Clinical Nuclear Medicine

Skip Navigation LinksHome > July 2013 - Volume 38 - Issue 7 > The Comparison of 13N-Ammonia and 18F-FDG in the Evaluation...
Clinical Nuclear Medicine:
doi: 10.1097/RLU.0b013e318295298d
Original Articles

The Comparison of 13N-Ammonia and 18F-FDG in the Evaluation of Untreated Gliomas

Shi, Xinchong MD; Liu, Yubo MD; Zhang, Xiangsong PhD; Yi, Chang MD; Wang, Xiaoyan MD; Chen, Zhifeng MD; Zhang, Bing MD

Collapse Box


Objective: Noninvasive evaluation of glioma is of great help for clinical practice. In this study, we investigated the utility of 13N-ammonia in the evaluation of untreated gliomas and compared the results with that of 18F-FDG.

Methods: Forty-five consecutive patients with final diagnosis of glioma were included in this study. PET/CT imaging was performed for all of them with both 18F-FDG and 13N-ammonia as tracers. Imaging results were analyzed by tumor-to-gray matter (T/G) ratios. Receiver operating characteristic curve analysis was conducted to determine the optimal T/G cutoff values of each tracer between low-grade and high-grade gliomas.

Results: Forty-eight separate lesions were identified in all (grade II, n = 16; grade III, n = 12; and grade IV, n = 20). Twenty-nine out of 32 high-grade lesions (91%) showed higher uptakes than normal gray matter with 13N-ammonia in comparison with the result of 21 lesions (66%) with 18F-FDG. The optimal T/G cutoff values for 18F-FDG and 13N-ammonia were 0.64 and 0.86 separately with the area under each curve 0.910 and 0.943. The sensitivity and specificity of predicting high-grade gliomas with optimal cutoff values were 83% and 93% for 18F-FDG and 94% and 94% for 13N-ammonia, respectively.

Conclusion: 13N-Ammonia is superior to 18F-FDG not only in separating low-grade gliomas from high-grade ones but also in the detection of high-grade gliomas for better tumor to normal gray matter contrast.

© 2013 by Lippincott Williams & Wilkins


Article Level Metrics

Search for Similar Articles
You may search for similar articles that contain these same keywords or you may modify the keyword list to augment your search.