malformations de l`oreille interne

lon
sil
s
u
o
R
doc
ue
ang
SFR L
MALFORMATIONS DE
L'OREILLE INTERNE
Rappel embryologique (Pearson, 1979)
•
•
•
•
•
Neurectoderme : v•sicule otique, labyrinthe
membraneux
MÄsoblaste : labyrinthe osseux, platine
•trier, espaces p•ri lymphatiques
I, IIes poches entoblastiques : trompe
eustache, cavit• tympanique, attique,
cavit•s post.
Ier arc branchial : marteau (t‚te, col),
enclume (corps, courte apophyse)
IIiÅme arc branchial : •trier, longue
apophyse enclume
lon
sil
s
u
o
R
doc
ue
ang
SFR L
MALFORMATIONS DU
LABYRINTHE OSSEUX
CLASSIFICATION (Jackler. 1987)
I - CochlÄe absente ou mal formÄe
– Aplasie labyrinthique compl„te (type Michel)
– Aplasie cochl•aire
– Hypoplasie cochl•aire
– Cochl•e mal form•e (Mondini)
– V•sicule unique : cochl•e et vestibule fusionn•s canaux normaux ou
mal form•s
II - Malformations avec cochlÄe normale
– Dysplasie vestibule + C.S. externe
– Dilatation de l'aqueduc du vestibule, canaux normaux, vestibule
normal ou dilat•
lon
sil
s
u
o
R
doc
ue
ang
SFR L
DILATATION AQUEDUC VESTIBULE
lon
sil
s
u
o
R
doc
ue
ang
SFR L
DYSPLASIE CSL - VESTIBULE
lon
sil
s
u
o
R
doc
ue
ang
SFR L
DYSPLASIE CSL - VESTIBULE
lon
sil
s
u
o
R
doc
ue
ang
SFR L
Syndrome de DI GEORGE( d•l•tion 22q 11)
lon
sil
s
u
o
R
doc
ue
ang
SFR L
Syndrome de CHARGE
lon
sil
s
u
o
R
doc
ue
ang
SFR L
Syndrome de charge
•
•
•
•
•
C:colobome
H:heart
R: retard mental
G:genito-urinaire
E:ear; ag•n•sie des canaux semi-circulaires
lon
sil
s
u
o
R
doc
ue
ang
SFR L
Malformations
de la
cochl•e
lon
sil
s
u
o
R
doc
ue
ang
SFR L
OTOCYSTE
lon
sil
s
u
o
R
doc
ue
ang
SFR L
SURDITE LIEE A L’X DFN3
PARTITION INCOMPLETE TYPE I, ABSENCE DE MODIOLUS
SURDITE DE TRANSMISSION DE OI, OREILLE GEYSER
lon
ang
SFR L
ue
sil
s
u
o
R
doc
PARTITION INCOMPLETE TYPE II
lon
sil
s
u
o
R
doc
ue
ang
SFR L
PARTITION INCOMPLETE TYPE II
lon
sil
s
u
o
R
doc
ue
ang
SFR L
MONDINI
DILATATION AQUEDUC VESTIBULE
PARTITION INCOMPLETE TYPE II
lon
sil
s
u
o
R
doc
ue
ang
SFR L
Bilan d’imagerie
• MALFORMATION OREILLE INTERNE
• IMPLANTATION :
– OREILLE INTERNE (liquides, aplasie)
– OREILLE GEYSER
– NERF COCHLEAIRE :
• St•nose du CAI<4mm, cochl•e isol•e (TDM)
• Ag•n•sie ou hypoplasie (IRM)
lon
sil
s
u
o
R
doc
ue
ang
SFR L
MALFORMATIONS OREILLE INTERNE
Stapes Gusher-Fistules de LCR trans-labyrinthique
•
•
•
Aqueduc de la cochlÄe
Rask-Anderson : - orifice cisternal : 4,2 mm 
- segment lat•ral : 0,14 mm 
Narcy, 1989 (TDM) : - segment lat•ral < 0,2 mm 
- pathologique > 1,5 mm 
CAI / Lamina Cribosa : modiolus absent
- orifice nerf vestibulaire sup•rieur
- canal du facial
Dysplasie labyrinthique sÄvÅre (Phelps, 1986)
- cochl•e mal form•e sans tour basal
- dilatation du vestibule +/- CSC externe
- d•fect platine de l'•trier
lon
sil
s
u
o
R
doc
ue
ang
SFR L
DILATATION AQUEDUC DE COCHLEE
STENOSE CAI
lon
sil
s
u
o
R
doc
ue
ang
SFR L
M•at acoustique interne
• Taille nerf cochl•aire > nerf vestibulaire sup. ou inf.
