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 Tools


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.