Sarcoidosis of the Spine¶

Definition¶

Sarcoidosis is a systemic granulomatous disease of unknown etiology that rarely involves the spine. When it does, it can affect the vertebral bodies, spinal cord (neurosarcoidosis), leptomeninges, or nerve roots. Spinal sarcoidosis is a diagnostic challenge because it can mimic metastatic disease, lymphoma, or infection.

Imaging Findings¶

Vertebral Sarcoidosis¶

Radiography/CT — Lytic, sclerotic, or mixed lytic-sclerotic vertebral body lesions. May show cortical destruction or trabecular coarsening.
MRI — Low T1, variable T2 signal in vertebral body lesions with enhancement. Can mimic metastasis.

Neurosarcoidosis (Spinal Cord)¶

MRI — Intramedullary lesion with cord expansion, T2 hyperintensity, and enhancement. The enhancement may be nodular, linear, or diffuse. Can extend over multiple segments.
May show leptomeningeal enhancement (coating the cord surface)
Dorsal subpial enhancement is considered relatively characteristic

Leptomeningeal Sarcoidosis¶

Diffuse or nodular enhancement of the leptomeninges on post-contrast MRI
Can mimic leptomeningeal carcinomatosis or infectious meningitis

Clinical Pearl

Spinal sarcoidosis has no pathognomonic imaging findings — it is a great mimic. The diagnosis is usually made by combining imaging findings with systemic evidence of sarcoidosis (bilateral hilar lymphadenopathy on chest imaging, elevated ACE, non-caseating granulomas on biopsy). When you see an intramedullary cord lesion or leptomeningeal enhancement in a patient with known pulmonary sarcoidosis, neurosarcoidosis should be considered.

Key Points¶

Sarcoidosis rarely involves the spine but can affect vertebrae, cord, and leptomeninges
Vertebral lesions can mimic metastasis; cord lesions can mimic tumor or demyelination
Leptomeningeal enhancement can mimic carcinomatosis
Diagnosis requires clinical correlation with systemic sarcoidosis findings
Biopsy showing non-caseating granulomas is definitive

References¶

Smith JK, Matheus MG, Castillo M. Imaging manifestations of neurosarcoidosis. AJR Am J Roentgenol. 2004;182(2):289-95. https://pubmed.ncbi.nlm.nih.gov/14736648/
Shah R, Roberson GH, Curé JK. Correlation of MR imaging findings and clinical manifestations in neurosarcoidosis. AJNR Am J Neuroradiol. 2009;30(5):953-61. https://pubmed.ncbi.nlm.nih.gov/19193748/
Zalewski NL, Krecke KN, Weinshenker BG, et al. Central canal enhancement and the trident sign in spinal cord sarcoidosis. Neurology. 2016;87(7):743-4. https://pubmed.ncbi.nlm.nih.gov/27527540/
Murphy OC, Salazar-Camelo A, Jimenez JA, et al. Clinical and MRI phenotypes of sarcoidosis-associated myelopathy. Neurol Neuroimmunol Neuroinflamm. 2020;7(4):e722. https://pubmed.ncbi.nlm.nih.gov/32269072/
Poyanli A, Poyanli O, Sencer S, et al. Vertebral sarcoidosis: imaging findings. Eur Radiol. 2000;10(1):92-94. https://pubmed.ncbi.nlm.nih.gov/10663722/
Pirau L, Lui F. Neurosarcoidosis. In: StatPearls. Treasure Island (FL): StatPearls Publishing; updated 2023 Jul 3. https://www.ncbi.nlm.nih.gov/books/NBK534768/
Neurosarcoidosis. Radiopaedia.org. https://radiopaedia.org/articles/neurosarcoidosis