Surgical correction of an inferiorly displaced lateral rectus with equatorial myopexy.

Orbital connective tissue normally loses strength and rigidity during aging. The lateral rectus pulley that surrounds and directs the lateral rectus path has the flimsiest support and can sag too far inferiorly, resulting in significantly reduced abducting force and secondary esotropia. This displacement is worsened by a weakened lateral rectus-superior rectus band from high myopia. Augmented medial rectus recessions can correct the esotropia, but long-term results may be less predictable because the underlying anatomic abnormality, the sagging lateral rectus muscle, has not been addressed. Lateral rectus equatorial myopexy is a straightforward technique that uses a permanent scleral suture to fixate the posterior lateral rectus belly into its correct anatomic position. The response to surgery depends on the magnitude of lateral rectus sag and is somewhat self-titrating-more sag correlates with both larger distance esotropia and thus larger corrections from lateral rectus equatorial myopexy alone-but larger deviations often require repositioning of muscle insertions to compensate for secondary changes to muscle lengths and tension.