THE VITRECTOMY LANDSCAPE

Brian Joondeph, MD, MPS

Vitrectomy system technology has been improving at a rapid rate in recent years, much like smartphones and smart watches. New features that were once the stuff of dreams are becoming the norm. Here, experienced surgeons share their impressions of the current vitrectomy platforms from Alcon, Bausch + Lomb, and DORC. While safety and efficiency are the primary goals, each system has a slightly different approach, yet all 3 systems share much in common. Just as in other areas of health care where the patient experience is paramount, in vitrectomy systems it is the user experience for both physician and surgical staff that is the gauge of success.

All 3 platforms use dual-cutter technology, first introduced by DORC, for improved efficiency and safety by removing vitreous faster while reducing vitreoretinal traction. Higher cut rates may augment the dual-cutter probes, although ever-increasing cut rates may hit a point of diminishing returns. The new frontier is fluidics, increasing flow through the cutter tip with infusion systems better able to keep pace with higher rates of aspiration.

Smaller is not always better, as we have learned over the years since the introduction of 27-gauge instruments. But hindrances, including reduced flow, diminished lighting and visualization, and overly flexible instruments, are all improved in the newest generation vitrectomy systems. Such upgrades may cause vitreoretinal surgeons to take a new look at 27-gauge surgery, because these enhancements are making this smaller gauge surgery comparable to the larger gauges to which surgeons are accustomed.

Surgeons and staff need an easy interface to perform surgery while minimizing distraction and delays. Fortunately, all 3 systems have easier-to-navigate control panels, foot pedals, and setup processes. For specifics of each system, see the below reviews by expert vitreoretinal surgeons.

ALCON HYPERVIT AND ULTRAVIT VITRECTOMY WITH THE CONSTELLATION PLATFORM

Martin Charles, MD, and Dina Abulon, MS

The aspiration of Alcon’s Hypervit dual-cutting vitrectomy probes is superb. During core and peripheral vitrectomy, there is a noticeable increase in probe aspiration compared to earlier generation cutters. In comparative bench studies, the 27+ gauge probes generated 63% greater balanced saline solution (BSS) flow and 26% greater vitreous flow than Advanced Ultravit single cutting probes when operating at maximum cut rate.^1,2 Similar to 27+ gauge performance, the 25+ Hypervit probes also generated increased aspiration flow (68% greater BSS flow and 44% greater vitreous flow) compared to Advanced Ultravit single cutting probes.^3,4 The probe design has evolved into a more effective cutter with optimized flow.⁵

The clinical benefits of small 25-gauge and 27-gauge vitrectomy with single cutting probes have been reported in several publications. Some benefits of minimally invasive, small gauge surgery included faster wound healing, reduced postoperative pain, and faster visual recovery.^6-11 Some disadvantages of small-gauge technology included reduced flow rates and increased vitrectomy duration, which required greater infusion pressure and vacuum to remove vitreous efficiently.^6-11 New dual-cutting Hypervit probes increase aspiration flow and counteract the restricted flow performance seen previously with single cutting, small gauge probes.

The improved fluid dynamics of Hypervit probes provide the surgeon with more control during vitrectomy, especially for dense membranes, hemorrhages, dropped lens fragments, and working near mobile tissue. The new probe design minimizes vitreoretinal traction and generates more stable flow. In laboratory studies, the 27+ gauge 20,000 cpm Hypervit probes generated 25% to 41% less peak traction forces than 10,000 cpm Advanced Ultravit probes.¹² The 25+ gauge 20,000 cpm probes generated 21% to 28% less peak traction forces than 10,000 cpm probes under similar flow conditions.¹³

Computer simulations of fluid dynamics near the probe port help explain why aspiration is more stable. With Hypervit, there is an 82% decrease in pulsatile motion compared to Advanced Ultravit probes (25+ gauge probes, 650 mmHg vacuum, 30 mmHg IOP setting).¹³ In other words, the reduced pulsatile motion at the port results in more stable aspiration flow and may allow for more control when working near mobile tissue. Another study further demonstrates the improved stability, control, and effectiveness of dual cutters during lensectomy. The 25+ gauge Hypervit probes provided more continuous engagement, more effective cutting, and less repulsion of soft and hard cataracts when compared to Ultravit 7,500 cpm lensectomy performance. In fact, the single cutting probes operating at maximum cut rate failed to aspirate lens material and required lower cut rates or switching to a different probe to complete the procedure. With the dual-cutting Hypervit probes, no failure was observed during the lensectomy study.¹⁴

The illumination that the Constellation Vision System provides is effective when working with the standard illumination probe and also when using the chandelier. I (Dr. Charles) use chandelier in every case except on macula surgery. The chandelier light helps me gain access to the periphery for autoscleral indentation and bimanual maneuvers. The 12 o’clock position is my preferred placement. There is also no compromise of visualization when choosing 27-gauge illumination.

