Vitrectomy technology has changed little since Robert Machemer, MD, invented his 17-gauge single-port pneumatic cutter in 1972, Bausch + Lomb senior VP and chief medical officer Cal Roberts, MD, said at the “Retina Company Showcase” at OIS@ASRS 2016, but now B+L is working on a new approach to vitrectomy.
“Every vitrector works by pulling and then cutting, but suppose that we could cut the vitreous first and then just aspirate that which has been cut,” Dr. Roberts said. Plus add new technology that increases the vitrectomy cut rate from around 5,000 per minute with today’s machines to around 1.7 million cuts per minute.
A new attachment to B+L’s Stellaris PC platform, which is currently in development, uses hypersonic liquefaction in place of the conventional dual-needle guillotine cutter of conventional vitrectomy. The single-needle design works through a continuously open port. “The needle is mounted on a piezoelectric transducer element that vibrates harmonically to create a cutting rate of approximately 1.7 million cuts per minute,” Dr. Roberts explained.
Another innovation in vitrectomy development he shared is a new automated trocar inserter that will make an incision in the eye through which surgical ports are inserted. The new inserter will require “almost no pressure as we insert our cannula into the eye,” Dr. Roberts said.
Calvin Roberts, MD
Calvin W. Roberts, MD, is Executive Vice President and the Chief Medical Officer at Bausch + Lomb. A specialist in cataract and refractive surgery, Dr. Roberts is credited with developing surgical therapies, over-the-counter products for vision care, prescription ocular therapeutics, and innovative treatment regimens.
Calvin W. Roberts, MD: So the technology for performing vitrectomy has really changed very little since 1972, when Robert Machemer invented his 17 gauge, single port, multi-functional pneumatic cutter. So vitreous is aspirated into a needle, and then a guillotine blade cuts what has been aspirated. Now, over these 45 years, we’ve learned that the fast that you cut, the less is the amount of traction on the vitreous, and therefore the decreased risk there is to the retina. So today, modern vitrectomy technology operates at speeds of up to 5,000 cuts per minute. But suppose we could increase the rate of cutting, not from 5,000 to 10,000, but from 5,000 to 2 million cuts per minute? And every vitrector works by sucking and then cutting. But suppose that we could cut the vitreous first? And then just aspirate that which has been cut? So if you could increase the cutting rate to 2 million cuts per minute, cut first and then aspirate, wow, you could really decrease the amount of vitreous traction that occurs in vitrectomy. Introducing hypersonic liquefaction. If I could just back up one. So this is a new attachment to the Stellaris PC that in place of the conventional dual needle guillotine cutter, replaces it with a single needle designed with a small continuously open port. The needle is mounted on a pico electric transducer element that vibrates harmonically to create a cutting rate of approximately 1.7 million cuts per minute. So now the video on the left showed you a 5,000 cut pneumatic cutter, and you can clearly see how the vitreous is pulled in, and then cut. And you can see the traction that occurs on the vitreous continuously. While on the right, with hypersonic vitrectomy, the cutting is occurring so quickly that you are essentially having little if any vitreous traction at all. The photo on the left is an electron micrograph showing the vitrectomy specimen after pneumatic cutting, and you can see that the collagen matrix of the vitreous is intact, while on the right, after hypersonic liquefaction, most of the collage has already been fragmented. So again, comparing. Compared to the guillotine cutter, the port is open 100% of the time. The port size is about half the size, and speeds are occurring at approximately one and a half to 2 million cuts per minute. Like to also share with you a second innovation. And this is a different way in order to make this scleral incision that we need to do vitrectomy. So the graph below each video shows the amount of pressure that is required in order to puncture the globe. And you can see on the left, so this is manually, how it’s done manually. We mark, say 3, three and a half millimeters posterior to the limbus. And you see the pressure right there as we push in order to put the valve into the eye. Compared on the right with our auto inserter, notice here that there’s almost no pressure that goes as we insert our cannula into the eye. Suppose this was a soft eye. Just think what a difference it would make if we could insert our cannulas in a soft eye with so little pressure. So hypersonic vitrectomy and the auto inserter, two ways that Bausch and Lomb is improving vitreoretinal surgery for the benefit of doctors and patients. Thank you.