Diagnostic Potential of Autofluorescence for an Assisted Intraoperative Delineation of Glioblastoma Resection Margins¶

Abstract

The intrinsic autofluorescence properties of biological tissues can be affected by the occurrence of histological and biochemical alterations induced by pathological processes. In this study the potential of autofluorescence to distinguish tumor from normal tissues was investigated with the view of a real-time diagnostic application in neurosurgery to delineate glioblastoma resection margins. The autofluorescence properties of nonneoplastic and neoplastic tissues were analyzed on tissue sections and homogenates by means of a microspectrofluorometer, and directly on patients affected by glioblastoma multiforme, during surgery, with a fiber-optic probe. Scan-microspectrofluorometric analysis on tissue sections evidenced a reduction of emission intensity and a broadening of the main emission band, along with a redshift of the peak position, from peritumoral nonneoplastic to neoplastic tissues. Differences in both spectral shape and signal amplitude were found in patients when the glioblastoma lesion autofluorescence was compared with those of cortex and white matter taken as healthy tissues. Both biochemical composition and histological organization contribute to modify the autofluorescence emission of neoplastic, with respect to nonneoplastic, brain tissues. The differences found in the in vivo analysis confirm the prospects for improving the efficacy of tumor resection margin delineation in neurosurgery.

405 nm versus 633 nm for protoporphyrin IX excitation in fluorescence‐guided stereotactic biopsy of brain tumors

“…Additionally, a broad and characteristic emission spectrum is induced, allowing the extraction of valuable spectral information. [46,47] Moreover, the use of a 405 nm light source also leads to the excitation of tissue autofluorescence, which could be used as an additional parameter for tissue discrimination [48][49][50] or serve as reference for the normalization of PpIX signals [27].…”

Fluorescence Lifetime Spectroscopy in Cardioand Neuroimaging

“…These include studies of glioblastoma [88][89][90][91][92][93], astrocytoma, oligodendroglioma, and metastatic carcinoma [90]. For example, combining fluorescence (excitation 337 nm) with diffuse reflectance spectroscopy at multiple excitation wavelengths [90] or using microspectrofluorometric measurements at a few excitation wavelengths [89], it has been shown that brain tumors can be distinguished from normal brain tissue with good sensitivity and specificity. Previously, the Marcu et al research group reported results on the time-resolved fluorescence of glioblastoma [92,93] and meningioma [94].…”

“…Subsequently, Croce et al [89] used a similar method to analyze the autofluorescence properties of nonneoplastic and neoplastic tissues, those of homogenates by means of a microspectrofluorometer, and directly on patients affected by glioblastoma multiforme, during surgery, with a fiber optic probe. Fluorescence spectra of supernatants of both tumor and nonneoplastic tissue homogenates were excited using 366 and 405 nm.…”

Autofluorescence properties of rat cerebellum cortex during postnatal development

“…The samples were preserved at À808C until mounted for cryostatic sectioning (30-mm thickness). Tissue sections were submitted to measurements, according to a procedure already described, ensuring a reliable preservation of the autofluorescence properties of the in vivo condition [32].…”