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Chicago—Bimanual microincision phacoemulsification offers a number of advantages that make it a better method for lens removal than coaxial phacoemulsification and an especially attractive technique to use in complicated and challenging cases, said I. Howard Fine, MD, in his delivery of the inaugural Charles D. Kelman Lecture at the annual meeting of the American Academy of Ophthalmology.
Dr. Fine's speech, entitled "Technique Ahead of Its Time," was a fitting culmination for the Spotlight on Cataract Surgery 2005 session that was devoted to presentations providing pearls on managing complicated cases and complications.
"When IOLs came into widespread use in the early 1980s, many surgeons said that Kelman phacoemulsification was a technique ahead of its time. However, some of us persisted because we thought it was a better way to remove a cataract," explained Dr. Fine, clinical professor of ophthalmology, Oregon Health & Science University, Portland. He is also a founding member of the Oregon Eye Associates and in private practice in Eugene with Drs. Fine, Hoffman & Packer. "Bimanual microincision phacoemulsification is a better method for cataract removal too. Not only does it further reduce incision size, but by separating infusion from aspiration, it gives us unique fluidics advantages that are especially appreciated in the types of complicated and challenging cases that were the subject of today's symposium."
He presented a series of intraoperative videos from challenging cataract cases to demonstrate the benefits derived from separating infusion from aspiration. In addition, Dr. Fine presented case illustrations of where the opportunity to switch instruments between hands was helpful in safely and efficiently completing difficult procedures. His lecture also highlighted situations benefiting from the unique advantages of microincision instruments.
Using the example of an eye with high myopia, Dr. Fine demonstrated how his technique for bimanual microincision phaco enables safe and controlled lens removal in the posterior chamber while keeping the eye pressurized throughout the procedure to minimize trampolining of the vitreous base. He also demonstrated the efficiency and safety benefits of bimanual microincision phaco in eyes with a mature cataract and zonular dialysis, a posteriorly subluxated cataract, and an intraoperative posterior capsule rupture.
"These procedures might have resulted in a number of complications and disastrous visual outcomes, but all could be completed in an unhurried manner using pedestrian surgical maneuvers and the fluidics advantages of bimanual microincision phaco. Patients achieved excellent uncorrected visual acuity," he said.
In another video clip, Dr. Fine demonstrated how the ability to switch instruments between hands helped in avoiding stress on residual zonules in an eye with a superior traumatic zonular dialysis. In that case, the intraocular contents were being pulled toward the phaco tip in Dr. Fine's right hand, causing tension on the attached zonules to the left. Therefore, he switched hands to use the phaco tip in his left hand and the irrigator in his right.
In an eye with microcornea and iris coloboma, he highlighted the advantage of using the micro-handpieces developed for bimanual microincision phaco.
"In contrast to the 3-mm coaxial instruments, the micro-handpieces enable working in the confined space available in such eyes without indenting the cornea and compromising visualization of intraocular structures," Dr. Fine said.
In another eye with persistent microhyphema after pupil stretching, a microirrigator and microcautery tip were used in stepwise fashion to identify and cauterize the bleeding points precisely, while in another case, the microincision instruments were shown to greatly facilitate intraocular pupilloplasty in an eye with an extremely fragile and atrophic iris.
Improved instrumentation
Dr. Fine demonstrated the use of a microincision capsulorhexis forceps and noted that it is a particularly effective tool in eyes where there is zonular damage or a partially subluxated lens.
"This instrument can be used to create a very precise capsulorhexis principally because it is oarlocked through the 1-mm incision. The surgeon must rely on the fingers rather than the wrist to use the forceps. In addition, the bimanual microincision technique is helpful in these eyes because it prevents egress of viscoelastic during capsulorhexis and therefore fluctuations of the anterior chamber," Dr. Fine said.