Kapitel 28 Imagine of the neurosystem

Question 1

What’s the main indication for using gradient echo?

Answer 1

Exploited to identify haemorrhages

Question 2

Briefly outline T1 vs T2 images?

Answer 2

T1 : Fat is white and fluid is dark

T2: Fat is dark and fluid is white.

FLAIR: like T2 but free flowing fluid (CSF) is dark.

Question 3

What type of contrasts are most often used for MRI, CT and scintigraphy respectively?

Answer 3

• CT: Iodine contrast 400-800 mg/kg
• MRI: Gadolinium chelates 0,1-0,15 mmol/kg
• Technetium (schinto)

Question 4

List some possible DDx for multifocal brain lesion with symmetrical distribution

Answer 4

• Metabolic or toxic disorders
• Nutrient deficiencies
• Hereditary/familial diseases
  –> these lesions are often neurodegenerative in nature.

Question 5

List Multifocal lesions with random distribution:

Answer 5

• Inflammation
• Metastatic neoplasm
• Multicentric neoplasm (eg. Lymphoma, histocytoc sarcoma)
• Small vessel infarction

Question 6

List some possible DDx for solitary brain lesion

Answer 6

• Neoplasm or neoplasm-like masses
• Granuloma
• Cysts
• Hematoma
• Abscess
• Ischemia/infarction

Question 7

Briefly outline a general MRI protocol (what sequences)?

Answer 7

• T1W before and after contrast
• T2W
• T2 FLAIR
• T2* W (STIR)