Brain and Skull
Patient preparation
— Have the patient 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)
Positioning
— Supine
— Secure the head in the head coil
— Cushion the legs
Sequences
— Scout: three planes (or sagittal and axial)
Sequence 1 axial (plot on central sagittal plane, line through anterior and
posterior margin of the corpus callosum [parallel to a line running
through the anterior and posterior commissure]; enough scans to delineate
the brain completely from the vertex to the cerebellum usually to
the line of the foramen magnum)
T2-weighted
Example
TSE:
— TR = 3500–4500
— TE = 100–120
— Slice thickness: 5–6mm
— Slice gap: 20% of slice thickness (!1–1.2mm or factor 1.2)
— Matrix: 512
— FOV: 220–240mm
— Saturation slab: parallel to the slices, inferior to the most caudad slice
(50–80 mm)