January-February 2020

CATARACT

Skill focus
Keys to sealing phaco corneal incisions


by Rich Daly Contributing Writer


ReSure Sealant on the eye at the time of surgery. The sealant has a blue color that disappears in 1 to 2 hours, and it is also visible with fluorescein staining.

ReSure Sealant is visible on the eye one day after
surgery when stained with fluorescein.
Source (all): John Hovanesian, MD

 

EyeWorld is introducing a new column to run in addition to the Device Focus and Pharmaceutical Focus columns. The Skill Focus column will take a look at specific procedures and techniques, offering expert insights and pearls for perfecting this skill.

Surgeons continue to evolve their approach to creating and sealing corneal incisions for cataract surgery.
The main component to creating a well-sealed incision is the wound architecture used by the surgeon, said John Hovanesian, MD.
Surgeons commonly use either a two- or three-plane incision.
The straightforward two-plane incision includes a cut from the limbus in the clear cornea toward the central cornea progressively becoming deeper as the blade advances and tilting it posteriorly near the end of the cut to form a second plane in the incision. The approach effectively creates an internal valve that closes.
In the three-plane technique, before making the incision through the cornea, a vertical cut is made near the limbus to obtain depth in the cornea. In the deepest part of the incision, the blade advances toward the central cornea and creates a second then third plane.
“Those can both work well,” Dr. Hovanesian said. “Generally, you want to have a little bit of length in the incision so that provides a greater valve size, and it provides a mechanical advantage for intraocular pressure to close the wound.”
Kendall Donaldson, MD, who uses a blade to create a three-plane incision, used to use a femtosecond laser to create incisions.
“However, I later reverted to using a blade to make my primary incisions during femto cases, as the femto wounds were a little more difficult to close,” Dr. Donaldson said.

Causes of leaking wounds

Dr. Donaldson checks for wound leakage postop with a Weck-Cel sponge.
“Typically, that is all that is necessary, as I can visualize any leakage from the wound,” Dr. Donaldson said.
Common causes of leaking incisions include wounds that are too short, wounds with irregular edges, and longer surgical cases associated with increased manipulation and distortion of the wound.

When incision closure help is needed

Routine cataract cases rarely require extra help sealing an incision, but if a patient has vitreous loss or a history of endophthalmitis in the other eye, Dr. Donaldson always places a suture.
Other patients who can benefit from postop incision sutures include:
• Patients with continued leakage from the wound or thinning of the cornea at the limbus;
• Patients with a history of radial keratotomy (RK); and
• Patients with severe intraoperative floppy iris syndrome (IFIS).
“If there is a small amount of leakage in these patients, the iris may become incarcerated in the wound causing a peaked pupil and increasing the risk for cystoid macular edema,” Dr. Donaldson said about severe IFIS patients.
When using sutures, some surgeons bury the knot, but Dr. Hovanesian usually doesn’t because he removes the 10-0 nylon 1 day postop.
“Usually the epithelium is sealed over the outside of the incision in 1 day, if you use the suture,” Dr. Hovanesian said. “At that point, the incision is more or less leak-proof.”

Using surgical glue

Another wound sealing option is the ReSure Sealant (Ocular Therapeutix), which is FDA approved for cataract wounds. The hydrogel material is designed to be painted on an external wound at the end of surgery, dissolving and hydrolyzing over several days to provide time for the wound to self-seal.
“The material is easy to use, it can be stored in the operating room for months, and is clinically proven to work better than sutures at sealing incisions,” said Dr. Hovanesian, who served on the clinical trials for the sealant.
He said the trials compared wounds that were sutured with those that were closed with ReSure. They found that the wounds closed with the sealant were more resistant to external compression.
“Because of the cost of ReSure, it may not be for every cataract surgery, but it is a product that should be available in every operating room because a variety of complications can occur during surgery that make a wound very hard to seal,” Dr. Hovanesian said.
Cases that could benefit from the sealant include wound burns, pre-existing incisions (like those from RK), trauma cases, and irregular corneal incisions. There are certain types of patients who can benefit from use of a sealant as well, Dr. Hovanesian said. They include patients with poorly healing wounds, such as those with diabetes; those unlikely to take their drops; those prone to touching their eye; those prone to complications if wound leak were to occur (such as patient with IFIS or pseudoexfoliation); and patients receiving an accommodating IOL where wound seal can help ensure a good refractive outcome.
ReSure is packaged as two dry components and a liquid activator in a dropper bottle. The surgeon places two drops of the liquid into the activator and mixes it with the white hydrogel material for about 5 seconds. The mixture is then applied to the surface of the wound where it will polymerize.
Dr. Hovanesian noted that wounds need to be dry before the sealant is applied.
“If it is actively leaking at the time, it is like trying to put paint on a surface that has a leak coming through it,” Dr. Hovanesian said. “It doesn’t work well.”
Lowering the pressure in the eye can reduce leaks and provide the 30 seconds it takes for the sealant to polymerize.

About the doctors

John Hovanesian, MD
Clinical assistant professor
UCLA Jules Stein Institute
Los Angeles, California

Kendall Donaldson, MD
Medical director
Bascom Palmer Eye Institute
Plantation, Florida

Relevant disclosures

Hovanesian: Ocular Therapeutix
Donaldson: Alcon, Bausch + Lomb, Johnson & Johnson Vision

Contact

Donaldson:
KDonaldson@med.miami.edu
Hovanesian: jhovanesian@harvardeye.com

Keys to sealing phaco corneal incisions Keys to sealing phaco corneal incisions
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