) technology over past decades makes it the most attractive biomarker candidate in MS. Texture analysis was applied to quantify subtle abnormalities on the MRI from people with MS. A classical statistical method (gray level co-occurrence matrix) was able to detect a tread yet not significant difference of therapeutic responses between different tissue types. A novel time-frequency based technique (polar Stockwell Transform, PST) was then investigated. The increased PST texture was shown to represent inflammation and demyelination in a murine model of MS. PST texture altered significantly when tissue MRI evolved from normal appearing white matter to MS lesions. It decreased significantly when an active lesion became inactive. This suggests that the PST texture may be a MRI surrogate to characterize subtle and early abnormalities existed in MS tissue. MS is also a neurodegenerative disease in the central nervous system (CNS) affecting both white matter and grey matter (GM). Abnormally decreased signal intensity (black T2, BT2) in the deep GM of MS patients was noted on 1.5 T MRI. Due to the iron deposition phenomenon in its underlying tissue, 3 T MRI was more sensitive to BT2 detection than 1.5 T MRI. A higher correlation was obtained between patient disability and deep GM BT2 measured at 3 T than that at 1.5 T in MS. The association of 3 T BT2 with EDSS was greater than most of the MRI derived indices in MS. The small sample size limits broad conclusions. However, these results encourage further investigation of the clinical significance of BT2 as a biomarker for disability in MS at high field. This thesis provides evidence for proof of concept that the new developed techniques may have potential to become surrogate measures in MS diagnostics and treatment. However, these techniques need to be combined with other MRI matrices in order to obtain an integrated picture of MS.
dc.format.extentxxiv, 172 leaves : ill. ; 30 cm.en
dc.identifier.citationZhang, Y. (2007). Magnetic resonance imaging derived biomarkers in multiple sclerosis (Doctoral thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca. doi:10.11575/PRISM/1033en_US
dc.identifier.doihttp://dx.doi.org/10.11575/PRISM/1033
dc.identifier.urihttp://hdl.handle.net/1880/102034
dc.language.isoeng
dc.publisher.institutionUniversity of Calgaryen
dc.publisher.placeCalgaryen
dc.rightsUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.
dc.titleMagnetic resonance imaging derived biomarkers in multiple sclerosis
dc.typedoctoral thesis
thesis.degree.disciplineBiomedical Engineering
thesis.degree.grantorUniversity of Calgary
thesis.degree.nameDoctor of Philosophy (PhD)
ucalgary.item.requestcopytrue
ucalgary.thesis.accessionTheses Collection 58.002:Box 1766 520492283
ucalgary.thesis.notesUARCen
ucalgary.thesis.uarcreleaseyen
Files
Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
thesis_Zhang_2007.pdf
Size:
81.41 MB
Format:
Adobe Portable Document Format
Description:
Thesis
Download
Collections
Legacy Theses