Comparison of sinoscopic techniques for examining the rostral maxillary and ventral conchal sinuses of horses.

The research team conducted a descriptive study on horse cadavers to determine the most effective method for endoscopic examination of the ventral conchal and rostral maxillary sinuses. Findings suggest that fenestration of the ventral conchal bulla (VCB), in combination with conchofrontal sinus trephination, provided the most consistent access.

Methodology

In this research study, 40 equine cadaver heads were used to compare six different approaches for the endoscopic examination of the ventral conchal sinus (VCS) and rostral maxillary sinus (RMS) of horses. These approaches included:

• RMS’s rostral trephination (rostral RMS approach)
• RMS’s caudal trephination (caudal RMS approach)
• Trephination of the conchofrontal sinus (CFS), followed by RMS trephination using light to illuminate the maxillary bone (light-indicated RMS approach)
• Fenestration of the ventral conchal bulla (VCB) with CFS trephination (frontal VCB approach)
• Fenestration of the VCB with CMS trephination (caudal VCB approach)
• Fenestration of the VCB with trephinations of both CFS and CMS (combined VCB approach)

Results

The success of each method was determined by its ability to observe the rostral and caudal aspects of the VCS and RMS. In terms of successful observation:

• None could be seen from the rostral RMS approach and 40% from caudal RMS approach.
• A light-indicated RMS approach allowed for 8% rostral and 60% caudal visibilities.
• Frontal VCB approach saw 60% rostral and 73% caudal.
• The caudal VCB approach enabled visibility to both structures in 40% of cases.
• With the combined VCB approach, there were 68% rostral and 88% caudal success observations.

This indicates that the combined VCB approach was the most successful overall.

Conclusion

The study concluded that the most reliable technique for accessing both the rostral and caudal parts of the RMS and VCS for endoscopic examination is trephination into the CFS coupled with fenestration of the VCB. Techniques involving a trephine hole into the RMS were less effective, provided poor access to the VCS, and risked damaging the maxillary cheek teeth’s reserve crowns. Therefore, to conduct endoscopic observation of RMS and VCS, approaches involving fenestration of the VCB are highly recommended.