INTRODUCTION Granulomatous inflammation is a distinctive ...

By MRI, cholesteatomas are hypointense or isointense on T1-weighted images and hyperintense
on T2 images Yet, MRI is used when very specific problems involving surrounding soft tissues are
expected, like dural involvement or invasion, subdural or epidural abscess, herniated brain into
the mastoid cavity, inflammation of the membranous labyrinth or facial nerve, or sigmoid sinus
thrombosis (Chang et al., 1998).
Treatment
Medical therapy is not a viable treatment for cholesteatoma. Patients who refuse surgery or whose
medical condition makes a general anesthetic too hazardous should have the ear cleaned on a
regular and routine basis. Regular cleaning can help control infection and may slow growth, but it
will not stop further expansion and will not eliminate risk. Main treatment of cholesteatoma,
regardless of size, is complete surgical removal, with a recurrence rate of up to 50%, and often
result in hearing loss (Chang et al., 1998).
Cholesterol granuloma
Figure 28. CT scan showing Cholesteatoma on the left with
bone erosion and tegmen tympani dehiscence. (Mauricio et al.,
2005)
Cholesterol granuloma is not a neoplasm but a descriptive term used for a granulomatous
reaction to blood breakdown products, primarily cholesterol. They are thought to arise
secondarily following disease states where normally ventilated air-containing bony spaces are
obstructed, such as in chronic or acute otitis media, cholesteatoma, or mastoiditis (House and
Brackmann, 1982). Cholesterol granulomas occur most commonly in the pneumatized petrous
apex of the temporal bone but also may be seen in other pneumatized portions of the temporal
bone, including mastoid air cells and middle ear space (Lustig et al., 1998). They generally grow
silently, with clinical presentation after the lesion has caused bony destruction and compression of
cranial nerves V-VIII, structures within the inner ear, or the brainstem (Chang et al., 1998).
Symptoms can include headache, diplopia, vertigo, dizziness, hearing loss, and facial paralysis
(Lusting et al., 1998).
Cholesterol granulomas are usually cystic lesions with a thin brown-yellow fibrous capsule and
lumenal contents consisting of watery chocolate-colored fluid (Chang et al., 1998). Histologically,
they consist of an extensive granulomatous response with cholesterol crystals that are thought to
be the byproducts of blood degradation components (Rosenberg et al., 1986). The crystals are lost
with routine histologic processing leaving classic cholesterol clefts that are surrounded by
multinucleated giant cells, hemosiderin-laden and foamy macrophages, lymphocytes, plasma cells,
and abnormal blood vessels. In extensive lesions, there may be evidence of bone destruction
(Ferlito et al., 1997).
The primary lesion in the differential diagnosis with cholesterol granuloma is cholesteatoma