Phaco innovations

Figure 1 A new phacoemulsification system (WhiteStar Signature, Advanced Medical Optics [AMO]) features fusion fluidics designed to allow a surgeon to proactively adjust vacuum before an occlusion break and to switch back and forth between peristaltic and venturi pumps. (Photo courtesy of Advanced Medical Optics)

The year 2007 also was one in which two new phacoemulsification platforms (WhiteStar Signature, Advanced Medical Optics [AMO]; Stellaris Vision Enhancement System, Bausch & Lomb [B&L]) were showcased (Figures 1 and 2). Both platforms feature advanced fluidics systems designed to improve anterior chamber stability along with increases in power modulations and greater capability for microincisional cataract surgery (MICS). The former system features fusion fluidics that allow the surgeon to proactively adjust vacuum before an occlusion break and to switch back and forth between peristaltic and venturi pumps.

Figure 2 Built from the ground up, another phaco platform (Stellaris Vision Enhancement, Bausch & Lomb [B&L]) offers several novel design elements, including a wireless foot pedal. (Photo courtesy of B&L)

Dr. Olson noted he has just completed a laboratory study in which he used a very rigorous model to test post-occlusion surge and anterior chamber stability with the Signature, the Stellaris, and the Infiniti Vision Enhancement System (Alcon Laboratories). Based on his preliminary review of the raw data, he said, the Signature and Stellaris systems clearly represent a step forward compared with their respective previous platforms but also are several fold better than the Infiniti system.

"Preliminarily, the Signature came out slightly ahead of the Stellaris, but my study found that both offered incredibly stable performance under torture conditions," he said.

Dr. Olson noted both the Signature and Stellaris systems have very aggressive venturi modes. For Stellaris, that design is a carryover from its predecessor, the Millennium Microsurgical System. The new peristaltic mode on the Stellaris also performs very well, however, he said.

"Again, the final analysis is pending, and the Stellaris vacuum mode is not nearly as stable as the peristaltic system, but it is far more stable than what we had before. Further study is needed, but I can say the venturi modes of both the Signature and Stellaris will be stable enough so that surgeons can get very aggressive with their settings and still have very stable chambers," Dr. Olson said.

Built from the ground up, the Stellaris platform offers several novel design elements. Dr. Osher said that a wireless foot pedal is a particularly attractive feature.

Figure 3 Another phaco system (Infiniti Vision Enhancement, Alcon Laboratories) features new, stiffer aspiration tubing (Intrepid) to reduce compliance and surge. (Photo courtesy of Alcon Laboratories)

Dr. Fine characterized the new phaco systems as incremental improvements over the previous platforms. He noted that their design to enable MICS recognizes the future trend for that procedure to become increasingly mainstream over the next year or two. Alcon also continues to improve its phaco platform and introduced new, stiffer aspiration tubing (Intrepid) that reduces compliance and surge (Figure 3).

Torsional phaco

Figure 4 Interest in torsional phaco using a proprietary handpiece (OZil, Alcon) continued to build in 2007. (Photo courtesy of Alcon Laboratories)

Interest in torsional phaco using a proprietary handpiece (OZil, Alcon Laboratories) and the company's phaco system continued to build in 2007 (Figure 4).

"The jury is in. Torsional is fabulous technology, not just marketing hype. And a peer-reviewed study from Liu, et al., in the Journal of Cataract & Refractive Surgery confirms that it has benefits relative to longitudinal phaco," said Dr. Osher.

He added that video documentation from Teruyuki Miyoshi, MD, also supports torsional phaco. Dr. Miyoshi's entry claimed the grand prize in video competitions at the 2007 annual American Society of Cataract and Refractive Surgery (ASCRS) and European Society of Cataract and Refractive Surgeons (ESCRS) meetings and clearly showed that torsional ultrasound was associated with the less repulsion and chatter and better cutting efficiency compared with longitudinal ultrasound.

"There is no doubt that torsional ultrasound is a better way of lens removal, and it makes sense considering that, with longitudinal ultrasound, the nuclear material is being pushed away from the tip 50% of the time," Dr. Osher said.

