 Hello, I'm Bob Sione from the Institute of Utah, Salt Lake City, and we're going to talk about vitrectomy for cataract surgeons. So why is it that we occasionally need to do a vitrectomy? Well, several things can happen either before, during, or after cataract surgery. The most common is intraoperative vitreous loss, due to an iatrogenic, iatrogenic pusher capsule tear, or zonular dialysis. However, sometimes we know there's going to be a problem even before surgery because the patient's had trauma to the zonules or caps or bag, and that invites vitreous to come forward, or they may have some disease or congenital conditions such as pseudoxfoliation or Marfan syndrome that allows vitreous to come forward through weakened zonules. So why do we need to do a vitrectomy in the first place? Well, vitreous in the anterior chamber is just not a good thing. It can cause an implant to be de-centered, it can cause an implant to tilt, and cause refractive error, it can misshapen the pupil and cause glare, it can cause chronic inflammation, cystoid macular edema, retinal tears, and retinal detachment. So in general, vitreous does not belong in the anterior chamber, and if during surgery you find it there, you should get it out of the anterior chamber. So what are some of the general principles for vitreous management during, in the face of cataract surgery? Number one, if you have nuclear pieces or an entire nucleus that falls down into the vitreous cavity, never chase it. Let it go. You can put an implant in, in front of it, you can suture to the iris, suture to the scleral wall, put an anterior chamber lens. Just make certain that the vitreous is not in the anterior chamber, close up, and you can refer that patient later to a vitreo-retinal specialist, or if it's the entire capsule or bag of nucleus in an elderly patient, that can probably even stay safely and not need to be removed. Second principle, never let the anterior chamber shallow. If you have vitreous that is starting to come forward, and you allow the anterior chamber to shallow through, let's say, a leaky incision, or an instrument that's going through an incision that's too large, you'll find vitreous come forward very easily, and then it's starting to come out of your incision, and that complicates the issue. Thirdly, never perform a wex cell sponge vitrectomy. If vitreous is coming out through an incision, you can carefully identify it and quickly lice it using a wex cell and a Van S. scissors, but you never want to wrap up vitreous around a wex cell sponge that tugs on the vitreous base and is very likely to cause a retinal tear and subsequent retinal detachment. You never perform your vitrectomy through a large incision. Doing so allows egressive fluid around your retrectomy cutter, and with a fluid will come vitreous, and it just promotes more and more vitreous prolapse. Triumph sinolone helps to identify vitreous in the anterior chamber. Vitreous can be invisible, and several years ago, a former partner of mine, Scott Burke, identified that putting triumph sinolone into the anterior chamber is almost like throwing a sheet over a ghost. It's suddenly identifiable and easy to manage, and we thank Scott for his contribution there. When you're doing vitrectomy, you want to pull the vitreous posteriorly, not anteriorly. If you pull it posteriorly, there's less stress on the vitreous base and less likely that you're going to have a retinal tear at it felt. So those are the general vitreous management principles. All in all, probably the preferred technique for vitrectomy is pars plana. Why is that? Because you are pulling that vitreous posteriorly. It's much more stable for the vitreous base. You want the vitreous to be in the vitreous space anyway, so pulling it back into that space instead of anteriorly where it doesn't belong is a safer procedure. It's definitely preferred. You don't want irrigation down in the vitreous space though. You want it in the anterior chamber. When performing a pars plana approach of vitrectomy, you still want your irrigation anterior to the iris. This is a slide that was given to me courtesy of Steve Charles. What are some key points from performing vitrectomy, either through two small incisions in the anterior chamber or through the pars plana? As you're making your sclerotomy, you clearly visualize your MVR blade in the pupil to make certain that you're through the uvial tissue in addition to the scleral wall before you place your vitrectomy cutter. You want to visualize your cutting port at all times and always move the cutter towards the vitreous. Don't pull away. Any pulling, any tugging on the vitreous can cause retinal tears. Never use aspiration without cutting if vitreous is present at the tip. There will be some times when you can use aspiration without cutting and we'll cover those times, but not when there's vitreous present at the aspiration port of your vitrectomy cutter. Always use the highest cutting rate available. You'll see in some of the video that the cut rates are as high as 4,000, which is now available on some of the machines such as Centurion and some of the cutting rates are lower, such as 800 from some of the older machines such as the Legacy, but whatever the highest cutting rate is available is preferred. Here's an example of things done wrong. The surgeon's name has been cropped out, so we can protect that identity, but we'll run through some things that could have been done better in this case. You see it's a very dense lens and tri-pan blue is being used, but it should have gone in before the viscoelastic was put in. It stains the capsule much more, much better than when you try to place it after viscoelastic is already in the eye. When making a groove in these dense lenses, you want to make a groove a couple widths wide. It allows better passage of the sleeve of that fecotip so you don't push the lens around too much and so you can get a deeper groove that is easier to crack. You can see the surgeon wasn't able to get a very deep groove and despite all attempts it's not able to crack this lens completely through the posterior plate and that's just going to make things more difficult. The surgeon is working more peripheral in this lens material and as you can see the fecotip is punching through the back portion of the lens not only engages iris but probably when it was back there it's very likely that it hit the posterior capsule too. So if there's a possibility that the capsule is open you do not want to pull suddenly out of the eye. What does that do? It allows the chamber to collapse and when the chamber collapse vitreous comes forward and as you can see we have a large opening in the posterior capsule vitreous forward and once again the surgeon comes out of the eye. Instead a better technique would have been staying the eye turn irrigation off and put viscoelastic in the