Extended IOP monitoring may alter treatment for glaucoma patients

Twenty-four-hour monitoring of IOP in advanced glaucoma patients may reveal a greater function for pressure-related risk for glaucoma progression than previously thought, according to a group of researchers.

Robert Ritch, MD, and colleagues at New York Eye and Ear Infirmary and New York University School of Medicine reviewed the records of all glaucoma patients admitted for 24-hour IOP monitoring at the New York Eye and Ear Infirmary. The patients’ applanation IOPs were recorded in the sitting position from 7 a.m. until midnight and in the supine position at 6 a.m. over a three-year period.

The patients were scheduled for the 24-hour monitoring process for a number of reasons, but primarily when the previously recorded IOP no longer explained their current progression of glaucomatous neuropathy. Each of the 22 women and 10 men involved in the study had open-angle glaucoma and was using glaucoma medication upon admission, according to the study.

Of the 32 patients enrolled, the average standard deviation peak 24-hour IOP, 16.8 ± 3.2 mm Hg, was found to be significantly higher than peak office IOP, 14.7 ± 3.2 mm Hg. Measurements for the mean IOP fluctuation and peak IOP levels were also greater than those taken during office hours.

As a result of the 24-hour IOP monitoring, immediate treatment changes were administered to 36% of the patients being tested, the authors said.

Until accurate self-tonometry devices become more readily available, clinicians may consider taking 24-hour IOP measurements for selected patients, the researchers said.

The article appears in the June issue of Archives of Ophthalmology.