In this prospective study, entitled "The Long-Term Efficacy of Overminus Lens Therapy in Intermittent Exotropia",the investigators examined the long-term impact of overminus lenses on the management of intermittent exotropia (IXT), treatment effect after overminus treatment has been discontinued and also investigated if overminus lenses cause myopia in long-term.

Purpose: To evaluate the long-term impact of overminus lenses in intermittent exotropia (IXT), to determine if the treatment effect would persist after overminus minus lenses are discontinued and also to investigate if overminus lenses cause myopia.

Materials and Method: Sixty-five consecutive cases of IXT followed for at least 48 months were included. Patients with a history of previous surgery, ocular pathology, convergence insufficiency, severe myopia (>-5.0 D), severe hyperopia (>+5.0 D), moderate or severe amblyopia and poor compliance with spectacles were excluded. Data was collected including near stereoacuity, AC/A ratio, control of IXT measured with Newcastle Control Score (NCS) at baseline and in all follow-up visits. Baseline values without overminus threapy were compared with postintervention values at every visit.

Inclusion Criteria:

• patients diagnosed with IXT
• prescribed overminus lenses

Exclusion Criteria:

• a history of previous surgery, ocular pathology
• convergence insufficiency type IXT
• presence of any type of ocular deviation except IXT
• presence of severe myopia (greater than -5.0 D)
• presence of severe hyperopia (greater than +5.0 D)
• presence of moderate or severe amblyopia
• poor compliance with overminus spectacles
• follow up period of <48 months after intervention.

All consecutive pediatric patients diagnosed with IXT and prescribed overminus lenses