Metabolic disorders

Question 1

What is the defect in PKU? What is the imaging?

Answer 1

Defective phenylalanine hydroxylase - increased phenylalanine which inhibits proteolipids

Progressive non specific white matter changes, more obvious on DWI

Question 2

What is the defect in maple-syrup disease? What is the imaging?

Answer 2

Failure to metabolize branched chain amino acids

White matter, basal ganglia, brainstem and internal capsule involvement with restricted diffusion

Question 3

What is the defect in homocystinuria? What is seen clinically?

Answer 3

Error in methionine metabolism leading to abnormal collagen and elastin

Multiple arterial and venous occlusions

Question 4

Dilatation of sylvian fissures and T2/FLAIR in basal ganglia and hemispheric WM suggests what

Answer 4

Glutaric Aciduria type 1

Question 5

Hypodense and swollen brainstem is seen in what amino acid disorder?

Answer 5

Maple syrup disease

Question 6

What are the deficiencies in MPS?

What are the imaging finding?

Answer 6

Defective metabolism of heparan, dermatan, and keratan

Nonspecific white matter abnormalites
Hydrocephalus
Macrocephaly
Cerebral atrophy
Perivascular dilation
Thickened skull and dura
ABNORMAL ODONTOID
THICKENED PLL in spine

Question 7

Dilated cystic lesions in the corpus callosum representing dilated corpus callosal spaces suggest what?

Answer 7

MPS

Question 8

What is MELAS?

What is MERRF?

What is Leigh disease?

What is menkes kinky hair disease?

Answer 8

Mitochondrial Myopathy, Encephalopathy, Lactic Acidosis, Strokes

Myocloinc Epilepsy with Ragged Red Fibers

X linked; subacute necrotized encephalomyelopathy due to deficient pyruvate kinase and cytochrome C oxidase

Large and dysfunctional mitochondria, accumulates copper, tortuous intracranial arteries

Question 9

What is the imaging in MELAS/MERRF?

Where specifically?

Answer 9

Large cerebral infarctions involving both white and grey matter

Parieto-occipital
Deep nuclei

Question 10

What is the imaging in Leigh disease?

Answer 10

Preferential and symmetrical involvement of deep gray matter nuclei (basal ganglia, periaqueductal grey matter, brain stem)

Question 11

Lentifrom nuclei (basal ganglia) T2 FLAIR signal with DWI suggests what?

Answer 11

Mitochondrial disorders and Glutaric aciduria type 2

Question 12

What is the mechanism of mitochondrial disorders?

Answer 12

Lack of ox phos results in increased lactate production

Question 13

What is the defect in Wilsons?

What is the progression of symptoms?

Answer 13

Ceruloplasmin - accumulates copper in liver, brain, corneas, bones, kidneys

Hepatic disease always precedes neurologic

Question 14

What are the imaging findings in Wilsons

Answer 14

Symmetrical spongy degeneration particularly involving the basal ganglia

T2/FLAIR signal in the basal ganglia bilaterally

Panda sign; normal low T2 signal in red nuclei and substantia nigra

can restrict diffusion

Question 15

What is the panda sign?

Answer 15

T2 FLAIR in the brainstem with preseration of normal low T2 in the red nuclei and substantia nigra

seen in Wilsons

Question 16

High T2/FLAIR in the MEDIAL thalamic and periaqueductal gray matter and contrast enhancement of mammillary bodies

Answer 16

Wernickes encephalopathy

Question 17

layered necrosis of corpus callosum, predominantly in the body

Answer 17

Marchiafava bignami

Question 18

What is the appearance of chronic liver disease in the brain?

Answer 18

HIGH T1 in basal ganglia, dorsal brainstem, and adenohypophysis due to manganese

Question 19

Diffuse high T2/FLAIR signal in the cerebellum suggests what

Answer 19

Wernickes

Question 20

What is the most common cause of basal ganglia calcification?

Answer 20

Idiopathic after age 10

Question 21

What diseases cause symmetric basal ganglia calcification?

Answer 21

Hypo/hyperparathyroidism

Fahr disease, postinflammatory conditions, postanoxia, AIDS in newborn, Cockayne disease