MR Spectroscopy Using Normalized and Non-normalized Metabolite Ratios for Differentiating Recurrent Brain Tumor from Radiation Injury
(2011) In Academic Radiology 18(9). p.1101-1108- Abstract
- Rationale and Objectives: To compare the ability of normalized versus non-normalized metabolite ratios to differentiate recurrent brain tumor from radiation injury using magnetic resonance spectroscopy (MRS) in previously treated patients. Materials and Methods: Twenty-five patients with previous diagnosis of primary intracranial neoplasm confirmed with biopsy/resection, previously treated with radiation therapy (range, 54-70 Gy) with or without chemotherapy and new contrast enhancing lesion on a 1.5 T magnetic resonance imaging at the site of the primary neoplasm participated in this retrospective study. After MRS, clinical, radiological, and histopathology data were used to classify new contrast-enhancing lesions as either recurrent... (More)
- Rationale and Objectives: To compare the ability of normalized versus non-normalized metabolite ratios to differentiate recurrent brain tumor from radiation injury using magnetic resonance spectroscopy (MRS) in previously treated patients. Materials and Methods: Twenty-five patients with previous diagnosis of primary intracranial neoplasm confirmed with biopsy/resection, previously treated with radiation therapy (range, 54-70 Gy) with or without chemotherapy and new contrast enhancing lesion on a 1.5 T magnetic resonance imaging at the site of the primary neoplasm participated in this retrospective study. After MRS, clinical, radiological, and histopathology data were used to classify new contrast-enhancing lesions as either recurrent neoplasm or radiation injury. Volume of interest included both the lesion and normal-appearing brain on the contralateral side. Non-normalized metabolic ratios were calculated from choline (Cho), creatine (Cr), and N-acetylaspartate (NAA) spectroscopic values obtained within the contrast-enhancing lesion: Cho/Cr, NAA/Cr, and Cho/NAA. Normalized ratios were calculated using the metabolic values from the contralateral normal side: Cho/normal creatinine (nCr), Cho/normal N-acetylaspartate (nNAA), Cho/normal choline, NAA/nNAA, NAA/nCr, and Cr/nCr. Results were correlated with the final diagnosis by Wilcoxon rank-sum analysis. Results: Two of three non-normalized ratios, Cho/NAA (sensitivity 86%, specificity 90%) and NAA/Cr (sensitivity 93%, specificity 70%) significantly associated with tumor recurrence even after correcting for multiple comparisons. Of the six normalized ratios, only Cho/nNAA significantly correlated with tumor recurrence (sensitivity 73%, specificity 40%), but did not remain significant after correcting for multiple comparisons. Conclusion: Cho/NAA and NAA/Cr were the two ratios with the best discriminating ability and both had better discriminating ability than their corresponding normalized ratios (Area under the curve = 0.92 versus 0.77, AUC= 0.85 vs. 0.66), respectively. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/2187312
- author
- Elias, Augusto E. ; Carlos, Ruth C. ; Smith, Ethan A. ; Frechtling, Dan ; George, Bekris ; Maly, Pavel LU and Sundgren, Pia LU
- organization
- publishing date
- 2011
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Brain tumors, magnetic resonance imaging, neoplasms, spectroscopy
- in
- Academic Radiology
- volume
- 18
- issue
- 9
- pages
- 1101 - 1108
- publisher
- Elsevier
- external identifiers
-
- wos:000294278800007
- scopus:79960972101
- ISSN
- 1878-4046
- DOI
- 10.1016/j.acra.2011.05.006
- language
- English
- LU publication?
- yes
- id
- 3c8f9217-9a96-4bf6-a290-838d5e10c251 (old id 2187312)
- date added to LUP
- 2016-04-01 13:25:23
- date last changed
- 2022-03-06 05:48:20
@article{3c8f9217-9a96-4bf6-a290-838d5e10c251, abstract = {{Rationale and Objectives: To compare the ability of normalized versus non-normalized metabolite ratios to differentiate recurrent brain tumor from radiation injury using magnetic resonance spectroscopy (MRS) in previously treated patients. Materials and Methods: Twenty-five patients with previous diagnosis of primary intracranial neoplasm confirmed with biopsy/resection, previously treated with radiation therapy (range, 54-70 Gy) with or without chemotherapy and new contrast enhancing lesion on a 1.5 T magnetic resonance imaging at the site of the primary neoplasm participated in this retrospective study. After MRS, clinical, radiological, and histopathology data were used to classify new contrast-enhancing lesions as either recurrent neoplasm or radiation injury. Volume of interest included both the lesion and normal-appearing brain on the contralateral side. Non-normalized metabolic ratios were calculated from choline (Cho), creatine (Cr), and N-acetylaspartate (NAA) spectroscopic values obtained within the contrast-enhancing lesion: Cho/Cr, NAA/Cr, and Cho/NAA. Normalized ratios were calculated using the metabolic values from the contralateral normal side: Cho/normal creatinine (nCr), Cho/normal N-acetylaspartate (nNAA), Cho/normal choline, NAA/nNAA, NAA/nCr, and Cr/nCr. Results were correlated with the final diagnosis by Wilcoxon rank-sum analysis. Results: Two of three non-normalized ratios, Cho/NAA (sensitivity 86%, specificity 90%) and NAA/Cr (sensitivity 93%, specificity 70%) significantly associated with tumor recurrence even after correcting for multiple comparisons. Of the six normalized ratios, only Cho/nNAA significantly correlated with tumor recurrence (sensitivity 73%, specificity 40%), but did not remain significant after correcting for multiple comparisons. Conclusion: Cho/NAA and NAA/Cr were the two ratios with the best discriminating ability and both had better discriminating ability than their corresponding normalized ratios (Area under the curve = 0.92 versus 0.77, AUC= 0.85 vs. 0.66), respectively.}}, author = {{Elias, Augusto E. and Carlos, Ruth C. and Smith, Ethan A. and Frechtling, Dan and George, Bekris and Maly, Pavel and Sundgren, Pia}}, issn = {{1878-4046}}, keywords = {{Brain tumors; magnetic resonance imaging; neoplasms; spectroscopy}}, language = {{eng}}, number = {{9}}, pages = {{1101--1108}}, publisher = {{Elsevier}}, series = {{Academic Radiology}}, title = {{MR Spectroscopy Using Normalized and Non-normalized Metabolite Ratios for Differentiating Recurrent Brain Tumor from Radiation Injury}}, url = {{http://dx.doi.org/10.1016/j.acra.2011.05.006}}, doi = {{10.1016/j.acra.2011.05.006}}, volume = {{18}}, year = {{2011}}, }