Evaluation of two methods for topical application of contrast medium to the pharyngeal and laryngeal region of horses.

This research aimed to compare the effectiveness of two methods – oral and nasopharyngeal catheter – for applying radiopaque contrast medium to the pharyngeal and laryngeal regions of horses. The study found that the nasopharyngeal catheter was more effective, although further research with clinically ill horses is required.

Research Methodology

• The study was a crossover experiment involving five healthy adult horses.
• Each horse was administered radiopaque contrast medium – a material that enhances the contrast of structures or fluids within the body in medical imaging – either orally or via nasopharyngeal catheter.
• Radiographic examinations were conducted before and immediately after administration of the contrast medium to evaluate its distribution in the pharyngeal and laryngeal regions.
• The researchers also performed endoscopic examinations to verify the findings of the radiographic investigations.

Research Findings

• The radiographs obtained after administering the contrast through the nasopharyngeal catheter showed its presence in the nasopharynx, oropharynx, laryngopharynx, and larynx.
• In comparison, the radiographs obtained after oral administration showed the contrast medium mainly in the oropharynx and larynx.
• The endoscopic examinations supported these findings and were found to be more sensitive in detecting the contrast medium in the laryngopharynx. The detection rates were higher for both methods of administration.

Implications and Clinical Relevance

• The findings suggest that applying medication using a nasopharyngeal catheter would result in more effective topical distribution in the nasopharynx and larynx.
• However, more research should be done with horses suffering from clinical airway disease to validate these results.
• Oral administration, which did not consistently show detectable topical laryngeal distribution, could still be useful for treating certain conditions like palatitis.