The footswitch of the Constellation Vision System allows for easy access to all the functions from the pedal and programmability is convenient. My OR staff is comfortable using the machine with a user-friendly “plug and play” setup. Everything you connect to the Constellation comes with radiofrequency identification, so the system recognizes the disposables as you plug them in. All the functions we need are available in the same console: laser, gas mixing, vitrectomy and phaco capabilities for combined surgeries.

Fluid control is the most important features of the system. It gives the possibility of IOP control, proportional reflux, new probe designs with increased flow such as Hypervit, and facilitation of maneuvers such as scleral indentation (Figure 1).

The pneumatic hand piece is another helpful feature, which most surgeons around the globe do not know exists. You can plug any Grieshaber DSP tip into the handpiece and control the closure of the forceps or scissors with more precision.

The Constellation Vision System is fully integrated with the Ngenuity with Data Fusion technology. We can now start recording, invert the image, and visualize all the key parameters on the screen, such as irrigation flow, actual IOP, laser data, maximum vacuum setting, actual vacuum and vitrectomy cut rate. It has changed the way I work. I used the Constellation Vision System when it first launched in Argentina back in 2010. The various upgrades in both hardware and software have allowed for continuous improvement of the system.

BAUSCH + LOMB STELLARIS ELITE PC SYSTEM

Sunir J. Garg, MD, FACS

There are a number of exciting updates to the Bausch + Lomb Stellaris Elite PC System. It has provided me with improved functionality, efficiency, and instrumentation.

The upgrade that has made the biggest difference in my day-to-day life is the introduction of the Bi-Blade vitrectomy system (Figure 2). Available in 23, 25, and 27 gauge, it has dramatically increased the efficiency of my surgery. I’m able to perform a core vitrectomy much faster than I ever have before, which helps to shorten the overall case time. This has been an unintended benefit, which I greatly appreciate, particularly on a longer OR day. The Bi-Blade also gives me increased stability when I’m doing peripheral vitreous shave. This has been helpful in cases with mobile retina. About 7 years ago, I switched to doing all of my cases as 25 gauge. I thought this gave me a nice balance between small instrumentation and efficiency. However, after using the 23-gauge Bi-Blade, I’ve been impressed by how quickly I can remove the vitreous. I am now converting some of my traditional 25-gauge work over to 23 gauge to take advantage of this.

Another new offering is the FreeFlow vitrectomy system. With traditional infusion lines, when you put a small infusion line into a cannula, it is going to reduce flow. With FreeFlow, the infusion line fits over the sclerotomy cannula. This provides less resistance, which translates to better flow and results in greater intraoperative stability.

The Vitesse device is a hypersonic vitrectomy handpiece. Rather than cutting gel with a guillotine cutter, Vitesse liquefies the vitreous gel and removes it in microparticles. This has a number of potential advantages. First, there’s no concern about duty cycle because the port is always open. Also, because it doesn’t suck and cut, it may cause less traction on the peripheral gel, which increases stability when performing vitreous shave. The ultrasonic handpiece can also be helpful for removing small- to medium-sized pieces of retained lens material. This has not yet replaced my guillotine cutter, but as we continue to perfect the technique, and as we start transitioning to 25-gauge Vitesse, I anticipate using it more.

Finally, although less exciting than some of the bigger hardware and software changes, the new handheld instruments that are available have been really helpful. I’ve used the Reddy forceps on a number of occasions with excellent outcomes. This forceps has a somewhat abrasive distal tip that is helpful for peeling membranes. I generally use a pinch-and-grab technique, which has worked well for me; however, for some membranes, particularly glassy epiretinal membranes, scraping the membrane can be helpful. This forceps allows you to do that, and then, rather than having to switch instruments, you can use the forceps as you traditionally would to complete the peel.

The other instrument that has been helpful is the Pinnacle curved short-length forceps. Like many retina specialists, I’ve been doing a lot of intraocular lens work lately, including lens exchanges. For the Yamane technique, it is helpful to have perfectly designed curved forceps. We have a reusable forceps set, which has been designed for anterior segment work. One of the great things about disposable forceps is you never have to wonder if the instrument will be bent or has been properly cleaned. I also find it helpful to use the handle that I’ve become familiar with over time.

Bausch + Lomb continues to innovate and work with the retina community to enable us to take better care of our patients in the most efficient manner possible.

THE DORC EVA SYSTEM

Derek Kunimoto, MD

The DORC EVA System launched 2015 in the United States, and the EVA upgrade was launched in 2019. I have been a user of the system and its EVA upgrade since both were launched. The efficiency of the EVA TDC vitrectome is excellent. For core vitrectomy, EVA is superior and I typically do my core with “pedal to the metal,” running aspiration and cut rate at maximum. For peripheral vitrectomy, the highlight is precision with EVA. Precise control near the retina, both in the periphery and the macula, allow extremely close work to the retina without hesitation.

I see 2 benefits to the fluidics. Firstly, for mobile retina, the safety of EVA is remarkable. The flow mode, unique to EVA, provides exquisite control. Secondly, in core vitrectomy, it is important to have a good level of flow, and with EVA, the balance between flow rates and aspiration is ideal, in all gauges ranging from 23 to 27. This has not always been true with systems, especially historically.

