Change in infantile exotropia
Reviewed by Fiona Rowe

This study investigated the clinical course of patients with infantile exotropia who initially presented with a small exo deviation of 10-18 prism dioptres. Eighty-six patients were reviewed: 35 with follow-up of >2 years without surgery and 51 with surgery. The mean first distance angle was -15.4 ±2.3PD. Non-surgical treatment included part-time occlusion, glasses and alternate day occlusion. Over follow-up the mean angle increased to -18 ±5.6PD. Tendency for increased exo deviation was more prominent than that of reducing exo deviation. Impaired initial stereo acuity may be a potential predisposing factor for exo progression. Those with constant versus intermittent distance deviation were more likely to progress to surgery. Nearly half of the children increased to >20PD. 

The clinical course of infantile exotropia with small initial deviation.
Lee BJ, Kim S-J, Yu YS.
JOURNAL PEDIATRIC OPHTHALMIC STRABISMUS
2015;52:206-12.