For PACS Eyes, Simple Clinical Exam Enough to Predict Long-Term Glaucoma Risk

— OCT or other modern metrics not required to examine development of main angle-closure suspect

by
Randy DotingaContributing Writer, MedPage Today
January 22, 2024

State-of-the-art metrics are not required to assess the long-lasting threat that asymptomatic clients with main angle-closure suspect (PACS) will continue to glaucoma, information from a Chinese randomized trial revealed.

In 377 clients with PACS eyes, the addition of anterior section optical coherence tomography (AS-OCT) metrics didn’t improve the precision of designs based upon scientific analysis of intraocular pressure (IOP) and main and limbal anterior chamber depths (ACDs) for forecasting the threat of development to main angle closure (PAC) at 14 years, reported Wei Wang, MD, PhD, of Sun Yat-sen University in Guangzhou, China, and coworkers in JAMA Ophthalmology

“By doing a basic scientific evaluation, you can provide the client a forecast about their danger that’s as great as more advanced screening,” James Tsai, MD, MBA, president of the New York Eye and Ear Infirmary of Mount Sinai in New York City, informed MedPage TodayTsai, who penned a commentary accompanying the research study, included that the findings support the possible choice of conservative management of PACS rather of constantly turning to laser peripheral iridotomy (LPI).

Research study co-author David Friedman, MD, PhD, MPH, of Massachusetts Eye and Ear and Harvard Medical School in Boston, described that “PAC is recognized when an optometrist takes a look at the outflow of fluid from the front of the eye (anterior chamber), and the typical location of outflow (the trabecular meshwork) is not noticeable for a minimum of 180 degrees.”

While PAC is connected to angle-closure glaucoma, PACS is a lot more typical, he informed MedPage Today“The primary issue is that PACS will result in glaucoma if left without treatment.”

Wang, Friedman, and associates intended to comprehend whether assessment by means of AS-OCT would enhance predictive designs compared to medical test alone.

“AS-OCT is an imaging method that permits visualization of the angle,” stated Friedman. “Without AS-OCT, the medical professional needs to put a mirrored lens on the eye to image the angle. This can result in distortion and is subjective. AS-OCT permits more quantitative measurements.”

The private investigators taken a look at information from the Zhongshan Angle Closure Prevention (ZAP) research studya single-center randomized medical trial that started in 2008 and tracked 889 clients ages 50 to 70 years who had bilateral PACS and were treated with early LPI in one arbitrarily picked eye. That research study did not support the prevalent usage of LPI as a preventive method, considering that it “showed that extremely couple of individuals detected with PACS ever go on to establish angle-closure glaucoma,” Friedman stated.

For the existing research study, the scientists evaluated information on 377 without treatment PACS eyes, 25% of which advanced to PAC over 14 years; suggest age of the clients at standard was 58 years, and 84% were females.

Adjusted analysis revealed that greater IOP (OR 1.14 per 1-mm Hg boost, 95% CI 1.04-1.25), shallower main ACD (OR 0.81, 95% CI 0.67-0.97 per 0.1-mm boost), and shallower limbal ACD (OR 0.96, 95% CI 0.93-0.99 per 0.01 boost in peripheral corneal density) at standard were connected with 14-year danger of development from PACS to PAC.

A forecast design based upon IPO and ACD measurements revealed “moderate” efficiency (location under the receiver operating particular curve [AUROC] 0.69, 95% CI 0.63-0.75), the scientists reported.

And designs that integrated IOP, main ACD, and either light-room trabecular iris space location (TISA; at 500 μm), light-room angle recess location (ARA; at 750 μm), or dark-room TISA (at 500 μm), showed comparable efficiency:

• Light-room TISA: AUROC 0.70 (95% CI 0.64-0.76)
• Light-room ARA: AUROC 0.70 (95% CI 0.64-0.76)
• Dark-room TISA: AUROC 0.69 (95% CI 0.62-0.75)

Friedman stated the finding that just a 4th of clients established PAC over 14 years “are extremely essential and assistance refraining from doing iridotomy in all PACS eyes.”

“The designs reveal that while we have some capability to forecast who is at greatest threat of getting worse based upon providing attributes, our forecast is not that exact,” he included. “Overall, the truth that shallower anterior chamber and narrower angles are at higher danger supports medical impressions and might lead some with really narrow angles or extremely shallow anterior chambers to choose to have prophylactic iridotomy.”

Progressing, “these findings must motivate those who did refrain from doing so formerly to reevaluate why they do so numerous iridotomies and maybe think about doing less and just on the highest-risk clients,” Friedman stated.

Tsai concurred, keeping in mind that a lot of eye doctors turn “instantly” to the laser treatment in asymptomatic clients even when eye pressure remains in the regular variety, there’s no proof of optic nerve or visual field damage, and the client hasn’t had narrow angle attacks.

He stated these clients can be followed conservatively and informed to prevent drugs that dilate the eye such as antidepressants, the scopolamine spot, non-prescription cold medications, and onabotulinumtoxinA (Botox) injections.

In addition, Tsai stated, eye doctors can reveal clients how to utilize the flashlights on smart devices to reverse narrow angle attacks. The flashlights reverse the condition by activating dilated eyes to restrict, he described.