Medial Canthoplasty: Advanced Approaches and Outcomes

Medial canthoplasty is a specialized surgical procedure designed to reconstruct or reposition the medial canthus, often performed to correct eyelid malposition, improve function, or enhance aesthetics. It is commonly used in cases of trauma, congenital anomalies, or complications from previous surgeries. Achieving optimal results requires precision and a deep understanding of periocular anatomy.

Advancements in surgical techniques and materials have refined medial canthoplasty, leading to improved patient outcomes. Surgeons must carefully consider tissue alignment, tool selection, and postoperative care to ensure proper healing and eyelid orientation.

Key Anatomical Structures In The Medial Periocular Region

The medial periocular region is a complex anatomical area where multiple structures converge to support eyelid function, tear drainage, and facial symmetry. At the core is the medial canthus, the junction where the upper and lower eyelids meet. This area is stabilized by the medial canthal tendon (MCT), a fibrous structure that anchors the eyelids to the periosteum of the medial orbital wall. The MCT has two distinct limbs: the anterior limb, which attaches to the frontal process of the maxilla and provides tension to maintain eyelid positioning, and the posterior limb, which secures the eyelid margin against the globe for proper tear film distribution. Disruption of these attachments can lead to functional and aesthetic complications such as telecanthus or eyelid malposition.

Adjacent to the MCT is the lacrimal drainage system, which plays a fundamental role in tear outflow. The lacrimal puncta, located on the medial aspect of both upper and lower eyelid margins, lead into the canaliculi, merging at the common canaliculus before entering the lacrimal sac. The sac, housed within the lacrimal fossa, drains into the nasolacrimal duct. Any disruption to this system during medial canthoplasty can result in epiphora, or excessive tearing, requiring additional corrective procedures. Surgeons must be cautious to avoid iatrogenic injury to these delicate structures.

The orbicularis oculi muscle, particularly its pretarsal and preseptal components, also plays a significant role in medial canthal stability. This muscle encircles the eyelids and contributes to both voluntary and involuntary blinking, facilitating tear distribution and drainage. The medial portion interdigitates with the MCT, reinforcing eyelid tone and function. Surgical approaches that fail to preserve this muscle can lead to complications such as lagophthalmos or medial ectropion, impairing ocular surface protection.

Tissue Realignment Approaches

Achieving precise tissue realignment in medial canthoplasty requires an understanding of the biomechanical forces at play. The medial canthal tendon must be meticulously repositioned to restore both function and aesthetics. When disrupted due to trauma, congenital anomalies, or surgery, restoring its proper tension and orientation is paramount. Surgeons employ various fixation techniques, from direct suture reattachment to transnasal wiring, depending on the severity of displacement and tissue integrity. In cases of significant medial canthal widening, such as post-traumatic telecanthus, rigid fixation using non-absorbable sutures or miniplates may be necessary for long-term stability.

Suture material and anchoring technique significantly influence postoperative outcomes. Non-absorbable sutures, such as polyester or polypropylene, are preferred for their tensile strength and resistance to degradation, ensuring sustained support during healing. These sutures are typically anchored to the periosteum of the medial orbital rim to secure the repositioned tendon. Some surgeons use transnasal canthopexy, passing a suture through the nasal bridge for additional medial support. This method is particularly useful in cases of severe instability, distributing tension across a broader anatomical framework to reduce recurrent malposition.

Soft tissue realignment requires careful management of the orbicularis oculi muscle, as disruption of its medial fibers can lead to poor eyelid closure or malposition. Reapproximating the pretarsal and preseptal components is essential for maintaining eyelid tone and blink dynamics. In cases where medial ectropion is a concern, adjunctive procedures such as Z-plasty or V-Y advancement flaps may redistribute tension and enhance tissue mobility, preventing postoperative contracture and ensuring eyelid margin apposition to the globe.

Surgical Tools And Materials

Precision in medial canthoplasty depends on both surgical technique and the selection of appropriate instruments and materials. High-quality microsurgical tools ensure delicate tissue handling and minimize trauma to periocular structures. Fine-tipped forceps, like Adson or Bonn designs, allow for secure grasping of the medial canthal tendon and surrounding tissues without excessive compression. Needle holders with a locking mechanism, such as Castroviejo drivers, provide stability when placing sutures in confined spaces, reducing inadvertent tissue damage. Scalpels with ultra-sharp blades, typically No. 11 or No. 15, facilitate precise incisions while preserving the integrity of the lacrimal system.

Suture selection is crucial to surgical outcomes. Non-absorbable sutures, including 5-0 or 6-0 polypropylene or polyester, are preferred for tendon fixation due to their durability and resistance to enzymatic breakdown, providing long-term support. For soft tissue approximation, absorbable sutures such as 6-0 polyglactin (Vicryl) or poliglecaprone (Monocryl) allow for gradual healing without requiring suture removal. The choice between monofilament and braided sutures depends on procedural needs—monofilaments reduce inflammation and infection risk, while braided sutures offer superior knot security.

Hemostasis is essential to preventing postoperative complications such as hematoma formation or excessive scarring. Bipolar electrocautery is commonly used for precise coagulation with minimal thermal spread, preserving adjacent structures. Alternatively, hemostatic agents like oxidized regenerated cellulose (Surgicel) or fibrin sealants promote clot formation while minimizing inflammation. Tissue adhesives such as cyanoacrylate-based glues have also been explored as adjuncts for wound closure, particularly when minimizing the suture burden is desirable.

Postoperative Eyelid Orientation

Maintaining proper eyelid orientation following medial canthoplasty is essential for functional recovery and aesthetic balance. The immediate postoperative period requires close monitoring to ensure the eyelid margin remains in correct apposition to the globe, as minor deviations can lead to complications such as lagophthalmos or medial ectropion. Swelling in the early healing phase can temporarily alter eyelid positioning, making it important to distinguish transient edema-related changes from true malposition. Patients are often advised to keep the head elevated and apply cold compresses to minimize excessive inflammation, which can exert unwanted tension on repositioned structures.

Suture tension directly affects final eyelid alignment. Over-tightening can create an unnatural curvature or narrowing of the palpebral fissure, while insufficient support may result in recurrent laxity or widening of the medial canthal angle. A retrospective study published in Plastic and Reconstructive Surgery found that controlled suture placement with non-absorbable materials significantly reduced the incidence of medial eyelid malposition. These findings underscore the importance of intraoperative adjustments, where surgeons assess eyelid mobility and symmetry before finalizing fixation.