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Upgrade may make traditional manual lens delivery a thing of the past
The addition of an automated IOL delivery system (Intrepid AutoSert IOL Injector, Alcon Laboratories) to a phacoemulsification platform (Infiniti Vision System, Alcon) provides superb control during IOL insertion.
By Lynda Charters; Reviewed by Robert H. Osher, MD
Cincinnati-Consistent IOL insertion through the smallest of incisions is reaching a new level of surgical control.
An automated IOL delivery system (Intrepid AutoSert IOL Injector, Alcon Laboratories), introduced in February 2013, is part of an upgrade to a proprietary phacoemulsification platform (Infiniti Vision System, Alcon).
In contrast to the variability associated with using a manual IOL injector, the automated IOL injector provides “superb control,” according to Robert H. Osher, MD, who performed the early laboratory investigations with the device and was the first surgeon in the United States to use it. He is professor of ophthalmology, College of Medicine, University of Cincinnati, and medical director emeritus, Cincinnati Eye Institute, Cincinnati.
“With the introduction of [this] injector, we finally have a superior, elegant delivery system,” he said, but achieving that end was not easy.
Every technologic innovation has pros and cons. The trend toward creating smaller and tighter incisions without compromising safety and quality began with phacoemulsification and ultimately resulted in the occasional IOL becoming oar-locked, or stuck, in the incisions.
As cataract incisions became smaller, the next step in this technologic evolution was the introduction of a series of injectors (Monarch, Alcon) to implant folded IOLs. A drawback was the requirement for the surgeon to use both hands to manipulate the device: one hand to stabilize the device, and the other to turn the screw injector. Because entering through the entire incision into the anterior chamber did not facilitate the smallest incision, the smallest incision was obtained by using the incision as an extension of the cartridge, meaning the IOL had to pass through a tight tunnel. This is when oar locking occurs, Dr. Osher explained.
He addressed this problem by changing the incisional construction through flaring the internal lips of the incision to 2.4 mm inside and 2.2 mm outside to facilitate IOL passage. European ophthalmologists then took another approach by changing the insertion technique to include a “patient assist” (i.e., patients were instructed to look toward the incision to provide countertraction of the extraocular muscles during manual IOL insertion to force the lens through the small incisions).
“This was akin to putting your foot on the patient’s shoulder and shoving the lens in,” Dr. Osher said.
Plung injectors were the next step.
“This allowed the surgeon’s free left hand to insert an instrument through the side port to stabilize the globe with the desired countertraction, and the right hand controlled the injector and the plunger,” he said. “This was a breakthrough.”
The subsequent introduction of a smaller D cartridge with 30% less room in the cartridge was a mixed blessing, Dr. Osher explained. With a plunger-type injector, the increased kinetic energy created as the lens passed through the cartridge occasionally could build up to a point at which the IOL exploded into the eye and control was lost.
“We now had a smaller incision, but a new element of danger that occurred rarely in the insertion process,” he said.
“The beauty of [the automated IOL delivery system] is that it allows use of the smaller D cartridge through a 2.2-mm incision with no explosion of the IOL into the eye,” Dr. Osher said. “Depressing the footswitch gently releases the IOL, and the surgeon’s left hand is free, allowing him or her to provide countertraction.
“We now have incredibly elegant, superbly controlled, consistent, and reproducible insertion,” he said. “The control is really unprecedented.”
Surgeons have options with this device in that they can choose the velocity of the insertion and the distance that the plunger extends.
“The incision quality is enhanced with the long-sought-after countertraction,” Dr. Osher said.
The automated IOL delivery system seems to address all the surgical issues.
“[The device] facilitates control of IOL insertion by use of a footswitch, selection of the desired speed of insertion, use of the smallest cartridge size, and use of the incision as an extension of the cartridge-all of which can only happen as a result of countertraction with the surgeon’s free left hand,” Dr. Osher said. “It’s all about control.
“This device allows control of IOL insertion through small incisions, making the process a safer and more predictable and controlled sequence,” he added. “After going from manual to automated IOL insertion, surgeons likely will never look back.”
Robert H. Osher, MD
Dr. Osher is a consultant for Alcon Laboratories. He has no commercial interest in this technology.