Classic Case

Intracortical pneumatocyst is a rare, benign, innocuous, gas-filled lesion, mostly seen in a cervical vertebra. The etiology of cervical pneumatocyst is unclear. CT is considered the best imaging modality to delineate the extent of the gaseous lesion. The classic CT imaging finding is a well-defined and gas-filled (HU-1023) intracortical lesion with internal septation (A–C, arrows). This condition should be differentiated from Kummel disease, geode, and osteolipoma by the characteristic imaging findings of pneumatocyst, showing a normal-appearing adjacent vertebral body and intervertebral discs and no collapsed vertebra. Follow-up is necessary to document growth of the lesion after 12 months or if symptomatic.