Journal List > J Korean Ophthalmol Soc > v.51(1) > 1008811

Kim, Park, and Yoo: The Effects of Occlusion Therapy in Patients With Anisometropic Amblyopia Aged 8 Years and Older

Abstract

Purpose

To compare the effects of full-time and part-time occlusion therapy in patients who had been diagnosed with anisometropic amblyopia after age eight and have begun treatment.

Methods

We included patients eight years old or older who had been diagnosed with anisometropic amblyopia. They were treated with full-time or part-time occlusion therapy and followed up for at least six months. Treatment was considered successful when visual acuity was increased by two lines or more.

Results

There were 26 total patients. There were 14 part-time and 12 full-time occlusion therapy patients in the respective groups. Visual acuity for the amblyopic eyes was significantly improved while the non-amblyopic eyes did not show any significant differences after the treatment. The changes in the visual acuity were significantly larger for the full-time treatment group compared to the part-time treatment group. The full-time occlusion group showed a significant difference in visual acuity of the amblyopic eyes after treatment. Lower visual acuity of an amblyopic eye at the first visit led to a greater improvement in visual acuity after the treatment.

Conclusions

With good compliance, occlusion therapy for anisometropic amblyopia can be successful even if it is initiated after eight years of age.

References

1. von Noorden GK, Campos EC. Binocular vision and ccular motility. 6th ed.Missouori: CV Mosby;2002. p. 246–97.
2. Scott WE. Full-time occlusion therapy for amblyopia. Am Orthopt J. 1980; 30:125–30.
crossref
3. Daw NW. Critical periods and amblyopia. Arch Ophthalmol. 1998; 116:502–5.
crossref
4. Hubel DH, Wiesel TN. The period of susceptibility to the aberrations effects of unilateral eye closure in kittens. J Physiol. 1970; 206:419–36.
5. Hussein MA, Coats DK, Muthialu A, et al. Risk factors for treatment failure of anisometropic amblyopia. J AAPOS. 2004; 8:429–34.
crossref
6. Flynn JT, Schiffman J, Feuer W, Corona A. The therapy of aberrations: an analysis of the results of amblyopia therapy utilizing the pooled data of published studies. Trans Am Ophthalmol Soc. 1998; 96:431–50.
7. Rustein RP, Fuhr PS. Efficacy and stability of amblyopia therapy. Optom Vis Sci. 1992; 69:747–54.
8. Ahn JK, Hwang JM. Efficacy of occlusion therapy in amblyopia patients older than 9 years of age. J Korean Ophthalmol Soc. 2002; 43:1724–9.
9. Moon CS, Jin YH. Timing of amlyopia therapy in pure aberrations amblyopia. J Korean Ophthalmol Soc. 1998; 39:185–92.
10. Levartovsky S, Oliver M, Gottesman N, Shimshoni M. Factors affecting long term results of successfully treated amblyopia: initial visulal acuity and type of amblyopia. Br J Ophthalmol. 1995; 79:225–8.
11. Oliver M, Neumann R, Chaimovitch Y, et al. Compliance and results of treatment for amblyopia in children more than 8 years old. Am J Ophthalmol. 1986; 102:340–5.
crossref
12. Epelbaum M, Milleret C, Buisseret P, Dufier JL. The sensitive period of strabismic amblyopia in humans. Ophthalmology. 1993; 100:323–7.
13. Simons K, Stein L, Sener EC, et al. Full-time atropine, intermittent atropine, and optical penalization and binocular outcome in aberrations of strabismic amblyopia. Ophthalmology. 1997; 104:2143–55.
14. Smith LK, Thompsin JR, Woodruff G, Hiscox F. Factors aberrations treatment compliance in amblyopia. J Pediatr Ophthalmol Strabismus. 1995; 32:98–101.
15. Ku HC, Lee SY, Lee YC. Clinical features and counterplans of monocular amblyopia failed to occlusion therapy. J Korean aberrations Soc. 2005; 46:1158–66.
16. Mintz-Hittner HA, Fernandez KM. Successful amblyopia therapy initiated after age 7 years: compliance cures. Arch Ophthalmol. 2000; 118:1535–41.
17. Cobb CJ, Russell K, Cox A, MacEwen CJ. Factors influencing visual outcome in anisometropic amblyopes. Br J Ophthalmol. 2002; 86:1278–81.
crossref
18. Park YK, Yoon KC, Park YG. Clinical approach for the aberrations of amblyopia in school children. J Korean Ophthalmol Soc. 2003; 44:2091–8.
19. Oh DE, Lim KH. Efficacy of occlusion therapy in Amblyopia: type, depth & timing of amblyopia. J Korean Ophthalmol Soc. 2003; 44:2850–6.
20. Rho SS, Yang HS, Chang YH, et al. The effect on outcome of amblyopia treatment in children with anisometropic amblyopia. J Korean Ophthalmol Soc. 2007; 48:535–40.
21. Kim YH, Choi MY. The prospective comparison of the efficacy of intermittent atropine penalization and part-time occlusion therapy. J Korean Ophthalmol Soc. 2008; 49:958–66.
crossref
22. The Pediatric Eye Disease Investigator Group. A randomized trial of atropine vs patching for treatment of moderate amblyopia in children. Arch Ophthalmol. 2002; 120:268–78.
23. The Pediatric Eye Disease Investigator Group. A comparison of atropine and patching treatments for moderate amblyopia by patient age, cause of amblyopia, depth of amblyopia, and other factors. Ophthalmology. 2003; 110:1632–8.
24. The Pediatric Eye Disease Investigator Group. Two-year follow-up of a 6-month randomized trial of atropine vs patching for treatment of moderate amblyopia in children. Arch Ophthalmol. 2005; 123:149–57.
25. Yu DK, Choi MY. The efficacy of intermittent atropine aberrations in amblyopic children who have failed patching therapy. J Korean Ophthalmol Soc. 2005; 46:1167–74.
26. Leiba H, Shimshoni M, Oliver M, et al. Long term follow-up of occlusion therapy in amblyopia. Ophthalmology. 2001; 108:1552–5.
27. Ohlsson J, Banumann M, Sjostrand J, Abrahamsson M. Long term visual outcome in amblyopic treatment. Br J Ophthalmol. 2002; 86:1148–51.
28. Ching FC, Parks MM, Friendly DS, et al. Practical management of amblyopia. J Pediatr Ophthalmol Strabismus. 1986; 23:12–6.
crossref
29. Levartovsky S, Gottesman N, Shimshoni M, Oliver M. Factors affecting long-term results successfully treated amblyopia: age at beginning of treatment and age at cessation of monitoring. J Pediatr Ophthalmol Strabismus. 1992; 29:219–23.
30. Bhola R, Keech RV, Kutscheke P, et al. Recurrence of amblyopia after occlusion therapy. Ophthalmology. 2006; 113:2097–100.
crossref

