Fig. 1

Cormack-Lehane classification. Grade I shows the entire glottis, grade II shows a part of the glottis, grade III shows the epiglottis but not the vocal cords, and grade IV shows the epiglottis is invisible
Cormack-Lehane classification. Grade I shows the entire glottis, grade II shows a part of the glottis, grade III shows the epiglottis but not the vocal cords, and grade IV shows the epiglottis is invisible