Ziemer’s LDV Z8 is a portable, low-energy femtosecond laser system.

With its compact foot-print, low energy use and mobility, the FEMTO LDV Z8 (Ziemer Ophthalmic Systems AG, Switzerland) femtosecond laser is a unique, versatile system. The device is 3.3 x 2 feet, 4.6 feet tall and weighs less than 550 lbs,¹ which makes it easy to transfer between surgery suites or surgical centers.

With the FEMTO LDV Z8, neither the surgeon nor the patient are required to move to a separate operating suite, so a refractive procedure or femtosecond laser-assisted cataract surgery (FLACS) becomes a single uninterrupted process. Along with its handpiece attached to an articulating arm, this system results in a better patient experience and increased efficiency for the practice.

LESS ENERGY MEANS BETTER OUTCOMES

The FEMTO LDV Z8 uses low energy per pulse and a high frequency of pulses. The near-infrared, 1030-nm femtosecond laser is in the nanojoule (nJ) range rather than the microjoule (µJ) range, with a MHz repetition rate of up to a billion overlapping pulses per surgery to create a tight raster pattern.^2,3 The result is a smooth, complete cut without gaps between spots or tissue bridges.

Higher energy levels may result in transient light sensitivity syndrome (TLSS), according to Jeffery Machat, MD, a refractive surgeon based out of San Francisco, who has used the Ziemer family of lasers for more than five years. In his experience, TLSS does not occur with the FEMTO LDV lasers.

In a recent study by Riau et al comparing nJ energy to µJ energy, the authors found that nJ energy results in significantly less apoptotic cell death due to the absence of microcavitation bubbles, which other systems use to gently separate tissue.⁴ The result is less corneal damage, faster wound healing and better visual outcomes.²

FLACS with high-energy lasers can elevate prostaglandins and cytokines.^5,6 Lee McDaniel, MD, a cataract surgeon in Knoxville, Tenn., has experienced first-hand that reduced release of prostaglandins with the lower energy laser capsulotomy means less inflammation-induced miosis. Dr. McDaniel started using the FEMTO LDV Z8 in April and has used it for FLACS on more than 100 patients.

VERSATILITY

This technology offers an intuitive two-piece, perpendicular docking system that attaches to an articulating arm. It can be applied with an applanation interface in a variety of corneal procedures, including flap construction for LASIK, removing the risks of a microkeratome, or for creating tunnels for intracorneal ring segments.⁷

Dr. Machat has used the Ziemer series of lasers to implant upwards of 500 Kamra (CorneaGen) corneal inlays for the correction of presbyopia.

“The FEMTO LDV Z8 easily creates a smooth, large keyhole pattern, making it easy to place the inlay,” he says.

He finds the docking system offers a definite advantage: Thanks to the dock and articulating arm that allow the laser and patient to move together, the risk of breaking suction with patient movement is eliminated.

“Another advantage is the ability to change the procedure on the fly should special circumstances arise, such as corneal scars or pterygium,” Dr. Machat says. “The software is excellent, with lots of capabilities.”

FLACS WITHOUT GAS

The FEMTO LDV Z8 can be used for lens fragmentation, anterior capsulotomies and primary and secondary corneal arcuate incisions. The unique low energy of the device permits lens fragmentation prior to laser anterior capsulotomy, with minimal gas bubble production. This reduces the risk of intraoperative complications, such as a broken capsule.⁸

FLACS is achieved with a liquid-patient interface that decreases the incidence of posterior corneal Descemet folds, which can hinder laser beam transmission.² “The liquid-patient interface also reduces the risk of elevated IOP and results in fewer subconjunctival hemorrhages,” adds Dr. McDaniel.

The unit fits well under the microscope in the operating suite, where it easily integrates into the workflow for cataract surgery, say those interviewed. The mobile modular system offers image-guided surgery using spectral-domain OCT and a high-definition, integrated 24-bit color camera for clear visualization.⁷

INTUITIVE WITH A QUICK LEARNING CURVE

Dr. McDaniel felt comfortable performing FLACS with the FEMTO LDV Z8 after four or five procedures. A study of 14 eyes of cataract patients conducted by Pajic et al analyzed this learning curve. Time for the entire FLACS procedure with the FEMTO LDV Z8, including phacoemulsification, decreased from an average of 21.9 ± 1.8 minutes for the first three eyes to 12.5 ± 1.1 minutes for the last five eyes.⁹

Both Drs. Machat and McDaniel agree that the training offered by Ziemer to get the surgeon comfortable and efficient is invaluable. According to the company, that training typically consists of a didactic wet lab with physician and staff, support for two surgical days and postop review.

CONCLUSION

Dr. Machat offers this advice to his colleagues: “Everyone is focused on what they are used to doing, making it hard to contemplate change. But technology keeps moving forward, offering surprising new results. Think about the ‘wow’ factor of wavefront LASIK. The FEMTO LDV Z8 offers a low-energy, high-frequency laser with mobility, versatility and optimized outcomes.” OM

REFERENCES

1. FEMTO LDV/Ziemer Ophthalmic Systems. https://www.femtoldv.com/mobility.html . Accessed July 28, 2018.
2. Pajic B, Cvejic Z, Pajic-Eggspuehler B. Cataract surgery performed by high frequency LDV Z8 femtosecond laser: Safety, efficacy and its physical properties. Sensors (Basel). 2017;17:1429.
3. Jung SJ, Mehta JS. Effect of a low-energy femtosecond laser in cataract and corneal surgeries. CRST Europe. April 2017 suppl:4-5.
4. Riau AK, Liu YC, Lwin NC, et al. Comparative study of nJ- and μJ-energy level femtosecond lasers: Evaluation of flap adhesion strength, stromal bed quality, and tissue responses. Invest Ophthalmol Vis Sci. 2014;55:3186-194.
5. Schultz T, Joachim SC, Stellbogen M, Dick HB. Prostaglandin release during femtosecond laser-assisted cataract surgery: Main inducer. J Refract Surg. 2015;31:78-81.
6. Dick HB, Gerste RD, Schultz T. Laser cataract surgery: Curse of the small pupil. J Refract Surg. 2013;29:662.
7. FEMTO LDV Z8 Cornea Cataract: The mobile laser for corneal and cataract surgery. Available at https://www.femtoldv.com/brochures.html . Accessed July 28, 2018.
8. Lubatschowski H. Technology of the FEMTO LDV Z8: An overview. CRST Europe. October 2015 suppl:4-5.
9. Pajic B, Vastardis I, Gatzioufas Z, Pajic-Eggspuehler B. First experience with the new high-frequency femtosecond laser system (LDV Z8) for cataract surgery. Clinical Ophthalmology. 2014;8:2485-2489.