Kaplan questions Flashcards
What is severe retinopathy of prematurity? What are the clinical manifestations? What are the risk factors?
It is an excessive proliferation of vessels in the inner layer of the retina. Manifests as a white pupillary reflex (also found in retinoblastoma and cataracts) Risk factors are prematurity and intensive oxygen therapy
What disease is characterized by accumulation of ganglioside in the retina with foveal sparing?
Tay-Sachs disease. This accumulation and sparing gives rise to the “cherry red” spot that characterized Tay-Sachs. The “cherry red” spot is also characteristic of Niemann Pick disease. The way to tell them apart is that Niemann Pick presents with hepatosplenomegaly and Tay-Sachs does not.
What effect does the mumps virus have on a fetuses brain?
Mumps causes aqueductal stenosis resulting in a noncommunicating hydrocephalus with enlarged 3rd and lateral ventricles, but normal sized 4th ventricles
During CNS development, three primary structures develop into five secondary structures. What are the names of those structures? What do those five secondary structures develop into?
Telencephalon - basal ganglia, cerebral hemispheres, lateral ventricles, Diencephalon - thalamus, pineal gland, hypothalamus, retina, third ventricle Mesencephalon - midbrain and cerebral aqueduct of Sylvius Metencephalon - pons, cerebellum and part of the fourth ventricle Myelencephalon - medulla and part of the fourth ventricle
A stroke in what artery would be most likely to lead to Broca’s aphasia?
Since Broca and Wernicke’s area are in the language dominant hemisphere, which is usually the left hemisphere, a stroke in the left middle cerebral artery would lead to these conditions. A stroke in any artery in the right hemisphere would not cause these conditions.
What are the differences between Broca’s aphasia and Wernicke’s aphasia?
Broca’s aphasia - slow, nonfluent speech with difficulty finding words. Comprehension of language is normal so patients are able to follow vocal and written commands. Patients are often aware of their deficit and very frustrated.
Wernicke’s aphasia - speech is nonsensical but fluent and the patient lacks awareness of their syndrome.
What are the clinical manifestations of rabies? What are the histological characteristics?
Clinical manifestations: extraordinary excitability, headache, difficulty swallowing, convulsions and coma
Histological char/: negri bodies - elongated intracytoplasmic inclusions in neurons of the purkinje cells of the cerebellum and hippocampus
An aneurysm of the superior cerebellar artery, the basilar artery or the posterior cerebral artery could compress what nerve?
The oculomotor nerve because it exits the midbrain at the interpeduncular fossa and runs inbetween these arteries
What are the signs and symptoms of acute angle closure glaucoma? What is the first line treatment for it?
Intense pain, blurred vision, seeing halos around lights, eye is very red, pupil is dilated and not reactive to light, elevated intraocular pressure
Treatment is a carbonic anhydrase inhibitor, acetazolamide, because the CAI reduces bicarbonate production in the ciliary epithelium which decreases aqueous humor production
What are the late stage symptoms of poliovirus?
flaccid paralysis, muscle atrophy, fasciculations, areflexia
What are the main treatments for OCD?
SSRIs - fluoxetine
tricyclic antidepressants - clomipramine
What is the pathway of catecholamine synthesis? What is the rate limiting step?
RDS = tyrosine hydroxylase
What is the most common benign tumor of the CNS? What is the most common malignant tumor originating in the CNS?
benign - meningioma
malignant - glioblastoma multiforme
(most common malignant tumor in the CNS is a metastatic cancer from a non-CNS location)
What are the tests for diagnosis of cryptococcus neoformans?
most sensitive/preferred - latex particle agglutination to detect capsular antigens that are shed in the CSf
Other - India ink stain
What are the site of the most neuronal loss in ALS?
anterior horn of spinal cord (lower motor neurons)
motor cortex of the cerebrum (upper motor neurons)
In the spinal cord, what tracts are present in the dorsal column? lateral column? Lateral horn? ventral column? ventral horn?
dorsal column - fasciculus gracilus and cuneatus (proprioception, vibration and touch)
lateral column - spinothalamic tract (pain and temp), lateral corticospinal tract (motor signals to muscles)
lateral horn - preganglionic sympathetic cell bodies (T1-L2)
ventral column - anterior corticospinal tract (not very important)
ventral horn - lower motor neurons
What is the pharmacologic treatment for ALS? How does the drug work?
Riluzole extends the patient’s lifetime.
ALS is thought to involve excitatory toxicity to neurons from excess glutamate. Riluzole inhibits glutamate release and blocks the glutamate receptor (although not much is known about all this)
Baclofen is used to treat spasticity in ALS but does not extend the patient’s life
Baclofen is a GABA-B agonist
What are all the nerves that provide sensation to the ear? Stimulating which one of them can cause gagging or fainting?
Auricular branch of the Vagus nerve - posterior half of the external ear canal (can cause gagging or fainting because the vagus also mediates the gag and baroreceptor reflex)
Auriculotemporal nerve (branch off mandibular portion of the trigeminal) - anterior half of the external ear canal
Greater auricular - lower part of the auricle
lesser occipital nerve - upper part of the auricle
What are the two higher-order visual processing pathways that determine “what” the object is and “where” the object is?
“What” - temporo-occipital association cortex
“Where” - parietal-occipital association cortex
What develops from the first branchial groove? first branchial pouch? first branchial membrane?
1st branchial groove - external auditory meatus
1st branchial membrane - tympanic membrane
1st branchial pouch - middle ear cavity
What areas of the brainstem does medial medullary syndrome effect? What are the clinical findings? Occlusion of which blood vessel causes medial medullary syndrome?
medial lemniscus - loss of tactile and vibration and proprioception on the contralateral side
hypoglossal nerve nucleus - dysarthria and tongue protrusion to the ipsilateral side
corticospinal tract - contralateral hemiparesis (one-sided body weakness)
Occlusion of the anterior spinal artery can cause medial medullary syndrome
What are the differences between Chari I and Chiari II?
What is the difference between Wernicke’s encephalopathy and Korsakoff syndrome?
