Neuro -- Neurodegenerative/basal Ganglia Disorders

Front 1

1. What is amyotrophic lateral sclerosis (ALS)?
2. What are the imaging findings?

Back 1

1. Progressive neurodegenerative illness characterized by presence of both upper and lower motor neuron dysfxn.
2.
- High T2SI in the corticospinal tracts bilaterally and symmetrically (look for hyperintensity in the region of the central sulcus, corona radiata, posterior limb of internal capsule, and cerebral peduncle) presumably representing Wallerian degeneration.
- Low SI within the gray matter of the motor cortex.

Front 2

What is the DDX of processes involving the basal ganglia?

Back 2

- Hypoxic ischemic injury (often involves the thalami prominently)
- Toxic exposure (may see globus pallidus necrosis)
- Metabolic dysfxn (metabolic errors usually present in younger pts)
- Wilson's disease
- Osmotic myelinolysis
- Encephalitis

Front 3

1. What is Creutzfeldt-Jakob disease?
2. What is the clinical presentation?
3. What are the imaging findings?

Back 3

1. Rare transmissable encephalopathy caused by an infectious particle called a prion.
2. Pts present with rapidly progressive dementia, ataxia, myoclonus, akinetic mutism.
3.
- Cerebral atrophy, especially involving the cortical and deep gray matter.
- Moderate to marked T2 hyperintensity in the basal ganglia and thalami.
- T1SI is normal

Front 4

1. What is Hallervorden-Spatz disease?
2. What are the imaging findings?

Back 4

1. Rare, autosomal recessive, neurodegenerative d/o with accumulation of brain iron.
2.
- Increased density due to dystrophic calcification in the globi pallidi.
- Striking low SI on T2WI in the globi pallidi.
- "Eye of the tiger": low SI surrounding a central area of high SI; may be transient.

Front 5

1. What is the etiology of Wilson's disease?
2. What are the clinical findings?
3. What are the imaging findings?
4. How can you differentiate Wilson's disease from other processes that involve the basal ganglia and deep gray nuclei?

Back 5

1. Caused by inborn error of copper metabolism that results in inability of the liver to excrete copper into bile.
2. Cirrhosis, basal ganglia degeneration, and corneal Kayser-Fleischer rings. Serum ceruloplasmin levels are markedly reduced.
3.
- High T2SI in the deep gray nuclei
- High T1SI in the globus pallidus and putamina.
- High T2SI in the WM of the brainstem, cerebellum, posterior limb of internal capsule, and hemispheric WM.
4. WM involvement suggests the diagnosis of Wilson's disease.

Front 6

1. What is the clinical triad of Huntington's disease?
2. What are the imaging findings?

Back 6

1. Chorea, Dementia, and personality disorder.
2.
- Brain atrophy
- Caudate volume loss with focal enlargement of the frontal horns.
- Increased T2SI in the caudate nuclei and putamina.

Front 7

Describe the various forms of cerebellar degeneration?

Back 7

1.
- Olivopontocerebellar atrophy: marked atrophy of the pons, vermis, and cerebellar hemispheres.
- Cerebello-olivary degeneration: spares brainstem except for olives.
- Cerebellar cortical degeneration: relative sparing of brainstem.
- Friedrich's ataxia: brainstem and cerebellum appear normal.
- Alcohol-induced acquired cerebellar degeneration: preferentially affects the vermis with sparing of brainstem.

Front 8

Increased T2 SI in basal ganglia/thalami

Back 8

ISCHEMIA
- may be 2/2 hypoxia or ischemia
- ischemic changes are most pronounced in the deep gray matter
- look for loss of gray-white matter junction, particularly at watershed areas.
- Etiologies of hypoxic-ischemic events = trauma (may be non-accidental, dehydration, and anoxic events)
CARBON MONOXIDE POISOINING:
- predominantly affects the globus pallidi but other deep gray matter structures can also be involved.
- periventricular white matter, centrum semiovale hyperintensity reflects diffuse demyelination.
- may have restricted diffusion.
WILSON DISEASE:
- 2/2 excessive copper accumulation in the brain (particularly the basal ganglia) resulting in chronic ischemia.
MITOCHONDRIAL DISORDER:
- MELAS (mitochondral myopathy, encephalopathy, lactic acidosis, and strokelike episodes): uncommon cause of stroke in children. Ischemic findings in nonvascular distribution. Chronic atrophy of basal ganglia and cortex with T2 hyperintensity.
KERNICTERUS
- encephalopathy due to deposition fo unconjugated bilirubin.
OSMOTIC DEMYELINATION
- 2/2 rapid correction of hyponatremia.

Front 9

Eye of the tiger

Back 9

This sign represents marked low signal intensity of the globus palladi on T2W MRI images. This low signal surrounds a central, small hyperintense area, producing the eye-of-the-tiger appearance [Figure 14].[16] The sign is seen in what was once known as Hallervorden-Spatz (HS) syndrome but is now called neurodegeneration with brain iron accumulation (NBIA) or pantothenate kinase II (PANC2)-associated neurodegeneration.[17] The marked low signal intensity of the globus palladi is a result of excessive iron accumulation and the central high signal is attributed to gliosis, increased water content, and neuronal loss with disintegration, vacuolization, and cavitation of the neuropil.