Time for a Phaco Upgrade?
Today's systems offer increased control and reduced energy in the eye.
BY LOU KOURY, CONTRIBUTING EDITOR

Currently available phacoemulsification systems offer an array of highly programmable features enabling surgeons to enhance their own specific techniques. They also deliver a reduced amount of energy into the eye and create less heat than their predecessors.

"When performing cataract surgery, today's ophthalmologist wants exquisite control and safety and the ability to minimize the total phaco energy placed into the eye, thereby increasing patient outcomes and satisfaction," said Uday Devgan, M.D., assistant clinical professor, Jules Stein Eye Institute, UCLA School of Medicine.

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According to I. Howard Fine, M.D., new refinements in power modulation allow surgeons to be highly specific when delivering energy appropriate for the density of a given nucleus. "Minimizing energy in the eye translates to better levels of visual acuity achieved more rapidly in the postoperative period," he said. Dr. Fine is in private practice at Drs. Fine, Hoffman and Packer in Eugene, Ore.

Such features are key to performing safe and effective bimanual microincision phaco, a technique that some surgeons believe will be standard someday. "Right now it is going to depend on the availability of lenses that go through the microincisions, but technology and instrumentation are being developed at a very rapid rate," Dr. Fine said.

Improvements in the delivery of infusion fluid to the eye are also on the horizon. "Improvements in fluidics will permit smaller phacoemulsification needles, with or without infusion sleeves, to accomplish the task of nucleus removal with excellent efficiency," said Richard J. Mackool, M.D., who is in private practice at the Mackool Eye Institute in Astoria, N.Y. "This will fit nicely with the anticipated arrival of IOLs that can be inserted through ever-smaller incisions."

Below is a review of the features of today's phaco machines, including recent upgrades.

Infiniti Vision System. The Alcon Infiniti Vision System, introduced in 2003, allows the surgeon to define his or her own surgical parameters. The surgeon can dictate the procedure by programming lens removal before the actual surgery takes place, according to Alcon. The system monitors each procedure, allowing adaptation to changing surgical conditions.

The Infiniti includes improved fluidics, a phaco mode that uses liquid pulses, and a redesigned physical system to enhance safety, control and efficiency.

Three different cataract removal modalities are possible with the system: ultrasound phaco with a light, titanium handpiece; advanced oscillation with the NeoSoniX handpiece; and liquefaction with AquaLase. The titanium handpiece is easy to hold and has an irrigation line that allows greater inside-the-eye control. The NeoSoniX handpiece makes surgery faster and safer, and combines sonic nonlinear oscillations with linear ultrasound. The AquaLase handpiece generates 4-microliter pulses of surgical solution that break up lens material and minimize thermal risk. No mechanical motion is involved, and the force of the pulse is dampened in the surrounding fluid so as not to disrupt nearby tissue.

The system's fluidics enable it to provide quick response while maintaining chamber stability. This makes the procedure predictable and protects against surge. Rise time is adjustable, so surgeons have more control.

"The most important function of a phacoemulsification instrument is its fluidics," said Dr. Mackool. "The Infiniti accomplishes this so exceedingly well that flow rates as great as 100 cc/min and vacuum levels of greater than 600 mmHg can be routinely used to remove the crystalline lens. When the fluidics excel, much less energy (be it in the form of ultrasound, NeoSonix oscillations or AquaLase water pulses) is required to accomplish removal of the cataract/crystalline lens," he said.

Other features offered by the Infiniti system are a redesigned user interface and a redesigned, ergonomic footswitch.

For more information, call (800) 862-5266.

Sovereign with WhiteStar 6.0. Advanced Medical Optics (AMO) recently introduced WhiteStar Version 6.0 for its Sovereign system, which offers Custom Cold Phaco. There are now up to four variable WhiteStar duty cycles in foot pedal position 3 for greater efficiency and control.

This upgrade to the Sovereign also includes V6 Fluidics, which enhance the fluidic capabilities of the Sovereign system to keep pace with the latest high-flow techniques. Both the Sovereign and Sovereign Compact feature digital fluidics and the programmable Occlusion Mode, which result in responsive vacuum and chamber stability.

According to AMO, using WhiteStar technology results in clearer corneas the first day after surgery because of reduced power and turbulence. The system holds and follows well and has more effective power for cutting while reducing cumulative energy by 30% to 40%.

Aron D. Rose, M.D., associate clinical professor, Yale University School of Medicine, said WhiteStar is a major benefit for surgeons. "In phacoemulsification today, all efforts appear to be directed toward applying more efficient ultrasound energy, which really means decreasing thermal energy," Dr. Rose said. "Further adoption of bimanual phaco will be the wave of the future, which is made possible by enhanced fluidics and reduced thermal energy."

According to Michael D. Colvard, M.D., Encino, Calif., the Sovereign system with WhiteStar is a perfect match for the ambulatory surgery center (ASC). "In addition to fostering safe and dependable phacoemulsification at reduced energy levels, it provides significant per-case cost savings because it does not require expensive wasteful single-use cassettes," he said. "This increases the profitability of an ASC, while providing the highest quality of care for the patients."

