Transendoscopic laser surgery to correct nasopharyngeal obstruction caused by head flexion in horses.

This research investigated the use of transendoscopic laser surgery to treat nasopharyngeal obstruction, a common issue affecting Warmblood horses, by removing part of the respiratory system’s structures that cause the obstruction. The study’s results suggest this surgical intervention can significantly increase the nasopharyngeal diameter, reducing or eliminating respiratory noise and improving the horses’ performance.

Objective and Methods

• The research’s objective was to establish the effectiveness of transendoscopic laser fenestration, a surgical method, in resolving nasopharyngeal obstructions in Warmblood horses. These obstructions often result in performance insufficiency and respiratory noise during poll flexion – a condition where the horse flexes its head.
• The study involved nine Warmblood horses that exhibited symptoms of nasopharyngeal obstruction. Diagnostic strategies used on these horses included endoscopy and radiology. Endoscopy revealed a dorsoventral (top-to-bottom) obstruction of the nasopharynx (the area of the throat behind the nose), which worsened during poll flexion.
• Meanwhile, radiographs taken from different head positions revealed that the affected horses had significantly smaller nasopharyngeal diameters during poll flexion compared to healthy horses.
• The surgical treatment entailed a transendoscopic laser fenestration of the median septum (a thin wall separating the guttural pouches in the horse’s throat) and removal of the salpingopharyngeal fold (a part of the horse’s respiratory tract) on the side that was worst affected.

Results

• Post-surgery evaluations were carried out three days later, involving exercise tests, endoscopy, and radiology. These assessments showed significant improvement, with the mean nasopharyngeal diameter increasing by 64% (from 1.67 ± 0.49 to 2.58 ± 0.61 cm). Moreover, the bothersome respiratory noise was lessened or absent in seven out of nine horses.
• A follow-up interview with horse owners performed six months after the surgery found that eight of the horses showed long-term improvements in performance.

Conclusion

• The study concludes that transendoscopic laser surgery is a promising low-risk treatment option for Warmblood horses suffering from nasopharyngeal obstruction caused by poll flexion. Following surgery, affected horses showed significant improvement in nasopharyngeal diameter and corresponding reduction or elimination of respiratory noise. The long-term benefits were noticeable in the majority of cases.