Autofluorescence of normal and neoplastic human brain tissue: an aid for intraoperative delineation of tumor resection margins

Light-induced autofluorescence measurements were made on normal and tumor brain tissues to assess their spectroscopic properties and to verify the potential of this parameter for an intraoperative delineation of tumor resection margins. Spectrofluorometric analysis was performed both at the microscope on tissue sections from surgical resection, and on patients affected by glioblastoma, during surgical operation. Significant differences in autofluorescence emission properties were found between normal and tumor tissues in both ex vivo and in vivo measurements, indicating that the lesion can be distinguished from the normal surrounding tissues (white matter and cortex) by the signal amplitude and the spectral shape. The non-invasiveness of the technique opens interesting prospects for improving the efficacy of neurosurgical operation, by allowing an intraoperative delimitation of tumor resection margins.