Results of laser induced fluorescence
| Excitation wavelength | ALA/non-ALA | Sensitivity | Specificity | PPV | NPV | p Value |
|---|---|---|---|---|---|---|
| 337 nm | ALA+non-ALA | 13/13 (100%) | 26/27 (96%) | 13/14 (93%) | 26/26 (100%) | <0.001 |
| 405 nm | Non-ALA | 1/5 (20%) | 9/11 (82%) | 1/3 (33%) | 9/13 (69%) | 0.2 |
| 405 nm | ALA | 8/9 (89%) | 16/17 (94%) | 8/9 (89%) | 16/17 (94%) | <0.001 |
| 436 nm | Non-ALA | 2/4 (50%) | 12/14 (86%) | 2/4 (50%) | 12/14 (86%) | 0.07 |
| 436 nm | ALA | 6/7 (86%) | 16/16 (100%) | 6/6 (100%) | 16/17 (94%) | 0.002 |
All values are based on the assumption that the threshold between neoplasia and non-neoplasia is at a LIF score of 0. In thet test, the tested hypothesis is that the LIF scores from adenomatous spectra have a lower mean value than the scores from normal tissue spectra. The p value denotes the level of significance below which this hypothesis was found to be true.
PPV, positive predictive value; NPV, negative predictive value.