Use of ocular sealant may help prevent wound leaks

Take-Home

Assessment for wound leaks should be undertaken in a standardized and quantifiable fashion, and alternative means for wound closure, such as an ocular sealant, should be considered.

By Lynda Charters; Reviewed by Jeffrey H. Levenson, MD

Jacksonville, FL-During the immediate postoperative period, spontaneous wound leaks or those that develop under point-pressure manipulation are prevalent.

Identifying wound leaks is important for preventing associated postoperative complications, and use of an ocular sealant may help prevent wound leaks after cataract surgery, said Jeffrey H. Levenson, MD, in private practice, Jacksonville, FL.

“Although wound leaks have long been known to place [patients with] cataracts at risk for serious complications, their prevalence has never been systematically evaluated,” he said.

In light of this, Dr. Levenson and colleagues at 24 national sites conducted a study to examine spontaneous and provoked wound leaks in 500 prospective patients who had undergone clear corneal cataract surgery.

The investigators performed a Seidel test at the conclusion of each surgery, and spontaneous wound leaks were recorded. In the absence of spontaneous leakage, an ocular force gauge (Ocular Therapeutix) was used to apply consistent and quantifiable force to the ocular surface, Dr. Levenson explained.

Up to 1 ounce of force was applied 0.5 mm from the scleral side of the incision. The incisions were monitored for a positive Seidel test and wound leaks were recorded in 0.25-ounce force increments.

Such seemingly mild force is important, according to Dr. Levenson, who explained that increases in IOP between 27 and 58 mm Hg with light and firm digital pressure have been reported previously (McMonnies CW, Boneham GC. Experimentally increased intraocular pressure using digital forces. Eye Contact Lens. 2007;33:124-129).

In another study, one ounce of pressure was found to elevate the IOP by a mean of 25.95 mm Hg from baseline (Masket S, Hovanesian J et al. Use of a calibrated force gauge in clear corneal cataract surgery to quantify point-pressure manipulation. J Cataract Refract Surg. 2013;39:511-518).

For inclusion in the study, patients had to have undergone an uneventful clear corneal cataract surgery in which a single-plane incision of 3.5 mm or less (no groove) was created. The single plane was defined as extending into the corneal stroma and angled down toward the anterior capsule of the lens. The study eye brought to physiologic pressure.

The vast majority of patients were found to have wound leaks-488 of the 500 study patients.

“Fifty-one percent of the wound leaks were spontaneous,” Dr. Levenson said. With almost one-quarter of the leaks beginning with less than 0.25 ounces of force, the results showed that about 75% wounds leaked spontaneously or with minimal pressure. Almost 97% leaked with less than 1 ounce of force applied.

Other study findings were that the incision sizes, which ranged from 1.8 to 3.5 mm, did not appear to affect the rates of wound leakage. No adverse events occurred in relation to the wound challenge with the ocular force gauge.

Alternative means

A new ocular sealant (ReSure Sealant, Ocular Therapeutix) is a polyethylene glycol hydrogel that is applied as a liquid and becomes a gel after about 20 seconds in situ. The product was designed to protect incisions in the immediate postoperative period. The substance does not have to be removed but sloughs off after re-epithelialization. The FDA has approved the product for use in sealing wounds after surgery.

The product was superior to sutures for preventing wound leaks (4.1% versus 34.1%, respectively, p < 0.0001) in the ReSure Sealant U.S. Pivotal Clinical Trial, Dr. Levenson noted. Significantly fewer adverse events occurred with patients in whom the sealant was used compared with those whose wounds were sealed with sutures (22.7% versus 45.4%, respectively).

In addition, in 94.1% of cases in which the sealant was used, the product was graded as easy or very easy to use. No safety concerns were reported and patients were comfortable overall.

“We found that wound leaks are highly prevalent after cataract surgery,” Dr. Levenson said. “Fluid egress following cataract surgery has been linked to various postoperative complications. Assessment for wound leaks should be undertaken in a standardized and quantifiable fashion, and alternative means for wound closure, such as an ocular sealant, should be considered.”

Jeffrey H. Levenson, MD

E: Jeffrey.levenson@gmail.com

Dr. Levenson has no financial interest in the subject matter. Ocular Therapeutix Inc. sponsored the study.