Eyeworld

53 EW FEATURE June 2016 • Controversies in ophthalmology AT A GLANCE • One benefit of using SMILE over LASIK is the lack of a flap, which can cause complications. SMILE is also thought to be a virtually painless procedure. • SMILE is currently only indicated for myopia. There may be other applications in the future. • SMILE may have slower visual recovery than LASIK, but some studies indicate that long-term results of SMILE are better. by Ellen Stodola EyeWorld Senior Staff Writer LASIK. At 3 months postop, qual- ity of vision and aberrations were better than wavefront LASIK. It was found that the optical zones were larger with SMILE, which translates to better night vision. There were not as many complaints of night vision problems as with LASIK. The accuracy of correction and safety were almost the same between the procedures, Dr. Ganesh added. The biggest advantage many see with SMILE compared to LASIK is the lack of a flap. "By decreasing the incision almost down to 2 mm, we eradicate several problems associat- ed with the flap," Dr. Sekundo said. SMILE has no pain, or only for a short period of time, and there are no problems with flap dislocation. On the other hand, SMILE is a much more demanding procedure, Dr. Sekundo said, and it is largely dependent on the laser and the surgical skill of the surgeon. The learning curve becomes evident in presentations at meetings, he added. In comparative studies, SMILE performs better in terms of stabil- ity, especially in high myopia, Dr. Sekundo said. Additionally, the regression rate with SMILE is smaller compared to excimer laser-based procedures. "The main advantages of SMILE are that the treatment is a flap-free procedure with minimal distortion of the corneal surface, and it does not induce spherical aberration possibly due to the physical removal of an intrastromal lenticule," Dr. Hjortdal said. However, SMILE does have a slightly slower recovery of visual Dr. Ganesh started doing SMILE about 3.5 years ago. Before that, he did a lot of femto wavefront LASIK. He thinks that SMILE is a better procedure, mentioning the risk of ectasia and the common problem of postop dryness with LASIK, as well as concerns with the LASIK flap. After first hearing about SMILE, Dr. Ganesh said he researched re- ports that indicated visual recovery was not as good as with LASIK. Now, he has performed close to 4,000 procedures and said that he rarely chooses LASIK anymore because he thinks SMILE is the better procedure. "As I refine my nomograms and techniques, I'm getting very good results," Dr. Ganesh said. "I person- ally think that this is the future of refractive surgery." Advantages and disadvantages There are a lot of benefits to SMILE for patients, Dr. Ganesh said. It's a virtually painless procedure and is quick. There is no long-term dry- ness, he said. After doing a comparative study between SMILE and femto LASIK several years ago, Dr. Ganesh said the refractive predictability of SMILE was found to be similar to femto Predictability and safety of SMILE and LASIK In both short-term and long-term results, Dr. Hjortdal said that pre- dictability and safety results seem similar between SMILE and LASIK. A recent meta-analysis 1 found SMILE and femtosecond LASIK were comparable in terms of safety and efficacy but that SMILE may cre- ate fewer dry eye symptoms than femtosecond LASIK, and corneal sensitivity was restored faster after SMILE compared with femtosecond LASIK, he said. Because LASIK has been in use for about 20 years, Dr. Sekundo doesn't see the introduc- tion of SMILE as controversial. LASIK is a well-proven and highly developed procedure, he said, but it's at the end of its development, and Dr. Sekundo doesn't think any- thing can be done to make LASIK better because "we've gotten to the stage where lasers and results are getting close to the variation in re- fraction." Refraction is dynamic, and from this point of view, LASIK/femto LASIK is a great procedure. SMILE is gaining popularity because patients desire this approach with a small incision and no flap, he said. The procedure is catching on in many countries around the world T he SMILE (small inci- sion lenticule extraction) procedure (Carl Zeiss Meditec, Jena, Germany) is increasing in popularity, with many studies on its results and how it compares to LASIK. Though it does not have as long of a track record as LASIK, which has been used for around 2 decades, SMILE is gaining ground, with particular ap- plication for patients with myopia. Jesper Hjortdal, MD, clinical professor, Department of Ophthal- mology, Aarhus University, Aarhus, Denmark; Walter Sekundo, MD, chairman, Department of Ophthal- mology, Philipps University of Marburg, Marburg, Germany; and Sri Ganesh, MD, chairman and managing director, Nethradhama Hospital, Bangalore, India, com- mented on their experience with SMILE, advantages and disadvantag- es compared to LASIK, and potential applications in the future. SMILE compared to LASIK and other procedures Slit lamp image taken 1 day after SMILE. It is hardly visible that the cornea underwent lenticule removal the day before. Source: Jesper Hjortdal, MD continued on page 54

• Cover