Perfect Your Phaco Technique

Simplicity, along with a few new ideas, can produce excellent, reliable results.

BY PAUL S. KOCH M.D.

I will begin this narrative by sharing with the reader my preference that performing cataract surgery be as boring as possible. By this I mean having a surgical technique that is simple, reproducible, vanilla-flavored and neutral-colored. Surprises and adventures are to be discouraged, and observers in the OR should feel free to slip away after a few cases because there is nothing exciting to keep their attention. Complications should be compiled not by the percentage, but by the fraction thereof. Nothing recorded should qualify for a highlights reel.

For those readers who have thus far persisted and refrained from turning the page, I share here some rather firm opinions on how to perfect your phaco procedure by simplifying it to the extreme.

Incisions and Needles

I know some of my friends like small incisions and teeny needles, but I prefer to get out the nucleus chunks as easily as possible. I use a smooth, thin-walled, straight, untapered phaco needle because that’s the one with the widest bore I can find.

Don’t laugh at this next detail. My standard incision is 3.2 mm (I know, I know, you probably make one hundreds of microns smaller — big deal). The extra incision width lets me move my phaco tip left and right without being restricted. Tip restriction — oarlocking, as it was previously known — can limit your access to parts of the anterior chamber. It can also cause incision burns by forcing you to press your phaco tip against the internal edges of the incision.

The larger incision also makes it easier to inject the IOL afterward. I firmly believe that the increased rate of endophthalmitis seen after clear-corneal incisions is due to leaking, not location. Tearing the edges of the incision during lens insertion damages the seal, allowing leakage.

I also believe that the biggest surgical blunder I have made in the past decade was to accept stromal hydration as a reasonable technique for closing an incision. I now believe that stromal hydration is simply a way to mask a poor incision. If my incision leaks, even a little bit, I no longer reach for the syringe. I go right to the suture.

Infusion and Outflow

When you have a wide-bore needle, you must prevent surges, either by increasing inflow or limiting outflow. I increase inflow by making use of the air-infusion system on my phaco machine (Millennium, Bausch & Lomb, Rochester, N.Y.). I run an infusion line from the air pump into an infusion bottle. The pressurized irrigation from that bottle goes into another bottle and then through a 0.22-µm filter and then to the eye. The pressure in the bottles is regulated by a digital control on my machine, not by raising the bottle, so the bottles always remain at eye height.

I limit outflow by using the wonderfully inventive Cruise Control (Staar Surgical, Monrovia, Calif.) or the Flow Restricting Tubing (FRT, Hi-Vac, B&L). I’m sure there are others, but these are the ones I have used. Both have a phaco-tip–sized entry port to allow full aspiration of nucleus chunks, then a mesh screen to capture them. As the chunks are trapped in the mesh, the aspiration fluid passes around them through the mesh and thence to the cassette. Both have further flow restrictors, the Cruise Control in the diameter of its exit orifice and the FRT in its tubing diameter. These restrictors limit outflow so you can safely use vacuum levels far above those used for unrestricted phacoemulsification, theoretically as high as you might use for irrigation and aspiration. I routinely use vacuum levels during phacoemulsification up to 550 mm Hg.

Pulsing and Micropulsing

In my opinion, there is no question that pausing between pulses helps followability and reduces total phaco energy. Thanks to software built into just about every phaco machine we are able to adjust not only how long each pause is, but whether each ultrasound pulse is as long as the pause, shorter than the pause or longer than the pause.

My preference is to program three modes, and within each mode have the machine pulse as quickly as possible. They do not have to be especially precise or specific, just representative of a wide range of cataract densities. Every surgeon has his or her own comfortable pace so you should not take these settings as gospel, but I use about 30% on (70% off) for clear lenses and soft cataracts, 50% on (50% off) for normal cataracts and 70% on (30% off) for dense cataracts.

One Technique Fits All

I began this narrative with the admonition that my technique is a very simple and reproducible one. I shall now plead with the reader to refrain from yawning as I share the boring details.

