Double Chop fractures the lens in 2 hemipieces without the use of ultrasound or vacuum.

Those unfamilar with the technique are concerned about zonular stress because they think I'm pushing down on the lens. I am not pushing down on the lens. The chopper is supporting the lens from below and as I stab the lens with the phaco tip I bring the chopper upward. Both instruments meet in the middle and fracture the lens. To illustrate this point, I first place the chopper out to the equator, supinate my hand, and then tilt the handle vertically. You can visualize the chopper tip is actually more sideways which helps to support the lens from below. I hope this puts to rest the concern about zonular stress. This maneuver does not push down on the lens.

Some have struggled to achieve an effective chop. But first it is important to master horizontal chop. If you are not confortable with placing the chopper out to the equator, the you need to learn this before attempting double chop. Second, you have to know how to hold the chopper and the phaco tip. Normally, the phaco tip is held in a more horizontal or neutral position. Especially with sculpting, you want the phaco tip held so that it's acting like a shovel and scooping the surface lens material with U/S. In contrast, double chop is using the phaco tip as a mechanical chopper so the hand position is very different and held in a more vertical position. A more vertical position will allow the lens to be sandwiched by the chopper and phaco tip using diagonal vector forces to fracture the lens.

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