CAKE and PIE magazines’ Daily Congress News on the Anterior and Posterior Segments
The Many Roads to Refractive Surgery Success by Hazlin Hassan
I
n order for refractive surgery for myopia to be a success, it needs to safely achieve a patient’s desired refractive goal. But there are several ways of doing this, from laser refractive surgery to implantation of phakic intraocular lens (PIOL).
ICL, the winner
PIOLs beyond myopia
Phakic intraocular lens (PIOL) debates over the last two decades have pitted it against laser vision correction (LVC), with vigorous discussions over design, material, and patient selection.
PIOLs can not only correct myopia but it has a therapeutic role in anisometropic myopic amblyopia in children, said Prof. Ahmad El-Massry from the Faculty of Medicine at the Alexandria University in Egypt.
“PIOLs ICL is the way to go,” Dr. Alaa Eldanasoury of Magrab Hospital in the Kingdom of Saudi Arabia, told the session on Sunday at the still on-going 37th World Ophthlmology Congress (WOC 2020 Virtual®). What are the advantages of implantable collamer lens (ICL) over LVC? It preserves quality of vision for the rest of the patient’s life, retains the cornea biomechanics and there is no risk of ectasia. So why hasn’t ICL replaced LVC yet? Patients prefer LVC as the perception is that it is less invasive. LVC in low and moderate myopia is good enough to make them happy. But the cost of ICL is lower compared with laser. “They [patients] don’t know what they are missing. If they have an ICL, they will have better vision,” said Dr. Eldanasoury. An ideal PIOL needs to be biocompatible, stable, and predictable. It has to preserve quality of vision, allow fast recovery and be easy to remove or exchange. It must also possess a safe and long track record. “ICL’s superiority over LVC is documented. The safety of the collamer material has been proven over more than 25 years,” he concluded.
He shared a study on PIOLs to correct high myopia amblyopia in children which yielded the following results: More than 3 Snellen’s lines improvement of BCVA in all children, and no loss of BCVA in any patient. PIOLs were also very well tolerated in the pediatric eye. Results at 24 month showed a mean pre-operative BCVA of 0.2 (range 0.05-0.7), and mean postoperative BCVA of 0.8 (range 0.5 - 1.0). Anatomical outcomes included an excellent tolerance of ICLs, no inflammatory reaction, no elevation of intraocular pressure (IOP), good position of ICLs, and no cataract or secondary increase of IOP. “Collamer copolymer phakic ICL to correct high unilateral myopia is a good option in cases of moderate amblyopia with two years follow-up with good predictability, stability in refraction and IOP, no significant endothelial cell loss, better stereoscopic vision, and increasing in quality of life,” he said.
To SMILE or not to SMILE “Although SMILE is a promising technique for the correction of myopia and myopic astigmatism with
predictable, efficient, safe refractive and visual outcomes, complications can occur,” said Dr. Catherine Albou-Ganem of the Clinique de la Vision in Paris, France – the first French center entirely dedicated to refractive surgery, of which Dr. Albou-Ganem is a founding member. Most of these complications are related to inexperience, are included in the learning curve of the technique, and have a favorable resolution with no lasting effect on the patient’s final visual acuity, she noted. SMILE possesses several advantages. It is a less invasive corneal surgery, respects the biomechanical properties of the cornea and corneal nerves. There is also a lower risk of developing dry eye and recovery is simplified and shortened. SMILE is safe, predictable, stable, provides quality of vision, and at a high precision. Due to the absence of flap, the complications of SMILE are less numerous than in LASIK. Epithelial defects, according to published literature, are the most common complication at 41.9%. It is a mild problem solved in 1 to 2 days with the use of artificial tears, has no effect on visual acuity and presents only in the incision zone. Other complications include DLK, hazy interface, epithelial ingrowth, infection, interface fluid syndrome, dryness of the corneal surface, and ectasia. Overall frequency of postoperative complications was 8.6% which is comparable to what is expected after LASIK.
“Although SMILE is a promising technique for the correction of myopia and myopic astigmatism with predictable, efficient, safe refractive and visual outcomes, complications can occur.” Dr. Catherine Albou-Ganem Clinique de la Vision Paris, France
5
