Peds Radiology Case - Intracranial Hemorrhage

Question 1

List the 5 types of presentation of intracranial hemorrhage.

Answer 1

1. Subdural hematoma
2. Epidural hematoma
3. Subarachnoid hemorrhage
4. Intracerebral hemorrhage
5. Intraventricular hemorrhage

Question 2

What is the optimal imaging procedure to evaluate suspected intracranial hemorrhage?

Answer 2

Pre-contrast CT scan

Question 3

How does acute hematoma appear on pre-contrast CT imaging?

Answer 3

Area of high density

Question 4

CT can detect acute intracerebral blood as small as 2 mm - why?

Answer 4

Due to the contrast between high density of blood and low density of surroudning brain.

Question 5

List 10 etiologies for intracranial hemorrhage.

Answer 5

1. Trauma
2. Aneurysm/AVM rupture
3. Tumors
4. Stroke with reperfusion
5. Venous infarction
6. Vasculitis
7. Eclampsia
8. Amyloid angiopathy in elderly
9. Hypertension
10. Coagulopathy

Question 6

Define epidural hematoma.

Answer 6

Collection of blood between the inner table of the skull and the dura

Question 7

Common etiology of epidural hematoma?

Answer 7

Head trauma

Question 8

Why is epidural hematoma more common in chidlren?

Answer 8

Dura is not as well fixed to the skull in children as it is in adults

Question 9

Where are epidural hematomas commonly located and why?

Answer 9

Temporoparietal and parieto-occipital regions, because the fracture line occurs across the middle meningeal artery groove in 85-95% of cases

Question 10

Presentation of epidural hematoma?

Answer 10

Patients may present with a classic lucid interval with initial period of loss of consciousness followed by a lucid interval of no symptoms with subsequent neurological deterioration leading to coma

Question 11

Treatment of epidural hematoma?

Answer 11

Immediate neurosurgical evacuation, as the hematoma is the result of an arterial bleed

Question 12

What are the pre-contrast CT findings of an epidural hematoma?

Answer 12

Biconvex in shape
Acute blood is hyperdense (30-80 HU)
Does not cross suture lines (localized)
Mass effect due to hemorrhage and edema

Question 13

Define subdural hematoma.

Answer 13

Collection of blood between the dura and the arachnoid.

Question 14

Common etiologies of subdural hematoma?

Answer 14

Head trauma (child abuse), coagulopathy

Question 15

What causes a subdural hematoma?

Answer 15

Movement of the brain relative to the skull, as in an acceleration-deceleration injury, resulting in tearing of a cortical vein coursing within the subdural space

Question 16

Why is subdural hematoma more common in patients with brain atrophy?

Answer 16

Because the superficial veins are stretched over greater distances and are therefore more prone to rupture with rapid head movement

Question 17

Which is more common - epidural or subdural hematoma?

Answer 17

Subdural

Question 18

Which blood vessels are typically injured in subdural hematoma?

Answer 18

Veins (vs. epidural, which injures arteries) - this causes a delay in clinical signs

Question 19

How can subdural hematoma be classified by CT imaging?

Answer 19

Acute (0-2 days), subacute (3-14 days), and chronic (after 2 weeks)

Question 20

How does an acute subdural hematoma appear on CT?

Answer 20

Blood appears hyperdense (30-80 HU), crescentic shape (medial margin is not convex as in epidural hematoma), crosses suture lines and spreads diffusely over the brain surface, can cause significant mass effect leading to brain herniation

Question 21

How does a chronic subdural hematoma (aka hygroma) appear on CT?

Answer 21

Appears hypodense (lucent) as the cellular elements dissolve; blood products are absorbed with time and change to clear liquid.

Question 22

How does a subacute subdural hematoma appear on CT?

Answer 22

Isodense, can be easily missed

Question 23

Define subarachnoid hemorrhage.

Answer 23

Blood within the CSF subarachnoid space

Question 24

What causes subarachnoid hemorrhage?

Answer 24

Tears of small subarachnoid vessels either spontaneously or post-trauma

Question 25

How do subarachnoid hemorrhages classically present?

Answer 25

Atypical headaches that are abrupt in onset and severe ("worst headache of my life")

Question 26

What is the most common cause of subarachnoid hemorrhage? What is the most common cause of spontaneous subarachnoid hemorrhage?

Answer 26

Trauma; rupture of arterial aneurysms which release blood directly into the CSF

Question 27

How does subarachnoid hemorrhage appear on CT?

Answer 27

Blood in the sulci and subarachnoid space (normal sulci are filled with low density normal CSF and appear dark - sulci filled with blood appear hyperdense)

Question 28

Clinical effects of intracranial hemorrhage vary, but many patients exhibit ___.

Answer 28

Impaired consciousness

Question 29

What are the most common causes of intracerebral hemorrhage?

Answer 29

HTN, trauma, rupture of aneurysm or AVM, tumor-related, bleeding diatheses, illict drug use, and amyloid angiopathy in the elderly

Question 30

Intraventricular hemorrhages are most common in what patient population?

Answer 30

Premature infants (most occur in the first 72 hours after premature birth)

Question 31

In adults, what is the most common cause of intraventricular hemorrhage?

Answer 31

TBI

Question 32

In intraventricular hemorrhage, blood clots can block the flow of CSF and cause ___.

Answer 32

Hydrocephalus

Question 33

What three things appear hyperdense on CT in the brain?

Answer 33

Hemorrhage, calcium, and contrast (which is why we need to look at non-contrast CT for hemorrhage)

Question 34

List the steps in systematic evaluation of imaging study in suspected cases of intracranial hemorrhage.

Answer 34

1. Locate the site of hemorrhage (ventricle, sulci, brain parenchyma, peripheral surface of the brain, etc.) 2. Describe the shape of the density (round, biconvex, crescentic, etc.) 3. Look for edema around the hemorrhage manifested as a hypolucent area 4. Look for midline shift and brain herniation 5. Look for fractured skull and soft tissue hematomas, as many patients fall and sustain head injury.