Phaco turns 50

July 15, 2017

As the ophthalmic community celebrates 50 years of phacoemulsification (phaco) innovation, surgeons and industry alike mark its progress since the inspiration for the procedure came to Charles Kelman, MD, after a visit to the dentist.

Reviewed by David F. Chang, MD; Jack M. Dodick, MD; Richard L. Lindstrom, MD; Samuel Masket, MD; Randall Olson, MD; and Robert H. Osher, MD

As the ophthalmic community celebrates 50 years of phacoemulsification (phaco) innovation, surgeons and industry alike mark its progress since the inspiration for the procedure came to Charles Kelman, MD, after a visit to the dentist.

Phaco may have had its early detractors-but there were some who adapted it early on and eventually helped improve the procedure as it is today. Here are some of their stories and predictions for phaco’s future.

Robert H. Osher, MD, professor of ophthalmology, College of Medicine, University of Cincinnati, and medical director emeritus, Cinncinnati Eye Institute

Dr. Osher recalled being the first resident at the Bascom Palmer Eye Institute, University of Miami Miller School of Medicine in 1978 who performed phacoemulsification, when he was a second-year trainee. His early study and use of phaco made him “extremely passionate” about small-incision cataract surgery.

“Even as a resident, I decided it was the way I wanted to perform cataract surgery,” he said.

Still, the early days of phaco were “always an adventure,” he recalled. Cystoid macular edema was not uncommon, and a torn posterior capsule was a frequent event.

Not unlike Dr. Kelman, Dr. Osher said his own approach to phaco and ways to improve it were usually met with harsh criticism. This included the introduction of astigmatic keratotomy with phaco for the reduction of pre-existing astigmatism, clear hyperopic lensectomy, slow-motion phaco, and the first video symposium to focus on cataract surgery complications. To promote phaco, he introduced the Video Journal of Cataract and Refractive Surgery in the early 1980s.

Dr. Osher credits fellow surgeons and manufacturers for innovative instrumentation, as well as groundbreaking techniques, including capsulorhexis, bimanual surgery, and nucleus disassembly. His own introduction of slow-motion phaco added a way to safely approach more challenging cases, such as the loose lens, the mature lens, and the small pupil. In 2007, he introduced microcoaxial phaco, which is today’s standard.

Dr. Osher’s vision for phaco’s future-and the future of vision-is the elimination of cataracts.

“The scenario is when a patient turns 21, he or she will go see their eye surgeon,” he said. “A clear lensectomy will be combined with an IOL that conquers myopia, hyperopia, astigmatism, and presbyopia.

“Everyone will walk around with crystal-clear uncorrected vision that makes his or her vision beautiful,” he asserted. “I’m 100% certain of this.”

Moreover, the lens implanted in the eye also will be able to measure blood sugar levels, IOP, and even deliver medications, Dr. Osher predicted.

Dr. Osher marvels at how far phaco has come along.

“[The surgery] is so much better now,” he said. It’s such a great operation. People ask about my exit strategy. It’s called death. I love what I do every day. I can’t imagine doing anything more satisfying.”

Excitement and terror

 

David F. Chang, clinical professor at the University of California, San Francisco, and in private practice, Los Altos, CA.

Dr. Chang describes his first phaco in 1982 as a second-year resident at the University of California, San Francisco, as both equal parts excitement and terror.

“The concept of nuclear division and disassembly hadn’t yet been introduced, and therefore most beginning surgeons used one-handed phaco to sculpt away as much of the nucleus as possible,” he described. “This left a thinned-out bowl of nucleus adherent to the posterior capsule, a problem that was coupled with our inability to control or reduce the phaco power with a foot pedal.”

He explained that Dick Kratz, MD, improved the procedure by introducing two important principles.

“The first was bimanual surgery-using a cyclodialysis spatula to tip and then prop the proximal nuclear pole up into the anterior chamber,” he said. “The second principle was to emulsify as much of the nucleus in the pupil plane, equidistant from the posterior capsule and the endothelium.”

Dr. Chang said it is remarkable that Dr. Kelman’s basic concept of a vibrating ultrasound needle with co-axial irrigation and aspiration is still the gold standard for cataract surgery 50 years after he performed the first case.

“Where else in medicine has such a core surgical technology not been supplanted for a period of 50 years?” he asked.

However, he believes that phaco is not the best way to address the growing backlog of cataract blindness in the developing world because of its high capital and per-case costs, the learning curve, rock-hard mature cataracts, and the lack of vitreoretinal surgeons to manage retained nuclei.

“In many developing-world settings, small-incision manual extracapsular cataract extraction [ECCE] is safer and more cost effective for these advanced cataracts in eyes with multiple co-morbidities,” he explained.

Dr. Chang is excited about the potential for manually sectioning a brunescent nucleus with Iantech’s miLOOP as a means of performing a manual ECCE through a much smaller incision without phacoemulsification.

'Beer can' capsulotomy

 

Jack M. Dodick, MD, in private practice in New York City

Dr. Dodick was a third-year resident at Manhattan Eye and Ear in June 1967 when Dr. Kelman did his first phaco. The procedure lasted just under four hours.

