Anatomy of the lateral canthal tendon

Objective. The purpose of this study was to clarify and describe the anatom y of the lateral canthal tendon. Knowledge of this anatomy is essential in selection of appropriate surgical procedures to restore orbital anatomy. Study design. Cross dissections were performed of the lateral orbital soft tissues from 21 preserved Caucasian cadaveric orbits. A block of the bony a ttachment of each lateral canthus was taken for histologic examination. Aft er anatomical exposure, the following measurements of the lateral canthus w ere made: (1) the distance from the midpoint of insertion of the lateral ca nthus at the lateral orbit to the zygomaticofrontal suture; (2) the horizon tal width of the lateral canthus, as measured from the lateral commissure t o the lateral orbit; (3) the vertical difference in height between the medi al canthal and lateral canthal insertions. Results. The mean midpoint of the lateral canthus insertion was 10.24 mm in ferior to the zygomaticofrontal suture (range, 5-15 mm). The mean horizonta l length of the lateral canthus from the lateral commissure to the lateral orbit was 7.52 mm (range, 2-12 mm). The mean vertical difference in height between the insertions of the medial canthus and the lateral canthus was 1. 35 mm (range, -2-4 mm), the lateral canthus being at a more superior point. Histologic examination of hematoxylineosin-stained slides showed that the fibers of the lateral canthus inserted into the periosteum but not beyond i t. Conclusions. The lateral canthal tendon attaches the upper and lower tarsal plates to Whitnall's tubercle inside the orbital rim deep to the septum. A precise knowledge of the periorbital anatomy will assist the surgeon in th e selection of appropriate surgical techniques that will provide for restor ation of this delicate anatomical configuration.