Injection of Botulinum Toxin A in the Lacrimal Gland for Treatment of Epiphora in Crocodile Tears Syndrome - A Case Report.

[PURPOSE] Crocodile tears syndrome is a rare autonomic synkinesia, in which patients tear excessively in response to salivary stimuli. It usually occurs after idiopathic or traumatic facial palsy, as a result of aberrant reinnervation of the lacrimal gland by salivary efferent fibers from either the seventh or ninth cranial nerve.

[PATIENTS AND METHODS] We report the case of a 54-year-old woman, with a history of left Bell's palsy, who attended our ophthalmology clinic due to epiphora of the left eye while eating or speaking, for 6 months.

[RESULTS] The ophthalmologic evaluation revealed a mild weakening of the frontal and left orbicularis oculi muscles without lagophthalmos. No other abnormalities were found, namely ocular surface swelling, ectropion, or obstruction of the lacrimal outflow system. Schirmer test II in the left eye increased from 12 to 23 mm while the patient was chewing. All these clues led to the diagnosis of crocodile tears syndrome and treatment with botulinum toxin A injection was proposed. One month after the injection of the palpebral lobe of the left lacrimal gland with 6 units of botulinum toxin A, the patient reported an almost complete resolution of the complaints, stated by a decrease in Munk scale and Lac-Q scores. Six months after injection, the patient conveyed recurrence of symptoms and a new treatment session was performed with comparable results.

[CONCLUSION] Since crocodile tears syndrome is rare, it is crucial to increase awareness and knowledge about it among ophthalmologists and other medical doctors. Botulinum toxin is a safe and effective treatment modality, dramatically improving these patients' quality of life.