Gatifloxacin promotes fast wound healing, may reduce infection rate

Zymar may help reduce endophthalmitis after the larger-incision surgery necessary for some new refractive IOLs.

Issue: May 15, 2006

ByErin L. Boyle

Paul J. Dougherty, MD [photo]
Paul J. Dougherty

Gatifloxacin can assist in achieving successful refractive lens surgery by preventing infections in younger patients, according to Paul J. Dougherty, MD.

Dr. Dougherty, a refractive surgeon, said in a telephone interview with Ocular Surgery News that the fluoroquinolone Zymar (gatifloxacin ophthalmic solution 0.3%, Allergan) has excellent biocompatibility for use in refractive surgery. He said it promotes healing and does not irritate the eye. He has performed perioperative prophylaxis using gatifloxacin as a preoperative antibiotic in 2,000 patients and has not had a case of endophthalmitis, he said.

“If you have a medication that is less biocompatible and therefore slows wound healing, you increase the chance of a wound leak, which can lead to the entry of bacteria into the anterior chamber and the development of endophthalmitis,” Dr. Dougherty said.

Infections

There are two ways for an infection to start as a result of intraocular surgery, according to Dr. Dougherty: introduction of an organism on an instrument during surgery or through an unhealed wound postoperatively. He said rapid wound healing, eliminating the potential for infection, is key.

“In choosing a perioperative antibiotic for these newer lenses, you have to pay attention to both efficacy … and biocompatibility as well,” he said.

Dr. Dougherty said he performs several types of refractive lens surgery. He performs refractive lens exchange with implantation of the Advanced Medical Optics ReZoom multifocal IOL, the eyeonics crystalens accommodating IOL and the Lenstec Tetraflex accommodating IOL (under an FDA investigational device exemption). He also implants the AMO Verisyse and STAAR Visian ICL phakic IOLs.

“The patient coming in for presbyopic lens exchange is generally much younger than the standard cataract patient,” he said. “The bottom line is, they are coming in with good best corrected vision, they want to have surgery, and they want to minimize risk. Doing intraocular surgery, the biggest fear is the fear of developing endophthalmitis, which is typically a very devastating complication. We’re trying to avoid that. So when I look at a perioperative antibiotic, I look at something that is not only efficacious but is also biocompatible, to help minimize risk of endophthalmitis.”

He cited studies by Peter J. McDonnell, MD, that looked at the occurrence of wound leaks after clear corneal cataract surgery. They showed that infections could occur after intraocular surgery not only because instruments are introduced to the eye, but also because material can travel from outside the eye to inside the eye until the wound heals, Dr. Dougherty said.

“Basically, the wound can suck bacterial products from outside the eye to inside the eye,” he said. “This is actually a process that [goes on] longer than previously believed, particularly with sutureless surgery, which many of these surgeries are.”

Prophylaxis

Dr. Dougherty said some of the new refractive lenses have characteristics that make antibiotic prophylaxis important. The Verisyse, for instance, requires a 6-mm superior incision, twice the size of the 3-mm incision that cataract surgeons usually use. This raises the problem of slower wound healing and the potential for induced against-the-rule astigmatism, he said.

Another new IOL for which effective prophylaxis could be important is the crystalens, Dr. Dougherty said. He said the lens moves back and forth in the capsular bag during accommodation. “If you have a medication that is less biocompatible that slows wound healing, you increase the chance of a wound leak, which can lead to anterior vaulting of the lens and induced myopia during the early postoperative period,” he said.

New generation

An important step toward accommodating the combination of new refractive IOLs and younger refractive patients with good best corrected vision is switching to the latest generation of anti-infectives, Dr. Dougherty said. He said the main reasons for the switch from the older generation of fluoroquinolones to the newest generation of fluoroquinolones are resistance and efficacy issues with older generation antibiotics. The internal medicine and family practice community often prescribed oral fluoroquinolones, creating a tremendous amount of antibiotic resistance to earlier generation fluoroquinolones, especially with gram-positive organisms, he said.

“The rate of antibiotic resistance and endophthalmitis with gram-positive bacteria has gone up tremendously in the last few years,” Dr. Dougherty said. “In terms of minimization of endophthalmitis with the newer fluoroquinolones, I think that Zymar has excellent gram-positive coverage and has a little bit of an edge regarding gram-negatives and atypical organisms compared to other newer fluoroquinolones.”

For more information:

Paul J. Dougherty, MD, is a clinical instructor of ophthalmology at the Jules Stein Eye Institute at the David Geffen School of Medicine at UCLA. He can be reached at Dougherty Laser Vision, 321 N. Larchmont Blvd., Suite 1020, Los Angeles, CA 90004; 323-466-7337; e-mail: info@doughertylaservision.com; Web site: www.doughertylaservision.com. Dr. Dougherty is a consultant for Allergan.

Allergan Inc., maker of Zymar (gatifloxacin ophthalmic solution 0.3%), can be reached at P.O. Box 19534, Irvine, CA 92623; 714-246-4500; fax: 714-246-4971; Web site: www.allergan.com.

References:

McDonnell PJ, Taban M, et al. Dynamic morphology of clear corneal cataract incisions. Ophthalmology. 2003;110(12):2342-2348.

Taban M, Rao B, et al. Dynamic morphology of sutureless cataract wounds - effect of incision angle and location. Surv Ophthalmol. 2004;49 Suppl 2:S62-72.

Erin L. Boyle is an OSN Staff Writer who covers all aspects of ophthalmology.