Cataract surgery innovations highlighted at ASCRS

June 15, 2011

Cataract surgery has emerged as the miracle of 20th century medicine, according to one expert.

"It is the only surgical procedure that rehabilitates function to a level higher than [what] existed before the deleterious effects of aging," said Dr. Fine, clinical professor of ophthalmology, Oregon Health and Science University, Portland, OR.

He touched on the major innovations in cataract technique in the past that have paved the way for where the surgery is today.

Innovations in technology and techniques were continuously forthcoming during the last 30 years of the 20th century, he pointed out, and over the past 45 years, he witnessed implementation of these developments.

Intracapsular cataract surgery was performed with loupes with no intraocular maneuvers. The incisions resulted in a great deal of induced postoperative astigmatism and the coarse sutures could rupture. Many complications could develop and patients required a lengthy hospital stay.

A revolution in cataract surgery occurred when 10-0 nylon sutures were introduced. This strong, inert, elastic suture resulted in unprecedented wound security.

"The greater wound security allowed cataract surgery to be performed as an outpatient procedure, which was less destructive and less costly and ultimately led to the types of advantages that patients and surgeons enjoy in ambulatory surgery centers," Dr. Fine said.

Cataract surgery progressed to more precise microsurgery.

"This facilitated a transfer of skills by devices that could be attached to the microscope and convey exquisite details of surgical maneuvers to large audiences, which in turn resulted in the globalization of ophthalmology," he said.

Extracapsular cataract surgery was popularized with the ability to do cortical cleaning. At this time, other refinements in the cataract technique included small incisions, better IOL support, and segregation of the anterior and posterior segments.

Early phacoemulsification procedures were performed in the anterior chamber, and the fluidics were not well controlled. Many surgeons did not embrace this procedure initially because of the steep learning curve, according to Dr. Fine. Capsular opacification and IOL decentration were common and were addressed, respectively, by YAG laser and the capsulorhexis. Other advances during this period were continuous tear capsulotomy, which facilitates the use of the current premium IOLs; hydrodissection; and techniques of disassembly of the nucleus.

Power modulation was an important step forward in cataract surgery technology. Dr. Fine and his colleagues, who studied power modulations in the late 1990s, optimized the parameters on six machines.

"We got the best results we ever achieved. We documented that the rapidity of visual rehabilitation was inversely proportional to the amount of energy used in the eye," he said. "We were able to remove lenses of all nuclear densities with powers equal to about one-tenth of 1% of that previously reported for continuous phacoemulsification."

Dr. Fine said he believes that technology using a particular system (WhiteStar Signature, Abbott Medical Optics) is the most interesting of the newer modulations, with its micropulses that are shorter than the conduction time of heat and tissue, resulting in cool phacoemulsification.

He introduced the concept of clear corneal tunnel incisions in 1992, the advantages of which were bloodless surgery under topical anesthesia, reduced astigmatism with the temporal approach, and undisturbed conjunctiva. He noted, however, the controversy regarding the safety of the incisions continued because of increased infection rates, but that concern was later dispelled.

New techniques in incision construction, toric IOLs, and LASIK have been used to address pre-existing astigmatism.

"We also have seen improvements in every instrument, device, and substance that we use in cataract surgery," he said. "As a result of these improvements, many surgeons [including] my partners and I have been able to address the most difficult, challenging, and demanding cataract cases, including small pupils, pseudoexfoliation, lost zonular integrity, and decentered lens in fibrosed capsular bags, among others."

Today, more than 9 million patients worldwide undergo cataract surgery through clear corneal incisions annually.

"The patients benefit from less-invasive surgery, freedom from systemic contraindications, negligible surgically induced astigmatism, and for most patients almost immediate visual rehabilitation with excellent uncorrected vision," he said. "Looking ahead 45 years ago, this seemed like an impossibility. Looking back from the perspective of a patient, it is a miracle."

Dr. Fine noted how important ASCRS was in facilitating innovations in cataract, IOL, and refractive surgery and legitimizing them. He also said that marketing, which was once taboo for the medical profession, and marketing forces actually drove surgeons to the best techniques and technologies.

"Marketing enhances and facilitates adaptation of new technology," he said. "Marketing also educates patients."

The future

With the merging of cataract surgery and refractive surgery, the costly femtosecond laser is replacing ultrasound. Dr. Fine believes that the cost obstacle ultimately will be overcome.

"[The] femtosecond laser, with its enormous precision and safety, promises to bring us closer to our unrealized ideal of the perfect cataract procedure," he said. "This will facilitate refractive lens exchange dominating refractive surgery."

He said he believes that ophthalmic practices will face new challenges and need new techniques.

"We are confronted with global epidemics of eye diseases, aging populations, and economic uncertainty, which will create an unprecedented demand for ophthalmology services, and increased access to those services at reasonable costs," he said.

Dr. Fine described a concept taking shape at the Doheny Eye Institute, University of Southern California, Los Angeles. The portable Doheny Diagnostic Device, he explained, will provide ophthalmologists everything needed for testing through electronic patient interactions and comprehensive screening.

"The concept contains already-existing technology, such as self-adjusting lenses, internal light sources, targets, optical coherence tomography, and Internet connections," he said. "Like an iPhone, this device can be a common hardware platform for many diagnostic software applications, including almost all tests that ophthalmologists perform. This is an extremely promising concept."

The miracle of 21st-century medicine, according to Dr. Fine, will be access to cataract surgery by the more than 13 million blind individuals in the Third World.

Dr. Fine concluded by talking about his dream.

"It is a personal and societal tragedy to have someone living in darkness because of a treatable disease," he said. "This will end by replacing itinerant surgeons with teaching centers, so that surgery and training will be done locally by local doctors. Itinerant surgeons will continue to function as advisors."

FYI

I. Howard Fine, MDE-mail: hfine@finemd.com

Dr. Fine did not indicate any financial interest in the topic.

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