Download presentation
Presentation is loading. Please wait.
Published byErica French Modified over 5 years ago
1
Imaging protocols for the brain should meet several criteria:
They must be as short as possible (to minimize the time the patient has to spend in the magnet and optimize patient throughput) They must be reproducible Protocols should be standardized to ensure continuity over time. Frequent changes in imaging protocols should be avoided, Imaging protocols should be adapted to the equipment available.
2
Patient preparation The patient should go to the toilet before the study Explain the procedure to the patient Offer the patient ear plugs or ear protectors Ask the patient to remove anything containing metal (dentures, hearing aid, hairpins, body jewelry, ear rings, etc.) If necessary have an intravenous line placed (e.g., investigation for tumor or multiple sclerosis) Ensure that the patient has understood and filled out the questionnaire(with special reference to metallic objects)
3
(phased-array head coils) is used
Coils and Positioning Coil Choice Traditionally (Head coils) is used Recently (phased-array head coils) is used because it can be used to speed up MRI
4
Imaging Planes Imaging sequences can be started in true Sagittal, Coronal, or Axial planes The following anatomical landmarks should be identified: 1. Corpus callosum (over its entire length), 2. Sylvain aqueduct 3. Fourth ventricle 4. Cervical spinal cord
5
Patient Positioning Patient head should be centered at the brain coil, chin pointing upward Patient should use earplugs for hearing protection with additional headsets and/or immobilization pads should be placed around the head to reduce the noise and gross patient motion. The head should also be fixed with additional straps for further patient motion reduction while keeping patient safety and comfort as a priority. Place the leg support pads for patient comfort. After land marking the center of the brain coil or just below the eyes using laser marker lights (while the eyes are closed) or touch sensors, you can send the patient in and start the exam
6
Sagittal, Coronal, or Axial planes
Imaging Planes An MRI examination of the brain begins with one (or more) fast localizer scans (also known as scout or survey images). Imaging sequences can be started in true Sagittal, Coronal, or Axial planes The following anatomical landmarks should be identified: Corpus callosum (over its entire length), Sylvain aqueduct Fourth ventricle Cervical spinal cord
8
Sequence 1 (T2-weighted) TSE: -TR = 3500–4500 - TE = 100–120
Planning Axial slices should be positioned parallel to the bicommissural line, which links the anterior to the posterior commissure (yellow line). Alternatively, axial slices can be oriented parallel to a line linking the floor of the sella turcica to the fastigium of the fourth ventricle (lower dotted line). A third alternative solution is to position slices parallel to a line linking the inferior borders of the genu and splenium of the corpus callosum ( upper dotted line ). In most (adult) patients, these imaging planes differ by only a few degrees. For coronal scans, we prefer a plane parallel to the posterior surface of the brainstem ( blue dotted line )
Similar presentations
© 2024 SlidePlayer.com. Inc.
All rights reserved.