J Korean Ophthalmol Soc.  2013 Jul;54(7):1097-1103. 10.3341/jkos.2013.54.7.1097.

The Surgical Outcome of Intermittent Exotropia with Good Binocular Function

• Kim KT
• Choi DK
• Choi MY

• KMID: 2217422
• DOI: http://doi.org/10.3341/jkos.2013.54.7.1097

Abstract

PURPOSE
We investigated the success rate of surgery and binocular function after surgery in intermittent exotropia with good preoperative binocular function.
METHODS
Thirty-eight intermittent exotropia patients who had good stereopsis of 40 seconds according to the Titmus test, showed fusion by Worth-4-dot test preoperatively, and had at least 1 year of postoperative follow-up were included in the present study. The age at operation, angle of exodeviation, visual acuity, stereopsis with Titmus test and fusional status with Worth-4-dot test after surgery were analyzed. A surgical success was defined as postoperative angle of deviation less than 10 prism diopter (PD).
RESULTS
The patient mean age at the time of the operation was 7.9 years. The mean preoperative angle of exodeviation was 25.5 PD at far distance and 27.5 PD at near distance. The mean follow-up time was 22.9 months. The success rate of surgery was 81.6% at 6 months, 68.4% at 1 year and 60.5% on the last visit. Seventeen patients (44.7%) had stereopsis of 40 seconds and showed fusion at far and near distance after surgery. The stereopsis was worse than 100 seconds in 2 patients (5.3%), and fusion was maintained at only near distance in 15 patients (39.5%). In 7 patients (18.4%), the stereopsis decreased to 200 seconds or worse, or there was no fusion after surgery.
CONCLUSIONS
The recurrence of exodeviation was a major cause of the surgical failure in the intermittent exotropia with good preoperative binocular function. Moreover, binocular function may decrease postoperatively in intermittent exotropia with good preoperative binocular function, so careful follow-up may be required to maintain this function.

Keyword

Binocular function; Fusion; Intermittent exotropia; Stereopsis

MeSH Terms

Depth Perception
Exotropia
Follow-Up Studies
Humans
Recurrence
Telescopes
Visual Acuity

Figure

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  Figure 1. Distribution of preoperative angle of exodeviation.

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  Figure 2. Change of the angle of deviation during the follow-up after surgery for intermittent exotropia.

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  Figure 3. Postoperative streopsis (A) and fusion (B). * Fusion at far and near; † Fusion at near; ‡ No fusion.

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  Figure 4. Change of the postoperative angle of deviation be-tween maintained binocular vision group and reduced binoc-ular vision group. (A) Patients who maintained preoperative good binocular function after surgery (n = 17). (B) patients who decreased preoperative binocular function after surgery (n = 21).

Reference

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