My strategy is to have a procedure than can be used for just about every single cataract I might encounter. I do not wish one technique for a dense cataract and another for a soft; or one for a large pupil and one for a small. I want, as much as possible, to make the eye’s anatomy a non-factor in my surgical approach. What follows now is the latest iteration of years of simplification.

■ Sculpt the nucleus. Some readers might remember one of my slogans from phaco courses during the 1980s: “Sculpting is Good!” I felt then, and I continue to feel now, that we should remove most of the cataract during the most controlled part of the operation. During sculpting, nothing is moving, everything is held in place. What could be easier? It’s like you have a third hand in the eye holding the nucleus for you as you whittle away on it.

When I attend meetings, I do feel like sometimes I am the last sculpting surgeon in America, but I persist. I believe that sculpting is the easiest part of the operation, and so I routinely sculpt out a bowl about 6 mm in diameter, leaving behind a rim slightly wider than my capsulotomy.

Remember, I use a straight, thin-walled needle, so it is a very efficient way to remove nucleus. If the cataract is soft, I can do this in four or five passes of the phaco tip. If the nucleus is dense, I take smaller bites and constantly rotate the nucleus with the phaco tip until I chisel out my bowl.

My goal is to create a soft, easily sliceable nuclear bowl. Any part of the nucleus that’s going to be tough to remove is eliminated during sculpting. After that, all I have left is a soft rim that will be easy to remove.

Many people are astounded when they see me sculpt and quietly counsel that I can split the nucleus right away and get to segment removal earlier. “Bah!” I reply. This step is easy, safe and uneventful. That is why this operation is so simple. I eliminate any step that might make it difficult. I could split the nucleus earlier, but then I would have to deal with a large chunk of nucleus. Sometimes it would be a soft segment (Figures 1 and 2) and sometimes a rock (Figures 3 and 4). I would rather have everything the same, every time.

■ Chop, rotate and chop. Once I have my bowl, I gently place my phaco tip just inside the inner cut portion of the rim. It’s not necessary to bury the tip because it is only going to be used for resistance while chopping. My chopping instrument is a modification of the Minami M-Hook, the Koch-Minami Hook (ASICO, Chicago) designed to go around the entire outer equator of the lens and slice it right through its full thickness. It has a bulbous tip on its end so it can safely rub against the posterior capsule.

This hook is not absolutely critical to this technique and pretty much any standard chopping instrument can be used. I can slice through the nucleus rim with my hook; I can chop the rim with other hooks. As long as you have something that will break apart the rim you can continue from here.

Chopping is easy and quick if I don’t have to bury the phaco tip. When I pull on the nucleus during the chop it bumps up against the hovering phaco tip and stays there while the chop takes place. The phaco tip is the chopping block. After the first chop, I rotate the nucleus about 2 clock-hours and chop again. As I am doing this, the phaco tip stays in the same place — in the middle of the sculpted space, right next to the rim. This chop, rotate and chop is repeated until I have about six independent segments, each of them still completely covered by the anterior capsule.

Don’t forget that each segment is chopped from the peripheral, easily choppable nucleus. All of the hard nucleus was removed during sculpting. This makes chopping a breeze.

■ Remove the segments. Finally, I remove each segment. This goes quickly because each one is fairly soft. I do not search for any segment under the anterior capsule. I use the chopping instrument to pull it out to the tip. The phaco tip stays in the middle of the capsular bag, under the anterior capsule and away from the peripheral capsule. Removing each segment in the middle of the bag is both efficient and safe.

Now that you have read the steps in the operation, let’s review:

• Keep the nucleus in the capsular bag at all times — never let a segment escape into the anterior chamber
• Let the entire nucleus sit in one place while sculpting away most of its bulk
• Continue sculpting until left with a soft nuclear bowl
• Separate the rim into many small segments, then remove each segment using gentle emulsification.