“It’s interesting that phaco was not readily adapted until 10 years after its introduction,” Dr. Dodick said.

With time, handpieces-3 lbs. at the time of Dr. Kelman’s first surgery-became smaller and made more efficient. Phaco needles also became smaller, Dr. Dodick said.

“In the early days, a ‘beer can’ capsulotomy was performed, and at times this led to an extension of a radial tear with an unintended opening of the posterior capsule,” he said. “With the advent of capsulorhexis, this complication decreased.”

The introduction of nuclear disassembly techniques, such as chopping and prechop, made the procedure more efficient, faster, and helped to reduce the amount of energy needed.

Among various innovations, Dr. Dodick believes the introduction of viscoelastic material was a major step in further improving safety and efficacy.

“They would assist us by helping preserve corneal endothelium in dense lenses and requiring extended ultrasound time and in short axial length eyes with shallow anterior chambers,” he said. “The use of iris hooks and later other pupillary expanders aided in addressing small pupils and a floppy iris.”

 

Richard L. Lindstrom, MD, adjunct professor emeritus at the University of Minnesota Department of Ophthalmology, and founder and attending surgeon, Minnesota Eye Consultants, Minneapolis

Dr. Lindstrom performed his first phaco in 1977, 10 years after Dr. Kelman performed his first procedure and at a time when fewer than 1% of cataract surgeries were phacoemulsification.

“The equipment was quite primitive compared to today,” Dr. Lindstrom said, describing the careful set-up required and the common occurrence of corneal edema due to corneal endothelium damage that was not yet well understood.

The evolution of techniques and technical advances-including better fluidics, the use of viscoelastic material, and a continuous capsulotomy-all made a difference in phaco’s safety and efficiency, Dr. Lindstrom said.

“We used to have a lot of post-occlusion surge issues that doctors learned how to manage one way or another, and we used a high bottle height,” he said.

The introduction of pulse and torsional phaco, the divide-and-conquer technique, stop-and-chop technique, and nuclear disassembly at or below the iris plane all were major steps for phaco, he noted, while also looking to the future.

“We’re still trying to decide if femtosecond laser-assisted cataract surgery is a mainstream advance,” he said. “It hasn’t crossed the chasm yet to middle adopters.”

However, some handheld methods for anterior capsulotomy intrigue him, as does the idea of lesser use or even no use of ultrasound.

“A lot of surgeons are finding that for many lenses, you can do the procedure with no ultrasound, especially if you disassemble into many pieces,” he said.

“For younger surgeons, ultrasound will go away,” he said. “We’ll probably move away from phacoemulsification to phacoaspiration.”

Tip design

 

Samuel Masket, MD, clinical professor of ophthalmology, David Geffen School of Medicine, Jules Stein Eye Institute, UCLA, and founding partner, Advanced Vision Care, Los Angeles

Like his colleagues, Dr. Masket has seen how advances in fluidics, phaco energy modulation, and phaco techniques have made phacoemulsification a safer and more efficient procedure. Yet another advance he addressed is tip design.

“The original phaco tip was a circular hollow tube that had a straight or slightly beveled angle,” Dr. Masket said. “People have been able to change tip design to allow the surgeon to use the emulsification tip as a surgical tool. As just one example, an angled phaco tip, as it turns out, provides a greater concentration of energy at the end of the tip.”

He went on to describe his 20-plus years of performing bevel-down phaco, which allows the surgeon to impale the nucleus so that the tip is more easily occluded by lens material, facilitating chop and other maneuvers.

However, if Dr. Masket had to pick one advance for the great success of cataract surgery across surgeons and regions, it would be the development of ophthalmic viscosurgical devices (OVDs; viscoelastic material).

“They expand time and space during surgery, while cushioning and protecting ocular structures,” he said. “It’s hard to talk about phaco without talking about what the OVDs have done for the science, and art.” 

He believes the future will include greater use of laser energy although probably not femtosecond laser-assisted cataract surgery as it is used now. Instead, developers may find ways to harness laser energy for more efficient surgery.

Hydrodissection

 


Randall Olson, MD, chairman, Department of Ophthalmology and Visual Sciences, John A. Moran Eye Center, University of Utah, Salt Lake City

When Dr. Olson performed his first phaco in 1975, he said the equipment was archaic by today’s standards.

“Fifty mm Hg was high vacuum, and post-occlusion surge was still scary,” he said. “Many felt 30 mm Hg was as far as you could go. You hand-tuned the instrument, and power was dial-controlled so when you were on, you got all of it instantaneously. No wonder corneas were grossly edematous!”

Three advances within phaco that made a night-to-day difference were recognizing and improving control of post-occlusion surge so the vacuum could be used more safely, linear control of ultrasound power to instantly vary what was needed to the right amount, and ultrasound tip power modulation for improved efficiency, Dr. Olson believes.

He also praised techniques that improved phaco. “Hydrodissection and delineation made it safer,” he said. “Divide-and-conquer was the first major nucleus disassembly breakthrough, followed by chop. Essentially, all else has followed from there.”