Page 67 - Feline diagnostic imaging

5.1 Diseases of the eline Skull 63

(a) (b)

(c) (d)

(e) (f) (g)

Figure 5.15 (a) The normal nasopharynx (arrows) should be seen as a uniform gas-filled structure dorsal to the soft palate (SP).
(b,c) A nasopharyngeal polyp (NP) can be seen when sufficiently large to replace the gas opacity, especially if the caudal margin
(arrows) is not superimposed by osseous anatomy. Larger polyps can displace the soft palate and produce signs associated with the
oropharynx and/or megaesophagus can be encountered. (d–g) Otic polyps are considered when no soft tissue is seen in nasal and
nasopharyngeal areas and there is abnormal soft tissue within the bullae (arrows). Unilateral polyps are more common, but this
patient had bilateral polyps confirmed with CT. Source: Images courtesy of Dr Anthony Fischetti, Animal Medical Center, and
Dr Merrilee Holland, Auburn University.

other inflammatory conditions associated with the naso- indicative of an inflammatory polyp [67]. CT is dependent
pharynx or middle ear. These modalities are superior in the on contrast enhancement of the mass for identification and
identification of the proliferative tissue that is typically therefore a poorly enhancing polyp can be more difficult to
contrast enhancing. A solid‐appearing mass‐like focus is identify or differentiate from other proliferative inflamma-
seen that undergoes predominantly peripheral or rim tory tissue. With the soft tissue contrast resolution of MRI,
enhancement in CT (Figure 5.16) [63–67]. Masses with a the polyp, regardless of its vascularity, is more easily distin-
stalk‐like attachment or asymmetric tympanic bulla wall guished from surrounding soft tissues or fluids, based on
thickening and/or expansion have also been found to be signal intensity and irrespective of contrast enhancement