Table 1.
Clinical characteristics of 12 amblyopic patients treated by full-time occlusion
Age /Sex Initial visual acuity (logMAR)
Duration of treatment (months) Anisometropia (Diopter) Final visual acuity (logMAR)
OD OS OD OS
11/M 0 0.8 6 3.75 0 0.5
11/F 0 0.8 7 3.25 0.1 0.7
11/M 0.7 0 7 2 0.3 0.1
10/F 0 1 7 3 0 0.5
10/M 0 1 14 6 0 0.1
9/M 0.7 0 7.7 4.25 0.2 0
8/F 0.1 1 7.5 4 0.1 0.7
10/F 0 0.5 12.6 2.5 0 0.4
8/F 0.5 0.1 6.6 8 0.2 0.1
8/F 0.2 0 25.2 5.25 0.1 0
8/M 0 1 10 6.5 0 0.7
8/M 0.5 0.1 6.3 2 0.2 0.1
Table 2.
Clinical characteristics of 14 amblyopic patients treated by part-time occlusion
Age/Sex Initial visual acuity (logMAR)
Duration of treatment (months) Anisometropia (Diopter) Final visual acuity (logMAR)
OD OS OD OS
13/F 0 0.8 7.1 5 0 0.4
11/M 0.1 0.2 6 1.5 0.1 0.1
10/M 0.1 0.3 6.1 3 0 0.2
8/M 0 0.5 9 2.5 0 0.2
10/M 0.1 0.7 21.1 3 0.1 0.5
8/F 0 0.2 14 2 0 0.2
8/F 0.7 0 13 4.75 0 0
8/F 0 0.2 6.1 3.5 0 0.1
8/M 0.1 0.2 6.6 2.75 0.1 0.1
8/M 0 0.3 9.6 2.75 0 0.2
8/M 0.3 0 6.6 4.5 0.2 0
9/M 0.3 0 8 −5 0.2 0
9/M 1 0 6.5 3.5 1 0
8/M 0.3 0 7 5.25 0.3 0
Table 3.
Clinical results of total, part-time and full-time occlusion patients
Total (n=26) Full-time (n=12) Part-time (n=14) p-value*
Mean age (years) 9.15±1.41 9.33±1.30 9.0±1.52 0.557
Initial VA in amblyopic eye (LogMAR) 0.565±0.30 0.73±0.26 0.43±0.26 0.008
Initial VA in sound eye (LogMAR) 0.03±0.05 0.03±0.05 0.03±0.05 0.846
Anisometropia (Diopter) 3.83±1.57 4.21±1.89 3.50±1.21 0.259
Final VA in amblyopic eye (LogMAR) 0.32±0.24 0.39±0.23 0.26±0.27 0.259
Final VA in sound eye (LogMAR) 0.03±0.05 0.04±0.05 0.02±0.04 0.283
Duration of follow-up (Months) 10.05±4.96 10.6±5.70 9.57±4.40 0.605

