Fig 1.

A 45-year-old man with several months of night-time predominant, right-sided midthoracic pain relieved by ibuprofen. A, Prone axial noncontrast CT image shows a small osteolytic lesion with a central mineralization in the right T5 superior articular facet (black arrow). B, Prone axial noncontrast CT image shows the radiofrequency ablation probe in the nidus of the osteoid osteoma (black open arrow). C, Prone axial noncontrast CT image shows an 18-ga spinal needle placed in the right T4–T5 neural foramen for temperature monitoring, carbon dioxide injection, and cooled dextrose 5% in water infusion. Note the gas tracking into the soft tissue and within the epidural space (white arrow).