Microincisional Cataract Surgery: Harmony Ensures Success

Today’s phacoemulsification systems have made sub- 3.0mm incisions standard. Better fluidics control during smaller-incision surgery means we also have fewer collapsing chambers and fewer intraoperative problems. This is the main reason I use microincisional surgical techniques today. But it’s by far not the only one.

Another reason to consider microincisional surgery is because it helps minimise induced astigmatism, a critical factor in an age when patients are demanding true emmetropia, not just the spherical equivalent. Consider that a good majority of patients present with 0.5 D - 1.0 D of astigmatism. Cataract surgery, with some degree of induced cylinder, may result in a final astigmatism of 1.5 D or even 2.0 D. That’s not good enough.

Surgeons with a burgeoning presbyopia patient base must consistently achieve emmetropia. For our most demanding patients – those who want both their presbyopia and astigmatism corrected – we need to minimise the amount of induced astigmatism. With clear corneal incisions approaching 2.0mm or less, surgeons can reduce the amount of induced astigmatism to about 0.25 D. I believe patient demands will continue to drive our techniques to smaller and smaller incisions.

But none of that will matter unless there is complete harmony between the machine and the type of surgery one performs. For me, it is crucial that all the components of cataract surgery – the handpiece, phacoemulsification system, lens injector and IOL – work together, regardless of incision size.

For example, it makes little sense to perform surgery through a small incision only to enlarge the wound to insert a particular lens. Similarly, if surgeons try to squeeze a 2.2mm injector through a 2.0mm incision, they will either damage the wound construction or get a fishmouth configuration where the wound doesn’t close properly. This is problematic, because when the surgeon hydrates the paracentesis, the fluid just leaks out. This will result in a necessary suture and the astigmatic calculation will be off. In the end, I prefer enlarging the wound slightly over forcing an injector through.