Retro-odontoid pseudotumor: a potentially serious cervical spine incidental finding on cone beam computed tomography

Retro-odontoid pseudotumor (ROP) is a benign proliferation of soft tissues posterior to the odontoid process. It can be associated with both inflammatory and noninflammatory arthritis. Altered biomechanics and atlantoaxial instability are the major contributing factors. There are no characteristic clinical findings. In the majority of cases, ROP is detected as an incidental finding in imaging. Early diagnosis of the lesion is important because of its proximity to the spinal canal and spinal cord. Clinical signs and symptoms range from pain to paralysis depending on the presence and level of spinal cord compression. In very rare cases, the lesion might cause sudden death of the patient. We report a case of ROP detected as an incidental finding in cone beam computed tomography of a patient examined for implant treatment planning.