Role of MR Spectroscopy in the diagnosis of brain masses and comparison of Long and Short TE MR Spectroscopy

Abstract

Introduction: We aimed to evaluate the value of long and short TE MR spectroscopy in the diagnosis of intracranial mass lesions. Methods: Fifty patients with intracranial mass lesions were evaluated with long and short TE MR spectroscopy, and findings were compared with postsurgical pathological results. Results: All glial tumors showed decrease in NAA and prominent increase in Cho levels. High grade glial tumors revealed high Cho/Cr and Cho/NAA in both long and short TE, and low NAA/Cr in long TE acquisitions. Among 8 high grade gliomas, 7 had lipid peaks at 0,9ppm, 1 had lipid peak at 1,3 ppm, 4 had lipid-lactate peaks at 1,3ppm, 3 had high ml/GL, and 3 had high Glx. Two patients with high grade gliomas showed lipid peaks and 4 showed lactate peaks at long TE spectrums. Among 15 patients with metastases, NAA and Cr peaks were not detected in 9 short TE and 7 long TE spectrums. All meningiomas showed Cho İncrease, while 9 of 10 meningioma lesions showed no prominent NAA peak. Among 5 medulloblastomas, 4 showed decrease in NAA and Cr, and increase in Cho at short and long TE spectrums. Conclusion: It should be considered that long and short TE MR Spectroscopy reveal complementary knowledge to each other in determination of intracranial mass lesions, and both should be acquired if possible.