This video demonstrates the fundamentals of phacoemulsification surgery in detail and is recommended for residents and beginner cataract surgeons.
Surgeon: Dr. Wyche T. Coleman, III, Willis-Knighton Eye Institute, Shreveport, USA
[Wyche] This is Dr. Wyche Coleman. This video is intended to be a cataract fundamental video. There are many videos on the web that show advanced techniques but this one is directed specifically for residents and fellows who are perfecting their technique and need to get down the basics.
It’s unedited, we want to talk through every step if possible. We’ll make our paracentesis with a 15 degree knife. I look at the base of the blade where it connects to the plastic to make sure it’s not rotated. And I want to be about .5 to 1 millimeters anterior to the limbus in clear cornea. Try not to nick the conj, it’ll cause ballooning later in the case.
This is Shugarcaine. About 1cc is fine, you don’t have to overfill the anterior chamber to get adequate anesthesia and pupil dilation. We use Shugarcaine in all of our cases. When I started that I couldn’t come up with a reason not to. I do have one reason now and it’s that myostat doesn’t work quite as well if you need it. But I think you need it less often if you get adequate pupil dilation. We use Shugarcaine on every patient.
Here is Viscoat. We’ll come across the eye and then burp the lidocaine back out through the paracentesis. Try to get a complete fill but the eye doesn’t have to be too hard, just firm. Try not to cause too much discomfort to the patient. But get it firm enough, we can make a good main wound. The main wound starts .5 millimeters anterior to the limbus. We want to make sure that we don’t push it down when we’re making our main wound because that can track back into conjunctiva.
I like to puncture the anterior capsule with the keratome. I think this gives me a better starting point and more control at the beginning of my capsulorhexis. I’m going to go in with the Utrata forceps, tips closed, and lift up to get the rhexis going in the direction I want it, and then grasp.
We like to minimize the number of regrasps. In other words, get as many clock hours as possible per grasp because that improves your time and it eliminates the risk of having trouble regrasping midway through the rhexis.
In hydrodissection I use a Chang cannula, trait cannula is fine, Chang’s a little bit better at getting under the wound. We want to make sure that the tip is between the intracapsular leaflet and the cortex and not between nucleus and cortex. I don’t think hydrodelineation has much value. We want to make sure that it’s a real hydrodissection between the capsule and the lens.
Hydrodissection is about high pressure and low volume. We want pulses of high pressure. High volume is what burps the lens into the anterior chamber and prolapses the iris through the wound. High pressure and low volume is the key in small pulses.
I use a divide and conquer technique on probably 95% of my cases. It works on almost every density of lens. I’m going to use a groove and crack method. The lens is, on average, let’s say 3.5 to 5 millimeters thick, probably closer to five on most people who have a dense cataract. Tip is about 1.2 millimeters so we get three passes when we groove before we have to worry about the possibility of grooving through the posterior capsule. You don’t have to be timid on the first three passes, they can really be full thickness passes. And then we want to slow down and be careful on those last few.
The key to the crack is getting the Connor positioned deep down into the groove. The Connor should be slightly more posterior than the phaco tip. I’m going to lift the heavy nucleus up and I’m going to make sure that I crack off a complete quarter. We don’t want to take an eighth or a sixth because the other piece will be too big and it will be difficult to raise into the anterior chamber.
We’ll bring the other quarter up and we can remember now that the heminucleous that’s still present in the bag is holding the posterior capsule back, that’s really making our risk of touching the posterior capsule low at this point. That risk increases as we take more of the nucleus out.
We’re going to engage the nucleus, lift it up, sneak in behind with the Connor, and then we want to crack this as much as a perfect quarter as possible. Not a small piece, again, not a sixth or an eighth, we want a pure quarter if that’s possible. I think that’s the most efficient way to get the nucleus out. Now we’re being a little more careful protecting deep with our Connor. And on the last quarter we need to slow down, get the Connor deep in the center, and make sure that the posterior capsule does not come forward. The last quarter is when we need to slow down and be the most careful to prevent a posterior capsular rupture.
And now for cortical removal, it’s important to remember to move in an arc. We don’t want to just pull centrally because that puts more stress on individual zonules. If you move in an arc and you have someone with pseudoexfoliation or weak zonules for other reasons, it’s less likely to cause them to tear and vitreous to prolapse around the capsule. I also like to, once I’ve engaged to the cortex, it’s hard to see here, but I like to push down or posterior slightly, to create almost an U-shaped motion. We want to engage it by moving in an arc, then we want to add foot as we move down, and peel it away from the anterior capsule before we pull it centrally. I think that subtle little movement makes it a lot easier to get cortex efficiently and pull it in the direction to the most mechanical advantage.
We can polish a little if we need to. And polishing is really about contact and rubbing the surface of the posterior capsule more than it is about irrigation/aspiration. We want to be real gentle on the foot there.
When we’re injecting Provisc, or cohesive viscoelastic, we want to fill the bag first. Remember you can’t hit the posterior capsule with the cannula as long as there is viscoelastic actively being injected into the eye. It creates a fluid wave that protects the capsule. We fill the bag first and then the anterior chamber. We fill the anterior chamber first, we risk pushing the posterior capsule leaflet back and not getting a full capsular bag with space for the lens. I go in bevel up, I think that gives me a little more control of the eye without having to use a second instrument to stabilize.
Make sure that leading haptic is in the capsular bag. I want to push this lens straight down with the Connor. Get the haptic going out towards the equator, make sure it’s in the capsular bag. I usually remove the viscoelastic in the anterior chamber first then slide the lens over by pushing down on it as I gently touch. And then once I can get around the edge, lift up. And always when we’re using the I/A tip, if we’re looking down the bore of the port, it’s very unlikely to grab capsule. It’s when we have it tilted to the side where we can’t look directly into it that we’re at risk of grabbing posterior capsule or iris. Usually if we’re looking straight down the bore of it, it’s unlikely to be able to do much harm.
We’re hydrating our wounds. I always pick a point 50% between the inner and outer edge of the wound. I’m almost perpendicular with my cannula tip. Get in a good position and then get a hydration. A little reverse burp there to take the inner leaflet and make sure it’s laying flat on the cornea and it doesn’t allow fluid to continue leaking out. We can hydrate only half of our paracentesis in almost every case. Make sure that hydration comes all the way around to the other side and usually that saves us a step from hydrating both sides, as long as it’s well-sealed. Check it with a Weck-Cel, pressure looks good, lens looks well centered. This center cameral cefuroxime, thigomox is excellent also. I use it on every case.
Hope that helps you guys who are in the early stages of cataract surgery. Thanks.