Dr. Fine agreed that torsional ultrasound has an advantage over longitudinal ultrasound because it almost completely eliminates the repulsive forces at the tip. In contrast with many surgeons who have adopted torsional ultrasound for a coaxial MICS technique, Dr. Fine said he has been using it for bimanual MICS, but with a redesign of the tip. In addition to being sleeveless, this new tip features a 15 bevel down, with the position of the bend placed closer to the tip.

"This design contrasts with the bevel down tip developed by Takayuki Akahoshi, MD, and is the equivalent of a straight tip with a 30 bevel. Moving the site of the bend forward recognizes that a lot of cavitational energy is associated with the bend in the phaco needle and is intended to protect the incision," Dr. Fine explained.

In addition to having great success with this tip, Dr. Fine said that his experience has taught him the importance of avoiding occlusion with torsional phaco.

"This is something many surgeons don't appreciate yet. Over the past decade or so, we have gone from high-power phaco to a low-power technique using high vacuum as an extraction tool with power modulations for nudges of phaco energy," Dr. Fine explained. "Lens removal with torsional phaco is most efficient, however, if the material is sitting in front of the tip, where it can be sheared by the oscillating movement. When the tip is occluded, the fragment is being shaken, not shaved. For optimum efficiency, I have decreased my vacuum levels by 50 to 100 mm Hg to avoid occlusion and use 100% torsional with intermittent longitudinal bursts to kick the fragment off the tip if needed."

He added that this technique, which combines low energy with low vacuum, represents an additional step in the direction of minimally invasive cataract surgery.

Dr. Olson said that with his surgical technique, he has not found torsional to be a big advantage. He said that he still considers it an interesting and important feature, however, based on the favorable opinions of colleagues he respects and trusts.

Figure 5 As does torsional ultrasound, new ultrasound technology (Ellips Transversal, AMO) removes the lens with a shearing motion. (Photo courtesy of AMO)

Success breeds imitation, and surgeons can look forward to new ultrasound technology (Ellips Transversal, AMO) (Figure 5). Like torsional phaco, this new technology removes the lens with a shearing motion. Dr. Olson noted he has worked with this new technology in rabbit eyes and found its feel similar to that of torsional ultrasound. The movement is distinct, allows use of a straight needle, and can be combined simultaneously with longitudinal ultrasound at the same time, which is an interesting new twist, he said.

Bimanual MICS

Both Dr. Osher and Dr. Olson said they consider enthusiasm for bimanual MICS among cataract surgeons to be minimal.

"The results of every survey confirm what I have been saying for a number of years, which is that claims of interest in the bimanual technique have been blown out of proportion," said Dr. Osher. "I think that, with few exceptions, surgeons are convinced this approach is neither as safe nor as effective as coaxial surgery because of issues relating to fluidics, thermal injury, and incisional stress and competency. Furthermore, a requirement for new instrumentation, a significant learning curve, and the need to enlarge the incision or to create a separate incision to implant a full-sized, high-quality IOL provide additional obstacles."

He continued, "Perhaps when a microincision implant becomes available in the United States, interest in bimanual MICS will experience a resurgence. Even then, the procedure will need to be changed so that its many problems are addressed before it will be widely embraced."

Dr. Olson said he continues to believe that bimanual MICS has advantages, but he added that he recognizes he is among a minority of users in the cataract surgery community.

"When some diehards advocated this procedure for routine surgery, a lot of surgeons tried it, but they quickly backed off, and I don't see the market changing. Interest in bimanual MICS now is minimal and fixed," he said.

Nevertheless, Dr. Olson said he thinks that bimanual MICS is worth knowing about and using.

"There are times and difficult cases in which I wouldn't want to do anything else. Knowing it, having it, and using it on a regular basis helps me deal with those challenging situations better," he stated.

Dr. Fine said that he sees interest in bimanual MICS growing, at least in Europe.

"During the ESCRS congress in September, I gave a seminar on this topic at St. Erik's Eye Hospital, and I was surprised to see how many attendees were performing bimanual MICS—considering the low utilization in America," he said.

Dr. Fine suggested that the technique's greater popularity in Europe may relate to the availability of microincision lenses outside the United States.

"Perhaps once the implant technology is available in the United States, it will be the driving force for bimanual MICS in the same way that foldable lenses were the driving force behind the growth of phaco," Dr. Fine said. "Even in the absence of those lenses, however, I still believe that the bimanual procedure is a better operation because of the fluidics advantages of separating infusion from aspiration and phaco."

