First day of PCON New York meeting highlights glaucoma, AMD, comanagement, IOLs

NEW YORK – Here during the first day of the Fourth Annual Primary Care Optometry News Symposium, our first six presenters covered glaucoma, age-related macular degeneration, perioperative comanagement and IOL selection.

On Friday, Leo P. Semes, OD, FAAO; Robert Wooldridge, OD, FAAO, and Murray Fingeret, OD, FAAO, opened the symposium by discussing diagnostic technology for glaucoma.

A recent study has concluded that the GDx VCC (Laser Diagnostic Technologies), the HRT II (Heidelberg Engineering) and the OCT Stratus (Carl Zeiss Meditec) are all valid for detecting glaucoma. According to Dr. Wooldridge, researchers at the University of California – San Diego looked at the newest versions of these three instruments on the same patient population, which included 107 patients with glaucoma and 76 without.

Dr. Wooldridge said the researchers stated that “The AUCs and sensitivities were similar among the best parameters from each instrument.”

The study was published in the June 2004 issue of Archives of Ophthalmology.

“These technologies are great,” said Dr. Wooldridge, “but they can confuse you. Don’t buy all three; just buy one and make sure you understand it. The learning curve is different on all of the instruments.

“Reimbursement is better than on most of the services we provide,” he added. “The code is the same for all of them, so you can bill for only one.”

At the end of the session, an audience member asked, “Is it really necessary for us to purchase one of these technologies?” “Glaucoma is a very complicated issue,” answered Dr. Wooldridge. “We used to just look at the pressure, then we looked at the field. I know the patient will get damage before I can see it in the visual field. The more information I have the better. I can do it without the technology, but I can do it better with it. I think they’re very valuable. I would hate to go back to the days of not having the technology.”

Dr. Fingeret offered his opinion: “It’s hard to say that imaging technologies are standard of care when many insurance companies will not reimburse for them,” he said. “Unfortunately, this has driven, to a point, what practitioners are doing. The technologies will make things clearer in terms of making a diagnosis -- or not treating people who may just have a large disc.

“The consensus of opinion is changing,” he continued. “These instruments used to be considered experimental. We know that they are helpful. I wouldn’t come out and be aggressive at saying they’re the standard of care. I would say that you need to have some tools to look at the optic nerve well.”

Dr. Semes added: “I don’t think you can manage glaucoma without taking pictures of the nerve.”

Drs. Fingeret and Wooldridge both stated strongly: “Everyone in the room should have a pachymeter in their practice.”

Dr. Semes agreed, adding: “Changes in the lamina cribrosa will be reflected in a thinner central cornea -- another reason for having a pachymeter in your office.”

Dr. Fingeret discussed what he called the “glaucoma continuum” to track the progression of the disease. He said that when the disease is undetectable, the patient will experience ganglion cell death and retinal nerve fiber layer change (RNFL). This then progresses to asymptomatic disease, which involves further RNFL change along with changes in the optic nerve, SWAP visual field, frequency doubling technology and SAP visual field. Once function is impaired, the visual field changes can be moderate to severe and eventually lead to blindness.

Studies have shown that sometimes the optic nerve changes first, sometimes the nerve fiber layer changes first and sometimes they happen at the same time, Dr. Fingeret said. “There’s no doubt that structure change precedes function change,” he said. “When you see visual field loss in a patient, that person has already lost about half of their nerve fiber.”

Dr. Fingeret said the object of diagnostic technology is to detect these changes as early as possible. “Full threshold testing takes too long,” he said. “The hope is that faster tests will become available.”

A new version of SITA SWAP will be available next spring or summer he said. The test will take 3.5 to 4 minutes to run and will narrow the confidence limits.

In a session titled, “What to do when initial glaucoma therapy fails,” Dr. Semes cited a recent study on the effects of adding a prostaglandin to a prostaglandin.

Researchers compared latanoprost alone and travoprost alone to the combination of latanoprost and travoprost in monkey eyes. The combination of the two prostaglandins was found to provide an additional IOP decrease of 2 mm Hg when compared with either drop alone. The study was recently published in the Archives of Ophthalmology.

The meeting runs through Sunday, Nov. 21. Attendees can earn up to 21 continuing education credits.

See the January issue of Primary Care Optometry News for full meeting highlights.