Carl Zeiss Meditec
CZM has a million reasons to smile
Steven Schallhorn MD
Carl Zeiss Meditec celebrated one million reasons to smile at the XXXV Congress of the ESCRS in Lisbon recently. The company announced that more than one million small incision lenticule extraction (SMILE) procedures have been performed worldwide.
SMILE is a minimally invasive corneal refractive procedure performed using the ZEISS VisuMax femtosecond laser. It is a flap-free approach in which a corneal lenticule is removed through a small incision. Purported advantages include improved corneal biomechanics, no concern about traumatic flap displacement, lower incidence of long-term dry eye, and less damage to corneal nerves.
The SMILE procedure is now being performed in 65 countries by more than 1,300 surgeons in over 700 clinics around the world. The procedure received US FDA approval in 2016 for use in the reduction or elimination of up to -8.00 dioptres of myopia, with -0.50D or less cylinder and MRSE -8.25D in patients who are at least 22 years of age. The SMILE FDA approval and first commercial treatments in the US (March 2017) were important steps because SMILE is now available in every major LVC market around the world.
“SMILE has been out for over 10 years now and there have been close to 500 peer-reviewed publications about the procedure in the literature. We have many long-term outcome studies, some with over seven years, that suggest good visual outcomes and stability for the treatment of myopia,” said Steven Schallhorn MD, Chief Medical Officer for Global Ophthalmic Devices at ZEISS, in an interview with EuroTimes.
Dr Schallhorn noted those involved in the development of SMILE were able to take advantage of many lessons learned during the evolution of LASIK. SMILE was first performed in 2007 by Professor Walter Sekundo and represents the first major advancement in laser vision correction since the 1990s. The experience with LASIK taught the importance of understanding the reasonable capabilities of the procedure, and, equally important, careful patient selection, he emphasised.
Several recent clinical studies, including some that were reported at the ESCRS Congress in Lisbon, concluded that SMILE was as safe, and as effective, as LASIK for the correction of myopia.
Current research is looking at the role of SMILE for the treatment of astigmatism in the US, as well as hyperopia and presbyopia. Some unique applications were also presented. For example, Dr Soosan Jacob demonstrated a new technique to treat limbal dermoids using SMILE during the Lisbon meeting. (1)
After SMILE was introduced by early adopters, this unique procedure is now available for the broad community of ophthalmologists. Anyone interested in performing SMILE must complete appropriate training courses and are encouraged to attend peer-to-peer meetings. Moreover, ZEISS provides clinical application support, helping doctors get through the learning curve of SMILE, with the goal of delivering superior visual outcomes. The company also offers marketing and practice development support, in which consultants offer suggestions on such things as improving patient communications.
Dr Schallhorn was also enthusiastic about the AT LARA, ZEISS’ entry in the extended depth of focus (EDoF) intraocular lens field.
“The AT LARA EDoF is a good fit for the lifestyle of many patients that we treat today. It reflects the need that active patients have for spectacle-free intermediate near vision, such as using a smartphone, tablet or computer, which is a different visual task than reading small print in a book. It’s easy to appreciate that this lifestyle trend will continue,” said Dr Schallhorn.
LARA is an acronym that lists the features of the EDoF lens.
The initial ‘L’ refers to the light bridge optic design of the lens. “This refers to the unique optical design that provides an extended range of focus, a broad depth of focus. It is, of course, much different than a monofocal lens, and a significant improvement over the traditional bifocal lens,” said Dr Schallhorn.
The first ‘A’ in the acronym stands for ‘aspheric’, as the optic of the IOL is optimised for neutral asphericity to improve the quality of vision.
The ‘R’ refers to reduced visual side-effects provided by the design of the lens. He explained that ZEISS engineers applied a specific manufacturing process for the lens. The patented smooth micro-phase technology allows it to produce transitional phase zones, which minimises light scatter.
The final ‘A’ refers to the advanced chromatic optics of the IOL. “Chromatic aberration is an issue with all types of lenses, especially multifocal IOLs. The optical engineers at ZEISS designed the lens to minimise chromatic aberration for better contrast sensitivity,” he explained.
The AT LARA also has a 360-degree sharp posterior edge to minimise posterior capsule opacification. It comes preloaded to improve workflow, so that efficiency and productivity go hand and hand with this lens, he added.
“We have great confidence that this lens will deliver what the optical engineers have designed it to do; that is, provide a broad range of focus with few visual symptoms.”
In addition to his duties at ZEISS, Dr Schallhorn continues to practise surgery. He trained as an F-14 naval fighter pilot and was TOPGUN instructor in the US Navy before earning his medical degree. He retired from the Navy in 2007, where he served as the Refractive Surgery Program Manager. He founded the US Department of Defence refractive surgery programme, which now includes more than 20 centres offering refractive surgery to active duty personnel.
(1) Off-label use.