PDF
ePub
Citation
Print
Abstract
Purpose
To investigate the relationship between myopic progression and exodrift after surgery in patients with intermittent exotropia (X[T]).
Methods
Eighty-five patients who underwent bilateral lateral rectus recession for X(T) and had a follow-up of more than 1 year were recruited for the present study. Progression of myopia was determined by measuring the difference in spherical equivalent of both eyes between the initial and final refraction divided by the total follow-up time per patient. Postoperative exodrift was calculated by subtracting the deviation at postoperative 6 weeks from the deviation at the last follow-up, and the deviation at postoperative day 1 from the deviation at postoperative 6 weeks. Linear regression was conducted to determine the relationship between postoperative exodrift and myopic progression. The risk factors for recurrence, defined as exodeviation of 10 prism diopters or more at the final examination, were also analyzed.
Results
Sixty-eight (80.0%) subjects showed myopic progression of -0.50 diopters or more, and 47 (55.3%) had recurrence of exotropia during the mean follow-up period of 37.9 months. Patients with myopic progression showed more exotropic drift after postoperative 6 weeks than the patients without myopic progression (p < 0.01). Immediate postoperative overcorrection, oblique dysfunction, and a short follow-up period were associated with a low recurrence, whereas preoperative angle of exodeviation, sensory status, and age at the time of surgery were not.
Conclusions
In patients who underwent bilateral lateral rectus recession for X(T), a greater myopic progression was related with greater postoperative exodrift. As the development of myopia was observed to be axial in nature, the results from the present study raises the possibility that ocular elongation may reduce the effect of recession.
Figures and Tables
Figure 1
Correlation between late exodrift (EOMfinal - EOM6weeks) and myopic progression. (A) Late exodrift at far = 5.775 - 1.237 × Myopic progression (p=0.034, linear regression). (B) Late exodrift at near = 5.243 - 2.949 × Myopic progression (p = 0.001, linear regression). PD = prism diopters; D = diopters.
Figure 2
Schematic explanation of correlation between myopic progression and postoperative exodrift. As the progression of myopia is axial in nature, these results raise the possibility that ocular elongation may reduce the effect of recession.
Table 1
Comparison of preoperative clinical characteristics between success group and recurred group
Values are presented as mean ± SD or number.
PD = prism diopters; D = diopters.
*Success group is defined as <10 PD exotropia at last follow-up; †Recurred group is defined as ≥10 PD exotropia at last follow-up; ‡Refractive error represents as spherical equivalent; §Fusion at far and near: suppression at far or near: suppression at far and near: diplopia; ΠChi-square test; #Independent t-test.
Table 2
Comparison of clinical findings at final follow-up between success group and recurred group
Values are presented as mean ± SD.
Exodrift is defined as difference in exodeviation from at final follow-up to at postoperative day 1.
PD = prism diopters; D = diopters.
*Success group is defined as <10 PD exotropia at final follow-up; †Recurred group is defined as ≥10 PD exotropia at final follow-up; ‡Independent t-test.
Table 3
Comparison of exodrift between myopic progression group and non-myopic progression group
Values are presented as mean ± SD.
PD = prism diopters.
*Non-myopic progression group is defined as a case of myopic progression less than -0.50 diopters; †Myopic progression group is defined as a case of myopic progression of -0.50 diopters or more; ‡Independent t-test; §Early exodrift is defined as difference in exodeviation from at postoperative 6 weeks to at postoperative day 1; ΠLate exodrift is defined as difference in exodeviation from at final follow-up to at postoperative 6 weeks; #Total exodrift is defined as difference in exodeviation from at final follow-up to at postoperative day 1.
References
1. Kim JW, Lee JH, Rah SH. Postoperative exotropic drift: comparison of surgical methods combined with lateral rectus muscle recession in exotropia. J Korean Ophthalmol Soc. 2011. 52:1326–1330.
2. Hahm KH, Shin MC, Sohn MA. The change in deviation angle with time course after surgical correction of intermittent exotropia. J Korean Ophthalmol Soc. 2002. 43:2214–2219.
3. Hatsukawa Y. [Short-term and long-term prognosis of recession-resection surgery for exotropia]. Nihon Ganka Gakkai Zasshi. 1992. 96:1466–1476.
4. Maruo T, Kubota N, Sakaue T, Usui C. Intermittent exotropia surgery in children: long term outcome regarding changes in binocular alignment. A study of 666 cases. Binocul Vis Strabismus Q. 2001. 16:265–270.
5. Raab EL, Parks MM. Recession of the lateral recti. Early and late postoperative alignments. Arch Ophthalmol. 1969. 82:203–208.
6. Park YH, Kim MM. Surgical results of intermittent exotropia. J Korean Ophthalmol Soc. 1989. 30:969–974.
7. Chia A, Seenyen L, Long QB. Surgical experiences with two-muscle surgery for the treatment of intermittent exotropia. J AAPOS. 2006. 10:206–211.
8. Jeoung JW, Lee MJ, Hwang JM. Bilateral lateral rectus recession versus unilateral recess-resect procedure for exotropia with a dominant eye. Am J Ophthalmol. 2006. 141:683–688.
9. Ekdawi NS, Nusz KJ, Diehl NN, Mohney BG. The development of myopia among children with intermittent exotropia. Am J Ophthalmol. 2010. 149:503–507.
10. Choi DG, Kim PS. The surgical outcome of intermittent exotropia and the prognostic factors. J Korean Ophthalmol Soc. 1998. 39:1255–1263.
11. Richard JM, Parks MM. Intermittent exotropia. Surgical results in different age groups. Ophthalmology. 1983. 90:1172–1177.
12. Stoller SH, Simon JW, Lininger LL. Bilateral lateral rectus recession for exotropia: a survival analysis. J Pediatr Ophthalmol Strabismus. 1994. 31:89–92.
13. Lee JY, Choi DG. The clinical analysis of recurrence after surgical correction of intermittent exotropia. J Korean Ophthalmol Soc. 2002. 43:2220–2226.
14. Isenberg SJ, Abdarbashi P. Drift of ocular alignment following strabismus surgery. Part 2: using adjustable sutures. Br J Ophthalmol. 2009. 93:443–447.
15. Funata M, Tokoro T. Scleral change in experimentally myopic monkeys. Graefes Arch Clin Exp Ophthalmol. 1990. 228:174–179.
16. Steinert RF. Expert consult. Cataract Surgery. 2009. 3rd ed. Philadelphia: Saunders;33–35.
17. Donders FC. An Essay on the Nature and the Consequences of Anomalies of Refraction. 1899. v. 1:1st ed. Philadelphia: P Blakiston's Son & Co;59.
18. Von Noorden GK, Campos EC. Binocular Vision and Ocular Motility: Theory and Management of Strabismus. 2002. 6th ed. St Louis: Mosby;86–98.
19. Walsh LA, Laroche GR, Tremblay F. The use of binocular visual acuity in the assessment of intermittent exotropia. J AAPOS. 2000. 4:154–157.
XML Download