Table 3.
Semi-quantitative parameters derived on N-13 ammonia positron emission computed tomography-computed tomography and Tc-99m glucoheptonate single photon emission computed tomography-computed tomography with respect to the reference standard
| Parameter | Reference standard | Pa | |
|---|---|---|---|
| Recurrence | No recurrence | ||
| N-13 NH3 PET-CT | |||
| T/W | 2.89±1.91 (2.70, 0.27-8.86) | 1.15±0.98 (0.68, 0.21-4.46) | <0.001 |
| T/G | 1.29±0.74 (1.37, 0.10-2.82) | 0.46±0.36 (0.38, 0.06-1.65) | <0.001 |
| Tc-99m GHA SPECT-CT | |||
| T/N | 11.70±7.72 (11.75, 0.43-27.00) | 3.76±4.34 (2.46, 0.79-20.31) | <0.001 |
| T/S | 0.97±0.62 (0.94, 0.07-2.61) | 0.29±0.39 (0.15, 0.04-1.72) | <0.001 |
| T/NPX | 1.06±0.60 (1.13, 0.06-2.13) | 0.39±0.54 (0.21, 0.05-2.07) | <0.001 |
Data are presented as mean±SD (median, range). aP value derived on Mann-Whitney U-test. CPP: Counts per pixel, SUVmax; Standardized uptake value maximum, T/W: Tumor to white matter SUVmax ratio, T/G: Tumor to grey matter SUVmax ratio, T/N: Tumor to normal CPP ration, T/S: Tumor to scalp CPP ratio, T/NPX: Tumor to nasopharynx CPP ratio as described in the text under materials and methods section, Tc-99m GHA SPECT-CT: Tc-99m glucoheptonate single photon emission computed tomography-computed tomography, N-13NH3 PET-CT: N-13 ammonia positron emission computed tomography-computed tomography, SD: Standard deviation