Anterior horizontal rectus anatomy in children with concomitant strabismus

Area of Science:

• Ophthalmology
• Pediatric Ophthalmology
• Strabismus Surgery

Background:

• Anterior ciliary vessel (ACV) counts, tendon width (TW), and limbus-to-insertion distance (LID) are critical anatomical parameters of the anterior horizontal rectus muscle.
• Limited data exist integrating these parameters in children with concomitant strabismus.

Purpose of the Study:

• To characterize ACV counts, TW, and LID in pediatric horizontal concomitant strabismus.
• To examine associations between these anatomical parameters and diagnosis/clinical variables.

Main Methods:

• Cross-sectional study of 227 children undergoing primary horizontal rectus surgery.
• Quantification of ACV bundles from intraoperative images; measurement of TW and LID.
• Comparisons between esotropia and exotropia, with adjustments for age and axial length (AL).

Main Results:

• ACV bundle patterns differed between medial rectus (MR) and lateral rectus (LR) but not by diagnosis.
• LR width was positively associated with age and AL.
• MR LID was shorter in esotropia compared to exotropia (P=0.022), even after adjustments.

Conclusions:

• Pediatric horizontal strabismus exhibits distinct anatomical features: more frequent LR ACV bundles than previously reported, age/AL influence on LR width, and shorter MR LID in esotropia.
• These findings offer a valuable surgical anatomical reference for pediatric strabismus.
• The data may inform future research on strabismus mechanisms and surgical outcomes.