You Ask , They Answer
Q
: What are implantable collamer lenses ( ICLs ) and what types of conditions can they treat ?
A
: An ICL is a very soft special lens that is permanently implanted into the eyes of a patient to correct a refractive error without removing the eyes ’ natural lenses . For example , if patients are very short-sighted or have astigmatism , an imperfect curvature of the eye , we can use this lens to neutralise the refractive errors so they can see again without glasses .
Patients usually receive eye drops to numb the front part of the eyes where surgeons make a small incision of about 2.5 millimetres or less to place an ICL in front of the natural lens and behind the pupil . It takes about five to 10 minutes per eye and it ’ s painless , although patients are awake during the procedure . Although rare , an ICL can be removed or replaced .
Q
: How does it compare to laser refractive surgery ?
A
: Laser refractive surgery , usually referred to as Lasik , is still one of the most commonly performed surgeries to correct most refractive errors because it ’ s simple and effective , but it can ’ t treat patients who have very high myopia , like those who require a minus eight correction and above . ICLs play an important role in these patients who are not suitable for laser surgery because it can correct very high short-sightedness , allowing patients to get many years of meaningful vision without glasses .
Since the ICL procedure has been proven very safe , eye surgeons are now more willing to implant this lens even in patients who can undergo laser refractive surgery . But in my practice , we usually recommend laser surgery to patients who are suitable for it because ICL is more complex and expensive than laser , which has also been around longer than ICL and therefore is more predictable .
Q
: What are the risks associated with ICL ?
A
: Since you are introducing a foreign object into the eye , you could cause a serious eye infection , but this is very unlikely . The chances are similar to those associated with cataract surgery , so it ’ s a sort of theoretical downside .
The other disadvantage is that ICLs have to be removed when people develop cataracts , which is very common in those getting into their 60s or 70s . They can be removed safely in a couple of minutes , but that requires an additional step when surgeons also have to do an operation to treat cataracts .
In patients who don ’ t have enough space between the natural lens and the cornea , the procedure isn ’ t recommended as it could accelerate the formation of cataracts or lead to injury in the cornea .
Q
: How quickly do patients recover after ICL surgery and when can they see clearly ?
A
: During the first few hours after the procedure , vision will be blurry but usually becomes sufficiently clear after six hours . The next day most patients can see without glasses and will even be able to drive .
In terms of pain , they may have a mild discomfort when the anaesthesia wears off , but usually this can be relieved by pain killers , and in a few hours patients are comfortable again .
Q
: Is the procedure always successful ?
A
: About 95 percent of patients will be able to see well enough not to use glasses . In the remaining five percent , there may be some residual refractive error , but often it ’ s not too significant , and many patients can still see without glasses .
Dr Wong Jun Shyan
Dr Wong Jun Shyan is a consultant ophthalmologist and chief executive officer at the International Specialist Eye Centre in Kuala Lumpur .
12 MAY 2022 GlobalHealthAsiaPacific . com