The Sovereign Compact system has an optional high-speed anterior vitrectomy module that is capable of 1,500 guillotine cuts per minute. Soon-to-be-launched software for the Compact will offer individually adjustable surgeon ramp speed for an even greater level of control and multilingual user interface options.

For more information, call (714) 247-8705.

Horizon Phacoemulsification System and SIStem. According to American Optisurgical Inc. (AOI), the Horizon unit is a complete anterior segment surgical system, providing functions including irrigation, multimodulation, phacoemulsification, I/A, anterior vitrectomy and bipolar coagulation. The unit is lightweight and portable, which is especially useful for surgeons who travel with their equipment. The company says the system is cost-effective, but also includes high-end features, such as a large LCD touch screen with user-friendly controls that can be preset with six different user programs.

The Horizon has a burst mode, infrared or wired remote control, programmable foot pedal and an easy-loading tubing cartridge. The ultra lightweight, all-titanium, 40 kHz, four-crystal, piezoelectric handpiece works with the multimodular phaco settings. Vitrectomy is performed with a pneumatic guillotine cutter that creates 50 to 700 cuts per minute.

AOI also markets the former Mentor SIStem. This unit with multimodular phaco settings offers up to 12 user programs, mini-peristaltic pump technology, a closed aspiration network called InstaLink, variable rise time and automated surge suppression. I/A is performed in a two-stage mode, the remote control is infrared and the ultrasound handpiece is small, lightweight, four-crystal piezoelectric. The aspiration flow rate is 0 to 40 cc/min, and vacuum range is 0 to 500 mmHg. The pneumatic guillotine cutter creates 100 to 600 cuts per minute. Surgeons can choose reusable or disposable noninvasive tubing.

For more information, call (949) 580-1266.

Millennium. Bausch and Lomb's Millennium Microsurgical System now uses the Advanced Flow System (AFS) high-performance positive displacement peristaltic pump. It has unique features that allow it to avoid the problems of post-occlusion surge and inefficiency that can be seen with other peristaltic pumps.

The AFS is a low-compliance fluidic system, which promotes a stable anterior chamber. It uses small inner diameter, thick wall pump head tubing which enable it to be responsive and efficient.

"This new peristaltic pump offers a full spectrum of customization so that it can emulate a slow peristaltic pump or a fast venturi pump, or any point in between," said Dr. Devgan. "The programmable level of vacuum responsiveness is coupled with a quick-venting, quick-to-react pump that provides a stable anterior chamber and virtually eliminates post-occlusion surge."

The Custom Control Software (CCS) for the Millennium combines a lower-frequency (28.5 kHz) phaco tip with hyperpulse power modulation. The company calls it "hyper-cool" phaco energy delivery. The hyper-pulse technology of 0 to 120 pps has an adjustable duty cycle, which delivers precision control and efficient cutting and reduces heat build-up.

The surgeon has expanded intraoperative control with custom power modulation. The ultrasound technique can be matched to the surgeon's preferences with a range of programmable phaco options.

"The other half of the equation is reducing the total phaco energy placed into the eye in order to cause less trauma to the corneal endothelial cells and to ensure a quick recovery, with clearer corneas on postoperative day one," Dr. Devgan said. "In addition, with the likely shift towards bimanual, sleeveless phaco surgery in the future, the CCS ensures that the phaco needle stays cool and does not burn the cornea. The level of programmability is extensive, with power modulations that not only decrease the energy placed in the eye, but increase the efficiency of the procedure as well, using parameters such as variable rise times, hyperpulse mode, hyperburst mode, and the ability to use the dual-linear foot pedal."

Dr. Devgan said that using the unit with these new features has been a benefit to his patients and his practice. It enhances safety and control and has decreased his total case times.

For more information, (909) 971-5294.

Sonic Wave Phacoemulsification System with Cruise Control. STAAR Surgical recently introduced the Cruise Control surge suppression device to enhance its Sonic Wave phacoemulsification system. The Cruise Control feature is a flow restrictor that uses a 15-mm cannula with a 0.3-mm lumen. Because it has increased length, it provides much greater resistance than an I/A tip. The device is located between the handpiece and the aspiration tubing. A mesh filter within the device traps debris from the lens and prevents it from clogging the lumen of the flow restrictor.

According to STAAR, phaco equipment has traditionally relied on the minimum inner diameter of the tip to provide a balance between holding power and chamber stability. As the minimum inner diameter is brought down, the vacuum level may be increased while maintaining chamber stability.

Cruise Control has the greatest fluidic resistance of any device and is the only one where the cataract material does not pass through the circuit's minimum diameter. With this device, the system fluidics are based on the device instead of the minimum tip inner diameter. Surgeons may use inexpensive 19-gauge standard tips with the vacuum level set at the machine's maximum potential. This enables the highest surgical efficiency possible within a solid chamber.

"STAAR has an excellent surge prevention device in the Cruise Control," said Dr. Fine. "The Sonic Wave is wonderful because it has capabilities for both sonic phaco and ultrasonic phaco. Sonic phaco is completely cool because the tip is vibrating at a frequency between 40 Hz and 400 Hz. When a surgeon uses the STAAR system, both sonic and ultrasonic can be used on the same eye, switching back and forth with a kick of the foot pedal. This allows very efficient removal of the lens material."

For more information, call (626) 303-7902.