Table 1:

Threshold values for multiple parameters for differentiating high- and low-grade gliomas

Parameters	Based on Minimum C1 Error					Errors		Based on Minimum C2 Error					Errors
	Threshold	Sensitivity	Specificity	PPV	NPV	C1	C2	Threshold	Sensitivity	Specificity	PPV	NPV	C1	C2
rCBF ratio mean	2.562	0.652	0.778	0.882	0.467	0.285	0.170	2.562	0.652	0.778	0.882	0.467	0.285	0.170
rCBF ratio max	2.845	0.609	0.778	0.875	0.438	0.307	0.202	2.845	0.609	0.778	0.875	0.438	0.307	0.202
rCBF ratio min	2.017	0.739	0.667	0.850	0.500	0.297	0.179	2.017	0.739	0.667	0.850	0.500	0.297	0.179
rCBF ratio meana	1.800	0.824	0.667	0.933	0.401	0.255	0.142	1.800	0.824	0.667	0.933	0.401	0.255	0.142
rCBF ratio maxa	2.258	0.765	0.667	0.929	0.334	0.284	0.166	2.258	0.765	0.667	0.929	0.334	0.284	0.166
rCBF ratio mina	1.254	0.882	0.667	0.938	0.499	0.226	0.125	1.254	0.882	0.667	0.938	0.499	0.226	0.125
FA ratio mean	0.236	0.870	0.556	0.834	0.626	0.287	0.214	0.267	0.739	0.667	0.850	0.500	0.297	0.179
FA ratio max	0.288	0.870	0.667	0.870	0.668	0.232	0.128	0.288	0.870	0.667	0.870	0.668	0.232	0.128
FA ratio min	0.279	0.565	0.667	0.813	0.375	0.384	0.300	0.279	0.565	0.667	0.813	0.375	0.384	0.300
ADC ratio mean	1.659	0.913	0.667	0.875	0.750	0.210	0.118	1.659	0.913	0.667	0.875	0.750	0.210	0.118
ADC ratio max	1.538	0.826	0.556	0.826	0.556	0.309	0.227	1.538	0.826	0.556	0.826	0.556	0.309	0.227
ADC ratio min	1.564	0.913	0.667	0.875	0.750	0.210	0.118	1.564	0.913	0.667	0.875	0.750	0.210	0.118
Cho/Cr	1.789	0.913	0.778	0.913	0.778	0.155	0.057	1.789	0.913	0.778	0.913	0.778	0.155	0.057
NAA/Cho	0.349	0.696	0.778	0.889	0.500	0.263	0.142	0.349	0.696	0.778	0.889	0.500	0.263	0.142
NAA/Cr	1.289	0.304	1.000	1.000	0.360	0.348	0.484	0.894	0.478	0.778	0.846	0.368	0.372	0.322
Lac/Cr	1.789	0.739	1.000	1.000	0.600	0.131	0.068	1.789	0.739	1.000	1.000	0.600	0.131	0.068

Note:—min indicates minimum; max, maximum.

^arCBF ratios derived from purely astrocytomas.