Hematomas, Herniations, And Hemorrhages

Question 1

Most common cerebral herniation pattern

Answer 1

Subfalcine herniation (falx herniation)

Question 2

Location of falx herniation

Answer 2

Displacement of brain beneath free edge of falx cerebri due to increased intracranial pressure

Question 3

Structures directly involved in tentorial herniation

Answer 3

Uncus

Midbrain

Question 4

Location of tentorial herniation (specifically uncal herniation)

Answer 4

Herniation of medial temporal lobe from middle into posterior fossa across tentorial opening

Uncus of temporal lobe is forced into gap between midbrain and edge of tentorium

Question 5

Location of tonsillar herniation

Answer 5

Cerebellar tonsils move downward through foramen magnum, possible compression of lower brainstem and upper cervical SC

Question 6

Boundaries of epidural hemorrhage

Answer 6

Dura and surrounding skull bone

Question 7

Boundaries of subdural hematoma

Answer 7

Blood accumulates between inner layer of dura mater and arachnoid mater

Question 8

Boundaries of subarachnoid hemorrhage

Answer 8

Blood accumulates between arachnoid mater and pia mater

Question 9

Cause/location of external hydrocephalus

Answer 9

Accumulation of CSF causing increase in volume in subarachnoid space (little to no ventricular dilation)

Question 10

Cause of internal hydrocephalus

Answer 10

CSF produced in ventricular system does not drain into subarachnoid space

Question 11

Location of internal hydrocephalus

Answer 11

Ventricle(s) proximal to obstruction

• obstruction in interventricular foramen —> 3rd ventricle choroid plexus ependyma
• obstruction in cerebral aqueduct —> midbrain astrocytoma
• median and lateral apertures —> arnold chiari malformation or dandy-walker cyst

Question 12

Cause of communicating hydrocephalus

Answer 12

Obstruction of narrow space between the tentorial notch and midbrain, usually due to adhesions or fibrosis in subarachnoid spaces from inflammation, cerebral edema, or uncal herniation

Question 13

Location of communicating hydrocephalus

Answer 13

Ventricles and infratentorial space

Question 14

Result of damage to dorsal root of SC

Answer 14

Diminished tone and reflexes

Question 15

Result of damage to posterior columns of SC

Answer 15

Ipsilateral loss of proprioceptive and 2-point tactile discrimination below the lesion

Question 16

Effect of damage to LSTT region of spinal cord

Answer 16

Contralateral loss of pain and temperature sensations 2 sensory dermatomes below lesion

Question 17

Effects of damage of lateral reticulospinal tract of SC

Answer 17

Horner’s syndrome above T1

Incontinence

Question 18

Deficits associated with lesion in anterior white commissure

Answer 18

Bilateral analgesia (usually of upper limbs)

Question 19

Effect of lesions of anterior horn of SC

Answer 19

LMN paralysis/paresis

Question 20

Effect of damage to lateral corticospinal tract (LCST) of SC

Answer 20

Ipsilateral UMN paralysis/paresis below lesion

Question 21

What CN is commonly affected in ALS?

Answer 21

Hypoglossal n.

Question 22

What disease often mimics ALS?

Answer 22

Lyme disease

Question 23

Diminished tone and reflexes may indicate damage to what area of the SC?

Answer 23

Dorsal roots

Question 24

Ipsilateral loss of proprioceptive and 2-point tactile discrimination below the lesion may indicate damage to what area of the SC?

Answer 24

Posterior columns

Question 25

Contralateral loss of pain and temperature sensations 2 sensory dermatomes below lesion may indicate damage to what area of the SC?

Answer 25

LSTT

Question 26

Horner’s syndrome (if above T1) and/or incontinence may indicate damage to what area of the SC?

Answer 26

Lateral reticulospinal tract

Question 27

Bilateral analgesia (usually of upper limbs) may indicate damage to what area of the SC?

Answer 27

Anterior white commissure

Question 28

LMN paralysis/paresis may indicate damage to what area of the SC?

Answer 28

Anterior horn

Question 29

Ipsilateral UMN paralysis/paresis below the lesion may indicate damage to what area of the SC?

Answer 29

Lateral corticospinal tract