Fat embolism syndrome complicates open fractures involving long bones, although it occasionally follows nontraumatic conditions. Incomplete forms of the syndrome (ie, cerebral fat embolism) represent a challenge to diagnosis, and brain MRI represents a valuable diagnostic tool. We describe a patient who had a fat embolism to the brain after an isolated traumatic open fracture of the tibia. MRI with T2 and diffusion-weighted images revealed multiple, reversible brain lesions, suggesting vasogenic edema and consistent with this entity. At present, MR imaging is the most sensitive technique to evaluate cerebral fat embolism.