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A laminectomy can treat severe spinal stenosis by relieving pressure on the spinal cord or nerve roots, provide access to a tumor or other mass lying in or around the spinal cord, or help in tailoring the contour of the vertebral column to correct a spinal deformity such as kyphosis.
The key to Phase-contrast MRI (PC-MRI) is the use of a bipolar gradient. [4] A bipolar gradient has equal positive and negative magnitudes that are applied for the same time duration. The bipolar gradient in PC-MRI is put in a sequence after RF excitation but before data collection during the echo time of the generic MRI modality.
Nowadays, MRI has all but replaced myelography. [4] MRI is preferable because injection of contrast medium into the spinal canal is infrequently needed for better images. However, a CT myelogram may be useful for patients who cannot undergo MRI (e.g., those with pacemakers or cochlear implants). CT is preferred when MRI images are limited by ...
Functional magnetic resonance imaging (fMRI) of the spinal cord (spinal fMRI) is an adaptation of the fMRI method that has been developed for use in the brain. Although the basic principles underlying the methods are the same, spinal fMRI requires a number of specific adaptations to accommodate the periodic motion of the spinal cord, the small cross-sectional dimensions (roughly 8 mm × 15 mm ...
MRI provides better resolution of tissue density, absence of bone interference, multiplanar capabilities, and is noninvasive. Plain films may show bony erosion of the spinal canal or of the sacral foramina. [citation needed] On MRI pictures, the signal is the same as the CSF one. If MRI made with a contrast medium: [citation needed]
T2*-weighted imaging of the brain 26 weeks after subarachnoid hemorrhage, showing hemosiderin deposits as hypointense areas. [1] T 2 *-weighted imaging is an MRI sequence to quantify observable or effective T 2 (T2* or "T2-star"). In this sequence, hemorrhages and hemosiderin deposits become hypointense. [2]
Diffusion imaging is an MRI method that produces in vivo magnetic resonance images of biological tissues sensitized with the local characteristics of molecular diffusion, generally water (but other moieties can also be investigated using MR spectroscopic approaches). [15]
An MRI pulse sequence in magnetic resonance imaging (MRI) is a particular setting of pulse sequences and pulsed field gradients, resulting in a particular image appearance. [ 1 ] A multiparametric MRI is a combination of two or more sequences, and/or including other specialized MRI configurations such as spectroscopy .