Vertebral pneumatocysts are gas-filled cavities within the spinal vertebrae. They are most common at cervical levels. In general, vertebral pneumatocysts are less common than intraosseous pneumatocysts in the pelvis, especially adjacent to the sacroiliac joint.
Although not completely understood, some authors believe a vertebral pneumatocyst is an extension of intradiscal gas (vacuum phenomenon) 1. On follow up, these lesions can change into fluid-filled cavities and eventually become granulation tissue 2. Lesions can enlarge in size 1.
Difficult to detect, but sometimes gas lucencies are seen within the vertebral bodies.
Considered the best method of diagnosis. Gas measures about -580 to -1000 HU in density 3. Detection of associated intradiscal gas and communication between the vertebral and intradiscal gas can be demonstrated. Epidural extension may also be detected.
Appearances on MRI are less definitive than on CT. Gas appears as low signal/signal void on both T1 and T2, and so appears similar to sclerotic bone.
Treatment and prognosis
This may be followed up to detect any increase in the size, but there is no specific treatment.
- Kümmell disease
- vertebral osteomyelitis
- tumor with necrosis
- sclerotic bone lesion (on MRI)
- 1. Kitagawa T, Fujiwara A, Tamai K et-al. Enlarging vertebral body pneumatocysts in the cervical spine. AJNR Am J Neuroradiol. 2004;24 (8): 1707-10. Pubmed citation
- 2. Yamamoto T, Yoshiya S, Kurosaka M et-al. Natural course of an intraosseous pneumatocyst of the cervical spine. AJR Am J Roentgenol. 2002;179 (3): 667-9. doi:10.2214/ajr.179.3.1790667 - Pubmed citation
- 3. Haithcock JA, Layton KF, Opatowsky MJ. Vertebral pneumatocysts: uncommon lesions with pathognomonic imaging characteristics. (2006) Proceedings (Baylor University. Medical Center). 19 (4): 423-4. Pubmed