Microcoaxial phaco

Meanwhile, the performance of microcoaxial surgery is on the increase. It was first available using torsional ultrasound on the Infiniti platform, subsequently became an option using the Stellaris system, and is in development for use with the Signature platform. In the meantime, needles and sleeves available from MicroSurgical Technology allow microcoaxial surgery through a 2.0-to 2.2-mm incision using the Sovereign or the new Signature systems, said Dr. Olson.

Dr. Osher said that the microcoaxial technique overcomes many of the limitations of bimanual MICS, which would explain why it increasingly is being adopted. Microcoaxial surgery affords the thermoprotective advantages of a sleeved phaco tip, has been documented by various investigators to be associated with less incisional stress and better incisional integrity, allows delivery of a high-quality IOL with a full-sized optic, mandates minimal new instrumentation—just a 2.2-mm keratome and a one handed injector—and essentially has no learning curve, he said.

"In the interest of fair balance, there is a learning curve for lens delivery through a microcoaxial incision; it is a little difficult to perform in the first handful of cases," Dr. Osher said. "With a little practice, however, surgeons can quickly become proficient and achieve safe and reliable results."

His outcomes with microcoaxial surgery using torsional ultrasound speak to the advantages of the technique. Fabio Vaz, MD, a fellow working with Dr. Osher, conducted an independent review of 100 consecutive cases performed by Dr. Osher. The results showed that 98% of eyes had 20/40 uncorrected visual acuity (UCVA) on the first day after surgery, and 62% were 20/25 or better uncorrected.

"I can't begin to duplicate or even approach those results with bimanual MICS," Dr. Osher said.

Dr. Olson agreed that microcoaxial surgery is gaining popularity.

"There remains some question whether there is much gained by going from a 2.8-to a 2.2-or 2.4-mm incision, but Samuel Masket, MD, has good data to show that it is easier to create a square architecture with the smaller incision, and that results in a more stable wound," he said.

Although Dr. Fine said he favors a bimanual MICS technique, he added that he believes that microcoaxial surgery is a very important development because it improves chamber stability during phaco and reduces "trampolining" of the vitreous face. With the latter advantage, microcoaxial surgery may have a role in decreasing the incidence of retinal detachment in high myopes who undergo cataract surgery, he said.

IOL news

Figure 6 A microincision IOL (Akreos MI60, B&L), now available in Canada and Europe, features an aberration-free, aspheric optic, is constructed of a highly biocompatible hydrophilic acrylic material, has an innovative haptic design, and can be delivered through a 1.8-mm incision. (Photo courtesy of B&L)

A microincision IOL (Akreos MI60, B&L) may be on the horizon for U.S. surgeons. It is available in Canada and Europe and has been getting excellent reviews, said Dr. Osher. (Figure 6)

The lens features an aberration-free, aspheric optic, is constructed of a highly biocompatible hydrophilic acrylic material, has an innovative haptic design, and can be delivered through a 1.8-mm incision.

Dr. Fine said that he also considers the IOL very promising.

"It appears to have inordinate positional stability. That feature makes it look like it would be a great platform for a toric or multifocal IOL," he said.

Figure 7 A proprietary multifocal IOL (Tecnis ZM900, AMO) may become an important player for both bilateral implantation and for mixing and matching. (Photo courtesy of Daniel A. Black, MD)

Dr. Fine also said he is looking forward to the availability of a multifocal IOL (Tecnis ZM900, AMO) (Figure 7). Based on available data, he believes it will be an important player for both bilateral implantation and for mixing and matching.

Figure 8 An aspheric IOL (AcrySof ReSTOR aspheric, Alcon) introduced in 2007 is designed to improve resolution, contrast sensitivity, and depth of field, as well as give a more predictable A constant. It can be introduced through a 2.2-mm incision. (Photo courtesy of Alcon Laboratories)

Meanwhile, there were some important introductions in the U.S. IOL market in 2007, including an aspheric version of a lens (AcrySof ReSTOR aspheric, Alcon Laboratories) (Figure 8).

