Journal List > J Korean Ophthalmol Soc > v.49(2) > 1008189

Kim, Choi, and Kim: Clinical Analysis of Successfully Treated Amblyopia with Anisometropia, Strabismis, and Combined Cause

Abstract

Purpose

To evaluate the duration of therapy in amblyopic children with anisometropia and/or strabismus who had been successfully treated with a best corrected visual acuity (BCVA) of 1.0.

Methods

The duration of amblyopic treatment was compared according to the cause of amblyopia (anisometropia, strabismus, combined), the initial BCVA of amblyopic eye, the age at treatment, and the prediction of a further duration of treatment needed.

Results

The mean age of amblyopic treatment in 66 amblyopic children with anisometropia and strabismus was 5.4 years and the mean duration of treatment to gain BCVA of 1.0 was 15.9 months. The duration of treatment was longer in children with initially poorer BCVA and in younger aged children than in older aged children at diagnosis. However, there was no statistical significance according to the cause of amblyopia. In occlusion therapy, the patching time from the initial BCVA to 1.0 was not statistically different from the patching time from the midpoint VA (between the initial visual acuity and 1.0) to 1.0.

Conclusions

The duration of treatment to gain a VA of 1.0 was dependent on the degree of the initial BCVA in the amblyopic eye and the age at treatment. In occlusion therapy, the duration of further treatment to gain a BCVA of 1.0 was necessary as much as the duration to gain a midpoint VA from the initial BCVA. J Korean Ophthalmol Soc 49(2):303-308, 2008

References

1. von Noorden GK. Binocular Vision and Ocular Motility. 6th ed.St. Louis: C.V. Mosby;2002. p. 246.
2. Tommila V, Tarkkanen A. Incidence of loss of vision in the healthy eye in amblyopia. Br J Ophthalmol. 1981; 65:575–7.
crossref
3. Woodruff G, Hiscox F, Thompson JR, Smith LK. Factors affecting the outcome of children treated for amblyopia. Eye. 1994; 8:627–31.
crossref
4. Oh DE, Lim KH. Efficacy of occlusion therapy in amblyopia: type, depth and timing of amblyopia. J Korean Ophthalmol Soc. 2003; 44:2850–6.
5. Lithander J, Sjöstrand J. Anisometropic and strabismic amblyopia in the age group 2 years and above: a prospective study of the results of treatment. Br J Ophthalmol. 1991; 75:111–6.
crossref
6. 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.
7. Beardsell R, Clarke S, Hill M. Outcome of occlusion treatment for amblyopia. J Pediatr Ophthalmol Strabismus. 1999; 36:19–24.
crossref
8. Romano PE, Romano JA, Puklin JE. Stereoacuity development in children with normal binocular single vision. Am J Ophthalmol. 1975; 79:966–71.
crossref
9. Flynn JT, Woodruff G, Thompson JR, et al. The therapy of amblyopia: an analysis comparing the results of amblyopia therapy utilizing two pooled data sets. Trans Am Ophthalmol Soc. 1999; 97:373–90.
10. Hiscox F, Strong N, Thompson JR, et al. Occlusion for amblyopia: a comprehensive survey of outcome. Eye. 1992; 6:300–4.
crossref
11. Holmes JM, Kraker RT, Beck RW, et al. Pediatric Eye Disease Investigator Group. A randomized trial of prescribed patching regimens for treatment of severe amblyopia in children. Ophthalmology. 2003; 110:2075–87.
12. Mintz-Hittner HA, Fernandez KM. Successful amblyopia therapy initiated after age 7 years: compliance cures. Arch Ophthalmol. 2000; 118:1535–41.
13. Kim IS, Cho YA. Therapy of strabismic amblyopia less than 0.1 vision. J Korean Ophthalmol Soc. 1995; 36:338–43.
14. Levy NS, Glick EB. Stereoscopic perception and Snellen visual acuity. Am J Ophthalmol. 1974; 78:722–4.
crossref
15. Burian HM. Stereopsis. Doc Ophthalmol. 1951; 5-6:169–83.
crossref
16. Lee SY, Isenberg SJ. The relationship between stereopsis and visual acuity after occlusion therapy for amblyopia. Ophthalmology. 2003; 110:2088–92.
crossref
17. Sen DK. Results of treatment of anisohypermetropic amblyopia without strabismus. Br J Ophthalmol. 1982; 66:680–4.
crossref
18. Weakley DR Jr. The association between nonstrabismic anisometropia, amblyopia, and subnormal binocularity. Ophthalmology. 2001; 108:163–71.
crossref
19. Chung JK, Choi KS, Park SH. Qualitative assessment of binocular and monocular visual function in successfully treated amblyopes. J Korean Ophthalmol Soc. 2006; 47:947–53.

