Page 235 - Atlas of Small Animal CT and MRI

Neoplasia 225

Figure 2.8.1 Meningioma (Canine) CT

(a) CT, TP (b) CT+C, TP
13y MC West Highland White Terrier with central vestibular signs. A soft‐tissue mass, which is slightly hyperattenuating compared to
occipital lobe cortex, is identified in the right caudal fossa adjacent to the ventral margin of the os tentorium (a: arrow). The left side of
the cerebellum is hypoattenuating, suggesting the presence of perilesional edema (a: arrowhead). The mass intensely and uniformly
enhances following contrast administration and is well margined and broad based, indicating an extraaxial origin (b: arrow). Adjacent
cerebellum and brainstem are displaced and compressed (b: arrowheads). Postmortem examination confirmed a diagnosis of
meningioma.

Figure 2.8.2 Meningioma (Canine) MR
Adult dog of unknown gender, age, or breed. A
mildly T1 hyperintense, T2 hyperintense broad‐
based mass is present in the right temporopa-
rietal region causing a midline shift and
compression of the right lateral ventricle (a,b:
arrow). Adjacency to the calvarium and the
thin T2 hyperintense rim suggest an extraaxial
origin of the mass. Diffuse surrounding T1
hypointensity and T2 hyperintensity are
consistent with vasogenic edema (a,b: arrow-
heads). The mass intensely and uniformly
enhances following contrast administration,
and mass margins are reasonably well defined
(c,d). Dural tails, seen best on the dorsal plane
(a) T1, TP (b) T2, TP image, confirm the mass is extraaxial (d:
arrowheads). Wisner et al 2011. Reproduced
47
with permission from Wiley.

(c) T1+C, TP (d) T1+C, DP
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