cantholysis

Cantholysis is a surgical procedure that involves cutting the canthal tendon to release traction on the eyelids or to decompress orbital contents. It is most commonly performed as part of a lateral canthotomy and cantholysis, a rapid intervention used to reduce intraorbital pressure in orbital compartment syndrome and to safeguard vision.

Anatomy and technique: The lateral canthal tendon anchors the lateral edge of the eyelids to the lateral orbital rim and consists of anterior and posterior limbs. In cantholysis, the inferior limb, or inferior crus, of the lateral canthal tendon is typically divided to release the lower eyelid and increase orbital volume; the superior crus may be divided if additional release is required.

Indications: The primary indication is emergent decompression in orbital compartment syndrome to prevent optic nerve injury and vision loss. Cantholysis may also be employed to facilitate eyelid mobilization or repositioning during reconstructive eyelid procedures or in the management of cicatricial eyelid contractures.

Procedure and aftercare: The setting is often urgent and may use local anesthesia. A lateral canthotomy is followed by cutting the inferior crus of the lateral canthal tendon; in some cases, the superior crus is released as well. Hemostasis is achieved, and the eye is reassessed for signs of decompression. Care is taken to minimize the risk of long-term lid malposition or cosmetic deformity.

Outcomes and risks: When performed promptly for orbital decompression, cantholysis can relieve pressure and protect vision. Potential complications include lid malposition or laxity, canthal deformity, scarring, infection, and diplopia.

See also: orbital compartment syndrome, lateral canthal tendon, canthus.