Use of intraoperative sodium fluorescein for diagnostic tissue biopsy of spinal cord lesions

Background: Recent evidence suggests that fluorescein-guided microsurgery facilitates resection of intrinsic and metastatic lesions in the brain. Use of sodium fluorescein for angiography has previously been reported without non-specific diffusion into the adjacent spinal parenchyma. Diagnostic biopsy of spinal cord lesion is often challenging and the localization of such lesions intraoperatively is paramount. We present the first known report of use of sodium fluorescein for localization and diagnostic biopsy of intrinsic spinal cord lesions. Methods: Three patients with spinal cord lesions received fluorescein sodium 10% (Alcon Laboratories INC, Fort Worth, TX, USA) at 3 mg/kg prior to surgical resection. Intraoperative visualization of fluorescence was performed using a Zeiss Pentero (Carl Zeiss AG, Oberkochen, Germany) microscope equipped with a Yellow560 filter or a Leica OH6 (Leice Microsystems, Wetzlar, Germany) equipped with a FL560 filter. Results: Administration of sodium fluorescein resulted in lesional fluorescent contrast extravasation and facilitated surgical resection. The addition of sodium fluorescein allowed for identification and facilitated biopsy in three patients. In patients undergoing biopsy, tissue samples were positive for a diagnostic pathology. Conclusion: Fluorescein may be a helpful microsurgical tool in guiding resection and localization for tissue biopsy of intramedullary spinal lesions. Further research is necessary to explore fluorescein sodium applications in the resection of spinal cord lesions.