Secondary Blepharospasm Associated With Ocular Surface Disease
Secondary blepharospasm, where the normal protective blink reflex becomes excessive in certain ocular surface diseases, can similarly traumatize the ocular surface and exacerbate symptoms.4 Superior limbic keratoconjunctivitis is a chronic inflammatory condition where prolonged mechanical trauma from the eyelid leads to the development of marked inflammation of the upper tarsus and superior bulbar conjunctiva.4,5 Filamentary keratitis is a chronic condition of the ocular surface where epithelial and mucus filaments develop on the cornea (Fig. 1).4,6,7 Patients with these conditions present with chronic pain, photophobia, foreign body sensation secondary blepharospasm. This forceful and excessive eyelid blinking is not only debilitating but also results in further microtrauma to the ocular surface, further exacerbating the disease process.
Treatment for ocular surface disease typically involves therapies focused on increasing lubrication8,9 but generally does not address blink-related trauma to the ocular surface. Although conventional treatments may improve symptoms, for many patients, these modalities can be insufficient in providing relief. The authors have investigated the use of botulinum toxin-A as an adjunctive treatment for patients with refractory filamentary keratitis, with the intention of targeting the mechanical component of blink-related microtrauma (Fig. 2). Data including the type of tear dysfunction, prior and current treatments, examination findings indicating the number and location of filaments, number of botulinum injections, and treatment outcomes were reviewed.