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Gul Moonis,M.D. ¨ Pertinent anatomy, Department of Radiology clinical and imaging features of acute and Massachusetts Eye and Ear Infirmary chronic inflammatory Beth Israel Deaconess Medical Center lesions of the external Boston, MA auditory canal, and inner ear EAC ME IE ¨ Complications

Keratinizing Cuboid ep Stratified Squamous ep

EAC Normal lateral epithelial migration from TM to EAC ->self cleansing mechanism of keratin debrin

Local invasion of squamous epithelium into bony EAC, canal wall erosion , localized osteitis, sequestration of underlying bone

EAC Primary/Spontaneous Kerotosis Obturans Secondary-prior surgery /trauma/atresia /XRT Necrotizing Externa Clinical-U/L, older,chronic dull pain, otorrhea

Post XRT coronal Axial

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• Elderly Diabetics with otorrhea and severe otalgia, high mortality rate. • Pseudomonas aerogenosa • Skull Base osteomyelitis

• Expansile accumulation of keratin debris within EAC, scalloping but no erosion • Clinical-Young , B/l ,severe pain, conductive HL

T2 T1 post

• Osteomyelitis, prevertebral abscess • CT and MRI are complementary

ME

Acute Chronic Otomastoiditis EAC cholesteatoma MOE EAC Ca Cholesterol granuloma Cholesteatoma Tympanosclerosis

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¨ Fluid in • Children • Otalgia, fever,TM mastoid, red bulging • Strep, H flu middle ear • No imaging required • < 3 weeks ¨ Preserved trabeculae, cortex

REGIONAL/TEMPORAL INTRACRANIAL

¨ Post auricular • Coalescent • Meningitis erythema, tenderness, edema • Venous Sinus • Subperiosteal ¨ Inferiorly and Occlusion abscess posteriorly • Epidural Abscess displaced auricle • Bezold abscess • Petrous Apicitis • Brain Abscess

One Year Later

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Defect in Post auricular external cortex collection

¨ Analogous to coalescent mastoiditis

¨ Osteitis, septal/ T2 cortical disruption, meningitis V • 6 y/o female ¨ Gradinego’s • Headache, ear syndrome: Petroclinoid ligament Gruber lig pain, otitis media Otomastoiditis, 6th VI • CN VI and VII nerve palsy, deep palsy retroorbital pain

T1 post T1 post C/O Doug Phillips M.D.

✓ Direct Spread ✓ Thrombophlebitis of emissary vein

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Chronic Otomastoiditis:A variety of signs, symptoms, and physical findings that result from the long-term damage to the middle ear by infection and inflammation.

q Middle Ear Effusion q Middle Ear Effusion q Granulation tissue q Granulation tissue q Middle Ear Atelectasis/TM retraction q Middle Ear Atelectasis/TM retraction q Cholesterol Granuloma q Cholesterol Granuloma q Cholesteatoma q Cholesteatoma q Tympanosclerosis q Tympanosclerosis q Post inflammatory ossicular fixation q Post inflammatory ossicular fixation

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Eustachian tube dysfunction, negative pressure build- up,mucosal edema, blood vessel rupture, cholesterol deposition, FB 20 month old with CHL and blue TM giant cell reaction to cholesterol

T1 pre

45 year old female with asymmetric sudden ,,

T1pre T2 DWI

¨ CT- rounded ,expansile lesion PA ¨ MRI- expansile, T1 hyperintense, T2 heterogenous, hypointense rim ¨ DWI-variable

T2 T1 pre T1 pre

¨DDx - trapped fluid/ Petrous apex effusion ¨ T1 hypo or hyperintense, non destructive

Mastoid Cholesterol Granuloma Flair

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q Accumulation of keratinizing squamous epithelium in the middle ear cleft or other pneumatized portion of the temporal bone

MATRIX-Keratinizing squamous ep (produces keratin)

PERIMATRIX-connective tissue (resorbs bone)

