Clinical measurement on eyes and periocular areas: A Khon Kaen University study

Abstract

There is still no available dataset on the dimensions of prefabricated  ocular prostheses for the Northeastern Thai population. This pilot study aimed to report on pupil positioning, iris and scleral dimensions, and lateral eye curvatures among individuals at the Faculty of Dentistry, Khon Kaen University. It also explored the correlations between these measurements and key demographic variables, including age groups and gender. A total of 276 healthy participants were categorized by gender and further subdivided into three age groups: 20–30, 31–50, and >50 years. Standardized photography was conducted in a well-lit room. A Whibal card with a 10-mm scale was held perpendicularly to the subject. Its inner edge was positioned adjacent to the right nostril, and its top edge was placed 1 cm below the lower eyelid. Measurements included interpupillary distance (IPD), outer canthal distance (OCD), intercanthal distance (ICD), palpebral fissure width (PFW), palpebral fissure height (PFH), iris size, and the angles between the upper and lower eyelids. Group comparisons were conducted using t-tests and one-way ANOVA, with Tukey’s post hoc tests (p = 0.05). Gender significantly influenced IPD, OCD, PFW, and the upper-lower eyelid angle. Age significantly affected iris size, which was larger in the 20–30 group than in the >50 group. PFH was greater in the 20–30 group than in the >50 group and lower in the >50 group than in the 31–50 group. The upper-lower eyelid angle was more obtuse in the >50 group than in the 20–30 group. Males exhibited age-related differences in IPD, PFW, and eyelid angle, while females showed variations in iris size and PFH. These findings provide baseline periocular measurements which can be utilized to enhance the accuracy of stock ocular prostheses for the Northeastern Thai population.