Imaging

Question 1

What is the eye of the tiger sign?

Answer 1

The MRI demonstrates a characteristic ““eye of the tiger”” with low T2 signal centered in a high T2 signal area.

The eye of the tiger sign refers to abnormal low T2 signal on MRI (due to abnormal accumulation of iron) in the globus pallidus with a longitudinal stripe of high signal (due to gliosis and spongiosis) that can be seen in:

Hallervorden-Spatz syndrome: classical but not 100% pathognomonic, with other causes including progressive supranuclear palsy, early-onset levodopa-responsive parkinsonism, cortical–basal ganglionic degeneration)

Hallervorden Spatz syndrome, is also known as Neurodegeneration with brain iron accumulation. It is a progressive neurodegenerative movement disorder, with a common mutation PANK2.

The PANK2 gene is expressed ubiquitously, especially in the retina and the basal ganglia. The characteristic dystonic movements in PKAN2 may follow an initial period of apparent spasticity. Oromandibular dystonia is prominent.

Question 2

MRI findings of huntington’s disease?

Answer 2

Huntington disease presents with prominent dystonic features in children, rather than chorea, but the MRI usually shows atrophy of caudate as well as cortical atrophy.

Question 3

MRI findings of DYT1?

Answer 3

DYT1 typically has no MRI findings.

Question 4

Glutaric aciduria I MRI findings?

Answer 4

In glutaric aciduria I, onset of dystonia is earlier,

MRI shows necrotic lesions in basal ganglia and bitemporal atrophy.

Question 5

dopamine responsive dystonia MRI findings?

Answer 5

Patients with dopa-responsive dystonia often have early findings suggestive of spasticity, progressing to dystonia, but typically have normal MRI.”

Question 6

MRI findings of glutaric aciduria I

Answer 6

In glutaric aciduria I, onset of dystonia is earlier, MRI shows necrotic lesions in basal ganglia and bitemporal atrophy.

Question 7

What are the MRI findings for olivopontocerebellar atrophy?

Answer 7

The sagittal T1-weighted image shows a small pons and cerebellar atrophy. The axial T2-weighted image
through the pons shows the pons to be reduced in size. The axial image through the medulla and lower
cerebellum shows that the cerebellum is of high signal intensity relative to the more posteriorly placed occipital lobes and that the medullary olives are not normal in size. Thus the findings are that of cerebellar, pontine, and olivary atrophy.