Diapositiva 1

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Magnetic Resonance Imaging techniques on
Multiple Sclerosis
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Diagnosis of MS MRI criteria
Fazekas criteria (1988) 3 or more lesions of
which 2 with the following characteristics
diameter gt 5mm close to lateral ventricle
location Infratentorial locations Sensibil
ity 87 Specificity 94
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MRI findings in predicting clinically definite MS

• Barkhof criteria (1997)
• Almost 3 of these findings
• 1 enhancing lesion or 9 T2 hyperintense lesions
  if no enhancing lesion
• 1 lesion located subcortically
• 3 lesion located periventricularly
• 1 lesion located infratentorially

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McDonald criteria (2001) Recommanded
diagnostic criteria for MS Ann Neurol
501221-127
Dissemination in time
Dissemination in space

• A Gd-enhancing lesion in a scan perfomed at least
  3 months after the onset of the clinical event,
  provided that it is not at the site implicated in
  the original clinical event.
• If no enhancing lesion is seen at this second
  scan, a further scan not less than 3 months after
  the first scan that shows a new T2 lesion or an
  enhancing lesion will suffice

• 9 or more brain T2-hyperintense lesions
• Or
• 2 or more spinal lesions
• Or
• 4-8 brain lesions and 1 spinal lesion

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MRI T2-weighted imagesAcquisition mode

• Double-echo sequences
• Conventional Spin-echo
• Fast / turbo spin-echo (reduced time for the
  procedure)
• FLAIR sequences
• null out liquoral signal
• increased T2 weight
• increased sensibility to MS lesions (
  periventricular and juxtacortical regions)

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MS PD and T2-weighted images
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MS FLAIR images
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MS T1-weighted images
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Common location of MS lesions MRI findings
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Common locations Periventricular
Axial PD sequence. Left and right images show
lesions located periventricularly
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Common locations Cortico-subcortical
Axial fast-FLAIR sequence. Right image shows
lesions (arrows) located at the
cortico-subcortical location
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Common locations Corpus Callosum (CC)
Sagittal T2 (left), and enhanced T1 (right). Left
image shows a lesion located at level of the CC
body that enhances after injection of Gd-DTPA
(right)
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Common locations Trigeminal cranial nerve
Axial T2 (left), and enhanced T1 (right). Left
image shows a lesion (arrow) located at level of
the 5th cranial nerve that enhances after
injection of Gd-DTPA (right)
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Common locations Infratentorial
regions Brainstem
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Common locations Optical nerve
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Common locations Spinal cord
Sagittal T2 (left), and enhanced T1 (right) of
cervical spine. Left image show lesions located
at C1 and C5-C6 levels which enhance after
injection of Gd-DTPA (right)
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Common locations Spinal cord
Sagittal T2 (left), and enhanced T1 (right) of
spine. Left image shows a lesion located at
level of the thoracic spinal cord that enhances
after injection of Gd-DTPA (right)