Intraoperative fluorescein for improved tumor visualization in pediatric medulloblastoma surgery.

Background: The application of intraoperative fluorescein has emerged as a valuable technique to enhance tumor visualization during neuro-oncological procedures. Fluorescein sodium (FS) is a dye that accumulates in areas where the blood-brain barrier (BBB) is disrupted, with a major excitation wavelength peak ranging from 460 to 500 nm and a primary green emission peak between 540 and 690 nm. The intact BBB prevents FS uptake; however, the presence of a tumor can impair the BBB, allowing FS to accumulate within the tumor tissue. This provides enhanced visualization of the tumor. When administered intravenously, fluorescein selectively accumulates in tumor tissues, allowing surgeons to differentiate these areas from healthy brain tissue under a specialized fluorescence filter. This technique has the potential to improve resection accuracy and reduce the likelihood of residual tumor tissue. Case Description: This study presents the case of a 6-year-old patient diagnosed with medulloblastoma who underwent surgical resection with fluorescein guidance. The use of fluorescein enabled improved delineation of the tumor, facilitating a more precise resection. Postoperative magnetic resonance imaging confirmed complete removal of the lesion. This case supports the utility of fluorescein in pediatric brain tumor surgeries, particularly for achieving maximal safe resection, and underscores the potential benefits of incorporating fluorescein as an adjunct in pediatric neuro-oncological procedures. Conclusion: This case illustrates an effective and safe alternative using a fluorescent technique with FS in the pediatric population. Fluorescein is a valuable tool in the surgical management of medulloblastoma, aiding in the visualization and resection of the tumor.