"Compared with the spherical version of [the lens], bench data clearly show the aspheric model improves resolution, contrast sensitivity, and depth of field, as well as gives a more predictable A constant. Most importantly, it can be introduced through a 2.2-mm incision, which is really astigmatically neutral. That is a critical benefit for a multifocal IOL where any surgically-induced astigmatism can interfere with the ability to achieve our goal of providing excellent UCVA," Dr. Osher said.

At the John Moran Eye Center, the aspheric lens is my premium lens of choice, Dr. Olson said.

"We could not see any reason not to use a multifocal implant that also offered asphericity," he said. "In choosing aspheric IOLs, I think cataract surgeons will be doing wavefront analysis more and more to select among the available choices, and we will see probably mixing and matching of these IOLs in the future."

Dr. Olson acknowledged, however, that controversy remains involving the appropriate target for postoperative spherical aberration. His own approach is to aim for neutral, he said, but others target some residual spherical aberration.

"There seem to be good studies supporting both approaches, but my own goal for now is full spherical aberration correction," he said.

Figure 9 A new accommodating lens (crystalens 5-0, eyeonics) introduced in 2007 has a larger optic than its predecessor and is expected to have improved refractive stability and to address the problem of capsular contraction syndrome. (Photo courtesy of eyeonics)

Also in 2007, a new accommodating lens (crystalens 5-0, eyeonics) was introduced. The lens has a larger optic than its predecessor and is expected to have improved refractive stability and to address the problem of capsular contraction syndrome (Figure 9).

Figure 10 The phase III FDA trial of a dual optic accommodating IOL (Synchrony, Visiogen) is close to completion, and the lens is being further evaluated in European clinical trials. The IOL can be implanted through a 3.6-to 3.8-mm incision. (Photo courtesy of Richard S. Hoffman, MD)

Still in development is a dual optic accommodating IOL (Synchrony, Visiogen) (Figure 10). The phase III FDA trial is close to completion, however, and the IOL is being further evaluated in European clinical trials.

"A major development with this IOL is that it can be implanted through a 3.6-to 3.8-mm incision," said Dr. Osher. "So far, the company has reported terrific results. However, more data are needed to answer important questions, such as how easy is it to achieve refractive accuracy with its implantation and whether the outcomes are durable over the longer term."

Based on favorable results with the dual optic accommodating lens, Dr. Olson said he would not be surprised to see it receive FDA approval in the coming year. Ongoing studies to gain a better understanding of how the lens works indicate that it provides a true accommodative change.

"My biggest concern about this lens was that the two optics would be pinned together once the capsule contracts. However, based on the work we have done in rabbits and in clinical trials so far, that does not appear to be a problem," Dr. Olson said.

He said that it does appear to be a little bit more difficult to achieve perfect distance correction with this technology because the two optics may separate in the resting state to result in myopia. In terms of presbyopia correction, however, the lens does seem to be performing as a true accommodating IOL. In that respect, it will offer advantages compared with a multifocal implant that can result in problems with glare, halos, and loss of contrast sensitivity, Dr. Olson said.

Dr. Fine echoed his colleagues' comments in describing the results being reported for the dual optic accommodating lens as "spectacular," and added that it is providing unexpected advantages.

"Even though it is constructed of silicone, we are seeing much less posterior capsule opacification than we anticipated, and there has been no anterior capsule opacification. There appears to be something magical about keeping the anterior and posterior leaves of the capsule separate from each other," he stated.

Figure 11 A hydrophobic acrylic IOL with a 360 uninterrupted barrier edge (Tecnis 1, AMO) was launched at the 2007 ESCRS meeting. (Photo courtesy of AMO)

Other IOL advances have occurred in Europe. At the ESCRS meeting in September, AMO launched its hydrophobic acrylic IOL with a 360 uninterrupted barrier edge (Tecnis 1), and both Rayner and Acri.Tec,—the latter a part of Carl Zeiss Meditec—have introduced multifocal toric IOLs (M-flex T and Acri.Lisa, respectively), noted Dr. Osher. (Figures 11 and 12).

Figure 12 This multifocal toric IOL (M-flex T, Rayner) allows surgeons to offer multifocality to patients who would otherwise not be good candidates for this technology. (Photo courtesy of Rayner)

"These toric implants represent a huge breakthrough because they allow us to offer multifocality to more patients who would otherwise not be good candidates for this technology," he said.

