Lateral Canthoplasty and Vertical Palpebral Fissure Enlargement for the Correction of Orbicularis Oculi Muscle Contracture in Facial Palsy.

Facial palsy can cause periocular deformities resulting in functional impairment and facial asymmetry. While lagophthalmos and ectropion are common sequelae, some patients develop paradoxical palpebral fissure narrowing due to contracture of the orbicularis oculi during recovery. We report the case of an 81-year-old woman with long-standing unilateral facial palsy who presented with lower eyelid elevation and reduced horizontal and vertical ocular dimensions. The patient was treated with a combined surgical approach consisting of complete lateral canthotomy, lateral canthoplasty, and posterior lamellar shortening for vertical palpebral fissure enlargement. At the 1-year follow-up, objective measurements demonstrated improvement in palpebral fissure width, margin reflex distance 2, exposure of the medial and lateral scleral triangles, and overall ocular symmetry. This case suggests that adapting cosmetic lateral canthoplasty techniques may be an effective option for correcting periocular asymmetry secondary to orbicularis oculi muscle contracture after facial palsy.