Table 3.

¹³N-NH₃, ¹¹C-MET and ¹⁸F-FDG uptake positive in all lesion groups and mean L/WM ratios in neoplastic lesions, LGG, HGG and NNL

Group	No. of Patients	Positive, n			L/WM (mean ± SD)
		NH3	MET	FDG	NH3	MET	FDG
Neoplastic lesions	67	42	63	24	2.25 ± 0.69	2.96 ± 0.95	2.00 ± 0.86
LGG	27	6	24	1	1.76 ± 0.51	2.34 ± 0.56	1.36 ± 0.35
HGG	30	27	30	18	2.59 ± 0.54	3.64 ± 0.90	2.59 ± 0.75
Non-glioma tumors	10	9	9	5
NNL	23	1	10	8	1.50 ± 0.27	1.88 ± 0.63	2.07 ± 0.71

LGG low-grade glioma, HGG high-grade glioma, NNL non-neoplastic lesions, L/WM Lesion-to-white matter ratio