Evaluation of the effects of transendoscopic diode laser palatoplasty on clinical, histologic, magnetic resonance imaging, and biomechanical findings in horses.

The research investigates the effect of diode laser palatoplasty on horses’ soft palates by observing different factors such as scarring, edema, inflammation, and change in morphology captured through magnetic resonance imaging. The study also considered the changes in palate’s elasticity post-procedure.

Methodology

• The study involved 12 horses, six of which had undergone diode laser palatoplasty, while the other six acted as control.
• The treatment group was further divided into a low-dose treatment (1,209 to 1,224 J) and a high-dose treatment (2,302 to 2,420 J), with three horses in each group.
• The upper respiratory tracts of all treated horses were evaluated immediately after surgery and on days 2, 7, 14, 21, 30, and 45.
• Post-evaluation on day 45, the horses were euthanized and their heads were MRI scanned. The soft palate was then excised for further examination, which included a gross evaluation and a scoring for edema, inflammation, and scarring.
• These removed soft palates were further sectioned for histologic and biomechanical evaluations.

Results

• Endoscopic examination found a significant increase in scarring on the soft palate in the treated horses by day 7, along with a decrease in edema and inflammation.
• The data obtained from gross post-mortem aligned with the MRI findings.
• On day 45, both gross and histologic examinations showcased a significant increase in scarring, edema, and inflammation.
• High-dose-treated horses demonstrated a full-thickness injury of skeletal muscle and muscle fiber atrophy. Low-dose-treated horses showed superficial injury to the skeletal muscle upon histologic evaluation.
• A significant decrease in the soft palate elastic modulus was observed in the treated horses compared to the control group after surgery.

Conclusions

• The implementation of laser palatoplasty in the treatment of soft palates in horses resulted in fibrosis and skeletal muscle loss.
• Notably, the fibrosis did not correlate with an increase in the soft palate’s elastic modulus post-procedure. This indicates that while the procedure may cause scarring and muscle loss, it does not necessarily affect the palate’s elasticity.