Lens Replacement in Angle Closure Glaucoma Safer Than Filtering Surgery

Lens replacement in angle closure glaucoma (ACG) is safer than filtering surgery for patients younger than 40 years of age, according to a study published in the American Journal of Ophthalmology. Both procedures resulted in significant but comparable intraocular pressure (IOP) and drug reductions.

The study authors aimed to establish the role lens replacement could play in angle closure treatment of patients younger than the participants of the Effectiveness of early lens extraction for the treatment of primary angle-closure glaucoma (EAGLE) trial, which only enrolled patients aged 50 years or older.

The researchers analyzed data from 130 participants (160 eyes) younger than 40 years of age who had undergone filtering surgery or lens extraction for ACG. Of the patients who received filtering surgery, 76 had primary angle closure glaucoma (PACG), 12 had nanophthalmic ACG, and 26 had ACG with retinal diseases. Most patients who underwent lens replacement (85) had PACG, 19 had nanophthalmos, 14 had retinitis pigmentosa, 9 had bestrophinopathy, and 3 had retinoschisis.

IOP and medication use decreased after each surgery in each subgroup, but filtering surgery did not achieve statistically significant reductions of IOP in the nanophthalmic group after 3 months. Filtering surgery prompted decreases in best-corrected visual acuity (BCVA) after surgery, according to the investigators. Lens replacement did not have a significant impact on BCVA.

Among eyes with retinal diseases, lens extraction (also called “clear lens extraction”) was associated with IOPs of 21 mm Hg or lower. The rate of qualified success was higher in the lens extraction group compared with the filtering surgery group.

Across subgroups, filtering surgery was associated with decreased visual acuity.

Severe complications occurred after both filtering surgery and lens replacement for angle closure glaucoma. Two multivariable logistic regression models indicated that malignant glaucoma, the most frequent severe complication, was about 4 times more common among patients with retinal diseases compared with those who did not have retinal diseases and also about 4 times more likely among patients who underwent filtering surgery. Among patients who underwent filtering surgery, comorbid retinal diseases were linked with risk of postoperative malignant glaucoma.

“On the whole, our findings show that the efficacy of clear lens extraction is comparable to that of filtering surgery in medically uncontrolled young ACG, but clear lens extraction is safer, especially for young ACG with retinal diseases,” the researchers report.

Study limitations include retrospective nature, which involved limited ability to control for differences among surgeons, and incomplete visual field data.