Lipids in bone tumors assessed by magnetic resonance: chemical shift imaging and proton spectroscopy in vivo.

The methods of fat and water selective magnetic resonance (MR) imaging and localized 1H MR spectroscopy were evaluated in the course of 37 examinations on 27 primary bone tumors. These methods are capable of demonstrating small amounts of lipids inside the tumors and subtle edema in the adacent bone marrow, in contrast to the usually applied spin-echo and gradient-echo sequences providing signals dependent on the total proton density and on the relaxation times. The tumor masses of the malignant tumors were free of signals in the fat selective images, whereas in three out of six osteochondroma fat signals could be detected. Localized MR spectroscopy was more sensitive even to very low lipid content (lipid portion < 0.5%) in the tumors and revealed signals with J-coupling from seven out of 13 malignant tumors.