Page 277 - Atlas of Small Animal CT and MRI

Cranial Nerves 267

Figure 2.10.2 Idiopathic Trigeminal Neuropathy (Canine) MR
3y F Pug with a 6‐day history of dropped jaw.
Neurologic deficits were limited to cranial
nerve V motor function bilaterally. The mandi­
bular branches of the fifth cranial nerves are
symmetrically enlarged and are T1 and T2 isoin­
tense on unenhanced images (a,b: arrows).
Both nerves uniformly and intensely contrast
enhance, defining enlarged intracranial and
distal components that exit the base of the
skull through the oval foramina (c,d: arrows).
Image d is a parasagittal view of one of the
mandibular nerves. A diagnosis of idiopathic
trigeminal neuropathy was made in this patient
based on the lack of any identifiable cause for
(a) T1, TP (b) T2, TP the neuropathy and gradual improvement with
supportive care.

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

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