Presbyopia is an age-related condition of the eye in which the eye slowly loses the ability to focus quickly on objects that are close. It is a natural disorder that affects everyone, even those who have had no prior problems, typically occurring around the age of 40. Eye specialist believes that presbyopia is caused by changes to the lens inside the eyes.
condition-of-presbyopia
When young, the lens of the eyes is usually flexible, relatively elastic and the muscles surrounding it would easily reshape and adjust to accommodate both close and distant images. However, with age the lens and the muscles lose its flexibility and elasticity, becoming more stiff and rigid. Eye doctor believes that this would prevent the lens from changing its shape as quickly as it could, constricting the eye's ability to focus light directly onto your retina.
The first few signs of presbyopia are the gradual deterioration in the ability to read, having difficulty in reading small print or having eyestrain as well as headaches after reading or doing work up close. Patients would usually need to squint or adjust their reading materials to the 'appropriate' distance as well as require a brighter light to read or do work up close. Patients with presbyopia would also easily feel fatigue from doing all the tasks mentioned above and would have a problem seeing or focusing on objects that are up close. Today, there are many simple yet highly successful ways to correct refractive errors and conditions with little to no risk involved at all.
presbyopia-correction-implanting-a-multi-focal-lens
Before any presbyopia correction can be done, eye specialist would first assess patients to determine if they are suffering from cataracts. If they do, patients are presented with a choice between multi-focal lens technology or mono-focal lens technology for the lens implant surgery. These implants would be implanted during cataract surgery, removing all refractive errors including the likes of myopia, astigmatism and presbyopia to achieve spectacle-free vision. While it is implanted in the eye, multi-focal lens implants work similar to wearing 'progressive' spectacles which allow distance, intermediate and near focus. The brain will neuro-adapt to the multi-focal visual system postoperatively and will automatically select the eye to focus at whatever is the required distance.
On the other hand, mono-focal lens implant sets one eye for near vision, while the other mono focal lens implant sets the other eye to see the distance. The process of neuro-adaptation for mono-vision usually takes slightly longer, a week or two for the brain to adjust and begin to use the eyes naturally in a mono-vision manner. According to eye doctor, patients will never have to worry about spectacles and cataracts ever again as the power carried in the implanted lens are stable for the rest of the patient's life and cataracts can never return after it is removed. Both procedures take 15 minutes and is performed under local anaesthesia.
Younger patients with presbyopia but no cataract should be able to opt for LASIK as a presbyopia correction procedure. LASIK uses a laser to correct the shape of the lens, treating any refractive errors and restoring perfect vision. It corrects one eye's focus for far vision and correct the other eye's focus for near vision. The brain would merge these two images, enabling the patient to see relatively well at all distances. While it is a simple 10-minute pain-free procedure, LASIK mono-vision does not prevent cataract formation.
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