Visumax, the only laser that can perform small incision lenticule extraction (SMILE), has won FDA approval.
SMILE is a minimally invasive, flapless procedure that some surgeons say may be superior to LASIK. The FDA approved Visumax to treat from -1.00 D to -8.00D of myopia, with ≤ -0.50D cylinder and MRSE-8.25D. SMILE is an established procedure in global markets such as Europe, China, Australia, Canada and India.
More than 800 surgeons have performed more than 500,000 procedures. One of them is Jesper Hjortdal, MD, PhD, Department of Ophthalmology Aarhus University Hospital, Denmark. At ESCRS 2016, Dr. Hjortdal told attendees he still performs LASIK, but SMILE has become his procedure of choice, adding that patients also find it appealing because it’s minimally invasive.
He describes the SMILE procedure as intrastromal refractive femtosecond surgery. Using a 500kHz laser, the surgeon cuts a lenticule within the cornea stroma, which is then removed through 1 or 2 small incisions. Bowman’s layer is preserved as a continuous layer and stromal fibrils at the anterior corneal surface remain intact.
Clinical studies have shown that SMILE can reduce corneal denervation and postop dry eye compared with flap-related refractive procedures such as LASIK, and may enhance biomechanical stability. Using Cochet-Bonnet esthesiometry, Dr. Hjortdal has shown that reduction in corneal sensitivity is significantly less with SMILE at 1 week, 1 month and 3 months after surgery. Confocal microscopy has also documented that corneal sub-basal nerve morphology is better preserved in eyes treated with SMILE compared with LASIK.
“We are thrilled that this exciting new technology is available for surgeons and patients in the US. I was very impressed with the excellent refractive outcomes in our clinical study, especially in those patients who were most dependent on their spectacles for daily life,” said Jon D. Dishler, MD, refractive surgery specialist of Dishler Laser Institute in Denver, Colorado, and US Medical Monitor for the VisuMax study.
The U.S. study treated 328 patients at five investigational sites, and showed good visual acuity and refractive stability: 88% of patients had uncorrected visual acuity of 20/20 or better, and all but one had uncorrected visual acuity of 20/40 or better.
Common complications noted in the U.S. study included difficulty removing the corneal tissue and suction loss. Postop complications included debris at the site of tissue removal, dry eye, moderate to severe glare and moderate to severe halos.
Dr. Hjortdal said that longer term follow-up of 1,800 eyes at his clinic in Denmark shows that although potential vision reducing complications can occur, no eye had lost more than 1 line of CDVA. One case of corneal ectasia has been reported, but it occurred in an eye with pre-existing abnormal topography.