Findings of subarachnoid fat after trauma to a tarlov cyst

Subarachnoid fat is an uncommon finding that has several etiologies. It is important to determine the etiology in order to plan appropriate treatment. We present a case report of an 80-year-old female brought to the emergency department after a fall with complaints of headache and pain in the sacral region. Computed tomography and magnetic resonance images of the head demonstrated fat in the subarachnoid space. Computed tomography and magnetic resonance images of the sacrum demonstrated a Tarlov cyst with a sacral fracture extending into the cyst, likely representing the origin of the fat in the subarachnoid space. This case demonstrates a rare etiology of fat in the subarachnoid space.