Laser peripheral iridotomy (LPI) increases angle width in all stages of primary angle closure (PAC) and is relatively safe, according to Sunita Radhakrishnan, MD. The findings are drawn from a recent Ophthalmic Technology Assessment published in Ophthalmology.
“It’s not so much a controversial topic as much as it hasn’t been updated in a long time,” Dr. Radhakrishnan said. The last OTA on the topic was done in the 1980s. “In this update, we wanted to look at the outcomes and efficacy after laser iridotomy.”
Dr. Radhakrishnan described the OTA committee’s findings in a session at AAO 2018 titled, “A Critical Evaluation of Top-Line Data: Glaucoma Papers That Will Change Your Practice.”
The authors reviewed 36 studies, including 6 with level I evidence, on the efficacy and complications of LPI in patients with PAC.
Their analysis revealed that between 2% to 57% of patients have persistent angle closure after LPI. Patients with a narrower angle, a thick iris, an anteriorly positioned ciliary body, or a greater lens vault were more likely than others to develop PAC.
The OTA states that people who benefit the most from the procedure don’t have extensive preexisting angle or disc damage. Bleeding occurred in a number of eyes but was typically minor. Spikes in intraocular pressure (IOP) occurred in up to 64%, while dysphotopsia occurred in up to 11% of eyes. Cataract progression occurred in up to 40% of patients over follow-up periods of 1 to 6 years.
The few studies that examined progression to glaucoma after LPI suggest that such progression is not common among people with suspected or diagnosed PAC. However, patients with PAC and acute PAC—and particularly those with PAC glaucoma—are far more likely than those with suspected PAC to need additional treatment to control IOP.
Most participants were Asian, she noted, so the results may not be generalizable to other populations. Given that caveat, the findings suggest that patients should be carefully monitored for IOP elevation and progression after LPI.—Anni Griswold
Financial disclosures. None
Next story from AAO 2018—Panelists Name 2018 Best Original Papers: Expert panels named the papers that they rated most highly this year.