Minus Overcorrection: Conservative Treatment of Intermittent Exotropia in the Young Child-A Comparative Study

Helen Goodacre, DipAppSc (Cumb), DOBA

Minus overcorrection is examined in the treatment of children, under 6 years of age, with intermittent exotropia of the divergence excess type. Minus lenses stimulate accommodative convergence which provides a stimulus to the fusional skills required to control a divergent deviation, A group of 22 children given minus overcorrection is compared with a second group of 12 children with whom minus overcorrection was not successful and later required surgery. Average strength prescribed was – 2.50 D.S.

68% of Group 1 and 62% of the total (Group 1 and Group 2) we exophoric at all distances after 12 months with overcorrection. 27% of the total also had a reduction in deviation size of >15Δ at 6 metres. Group 1 had a significantly smaller near deviation and higher AC/A ratio than Group 2 (p=0.01). It is concluded that minus overcorrection can enhance control of divergence in young children and may avoid unnecessary surgery.