Korean J Ophthalmol.  2018 Apr;32(2):83-88. 10.3341/kjo.2017.0034.

Horizontal Extraocular Muscle and Scleral Anatomy in Children: A Swept-Source Anterior Segment Optical Coherence Tomography Study

• Han JY
• Lee DC
• Lee SY

• KMID: 2408946
• DOI: http://doi.org/10.3341/kjo.2017.0034

Abstract

PURPOSE
To evaluate the efficacy of anterior segment swept-source optical coherence tomography (SS-OCT) for examining horizontal extraocular muscle thickness, distance from the corneal limbus to the insertion of the horizontal extraocular muscle (limbus to insertion distance), and scleral thickness in Korean pediatric strabismus patients.
METHODS
This study included pediatric strabismus patients between 5 and 10 years of age. Children with any ocular disease other than strabismus or a history of ocular surgery were excluded. SS-OCT was used to measure horizontal extraocular muscle thickness, limbus to insertion distance, and scleral thickness. Eyes were classified into subgroups by sex, spherical equivalent of the refractive error (measured with cycloplegic refraction), and fixating/deviating eye.
RESULTS
One patient initially included in this study was excluded due to poor cooperation. Of the remaining 35 eyes of 20 patients, 19 eyes (54.3%) were from male patients and 16 eyes (45.7%) were from female patients. The mean patient age was 7.86 ± 1.38 years. Lateral scleral thickness was greater in male eyes than in female eyes (p = 0.048). No other differences were noted between male and female children. Additionally, there were no statistically significant differences between fixating and deviating eyes or among spherical equivalent groups for any parameter examined.
CONCLUSIONS
Anterior segment SS-OCT can successfully and comfortably measure horizontal extraocular muscle and scleral anatomy in children. These measurements may be helpful for treatment and follow-up of pediatric strabismus patients.

Keyword

Oculomotor muscle; Optical coherence tomography; Pediatric ophthalmology; Sclera; Strabismus

MeSH Terms

Child*
Female
Follow-Up Studies
Humans
Limbus Corneae
Male
Oculomotor Muscles
Refractive Errors
Sclera
Strabismus
Tomography, Optical Coherence*

Figure

• 

  Fig. 1 Swept-source optical coherence tomography (SS-OCT) image from a 9-year-old boy. (A) External view of the eye showing the medial rectus muscle. The horizontal line represents the part of the eye being imaged. (B) The SS-OCT image of the eye along the corresponding horizontal line in (A). Distance from the corneal limbus to insertion of medial rectus muscle (black arrow), scleral thickness (yellow arrow), and thickness of medial rectus muscle (orange arrow) are also shown and measured in microns with digital caliper.

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