questions 2

Brainstem

Topic updated on 10/26/16 4:44pm

Overview
                
 
Introduction
  • The brainstem is composed of the midbrain, pons, and medulla
Brainstem Structures
Structure Cranial Nerves Comments

Midbrain (Mesencephalon)

  • Oculomotor nerve (CN III)
  • Trochlear nerve (CN IV)
  • Reticular activating system
    • involved in arousal and alertness
    • lesion can lead to coma
  • Superior colliculus
    • conjugate vertical gaze center
  • Inferior colliculus
    • auditory information processor
  • Parinaud's syndrome
    • due to compression of dorsal midbrain and pretectal area (e.g., pinealoma, hydrocephalus)
      • lesions the superior colliculus
    • conjugate vertical gaze palsy

Pons (Metencephalon)

  • Trigeminal nerve (CN V)
  • Abducens nerve (CN VI)
  • Facial nerve (CN VII)
  • Vestibulocochlear nerve (CN VIII)
  • Medial longitudinal fasciculus
    • lesion leads to intranuclear ophthalmoplegia (INO)

Medulla (Myelencephalon)

  • Glossopharyngeal nerve (CN IX)
  • Vagus nerve (CN X)
  • Hypoglossal nerve (CN XII)
  • Vasomotor center
  • Respiratory center
  • Area postrema
    • incomplete blood-brain barrier
    • chemoreception of toxins
      • triggers nausea and vomiting
  • Medial lemniscus
    • formed by decussating fibers of the nucleus gracillis and cuneatus
  • Pyramids
    • contain corticospinal tracts
      • most decussate in the caudal medulla
  • Olives
    • send fibers through the inferior cerebellar peduncle
    • distinguishing feature of medulla


  RATE CONTENT
4.0
AVERAGE 4.0 of 3 RATINGS

Qbank (2 Questions)

TAG
(M1.NE.11) You are called to see a chemotherapy patient who is complaining of severe nausea. This patient is a 52-year-old male with acute lymphoblastic leukemia (ALL) who began his first cycle of chemotherapy 2 days ago. Which of the following structures is involved in the pathway responsible for this patient's nausea? Topic Review Topic

1. Medulla oblongata
2. Medial geniculate nucleus
3. Lateral geniculate nucleus
4. Posterior hypothalamus
5. Ventral posterolateral nucleus

PREFERRED RESPONSE ▶
TAG
(M1.NE.77) A 25-year-old male presents to his primary doctor with difficulty sleeping. On exam, he is noted to have impaired upgaze bilaterally, although the rest of his ocular movements are intact. On pupillary exam, both pupils accommodate, but do not react to light. What is the most likely cause of his symptoms? Topic Review Topic
FIGURES: A          

1. Frontal lobe cavernoma
2. Craniopharyngioma
3. Pinealoma
4. Melanoma with temporal lobe metastasis
5. Spinal cord ependymoma

PREFERRED RESPONSE ▶

Recent Videos

video
UBC- flexible learning program. Neuroanatomy specific, excellent use of specime...
7/31/2014
225 views
5

Evidence & References Show References




Topic Comments

Subscribe status: