UNIQUE FEMTOSECOND TECHNOLOGY

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1 TECHNOLOGY BOOKLET

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3 UNIQUE FEMTOSECOND TECHNOLOGY The FEMTO LDV is a femtosecond laser which uses an oscillator as a laser source with high frequency output. As a consequence, it is not sensitive to environmental factors such as temperature and humidity, nor physical movement. The small size of the laser, equipped with wheels, makes it convenient to move between operating rooms and it fits with every excimer laser. Patients comfort is increased as they do not have to be moved. It is the only femtosecond laser which uses very low energy, working in the nanojoule and megahertz range. This results in extremely high precision and low side effects 1.

4 PULSE ENERGY I Conventional lasers with high pulse-energy High pulse energies create shock waves and large cavitation bubbles that induce stress in the surrounding tissue. The amount of disrupted tissue correlates with the strength of the pulse energy. 2 The volume of the disrupted tissue is larger than the focal volume of the laser and therefore less precise. 2 Spaces between the spots can result in tissue bridges. 3 pulse separation focus size

5 Ziemer's FEMTO LDV with low pulse-energy The cutting process is confined by the focal volume of the laser. Low pulse energies can only be achieved with a small focus. pulse separation focus size

6 PULSE ENERGY II The FEMTO LDV uses very low energy in nanojoules range. This is more gentle on the corneal tissue that surrounds the disrupted volume. 2 Cavitation bubbles in water Difference between nanojoules and microjoules (Courtesy of Prof. H. Lubatschowski) Pulse energy Gigajoule GJ Megajoule MJ Kilojoule kj Joule J Millijoule mj YAG-Laser, Excimer Microjoule µj other femtosecond lasers Nanojoule nj FEMTO LDV, Ziemer Ziemer FEMTO LDV nanojoules Other femtosecond laser microjoules

7 Pulse energy influence on corneal stromal cell death and inflammation The lower the pulse energy the less stromal cell death occurs. The lower the pulse energy the less inflammatory cell infiltration at the flap edge occurs. Stromal cell death after femtosecond laser treatment 4 TUNEL-positive cells (arrows) in the central cornea for the A) high energy 2,7 µj B) intermediate energy 1,6 µj, and C) low energy 0,5 µj groups, respectively. D) A cell undergoing apoptosis (arrow) in a control cornea, which is a rare event. Inflammatory cell infiltration at the flap edge after femtosecond laser treatment 4 CD11b-positive cells for A) high energy 2,7 µj. B) intermediate energy 1,6 µj, and C) low energy 0,5 µj groups. D) Unwounded control group.

8 SMALL FOCUS Numerical Aperture The larger sin α, the larger the numerical aperture is. The higher the numerical aperture, the smaller the focal volume. 5 NA = n sin α α n = refraction index α = half angle of aperture of the objective

9 A very small focused beam can be achieved with a very large lens diameter (1) or with a very short focal depth (2). 1 Increasing the lens diameter: leads to bulky systems 2 Decreasing the focal depth: needs a short working distance from the eye 2 which is only possible with the FEMTO LDV systems due to the unique designed handpiece which is applied directly to the eye. 1 2 Large focus (conventional femtosecond lasers) Small focus (FEMTO LDV)

10 REPETITION RATE Conventional laser systems The repetition rate of other femtosecond lasers is in the kilohertz range whereas Ziemer lasers work in the megahertz range. Megahertz MHz Kilohertz khz cycles per second cycles per second FEMTO LDV, Ziemer other femtosecond lasers Hertz Hz 1 cycle per second Distance between the center of 2 pulses is larger than the diameter of focus: no overlap

11 Ziemer FEMTO LDV With a smaller focus more pulses are needed to resect the same sized area. Therefore, the FEMTO LDV is working with a higher pulse repetition rate to keep the procedure time short. The FEMTO LDV produces a very small focus. With a high repetition rate, the spots are overlapping. This enables a smooth cut and a flap that is easy to lift without tissue bridges. 6 Dense spacing leads to overlap

12 CATARACT With the FEMTO LDV Z8* Ziemer is entering the cataract market using a fluid-filled patient interface. A fluid-filled interface causes a smaller increase in intraocular pressure (IOP) 7 which makes it safer to use for cataract patients. It also avoids corneal folds. 7 Only without corneal folds low pulse energies can be applied also to the lens. The capsulotomy is more predictable and stable with femtosecond laser than with manual capsulorhexis. A precise anterior capsulotomy is mandatory for intraocular lens implantation. Low pulse energy is also an important factor in femto-cataract surgeries: As shown in Table A, lower energy is favorable and results in a stronger capsule. A laser created capsulotomy may be more than twice as strong as a capsulorhexis created manually.

13 Capsule rupture force after manual capsulorhexis and laser capsulotomy with different pulse energies 8 Laser Parameter Manual 3 µj 6 µj 10 µj Mean capsule rupture force (mn) 65 ± ± ± ± 23 Number of samples Table A

14 THE ZIEMER FEMTO LDV AT A GLANCE On wheels, thus mobile Small Low energy High repetition rate Integrated lift Small focus overlapping Computer controlled vacuum system Small handpiece (handheld device) Robust system Swiss made technology equipped with wheels to move easily from one operating room to another or between clinics with its small proportions it fits in a van, with every excimer and in small operating rooms in nanojoules range in megahertz range the FEMTO LDV is adjustable for height due to small and overlapping cavitation bubbles it is very precise adjustable vacuum level is sensor controlled by computer high precision mechanics & optics are integrated in the handpiece which allows to work very close to the eye not sensitive to environmental factors such as temperature and humidity, nor physical movement

15 References 1 Lubatschowski, Applications of the femtosecond laser, Cataract & Refractive Surgery Today Europe, Lubatschowski H., State-of-the-Art Technology, Cataract & Refractive Surgery Today, 2008, Supplement «Z-LASIK in Practice» 3 Tomita et al, Evaluation of LASIK Treatment with the FEMTO LDV in Patients with corneal opacity, J Refract Surg ; 28(1) 4 de Medeiros et al, Effect of Femtosecond Laser Energy Level on Corneal Stromal Cell Death and Inflammation, J Refract Surg October ; 25(10) : Lubatschowski H., Overview of commercially available femtosecond lasers in refractive surgery, J Refract Surg ; 24(1) :S Vryghem et al, Efficacy, safety and flap dimensions of a new femtosecond laser for laser in situ keratomileusis. J Cataract Refract Surg ; 36 : Schultz et al, Intraocular pressure variation during femtosecond laser assisted cataract surgery using a fluid-filled interface, J Cataract Refract Surg 2013; 39: Friedman et al, Femtosecond laser capsulotomy, J Cataract Refract Surg, 2011; 37:

16 Ziemer Ophthalmic Systems AG a Ziemer Group Company Allmendstrasse Port, Switzerland Phone innovation@ziemergroup.com Ziemer Ophthalmology (Deutschland) GmbH a Ziemer Group Company Im Hausgrün Emmendingen, Germany Phone info-deutschland@ziemergroup.com Ziemer USA, Inc. a Ziemer Group Company 620 E. Third Street Alton, Illinois 62002, USA Phone usa@ziemergroup.com REF Doc. No.: FL * The Ziemer FEMTO LDV Z Models are FDA cleared and CE marked and available for immediate delivery. For some countries, availability may be restricted due to local regulatory requirements; please contact Ziemer for details. The FEMTO LDV Z8 is CE marked but not yet cleared by the FDA for the use in the United States. For other countries, availability may be restricted due to local regulatory requirements; please contact Ziemer for details.