Figure 13 An IOL in development in Europe (NuLens, NuLens Ltd) offers a huge amplitude of accommodation. (Photo courtesy of I. Howard Fine, MD)

Another lens (NuLens, NuLens Ltd) continues to be in development in Europe and has been reported by Jorge Alio, MD, to have very good results, Dr. Osher said (Figure 13).

Figure 14 U.S. clinical trials of an IOL (Light Adjustable Lens, Calhoun Vision) may get under way soon. (Photo courtesy of Calhoun Vision)

Dr. Fine said he is also very excited about this IOL because of its huge amplitude of accommodation. Dr. Fine, Dr. Osher, and Dr. Olson are all hopeful that the U.S. clinical trials of another IOL (Light Adjustable Lens, Calhoun Vision) will get under way soon (Figure 14).

Dr. Fine said that some very interesting new technology in early development (LiquiLens, Vision Solutions Technologies) contains two immiscible fluids, one with a high refractive index overlying the second with a lower refractive index. On down gaze, the higher refractive index fluid slips forward into the pupillary space to cause an increase in plus power. Another new technology, pixelate optics, is incorporated into a parent IOL; under the influence of an applied electrical charge, the index of refraction can be changed to attain up to +4 D of accommodation.

Putting premium IOLs in proper perspective

As the market for premium IOLs continues to expand, Dr. Olson said he believes it is important to consider the paucity of evidence from peer-reviewed studies proving better patient satisfaction is achieved with presbyopia-correcting IOLs compared with monofocal implants.

"The only studies I am aware of showed that overall satisfaction was the same. Although these premium implants allow patients to see better near, there is a tradeoff with unwanted images and other issues that raises the question of whether it is really a step ahead," he said.

Dr. Olson made it clear that he has not formed an opinion one way or another about the lenses, but believes that active proponents for presbyopia-correcting IOLs need to prove the benefits exist.

"There is no denying that there are some very happy patients, and the opportunity to balance bill for this technology has been an incredible boom that provides reason for optimism about additional products being rolled out in the future," he said. "We can expect the field to get stronger with future entries, but as of now, no studies have withstood the scrutiny of the peer-reviewed process to show higher satisfaction with the premium IOLs."

Merging of cataract and refractive surgery

The merging of cataract and refractive surgery has been under way for some time, but has been fueled in recent years by advances in IOL technology.

"I don't do a cataract procedure now where I am not aiming for refractive precision. Surgeons not targeting the same goal are setting themselves up to deal with unhappy patients," Dr. Olson said. "More and more, I see patients whose expectations are to be spectacle-independent after surgery. The consequences are that more time has to be spent reviewing all the options, and we are also performing more refractive lens exchange (REFLEX)-type procedures in which we are taking out very early cataracts."

Dr. Fine said that the merging of cataract and refractive surgery has caused a shift in practice patterns away from providing high-volume, efficient, low-cost care to delivering high-quality, personalized, patient-paid care. This shift is more evident now than ever before, he said.

"About 35% of our cataract surgery patients opt for a presbyopia-correcting IOL, and based on our longstanding experience, we are very comfortable with this technology. We understand the differences between the various lenses and how to match their features with patient expectations, as well as how to deal with the expectations," said Dr. Fine. "We also are very careful in our preoperative counseling and make sure the patients understand all the pros and cons. However, by and large, we have a large group of very satisfied patients."

He continued, "We see an increasing role for REFLEX and believe it will become the 'bread-and-butter' operation of ophthalmology, superseding LASIK. After all, it is a quadruple win. The patients get every part of their refractive error addressed predictably, and the surgeons win because these procedures are largely independent of government and private insurance, which also allows us to have a less disruptive relationship with our patients. Industry wins because it gets a return on the research investment, and the government is the biggest winner. As more baby boomers opt for REFLEX, the burden of paying for cataract surgery, which is Medicare's highest expense, will go down."

Mixing and matching

With different presbyopia-correcting IOLs offering distinct profiles of vision benefits, mixing and matching has become an often-used strategy for optimizing outcomes. Although Dr. Olson said he believes the concept makes sense, he added that he has not seen much in the peer-reviewed literature to support it.

