Cataract surgery yields improved vision in wet AMD without need for increased treatment

A study compared visual and anatomic outcomes in AMD patients who underwent cataract surgery vs. those who did not.

Issue: December 10, 2015

Cataract surgery improves visual acuity without worsening wet age-related macular degeneration in patients receiving anti-VEGF injections, according to a study.

In the aging population, patients with wet AMD also commonly develop significant cataracts, and there is concern that inflammation and IOP fluctuations that accompany even uncomplicated cataract surgery may exacerbate the condition, necessitating more frequent or changing anti-VEGF treatments and the risk of diminished visual acuity.

The retrospective study evaluated the visual outcomes and potential complications of cataract surgery in patients under treatment for wet AMD, with the aim of adding evidence to the current literature to help in the decision making of whether to proceed with the surgery in these patients.

“For the control group, we looked at a single calendar year’s worth of patients receiving anti-VEGF injections who did not get cataract surgery centered at a midpoint of the year, which is July 1. We analyzed the first 6 months of the year and the second 6 months of the year from a randomly selected total sample matching the number of patients in our actual interventional study group,” senior and corresponding author Michael D. Ober, MD, told Ocular Surgery News.

Improved vision

Forty consecutive eyes underwent cataract surgery at the midpoint of 1 year vs. 42 eyes treated with anti-VEGF injections that did not undergo surgery. Under a treat-and-extend protocol, eyes were typically treated with three consecutive monthly injections, and then treatment was extended based on OCT and fundus examination findings.

Three months before the 1-year midpoint, mean best corrected visual acuity was 20/89 in both groups. Three months after the midpoint, mean BCVA improved to 20/53 in the surgical group and 20/69 in the non-surgical group.

There was no difference in the number of injections before and after surgery in the surgical group, but the number of injections decreased from 3 ± 1.45 injections before the midpoint to 2.57 ± 1.45 injections after the midpoint in the non-surgical group.

Ober attributed the lack of reduction in injection frequency after surgery to the tendency to be conservative with extending treatment intervals in the perioperative period. The study also showed an increased retinal thickness after surgery, which would prompt a treating physician to either maintain or reduce the treating interval rather than increase it.

“Those things probably contributed to a stable injection frequency, which is likely beneficial,” Ober said. “With few exceptions, notably aflibercept bimonthly, most studies comparing anti-VEGF injection protocols have shown less visual gain with a reduced injection frequency compared to more frequent treatment.”

Subclinical findings

There was no significant difference in initial central retinal thickness (CRT) between the groups as measured by OCT. Surgical eyes had a greater final CRT of 265.4 ± 98.4 µm compared with 216.4 ± 58.3 µm in non-surgical eyes.

Surgical eyes also had a significantly greater number of new or worse cysts after the midpoint: 13 eyes in the surgical group vs. nine eyes in the non-surgical group.

Ober recommended closer monitoring for cystoid macular edema or choroidal neovascularization in the 3 months after cataract surgery in patients with wet AMD.

When deciding whether to proceed with cataract surgery, Ober said the procedure should be performed only in patients with stable wet AMD.

“If the patient with visually significant cataract has well-controlled macular degeneration, meaning there is no subretinal fluid or inter-retinal cystic changes, they are a very good candidate for cataract surgery, even if they need ongoing anti-VEGF injections to maintain that state,” he said.

For further studies, Ober would like to focus on the increased retinal thickness seen in the surgical group.

“The more patients who are studied, the better of an idea we will have about the effect of cataract surgery on those with wet macular degeneration,” he said. “Certainly I would like to further analyze the OCT thickness for those before and after, and I would like to have angiography to see if I can differentiate postoperative CME from CNV as a cause of the increased thickness we found.” – by Kristie L. Kahl

Reference:
Saraf SS, et al. Am J Ophthalmol. 2015;doi:10.1016/j.ajo.2015.06.006.

For more information:
Michael D. Ober, MD, can be reached at 29201 Telegraph Road, Suite 606, Southfield, MI 48034; email: obermike@gmail.com.

Disclosure: Ober reports no relevant financial disclosures.