Over-correction avoided by administering correct dosage

Over-correction in children with intermittent exotropia can be avoided by using the correct surgical dosage.

A team led by Dr Deborah Buck, Institute of Neuroscience, Medical School, Newcastle University, Newcastle upon Tyne, UK, included 87 children with intermittent exotropia who underwent surgery in 18 centres across the UK.

Primary outcome measures included motor/sensory outcome and the secondary outcome measure was satisfactory control assessed by the Newcastle Control Score (NCS).

Of the 87 children studied, 72 were available for review data. Preoperative and surgical characterisitics had no effect on the primary outcome and satisfactory control was achieved in 65% of patients, whilst 20% still had intermittent extropia.

It was discovered that 35%, 28% and 37% of patients had excellent, fair and poor primary outcomes, respectively. Persistent over-correction was found in 15% of the patients and there was no recorded relationship between over-correction and preoperative characteristics or surgical dose/type.

At near and distance visions the median angle improved by 12 prism dioptres (PD) and 19 PD, respectively. The median NCS improved by five and the 40% who were initiallt over-corrected remained over-corrected by the last postoperative assessment.

The abstract was published in the latest issue of the British Journal of Ophthalmology.