Brainstem Flashcards Preview

IMS: Neuroanatomy > Brainstem > Flashcards

Flashcards in Brainstem Deck (13)
Loading flashcards...
1
Q

Medulla

Blood Supply

A

Medial region:

caudal ⟾ paramedial branches of anterior spinal artery

rostral ⟾ vertebral artery

Lateral region:

caudal ⟾ lateral branches of vertebral artery

rostral ⟾ posterior inferior cerebellar artery (PICA)

2
Q

Pons

Blood Supply

A

Medial regionparamedian branches of basilar artery

Lateral caudal regionanterior inferior cerebellar artery (AICA)

Lateral mid and rostral regioncircumferential branches of basilar artery

3
Q

Midbrain

Blood Supply

A

Medial regionparamedian branches of basilar artery

Lateral regionposterior cerebral artery (PCA)

Dorsal midbrain and dorsal rostral ponssuperior cerebellar artery (SCA)

4
Q

Cranial Nerve

Signs

A

Most ipsilateral to the lesion.

Good indication lesion location within brainstem.

Hypoglossal, vagus, or glossopharyngeal signs ⟾ medulla

Abducens, facial, or vestibulocochlear signs ⟾ caudal pons

Trigeminal nerve sign ⟾ mid-rostral pons

Trochlear or oculomotor signs ⟾ midbrain

5
Q

Long Tract Signs

A

Most contralateral to lesion.

Including medial lemniscus, STT, corticospinal tract, or corticobulbar tract.

Sx of lesion to descending sympathetic fibers are ipsilateral.

Provides little information about rostrocaudal level of the lesion.

6
Q

Medial Medullary Syndrome

(Dejerine’s)

A

Paramedian branches of anterior spinal artery caudally and vertebral arteries rostrally.

Long tract signs:

corticospinal tract and corticobulbar tract of pyramid ➡ contralateral spastic hemiparesis

medial lemniscus ➡ contralateral loss of fine touch and proprioception sensation from the body

Cranial nerve signs:

hypoglossal nerve/nucleus ➡ ipsilateral deviation of the tongue, dysarthria, fasciculations and atrophy

7
Q

Lateral Medullary Syndrome

(Wallenberg’s)

A

Posterior inferior cerebellar artery (PICA).

Long tract signs:

  • anterolateral system ➡ contralateral loss of pain and temperature sensation from the body
  • descending sympathetic fibers ➡ ipsilateral ptosis, miosis, anhidrosis (Horner’s syndrome)

Cranial nerve and other signs:

  • cranial nerve IX and X, nucleus ambiguus ➡ dysphagia, hoarseness, and decreased gag reflex
  • spinal nucleus and tract of V ➡ ipsilateral loss of pain from the face
  • cochlear and vestibular nuclei ➡ vertigo, nystagmus, nausea, and ipsilateral sensoryneural loss of hearing
  • solitari nucleus and tract ➡ ipsilateral loss of taste
  • inferior cerebellar peduncle (ICP) ➡ ipsilateral ataxia
8
Q

Medial Pontine Syndrome

Basal Pons Infarc Only

A

Paramedian branches of basilar artery.

Long tract signs:

  • corticospinal and corticobulbar tracts ➡ contralateral spastic hemiparesis

Cranial nerve and other signs:

  • abducens nerve ➡ ipsilateral medial strabismus
  • pontine nuclei and transverse pontine fibers ➡ contralateral ataxia
9
Q

Medial Pontine Syndrome

Basal Pons + Tegmentum Infarct

A

Paramedian branches of basilar artery.

Long tract signs:

  • corticospinal and corticobulbar tracts ➡ contralateral spastic hemiparesis
  • medial lemniscus ➡ contralateral loss of epicritic sensation

Cranial nerve and other signs:

  • abducens nerve ➡ ipsilateral medial strabismus
  • pontine nuclei and trasverse pontine fibers ➡ contralateral ataxia
  • facial colliculus + facial motor fibers ➡ ipsilateral facial weakness and medial strabismus
  • pontine nuclei and transverse pontine fibers ➡ contralateral ataxia
  • paramedian pontine reticular formation (PPRF) and medial longitudinal fasciculus (MLF) ➡ ipsilateral horizontal gaze paralysis and internuclear ophthalmoplegia
10
Q

Lateral Caudal Pontine Syndrome

A

AICA or circumferential branches of the basilar artery.

Long tract signs:

  • anterolateral system ➡ contralateral loss of pain/temp from body
  • descending sympathetic fibers ➡ ipsilateral ptosis, miosis, and anhidrosis (Horner’s syndrome)

Cranial nerve and other signs:

  • spinal nucleus and tract of V ➡ ipsilateral loss of pain and temp from face
  • facial nerve/nucleus ➡ ipsilateral face weakness, dry eye, loss of taste in anterior 2/3 of tongue
  • vestibulocochlear nerve/nuclei ➡ vertigo, nystagmus, and ipsilateral hearing loss
  • middle cerebellar peduncle (MCP) ➡ ipsilateral ataxia
11
Q

Lateral Mid-Rostral Pontine

Syndrome

A

Circumferential branches of basilar artery.

Long tract signs:

  • anterolateral system ➡ contralateral loss of pain and temperature sensation from body
  • descending sympathetic fibers ➡ ipsilateral ptosis, miosis, anhidrosis (Horner’s syndrome)

Cranial nerve and other signs:

  • trigeminal nerve/nuclei ➡
    • ipsilateral face hemianesthesia
    • weakness in muscles of mastication
    • jaw deviation towards lesion
    • diminished jaw reflex
    • loss of blink reflex
  • middle cerebellar peduncle (MCP) ➡ ataxia
12
Q

Basal Midbrain Syndrome

(Weber’s)

A

Paramedian branches of basilar artery and posterior cerebral artery (PCA).

Long tract signs:

  • corticospinal tract ➡ contralateral spastic hemiparesis
  • corticobulbar tract ➡ contralateral lower face weakness
    • drooping of the corner of the mouth

Cranial nerve and other signs:

  • oculomotor nerve:
    • somatic and parasympathetic motor fibers ➡ 3rd nerve palsy
      • ipsilateral lateral strabismus
      • ptosis
      • dilated pupil
      • ophthalmoplegia
      • loss of accomodation
      • loss of pupillary reflex
13
Q

Tegmentum + Basal Midbrain Syndrome

(Benedikt’s)

A

Lateral paramedian branches of basilar artery and posterior cerebral arteries.

Long tract signs:

  • corticospinal tract ➡ contralateral spastic hemiparesis
  • corticobulbar tract ➡ contralateral lower face weakness, drooping of corner of the mouth
  • superior cerebellar peduncle SCP and red nucleus ➡ contralateral ataxia, intention tremor, dysmetria
  • medial lemniscus ➡ contralateral loss of fine touch and proprioception sensation from the body

Cranial nerve and other signs:

  • oculomotor nerve/nucleus ➡ ipsilateral 3rd nerve palsy
    • ophthalmoplegia
    • lateral strabismus
    • ptosis
    • dilated pupil
    • loss of accomodation
    • loss of pupillary light reflex
  • substantia nigra and basal ganglia ➡ involuntary movement