Gonioscopy underused, analysis of Medicare records suggests

Medicare eye care providers are not performing gonioscopic exams as frequently as recommended before glaucoma surgery, a study suggests. The underuse is of particular concern in patients undergoing laser iridotomy, the study authors said, because gonioscopy is the test of choice in angle-closure glaucoma.

Anne L. Coleman, MD, PhD, of Jules Stein Eye Institute in Los Angeles, and colleagues reviewed data for a 5% random sample of Medicare beneficiaries who underwent surgery in 1999 for open-angle glaucoma, anatomic narrow angle or angle-closure glaucoma. The American Academy of Ophthalmology's Preferred Practice Patterns for angle-closure and open-angle glaucoma recommend bilateral gonioscopy at initial presentation and then at least every 5 years after that.

The researchers found that gonioscopy exams were performed in 49% of patients in the 5 years before they under went glaucoma surgery.

Patients with open-angle glaucoma had a significantly lower examination rate of 46% compared to 58% for patients with anatomic narrow angle and 57% for patients with angle-closure glaucoma (P < .001), according to the study authors.

The rate of gonioscopy exams was significantly higher for Hispanic patients, elderly patients, patients undergoing laser iridotomy and patients receiving care in the New York/New Jersey area (P < .05).

The study is published in the December issue of the Journal of Glaucoma.