Automated IOL insertion in routine and complex cataract surgery

Take-home

A one-handed IOL insertion device allows for smoother, less traumatic lens insertions even in difficult incisions and eyes.

Dr. MackoolBy Fred Gebhart; Reviewed by Richard Mackool, MD

Astoria, NY-Inserting an intraocular lens can be tricky.

Traditional technology, which was a practical technique in an era when incisions were large and there was room for error, requires two hands to position and control the injection device. If the eye depositioned slightly during insertion, there was room for recovery. However, as incisions shrink to 2.75 mm, 2.4 mm and 2.2 mm, the margin for error shrinks, too.

“If you are using two hands on the injector, you don’t have any extra hands to reposition the globe or the implant,” said Richard Mackool, MD, Mackool Eye Institute in Astoria, NY. “If the eye gets decentered, you can’t see quite as well and you can’t control where the implant is going quite as accurately. You can’t be as precise as you want.”

A new automated insertion device (AutoSert IOL Injector, Alcon Laboratories) restores that lost precision.

About the device

The one-handed device can be programmed for completely automated IOL insertion or controlled manually by a foot pedal.

“The capsulorhexis might be a little small, the incision might be a little tight, and you still want the lens to be inserted into the capsular sac as atraumatically as possible,” Dr. Mackool said. “The [device] makes those difficult insertions easier.”

Current trends in cataract surgery make an automated insertion device more attractive, Dr. Mackool said.

As surgical incisions continue to shrink, automated solutions will become more appealing. Though there is a certain degree of resistance to using ever-smaller incisions, biomechanical factors favor smaller, less invasive procedures.

A familiar 2.75-mm incision can produce half a diopter of flattening, Dr. Mackool said. But the degree of flattening varies from 0 to 0.5 D from eye to eye with little predictability.

“If your patient has 1 D of astigmatism and you are using an astigmatic IOL, you’ve got an unpredictable 0.5 D range of astigmatic effect from your incision alone” he said. “Half of your potential correction is lost before you even insert the IOL, nobody wants that kind of unpredictable outcome.

“Smaller and smaller incisions are a bigger and bigger part of accurate cataract refractive surgery and the [device] supports the kind of high precision surgery we all want to perform,” Dr. Mackool said. “It lets you work through a smaller incision and it helps you be more precise in every eye you work on.”

Importance of device

It is not clear if the new device makes a significant difference in long-term patient outcomes, he noted, but automated lens insertion does make a difference in perioperative complication rates and surgeon satisfaction.

“The real change in satisfaction is with surgeons,” he said. “Surgeons know when they are doing a quick and slick job and when they are struggling, and the reality, is that even when you are struggling to position a lens, things usually turn out okay. Maybe there is a little more postoperative iritis, but that generally goes away and it’s not a big deal.

“But every now and again it is a big deal because if you inject a ciliary focus lens behind the capsule, you’d better be a real expert. Repositioning that lens to the proper location is not an easy thing to do and it is those traumatic insertions that cause problems later.”

The cataract surgery ideal, Dr. Mackool said, is to complete the procedure without the eye noticing that it has been invaded. The incision and cataract removal should be:

·      Atraumatic.

·      Fluidics should not be altered.

·      Ultrasound should be minimized.

·      Nothing should touch the iris.

“If you have to struggle with the insertion and manipulate the lens into position, you are more likely to bump the iris and end up with iritis,” he said. “The more iritis you get, the greater the risk of macular edema you get. It’s a series of cascading events and the most effective way to stop the cascade is to prevent that initiating event.”

This is one more way to make cataract surgery and IOL implantation more precise, using a smaller incision so you get a better astigmatic result, Dr. Mackool said.

Because the surgery is more precise, less postoperative inflammation occurs, he said.

The eyes with postoperative inflammation do not see as well and as soon compared with eyes that endured less procedural trauma.

“[The device] helps you work quicker and slicker with less trauma,” Dr. Mackool said.

Richard Mackool, MD

Need author contact info and financial disclosure.

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