Sodium fluorescein-guided resection of an intramedullary spinal cord clear cell meningioma: illustrative case.

BACKGROUND: An intramedullary spinal cord clear cell meningioma (CCM) is an exceptionally rare diagnosis; there are only 2 similar cases reported in the literature. The authors present a case of an intramedullary spinal cord CCM that was successfully resected with the assistance of sodium fluorescein to guide resection. OBSERVATIONS: A 68-year-old male presented with gait instability, decreased sensation, and loss of proprioception in the lower extremities, concerning for thoracic myelopathy. MRI of the thoracic spine revealed an intradural, intramedullary contrast-enhancing mass most concerning for a spinal ependymoma or astrocytoma. Given his progressive neurological decline, need for tissue diagnosis, and tumor cytoreduction, fluorescence-guided resection of the mass was performed. Postoperative pathological analysis demonstrated the presence of polygonal tumor cells with clear cytoplasm that harbored a known pathogenic SMARCE1 frameshift mutation that supported the diagnosis of an intramedullary CCM. LESSONS: The authors present the first reported case of a fluorescence-guided resection of an intramedullary CCM. https://thejns.org/doi/10.3171/CASE251031.