While laser vision correction procedures such as LASIK and
photorefractive keratectomy or PRK have been successful for many
patients, those who are extremely nearsighted or astigmatic often are
unsuitable for these procedures.
People who are unsuitable for LASIK may benefit from a surgical
procedure using intraocular lenses. The technique uses lens
replacements instead of lasers.
‘Phakic intraocular collamer lenses, also called Phakic IOLs or ICLs, have been found safe and effective for people with moderate to extreme nearsightedness or severe astigmatism, revealed a five year study.’
Phakic intraocular collamer lenses,
also called Phakic IOLs or ICLs, have been found safe and effective
after five years, revealed a research presented at AAO 2016, the
120th annual meeting of the American Academy of Ophthalmology.
To test the long-term safety and
efficacy of the procedure, researchers at Iran University of Medical
Sciences followed 31 people over five years to see how they fared
following the procedure. They found that the Phakic ICL procedure was
safe and effective for the majority of patients.
Researchers studied 60 eyes in 31 people who had Phakic ICLs to
correct moderate to extreme levels of myopia or severe astigmatism. They
chose people based on a number of factors, including those whose vision
was stable, who were not correctable with LASIK surgery and had no eye
disorders, such as glaucoma or macular degeneration.
Prior to the procedure, all of the people had 20/200 vision or worse
and only 60% could achieve 20/40 eyesight even with glasses or
contact lenses. Five years after having the procedure, the results were
- 57% of eyes (34 eyes) achieved 20/40 vision without the use of glasses or contact lenses.
- Another 23% of eyes (14 eyes) achieved it with the
addition of glasses or contacts. The researchers say that this is still a
positive outcome since none of the study participants could achieve
20/40 vision with glasses or contacts prior to having the procedure.
- Additionally, 20% (12 eyes) of recipients achieved
corrected visual acuity of 20/50 to 20/120 that related to underlying
retinal problems but had better vision than before surgery.
- 42 eyes were able to read at least one or more
additional lines on the chart than they could read before the procedure
when they were wearing their glasses or contact lenses.
- All of the lenses remained clear after five years, and none of the people who had the surgery lost visual acuity.
- In terms of side effects and complications, researchers found two
eyes needed realignment. Endothelial cell count decreased 11%.
Endothelial cells line the inside of the cornea and help keep it clear.
Over time, the loss of these cells can increase the chance of the cornea
clouding and is a potential risk of any intraocular lens surgery. The
11% decrease is within a range that the technique is considered
safe, researchers said. Further, the amount of endothelial cell lost
decreased in those who received a newer design of Phakic lenses
beginning in 2014, said researchers.
"The main concerns for this type of procedure are early and late
complications," said Seyed Javad Hashemian, ead author of the
study and director of the cataract and refractive unit at Rassoul Akram
Hospital and Iran University of Medical Sciences, Tehran. "This study
shows that if we have a complete pre-operative evaluation and choose
those who are most likely to be the best candidates for the procedure,
Phakic ICL implantation can improve quality of vision and function."
The researchers noted that larger studies should be done to verify their findings.