Fig. 1
From: Morphometric characterisation of human tracheas: focus on cartilaginous ring variation
(Reproduced from Vanpeperstraete [1])
A diagrammatic representation of the various single and compound rings which were encountered in the lower part of the trachea in a human adult. The following are the assigned titles: (1) interrupted, (2) S-shaped, (3) L-shaped, (4) and (5) fenestrated, (6) Y-shaped or forked, (8) H-shaped, (9) U-shaped, (10) X-shaped, (11) A-shaped, (12) V-shaped, (13) and (14) M or W-shaped, (15) incomplete