Figure 1 : Image of external neck landmarks.

TMD: thyromental distance; HCD: hyoid to cricoid cartilage distance; SMD: sternomental distance; TCD: thyroid cricoid distance;
TW: thyroid width; TH: thyroid height; HMD: hyoid mental distance; OCD: occipital process to C7 distance.

Cattano et al.Journal of Anesthesiology and Clinical Science  2014 3:7DOI : 10.7243/2049-9752-3-7