Incidental nondysraphic cervical intradural extramedullary lipoma at C1-C2: CT and MRI findings.

Intradural lipomas are rare benign tumors, accounting for less than 1% of all spinal tumors. Their exact physiopathology is not fully understood. There are many theories that share some basic aspects. Cervical intradural lipomas not associated with dysraphism are even rarer. We report the case of an incidental finding of a nondysraphic cervical intradural lipoma in a 17-year-old male patient initially admitted for polytrauma management. Whole-body trauma CT revealed a well-circumscribed intradural extramedullary fat-density lesion within the left dorsolateral spinal canal at the C1-C2 level, demonstrating attenuation values consistent with fat and mild mass effect on the adjacent cervical cord without significant canal compromise. MRI confirmed a homogeneous lesion hyperintense on T1-weighted images, intermediate-to-hyperintense on T2-weighted images, with complete signal suppression on fat-saturated sequences and no enhancement or cord signal abnormality. As the patient was asymptomatic, a conservative management approach was implemented with annual MRI follow-up and clinical evaluation.