Table 1. Summary of Weerda and Hunter et al classifications for microtia.

Weerda classification	Hunter et al classification
First degree dysplasia	Microtia, first degree
Most structures of a normal auricle are recognizable (minor deformities): (A) macrotia, (B) protruding ears, (C) cryptoptia, (D) absence of upper helix, (E) Small deformities, (F) colobomata, (G) lobule deformities, (H) cup ear deformities	Presence of all the normal ear components and the median longitudinal length more than 2 SD below the mean
Second degree dysplasia	Microtia, second degree
Some structures of a normal auricle are recognizable: (A) cup ear deformity type III and (B) miniear	Median longitudinal length of the ear more than 2 SD below the mean in the presence of some, but not all, parts of the normal ear
Third degree dysplasia	Microtia, third degree
None of the structures of a normal auricle are recognizable: (A) unilateral, (B) bilateral, and (C) anotia (peanut ears are included in this group)	Presence of some auricular structures, but none of these structures conforms to recognized ear components
	Anotia
	Complete absence of the ear

Abbreviation: SD, standard deviation.