branchio-oto-renal dysplasia
Branchio-oto-renal (BOR) dysplasia, syndrome, or spectrum disorder is a rare syndromic disorder characterized by cervical branchial apparatus anomalies, ear malformations, and renal anomalies. If there are no renal anomalies, then it is more likely to be branchiootic dysplasia.
Pathology
When family history is absent, the diagnosis is established by 3 major criteria, or 2 major and 2 minor criteria . An affected individual with an affected first-degree relative only needs to meet one major criterion .
Major criteria, with examples :
- second branchial apparatus (arch/cleft) anomalies
- preauricular pits
- auricular malformation
- deafness (conductive, sensorineural, or mixed hearing impairment)
- renal anomalies
Minor criteria, with examples :
- preauricular tags
- external auditory canal anomalies
- atresia
- stenosis
- middle ear anomalies
- ossicular chain malformations
- inner ear anomalies
- cochlear anomalies, most commonly hypoplasia of the apical turn
- cochlear aperture stenosis
- dysplasia of lateral and/or posterior semicircular canals
- enlarged vestibular aqueduct
- abnormal course of the facial nerve
- other: facial asymmetry, palate abnormalities
Genetics
It carries an autosomal dominant inheritance. Most families with the branchio-oto-renal syndrome have mutations of the EYA1 gene, found on chromosome 8q.
Radiographic features
CT
Specific features on temporal bone CT include the following:
- "unwound cochlea," where the middle and apical turns are anteromedially rotated and displaced away from the basal turn
- medialized course of facial nerve (medial to cochlea)
Various additional findings on temporal bone CT are common :
- cochlear apical turn hypoplasia
- deficiency of the modiolus
- funnel-shaped internal auditory canal
- patulous Eustachian tube
Treatment and prognosis
Some individuals progress to end stage renal failure (ESRF) later in life.
Siehe auch:
Assoziationen und Differentialdiagnosen zu Branchio-oto-renales Syndrom:
