Abnormal Ears
Roya Sohaey, MD
DIFFERENTIAL DIAGNOSIS
Common
Low Set Ears
Deficient or Absent Ear
Less Common
Lop Ear
Protruding Ear
ESSENTIAL INFORMATION
Key Differential Diagnosis Issues
Normal ear position
Top of helix is at the inner canthi eye level
Ear size evaluation
Ear length = 1/3 biparietal diameter
Ear width is more variable
Use 3D to evaluate morphology
Helix is most external curve of auricle
Antihelix is Y-shaped internal auricle
Tragus lies over external meatus
Antitragus faces tragus
Helpful Clues for Common Diagnoses
Low Set Ears
Top of helix is lower than inner canthi line
Associated with micrognathia
Treacher Collins syndrome
Nager syndrome
Pierre Robin syndrome
Aneuploidy
Deficient or Absent Ear
Microtia = small ears
With or without absent auricular components
Anotia = no external ears
Helpful Clues for Less Common Diagnoses
Lop Ear
Deformed ear cartilage
Top of ear curls downward
Often isolated
Autosomal dominant inheritance described
Associated with other anomalies
Anencephaly
Other syndromes with cartilage defects
Protruding Ear
Ear protrudes > 25° from head
Most often idiopathic
Show ears are not low set
Other Essential Information
Association with aneuploidy
