Inflammatory/infectious Flashcards
(17 cards)
What are the general features of MRI findings in encephalitis compared to neoplasia?
More likely to have:
* Multifocality
* Irregular lesion shape
* Uniform T2 and FLAIR signal intensity
* Meningeal contrast enhancement
Less likely to have:
* Strong contrast enhancement
* Heterogeneous T2 and FLAIR intensity
* Mass effect
* Meningeal contrast
What are the types of meningeal enhancements observed in MRI?
Types include:
* Leptomeninges - extend into cerebral sulci
* Pachymeninges - dural enhancement which does not extend into sulci
What is the sensitivity of MRI for meningeal pathology?
Low sensitivity for meningeal pathology
What are common MRI findings in idiopathic or immune-mediated meningoencephalitis?
Common findings include:
* Multifocal lesions of white and gray matter
* Irregular lesion margins
* T2 and FLAIR hyperintensity
* T1 hypo or isointensity
* Variable contrast enhancement
What are the characteristics of necrotizing meningoencephalitis (NME) on MRI?
Common findings include:
* Multifocal, asymmetric lesions
* Ill-defined margins
* Loss of gray-white distinction
* Iso or mildly hypointense on T1
* Hyperintense on T2 and FLAIR
Which breeds are commonly affected by necrotizing meningoencephalitis (NME)?
Affected breeds include:
* Pug
* Maltese
* Chihuahua
* Pekingese
What are the MRI findings associated with necrotizing leukoencephalitis (NLE)?
Findings include:
* Multifocal asymmetric irregularly shaped lesions
* Predominantly affects subcortical white matter
* Hypointense on T1
* Hyperintense on T2 and FLAIR
What are the MRI findings in idiopathic eosinophilic meningoencephalitis?
Findings include:
* Widening of cerebral sulci
* Patchy cerebral T2 hyperintensity
* Diffuse T1 hypointensity
* Patchy or diffuse contrast enhancement
What are the MRI characteristics of feline infectious peritonitis?
Findings include:
* Meningeal, ependymal, or periventricular contrast enhancement
* Dilation of ventricles
* Strong contrast enhancement in most lesions
What are the MRI findings of cryptococcosis in dogs?
Findings include:
* Multifocal or isolated parenchymal and meningeal lesions
* T2 and FLAIR hyperintense
* T1 hypointense
* Well-defined lesions with granulomas or pseudocysts
What are the typical MRI findings for blastomycosis?
Findings include:
* Intra or extra-axial single or multifocal masses
* Usually T2 hyperintense
* Strong uniform contrast enhancement
What MRI findings are associated with rickettsial meningoencephalitis?
Findings include:
* Multifocal punctate lesions in caudate nuclei and thalamus
* T2 hyperintense and centrally T1 hypointense
* Occasionally contrast enhancing
What are the MRI findings of bacterial meningoencephalitis?
Findings include:
* Focal mass lesions
* T2 hyperintense and T1 hypointense
* Central necrotic or cystic center
* Thick peripheral rim contrast enhancement
What is the imaging characteristic of empyema?
Focal or regional thickening of the extra-axial space which is T2 and FLAIR hyperintense
What are the MRI findings associated with Neosporosis?
Findings include:
* Atrophy of cerebellum
* Multifocal T2 hyperintense lesions
* Possible concurrent spinal cord lesions
What are the MRI features of toxoplasmosis granulomas?
Features include:
* Intra-axial or extra-axial mass lesions
* T2 hyperintense and T1 iso or hypointense
* Strongly contrast enhancing
What are the MRI findings of parasitic meningoencephalitis?
Findings include:
* Cyst-like lesions containing T2 hyperintense, T1 hypointense fluid
* Possible mass effect
