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PERIOCULAR TENSION MANAGEMENT
PERIOCULAR TENSION MANAGEMENT
An intimate understanding of tension capacity of the eyelids relative to surrounding structures, and the varying degrees of laxity that come with age, is essential to avoid complications of ectropion and webbing. Highly sensitive tensional forces on the eyelid are created by the combined effects of thin and mobile skin of the eyelids and soft tissue, which are fixed to the bony orbit bilaterally and surrounded by thicker skin bound to the underlying retinaculum.
These unique relationships allow for the mobility of the eye and are necessary for the lids to open and close and for concentric movement of the orbicularis. However, this mobility of skin and soft tissue also reacts readily to external forces, including gravity and wound contraction. As the bony structures of the orbit change with age, the soft tissue and tendinous attachments loosen, creating a lower threshold for tensional forces to pull the lid away from the globe and can disrupt the function of the lids and lacrimal puncti. Similarly, the thin and mobile skin of the medial canthus, tethered by more firmly attached surrounding skin that facilitates the vertical movement of facial expression, moves readily to create a web. Knowledge and appreciation of these tensional forces is invaluable in maintaining function of the eye and avoiding the pitfalls of ectropion and webbing.
Preoperative assessment of the degree of laxity of the lower lid is typically done by assessing how far the lid distracts downward when gently pulled or how rapidly the lid snaps back when pulled away from the globe. Easy distraction or slow recoil indicates a lower threshold for vertical tension during lid repair and wound contraction. An appreciation for the degree of normal tension can be gained with experience. The degree of lid tension is assessed intraoperatively and postoperatively by having the patient simultaneously gaze upward and open the mouth widely. If the lid pulls away from the globe during this maximal vertical tension, additional support is needed, usually in the form of flap adjustment, suspension sutures, and/or canthopexy.