Intro to Head CT

Renee B. Van Stavern, MD

Neurology

Normal head CT

Back

Front

Slice

thickness

Bone

Muscle

Hemorrhage

Contrast

Brain

Grey matter

White matter

Edema

CSF

Fat

Air

Attenuation

CT bone windows

CT Contrast

CT Contrast

Kindergarten Kop – It’s NOT a tuma. B. Mendelson

CT Advantages

Fast

Available

(Relatively) inexpensive

Sensitive for intracranial hemorrhage

CT Limitations

There is radiation

Bone artifact obscures visualization, especially

posterior fossa and spinal cord

Not very sensitive to intraparenchymal lesions or

brain edema

Noncontrast CT misses many abnormalities

Risk of allergic reaction to iodinated contrast media

http://www.radiology.wisc.edu/Med_Students/neuroradiology/NeuroRad/NeuroRad.htm

Cingulate gyrus

Brain Anatomy Review

The anatomic origin of the foot fetish. K. Clark

Major brainstem divisions 1 2 3

4

5

6

Diencephalon

http://www9.biostr.washington.edu/

1 2

3 4 5

http://www9.biostr.washington.edu/

Ventricular system

1 2 3

4

5

6 7 8

http://www9.biostr.washington.edu/

1 2 3 4

5

http://www.radiology.wisc.edu/Med_Students/neuroradiology/NeuroRad/NeuroRad.htm

Normal anatomy

1

2

2

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3

1

Note Brainstem Orientation!

CT Neuroanatomy Class

WU Neuroscience Tutorial

http://thalamus.wustl.edu/course/

Dorsal

Ventral

Ventral

Dorsal

http://medstat.med.utah.edu/kw/brain_atlas/brsc 1

2

3

4

1

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7

1

2

3

4

5

6

7

http://medstat.med.utah.edu/kw/brain_atlas/brsc/index.htm

1 2 3 4 5

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7

8 9

1

2

3

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5

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7 8

1

2

4

3

Creepy two eyes and a smiling face – C. Sumey

http://medstat.med.utah.edu/kw/brain_atlas/brsc/index.htm

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4 5 6

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10

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A calcified, ciliated, CSF-producing mucosal structure. C. Hou

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Arteries

1 2 3 4 5 6

7 8 9 10 11

Abnormal head CT

An order for reading scans

Patient, type of scan, indication, level

Quality of scan

Cranial and extracranial structures

(White spaces)

Ventricles, cisterns, and sulci

(Black spaces)

Brain parenchyma

Hemorrhage

Lesions

Describe lesions

Location

Density

Margins

Effects

Associated findings

Temporal progression

Differential diagnosis

Increased CT brain

attenuation

Hemorrhage (acute)

Calcium

Contrast

Metal

Decreased CT brain

attenuation

Ischemia

Infection

Neoplasm

Trauma

Edema

Hemorrhage (old)