The retrodural space of Okada and its relevance to CT guided intervention.

The spinal epidural and posterior ligamentous complex spaces are important anatomic regions which are the target of various radiologic procedures in the cervical, thoracic and lumbar spine for the purpose of analgesia and anaesthesia. Given the frequency with which procedures are performed in and around the epidural space, a sound understanding of the associated anatomy is paramount to ensure the safety and efficacy of procedural intervention.