Interpupillary index: a new parameter for hypo-hypertelorism

J Craniomaxillofac Surg. 2001 Aug;29(4):191-4. doi: 10.1054/jcms.2001.0230.


Aim: To establish a new clinical index to evaluate the presence of hypo-hypertelorism with greater accuracy.

Material and methods: After screening a wide range of population, 310 elementary school children (185 boys, 125 girls) aged 7-15 years were included in this study. For this cross-sectional study, a millimetre ruler was used. The anatomical interpupillary distance was measured by a modified Viktorin's method. In addition, inner and outer intercanthal distances were obtained. The data were analyzed by Student's t-test for two independent samples using SPSS for Windows. There were children with clinical hypertelorism (n = 92, group 1), children with large fronto-occipital circumference (FOC) (n = 101, group 2), and age- and sex-matched normal controls (n = 117, group 3). Due to variations in FOC among healthy subjects, we introduced a new practical concept for evaluation of interpupillary distance, namely the interpupillary index, the simple product obtained by dividing the interpupillary distance by the FOC, multiplied by 100.

Results: The overall idiopathic benign macrocephalic children (group 2) had significantly (p < 0.001) larger interpupillary distances (6.13 +/- 0.36 cm) and FOCs (56.99 +/- 1.46 cm) than those of normal controls (5.70 +/- 0.26cm and 52.82 +/- 1.22 cm, respectively). But, the difference between the combined product of interpupillary distance and FOC, the interpupillary index, was not significant (10.76 +/- 0.50 and 10.79 +/- 0.35, respectively) (p > 0.05). On the other hand, the children with hypertelorism had significantly (p < 0.001) larger interpupillary distances (6.47 +/- 0.29cm) and FOCs (54.90 +/- 2.18cm) when compared with the controls. In addition, the interpupillary index was significantly (p < 0.001) higher (11.80 +/- 0.45) than both macrocephalic children (10.76 +/- 0.50) and controls (10.79 +/- 0.35). Intercanthal distances and intercanthal index of hyperteloric children were also significantly (p<0.001) larger than both macrocephalic children and controls.

Conclusion: This new index offers a new concept for more accurate evaluation of the presence of ocular hypo-hypertelorism.

Publication types

  • Case Reports

MeSH terms

  • Adolescent
  • Case-Control Studies
  • Cephalometry / standards*
  • Child
  • Eye / anatomy & histology
  • Forehead / anatomy & histology
  • Humans
  • Hypertelorism / diagnosis*
  • Hypertelorism / pathology
  • Male
  • Reference Values
  • Skull / anatomy & histology