MRI Protocol for fMRI used in the mapping of cortical functions during 1997-9

T2 * Gradient Echo EPI Head protocols

This multi-phase acquisition acquires 128 images per location BOLD sequence (Blood Oxygenation Level Dependent)

Ramp Sampling = 1

  • Type .......................................................................................T2 *
  • PL .......................................................................................... A/C/S/o
  • MD ..........................................................................................2D
  • PSD ........................................................................................ GRE
  • Options ....................................................................................EPI/FC/VB/Multiphase
  • TR ...........................................................................................3000
  • TE ...........................................................................................60
  • Shots .......................................................................................1
  • FOV .........................................................................................40(1/2)
  • Flip Angle .................................................................................90
  • Thickness .................................................................................10mm
  • Spacing ....................................................................................2
  • Location ...................................................................................4
  • Matrix ......................................................................................128 x 128
  • NEX ..........................................................................................1
  • Freq .........................................................................................R/L
  • Time ........................................................................................6:24
128 images for a single slice show changes the brain's activity during a six minute window

Image acquisition is time-locked to cognitive activity, usually in an alternating, activation/no activation condition, or activation/other activation pattern. Image acquisition during alternations takes into account mean blood flow change characteristics (4.6 sec delay to peak change). While BOLD sequences are not the only fMRI protocol, they seem at this time to be the most reliable for detecting and presenting a variety of clinical conditions.

Team Approach: From the outset, one key to providing fMRI services is to adopt a team-based approach. The multiplicity of knowledge used in these services crosses the domains of clinical medicine (neuroradiology), physics (MR protocols), computer science (image acquisition, storage, transmission & retrieval), neuropsychology (cognitive neuropsychological tasks), neuroscience (brain chemistry) and statistics (image analysis).