Skip to main content
padlock icon - secure page this page is secure

Local magnetic field perturbations caused by magnetic susceptibility heterogeneity in myelin-water layers within an axon

Buy Article:

$106.51 + tax (Refund Policy)

Magnetic resonance imaging has been used to map the myelin water fraction in neural tissue. One hypothesis is that a reduction in T*2 arises from microscopic perturbations in the magnetic field caused by heterogeneities in the magnetic susceptibility of myelin. In this paper, the perturbed magnetic field distribution is calculated analytically using a perturbation expansion written in terms of a small dimensionless parameter corresponding to the magnetic susceptibility. When the magnetic field is applied perpendicular to the axon, the magnetic field in the intracellular space is not influenced by the myelin, the magnetic field in the myelin sheath oscillates between the fat and water layers, and the magnetic field in the extracellular space just outside the myelin sheath is heterogeneous. This heterogeneity causes the spins to dephase, shortening T*2. When the magnetic field is applied along the axon, it is homogeneous within water-filled regions between myelin layers, and therefore the spins will not dephase and the magnetic susceptibility will have no effect on T*2. These two solutions predict the perturbed magnetic field distribution in and around an axon arbitrarily oriented in the main magnetic field.
No Reference information available - sign in for access.
No Citation information available - sign in for access.
No Supplementary Data.
No Article Media
No Metrics

Keywords: MAGNETIC RESONANCE IMAGING; MYELIN; MYELIN WATER IMAGING; PERTURBATION; SUSCEPTIBILITY

Document Type: Research Article

Publication date: September 1, 2015

  • Access Key
  • Free content
  • Partial Free content
  • New content
  • Open access content
  • Partial Open access content
  • Subscribed content
  • Partial Subscribed content
  • Free trial content
Cookie Policy
X
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more