CT scan findings

1. UNSAFE CSOM, CHOLESTEATOMA
AND THEIR COMPLICATIONS
-DR. RUTVI PATEL
1st Year Radio-diagnosis Resident
Under Guidance of : DR. NALIN G. PATEL
Professor & HOD,
Radio-diagnosis Department

2. Normal HRCT Temporal Bone

3. MASTOIDITIS COALESCENT
MASTOIDITIS
Complete opacification of the middle ear cleft
(namely the epi, meso, and hypotympanum),
the mastoid antrum, and the mastoid air cells
by fluid density.
No bony erosive changes. (intact scutum,
ossicular chain & tegmen tympani).
Bulging right tympanic membrane.
Remarkable fluid-soft tissue density in left mastoid
air cells with the resorption of some mastoid air
cells septa and coalescence of the air cells.
Similar findings in right mastoid air cells but limited
to the tip of the mastoid are also seen.

4.  Right chronic otomastoiditis with petrous apicitis. (A, B) Soft tissue opacification in the
external and middle ear (meso- and hypotympanum) as well as in the mastoid cavity; however, no
bone erosion is seen. Note is made of pneumatisation of both petrous apices with presence of soft
tissue density on the right, suggestive of petrous apicitis (arrow in C).
Petrositis

5. CHOLESTEATOMA
Key HRCT findings of Cholesteatoma includes:
 Soft tissue opacification in the attic, aditus (non-dependentlocation) and can reachMastoid cells.
 Blunting / Erosion of thescutum
 Ossicular erosion – Long process of Incus erosion is common
 Presence of the diseasein Sinus Tympani – Sinus Cholesteatoma
 Complications like erosions of – Tegmen/ SemicircularCanal/Facial Nerve Canal/ Innerear

6.  (A, B) Right, pars flaccida Cholesteatoma with ossicular erosion. Coronal and axial HRCT
images of both temporal bones: thickened, right TM (arrowhead) with presence of nodular soft
tissue with convex margins in Prussak’s space (arrow) causing scutum blunting and ossicular
erosions. (C) Concomitant chronic mastoiditis. Contralateral normal ear for comparison.

7. MRI appearance of Cholesteatoma
T2W – High
T1W – Low
T1WI+C – No or Rim
enhancement

10. Complications
 Petrositis
 Extradural abscess
 Subdural abscess
 Meningitis
 Temporal lobe abscess > Cerebellar abscess
 Sigmoid sinus thrombosis

11. Post-operative status
(modified mastoidectomy) is
noted on right side along
with soft tissue component in
middle ear cavity, adjacent to
cochlea and associated mild
erosion of bony facial canal.
Fluid density with soft
tissue lesion is noted in left
middle ear cavity, attic,
aditus, mastoid antrum and
all air cells, with erosion of
bony Ossicles, scutum,
tegmen tympani and facial
canal.

12. Temporal lobe abscess as a complication of
Cholesteatoma
Abscess with internal hemorrhagic area and marked surrounding
edema is noted in left temporal lobe.

13. Temporal lobe Abscess
 Coronal T1 post
gadolinium (A) and axial
T2 (B) MR images
demonstrate an intra‐axial
left temporal lobe
peripherally enhancing
lesion (white asterisk),
adjacent dural enhancement
(white arrowhead) and a
peripheral rim of T2
hypointense signal (short
white arrow).
 On coronal (C) and axial
(D) CT, there is a soft tissue
mass in the left middle ear

14. Subdural & Cerebellar Abscess

15. Post contrast images of the same case
 Right middle ear and
mastoid effusion. Right
mastoid has loss of bone
with thinning of the wall.
 Extradural enhancing
collection along the
posterior and lateral right
cerebellum. Several
smaller enhancing
cerebellar collections are
associated with right
sigmoid and transverse
sinus thrombosis. Midline
shift and tonsillar
herniation due to
cerebellar
edema/subdural
collections.

16. Sigmoid Sinus Thrombosis
 Loss of normal signal void is seen involving the right transverse and
sigmoid sinuses extending to the proximal ipsilateral internal jugular
vein with signal appearances as hyperintense on T1w and FLAIR
images representing a subacute blood clot.

17. MENINGITIS
 1.FLAIR images show hyperintense material that fills diffusely the sulci of
both hemispheres. Post-contrast images show diffuse leptomeningeal
enhancement (better seen in 3.post-contrast axial FLAIR images than
post-2.contrast axial T1-SE images). T1-SE post-contrast images shows