"Once there clearly is a better mousetrap with the introduction of a really good accommodating IOL, this will no longer be an issue," he stated.

Dr. Fine and colleagues have developed a set of criteria for choosing presbyopia-correcting IOLs that incorporates mixing and matching as needed. Patients who have –3.0 D to –4.0 D of myopia are offered an apodized diffractive lens (AcrySof ReSTOR) with the expectation that they will be able to read without glasses at the same close distance as they did prior to developing cataracts. Computer users are offered either an accommodating IOL (crystalens) or a refractive multifocal lens (ReZoom, AMO). If they are happy with the outcome in the first eye, then they get the same implant in the second eye, or an alternative is selected to address what is missing in their vision.

The refractive multifocal IOL also is a good choice for patients who want a balance of good vision across the entire distance range, they said, adding that tall patients routinely are offered the accommodating lens because it provides excellent intermediate vision.

"For tall people, much of their visual world involves intermediate distances," Dr. Fine said.

The accommodating IOL also is the first choice for those with high myopia. Because it vaults posteriorly, the lens may have a benefit for helping to stabilize the vitreous face in these eyes. In addition, ray-tracing data show that it is a deformable optic, and that feature may have its greatest impact in those with high myopia.

"The optic for the [accommodating lens] powers used in high myopes is relatively thinner and so more deformable. In fact, our best outcomes with this IOL for excellent near, distance, and intermediate vision are in high myopes," Dr. Fine said.

Postoperative endophthalmitis

Postoperative endophthalmitis continues to be a hot topic, with some important new studies published in 2007, including the final outcomes and risk factor analysis from the ESCRS study.

Despite it not being perfect, Dr. Olson applauded Peter Barry, MD, and his ESCRS collaborators for undertaking the first prospective, randomized clinical trial of postoperative endophthalmitis prophylaxis.

"It's easy to take shots at the design, but this was a huge task, and I take my hat off to Dr. Barry and his colleagues," Dr. Olson said.

A study published by Matts Lundstrom, MD, and colleagues in the May issue of Ophthalmology provided support for the findings of the ESCRS trial with regard to the role of intracameral cefuroxime. Although of open-label design, it included 225,000 consecutive patients and showed a dramatic benefit for intracameral cefuroxime.

"If cefuroxime was available in a unit dose preparation, I would be using it now. However, my concerns with using the commercially available parenteral preparation relate to the risks of toxic anterior segment syndrome and instability. Bacterial resistance continues to be a concern as well, although with the high levels attainable with intracameral use, organisms resistant in vitro are likely to be eradicated," Dr. Olson said. "Considering concerns about resistance, it would not surprise me if intracameral antibiotics become the predominant prophylactic technique, especially if a unit dose preparation becomes available."

He added that he was happy to see that the Lundstrom study results did not confirm the findings from the ESCRS study about silicone IOL implantation being a risk factor for endophthalmitis. Rather, in the Swedish trial, the incidence of endophthalmitis was higher with use of an acrylic IOL than with a silicone lens.

For surgeons who have not adopted intracameral antibiotics, Dr. Olson said he believes that adequate evidence supports use of frequent topical antibiotic drops started before surgery and continued through the first postoperative day.

"Beginning antibiotics on the day after surgery is wrong," he said.

Dr. Olson added that interesting studies suggest that subconjunctival antibiotics also may be effective for prophylaxis, although no evidence exists that they are more effective than frequent topical drops started on the day of surgery. Comparing the two, the topical drops clearly have fewer risks and are not painful, he said.

The issue of whether the clear cornea incision has played a role in an increase in endophthalmitis remains controversial, as studies on the topic provide conflicting results, said Dr. Fine.

"In the ESCRS study with more than 16,000 patients, clear cornea incision was a risk factor for endophthalmitis, whereas in a retrospective study from the United Kingdom with more than 100,000 eyes, the rate of endophthalmitis remained stable between 1996 and 2004," he said. "Antibiotic resistance has had an impact on endophthalmitis rates as well. However, in a U.S. study involving nine centers all using a clear cornea incision technique with a fourth-generation fluoroquinolone for prophylaxis, the rate of endophthalmitis was within the usual reported range. And in Sweden, the incidence of endophthalmitis has decreased despite use of the clear cornea incision, but with use of intracameral cefuroxime."

