Detection of meningioma in dura mater by Raman spectroscopy

Radical tumor resection is the treatment of choice for patients suffering from meningioma. However, recurrence of these tumors is a problem. Tumor recurrences are attributed to residual nests of meningioma within the regional dura. Therefore, complete removal of all tumor-infiltrated dura is important. Meningioma and normal dura were studied by Raman microspectroscopy to assess the possibility of developing an in vivo Raman method for guidance of meningioma resections. Pseudocolor Raman maps were constructed of cryosections of dura and meningioma, obtained from 20 patients. Comparison of these maps with histopathology enabled assignment of the spectra to either meningioma or dura. Large differences exist between the Raman spectra of dura and meningioma, because of the high collagen content of dura and the increased lipid content of tumors. A classification model for dura and tumor tissue based on linear discriminant analysis of Raman spectra yielded an accuracy of 100%. A first attempt was made to determine the minimum amount of meningioma in dura that is detectable by Raman spectroscopy. It is concluded that Raman spectra enable meningioma to be distinguished from dura, which makes Raman spectroscopy a viable candidate for guidance of surgical resection of meningioma.