You Ask , They Answer
Q
: What are cataracts and can people detect them early ?
A
: This is a condition that reduces the transparency of the crystalline lens within the eye . People can only notice the disease when it becomes visually significant . For example , when people cannot improve their vision to at least 6 / 9 or 6 / 12 with glasses , we consider that visually significant . These numbers refer to the condition of people who can only see objects at six metres away while individuals with normal vision are able to see them clearly nine or 12 metres away . Very early cataracts that are not visually significant are very common , but we tend to manage those with glasses if necessary . Refractive errors such as astigmatism , myopia , and hyperopia may occur with cataracts and should always be excluded in people with suspected cataracts in order to make an accurate diagnosis .
Q
: Are there groups of people who are at a greater risk of cataracts , such as a patient ’ s family members ?
A
: Older people who have prolonged exposure to sunlight and perhaps dehydration are at risk . Other groups include those with diabetes mellitus or exposure to radiation and drugs like topical corticosteroids . Rare cases such as congenital or juvenile cataracts may be genetic or due to metabolic disorders , but these are rare compared to senile age-related cataracts .
Q
: Is surgery the only treatment option ? What does it involve and how effective and risky is it ?
A
: The only definitive treatment is cataract surgery . This involves extraction of the lens , usually by an ultrasonic
process called phacoemulsification and aspiration , and insertion of an intraocular lens . This is usually a day procedure and very effective . The main risk is endophthalmitis ( about 0.07 percent or one in a thousand ), an inflammation of the inner part of the eye which could be severe and blinding . There is a one in one hundred risk of other kinds of complications ( light sensitivity , swelling , inflammation , damage to surrounding eye structures ) which may require additional surgery or delayed recovery but usually have good outcomes .
Q
: Can people prevent cataracts ? How often should they see an eye specialist ?
A
: Pursuing good general health with a balanced diet and sufficient hydration while protecting the eyes from sunlight with sunglasses is the best prevention . People should see an eye specialist only if their vision cannot be corrected to be better than 6 / 12 with glasses prescribed by an optician or if their vision doesn ’ t permit making a living , e . g ., it ’ s too glaring or blurry to drive safely . Some people choose to see a community optometrist once a year or every two years to check for progression , if any . This would be a sensible approach since cataracts are so common and don ’ t change suddenly . Rarely , patients with medical conditions such as swollen or mature cataract , diabetic retinopathy which could not be managed properly , or dislocated cataracts also require cataract surgery but these cases would already be seen by eye specialists through other referral channels .
Professor Louis Tong
Professor Louis Tong is an eye specialist at the Singapore National Eye Centre .
10 ISSUE 2 | 2023 GlobalHealthAsiaPacific . com