Mondini-Dysplasie
Mondini malformation is a historical term used to describe an incomplete partition type II anomaly with large vestibular aqueduct.
Terminology
The term is often used inappropriately to describe any cochlear abnormality, rather than a specific type of cochlear hypoplasia. Thus, most would favor not using the term, except perhaps in cases where the findings exactly match those described by Mondini.
If any doubt it is best to just describe the anatomical abnormalities.
Clinical presentation
Patients have sensorineural hearing loss, which is usually bilateral. As the basal turn of the cochlea is intact, high-frequency hearing is generally preserved.
Pathology
The abnormality is thought to result from a relatively late insult during the 7 week of embryological development when most of the inner ear has already formed. Earlier insults result in more severe abnormalities (Michel deformity, cochlear aplasia and cochlear hypoplasia).
See classification of congenital cochlear anomalies.
There are only 1.5 turns to the cochlea instead of the expected 2.5. The interscalar septum between the middle and apical segments also fails to form leading to a confluent, sac-like cochlea.
Associations
Mondini dysplasia has been associated with thalidomide and rubella embryopathies as well as a number of syndromes:
- Pendred syndrome: bilateral sensorineural hearing loss and goiter
- CHARGE syndrome
- Klippel-Feil syndrome
- DiGeorge syndrome
- Wildervanck syndrome
Some publications have suggested a link between Mondini malformation and spontaneous CSF fistulae and meningitis; however, this appears to be only the case with more severe forms of cochlear hypoplasia, and not with a true isolated Mondini malformation .
Radiographic features
The Mondini abnormality consists of a triad :
- only 1.5 turns (instead of the normal 2.5 turns)
- normal basal turn with a cystic apex in place of the distal 1.5 turns
Additionally, complete or partial absence of the normal interscalar septum is also present, which can now be demonstrated on high-field MRI .
Treatment and prognosis
Hearing can be improved by implantation of a multichannel cochlear implant .
Complications
There is an increased risk of:
History and etymology
It was first described in Latin by Carlo Mondini (1729-1803), an Italian anatomist, in 1791 .
Siehe auch:
- Klippel-Feil-Syndrom
- Meningitis
- CHARGE-Syndrom
- Innenohr
- Mikrodeletionsyndrom 22q11
- perilymphatic fistula
- Wildervanck syndrome
- Anomalien der Cochlea
- Cochleahypoplasie
- Michel-Aplasie
- beidseitige Mondini-Dysplasie
und weiter:
Assoziationen und Differentialdiagnosen zu Mondini-Dysplasie:
