Healon5 improves control over intraocular environment during cataract surgery

In most cases, the entire chamber remains filled with viscoelastic throughout the procedure.

Issue: June 15, 2003

ByBob Kronemyer

WAILEA, Hawaii – Surgeons can significantly improve their ability to perform precise and safe cataract surgery by using an adaptive viscoelastic, according to a speaker here.

Technique tip

Because Healon5 effectively neutralizes positive pressure, the surgeon will occasionally observe a tendency for the anterior chamber to collapse once the ophthalmic viscosurgical device is removed, said Robert H. Osher, MD.

“For positive pressure, I always take my foot off the pedal when I finish evacuating the Healon5, but I don’t remove the I&A tip,” he said.

In cases of positive pressure and a chamber that starts to shallow, Dr. Osher places a cannula through the second (stab) incision to restrain the optic. He also injects Miochol (acetylcholine chloride, Novartis Ophthalmics) as the I&A tip is removed.

In rare instances of malignant positive pressure, when it is unsafe even to insert the silicone I&A tip to begin the Tetz technique, Healon5 can be removed with a 27-gauge cannula through the second stab incision without disturbing the main incision by using a push-pull manual I&A technique, Dr. Osher said.

Robert H. Osher, MD, said Healon5 (sodium hyaluronate 2.3%, Pfizer) can be beneficial for use in eyes with relatively small or mid-sized pupils. Dr. Osher, a professor of ophthalmology at the University of Cincinnati College of Medicine and medical director emeritus of the Cincinnati Eye Institute, spoke on the subject here at Hawaii 2003: the Royal Hawaiian Eye Meeting.

“Healon5 permits exquisite control of the intraocular environment, with maximum protection, visibility and removability,” said Robert H. Osher, MD. He said that using his technique, the ophthalmic viscosurgical device (OVD) remains in the anterior chamber throughout phacoemulsification (performed beneath a protective block of the OVD). Viscomydriasis and the neutralization of positive pressure are additional benefits, he said.

“Viscomydriasis, in particular, is something none of us expected. It may be minimal or dramatic, but mechanical dilatation is always helpful. There is no question that pupil size correlates to ease of surgery,” he said. Even in a large pupil, mild dilation still occurs, he added.

Dr. Osher said he has been using Healon5 for the past 5 years.

Capsulorrhexis

Dr. Osher said he has discovered that by filling the entire chamber with Healon5, the capsulorrhexis has no tendency to run peripherally.

“A ‘designer’ rhexis can be created to allow any shape or size because the capsule is suspended in this frozen, solid-state surgery,” he said. “The capsulorrhexis technique requires a bit of practice because there is a greater resistance of the viscous Healon5 regardless of the chamber depth that the surgeon selects.”

If a capsular dye is desired, Dr. Osher injects a stream of saline directly onto the anterior capsule, followed by the literal “painting” of the capsule with the dye beneath the Healon5.

During hydrodissection, he prefers to let the Healon5 “belch out,” if it chooses to do so, by depressing the lower lip of the incision with the cannula.

“This is a good technique because it does not stress the zonules. But the most important reason that I want the viscoelastic to escape is because it is has been diluted and fractured, which would make it more likely to come out during the emulsification,” he said.

Phaco

Prior to phacoemulsification, Dr. Osher reinjects fresh Healon5 fully into the chamber.

“Then I can perform phaco underneath the cast of viscoelastic, remote from the cornea. The chamber remains stable,” he said.

Phaco is begun using 250 mm Hg of vacuum.

“This ensures good exchange at the tip and prevents thermal injury, which is more likely to occur as viscosity increases,” he said. The aspiration rate is maintained at 25 cc throughout phaco, and the bottle height is relatively low to reduce turbulence.

The ultrasound needle delves directly into the lens, sculpting three quick passes throughout the anterior cortex and nucleus.

Once a vertical trough has been created, the vacuum is reduced to 30 mm Hg and maintained during the last several passes through the deeper nuclear layers.

The nucleus is then divided into halves and rotated 90°. The vacuum is increased to 170 mm Hg for chopping and effective quadrant management with NeoSonix (Alcon). The remaining nuclear hemisphere is rotated 180°, chopped and removed in the same safe manner. Residual epinucleus is aspirated and emulsified.

“In 99% of cases, the entire chamber is still full of viscoelastic,” Dr. Osher said. Cortical removal is accomplished by either engaging the cortex under the Healon5 or removing it after the OVD has been aspirated.

IOL implantation

Although there are concerns that the increased viscosity of Healon5 may interfere with IOL implantation, Dr. Osher said he has yet to encounter any interference with the injection or insertion of any acrylic or silicone lens.

“In fact, Healon5 is wonderful for the lens because it keeps the IOL in a smaller profile,” he said. “For acrylic lenses such as the AcrySof (Alcon), the viscoelastic makes it easy to maneuver with such gentle and controlled unfolding of the haptics. For silicone lenses, the Healon5 just cushions the explosive opening of the lens. Any intraocular gymnastics required with the IOL are greatly facilitated with Healon5.”

To remove the Healon5, Dr. Osher prefers the Tetz two-compartment technique, in which the lens is gently decentered and the silicone irrigation and aspiration tip is maneuvered behind the optic into the capsular bag. Then, with the port anterior, the Healon5 is easily evacuated from the capsular bag with higher I&A vacuum settings.

After the bag is empty, the lens is recentered with the silicone I&A tip, and the Healon5 is removed from the posterior and anterior chambers respectively.

For Your Information:

Robert H. Osher, MD, can be reached at the Cincinnati Eye Institute, 10494 Montgomery Rd., Cincinnati, OH 45242; (513) 984-5133; fax: (513) 936-4881; e-mail: rhosher@cincinnatieye.com. Dr. Osher has no direct financial interest in any product mentioned in this article. He is a paid consultant for Pfizer and Alcon.

Pfizer, maker of Healon5, can be reached at 100 Route 206 North, Peapack, NJ 07977; (908) 901-8592.