Hypermetropia, sometimes called hyperopia or long sightedness often leads to problems with near vision, but it can also affect distance vision.
What is Hypermetropia?
Hypermetropia arises, when light is focused behind the retina because the eye is shorter than its focal length. To bring light into focus on the retina the lens in the eye is flexed by a process called accommodation.
Long-sighted people commonly become tired, from working hard to accommodate and focus on near objects. They may complain of headaches and eye strain or blurred vision, especially when doing prolonged close work or using a computer.
It is normal for infants and young children to have a small degree of hypermetropia that usually reduces as the eye grows longer with age. However, if severe hypermetropia is present from a very young age, and not diagnosed or corrected in time, a squint or permanently impaired lazy eye (amblyopia) can occur. In school children, moderate uncorrected hypermetropia can also result in learning difficulties, under achievement and even refusal to read.
Symptoms of mild hypermetropia often exhibit after childhood as accommodation (focusing) becomes progressively more difficult. Students may complain of symptoms of hypermetropia whilst studying for exams and require glasses which are only worn for close work. Hypermetropic adults over the age of 40 usually require corrective lenses for distance vision as well as a stronger prescription for close work, with the onset of presbyopia.
For children, regular eye examinations are recommended from birth to ensure normal visual development. Hypermetropia can be diagnosed by an optometrist during a routine eye examination, and is easily corrected with glasses or contact lenses. Positive lenses are prescribed to increase the overall power of the eye and reduce the effort on the visual system.