1. SYB 2 Marni Scheiner MS IV

2. What kind of image is this, and what do you see?

3. Subdural Hematoma • Typically following head trauma (falls/assaults) • May follow minor trauma • Acceleration/Deceleration Injury • Rupture of bridging veins • Accumulation of blood between the dura and arachnoid membranes • Common in elderly, babies (shaken baby syndrome) and alcoholics. http://www.sbsdefense.com/images/Meninges1.jpg

4. Subdural Hematoma • Signs and symptoms • As quick as 24 hrs, but may appear as much as 2 weeks later. • Vein hemorrhage= lower pressure than arteries (in epidural hematomas)=bleed more slowly • H/x of recent head injury/fall • LOC/ change in mental status/delerium/dementia • Seizure • Headache • N/V • Personality changes • Slurred speech, inability to speak • Ataxia • Blurred vision • If large enough, may cause signs of increased ICP or damage to part of the brain will be present.

5. Subdural Hematoma • 3 subtypes: (depend on speed of onset) • Acute • due to trauma • Most severe if associated with cerebral contusion • most lethal of all head injuries -- high mortality rate (20%-50%)if they are not rapidly treated with surgical decompression. • Subacute • 3-7 days after acute injury • Chronic • 2-3 weeks after acute injury • often after minor head trauma (50% pts have no identifiable cause) • Slow bleed, repeated minor bleeds, and usually self limited • Small subdural hematomas (<1cm wide) have much better outcomes than acute subdural bleeds

6. Radiographic Signs of Subdural Hematoma • MRI vs CT: • MRI better for size and effect on brain. • Non-contrast CT is primary means of making a diagnosis and eval for treatment. • Non-contrast Head CT: • General: • Crosses the suture lines, but not the dural reflections (DOES NOT CROSS THE MIDLINE) • Moderate/large size: cause midline shift. • Look for edema, may indicate future herniation • Usually no skull fracture

7. Radiographic- Subdural Noncontrast Head CT: • Acute: • hyperdense, crescentic shaped • Most common area: parietal region, and above the tentorium cerebelli • Sub-acute: • Isodense (with respect to brain) • More difficult to see with non-contrast. Contrast-enhanced CT or MRI recommended for imaging 48-72 hrs after injury. • Chronic: • Hypodense, easy to see on non-contrast head CT scan.

8. Pathophysiology • Collected bood--> draw in water osmotically-->brain expansion--> compression of brain tissue--> new bleeds/tearing other blood vessels. • Sometimes, arachnoid layer is torn--> CSF and blood both expand in the intracranial space--> increasing ICP. • If self-limited: The body gradually reabsorbs the clot and replaces it with granulation tissue.

9. Treatment • Depends on hematoma size and rate of growth. • Small subdural hematomas: • careful monitoring until the body heals itself • Large or symptomatic hematomas: • Craniotomy (open skull, remove blood clot, and control site of bleeding) • Post-op complications: • increased ICP, brain edema, bleeding, infection, and seizure.