Table 1.
Head magnetic resonance imaging protocol
| Parameters | Description |
|---|---|
| Electromagnetic field | Images should be of good quality with an appropriate SNR value and resolution (≤ 1 × 1 mm) |
| Reference setting | When setting the scanning plane, use a line parallel to the lower edges of the rostrum and splenium of the corpus callosum, also to have an identical angulation of the planned slices to the angulation of the slices in the previous study (Figure 1) |
| Scanning range | Whole brain scanned |
| Slice thickness and gaps | ≤ 3 mm, with no gaps (for 2D and 3D acquisitions) |
| Basic sequences | 1. 3DT1 axial isotropically 2. T2 axial 3. Axial DWI (with ADC map) Administration of a contrast medium1 (T1 sequence 5-10 minutes after administration!) 4. FLAIR + C sagittal 5. FLAIR + C axial 6. 3DT1 + C axial isotropically2 1The recommended dose of a contrast medium is 0.1 mmol/kg body mass, see General comments. 2 It is recommended that sagittal reconstructions are performed and recorded, and archived on a CD and in the PACS system, if available, as an integral part of the examination. |
| Optional sequences | 1. PD 2. SWI (for the identification of central veins in lesions and microbleedings) 3. DIR – for evaluation of cortical and subcortical foci |
1.The direction of scanning in axial scans must be upwards, whereas in sagittal scans it must be from the right to the left (also when scanning the spine).
2. Gaps between slices should be as small as possible (proposed 0.3 mm, i.e. 10% slice thickness).
3. 3DT1 – it is recommended that this sequence be performed first, to avoid motion artefacts in the course of the examination. This is a sequence necessary for precise volumetric evaluation of the brain.
4. Both FLAIR sequences should be performed after the administration of a contrast medium, to delay the onset of T1 + C acquisition (within the range of 5-10 minutes), in order to achieve better contrast enhancement. A contrast medium does not affect the quality of FLAIR images, and at the same time the patient’s time spent in the scanner is used optimally.
5. If scanning with 3DT2 and 3D FLAIR sequences is possible, they should be used with subsequent axial reconstruction with 3 mm slices in the plane set up to the lower edge of the corpus callosum.
6. If a software which automatically determines the angulation/range of the layers can be used, as in the previous examination, such a function is recommended.