spotlight on technology & technique
Phaco for the 21st Century
A new instrument stretches the boundaries of what's possible in cataract removal.
By Christopher Kent, Senior Associate Editor

Sometimes progress is the result of a discovery or an ingenious new idea. Other times, progress comes from putting an enormous reserve of manpower and financial resources to work on a single project.

The new Infiniti Vision System for lens removal appears to be the product of both. Alcon -- a company with tremendous resources -- assembled a team of more than 40 scientists, engineers and additional support staff with the goal of creating a phaco system that was more advanced and ergonomic than any previous system. The team spent 4 years and $40 million researching and designing the Infiniti Vision System, with extensive input from surgeons. The result, according to surgeons who have used it, is impressive.

The Infiniti's features are noteworthy in several areas:

• It offers three different technologies for cataract removal in a single unit, including an entirely new phaco mode that uses pulses of surgical solution to break up lens material.
• It features improved fluidics, including dramatically reduced surge, rapid vacuum rise, and the industry's first irrigation line pressure monitor.
• The physical design includes a host of ergonomic changes intended to make the system easier -- and safer -- to use.

Three Options for Phaco

The Infiniti offers three different modalities for cataract removal:

Advanced ultrasound phacoemulsification. Improvements include:

• The ultrasound handpiece -- made of titanium -- is about half the weight of previous handpieces and has been redesigned to be easier to hold and manipulate.
• The irrigation line is now consistently oriented to the tip bevel, giving the surgeon better control inside the eye.
• The Infiniti has improved low-end ultrasound delivery, and it gives you linear ultrasound control across the entire power spectrum, from low-end to high.
• The system provides more accurate load sensing and response.

Advanced ultrasound with oscillation provided by the NeoSoniX handpiece. The NeoSoniX handpiece makes surgery faster and safer by allowing the tip to oscillate back and forth up to ±2°. It's the only handpiece that can combine sonic, nonlinear oscillations with linear ultrasound -- or use either alone.

When the tip is oscillating, ultrasonic energy is distributed, increasing the efficiency of delivery; it has the effect of moving the lens material on the tip, constantly repositioning the fragments. Some cataracts can even be removed using oscillation alone, reducing thermal energy as much as 99.7% compared to conventional ultrasound. You control both the amplitude of the oscillation and the threshold of ultrasound power at which it engages.

Studies have shown that phaco performed with NeoSoniX puts less energy into the eye than conventional ultrasound phaco.

Alcon's new AquaLase liquefaction device. The AquaLase handpiece generates 4-microliter pulses of surgical solution that can be used to break up lens material. Pulses are warmed and propelled by a smooth, rounded-bevel polymer reflective tip that disperses fluid for enhanced safety and "tissue specificity." No mechanical motion is involved.

The high-energy pulses cause gentle delamination and emulsification of selected tissue. According to Alcon, the force of the pulse is dampened in the surrounding fluid so nearby tissue isn't disrupted. This makes it possible to work deep in the capsule or in close proximity to other tissues with less risk of damage or complications.

AquaLase also:

• offers unique capsule cleaning capabilities
• minimizes thermal risk
• provides the familiar aspiration and irrigation functions
• gives the surgeon total control of all parameters.

Alcon also says that AquaLase is designed to be easy to learn and use.

New Fluid Management System

The Infiniti's fluidics include numerous new features and improvements over previous instruments, providing extremely quick response and maintaining a very high level of stability in the chamber. Improvements include:

Dramatically reduced surge. At 500 mm Hg, the Infiniti system has less than half the surge of the Legacy during an occlusion break. This is the result of a combination of hardware and software advances. For example, all fluid pathways in the instrument are composed of a rigid elastomeric membrane that improves fluid compliance.

Improved pump. The new pump gives you control over more parameters, including dynamic rise time (see next paragraph). It features a noninvasive pressure sensor that provides real-time vacuum information to the computer, making it possible to use higher vacuums.

Rapid vacuum rise. The Infiniti reaches almost twice the vacuum at 1 second that the Legacy reached. Also, the optional Dynamic Rise Time feature lets you precisely regulate the time to maximum holding force.

A real-time irrigation pressure sensor. According to Alcon, this is a first in the industry. The irrigation/infusion sensor automatically compensates for the slight compliance that remains in the system. (It also lets you know when the irrigation bottle is running dry.)

