Anterior Segment Optical Coherence Tomography in Locating the Insertion of Horizontal Extraocular Muscles After Strabismus Surgery.

ABSTRACT

PURPOSE: To evaluate the accuracy of anterior segment optical coherence tomography (AS-OCT) for locating horizontal extraocular muscle (EOM) insertion after strabismus surgery. METHODS: The distance from the limbus to the postoperative muscle insertion was measured with calipers intraoperatively and by AS-OCT during the postoperative visit of adults undergoing strabismus surgery. Images were collected by masked technicians. Intraclass correlation coefficients (ICC) were used to evaluate the agreement between measurements. RESULTS: Twenty-eight patients were recruited. Measurements were taken from 31 eyes, including 17 lateral and 14 medial rectus muscles. EOM insertion was successfully identified by AS-OCT for 14 (45%) cases. The ICC between intra-operative and AS-OCT measurement was 0.886 when the distance from the limbus to the insertion of EOM was less than 8 mm and 0.001 when the distance from the limbus was between 8 and 10 mm. EOM insertion was undetectable if distance to the limbus was greater than 10 mm. CONCLUSIONS: AS-OCT can accurately identify post-surgical horizontal muscle insertion if the insertion is less than 8 mm from the limbus. [J Pediatr Ophthalmol Strabismus. 2021;58(1)62-65.].