LENS EXCHANGE

Refractive lens exchange (RLE) in amblyopic eyes is safe and can improve corrected distance visual acuity (CDVA) in both hyperopes and myopes, reported Mark Wevill MD, at the XXIX Congress of the ESCRS. Dr Wevill, specialist eye surgeon, Ultralase Clinics, Birmingham, UK, and visiting lecturer, Aston University, Birmingham, UK, presented results from a retrospective analysis of visual outcomes after RLE in a series of 23 consecutive eyes for which no pathological cause was identified for the amblyopia. Cataract, keratoconus, macular pathology and optic neuropathy were all ruled out, and the amblyopia was either due to strabismus, anisometropia, or had an unexplained aetiology.

All eyes had preoperative logMAR CDVA ≤0.2 (~6/9) and were implanted with the same, single focus IOL (Tetraflex, Lenstec).

There were 12 patients in the series ranging in age from 18 to 64 years, and the 23 eyes included 16 hyperopes and seven myopes. Among the hyperopes, mean SE preoperatively was +4.23 ± 2.03 D and mean logMAR CDVA was 0.2 ± 0.08 (~6/9). At one month after surgery, mean SE was -0.57 ± 1.01 D and mean logMAR CDVA improved to 0.15 ± 0.13 D (6/7.5 to 6/9).

The myopes had a mean preoperative SE of -8.82 ±1.91 D and a mean CDVA of 0.32 ± 0.23 (~6/12). The refractive target was for myopia (monovision) in four of these eyes. One month mean SE was -1.21 ± 0.82 D. LogMAR CDVA improved to a mean of 0.15 ± 0.11.

No eyes in the series lost two or more lines of vision. Among the hyperopes, three eyes lost one line and five eyes stayed the same, while eight eyes gained CDVA, including three eyes that gained two lines and five eyes that gained one line.

In the myopic group, only one eye had a one-line loss of CDVA and one eye remained the same. Four eyes gained two lines and one eye gained one line.

“CDVA improved greatly after RLE in the myopic eyes. They may have some benefit from image magnification, but our sample size is too small to see if the amblyopia was improved or if the outcomes are due to a refractive effect,†said Dr Wevill.

“However, there was also improvement in the hyperopes even though image size is reduced, and seeing that these eyes benefit from the procedure is a good sign,†said Dr Wevill.

He added a few other caveats for interpreting the visual acuity results.

“When assessing visual acuity at one month after surgery, we also have to consider there may be some early capsular changes, especially in younger patients, and cystoid macular oedema still present, especially in older patients. These factors may be limiting CDVA and our patients’ outcomes should tend to improve with time.â€