The state of the art in cataract surgery

International participants herald the shrinking of the cataract incision and caution that a step forward in IOL technology may equal two steps back.

BySara E. Smith

Because there is so much new information about cataract surgery, Ocular Surgery News convened an international round table to discuss the issue. We gathered together editorial board members from the U.S. Edition, the Europe/Asia-Pacific Edition and the Latin America Edition of Ocular Surgery News.

The topic was cataract surgery, a look at current trends and future developments. Moderator Philippe Sourdille, MD, strove to bring the participants to a consensus on as many issues as possible. The result was an international snapshot of the state of the art in cataract surgery in 2002. A summary of the round table follows here. The full article can be found by clicking here.

As stated by Dr. Sourdille at the beginning of the round table, the purpose of the gathering was to discuss new lens technology, the decrease in incision size, changes in technique and the crucial problems of endophthalmitis and breakdown of the blood-aqueous barrier.

Operative techniques were discussed, including surgical preferences and beginning with anti-infective prophylaxis. The second part of the discussion covered IOL selection.

Anti-infective prophylaxis

The round table participants discussed the role of anti-infective prophylaxis and the possibility and risk of postoperative endophthalmitis.

All the surgeons agreed that immediate postoperative pain and blurred vision are the symptoms of endophthalmitis that patients must be taught to recognize, but ideas on proper treatment and prevention differed.

Controversy regarding the use of antibiotics, such as vancomycin, in the infusion fluid were highlighted. Some participants favored the use of such antibiotics prophylactically because of successful experience, while others objected to their use because of the possibility of increased resistance.

The participants stressed the importance of a good preoperative examination. Ophthalmologists should be on the lookout for blepharitis and lid hygiene problems, and these should be treated before any surgery, they said.

The participants agreed that ophthalmologists must use as many precautions as possible for topical treatment and leave the use of vancomycin in the infusion an open topic. The question has not been answered definitively because of the difficulty of reaching statistical significance in the study of endophthalmitis.

Anesthesia

All participants agreed that general anesthesia is used for certain indications, such as for patients who cannot tolerate topical anesthesia. When called for, total intravenous anesthesia with a laryngeal mask can be used.

Some said they still use local anesthesia by injection in about 5% to 10% of cases because of difficult, unreliable or nervous patients.

All participants said they employ an anesthesiologist in the operating room.

Other topics discussed included the use of lidocaine gel, intracameral anesthesia added to topical anesthesia and the modification of the pH of topical anesthetics.

Incision size, design, location

Participants said clear corneal incision is used in most cases of cataract surgery, with routine incision sizes ranging from 3 mm to 2 mm. Temporal approach with relaxing or limbal incisions if there is astigmatism was also favored by some. Incision size is dependent upon which phaco hand piece is being used, one surgeon said.

Capsulorrhexis

Several surgeons said their technique for performing capsulorrhexis has changed because of use of two-port phaco systems. Additionally, the round table participants agreed that there is a tendency to reduce the size of the capsulorrhexis so it covers the edge of the lens.

Some participants said they prefer to use a cystotome while other prefer forceps when performing capsulorrhexis. Additionally, participants noted the importance of viscoelastic use and the use of capsular dyes, such as trypan blue, in appropriate cases.

Lens removal

Several surgeons said they do not see any advantage in laser removal of cataracts when compared with phacoemulsification. Some said lasers are useful only in the removal of soft cataracts; they have poor irrigation and aspiration systems that cause chamber instability, and increase surgery time.

The group concluded that presently there is no indication for the the use of lasers for cataract removal.

Ultrasound power

Recent improvements in options in lower ultrasound, smaller tips and improvements in fluidics were also discussed.

Control of fluidics is important for techniques such as mechanical nuclear disassembly, participants said. Some companies now have controlled ultrasound delivery at the tip of the probe, one surgeon noted.

Participants concluded that phaco chop is a more capsule-friendly technique than divide-and-conquer, which requires much rotating of the lens. Bimanual phaco helps with cleaning up and removing lens fragments, and utilizing both hands during surgery is not only useful for intraocular maneuvers but also for orienting the eye and for better positioning to treat potential complications.

IOLs

When it comes to the incidence of PCO, ophthalmic surgeons agreed that the design of the IOL was the most significant factor. The second most important factor is the lens material, with third being the surgical procedure, they said.

The posterior edge of the lens is the most vital design aspect for prevention of PCO. For materials, many agreed that hydrophobic acrylic is the best lens, but others stated that a similar level of PCO is seen with either a square-edged silicone or acrylic lens.

There was lack of agreement on the proper evaluation of PCO, how to measure contrast sensitivity and the importance of anterior capsule polishing.

Multifocal, accommodating IOLs

Participants agreed that the multifocal lens has not achieved the results that many hoped for. While most patients are happy with initial results, many have complaints about glare and night vision problems, ophthalmologists said.

As for the promise of accommodative IOLs, participants agreed that they need to learn more about these types of lenses. Initial results appear promising, but if ophthalmologists want to maintain a low rate of capsular opacification, the current state of knowledge about successful IOL designs should be considered.