Endoscopic-guided diagnosis of and interventional stent placement for nasolacrimal duct obstruction in a horse.

The researchers successfully used endoscopy to diagnose and treat a horse’s chronic nasolacrimal duct (NLD) obstruction by placing a special stent. The process led to significant improvement in the horse’s ocular discharge and face sensitivity after the stent was removed. The study suggests that endoscopy and the placement of this type of stent offer effective alternatives to traditional invasive surgery for treating this condition.

Methodology

• The study was conducted on a 7-year-old Quarter horse gelding with a chronic NLD obstruction.
• The horse was put under general anesthesia for the process.
• The researchers conducted a retrograde nasolacrimal endoscopy using an 8.5 Fr Storz Flex XC ureteroscope introduced through the nasal punctum.
• About 20 cm from the nasal punctum, they identified an obstructive web of fibrous tissue.
• The researchers then sent a hydrophilic guidewire from the ventral lacrimal punctum to puncture the fibrotic tissue.
• A ureteral catheter was threaded over the guidewire to re-establish NLD patency.

Stent Placement

• Using the catheter, the horse’s NLD length was measured at 30 cm.
• The catheter was removed, and a Soft Ureteral Stent was threaded over the guidewire until the stent’s loops were visible at each end.
• The guidewire was then removed, and the stent’s loops were sutured in place.
• A month after the procedure, the stent was withdrawn.

Results & Conclusion

• Post-procedure follow-ups with the client revealed a substantial improvement in the quantity of the horse’s ocular discharge. Additionally, sensitivity around the animal’s face and ears had decreased.
• The findings indicate that endoscopy is not only a safe procedure but also an effective one for diagnosing NLD obstructions and assisting in interventional procedures.
• The study also suggests that introducing an indwelling ureteral stent could be a viable alternative to conventional, more invasive surgical procedures in treating equine NLD obstruction. This method offers temporary relief until a permanent solution or surgery can be arranged.