Exophthalmometric value and palpebral fissure dimension in an African population

Abstract

Background: Normative data for exophthalmometric values and palpebral fissure dimensions are important for earlier diagnosis of orbital and palpebral fissure pathologies. Objective: To describe the normal exophthalmometric values and palpebral fissure dimensions among healthy adults of Black race. Design: A cross-sectional descriptive study. Setting: Population based (general community). Method: Population-based multistage random sampling was used to recruit 1020 subjects who had no orbital or eye lid diseases and were free from systemic disease like thyroid eye disease that may affect orbital volume. These healthy adult subjects had their exophthalmometric values and palpebral fissure dimensions (horizontal and vertical palpebral fissure, lateral and medial canthal distances, inter-outer canthal distance, inter-inner canthal distance, margin reflex distance, and lid crease) measured with a Hertel's exophthalmometer and a plain non-stretchable plastic ruler, respectively. Results: A total of 1020 subjects (515 females and 505 males) of age range 16-85 years were studied. The mean ± SD exophthalmometric values were 15.27 ± 2.5 and 15.31 ± 2.4 mm for the right and left eyes, respectively. In the right eye, the mean palpebral fissure height was 8.3 mm, mean palpebral fissure width was 32.1 mm, mean upper eyelid crease was 7.1 mm, mean margin reflex height was 3.2 mm, mean lateral canthal distance was 12.9 mm, and the mean medial canthal distance was 10 mm at primary position of gaze. Conclusions: Exophthalmometric values and palpebral fissure dimensions were obtained among healthy adult Nigerians. Knowledge of these normal parameters is valuable in the management of eyelids and orbital diseases, as well as in manufacturing spectacles.