A New Version of the Staar ICL (Implantable Collamer Lens) or “Implantable Contact Lens” Performs Well in New Study. For patients who are not good candidates for laser vision correction either in the form of LASIK or PRK — or for those who have extremely high degrees of myopia (nearsightedness) outside the range of laser vision correction, the phakic IOL can be a good option.
There are several brands and specific models of the phakic intracoluar lens or “phakic IOL”. These lenses are sometimes referred to as “implantable contact lenses” which actually is a bit of a misnomer. Unlike LASIK or PRK which correct vision at the outside surface of the eye, the phakic IOL involves inserting a lens into the inside of the eye. Because this is an intra-ocular (inside the eye) procedure, the risk of sight threatening complications traditionally is considered higher than an extra-ocular procedure like LASIK or PRK.
One of the most well known and, in the United States, widely used phakic intraocular lens is the Staar Implantable Collamer Lens (ICL). This lens is inserted behind the iris. One possible complication of insertion of this lens is the development of an acute attack of glaucoma caused by the lens pushing the iris outward from behind. This is called “pupillary block glaucoma.” In order to minimize the risk of this event, it is common practice for a surgeon to use a laser to punch a permanent hole in the iris (the colored part of the eye) to act as a sort of escape valve.
Staar has recently developed a new phakic intraocular lens which has a hole in the lens itself, which make it no longer necessary to place a hole in the iris (a laser “iridotomy”). This is, in theory, a big step forward and one that would improve the safety profile of the lens.
A recent study conducted in Spain looked at the performance of this new phakic intraocular lens. This study examined 138 eyes of 70 patients who had implantation of the new Staar ICL Implantable Collamer Lens for an average nearsightedness correction of -8.73 diopters, a fairly high degree of myopia. The new phakic intraocular lenses all had a hole in the lens and no laser holes were placed in the iris. In the study 92.1% of eyes achieved 20/20 or better vision. There were no episodes of glaucoma and the intraocular pressure remained normal in all patients at each exam.
This early study is very encouraging. Removing the need for a laser hole (peripheral laser iridotomy) make the procedure a more efficient and elegant procedure with a potentially better safety profile.
My preference stillis to perform either LASIK or PRK in patients who otherwise still are good candidates for these laser procedures, but for patients who are outside the range of correction for laser vision correction, implantable phakic intraocular lens technology continues to improve.
See Also
Clinical Outcomes After Implantation of a Posterior Chamber Collagen Intraocular Lens
A study confirms the excellent performance of a potentially safer new implantable collagen intraocular lens for correcting nearsightedness.
Phakic IOLs: A Progress Report
Despite much initial excitement among ophthalmologists, adoption of phakic IOLs in practice has not been that high.
Phakic IOLs (Implantable Lenses)
All About Vision review of phakic intraocular lenses, including the Visian ICL and the Verisyse.
Phakic Intraocular Lenses
FDA Website on phakic IOL technology.
Phakic Intraocular Lens Implantation for the Correction of Myopia: A Report by the American Academy of Ophthalmology
An American Academy of Ophthalmology Paper on the use of phakic intraocular lenses to correct myopia (nearsightedness).
Phakic IOL Implantation: Four Year United States Navy Experience
American Society of Cataract and Refractive Surgery paper on the U.S. Navy data for implantation of the phakic intraocular lens.