Korean J Ophthalmol.  2017 Jun;31(3):268-274. 10.3341/kjo.2015.0168.

The Effect of Preoperative Occlusion Therapy on Long-term Outcome after Surgery for Early-onset Exotropia

• Shin KH
• Kim IN
• Paik HJ

• KMID: 2379884
• DOI: http://doi.org/10.3341/kjo.2015.0168

Abstract

PURPOSE
To investigate the effect of preoperative part-time occlusion therapy on long-term surgical success in early-onset exotropia.
METHODS
The medical records of patients who underwent surgery for exotropia with onset before the first year of age and who were followed for ≥3 years were reviewed. Patients were divided into two groups according to the degree of compliance with part-time occlusion therapy: the good compliance group (>50% adherence rate) and the poor compliance group (≤50% adherence rate). Surgical success was defined as orthophoria to exodeviation less than 10 prism diopters both at distance and near. The level of postoperative stereopsis was compared between the two study groups among total enrolled patients and among those with constant exotropia.
RESULTS
Of the 51 patients, 26 were assigned to the good compliance group and the remaining 25 patients to the poor compliance group. The surgical success rate was significantly higher in the good compliance group than in the poor compliance group (80.8% vs. 52.0%, p = 0.040). Among 24 constant exotropia patients (12 patients for each group), the success rate was insignificantly higher in the good compliance group than in the poor compliance group (75.0% vs. 58.3%, p = 0.448). The good compliance group had a better level of stereopsis than the poor compliance group (p = 0.045 for all 44 patients, p = 0.020 for 19 patients with constant exotropia).
CONCLUSIONS
Preoperative part-time occlusion therapy was useful for improving the surgical outcome of early-onset exotropia and postoperative stereopsis.

Keyword

Compliance; Early-onset exotropia; Infantile exotropia; Part-time occlusion therapy; Stereopsis

MeSH Terms

Compliance
Depth Perception
Exotropia*
Humans
Medical Records

Figure

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  Fig. 1 The distribution of compliance rates with part-time occlusion therapy in 51 patients who underwent surgery for early-onset exotropia.

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  Fig. 2 The Kaplan-Meier estimates of surgical outcome in the two study groups according to the degree of compliance with part-time occlusion therapy: (A) success rate (p = 0.049), (B) recurrence rate among a total of 51 enrolled patients (p = 0.046).

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  Fig. 3 The level of stereopsis in the two study groups according to the degree of compliance with part-time occlusion therapy: (A) among a total of 44 enrolled patients (p = 0.045), (B) among 19 patients with early-onset constant exotropia (p = 0.020).

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