Magnetic resonance spectroscopy and imaging on fresh human brain tumor biopsies at microscopic resolution

Abstract

[EN] The metabolic compn. and concn. knowledge provided by magnetic resonance spectroscopy (MRS) liq. and high-resoln. magic angle spinning spectroscopy (HR-MAS) has a relevant impact in clin. practice during magnetic resonance imaging (MRI) monitoring of human tumors. In addn., the combination of morphol. and chem. information by MRI and MRS has been particularly useful for diagnosis and prognosis of tumor evolution. MRI spatial resoln. reachable in human beings is limited for safety reasons and the demanding necessary conditions are only applicable on exptl. model animals. Nevertheless, MRS and MRI can be performed on human biopsies at high spatial resoln., enough to allow a direct correlation between the chem. information and the histol. features obsd. in such biopsies. Although HR-MAS is nowadays a well-established technique for spectroscopic anal. of tumor biopsies, with this approach just a mean metabolic profile of the whole sample can be obtained and thus the high histol. heterogeneity of some important tumors is mostly neglected. The value of metabolic HR-MAS data strongly depends on a wide statistical anal. and usually the microanatomical rationale for the correlation between histol. and spectroscopy is lost. We present here a different approach for the combined use of MRI and MRS on fresh human brain tumor biopsies with native contrast. This approach has been designed to achieve high spatial (18 × 18 × 50 m) and spectral (0.031 L) resoln. in order to obtain as much spatially detailed morphol. and metabolical information as possible without any previous treatment that can alter the sample. The preservation of native tissue conditions can provide information that can be translated to in vivo studies and addnl. opens the possibility of performing other techniques to obtain complementary information from the same sample.