Learning objectives
Acute benign and malignant fractures of the spine may have similar signal intensity characteristics on conventional MR imaging sequences.
Apart from the routine spine evaluation on MRI by T1-weighted,
T2-weighted and FSEIR sequences,
chemical shift and diffusion weighted imaging may be useful in differentiating acute benign compression fractures from malignant infiltration and pathologic fractures.
Background
Benign vertebral lesions can occur in cancer patients.
Metastatic vertebral lesions frequently account for bony metastases in patients with primary neoplasm.
Differentiation between malignant and benign vertebral compression fracture in acute setting is difficult especially for patients known with or suspected primary neoplasm.
Routine MRI of the spine typically includes T1-weighted,
T2-weighted and FSEIR sequences,
may provide useful evaluation of the benign and malignant vertebral fracture based on morphological features.
Lesions with negative gadolinium enhancement were favored as benign fractures.
A uniform signal change in...
Imaging findings OR Procedure details
Chemical shift imaging applies principle that fat and water protons in a single voxel show slightly different precession frequencies.
Using a 1.5-T magnet,
water and fat protons are in phase with one another at a TE of 4.6 milliseconds.
At a TE of 2.4 milliseconds,
water and fat are 180° opposed; thus,
the signals of water and fat cancel each other.
In normal bone marrow with the presenceof both fat and water,
signal loss will occur on the out-of-phase images as compared with the in-phase...
Conclusion
Chemical shift and diffusion-weighted MR imaging can provide excellent distinction between malignant and benign acute vertebral compression fractures especially for the patient with known metastatic tumor.
References
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Diffusion weighted...