Laser fenestration of the dorsal pharyngeal recess does not correct experimentally induced dorsal nasopharyngeal collapse in horses.
Authors: Jeong Sharon, Bond Stephanie, Bayly Warwick, Sole-Guitart Albert
Journal: Veterinary surgery : VS
Summary
# Editorial Summary: Laser Fenestration Ineffective for Dorsal Nasopharyngeal Collapse in Horses Nasopharyngeal collapse during exercise significantly compromises respiratory function, yet treatment options remain limited. Jeong and colleagues investigated whether laser fenestration of the dorsal pharyngeal recess could restore normal airway dynamics in six Standardbreds (five with experimentally induced dorsal collapse via bilateral glossopharyngeal neurectomy, one with naturally occurring disease), measuring V̇O₂max, minute ventilation, peak airflow rates and upper airway resistance during high-speed treadmill testing before collapse induction, immediately after collapse, and three weeks post-fenestration. Induction of moderate to severe collapse reliably decreased V̇O₂max by 63.5 mL/kg/min, minute ventilation by 78.8 L/min, and peak expiratory flow rates by 21.8 L/s—demonstrating substantial functional impairment—yet laser fenestration failed to reverse these deficits and paradoxically reduced peak inspiratory flow rates by 7.1 L/s, with only two of five horses showing subjective endoscopic improvement (the naturally occurring case being the exception). For practitioners managing horses with dorsal nasopharyngeal collapse, this work suggests that laser fenestration alone is unlikely to restore athletic respiratory capacity and should prompt reconsideration of current surgical protocols or investigation of alternative interventions addressing the underlying neuromotor dysfunction.
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Practical Takeaways
- •Laser fenestration of the dorsal pharyngeal recess should not be considered an effective treatment for dorsal nasopharyngeal collapse in horses based on this experimental evidence
- •Alternative surgical or medical approaches to managing NPC should be explored, as this procedure does not restore respiratory performance metrics
- •Clinicians should be cautious about applying this technique until further evidence supports its efficacy, particularly since endoscopic appearance may not correlate with functional improvement
Key Findings
- •Experimentally induced dorsal nasopharyngeal collapse significantly reduced VO2max by 63.5 mL/kg/min, minute ventilation by 78.8 L/min, and peak expiratory flow rates by 21.8 L/s compared to baseline
- •Laser fenestration of the dorsal pharyngeal recess failed to restore respiratory performance parameters after NPC induction, with peak inspiratory flow rates actually decreasing by 7.1 L/s post-surgery
- •Subjective endoscopic improvement was observed in only 2 of 5 horses following fenestration despite objective respiratory parameter decline
- •One naturally occurring case showed VO2max improvement of 12.9 mL/kg/min post-fenestration, contrasting with the experimental group findings