Post op cholesterol granuloma CYST-keratin debris

Congenital Acquired 2% 98%

• Epithelial rests in the Pars Pars middle ear Flaccida Tensa • Pearly white mass 80% 20% behind an intact drum in a child with no previous history Otorrhea- of otorrhea, purulent if perfortion or otologic infected Invagination Theory- Chronic ET dysfunction->vaccum, chronic negative ME procedure Mixed hearing pressure->retraction pocket lined by surface epithelium of the TM. • CPA,Petrous Apex loss

Epithelial invasion theory -TM perforation ,squamous ep enters into the middle ear. Scutum, Lateral malleal fold,Pars Flaccida,Malleus neck

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Normal

CT-Lobulated expansile attic mass lateral to , scutal erosion, ossicle erosion 15 Year old male with longstanding right

Normal side

CT- lobulated ST medial to ossicles, posterior-facial recess,sinus tympani ,ossicle erosion

coronal axial

T1post T1post DWI Lateral Semicircular canal fistula T1 hypointense, T2 heterogeenously hyperintense ,Non enhancing Slowed Diffusion-non EPI coronal multishot HASTE

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coronal axial

Tegmen erosion

Eroded facial N canal

Normal Normal Normal

Meningoencephlocele

T2

Axial Coronal

T1 post DWI

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q MDCT is the mainstay for preop imaging q MRI for meningocele q MRI>CT for post op imaging T1 pre T1 post q Recurrent cholesteatoma (5-15%) RECURRENCE IN MASTOIDECTOMY CAVITY q scar/granulation tissue/fluid/inflammation q cholesterol granuloma q Post op Meningocele q Non EPI TSE based DWI techniques(HASTE/ BLADE)

Coronal multishot HASTE DWI T2

MASTOID RECURRENCE

MIDDLE CRANIAL FOSSA RECURRENCE

T2

T1post DWI DWI T2 DWI

ZYGOMATIC RECURRENCE

POST AURICULAR RECURRENCE

T2 DWI DWI T1post T2

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¨ Chronic inflammation-Excess deposition of acellular hyaline and calcium deposits within the submucous layer of the tympanic membrane / submucous membrane of the middle ear cavity ¨ Calcified scar tissue ¨ Most patients asymptomatic ¨ Conductive HL ¡ Post inflammatory ossicle fixation Myringosclerosis Chalky calcifications

EAC IE/IAC

Bell’s Palsy Ramsey Hunt Lyme Disease Labyrinthitis

Tympanosclerosis

¨ Facial paralysis ¨ Idiopathic- viral inflammation (?HSV) ¨ Very rapid onset, progress hrs - 3 weeks ¨ 80%improve ¨ Labyrinthine segment/Geniculate ganglion ¨ >3 weeks- look for other causes-Imaging

T1 post T1 post

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¨ Reactivation of zoster virus in the geniculate ganglion ¨ Systemic disease, immunocompromise, aging ¨ Burning pain ear, 1-4 days later- vesicular eruption, facial paralysis, hearing loss, vertigo T1 post ¨ MRI- enhancement of VII, VIII, labyrinth, pontine facial nucleus

T1 post

T1post T1post

• Middle ear infection, meningitis, autoimmune • Acute: CT normal, MR- faint enhancement • Chronic: Labyrinthitis Ossificans T1 post ✓ Fibrous stage T1 post CT normal MRI- loss of fluid signal on T2/CISS, enhancement ✓ Ossific stage-CT abnormal

T1 post T1 post

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3d CISS

3D CISS/FIESTA

Gad Gad

T1 post Initial CT Final CT

¨ EAC inflammation can mimic malignancy on imaging ¨ Petrous apex effusion should not be mistaken for cholesterol granuloma ¨ Cholesteatoma- bony changes( ossicle, tegmen, scutum), MRI (DWI)better for post op evaluation ¨ Persistent facial N enhancement , look for perineural involvement by tumor ¨ MRI is more sensitive for detecting LO http://www.bidmc.org/Research/Departments/Radiology/NeuroRSNA.aspx

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