- Axial T1
- Axial T2
- Axial STIR
- Coronal T1
- Coronal STIR
- Sagittal STIR
- Axial T1 Fat Sat
- Coronal T1 Fat Sat
The routine examination is performed with the patient lying supine with the foot positioned in an extremity coil. Alternatively the forefoot may be imaged in the prone position with the toes in an extremity coil. The foot is normally placed in the neutral position but may be plantar flexed if there is concern regarding the tendons.
T1 Anatomically detailed with high resolution. Sensitive for bone marrow changes, however may miss bone marrow edema in the smaller phalanges.
T2 Less sensitive to bone marrow edema, especially when fast spin echo sequences are employed due the bright signal of edema blending with the bright signal of the fatty bone marrow. T2 with fat saturation avoids this problem, but the foot may difficult to obtain a uniform fat saturation. Inhomogeneous fat saturation may lead to diagnostic error.
STIR Very sensitive to bone marrow edema changes. Uniform fat saturation easily obtained.
Intavenous gadolinium is generally not needed on a routine basis. It may improve sensitivity for small abscesses or sinus tracts.
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