• Nerf cochl•aire > ou = nerf facial (64%)
• Sym•trie D/G (70%)
ht
ht
avant
lon
sil
s
u
o
R
doc
ue
ang
SFR L
CISS 3D
lon
sil
s
u
o
R
doc
ue
ang
SFR L
Ag•n•sie ou hypoplasie
du nerf cochl•aire
• Aplasie ou hypoplasie du nerf cochl•aire :
– avec st•nose CAI (2 cas); anomalies labyrinthe (2 cas)
– sans anomalies CAI ou labyrinthe (3cas)
Casselman, Radiology, 1997.
• Aplasie ou hypoplasie du nerf cochl•aire :
– anomalies labyrinthiques minimes : lamina cribosa
ferm•e cochl•e isol•e (=hypoplasie du canal
cochl•aire)
– modiolus d•ficient (5cas), large aqueduc du vestibule
– st•nose CAI (11/12 cas)
Glastonbury, AJNR, 2002.
lon
sil
s
u
o
R
doc
ue
ang
SFR L
IMPLANTS COCHLEAIRES
SURDITE NEUROSENSORIELLE ET TDM
Normal
Common cavity deformity
Mondini
Mondini and dilated vestibular aqueduct
Dilated vestibular aqueduc
Narrow IAM
Abnormal vestibule/semicircular canals
Abnormal cochlea, vestibule, and IAM
Cerebral abnormalities
Miscellaneous
Bamiou, Arch Dis Child, 2000.
71.6 %
0.9
2.6
3.4
5.1
2.6
6.0
4.3
0.9
2.6
lon
sil
s
u
o
R
doc
ue
ang
SFR L
MAR…
OD
lon
sil
s
u
o
R
doc
ue
ang
SFR L
MAR…OG
lon
sil
s
u
o
R
doc
ue
ang
SFR L
DHO…OD
lon
sil
s
u
o
R
doc
ue
ang
SFR L
DHO…OG
lon
sil
s
u
o
R
doc
ue
ang
SFR L
AUL..OD
lon
sil
s
u
o
R
doc
ue
ang
SFR L
AUL..OG
lon
sil
s
u
o
R
doc
ue
ang
SFR L
IMPLANTS COCHLEAIRES
IMAGERIE
1 - Imaging for cochlear implants
:
PHELPS. P, J. Laryngol. Otol. Suppl. 1999 ; 24 : 21-3
CT : malformation OI (20%), labyrinthite ossifiante
2 - Preoperative cochlear implant imaging : is MRI enough ?
ELLUL. S, Am. J. Otol. 2000 ; 21 : 528-33
– Perm•abilit• du tour basal : FSE - MRI = CT
– Malformations OI
IRM > CT
– Pr•sence du nerf cochl•aire IRM > CT
lon
sil
s
u
o
R
doc
ue
ang
SFR L
IMPLANTS COCHLEAIRES
OSSIFICATION COCHLEAIRE
• POST MENINGITIQUE
–
–
–
–
–
–
Si„ge : tour basal, fen‚tre ronde
Fibrose : labyrinthite scl•rosante
Ossification : labyrinthite ossifiante (73 %)
M•ningite virale ou bact•rienne
Bilat•rale ou unilat•rale asym•trique
D•lai d'ossification (0,5  16 ans)
YUNE, 1991
• AUTRES : traumatisme, ostospongiose.....
lon
sil
s
u
o
R
doc
ue
ang
SFR L
LABYRINTHITE OSSIFIANTE
lon
sil
s
u
o
R
doc
ue
ang
SFR L
LABYRINTHITE OSSIFIANTE
lon
sil
s
u
o
R
doc
ue
ang
SFR L
LABYRINTHITE OSSIFIANTE