J Korean Ophthalmol Soc.  2014 Apr;55(4):585-589.

The Effects of Part-Time Occlusion Therapy Shortened to One or Two Hours in Intermittent Exotropia

• Lee KH
• Suh YW
• Cho YA

Abstract

PURPOSE
To evaluate the compliance level of therapy and the change in exo-angle after 1 or 2 hours of part-time occlusion therapy in intermittent exotropia.
METHODS
This retrospective study included 97 patients with intermittent exotropia who were followed-up for more than 6 months after their initial visit. We evaluated the exo-angle and prescribed either 1 hour or 2 hours of part-time occlusion therapy for the fixating eye. After 6 months, the exo-angle was reevaluated and compliance was examined. Patients were divided into 2 groups according to the occlusion therapy time: the 1-hour patching group (33 patients) and the 2-hour patching group (64 patients). Compliance and deviation angle were retrospectively reviewed and compared between the 2 groups. We evaluated the exo-angle of patients with compliance over 50% (1-hour patching group (31 patients), 2-hour patching group (51 patients)).
RESULTS
The mean exo-angles on the first visit were 22.61 +/- 5.78 PD (prism diopters) at distance and 22.88 +/- 8.11 PD at close-range in the 1-hour patching group, and 26.17 +/- 4.55 PD at distance and 25.27 +/- 8.54 PD at close-range in the 2-hour patching group. The proportion of patients with compliance over 50% was higher in the 1-hour patching group (93.94%) than in the 2-hour patching group (79.69%, p = 0.013). There were significant decreases in distant and close- range deviation angles after part-time occlusion in patients with compliance over 50% in both groups (1-hour patching group distant p = 0.042, close-range p = 0.002; 2-hour patching group distant p < 0.001, close-range p < 0.001). The magnitude of deviation angle decrease was not statistically significant between the 2 groups (ANCOVA; distant p = 0.461, near p = 0.761).
CONCLUSIONS
One or 2 hours of part-time occlusion therapy in intermittent exotropia provided beneficial effects, including decreasing the deviation angle. The magnitude of deviation angle decrease, however, was not different between the 2 times of therapy. Compliance was higher in the 1-hour part-time occlusion therapy group. Therefore, 1-hour part-time occlusion therapy could be effective in patients with poor cooperation.

Keyword

Compliance; Intermittent exotropia; Part-time occlusion therapy

MeSH Terms

Compliance
Exotropia*
Humans
Retrospective Studies

Reference

References

1. Rah SH, Jun HS, Kim SH. An epidemiologic survey of strabismus among school - children in Korea. J Korean Ophthalmol Soc. 1997; 38:2195–9.

2. Wright KW, Spiegel PH. Exotropia. Pediatric Ophthalmology and Strabismus. 2nd ed.New York: Springer;2003. chap. 14.

3. Yoon KC, Mun GH, Kim SD, et al. Prevalence of eye diseases in South Korea: data from the Korea National Health and Nutrition Examination Survey 2008-2009. Korean J Ophthalmol. 2011; 25:421–33.

4. von Noorden G. Principles of Nonsurgical Treatment. 5th ed.St. Louis: Mosby-Year Book;1996. p. 503.

5. Chutter CP. Occlusion treatment of intermittent divergent strabismus. Am Orthopt J. 1977; 27:80–4.

6. Flynn JT, McKenney S, Rosenhouse M. A method of feating intermittent divergence strabismus (author's transl). Klin Monbl Augenheilkd. 1975; 167:185–90.

7. Freeman RS, Isenberg SJ. The use of part-time occlusion for early onset unilateral exotropia. J Pediatr Ophthalmol Strabismus. 1989; 26:94–6.

8. Jin YH, Son JH. The effect of occlusion in intermittent exotropia. J Korean Ophthalmol Soc. 1991; 32:307–11.

9. Kim SH, Cho YA. Can we effectively delay surgery for intermittent exotropia in children less than 4 years of age? J Korean Ophthalmol Soc. 1996; 37:1382–8.

10. Park JY, Sohn HY, Cho YA. Is the nonsurgical treatment effective on intermittent exotropia in children of school-age? J Korean Ophthalmol Soc. 1995; 36:1561–7.

11. Kim SK, Yi ST, Kim SH, Cho YA. The long-term effect of part-time occlusion therapy according to compliance in recurrent intermittent exotropia. J Korean Ophthalmol Soc. 2009; 50:135–8.

12. Gnanaraj L, Richardson SR. Interventions for intermittent distance exotropia: review. Eye (Lond). 2005; 19:617–21.

13. Richard JM, Parks MM. Intermittent exotropia. Surgical results in different age groups. Ophthalmology. 1983; 90:1172–7.

14. Edelman PM, Brown MH, Murphree AL, Wright KW. Consecutive esodeviation then what? Am Orthopt J. 1988; 38:111–6.

15. Vishnoi SK, Singh V, Mehra MK. Role of occlusion in treatment of intermittent exotropia. Indian J Ophthalmol. 1987; 35:207–10.

16. Suh YW, Kim SH, Lee JY, Cho YA. Conversion of intermittent exotropia types subsequent to part-time occlusion therapy and its sustainability. Graefes Arch Clin Exp Ophthalmol. 2006; 244:705–8.