[How to understand the excessive lateral rectus muscle recession]

Surgical treatments of intermittent exotropia include symmetric bilateral lateral rectus recession, symmetric bilateral medial rectus resection, asymmetric monocular lateral rectus recession and/or medial rectus resection, in which lateral rectus recession is the most common method. The maximum amount of lateral rectus recession, however, is still controversial. Bilateral lateral rectus recession 7-8 mm for 35(Δ)-40(Δ) exotropia and unilateral lateral rectus recession and medial rectus resection for exotropia larger than 40(Δ) are suggested by most doctor usually. But some other doctors advocated augmented bilateral lateral rectus recession (9-14 mm ) for exotropia larger than 50(Δ) or augmented unilateral lateral rectus recession for moderate angle exotropia (30(Δ)-35(Δ)), which brought confusion in practical clinical work. In this paper, we'll focus on the amount of lateral rectus recession, and discuss several common issues related to augmented lateral rectus recession, in order to provide references for the majority of clinicians.