Paediatric LASIK

Long-term data suggest that LASIK may be employed safely and successfully in children with anisometropia and high myopia to treat or prevent amblyopia that is refractory to conventional treatments, according to a study presented here. “LASIK in children is very rare and still controversial, but it may be indicated in exceptional circumstances such as high myopia or high anisometropia where the patients are poorly compliant or have failed to respond to conventional amblyopia treatment,†Claire Hartnett MD told delegates attending the XXIX Congress of the ESCRS.

Dr Hartnett’s case series included seven eyes of six children who underwent LASIK between 2000 and 2005 at the Children’s University Hospital, Dublin, Ireland. The patients’ ages ranged from 2.5 to 8.5 years with a mean of four years.

Five of the children presented with highly myopic anisometropic eyes and one child had bilateral high myopia. The mean spherical equivalent was -9 D and all patients had failed conventional amblyopia/anisometropia treatment. All LASIK surgeries were performed under general anaesthesia with a flap size between 8.5mm to 9.5mm and an optical zone of 5.5mm to 6.0mm. In all patients the aim was to achieve a symmetrical refraction and to reduce the anisometropia, said Dr Hartnett.

Myopia reduction

The results showed no intra- or postoperative complications with a mean follow-up of 9.5 years. Visual acuity improved in six out of seven eyes with a mean improvement of 2.5 Snellen lines. One patient had no change in visual acuity and remained amblyopic. All eyes achieved a reduction in myopia and an improvement in symmetrical refraction with a reduction in anisometropia. The mean spherical equivalent went from -9.6 preoperatively to -3.0 D postoperatively after two years and -4.3 D at 9.5 years.

In terms of long-term outcomes, Dr Hartnett noted that myopic regression had not occurred at two years postoperatively but was found in five out of seven eyes at the end of the follow-up period. The mean myopic regression was -2.4 D in the treated eyes and -3.7 D in the fellow non-treated eyes.

There was no evidence of corneal ectasia or haze, epithelial ingrowth, flap complications or complaints of glare. The pachymetry results were satisfactory overall with a mean central corneal thickness of 472 microns.

Summing up, Dr Hartnett said that the study was limited by the fact that it was a small case series, but said that to her knowledge this was the first report of long-term follow-up of LASIK in young children.

LASIK may also be successfully employed as an alternative treatment for non-compliant paediatric patients with esotropia, according to a separate study presented by Ahmed M Saeed MD, Benha University, Egypt.

Dr Saeed noted that accommodative esotropia is the most common type of strabismus with a very favourable prognosis if the appropriate treatment is initiated promptly. Traditional methods of treatment included spectacle or contact lens correction for the cycloplegic hyperopic refractive error.

“We found a considerable proportion of the spectacle-dependent children did not wear their glasses or did not return for follow-up visits. This non-compliance leads to loss of stereopsis and development of ammetropic and strabismic amblyopia which is difficult to correct later on,†he said.

Dr Saeed’s study included 20 eyes of 10 consecutive paediatric patients with accommodative esotropia. All patients were non-compliant with spectacles and had stable refraction for at least 12 months prior to the LASIK procedure. The mean patient age was seven years. All patients underwent bilateral LASIK under general anaesthesia using standard hyperopic nomograms on the Allegretto Wave (Alcon) excimer laser platform to fully correct their cycloplegic hyperopic refractive error.

All eyes were within 0.5 D to +1.5 D of emmetropia at the final evaluation, with a statistically significant improvement of the refractive error. Dr Saeed noted that all patients achieved orthophoria and no significant intraoperative or postoperative complications were recorded.

“While there are some obvious limitations to the study in terms of the small number of patients, short follow-up time and lack of a comparison group, LASIK does seem to be an effective and relatively safe method to treat accommodative esotropia in young children, although the role of careful patient selection must be emphasised,†he concluded.

contacts Claire Hartnett – claire.hartnett@cuh.ie    Ahmed M Saeed – a_saeed775@yahoo.com