[Side differences in the position of the corneal apex in relation to the lateral orbital margin (measurements with the Hertel exophthalmometer)].

Proptosis was measured with Hertel's apparatus in 430 persons ranging in age from 3 to over 60 years. They were divided into 12 age groups for males and 12 for females. Measurements were performed independently by two investigators. The average of all readings shows the left eye in males 0.49 mm in front of the right eye. In females the difference is 0.52 mm (males: right eye 15.25 mm, left eye 15.74 mm; females: r.e. 14.79 mm, l.e. 15.31 mm). From the third to the 20th year of life there is a permanent increase in proptosis from about 13.0 to about 16.7 mm. There are no major differences between males and females. After the 20th year, males show a small increase up to 17.0 mm. In females the readings drop to about 15.6 mm. Lefthandedness in young people is found in 13.6% of males and in 5.7% of females.