Washington: Women`s eyes may actually be different from men`s as a new study has revealed that healthy emmetropic women have a bigger pupil diameter than men.
From an anatomical point of view, a normal, non-pathological eye is known as an emmetropic eye, and has been studied very little until now in comparison with myopic and hypermetropic eyes.
Normal, non-pathological emmetropic eyes are the most common type amongst the population (43.2 percent), with a percentage that swings between 60.6 percent in children from three to eight years and 29 percent in those older than 66.
Therefore, a study determines their anatomical pattern so that they serve as a model for comparison with eyes that have refractive defects (myopia, hypermetropia and stigmatism) pathological eyes (such as those that have cataracts).
“We know very little about emmetropic eyes even though they should be used for comparisons with myopic and hypermetropic eyes,” said Juan Alberto Sanchis-Gimeno, researcher at the University of Valencia and lead author of the study explains to SINC.
The project shows the values by gender for the central corneal thickness, minimum total corneal thickness, white to white distance and pupil diameter in a sample of 379 emmetropic subjects.
“It is the first study that analyses these anatomical indexes in a large sample of healthy emmetropic subjects,” Sanchis-Gimeno stated.
In recent years new technologies have been developed, such as corneal elevation topography, which allows us to increase our understanding of in vivo ocular anatomy.
Although the research states that there are no big differences between most of the parameters analysed, healthy emmetropic women have a wider pupil diameter than men.
“It will be necessary to investigate as to whether there are differences in the anatomical indexes studied between emmetropic, myopic and hypermetropic eyes, and between populations of different ethnic origin” the researcher concluded.
The pupil is a dilatable and contractile opening that regulates the amount of light that reaches the retina. Its diameter is between 3 and 4.5 millimetres in the human eye, although in the dark it could reach up to between 5 and 9 millimetres.
The study has been published in the journal Surgical and Radiologic Anatomy.