J Korean Ophthalmol Soc.  2017 Jun;58(6):692-697. 10.3341/jkos.2017.58.6.692.

Factors Associated with Improved Surgical Outcomes in Recurrent Exotropia

• Kim MJ
• Kim SH

• KMID: 2382678
• DOI: http://doi.org/10.3341/jkos.2017.58.6.692

Abstract

PURPOSE
To investigate the factors that improve the success rate in patients with recurrent exotropia.
METHODS
A total of 60 patients who had undergone reoperation for recurrent exotropia and had at least 1 year of follow-up after surgery were included in this study. In total, 43 patients in the group with one-muscle surgery had undergone either unilateral medial rectus resection or unilateral lateral rectus recession, and the other 17 patients in the group with two-muscle surgery had undergone either bilateral medial rectus resection or lateral rectus muscle recession with medial rectus muscle resection of contralateral eye. The main outcome measure was final success rate, which was compared between the 2 groups.
RESULTS
In this study, 41 (95.3%) of 43 patients in the group with one-muscle surgery had successful outcomes, while 2 (4.7%) had undercorrection at the final follow-up examination. On the other hand, 10 (58.8%) of 17 patients in the group with two-muscle surgery had successful outcomes, 5 (29.4%) had undercorrection, and 2 (11.8%) had overcorrection. The success rates were significantly different between the 2 groups (p = 0.001). In addition, preoperative deviation had the largest area under the receiver operator characteristic (ROC) curve for the success rate and exhibited an optimal balance of both sensitivity and specificity using a cut-off value of 25 PD.
CONCLUSIONS
Final success rate was higher in the group with one-muscle surgery for the treatment of recurrent exotropia. Surgical outcomes are expected to be higher in patients with preoperative deviation of less than 25 PD.

Keyword

Intermittent exotropia; Recurrent exotropia; Reoperation; Success rate

MeSH Terms

Exotropia*
Follow-Up Studies
Hand
Humans
Outcome Assessment (Health Care)
Reoperation
Sensitivity and Specificity

Figure

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  Figure 1 Diagram of study patients. The group with one-muscle surgery and the group with two-muscle surgery. BLR = bilateral lateral rectus muscle; UMR = unilateral medial rectus muscle; BMR = bilateral medial rectus muscle; R&R = lateral rectus muscle recession and medial rectus muscle resection; ULR = unilateral lateral rectus muscle.

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  Figure 2 Receiver operator characteristic (ROC) graph showing the sensitivity and specificity of the various prism diopters. Preoperative deviation had the largest area under the ROC curve (0.855) for the success rates and exhibited an optimal balance of both sensitivity and specificity using a cut-off value of 24.5 PD (see Table 6).

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