CT and MRI findings of the incidental intraosseous lipomatous lesions of the sphenoid bone.

BACKGROUND Intraosseous lipomatous lesions of the sphenoid bone and skull base are increasingly seen and cause a diagnostic challenge. The purpose of this study was to present the imaging findings of 4 patients with incidentally identified intraosseous lipomatous lesions within the sphenoid bone. METHODS CT scans and MR images of 4 patients are shown. Macroscopic fat content of the lesions were evaluated by fat-saturated sequences on MRI and by measuring fat density in Hounsfield Units on CT. RESULTS The most striking imaging findings of these well-defined lesions were their fat content, preservation of foramina, and absence of cortical destruction. CONCLUSION Intraosseous lipomatous lesions are asymptomatic, fat containing, non-touch lesions that should be recognized to prevent unnecessary further investigation, such as biopsy.