Bausch + Lomb’s Vitesse vitrectomy system, approved by the FDA in April 2017, is the first and only hypersonic, 100% open-port vitrectomy system. The new technology marks the first major vitreous removal innovation in decades.
Vitreous removal has been traditionally performed with a guillotine-style vitrectomy cutter, a cutting mechanism introduced 40 years ago. “The guillotine technology has been effective for millions of vitrectomies, but the moving internal needle blocks the port when cutting and restricts the flow available through the larger outer needle,” says Brian McCary, director of innovation and design at Bausch + Lomb in St. Louis, Missouri. “It also pulls vitreous back and forth across the port, and interrupts the natural flow into the port on the needle tip. Surgeons continue to seek device evolution with the potential to improve surgical efficiency, fluidic stability, and diversity of application.” Vitesse features a novel, single-lumen design with a fixed open-port for a consistent flow that addresses these needs.
The device works by liquefying tissue immediately in front of the port, permitting it to be easily aspirated through the small port. The low velocity motion of the Vitesse needle creates high amplitude pressure/vacuum cycles inside the tip. These cycles cause fluid to flow at a high velocity through the port for very brief intervals, explains McCary. Given this, and the fact that the port is very small, high levels of shear flow occur in the port’s vicinity. This shearing action creates the liquefaction. The single-lumen design contrasts with pneumatically driven vitrectomy cutters, which employ a tube-within-a-tube design to perform a guillotine cut of the vitreous, which is then aspirated.
Carl Awh, MD, president of Tennessee Retina in Nashville, Tennessee, who was the first US surgeon to operate with Vitesse, says, “I’m impressed with my ability to use extremely low stroke (the distance of oscillation of the tip) and vacuum to work safely near mobile retina. I can remove large amounts of silicone oil from the eye with the Vitesse hand piece, something impossible with a guillotine-type pneumatic cutter. Although my experience is limited, it seems as though I can perform most of the techniques necessary to perform current vitreoretinal surgery.”
The Vitesse technology, featured exclusively on Bausch + Lomb’s Stellaris Elite Vision Enhancement System ophthalmic microsurgical system, includes a hand piece with a closed-end tip and a small port — between 175 µm and the equivalent of 255 µm in diameter — that vibrates with limited amplitude. The port is much smaller than ports on guillotine cutters of similar gauge, and there is no second inner needle. The small port limits the total traction force that can be exerted and is open 100% of the time because there is no inner needle that comes down to block it, McCary explains. Furthermore, flow up the inner lumen is not impeded by an inner needle. The hand piece liquefies the vitreous at approximately 1.7 million cycles each minute.
“The elimination of the inner element/tube of guillotine cutters substantially reduces resistance to flow and should enhance the device’s performance,” Dr. Awh says. “In the laboratory, we’ve found that by varying stroke, we have a much larger dynamic flow range than what is possible with traditional guillotine cutters. In other words, Vitesse is capable of reliable and predictable extremely low or high flow, with flow influenced by changes in stroke settings.”
EASE OF USE
The Vitesse system has been designed to minimize the learning curve and impact to clinical flow. The hand piece is single use, similar in size to a guillotine cutter, and is set up and primed in a similar manner, McCary says. Likewise, the needle length is similar to the needle length of guillotine cutters with equivalent gauge size, and the port is located on the side of the tip at the very end, in a similar location to that of guillotine cutters.
“Because the mechanism of action and the location of the active region are slightly different from that of guillotine cutters, Vitesse users will employ vacuum settings specific to the device and they select and control the tip stroke, rather than the cut rate,” McCary says. “There is a short adjustment period as they get acquainted with the new device’s performance.”
The trend toward smaller-gauge instrumentation, higher cutting rates, and high open-port duty-cycle cutters has been driven by the desire to make surgery easier for the surgeon and to minimize the impact of entering and exiting the eye, McCary says.
The handpiece is quiet because it is driven electrically; it does not have the sound or vibration associated with using guillotine cutters.
CLINICAL APPLICATIONS
Like guillotine cutters, the Vitesse system is currently indicated for use in removing vitreous and other tissue from the posterior segment. It has been used to perform posterior vitreous detachment and to remove vitreous, blood, and other substances from the back of the eye. Additional clinical applications are still under development.
“While we are excited about the potential for the Vitesse vitrectomy system technology, it is only one new aspect of the Stellaris Elite microsurgical system, which has additional advances in guillotine vitrectomy cut rates, anterior-segment infusion compensation, and a new BiBlade 27-gauge cutter,” McCary says.
Dr. Awh points out that, “Vitesse is a fundamentally different method of vitreous removal and tissue dissection that may provide greater surgical precision and efficiency than conventional pneumatic vitrectomy cutters.”
“This potentially revolutionary technology was compelling in the laboratory, promising in animal studies, and our initial experience in patients has been encouraging,” Dr. Awh concludes. RP