MUC5AC and laryngotracheoesophageal cleft: Sloughing of the superficial mucosa, flattening, vacuolization, and loss of mucin in the surface epithelium were identified in 73% (27/37), 51.4% (19/37), 65% (24/37), 62.2% (23/39) of CC; 29% (2/7), 86% (6/7), 43% (3/7), 71% (5/7) of LC while 33% (3/9), 11% (1/9), 22% (2/9), 33% (3/9) of MCi, respectively.