eye to tamponade any further vitreous prolapse. And now the vitrectomy is being performed but it's being performed through a large incision so you can see vitreous material and fluid coming out through the large incision around the shaft of the vitrectomy cutter so no matter how much vitrectomy is being performed more vitreous is coming forward. Ideally you want to make a second side port incision and use the vitrectomy cutter through that side port incision and once again the surgeon is doing the same thing removing vitreous through that large incision when it really should be done through a side port incision. Now you will get away with it but it's going to require a lot more vitrectomy work and then it's necessary and it's much more likely that you're going to leave vitreous in the anterior chamber when it where it doesn't belong when it's done in this fashion. An anterior chamber vitrectomy is fine as long as you keep that vitrectomy port behind the iris plane most of the time. It might occasionally need to come anteriorly to remove some vitreous strands but in general you want it to be behind the iris plane. You can see that the attempt of placing this three-piece lens failed the first time partly the reason was that the surgeon was trying to get it into the ciliary sulcus right at the get-go while incision. It's easier to place it into the anterior chamber first and then manipulate it behind the iris. The surgeon is trying to manipulate the haptics behind the iris. It's a difficult maneuver to do so. Another way to do this is to grasp it with MST forceps while it's in the anterior chamber and manipulate the haptics behind the iris still holding on to the optic and then bringing everything forward. So this is actually a video of me doing this technique showing you a better way to place that three-piece lens preparing for iris fixation of those haptics to the posterior surface of the iris. And then each haptic can be sutured and we demonstrate this in another lecture but I just show it for completeness here. You can then place that needle around the haptic through the iris, externalize it and tie the suture with a seeps or not. The surgeon in this particular case is using a mechanical technique to fixate that haptic to the iris, not the best manner to fixate the haptic because the width of the cornea is interfering with getting that knot down tight on that haptic. And although the lens will center nicely at the time of the procedure, there's a higher likelihood that with it not being quite tight that implant may rotate and down the road and have some late dislocation. So here you see the surgeon back to the original case placing the haptic behind the iris and using the mechanical technique suturing the implant. Again, seeps or technique would be a better procedure for this, a better way to fixate the suture. Final detractomy is done here as well and you can see going through the large incision more vitreous comes forward and now there's iris prolapse that is encouraged by the vitreous prolapse. So once again I know I'm hitting it again and again and again, but please don't do your detractomy through a large incision. It's very easy to make a very small stab incision that's appropriately sized for the small diameter of the detractomy cutter. So this is a patient with a posterior polar cataract and they had an opening in the posterior capsule and I'm showing this video to demonstrate how you can prevent vitreous prolapse. So there's a large opening and notice that I'm using an appropriate sized INA tip and before I come out with the INA tip I'm going to fill the eye with viscoelastic while the irrigation is off that prevents vitreous from coming forward and then make a side port incision a small appropriately sized incision for the smaller bimanual INA tip and then we can very safely remove the remaining cortex without inviting vitreous prolapse. Once the chambers fill with viscoelastic we're going to then put in a three piece lens and capture the optic the haptics are in the sulcus the optics in the bag and that optic capture creates a seal so vitreous won't come forward. Now the second case is a patient that had late dislocation of a large single piece PMMA non-foldable lens and notice once again we made two small incisions so there would not be fluid egress along the shaft of the vitrectomy cutter. The vitrectomy cutter is initially brought into the anterior chamber where vitreous is forward and then it goes behind the optic to remove a layer of vitreous that is is resting just behind the optic. The optic is too large to create a capture so the vitrectomy cutter can be used to open the capsule or opening. Once the capsule or opening is more appropriately its size we there should then be able to keep the haptics in the sulcus prolapse the optic through that larger opening and that will create a seal between the anterior and the posterior segments and you can safely come out of the eye remove viscoelastic place myocall the myocall is there to not only reduce pressure postoperably but more importantly confirm that the pupil rounds uniformly meaning that there is no vitreous coming forward. Now this video shows that paris planavitrectomy approximately three millimeters posterior to the limbus or behind the implant and this is my preferred technique irrigation anteriorly vitrectomy posteriorly and that pulls vitreous back behind the eye along the vitreous base so you don't have that increased risk for retinal detachment. This last case is is demonstrating once again vitrectomy through a two anterior incisions notice that the vitrectomy port is posteriorly this is with an older machine but notice that now the cut rate is at zero so once vitreous is free you can turn the cut rate to zero and remove cortex if vitreous comes forward you immediately turn the vitrectomy cutter rate up again remove the vitreous and then when you go to remove further cortex you go back to a cut rate of zero and remove the cortex like it acts like a bimanual INA handpiece so you can go with the cutter on and off and that allows you to clean up that cortical debris in a safe manner without tugging on the vitreous. So in conclusion the trectomy can be performed safely by the anterior segment surgeon if anterior foetrectomy is performed do not use the main incision you should make two small incisions that are appropriate for the size of the instrument and that will prevent further vitreous prolapse. Parsplain of the trectomy is preferred because you're pulling that vitreous posteriorly that challenges the retina at the vitreous base less and when possible if you have it accessible try and sit alone injected into the anterior chamber will help stain and identify the vitreous so it's easier to see so you can be certain you remove it in its entirety. I'm Dr. Sione from the Institute of Utah in Salt Lake City, thank you.