Table 1.
Binocularity index
0 Complete suppression
1 Only fusion W4D* at near
2 Fusion of the Titmus stereo fly
3 100∼400 arc seconds on Titmus stereo test
4 ≤ 80 arc seconds on Titmus stereo test

* W4D=Worth 4-dot test.

Table 2.
Characteristics according to age at diagnosis of amblyopia
  Age〈5 5≤ Age〈7 Age ≥7 p-value *
Initial VA (LogMAR)        
 Amblyopic eye 0.76±0.53 0.44±0.31 0.34±0.17 0.002
 Sound eye 0.20±0.13 0.07±0.11 −0.02±0.10 0.000
 Interocular difference 0.43±0.32 0.44±0.38 0.39±0.37 0.898
Duration of therapy (months) 23.04±14.75 12.00±9.60 10.61±6.83 0.001

* Statistical significance was test by analysis of variance (ANOVA).

p<0.05, group under 5 years was significantly different from the other groups with Duncan's multiple range test.

Table 3.
Baseline characteristics according to the causes of amblyopia
  AA* SA MA p-value
Initial age (years) 6.1±1.7 4.9±1.7 4.4±1.4 0.003
Initial VA§ (LogMAR)        
 Amblyopic eye 0.53±0.37 0.54±0.49 0.61±0.45 0.829
 Sound eye 0.07±0.13 0.14±0.17 0.13±0.10 0.189
 Interocular difference 0.46±0.34 0.38±0.38 0.48±0.41 0.681
Duration of therapy (months) 13.47±12.42 16.25±9.76 21.46±15.69 0.151

* AA=anisometropic amblyopia

SA=strabismic amblyopia

MA=mixed amblyopia

§ VA=visual acuity

Statistical significance was test by analysis of variance (ANOVA)

p<0.05, anisometropic amblyopia group was significantly different from the other groups with Duncan's multiple range test.

Table 4.
Characteristics according to the degree of amblyopia
  Degree of amblyopia
p-value§
Mild* Moderate Severe
Initial age (years) 6.0±1.5 5.7±1.7 4.5±1.9 0.019
Binocularity index (scales) 2.9±1.3 2.8±1.2 2.7±1.5 0.883
Duration of therapy (months) 8.9±7.5 12.9±8.1 26.5±15.4 0.000

* Mild=≥0.6

Severe=≤0.2 (visual acuity); (ANOVA); test.

Moderate=0.3≤ ≤0.5

§ Statistical significance was tested by analysis of variance (ANOVA)

p<0.05, severe amblyopia group was significantly different from the other groups with Duncan's multiple range

Table 5.
Binocularity index after successful treatment
Binocularity index (scales) AA (n) SA
MA (n) N (%)
XT (n) ET (n)
0 1 0 5 2 8 (12.5)
1 1 0 0 1 2 (3.1)
2 3 0 1 1 5 (7.8)
3 11 4 9 5 29 (45.3)
4 15 1 0 4 20 (31.3)
Total 31 5 15 13 64 (100)

AA=anisometropic amblyopia; SA=strabismic amblyopia; XT=exotropia; ET=esotropia; MA=mixed amblyopia.

TOOLS
Similar articles