Lens extraction holds promise, remains controversial, in highly myopic children

KEYSTONE, Colo. — Refractive lensectomy can be an effective option for a select group of children with high anisometropic myopia who are noncompliant with contact lens or spectacle use, according to a surgeon.

Asim Ali, MD, presented the results of a small retrospective study here at the American Association for Pediatric Ophthalmology and Strabismus meeting.

Dr. Ali and colleagues looked at seven patients with anisometric-myopic amblyopia with a mean age of 9 years at the time of surgery. Those included had myopia of at least –12 D in addition to spectacle or contact lens intolerance. These patients also were absent any ocular disorders that would preclude intraocular surgery, such as glaucoma, uveitis or endothelial cell dysfunction. The ability to follow up with these patients for postoperative care was also important, Dr. Ali said.

Patients either underwent lensectomy alone, combined lensectomy/vitrectomy, or lensectomy/vitrectomy with IOL implantation, Dr. Ali said. Five patients were left aphakic and two were implanted with a phakic IOL.

There were two males and five females, with a mean preoperative error of –16.7 D (range of –12 D to –24.5 D) in the operated eye.

Five of the seven patients had a preoperative visual acuity of worse than 20/800, Dr. Ali said. The axial length averaged 4.4 mm longer in the operated eye than the fellow eye, he noted. All patients had strabismus, and most were exotropic.

The mean visual change was 17.3 D, Dr. Ali noted. Six of the seven eyes were corrected to within 3 D of the goal refraction, and the seventh eye was within 4 D of the goal.

Two patients had to undergo Nd:YAG laser capsulotomy after surgery due to complications, including one patient who had postoperative hyphema in an eye that had been previously treated for stage 4a retinopathy of prematurity.

Dr. Ali said he and colleagues concluded that the procedure was highly effective in terms of correcting ametropia, and did not cause any sight threatening complications in the study eyes. He cautioned that the procedure should be considered for a select group of patients only and that the family must understand the risks.

Alternatives to the approach, he said, include excimer laser procedures or phakic IOLs, which are also limited by the degree of myopia that can be treated, corneal thickness, or the depth of the anterior chamber.

In a follow up discussion to Dr. Ali’s presentation, Arlene V. Drack, MD, stressed the need to approach these results with caution. She said it is important to keep in mind the long-term risk of retinal detachment in highly myopic eyes, and posed the question of whether this risk is lessened by the use of phakic IOLs, rather than lens extraction.

“The big question is: does clear lens extraction benefit the patient?” Dr. Drack said. “The authors said it improved visual function, but there were no data presented to support what the functional improvement was.”

She called for future studies of this nature to include quality of life measures and better visual function data. Furthermore, she pointed out that one of the seven patients was functionally monocular, a fact not reported by Dr. Ali during the presentation and one that is contrary to the study’s title: unilateral lens extraction for high anisometropic myopia.

She said the paper is important in that “the authors extended our knowledge of refractive surgery in children,” but called for more data on visual function in the patients, as well as prospective data and quality of life measures in future studies.