BONE CONTUSIONS OF THE KNEE - INCREASED LESION DETECTION WITH FAST SPIN-ECHO MR-IMAGING WITH SPECTROSCOPIC FAT-SATURATION

PURPOSE: To demonstrate that T2-weighted fast spin-echo (FSE) imaging with spectroscopic fat saturation (FS-FSE) increases the conspicuity b etween normal marrow and bone contusions in posttraumatic knees. MATER IALS AND METHODS: Seventy-six magnetic resonance (MR) studies of the k nee were prospectively evaluated in 73 consecutive patients with knee pain. Conspicuity of regions of microtrabecular trauma (bone contusion s) was evaluated with conventional T2-weighted imaging in the sagittal plane, T2-weighted FSE imaging in the coronal plane, T2-weighted FS-F SE imaging in the sagittal plane, and conventional T1-weighted imaging in the sagittal plane. RESULTS: Twenty-six foci of bone contusion wer e identified in 21 knees with the FS-FSE technique. Only 16 foci were demonstrated with conventional T2-weighted imaging. Six of the sites o f bone contusion were not demonstrated with the FSE technique alone (w ithout fat saturation). Four of the bone contusions were not seen on T 1-weighted images; these sites of bone contusion were substantially mo re conspicuous on the FS-FSE images. In addition, FS-FSE imaging was m ore sensitive in demonstrating the extent of microtrabecular trauma. C ONCLUSION: T2-weighted FS-FSE imaging is a sensitive and rapid method of identifying and assessing the extent of microtrabecular trauma abou t the knee.