False Nostril Entrapment (Alar Fold Entrapment) in Horses

False Nostril Entrapment (Alar Fold Entrapment)

Overview

The false nostril (nasal diverticulum) or alar fold can become entrapped or collapse during inspiration, creating a characteristic fluttering noise and increasing airway resistance. Most common in racehorses and high-performance horses. Similar in concept to epiglottic entrapment but affecting the external nares. Can be corrected surgically by resection of the alar fold or false nostril tissue.

Signs & Symptoms

Abnormal respiratory noise (fluttering, snoring) during exercise, especially at high speeds; noise is typically inspiratory; may vary with head position; reduced performance; noise is loudest at the nostril level (can be confirmed by holding the nostril open during exercise to eliminate the noise); diagnosis confirmed with dynamic endoscopy during exercise

Affected Structures

Frequently Asked Questions

What is False Nostril Entrapment (Alar Fold Entrapment) in horses?

The false nostril (nasal diverticulum) or alar fold can become entrapped or collapse during inspiration, creating a characteristic fluttering noise and increasing airway resistance. Most common in racehorses and high-performance horses. Similar in concept to epiglottic entrapment but affecting the external nares. Can be corrected surgically by resection of the alar fold or false nostril tissue.

What are the signs of False Nostril Entrapment (Alar Fold Entrapment)?

Abnormal respiratory noise (fluttering, snoring) during exercise, especially at high speeds; noise is typically inspiratory; may vary with head position; reduced performance; noise is loudest at the nostril level (can be confirmed by holding the nostril open during exercise to eliminate the noise); diagnosis confirmed with dynamic endoscopy during exercise