Complications of Endoscopic Sinus Surgery With Transient Isolated Medial Rectus Palsy

Isolated medial rectus palsy during endoscopic sinus surgery is an embarrassing event for surgeons and often results in persistent diplopia despite corrective surgery; therefore, its cause should be identified immediately. Because direct traumatic injury to the medial rectus always accompanies tearing of the periorbita and exposure of the orbital fat, other causes should be considered when no direct orbital injury is evident. Here, the authors report a case of local-anesthetic-induced transient isolated medial rectus palsy that recovered spontaneously after surgery.