An entirely closed system. Because the fluid is contained within a closed system, you have total biomaterial containment in a consumable fluidic device that's discarded following the procedure. This results in a faster transition between patients and faster set-up, as well as faster tuning and priming.

	The Infiniti's AquaLase handpiece generates micropulses of surgical solution that break up lens material with minimal thermal risk or danger to surrounding tissue.

Smoothing the Road

In addition to multiple phaco technologies and enhanced fluidics, the design of the Infiniti offers numerous new ergonomic advantages:

Redesigned monitor and screen. The Infiniti lets you control all software and hardware capabilities via its touch screen. To enhance this:

• The monitor can tilt, swivel or rotate to accommodate any OR configuration. (It stores flat to protect the screen.)
• The screen is large, with highly visible and easy to understand displays and animated icons that focus on key settings and contexts.
• The system's graphic user interface has been designed to reflect clinical needs and concerns; instructions and prompts proceed in logical steps. (For example, during setup the screen shows diagrams of where to insert the cassette, what needs to be done next, and so forth.) It also clearly shows what type of procedure is being set up (or is active). Surgeons report that even when an experienced technician is absent, fill-in personal are guided so clearly that mistakes almost never happen.
• Memory settings are highly customizable.
• All critical parameters are actively monitored throughout the procedure.

Ergonomic footswitch. The footswitch has been redesigned for maximum ease of use:

• It's lightweight and can be moved with your foot, but locks down when your foot is on the pedal.
• It's totally mapable. You can assign up to six functions.
• It can be adjusted to fit the length and width of your foot.
• The front cord is placed so that it stays clear of instrument wheels.
• It stows inside the main unit, minimizing cord tangles.

Redesigned video-overlay system. This shows the live microscope view with current system parameters overlaid; the combined output can be recorded on a VCR.

New advantages include:

• The system displays more parameters, with greater accuracy.
• The system has a smaller and more compact design.
• It supports both PAL and NTSC formats.
• It's adaptable to almost every camera system in the world.

Other features. In addition:

• The compact wireless remote control is designed to mirror key screen controls and be easy to use.
• All panel connections are on the front of the instrument.
• The Infiniti tray arm is totally adjustable; it swings to either side and can be raised and lowered, to work for left- or right-handed surgeons. It includes a holding bay for the remote control.
• The tray also features a handpiece holder that keeps it in vertical orientation for priming, tuning and easy access.
• The body of the Infiniti features a tubing management system that keeps tubing organized and in place.

Comments From the Field

Robert J. Cionni, M.D., who practices at the Cincinnati Eye Institute, has used the Infiniti System for several weeks. He describes it as "phenomenal."

"It lets you work from a completely different and more logical mindset," he says. "You program everything ahead of time so that at the start of the procedure you only need to tell it which technique you'll be using (i.e., divide and conquer, phaco chop) and what grade of cataract you're dealing with. The sequence of steps then appears at the bottom of the screen.

"You can program the footpedal so it will progress through the prearranged steps and settings at your command. It can even be set to gently vibrate to alert you when you're about to enter phaco mode. All of this makes surgery simpler and safer," he adds.

"The low compliance gives the system much greater predictability and protection against surge. It also makes adjustable rise time possible, which allows you to be more aggressive or conservative during occlusions. It's built-in versatility."

Dr. Cionni is also impressed with the new AquaLase technology. "AquaLase has great potential," he says. "The polymer tip is much less likely to tear the posterior capsule. You can hold the tip against the posterior capsule and reach vacuums of 500 without breaking the capsule." So far, Dr. Cionni only uses AquaLase on grade 2.5 nuclei or less.

Asked to sum up, he says, "The Infiniti's three modalities, improved fluidics and versatility far surpass anything that's out there."

The Future is Now

It seems clear that this instrument has raised the bar for phaco technology once again. At a recent press conference, Richard Mackool, M.D., director of The Mackool Eye Institute and Laser Center and senior attending surgeon at the New York Eye and Ear Infirmary, called the Infiniti ". . . without question the most technologically advanced instrument ever created for removal of the human lens."

To find out more about the Infiniti, call (800) 862-5266 or contact your Alcon representative.