It doesn’t get much easier than that.

I am sorry I did not have a fancy, thrilling phaco technique to share with you. All I can share is my simple, boring technique that is very safe and can be used with virtually every cataract.

I’ll make up for it now. Readers who stuck with me might like this next segment. It has some pretty cool stuff in it.

Pharmaceuticals

While my surgical technique has few surprises, I have adopted some novel approaches to the use of pharmaceuticals during the phaco procedure based on my own experience and the research and experience of others in the field.

■ Double up on anesthesia. I never scrimp on anesthesia. My operation cannot be boring unless the patient is completely comfortable; their groans and moans only cause me agita. I always double up on anesthesia by first using viscous tetracaine (TetraVisc, Cynacon/Ocusoft) prior to surgery. I have found it as effective as lidocaine jelly, but easier to use because it is an eyedrop. Once I am in the eye I add 0.25 cc of buffered 1% unpreserved lidocaine, prepared by mixing one part 4% lidocaine and three parts balanced salt solution (BSS, Alcon).

■ Add ascorbic acid to the infusion bottle. James Gills, M.D., introduced me to the research of Ehud Assia, M.D., who showed how antioxidants in the anterior chamber limit endothelial cell loss by restricting the collateral damage on neighboring cells that would be caused by the release of free radicals from the injured cells. Until studying his work, I did not know that our anterior chambers normally contain a little bit of ascorbic acid (Vitamin C). It is concerning, therefore, that just before we assault the eye during surgery we remove the ascorbic acid from the anterior chamber with viscoelastics and irrigations — just when the eye needs its protection most. To compensate, I now constantly replenish the ascorbic acid by adding it to our infusion bottle. We add 1.75 cc of 500 mg/cc ascorbic acid to a 500 cc bottle of BSS infusion, giving us a physiologic concentration of 10-3 M.

■ Irrigate with antibiotic and steroid. Dr. Gills also gets credit for introducing me to irrigating the anterior chamber with antibiotic and steroid at the conclusion of the operation.⁷ Let’s face it; the worst part about the cataract operation for most patients is using the eyedrops afterward. Many cannot follow our instructions because they forget, they cannot squeeze the bottles, they miss the eye, they depend on a friend and maybe they have no friends who can help. Despite the obvious limitations in compliance, we have blindly insisted that postoperative eyedrops be the sole method of avoiding infection and treating inflammation after surgery.

Think about it: we expend a lot of effort to prepare the patient, plan the procedure and perform a beautiful operation. Then, just as we finish our work, we give up control of the healing process. We abandon the patient to a regimen of eyedrops and a final result commensurate with their ability to use the drops. How much better would it be if the surgeon took control of the postop infection and inflammation management instead of sloughing off the responsibility on to an octogenarian?

I offer the option of intracameral antibiotic and steroids to all my patients and about four out of five select it. We irrigate a specially formulated suspension of unpreserved 1.5 mg of triamcinalone acetonide (not the Bristol-Myers Squibb Kenalog) and 100 mcg of gatifloxacin (Zymar, Allergan) into the capsular bag at the end of the case. Ninety-four percent of patients who receive this suspension do not need to use any eyedrops after cataract surgery. In the remaining 6%, the medication wears off before healing is complete and supplementary steroid eyedrops are needed.

Predictable Results

As I stated in the beginning of this article, when performing cataract surgery it is not my intention to bring any amount of excitement into the OR. My phaco technique incorporates a series of simple, streamlined techniques, along with some good ideas that I have picked up along the way from my colleagues. This approach has resulted in a surgical procedure that offers my patients solid, predictable results — which, I hope, is why they came to see me in the first place. Boring? Maybe, but it works for me. OM

Bibliography

Paul S. Koch, M.D., is the chief medical editor of Ophthalmology Management. Dr. Koch is the Medical Director of Koch Eye Associates in Warwick, R.I., and is a consultant for B&L and Cynacon/Ocusoft.