Low set ear 👂 with microtia in trisomy 21 fetal ultrasound

low-set ears (LSE) and microtia (underdeveloped external ear) are common findings in individuals with Trisomy 21 (Down Syndrome) and are often associated with hearing loss, so early audiological evaluation is crucial for timely intervention, with LSEs serving as a potential marker for chromosomal anomalies. 

Key Points:

• Prevalence in Down Syndrome: Many children with Down Syndrome exhibit low-set ears (upper ear tip below the eye line) and smaller pinnae (outer ear).
• Microtia: While LSE is common, microtia (a spectrum from small, malformed ears to complete absence) can also occur in syndromic cases, including Trisomy 21.
• Associated Hearing Loss: These ear anomalies significantly increase the risk of hearing impairment, often conductive hearing loss due to middle ear issues or ear canal problems, necessitating early testing.
• Clinical Significance: LSE is recognized as a potential ultrasound marker for chromosomal abnormalities, including Trisomy 21, prompting further investigation.
• Management: Early detection of hearing loss in Down Syndrome is vital, and microtia may require surgical correction later in childhood for both function and cosmetic reasons.