Table 2.
Pupil responses to blue (470 nm) light and their correlations to lens transmission
| Parameter | Stimulus intensity cd/m2 | Mean | 95% CI |
Correlationto age |
Correlationto lens transmission |
||||
|---|---|---|---|---|---|---|---|---|---|
| b | R2 | p value | b | R2 | p value | ||||
|
LIGHT ON PARAMETERS | |||||||||
|
Maximal CA, % |
3 |
41.7 |
38.2–45.1 |
0.21 |
0.09 |
0.18 |
–0.17 |
0.08 |
0.34 |
| 30 |
48.4 |
46.0–50.9 |
0.19 |
0.07 |
0.10 |
–0.15 |
0.06 |
0.23 |
|
| 100 |
51.8 |
49.5–54.0 |
0.10 |
0.04 |
0.33 |
–0.02 |
0.01 |
0.89 |
|
| 300 |
55.3 |
53.4–57.3 |
0.16 |
0.09 |
0.07 |
–0.07 |
0.05 |
0.44 |
|
|
Sustained CA, % |
3 |
33.3 |
29.9–36.7 |
0.30 |
0.14 |
0.048* |
–0.21 |
0.09 |
0.22 |
| 30 |
44.6 |
42.4–46.9 |
0.17 |
0.10 |
0.09 |
–0.13 |
0.07 |
0.25 |
|
| 100 |
49.7 |
47.6–51.8 |
0.19 |
0.12 |
0.043* |
–0.12 |
0.06 |
0.22 |
|
| 300 |
52.5 |
50.4–54.5 |
0.23 |
0.15 |
0.014* |
–0.20 |
0.11 |
0.06 |
|
|
LIGHT OFF PARAMETERS | |||||||||
|
Early post-stim. AUC |
1.5 |
1.3–1.7 |
0.02 |
0.15 |
0.016* |
–0.01 |
0.06 |
0.21 |
|
| 30 |
2.1 |
1.9–2.2 |
0.01 |
0.08 |
0.09 |
–0.004 |
0.02 |
0.63 |
|
| 100 |
2.6 |
2.4–2.8 |
0.02 |
0.19 |
0.005* |
–0.01 |
0.08 |
0.22 |
|
| 300 |
3.1 |
2.9–3.3 |
0.03 |
0.29 |
0.0003* |
–0.03 |
0.18 |
0.02* |
|
| Late post-stim. AUC | 3 |
0.8 |
0.6–1.0 |
0.01 |
0.05 |
0.20 |
–0.002 |
0.02 |
0.88 |
| 30 |
1.2 |
0.9–1.5 |
0.008 |
0.04 |
0.56 |
0.009 |
0.04 |
0.60 |
|
| 100 |
1.8 |
1.4–2.3 |
0.02 |
0.05 |
0.30 |
0.009 |
0.06 |
0.69 |
|
| 300 | 2.8 | 2.4–3.3 | 0.04 | 0.08 | 0.07 | –0.03 | 0.04 | 0.29 | |
Each pupil response parameter is given as mean and its 95% confidence interval.
Correlations between pupil responses and age and between responses and lens transmission were calculated with adjustment for baseline pupil size and gender using a multiple linear regression model. Results are given as: b, the slope of the regression (response change per transmission unit), R2, the correlation coefficient, i.e., the fraction of variance explained by the regression model and the p-value.
For abbreviations and definitions of parameters, see Table 1 and Methods.
Blue (470 nm) light stimulus luminance of 300 cd/m2 corresponded to photon flux irradiance of 14.8 log photons/cm2/s.
* Level of significance p < 0.05. CI, confidence interval; b, slope of the regression; R2, correlation coefficient; CA, contraction amplitude; AUC, area under the curve.