EyeWorld is the official news magazine of the American Society of Cataract & Refractive Surgery.
Issue link: https://digital.eyeworld.org/i/78716
March 2012 Dr. Noecker believes that of the three diagnostic methods, gonioscopy requires the most skill to identify landmarks properly. "At a minimum, it requires the applica- tion of an anesthetic drop to the cornea and if a patient is a squeezer, it can be difficult. I sometimes use a three mirror or Koeppe lens in those patients, but it can be a little messy and requires the use of a coupling agent like hydroxypropyl methylcel- lulose or other viscous agent," Dr. Noecker said. "Press very lightly when you perform gonioscopy," Dr. Rhee sug- gested. "If you push hard, you get all kinds of striae on the cornea and can obscure the view. Once you're on the eye, gently move it up and down or back and forth; you're an- gling the mirror to get a better view." Role for anterior segment OCT and UBM Despite the praise for gonioscopy, these specialists still see a diagnostic role for newer imaging modalities, particularly UBM. "UBM is nice because it can pro- vide imaging behind the iris so that secondary causes such as plateau iris or iris cysts can be confirmed," Dr. Noecker said. However, it is the least comfortable for the patient and pro- vides a lower resolution image than OCT, he said. Dr. Rhee uses UBM in a similar fashion. "I use UBM when I'm suspi- cious of pathology in the ciliary body," he said. OCT is fast and provides high- resolution images, Dr. Noecker said. "The newer features are faster imag- ing time, better patient comfort, and higher-resolution images compared to older versions," he said. The im- aging can help patients understand their own anatomy better and help to document how much opening of the angle there may have been fol- lowing a laser or other procedure, he added. Still, "OCT is nice as a screen and is patient friendly but provides less information on structures be- hind the iris," Dr. Noecker said. He likes to use these two technology types as confirmatory tests to see if they correlate with gonioscopy find- ings. He does not think they substi- tute for a good gonioscopic evaluation. "If I had a question about a diagnosis, I might use OCT, but gonioscopy would still be the focus," Dr. Herndon said. Dr. Rhee believes that anterior segment OCT has great research po- tential but is not the best method in his hands to diagnose angle-closure glaucoma. "A lot of people doing re- search are finding that the angles are much more narrow on anterior seg- ment OCT than gonioscopy," Dr. Rhee said. "I think that's virtually valueless. I'm under the impression that once a patient has gonioscopy and is under the care of an ophthal- mologist, it's highly unlikely that narrow-angle or acute-angle glau- coma will go undiagnosed. I don't disbelieve other findings, but I don't think they are clinically relevant." In the future? Although anterior segment OCT and UBM have utility in cornea, research, and other aspects of glau- coma, these physicians don't believe they will become standouts in angle- closure glaucoma soon. Some physicians may choose to use them if patient volume is a con- cern, as technicians can perform screenings with the technology in- stead of physicians performing the gonioscopy, Dr. Rhee said. Of course, that comes with an increased cost. Adding the technology may increase time and space as they are added to the exam lane, and users must plug in paper data, Dr. Herndon said. EW Editors' note: The doctors mentioned have no financial interests related to this article. Contact information Herndon: 919-684-6622, herndo12@duke.edu Noecker: 412-647-2152, noeckerrj@gmail.com Rhee: 617-573-3670, dougrhee@aol.com Serving Eye Care Professionals since 1982 Discover the USB Ultrasound dvantages of (800) 722-3883 www.dghkoi.com A Portable USB A-Scan Actual size: 5.75" X 3.5" U Contact and Water Immersion Modes U Multiple IOL Formulas, including Post-Refractive U Customizable, Professional Reports U EMR/EHR Compatible Visit Us at ASCRS Booth #1623