Brain tissue autofluorescence: an aid for intraoperative delineation of tumor resection margins

The intrinsic autofluorescence properties of biological tissues can change depending on alterations induced by pathological processes. Evidence has been reported concerning the application of autofluorescence as a parameter for in situ cancer detection in several organs. In this paper, autofluorescence properties of normal and tumor tissue in the brain are described, suitable for a real-time diagnostic application. Data were obtained both on ex vivo resected samples, by microspectrofluorometric techniques, and in vivo, during surgical operation, by means of fiberoptic probe. Significant differences were found in autofluorescence emission properties between normal and tumor tissues, in terms of both spectral shape and signal amplitude, that confirm the potential of autofluorescence as a parameter to distinguish neoplastic from normal condition. The noninvasiveness of the technique opens up interesting prospects for improving the efficacy of neurosurgical operations, by allowing an intraoperative delineation of tumor resection margins.