Korean J Ophthalmol.  2015 Jun;29(3):173-177. 10.3341/kjo.2015.29.3.173.

Relationship between Control Grade, Stereoacuity and Surgical Success in Basic Intermittent Exotropia

• Kang KT
• Lee SY

• KMID: 2363755
• DOI: http://doi.org/10.3341/kjo.2015.29.3.173

Abstract

PURPOSE
This study was conducted to identify the relationship between control grade, stereoacuity and surgical success in basic intermittent exotropia.
METHODS
This retrospective study involved 44 basic intermittent exotropia patients who underwent strabismus surgery and completed at least 6 months of follow-up. The 44 patients were divided into three subgroups according to their control grade: group 1 (good control group, n = 12), group 2 (fair control group, n = 18), and group 3 (poor control group, n = 14). Evaluation was done to identify the relationships between near and distance stereoacuity and control grade, and between surgical success and control grade. Surgical success was defined as ocular alignment between 5 prism diopters esodeviation and 10 prism diopters exodeviation in the primary position at the final visit.
RESULTS
Mean near stereoacuity measured by the graded circle test was 57.50 seconds of arc (seconds) in group 1, 77.77 seconds in group 2, and 131.43 seconds in group 3 (p < 0.01). Mean distance steroacuity measured by Mentor B-VAT II BVS contour circle was 108.33 seconds in group 1, 148.33 seconds in group 2, and 262.82 seconds in group 3 (p < 0.01). Ten patients (83.33%) in group 1, 12 (66.67%) in group 2, and 9 (64.29%) in group 3 obtained surgical success (p = 0.28).
CONCLUSIONS
In basic intermittent exotropia, better control grade was significantly accompanied by better stereoacuity. Better control grade was accompanied by higher surgical success rate but with no statistical significance.

Keyword

Exotropia; Prevention & control; Stereoacuity; Strabismus

MeSH Terms

Child
Child, Preschool
Exotropia/physiopathology/*surgery
Female
Humans
Male
Ophthalmologic Surgical Procedures
Retrospective Studies
Treatment Outcome
*Visual Acuity

Reference

1. Jenkins R. Demographics: geographic variations in the prevalence and management of exotropia. Am Orthopt J. 1992; 42:82–87.

2. Ing MR, Pang SW. The racial distribution of strabismus. In : Reike RD, editor. Strabismus III. New York: Grune & Stratton;1978. p. 107–109.

3. Rosenbaum AL, Stathacopoulos RA. Subjective and objective criteria for recommending surgery in intermittent exotropia. Am Orthopt J. 1992; 42:46–51.

4. O'Neal TD, Rosenbaum AL, Stathacopoulos RA. Distance stereo acuity improvement in intermittent exotropic patients following strabismus surgery. J Pediatr Ophthalmol Strabismus. 1995; 32:353–357.

5. Lee HS, Lew H, Choi HJ. Clinical significance of refixation time in intermittent exotropia. J Korean Ophthalmol Soc. 2003; 44:1567–1571.

6. Yang HS, Kim YH, Lee SY, Kim SJ. The influence of fusional vergence on the postoperative ocular alignment in intermittent exotropia. J Korean Ophthalmol Soc. 2000; 41:1597–1603.

7. Von Noorden GK. Binocular vision and ocular motility: theory and management of strabismus. 6th ed. St. Louis: Mosby;2002. p. 356–376.

8. Jampolsky A. Characteristics of suppression in strabismus. AMA Arch Ophthalmol. 1955; 54:683–696.

9. Rosenbaum AL, Santiago A. Intermittent exotropia: clinical strabismus management. Philadelphia: WB Saunders;1999. p. 156–168.

10. Park BC, Lee JY. Control grade of intermittent exotropia and related factors. J Korean Ophthalmol Soc. 2006; 47:1781–1790.

11. Han JH, Kim DS, Shin JC. Amblyopia and sensory fusional anomaly in intermittent exotropia. J Korean Ophthalmol Soc. 2000; 41:495–499.

12. Stathacopoulos RA, Rosenbaum AL, Zanoni D, et al. Distance stereoacuity: assessing control in intermittent exotropia. Ophthalmology. 1993; 100:495–500.

13. Lee SY. Comparison of distance and near stereoacuity in normal and intermittent exotropic children. J Korean Ophthalmol Soc. 2001; 42:624–629.

14. Scott AB, Mash AJ, Jampolsky A. Quantitative guidelines for exotropia surgery. Invest Ophthalmol. 1975; 14:428–436.

15. Kim HW, Yang JW, Won IK. Clinical study for risk factors of recurrence in intermittent exotropia. J Korean Ophthalmol Soc. 2000; 41:1417–1424.

16. Kushner BJ, Fisher MR, Lucchese NJ, Morton GV. Factors influencing response to strabismus surgery. Arch Ophthalmol. 1993; 111:75–79.