CT Temporal Bone
Ajay Malhotra
TMJ
Tensor tympani
Cochleariform process
Carotid canal
Eustachian tube
Epitympanum
Tensor tympani
Cochleariform process
Carotid canal
Mesotympanum
Tensor tympani
Cochleariform process
Carotid canal
Geniculate ganglion
Cochlea apex
Tegmen tympani
Koerner’s septum
Epitympanum
TM
Mesotympanum
Tensor tympani
Carotid canal
Malleus-Head
Lateral process
Manubrium
Cochlea
Scutum
Prussak’s space
Tegmen tympani
Koerner’s septum
TM
Mesotympanum
Scutum
Prussak’s space
Tensor tympani
Facial nerve
Malleus- Head
Manubrium
Incus- Body
Cochlea
Tegmen tympani
TM
Mesotympanum
Facial nerve
Cochlea-basal turn
Cochlear promontory
Tegmen tympani
Incus-Body
Long process
IAC
IAC
Crista falciformis
Facial nerve
Cochlea basal turn
Cochlear promontory
Scutum
Tegmen tympani
Incus-
Body
long process
Facial nerve
Crista falciformis
Scutum
Tegmen tympani
Vestibule
SSCC
Cochlea
Cochlear promontory
IAC
Epitympanum
Incus-short process
Incudal fossa
Stapes
Oval window
Cochlear promontory
Vestibule
Facial nerve
SSCC
LSCC
Arcuate eminence
IAC
Mesotympanum
Aditus ad antrum
Incudal fossa
Vestibule
Oval window
Round window niche
SSCC
LSCC
Arcuate eminence
Aditus ad antrum
IAC
EAC
Facial nerve
Vestibule
SCCC
LSCC
Jugular tubercle
Antrum
Sinus tympani
JF
Hypotympanum
HC
Vestibule
SSCC
LSCC
Facial nerve
Antrum
SSCC
LSCC
Facial nerve
Antrum
Vestibule
SSCC
LSCC
Facial nerve
Vestibular aqueduct
Mastoid
Antrum
PSCC
Vestibular aqueduct
Mandibular condyle
Caroticojugular spine
Facial nerve
Stylomastoid foramen
CC
JF
Mastoid
HC
Facial nerve
Caroticojugular spine
CC
JF
Facial nerve
CC
JF
Facial nerve
CC
JF
Glenoid fossa
Jugular spine
Pars vascularis
Pars nervosa
Eustachian tube
Tympanic membrane
Jugular plate
Facial nerve
CC
JF
Mesotympanum
Malleus-manubrium
Facial nerve
Eustachian tube
Cochlear aqueduct
Jugular plate
Facial recess
Pyramidal eminence
Sinus tympani
Cochlea-basal turn
CC
EAC
JF
Malleus-manubrium
Cochlea-basal turn
Cochlear promontory
Round window niche
Sinus tympani
Pyramidal eminence
Facial nerve
Pyramidal eminence
Sinus tympani
Stapedius muscle
Malleus
Incus-long process
Cochlea
Cochlear aqueduct
Tensor tympani
Stapes
Sinus tympani
Vestibule
Cochlea
Facial nerve
PSCC
Incudomalleal joint
Modiolus
Vestibule
Facial nerve
Modiolus
Epitympanum
Facial nerve
Geniculate ganglion
Incudomalleal joint
Cochlea
Vestibule
LSCC
Vestibular aqueduct
Aditus ad antrum
IAC
Antrum
Geniculate ganglion
Cochlea
Vestibule
Vestibular aqueduct
IAC
Antrum
Koerner’s
septum
Gasserian notch
SSCC
Anatomical Basis of Temporal Bone
Disease
VIIth CN Schwannoma
Hemangioma
Malignant parotid
Cholesteatoma
VIIIth CN Schwannoma
Meningioma
Glomus Tympanicum
CarcinomaSquamous/Adeno
Malignant Otitis Externa
Glomus jugulare
Schwannoma
Meningioma
VIIth Schwannoma
Hemangioma
Malignant parotid
Epidermoid
CG
Mucocele
ICA Aneurysm
Metastases
Plasmacytoma
Chondroid tumor
Cholesteatoma
Endolymphatic sac tumor
Key Difference:
• A cholesteatoma will have bony
erosion/expansion, especially of the scutum
and middle ear ossicles.
• Otitis media erodes the middle ear ossicles
only about 5% of the time.
Transverse fracture
Longitudinal fracture
Dx: Glomus Tympanicum
-Arise from glomus bodies
(paraganglioma tissue) associated
with CN IX’s tympanic branch called
Jacobson’s nerve.
Usually identified just lateral to the
cochlea.
The most common neoplasm in the
inferior part of the middle ear.
- Note the thin plate of bone between
the jugular bulb and the middle ear in
the hypotympanum. This is critical in
the evaluation of these tumors.
Should this bony plate be eroded, a
glomus jugulare with extension to the
middle ear becomes a likely
possibility and the management of
such a tumor is different.
Axial
Coronal
Thank You