Dr. Fine said that, based on studies using optical coherence tomography imaging to document the profile of the clear cornea incision in the immediate postoperative period, the real issue regarding its role in endophthalmitis risk revolves around whether the incision was properly constructed.

"Clearly, all clear cornea incisions are not the same," he said, noting, "since first introducing this self-sealing incision in 1992, we have used it in more than 10,000 eyes without a single case of endophthalmitis."

Dr. Fine said he also is a proponent for beginning prophylactic antibiotics prior to surgery to achieve levels within the cornea and aqueous and using fourth-generation fluoroquinolones for that purpose. He also pointed out, however, that at the same time endophthalmitis is generating significant attention, cataract surgeons must be careful to not overlook other sight-threatening complications.

"In the Binkhorst Lecture at the ESCRS Congress, Ulf Stenevi, MD, highlighted that other complications of cataract surgery, such as pseudophakic bullous keratopathy or posterior capsular rupture with vitreous loss, can have the same devastating consequences as endophthalmitis, but occur more frequently than endophthalmitis," said Dr. Fine. "These observations are based on solid data from the Swedish National Cataract Registry, where follow-up is complete and no one falls through the cracks."

Dr. Osher said that in a recently completed multicenter study, he collaborated with Dr. Masket and Stephen Lane, MD, to investigate intracameral use of moxifloxacin, injecting 50 L straight out of the bottle into the anterior chamber at the end of the surgery.

"I believe there is a strong rationale for using moxifloxacin as an intracameral agent, and this is an attractive method for its delivery," he said. "According to the most recent ASCRS survey from Leaming and Duffey, 77% of cataract surgeons said they do not use intracameral antibiotics, but 80% said they would if a safe and effective alternative existed."

Figure 15 A new antibacterial eyelid cleanser (SteriLid, Advanced Vision Research) kills 99% of both gram-negative and gram-positive bacteria within 60 seconds when used on lids and lashes, studies show. (Photo courtesy of Advanced Vision Research)

Dr. Osher added that a new antibacterial eyelid cleanser (SteriLid, Advanced Vision Research) may be another useful addition to a prophylaxis regimen (Figure 15). Used on the lids and lashes, studies show it kills 99% of both gram-negative and gram-positive bacteria within 60 seconds.

Other new technology

Dr. Osher ranked new surgical microscopes (Lumera, Carl Zeiss Meditec) as the most interesting technology introduced at the American Academy of Ophthalmology (AAO) annual meeting in November. This equipment features proprietary technology (Stereo Coaxial Illumination) in which the illumination and observation beam paths are fully coaxial. Dr. Osher and Dr. Fine were among a handful of surgeons who had the opportunity to preview the microscopes.

"I have never seen such superb optics or more impressive detail in my life. Looking through this microscope is like having an anatomy lesson," Dr. Osher said.

"The red reflex is outstandingly bright and homogenous, and it stays regardless of the angle or pupil size," he added. "The depth perception is so incredible that it is almost a challenge getting used to seeing in focus from the cornea to the vitreous."

Dr. Fine concurred that the new microscope features spectacular optics, far surpassing anything available to date.

"At first, all of the detail that is visible when concentrating on the focal plane is almost too much information, and so there will be a learning curve for using this technology," he said.

Other new instrumentation is making surgery safer and easier. Alcon will be introducing its D cartridge to enable delivery of its single-piece acrylic lenses through a 2.2-mm incision, and a preloaded insertion system (iSert, Hoya) uses a disposable cartridge and reusable handpiece that can deliver an IOL through a sub 2.5-mm incision.

"With the [preloaded insertion system], lens delivery occurs in a sterile environment without the IOL ever coming into contact with anything foreign," Dr. Osher said. "This type of preloaded system has been long overdue in the United States, and the time has come for other companies to belly up to the bar and develop solutions for avoiding lens handling that only opens the door to problems with contamination and implant damage."

Figure 16 New disposable knives (Atomic Edge, Becton, Dickinson and Co.) are designed to improve surgical safety. (Photo courtesy of Becton, Dickinson and Co.)

New disposable safety knives (Atomic Edge by Becton, Dickinson and Co.) are another welcome product introduction for improving surgical safety (Figure 16).

