Cornelia Laule1
1University of British Columbia, Canada
Synopsis
Keywords: Neuro: White matter, Neuro: Brain, Neuro: Spinal cord
This
presentation will provide an introduction to myelin water imaging (MWI), a
quantitative MRI technique that can detect myelin in vivo. MWI was first
proposed in the early 1990s as a method to measure the water trapped between
the myelin bilayers in brain tissue. They used a multi-echo T
2 relaxation
sequence fit to a multi-exponential model to quantify signal arising from
myelin water, as well as intra- and extra-cellular water, and subsequently
applied MWI to study multiple sclerosis. Since then, MWI has been improved,
validated and applied to various neurological disorders and healthy populations
by many researchers around the world.
KEY POINTS
-
Myelin is a complex lipid-protein bilayer
that surrounds axons and enables rapid signal transmission
- Myelin water imaging (MWI) is a
quantitative MRI technique than can use a multi-echo T2
relaxation sequence to measure water trapped between myelin bilayers
- Historically challenged by lengthy acquisition
and analysis times, the field of MWI is rapidly changing due to new advances
in pulse sequence, analysis, validation and applications
- MWI has been histopathologically validated
as a biomarker for myelin in human tissue and animal models
- Demyelination and remyelination can
be detected using MWI in many neurological diseases and injuries, both in
focal regions and in subtle abnormalities in normal appearing brain and
spinal cord tissues that are not visible on conventional MRI
- MWI has applications in studying
the development, aging and disease of the human brain and spinal cord
TARGET AUDIENCE
- Clinicians and imaging
scientists who are interested in the basics of myelin water imaging in central
nervous system and its potential uses in neuroscience.
LEARNING OBJECTIVES
By the end of this presentation, the audience will be able to:
-
Describe the structure of myelin
and it’s role in central nervous system health and function
- Explain some basic principles and
methods of MWI
- Identify the main brain and spinal
cord regions that show variation in myelin water fraction (MWF)
-
Recognize the patterns of MWF changes
in different neurological disorders
- Describe the advantages and
limitations of MWI compared to other MRI techniques
Evaluate the current challenges and
future directions of MWI research
SUMMARY
This presentation will
provide an introduction to MWI, a quantitative MRI technique that measures
myelin water and can detect demyelination and remyelination in vivo. MWI was
first proposed by MacKay et al in the early 1990s as a method to measure the
water trapped between the myelin bilayers in brain tissue. They used a
multi-echo T2 relaxation sequence fit to a multi-exponential model to quantify
signal arising from myelin water, as well as intra- and extra-cellular water,
and subsequently applied MWI to study multiple sclerosis. Since then, MWI has
been improved, validated and applied to various neurological disorders and
healthy populations by many researchers around the world. The presentation will
cover an overview, motivation, historical perspective and classical solutions
of MWI. The presentation will also briefly touch on the applications of MWI in
studying the development, aging and disease of the human brain and spinal cord,
as well as the current challenges and future directions of MWI research.ONLINE RESOURCES & RECOMMENDED READING
Some
tutorials and videos on MWI:
Some
reviews and meta-analyses on MWI and myelin imaging:
Some
recent publications on MWI:
Some
key early publications on T
2 relaxation and MWI:
Acknowledgements
Sincere thanks goes to the many study volunteers, tissue donors, families and the wonderful staff at the UBC MRI Research Centre. Some work presented in this talk was funded by the Multiple Sclerosis Society of Canada, Natural Sciences and Engineering Research Council of Canada (NSERC), Craig H. Neilsen Foundation, International Collaboration on Repair Discoveries, and the VGH and UBC Hospital
Foundation.
Work presented in this talk was, in part, conducted on the traditional and ancestral territories of Coast Salish Peoples, including the territories of the xwməθkwəy̓əm (Musqueam), Skwxwú7mesh (Squamish), Stó:lō and Səl̓ílwətaʔ/Selilwitulh (Tsleil- Waututh) Nations. These territories are unceded, meaning that the land has never been legally ceded, surrendered, relinquished, or handed over in any way through a treaty or any other agreement by the Indigenous People to the Crown/European settlers.
References
No reference found.