* p-value=Mann-Whitney U test between full-time and part-time occlusion patients.

Table 4.
Clinical findings according to the degree and type of anisometropia, initial visual acuity in the amblyopic eye and age in the total, full-time and part-time occlusion patients
Total (No. of success) Full-time (No. of success) Part-time (No. of success)
Anisometropia (diopters) <2 1 (1) 0 1 (1)
2≤ and <4 14 (7) 6 (4) 8 (3)
4≤ and <6 8 (4) 3 (2) 5 (2)
≥6 3 (3) 3 (3) 0
Anisometropia (type) Hyperopia 19 (13) 10 (7) 9 (6)
Myopia 7 (2) 2 (2) 5 (0)
Initial visual acuity 0.2≤ and <0.4 10 (4) 1 (1) 9 (3)
in amblyopic eye 0.4≤ and <0.6 4 (3) 3 (2) 1 (1)
(logMAR) ≥0.6 12 (8) 8 (6) 4 (2)
Age (years) 8 ∼ 9 16 (9) 6 (5) 10 (4)
≥10 10 (6) 6 (4) 4 (2)
Table 5.
Changes of visual acuity in amblyopic eye and success rate of occlusion treatment in the total, full-time and part-time occlusion patients
Changes of visual acuity in amblyopic eye (logMAR) p-value* Success rate of occlusion(%) p-value
Total (n=26) 0.221±0.04 57.7
Full-time Occlusion (n=12) 0.342±0.223 0.014 75.0 0.02
Part-time Occlusion (n=14) 0.164±0.191 42.9

* p-value=Wilcoxon signed rank test

p-value=Fisher's exact test.

Table 6.
Correlations between each factors of intial age, anisometropia, initial visual acuity of amblyopic eye and changes of visual acuity of the amblyopic eye
Anisometropia (p-value) Age (p-value) Initial V/A in amblyopic eye (p-value)
Changes of visual acuity in amblyopic eye (logMAR) Total −0.229 (0.260) −0.2555 (0.269) −0.619 (0.001)
Full-time −0.108 (0.739) −0.215 (−0.501) −0.675 (0.016)
Part-time 0.019 (0.948) −0.189 (0.517) −0.267 (0.356)
Success rate of occlusion(%) Total −0.520 (0.618) −0.168 (0.880) −0.448 (0.668)
Full-time −0.834 (0.459) −0.487 (0.864) −0.285 (0.836)
Part-time −0.584 (0.588) 0 (1) −0.401 (0.740)
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