Determination of the Optimum Delivery Route for Botulinum Toxin A in Patients With Epiphora

Determination of the Optimum Delivery Route for the Intraglandular Administration of Botulinum Toxin A in Patients With Refractory Epiphora

Epiphora or excessive tearing is a significant disability for many affected patients diminishing their quality of life. There is a growing consensus that injection of Botulinum Toxin A (BTX-A) into the lacrimal gland provides relief in patients with hyperlacrimation secondary to aberrant regeneration of the 7th nerve, and limited evidence that it might help to reduce normal tear production in patients with epiphora from anatomic or functional outflow obstructions. BTX-A has been injected both transconjunctivally into the palpebral lobe of the lacrimal gland and transcutaneously into the orbital lobe. Both delivery routes have been successful in symptom relief with minimal complications. However, the effectiveness of transconjunctival versus transcutaneous injections has not been systematically compared. Also, whether the incidence of side effects is related to the dosage, concentration, or location of injection is unknown and has also not been systematically studied. The investigators plan to conduct a randomized clinical trial in patients with functional tearing comparing the transcutaneous delivery route of BTX-A to the transconjunctival delivery route (the most common route described in the literature). The investigators will also compare the side effect profile of each delivery route.

Inclusion Criteria:

• age over 18 years
• ability to give informed consent
• symptoms of epiphora in the setting of either a patent lacrimal outflow system or an obstructed outflow system for which the patient does not desire surgical therapy or is a poor surgical candidate

Exclusion Criteria:

• pregnancy
• ocular motility abnormalities
• prior ptosis, and/or strabismus surgery
• more than 2 mm of pre-existing ptosis
• inability to give informed consent
• history of a bleeding disorder