“MR spectroscopy (MRS) and MR spectroscopic imaging (MRSI) for the non-invasive evaluation of glioblastoma multiform (GBM) tumors “ رسالة ماجستير

Abstract

Glioblastoma multiforme (GBM) is the most common and frequent tumor of the adult population's central nervous system, making up 40% of all brain tumor types and 15% to 20% of high-grade tumors. A critical public health issue, GBM is a rare tumor with a global incidence of less than 10 per 100,000 persons and a survival rate of 14–15 months after diagnosis. In all age categories, it accounts for 50% of all gliomas. A non-invasive imaging method called magnetic resonance spectroscopy (MRS) is used to examine metabolic alterations in brain malignancies. The current work used MRS multivoxel to investigate significant metabolites in GBM tumors. Since its first report in the 1980s, the human brain's magnetic resonance spectroscopy (MRS) has advanced quickly. Because it can be performed without requiring hardware modification on most MRI machines, unlike MRS of other nuclei, proton MRS became more and more popular in the 1990s because of its improved spatial localization and water suppression techniques as well as because of its increased sensitivity and convenience. An MRI scanner is utilized for the evaluation. Purpose of the study The purpose of this study is to evaluate and diagnose glioblastoma multiforme (GBM) using a non-invasive imaging method called magnetic resonance spectroscopy (MRS) to ability replace the biopsy to save the patient from having to undergo biopsy surgery and its associated hazard. XIII Methods of the study The study was a quantitative, cross-sectional, interventional study to evaluate the glioblastoma multiform using MR Spectroscopy and the effectiveness of the MRS to dispense with a biopsy in the MRI department work practice of Palestinian governmental hospitals, especially in Palestine Medical Complex (PMC) MRI department. From October 2022 to June 2023, data on 7 patients with GBM (2 patients new and 5 patients with tumor resection), 1 patient with metastatic disease, 1 patient with meningioma, and 1 patient with oligodendroglioma were gathered for this study. Utilizing a magnetic field strength of 1.5 Tesla and employing GE multivoxel Magnetic Resonance Spectroscopy (MRS), we conducted the Point-Resolved Spectroscopy (PRESS) procedure with an Echo Time (TE) of 144 ms and a Repetition Time (TR) of 1570 ms to acquire the data. Statistical analysis was subsequently applied to the extracted metabolites, including Pcho, NAA, Cr, Pcho/Cr ratio, Pcho/NAA ratio, NAA/Cho ratio, NAA/Cr ratio, and Cr/NAA ratio, to meticulously examine the spectroscopic data. Results For the total numbers of voxels of GBM, whether normal or tumoral, the level of metabolic ratio values of NAA/Cr, NAA/Pcho, Pcho /Cr, Pcho /NAA, and Cho concentration, were (1.24 ± 0.68, 0.90 ± 0.54, 1.81 ± 1.11,1.91 ± 2.08, 66999.17 ± 51226.74) respectively for the tumoral voxel and (2.34 ± 1.39, 1.67 ± 0.56, 1.49 ± 0.95, 0. 69 ± 0.34, 62585.15 ± 37676.36) respectively for normal XIV voxel, the ratio of the tumoral voxel were significantly higher than the normal ratio, and the concentration of Cho higher than the normal voxel. Conclusion The results of the current study showed that the most important and useful criteria for identifying tumoral and normal voxels in patients with glioblastoma who have 1HMRS are the NAA, Pcho/Cr, Cr/NAA, and Pcho/NAA ratios. However, due to the low sensitivity and specificity of the results, we cannot replace the diagnosis obtained through biopsy with MRS. Nevertheless, we can rely on MRS as a secondary diagnostic tool. The most accurate diagnostic test was Pcho/NAA, with a sensitivity of 83.3% and a specificity of 28.8%. Cr/NAA was the second efficient test (sensitivity: 78.2%, specificity: 35.6%). The Pcho/Crea Ratio was the third helpful test (sensitivity: 61.5%; specificity: 40.7%).