The age-related medical condition which results in the loss of a person’s ability to see objects clearly at a near distance is known as presbyopia. It is caused by a gradual and progressive hardening of the lens, which is accompanied by a decrease in the length of the ciliary muscle and a directly proportional decrease in its capacity to fully accommodate the eye for near distance objects. It most often manifests by the fifth decade of life and almost all older people, regardless of how perfect their vision was during earlier years, will experience it.
People may first notice that they have to hold their phones, books, newspapers and any other handheld object which requires close attention further away from their eyes than usual in order to see more clearly. This only partially remedies the problem, because the further away the object goes, the ‘smaller’ in size it becomes and accommodation further declines, thereby making ophthalmological intervention necessary. Other signs and symptoms of presbyopia include headaches due to eyestrain and eye fatigue as well as blurred vision. These symptoms are usually worse in dimly lit environments or after a long tiring day. This usually prompts those affected to pay their doctors a visit.
A basic and comprehensive examination of the eye with a series of different tests is necessary to diagnose presbyopia. The ophthalmologist will examine the retina and conduct muscle integrity, refraction, slit-lamp, visual field and visual acuity tests. These will help to ascertain the condition. Eye drops used during this process to dilate the pupils will cause patients to experience increased sensitivity to light in the few hours following the examinations.
Examination of the retina is called ophthalmoscopy or funduscopy. With the help of an ophthalmoscope the specialist can evaluate the retina, optic disk and choroid (i.e. layer of blood vessels responsible for providing nourishment to the retina). A muscle integrity test is done with a moving object and the ability to follow this object is evaluated. Refractive tests assess how well light waves are bent as they go through the cornea and the lens and the results of these tests help to determine which lens prescription will be needed.
The slit lamp is necessary for determining whether or not there are damaged cells at the front of the eye. It utilizes a microscope which allows for the magnification and illumination of this ocular area. The lashes, eyelids, iris, cornea, lens and the fluid chamber found between the iris and the cornea are examined. Testing the visual field is also called perimetry and it is done to determine if there are any deficits present in the field of the patient’s vision. Lastly, visual acuity tests, which most people are familiar with, are done with the help of a chart. Patients are asked to identify the characters that they see and this helps the doctor to determine how clearly the patient can see and at which distance.
Eye Examination Recommendations
Eye exams, according to the American Academy of Ophthalmology, are recommended every 5 – 10 years for adults under the age of 40 and every 2 – 4 years for those between the ages of 40 – 54. The interval decreases to every 1 – 3 years for those between the ages of 55 – 64 and persons 65 years and older should have their eyes examined every 1 – 2 years.
Reviewed by Liji Thomas, MD. References