RATIONALE AND OBJECTIVES: The determination of tumor boundaries, especially in high-grade glioma, is critically important for the proper planning of treatment, but the standard diagnostic imaging methods do not enable precise delimitation of the extent of tumor cell infiltration into the surrounding tissue. The objective of this study was to assess the usefulness of hydrogen-1 (H-1) magnetic resonance (MR) spectroscopy for determining the extent of gliomatous infiltrate in the "uncertain zone'--the peritumoral area that appears unchanged on standard diagnostic MR images. MATERIALS AND METHODS: The study group consisted of 64 patients with cerebral glioma scheduled for tumor resection and subsequent radiation therapy. All patients were examined prior to resection with MR imaging and MR spectroscopy. MR spectra were obtained from examination of the solid part of the tumor and from two peritumoral volumes of interest located approximately along the axis of surgical access to the tumor. MR spectra obtained from a group of 32 healthy volunteers were used as control data. RESULTS: Analysis of the consequent voxels in the peritumoral zone revealed statistically significant differences in lipid/creatine and lactate/creatine metabolite ratios between patient subgroups with recurrent malignant lesions and without recurrent lesions. Significant differences also were found between the patient group and the control group in most metabolite ratios assessed. CONCLUSION: H-1 MR spectroscopic demonstration of metabolic changes in the peritumoral zone can guide treatment for cerebral glioma, enabling the physician to identify patients who have a high risk of recurrence.
RATIONALE AND OBJECTIVES: The determination of tumor boundaries, especially in high-grade glioma, is critically important for the proper planning of treatment, but the standard diagnostic imaging methods do not enable precise delimitation of the extent of tumor cell infiltration into the surrounding tissue. The objective of this study was to assess the usefulness of hydrogen-1 (H-1) magnetic resonance (MR) spectroscopy for determining the extent of gliomatous infiltrate in the "uncertain zone'--the peritumoral area that appears unchanged on standard diagnostic MR images. MATERIALS AND METHODS: The study group consisted of 64 patients with cerebral glioma scheduled for tumor resection and subsequent radiation therapy. All patients were examined prior to resection with MR imaging and MR spectroscopy. MR spectra were obtained from examination of the solid part of the tumor and from two peritumoral volumes of interest located approximately along the axis of surgical access to the tumor. MR spectra obtained from a group of 32 healthy volunteers were used as control data. RESULTS: Analysis of the consequent voxels in the peritumoral zone revealed statistically significant differences in lipid/creatine and lactate/creatine metabolite ratios between patient subgroups with recurrent malignant lesions and without recurrent lesions. Significant differences also were found between the patient group and the control group in most metabolite ratios assessed. CONCLUSION: H-1 MR spectroscopic demonstration of metabolic changes in the peritumoral zone can guide treatment for cerebral glioma, enabling the physician to identify patients who have a high risk of recurrence.
Authors: Ilwoo Park; Robert Bok; Tomoko Ozawa; Joanna J Phillips; C David James; Daniel B Vigneron; Sabrina M Ronen; Sarah J Nelson Journal: J Magn Reson Imaging Date: 2011-06 Impact factor: 4.813