I generally use 25-gauge illumination and am satisfied with the light output. With the EVA upgrade, the improvement in light output has been noticeable (Figure 3). Although I do not always need to use the maximum light output, it is great to know that it can be increased, and, importantly, the light output is also adequate for 27-gauge surgery. The upgrade removes one of the main limitations in moving to 27-gauge surgery.

I really like the redesigned footswitch available with the upgraded EVA. The biggest improvement in the upgrade is the integrated laser control. It is the first pedal to offer laser control without the need to break from the procedure to find the secondary pedal or lift a covering to use the laser pedal. For me as a surgeon, this is critical because it avoids the need to break concentration.

My scrub techs also find EVA easy to use. Priming the system is quick, even when requiring connection or repriming of a vitrectome during a procedure.

I would call attention to 2 features that set EVA apart. Firstly “flow mode,” because it provides a measurable and dramatic improvement to surgical management of a mobile retina. Secondly, the level of customization that is possible through the programming, the fact that settings can be fully customized to the preferences of any individual surgeon is a treasured feature of the system.

SELECTING A VITRECTOMY SYSTEM

Brian Joondeph, MD, MPS

These 3 systems are a quantum leap forward from past platforms, especially for “seasoned surgeons” who began their careers when 20-gauge surgery was the only option. Are the improvements enough to warrant the expense of a new machine replacing the most recent generation of vitrectomy systems? With declining reimbursements and hospitals and surgery centers still recovering from COVID shutdowns, upgrade decisions may be more circumspect than in past years.

My takeaway from these 3 reviews is that each of the machines is excellent, and there is no clear-cut winner. Test drive each of them, getting input from surgeons and surgical staff charged with setting up and running these systems during surgery. Also look beyond the technical capabilities to customer service. Complicated machines occasionally have glitches, in setup or during the case. Having a rep or technical advisor available when needed is the customer service piece that may be the deciding factor. Regardless, if you have the ability to upgrade your current system, it will be hard to go wrong with any of them. RP

REFERENCES

1. Abulon D, et al. Fluid flow performance 27 gauge dual cutters. Presented at: 19th Euretina Congress; Paris, France; September 5-8, 2019.
2. Zhu Y, Abulon D. Performance evaluation of 25 gauge 20,000 cpm vitrectomy probes: vitreous flow rates. Presented at: 22nd EVER Congress; Nice, France; October 17-19, 2019.
3. Abulon D. Fluid flow performance 27 gauge dual cutters (HV vs. AUV). Presented at: 19th Euretina Congress; Paris, France; September 5-8, 2019.
4. Abulon D. Vitreous flow rates of 27 gauge dual-cutting 20,000 cpm vitrectomy probes. Presented at: 22nd EVER Congress; Nice, France; October 17-19, 2019.
5. Abulon D. The impact of vitrectomy probe design on pulsatile motion during aspiration. Presented at: 19th Euretina Congress; Paris, France; September 5-8, 2019.
6. Kellner L, Wimpissinger B, Stolba U, Brannath W, Binder S. 25-Gauge vs 20-gauge system for pars plana vitrectomy: a prospective randomised clinical trial. Br J Ophthalmol. 2007;91(7):945-948.
7. Williams GA. 25-, 23-, or 20-gauge instrumentation for vitreous surgery? Eye (Lond). 2008;22(10):1263-1266.
8. Rizzo S, Genovesi-Ebert F, Belting C. Comparative study between a standard 25-gauge vitrectomy system and a new ultrahigh-speed 25-gauge system with duty cycle control in the treatment of various vitreoretinal diseases. Retina. 2011;31(10):2007-2013.
9. Kadonosono K, Yamakawa T, Uchio E, Yanagi Y, Tamaki Y, Araie M. Comparison of visual function after epiretinal membrane removal by 20-gauge and 25-gauge vitrectomy. Am J Ophthalmol. 2006;142(3):513-515.
10. Haas A, Seidel G, Steinbrugger I, Maier R, Gasser-Steiner V, Wedrich A, Weger M. Twenty-three-gauge and 20-gauge vitrectomy in epiretinal membrane surgery. Retina. 2010;30(1):112-116.
11. Goncu T, Gurelik G, Hasanreisoglu B. Comparison of efficacy and safety between transconjunctival 23-gauge and conventional 20-gauge vitrectomy systems in macular surgery. Korean J Ophthalmol. 2012;26(5):339-346.
12. Abulon D, Gariepy H. 27 gauge vitreous traction comparison: dual-cutting vs. single-cutting vitrectomy probes. Presented at: 34th Congress of Asia-Pacific Academy of Ophthalmology; Bangkok, Thailand; March 6-9, 2019.
13. Alcon data on file. Alcon Vision, LLC. June 2018.
14. Charles M, Abulon D. Dual cutting 20,000 cpm probe aspiration of retained lens fragment. Presented at: 2020 Virtual Annual ASRS Meeting; July 24-26, 2020.