"I believe all surgeons should have options for minimizing the risk of exposure to infectious diseases," Dr. Osher said.

Honorable mentions

Dr. Osher has designed with Duckworth and Kent new surgical scissors and forceps that can be used at five different angles to allow the surgeon to cut anywhere inside the eye. A new intraocular mirror designed by Bong-Hyun Kim, MD, a South Korean ophthalmologist, is another interesting instrument, as are tools created by Manfred Tetz, MD, for measuring anterior chamber width and facilitating iris enclavation in eyes receiving an iris-fixed phakic IOL.

Also under the heading of innovative new devices is a modification of the 14C Morcher capsular tension ring described by Bonnie Henderson, MD, and colleagues in the October issue of the Journal of Cataract & Refractive Surgery. Its purpose is to enable nucleus and cortex removal while maintaining capsular bag expansion. In addition, a capsular anchoring device designed by Ehud Assia, MD, has been introduced by an Israeli company (Hanita); Dr. Osher described it as phenomenally easy to use.

Dr. Osher said he also is excited about the new color system introduced by Morcher for its artificial iris; it offers 55 options for matching a patient's natural color. In addition, AMO will be introducing a new ophthalmic viscosurgical device ([OVD] Healon D) as the fourth member of its Healon family.

"Now, with the settlement of the lawsuit with Alcon, AMO also will be able to have different OVD carpules so that surgeons can mix and match OVDs for the case," Dr. Osher said.

Pharmaceutical advances

Figure 17 A 1% azithromycin ophthalmic solution (AzaSite, Inspire Pharmaceuticals) approved in 2007 offers fairly broad-spectrum activity with a bioadhesive ocular delivery system designed to enable reduced dosing frequency. (Photo courtesy of Inspire Pharmaceuticals)

In the realm of antibiotics, a 1% azithromycin ophthalmic solution (AzaSite, Inspire Pharmaceuticals) was approved in 2007 (Figure 17). It offers fairly broad-spectrum activity with a bioadhesive ocular delivery system that enables reduced dosing frequency, added Dr. Osher. Indicated for treatment of bacterial conjunctivitis, the recommended dosing schedule is one drop twice daily for 2 days and then one drop once daily for 5 days. It was developed by InSite Vision Inc. and is administered via InSite's patented drug-delivery vehicle (DuraSite).

Based on its activity and minimal dose burden, Dr. Olson said he believes that the formulation will be an important player for treating bacterial conjunctivitis and that it will have a particular niche in the pediatric population. He said he considers it to have too many holes in its antimicrobial coverage to be considered for cataract surgery prophylaxis, however. Because it is bacteriostatic, not bactericidal, this antibiotic will not have a role in treating keratitis, Dr. Olson said.

Figure 18 A fortified levofloxacin preparation (Iquix, Vistakon) containing 1.5% of the fluoroquinolone active ingredient was introduced at the AAO annual meeting in New Orleans. (Photo courtesy of Vistakon)

A fortified levofloxacin preparation (Iquix, Vistakon) containing 1.5% of the fluoroquinolone active ingredient was introduced at the AAO annual meeting in New Orleans (Figure 18).

"This product appears to provide terrific coverage. Substantial data show susceptibility of ocular pathogens to levofloxacin is equivalent to that of the fourth-generation fluoroquinolones," Dr. Osher said.

Formulation with a higher concentration also is the basis for a new once-a-day preparation of bromfenac (Xibrom QD, ISTA Pharmaceuticals).

"The convenience of a once-a-day product makes a lot of sense from the standpoint of patient compliance," Dr. Osher said.

A new paradigm for the future?

In a phase I/II trial, a novel topical agent achieved encouraging results as a potential treatment for cataract. The compound is being developed by Chaksu Research, Los Gatos, CA. It acts by removing heavy metals, has anti-inflammatory properties, and also is being explored for a variety of possible indications in addition to cataract treatment.

"Early clinical trial results indicate that this agent has an effect on reversing nuclear sclerosis, with about 60% of patients showing a 2-line or greater improvement in vision after treatment with the drops. A lot more work has to be done, but I would not rule out that it might offer an option in the future for reversing cataract," said Dr. Olson.