DIAGNOSTIC ACCURACY OF MRS BRAIN FOR GLIAL TUMORS AND ITS GRADING KEEPING HISTOPATHOLOGY AS A GOLD STANDARD

Abstract

Objectives: To determine the Diagnostic accuracy of MRS brain for Glial tumors and its grading keeping histopathology as a gold standard.

Materials and Methods: This cross-sectional study, approved by the hospital's ethical board and research committee, included patients who met the inclusion criteria and provided informed consent. The study's purpose, benefits, and confidentiality were explained, with assurance that participation would not affect future care. All participants underwent MRS using a standardized 1.5T MRI protocol. Tumors were assessed according to WHO histopathological standards. Key metabolic markers, such as NAA, Choline, Lipids, Lactate, and Myo-inositol, were analyzed using MRS for diagnosing and grading glial tumors, with grading based on standard criteria like the Choline/NAA ratio for high-grade gliomas. Tumor specimens were obtained via biopsy or surgical resection, and histopathological examination confirmed tumor presence and grade. Data was collected using a predesigned questionnaire and analyzed using SPSS version 25.

Results: The mean age of participants was 52.18 ± 12.19 years, with 18.3% between 18–40 years, 54.9% between 41–60 years, and 26.8% over 60 years. The gender distribution was 52.4% male and 47.6% female. Low-grade tumors included oligodendrogliomas (11.0%) and astrocytomas (14.6%), while high-grade tumors consisted of anaplastic astrocytomas (11.0%), anaplastic oligoastrocytomas (4.9%), and glioblastomas (58.5%). The Cho/Cr ratio in low-grade tumors was 1.692 ± 0.40, while in high-grade tumors it was elevated at 2.489 ± 0.65. The NAA/Cr ratio was 1.578 ± 0.40 for low-grade and 0.642 ± 0.26 for high-grade tumors. The Cho/Cr ratio demonstrated strong diagnostic performance, with sensitivity of 77.0%, specificity of 85.7%, PPV of 86.9%, NPV of 75.0%, and overall accuracy of 82.9%.

Conclusion: MRS is a valuable tool for detecting and grading glial tumors, providing a non­invasive alternative to histopathology with notable diagnostic accuracy. While it may not replace histopathology entirely, MRS can complement clinical practice for initial tumor assessment,

treatment monitoring, and non-invasive glioma grading. Future research is needed to confirm these findings and further define MRS’s role in managing glial tumors.