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
QUESTIONS 1 of 3 1 2 3 Previous Next Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK (M1.NE.14.77) 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? QID: 106877 FIGURES: A Type & Select Correct Answer 1 Frontal lobe cavernoma 17% (14/81) 2 Craniopharyngioma 20% (16/81) 3 Pinealoma 51% (41/81) 4 Melanoma with temporal lobe metastasis 4% (3/81) 5 Spinal cord ependymoma 1% (1/81) M 1 Question Complexity D Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 3 Review Tested Concept Review Full Topic (M1.NE.14.11) 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? QID: 101675 Type & Select Correct Answer 1 Medulla oblongata 60% (48/80) 2 Medial geniculate nucleus 2% (2/80) 3 Lateral geniculate nucleus 1% (1/80) 4 Posterior hypothalamus 10% (8/80) 5 Ventral posterolateral nucleus 22% (18/80) M 1 Question Complexity D Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 1 Review Tested Concept Review Full Topic
All Videos (1) Login to View Community Videos Login to View Community Videos Overview of the Brain Stem Neurology - Brainstem D 7/31/2014 115 views 5.0 (6)