1. TEMPORAL BONE ANOMALIES

2. Eac atresia M/Cpresentation is Small dysmorphic pinna. TYPES: Bony
Soft tissue
Mixed stenosis -membranous & bony portions
Middle ear findings depend on severity of atresia

3. 4 yrs old boy with complaints of deformed right auricle
4 yrs old boy with complaints of deformed right auricle. HRCT temporal bone shows atresia of right bony external auditory canal with deformed right auricle.

4. Right middle ear ossicles and inner ear appears normal

5. 1 year old boy
HRCT TEMPORAL BONE shows atresia of mixed bony-soft tissue EAC on left side with dysplastic malleus and incus and descending 7 th nerve canal noted within post. Aspect of bony septum of EAC atresia .

6. Bony inner ear appears normal and no obvius oval window atresia.

7. SEQUALE OF EAC ATRESIA Small, dysmorphic pinna
Middle ear findings depend on severity of atresia
Small middle ear
Fusion & rotation of malleus & incus
Dysmorphlc malleus & incus
Fusion of malleolar-incudal articulation
Oval window atresia may be associated
Congenital cholesteatoma behind atresia plate

8. SEQUALE OF EAC ATRESIA Facial nerve canal findings
Aberrant course of tympanic &mastoid portions of facial nerve common
Tympanic segment may be deluscent, overlying oval or round windows
Mastoid segment usually anteriorly displaced
May exit skull base into glenoid fossa, or lateral to styloid process
Inner ear findings
Inner ear &: lAC usually normal

9. COCHLEAR ANOMALY Michel deformity :complete labyrinthine aplasia
Cochlear aplasia:cochlea is completely absent
Common cavity deformity: no differentiation between the cochlea and the vestibule, both together forming a cystic cavity
Cochleo-vestibular hypoplasia: Both the cochlea and the vestibule - small in size
Incomplete partition type I (IP-I):cochlea lacks the entire modiolus and the cribriform area and appears cystic, along with a large cystic vestibule
Incomplete partition type II (IP-II) (Mondini deformity): The cochlea consists of 1.5 turns, with the middle and apical turns coalescing to form a cystic apex (due to a defect in the interscalar septum), along with a dilated vestibule and enlarged vestibular aqueduct

10. 4 yr old boy HRCT shows b/l cochlear dysplasia with incomplete cochlear turns