In an attempt to understand the underlying developmental causes of facial asymmetry, the spring 1998 Comparative Anatomy class collected data from volunteers ranging in age from 18 to 61. We used a ruler to measure the distance between the center of the bridge of the nose and the center of the pupil and between the center of the bridge of the nose and the lateral edge of the orbit. The data are presented below.
| Table 1. Distance between the birdge of the nose and the left pupil (Lpupil), bridge of the nose and right pupil (Rpupil), bridge of the nose and left orbit (Lorbit), and bridge of the nose and right orbit (Rorbit). Key: Sex, 1=male and 2=female; Sightedenes, 1=normal, 2=near, 3=far, 4=astigmatism, and 5=other; Eye Dominance, 1=right, 2=left. | |||||||||
| Participant Number | Sex | Age | Sightedness | Handedness | Eye Dominance | Lpupil (mm) | Rpupil (mm) | Lorbit (mm) | Rorbit (mm) |
| 3129801 | 1 | 58 | 2 | 2 | 1 | 37 | 37 | 56 | 57 |
| 3129802 | 1 | 59 | 4 | 1 | 1 | 35 | 35 | 57 | 56 |
| 3129803 | 1 | 52 | 2 | 2 | 2 | 32 | 30 | 48 | 46 |
| 3129804 | 2 | 47 | 3 | 1 | 1 | 34 | 31 | 50 | 49 |
| 3129805 | 2 | 21 | 2 | 1 | 2 | 27 | 29 | 49 | 50 |
| 3129806 | 2 | 61 | 4 | 1 | 2 | 37 | 35 | 57 | 55 |
| 3129807 | 1 | 33 | 1 | 2 | 2 | 35 | 35 | 58 | 56 |
| 3129808 | 2 | 35 | 2 | 1 | 2 | 32 | 30 | 54 | 56 |
| 3129811 | 2 | 18 | 2 | 1 | 2 | 31 | 29 | 50 | 50 |
| 3129812 | 1 | 36 | 2 | 2 | 1 | 35 | 35 | 55 | 60 |
| 3129813 | 1 | 20 | 1 | 1 | 1 | 30 | 34 | 48 | 49 |
| 3129814 | 1 | 19 | 1 | 1 | 1 | 33 | 33 | 54 | 54 |
| 3129815 | 2 | 21 | 5 | 1 | 1 | 32 | 31 | 53 | 52 |
| 3129816 | 2 | 19 | 2 | 1 | 2 | 29 | 28 | 46 | 47 |
| 3129817 | 1 | 21 | 1 | 1 | 1 | 33.5 | 36.5 | 55 | 54 |
| 3129818 | 1 | 20 | 2 | 1 | 1 | 31 | 32 | 51 | 51 |
| 3129819 | 1 | 19 | 2 | 1 | 1 | 30.5 | 33.5 | 49.5 | 51.5 |
| 3129820 | 1 | 21 | 2 | 1 | 2 | 32 | 31 | 57 | 54 |
| 3129821 | 1 | 25 | 1 | 1 | 2 | 37 | 34.5 | 53 | 54 |
| 3129822 | 2 | 20 | 2 | 1 | 2 | 28 | 26 | 50 | 52 |
| 3129823 | 1 | 24 | 1 | 1 | 1 | 31 | 34 | 54 | 55 |
| 3129824 | 1 | 43 | 4 | 1 | 1 | 33.2 | 30.1 | 51.8 | 48.8 |
| 3129825 | 2 | 21 | 2 | 1 | 1 | 29.5 | 29 | 48 | 46 |
| 3129826 | 1 | 45 | 1 | 1 | 3 | 35 | 35 | 56 | 55 |
| 3129827 | 2 | 18 | 1 | 1 | 1 | 35 | 35 | 55 | 55 |
| 3129828 | 2 | 42 | 4 | 1 | 1 | 33 | 31 | 53 | 52 |
| 3129829 | 2 | 34 | 4 | 1 | 1 | 34 | 34 | 56 | 55 |
| 3129830 | 1 | 19 | 1 | 1 | 1 | 29 | 30 | 50 | 49 |
| 3129831 | 1 | 18 | 1 | 1 | 2 | 32 | 34.5 | 50 | 52.1 |
| 3129832 | 2 | 19 | 2 | 1 | 1 | 30.5 | 32 | 50.2 | 51 |
| 3129833 | 2 | 39 | 1 | 1 | 2 | 32 | 34 | 55.5 | 55 |
| 3129834 | 2 | 31 | 2 | 1 | 1 | 35 | 34 | 50 | 52 |
The above data table is also available as a comma delimited text file or as a downloadable MS Excel xls file.
The above data were analyzed through use of JMP Statistical Discovery Software from SAS. A two-tailed t-test revealed that the average difference between the right pupil and the center of the bridge of the nose and the left pupil and the center of the bridge of the nose in this sample was not significantly different from zero (t-statistic = -0.193, p = 0.848 for a two-tailed test, N = 32). There were also no significant differences when the right and left orbit distances were compared (t-statistic=-0.061, p=0.952). A regression analysis using age as the dependent variable and the difference between right and left orbit distances showed no significant trend. However, Figure 1 demonstrates a significant negative relationship between age and right-left pupil difference (right-left pupil = 1.638 - 0.035 Age, R Squared=0.159, ANOVA F Ratio = 5.68, P > F = 0.024, N = 32).
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| Figure 1. Relationship between age and difference between right pupil distance and left pupil distance and confidence intervals. |
A t-test of the average right-left pupil difference among 18-29 year-olds revealed no significant difference from zero (t-statistic = 1.294, p = 0.213, N = 18). However, the left pupil distance was significantly greater than the right pupil distance in those individuals 30 years and older (t-statistic = -2.414, p = 0.03, N = 14).
Contingency table analysis revealed no significant relationship between handedness and eye dominace (X2 = 0.121, p = 0.73, N = 31), nor between handedness and right-left orbit distance difference (X2 = 0.164, p = 0.685, N = 32). However, a significant positive relationship was observed between handedness and right-left pupil distance difference (X2 = 3.251, p = 0.07, N = 32).
Last updated 4/4/00
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