Metabolic/degenerative encephalopathies Flashcards
(22 cards)
What are lysosomal storage diseases?
A group of metabolic disorders resulting from enzyme deficiencies leading to the accumulation of toxic substances in cells
These diseases include glycoproteinoses, sphingolipidoses, and mucopolysaccharidoses.
What are common MRI findings in lysosomal storage diseases?
Extensive and diffuse hyperintensity of white matter on T2
* Poor white and gray matter distinction in forebrain and cerebellum
* Poor definition of sulci
* Bilaterally symmetric T2 hyperintensity in specific brain regions
* T1 hyperintensity in the internal capsule and basal nuclei
* No contrast enhancement.
What are the MRI findings associated with alpha-mannosidosis?
DWI decrease in apparent diffusion coefficient values of white and gray matter
* Increase in T2 values of white matter
* Decrease in magnetization transfer ratio
* Difference in MR spectroscopy spectral patterns.
What is globoid cell leukodystrophy (Krabbe’s disease)?
A sphingolipidosis affecting breeds such as WHWT, Cairn Terrier, and Beagle
It leads to specific MRI findings characteristic of white matter disease.
List the MRI findings for globoid cell leukodystrophy.
Diffuse, symmetric white matter disease
* Increased signal intensity in the corpus callosum on T1
* Symmetric T2 hyperintensity of multiple brain regions
* Decreased T2 intensity of thalamus and caudate nucleus
* Mild hydrocephalus.
What is the primary characteristic of gangliosidoses?
Excessive neuronal accumulation of ganglioside
GM-1 and GM-2 are specific types affecting various dog breeds and cats.
What are the MRI findings for GM-1 gangliosidosis?
Relative increase in gray matter with thinning of white matter
* Abnormal signal intensity of cerebral and cerebellar white matter on T2
* Diffuse T2 hyperintensity and brain atrophy.
* Absent or partial corpus callosum.
What are the MRI findings for GM-2 gangliosidosis?
Diffuse T2 hyperintensity and T1 hypointensity of subcortical cerebral white matter
* Bilaterally symmetric T2 hyperintensity of caudate nucleus
* Cerebral and cerebellar atrophy.
* Absent or partial corpus callosum.
What are the MRI findings for MPS I (Hurler syndrome)?
Cerebral ventricular enlargement and cortical atrophy at 12 months
* Abnormally small corpus callosum.
What is the MRI finding in MPS III (Sanfilippo syndrome type III B)?
MRI unremarkable
It may present with cerebellar signs.
What are the MRI findings associated with neuronal ceroid lipofuscinosis (Batten disease)?
Widening of cerebral sulci and cerebellar fissures
* Ventriculomegaly indicative of brain atrophy.
* Small corpus callosum.
What is the MRI finding for L-2-hydroxyglutaric aciduria?
Bilaterally symmetric gray matter abnormalities affecting multiple brain regions
* Abnormal swelling, T2 hyperintensity, and T1 iso or mild hypointensity.
What are the characteristics of hereditary polioencephalomyelopathies?
Mitochondrial encephalopathies resembling subacute necrotizing encephalomyelopathy
Affected breeds include Yorkshire terriers and Alaskan huskies.
What are the MRI findings for hepatic encephalopathy?
Brain atrophy
* Bilaterally symmetric T1 hyperintensity to the lentiform nuclei
* Extensive T2 hyperintense lesions along the cerebral cortex.
What is kernicterus?
Bilirubin encephalopathy characterized by MRI findings of hyperintensity in specific brain regions
It affects thalamus, caudate nuclei, and cerebral cortical gray matter.
What are the MRI findings for hypoglycemic encephalopathy?
Bilaterally symmetric lesions in caudate nuclei
* Strongly hyperintense on T2W and T2 FLAIR.
What are the MRI findings for thiamine deficiency in dogs?
T2, FLAIR, and post-contrast T1 hyperintensity of specific brain regions
It includes red nuclei and vestibular nuclei.
What are the MRI findings for hypocobalaminemic encephalopathy?
Bilateral symmetric lesions mostly affecting gray matter
* T2 hyperintense lesions in various brain regions.
What is myelinosis/osmotic demyelination syndrome?
A condition developing from rapid correction of chronic hyponatremia
Characterized by MRI findings of hyperintense lesions within thalamus and caudate nuclei.
What is the MRI finding for neurronal dystrophies?
Possible normal MRI +/- progressive generalized brain atrophy
Affects breeds like Rottweilers and collies.
What are the MRI findings for cerebellar cortical abiotrophy?
Small cerebellum
* Increase in fluid separating folia of cerebellum.
* Specific brain-to-cerebellum ratio cutoffs.
What are the MRI findings for idiopathic superficial neocortical degeneration?
Severe bilateral cerebrocortical atrophy
* Enlarged lateral and third ventricles.
