Alleviation of Epiphora by Canaliculosinostomy into the Caudal Maxillary Sinus in the Horse.

The research article describes a surgical method called canaliculosinostomy into the caudal maxillary sinus conducted on horses for relieving chronic tearing (epiphora) due to nasolacrimal duct obstruction, as well as its positive long-term results in a tested group of five horses.

Explanation of the Research

• The surgical procedure called canaliculosinostomy was introduced as a way to alleviate chronic tearing, or epiphora, in horses. Epiphora is a condition caused typically by the blockage in the nasolacrimal duct. This surgery involves creating a new passage for the flow of tears from the medial corner of the eyes into the caudal maxillary sinus, located near the nostrils.
• This case study research involved five horses with confirmed nasolacrimal duct obstruction which were taken from a single equine hospital. The obstruction was confirmed through a Jones test or dacryocystography, both are diagnostic methods used to study the function or pathology of the tear ducts in the eyes.

Surgical Procedure

• The horses were anesthetized during the surgical procedure. A Steinmann pin and Jacob’s chuck, common instruments in orthopedic surgery, were used to create the new passage (canaliculosinostomy) for the flow of tears.
• A Foley catheter, a soft plastic or rubber tube, was inserted into the newly created passage. The bulb in the Foley was inflated and kept in the sinus while the other end was dragged through the upper eyelid and stitched to the skin on the head. The Foley catheter was kept in place for three weeks and then safely removed under sedation.

Results and Conclusions

• The study faced no intraoperative difficulties or complications. However, in one case, a horse managed to displace the Foley catheter three days after the surgery. Except for this incident, there were no other postoperative complications.
• Long term follow-up indicated that one horse was euthanatized for unrelated reasons 10 weeks after the surgery, by which time the tear condition (epiphora) was resolved. The remaining four horses also saw a complete resolution of epiphora, noted 24 to 46 months post-surgery, suggesting successful long-term outcomes from the procedure.
• The research concluded the simple technique of canaliculosinostomy into the caudal maxillary sinus as a successful surgical solution offering effective long-term results in treating epiphora in horses of various medical histories.