Using the "Quick Chop" Technique
How it works, and why it's still a good choice for many phaco cases.
BY ROBERT J. ARLEO, M.D.

Recent developments in the technology of phacoemulsification have enabled surgeons to safely use high flow and high vacuum levels during the phaco procedure. In turn, those high flow and high vacuum parameters have made it possible to develop new, more advantageous techniques for phacoemulsification. One of these is the "Quick Chop" technique, which I've used in the majority of my surgical procedures since the mid-1990s.

The Quick Chop technique uses high flow and vacuum to split a hard lens nucleus into multiple pieces for easy removal. Doing so has many advantages:

• Because it facilitates the creation of easily removable nucleus segments without sculpting, it's highly efficient. It takes less time than many other techniques and eliminates the phaco energy required to make grooves.
• It lets you stay away from the peripheral lens (which is helpful in small pupils).
• The technique is easy; it can be learned in a few weeks, with practice.
• If a problem occurs while you're learning the technique, you can easily revert to your "standby" method.

Here, I'd like to describe the Quick Chop technique in detail and offer advice to those trying it for the first time.

Setting Up

When you're first learning the technique, make sure to arrange the most favorable circumstances to help ensure
success. For example:

Choose ideal patients. This technique is easiest to perform with:

• a cooperative patient who will remain still and follow instructions
• adequate pupillary dilation
• a nuclear density of 2+ or 3+. This is dense enough for cracking, but easily emulsified.

Make sure you're comfortable using high flow settings. You should be comfortable using phaco settings on the order of 300+ vacuum, and 30+ aspiration flow rate. (The best time to become accustomed to working with these parameters is during the segment removal portion of the "divide and conquer" procedure.)

Use a first-rate phacoemulsification system. This means a system that can safely deliver high vacuum levels and flow. My preferred device for years has been the Alcon Legacy 20000 system; each upgrade to this system has improved the safety and efficiency of the surgery. I've recently converted to the Infiniti system, which does an even more extraordinary job of providing efficiency and safety.

In addition to using an excellent phaco system, I recommend using a Koch chopper (Storz E0713) to crack the lens. The Koch chopper is a straight wire with a 90° bend, rather short in length, with a dull tip.

Performing "Quick Chop"

To duplicate the method I use when performing Quick Chop, follow these steps:

Prepare the eye. After adequate pupillary dilation:

• Give the patient topical 2% lidocaine with epinephrine in the preoperative area. (Repeat after draping.) Then inject 1% MPF lidocaine.
• Fill the anterior chamber with Viscoat to stabilize the chamber and protect the endothelium.

Perform capsulorrhexis. Once the anterior chamber is stabilized:

• Make a paracentesis incision 45° away from the phaco incision. Don't make it too large or you may allow fluid egress during the surgery, destabilizing the anterior chamber. (I make mine just large enough for the cannula for the Viscoat to go through -- about 0.6 mm.)
• Make the temporal phaco incision. (I use a 3-mm dual bevel keratome.) Make sure the phaco incision is a good match for the phaco tip so it's fairly watertight during the procedure. I use a high infusion sleeve to increase fluid ingress and seal the incision.
• Next, make a 5.5-mm capsulorrhexis. Perform hydrodissection, not hydrodelineation.
• Confirm that the lens nucleus rotates freely.

Perform Quick Chop. Introduce the phaco tip and chopper into the main and paracentesis incisions, respectively. Then:

• Use a high level of vacuum at the phaco tip to get a firm hold on the lens nucleus. This is the single most important aspect of the chopping maneuver.
  To accomplish this, I prefer to use a 1.1-mm Kelman flared aspiration bypass system (ABS) tip. This tip holds the lens material firmly and also helps to maintain chamber stability when the occlusion breaks. In addition, the Kelman design has the right "angle of attack" for the Quick Chop technique.
• Next, drive the phaco needle deep into the central lens nucleus using one or two bursts of phaco energy.
• Once you've accomplished this, back off into foot position two and hold the lens with the vacuum. (Note: At this stage it's critical to avoid letting the vacuum drop, or going into foot position three. Doing so will cause a loss of occlusion and release the lens material.)
• While maintaining a hold on the nucleus with the phaco tip, introduce the chopper tip into the lens, just adjacent to the phaco tip. Now you're ready to begin cracking the lens.
• To create a crack, you need to make three simultaneous maneuvers: separate the nuclear material laterally and longitudinally, while raising the phaco needle and depressing the chopper.
  If done properly, these three simultaneous moves will crack the lens down to the posterior capsule, often bisecting it. The excursion of the movement is small, and the chopper merely serves as a point source of pressure to start the crack (much like using a spike to break auto glass rather than your fist).
• Once you've created a crack, rotate the lens 90 degrees, and repeat. (The phaco tip is still placed in the center of the lens in the space created by the first crack.)
• Continue rotating and cracking until you've created the desired number of segments. For most lenses, four segments are ideal, but a softer lens may only require three. A dense lens may require as many as six or eight cracks.
• Once you've created multiple fragments, emulsify them using the same vacuum and flow settings you used to crack the lens.
• Aspirate the lens cortex material and insert the IOL in the standard fashion.

When You're Just Starting Out

Needless to say, becoming proficient with this technique requires practice. Three of the most common problems are:

Letting the vacuum go. Once beginning surgeons have a good grip on the nucleus they tend to either let up on the vacuum or go into foot position three. Doing this during the chopping maneuver results in an ineffective chop, and also removes some nuclear material. If the surgeon persists, he'll be left with a bowl containing only nuclear rim, which can be difficult to remove.

If the first chop doesn't work for the above reasons, don't persist at that location. Rotate the nucleus 90° and try again. After three unsuccessful attempts, it's best to convert to a divide and conquer technique for the rest of the surgery and try again on another lens.

Using the technique on a soft lens. If the lens is too soft, the vacuum alone may continue to bring in nuclear material at the beginning, extending to the peripheral capsule. This type of lens is best handled using a different technique.

Problems with extremely dense lenses. These lenses may not fully crack down to the posterior capsule, or the fragments may lock together when you attempt to remove them. In this situation, it's best to begin by making a very small, deep central space using lower vacuum and flow. (Note: This space must preserve an adequate amount of dense nuclear material around the edges to allow grasping for the cracking maneuvers.)

A Great Alternative

Once mastered, this technique is a safe and efficient alternative to "deep dish" or "divide and conquer" surgery. The phaco energy and time savings are significant, and the technique is easy to use in a wide variety of situations, including dense cataracts, small pupils and surgeries involving visualization difficulties.

It's a valuable addition to any cataract surgeon's repertoire.

Dr. Arleo is medical director of the Arleo Eye Institute and a consultant for Alcon Surgical. He specializes in cataract and refractive surgery and lectures nationally on cataract surgical techniques and instrumentation.

Left to right: 1. Surgeon has impaled the nucleus and is holding it using vacuum (foot position two). 2. Cracking the lens with chopper (still in foot position two). 3. Rotating the lens for further cracking. 4 and 5. Removing segments.