Canaliculosinostomy as a Long-Term Treatment of Seven Horses for Permanent Obstruction of the Nasolacrimal Duct.

The research describes the use of canaliculosinostomy as a long-term procedure to treat the obstruction of the nasolacrimal duct in horses, and its outcomes including the improvement or resolution of epiphora (eye-watering due to tear overflow).

Methods

• The study used a case series method involving seven horses diagnosed with obstruction of the nasolacrimal duct, either unilateral or bilateral.
• The ventral lacrimal punctum and canaliculus of the affected horses were dilated with catheters of progressive diameters until a 14-gauge Jamshedi needle could be inserted through the sac into the caudal maxillary sinus.
• A plastic tube was then inserted into the sinus via the needle, which was then removed, leaving the tube behind.
• A hubless needle was utilized to pass the other end of the tube through the horse’s lower eyelid, leaving a segment of the tube exposed underneath the eyelid.
• The internal end of the tubing was then exteriorized through a trephine hole in the frontal sinus, and then tunneled underneath the skin next to the osteotomy.
• The tubing remained in the sinus for 5-6 weeks before being removed.

Results

• The procedure was performed under sedation and was reported to be performed easily.
• Of the seven horses, five experienced resolution of epiphora, and two reported improvement.

Conclusions

• Canaliculosinostomy as a method of diverting lacrimal secretions into the sinuses proved to be an effective solution to resolve or improve nasolacrimal duct obstruction-induced epiphora.
• It offers a good functional and cosmetic outcome as the horses were able to maintain general good health and appearance following the operation.
• Canaliculosinostomy can be carried out with the horse under sedation, making the operation a viable and easily applicable solution for obstructions of the nasolacrimal duct in horses.