Grading for Laryngeal Cleft:
Type I – Supraglottic interarytenoid cleft (above level of vocal folds)
Type II – Partial cricoid cleft, extending below level of vocal folds and partly through posterior lamina of cricoid (may be mucosal bridge covering partly absent cricoid arch)
Type III – Total cricoid cleft with or without extension into part of cervical tracheoesophageal wall
Type IV – Laryngoesophageal cleft involving major part of intrathoracic tracheoesophageal wall
Benjamin B, Inglis A. Minor congenital laryngeal clefts: diagnosis and classification. Ann Otol Rhinol Laryngol. 1989;98(6):417-20.
Contributed by Emily Zhang