Neurology: UWorld Flashcards
(234 cards)
What part of the brain is predominantly affected by Progressive multifocal leukoencephalopathy (PML)?
Cortical white matter
The brainstem and cerebellum can be involved too.
The following findings are consistent with what diagnosis?
- Spontaneous speech: Fluent & voluminous but lacks meaning
- Comprehension: Greatly diminished
- Repetition: Impaired
- Associated features: Right superior visual field defect
Wernicke’s (Receptive) aphasia
Patient’s with Wernickes’s aphasia have difficulty comprehending and following commands but are able to speak fluently. However, their speech tends to be rambling without concrete meaning. Receptive aphasia results from a dominant temporal lobe lesion.
A person’s ability to comprehend emotional gestures can be affected by a brain lesion located where?
Nondominant temporal lobe
These patients can also develop a contralateral homonymous quadrantanopsia due to the inferior optic radiations involvement.
Any patient admitted for Guillain-Barre syndrome should be evaluated frequently with serial measurements of what?
Vital capacity
Vital capacity is the best way to monitor respiratory function and assess for respiratory failure.
The following findings are consistent with what diagnosis?
- Spontaneous speech: Fluent with phonemic errors
- Comprehension: Relatively preserved
- Repetition: Very poor
- Associated features: None
Conduction aphasia
Conductive aphasia results from a dominant temporal lobe lesion (like receptive aphasia). It occurs when the lesion involves the arcuate fasciculus.
Herpes mainly affects which lobe of the brain?
Temporal lobe
Herpes encephalitis accounts for 10-20% of all viral encephalitis, and is the most common cause of fatal sporadic encephalitis in the United States. HSV-1 is the etiological agent in almost all cases beyond the neonatal period. Intravenous acyclovir is the treatment of choice.
What is the management for both cauda equina syndrome and conus medularis syndrome?
- Emergency magnetic resonance imaging
- Intravenous glucocorticoids
- Neursurgical evaluation
Diffuse atrophy of the cerebral cortex is a feature of what disease?
Alzheimer’s disease
What test/study is useful in differentiating conditions like infectious meningitis and multiple sclerosis?
Lumbar puncture
Oligoclonal bands are characteristic of Multiple Sclerosis.
The following characteristics are indicative of which subtype of stroke?
- Risk factors: Uncontrolled hypertension, diabetes
- Fluctuating symptoms - stuttering progression with periods of improvement
Thrombotic (ischemic) stroke
Local in-situ obstruction of an artery occurs.
The following signs/symptoms are characteristic of which diagnosis?
- Severe lower back pain with bilateral radiculopathy
- Saddle anesthesia
- Hyporeflexia
- Profound asymmetric motor weakness
- Bowel and bladder dysfunction.
Cauda equina syndrome
This is contrasted to conus medullaris syndrome which presents with
- Severe back pain with lesser degree of radiculopathy
- Perianal anesthesia
- Hyperreflexia
- Mild bilateral motor weakness
- Bowel and bladder disturbances
What is the study of choice in diagnosing multiple sclerosis?
Magnetic resonance imaging (MRI)
Cerebral and spinal plaques composed of clusters of demyelinated axons appear as hypo/hyperintense lesions on MRI. The lesions involve the white matter of the central nervous system, particularly the periventricular and subpial white matter of the cerebrum (corpus callosum), optic nerves, brain stem, and spinal cord. Lumbar puncture is also recommended to document oligoclonal IgG bands (found in >95% of clinically definite multiple sclerosis patients) in the cerebrospinal fluid to establish the diagnosis.
Tabes dorsalis is a manifestation of what condition?
Neurosyphilis
It is characterized by destruction of the posterior columns leading to loss of proprioception. The patient walks with his/her legs wide apart. The feet are lifted higher than usual, and make a slapping sound when they come in contact with the floor. Romberg’s sign may be positive.
Unilateral eye pain, vision loss, and an associated afferent pupillary defect are characteristic features of what condition?
Optic neuritis
This is commonly associated with multiple sclerosis, but can be seen with other disorders as well.
The following findings are consistent with a lesion to what region?
- Contralateral ataxia
- Hemiparesis of the face, trunk, and limbs (ataxic hemiparesis)
- Variable loss of contralateral tactile and position sense
Medial mid-pontine infarction
Cognitive dysfunction with motor and sensory neurological dysfuntion is characteristic of what condition?
Multi-infarct dementia
This accounts for 15-20% of dementia cases. The associated risk factors are: older age, male sex, black race, cigarette smoking, hypertension, diabetes, and vasculitis. The treatment is generally directed towards the risk factors.
The following findings are consistent with what diagnosis?
- Deep coma and paraplegia that develops within minutes
- Pupils pinpoint and reactive to light
- Decerebrate rigidity
Pontine hemorrhage
This accounts for 5-12% of cases of hypertensive intraparenchymal hemorrhages.
Hemi-sensory loss with severe dysesthesia (unpleasant abnormal sense of touch) of the affected area is typical for what?
A thalamic stroke (Dejerine-Roussy syndrome)
This condition is caused by a stroke involving ventral postero-lateral (VPL) nucleus of the thalamus, which transmits sensory information from the contralateral side of the body.
Corticospinal tract lesions cause what?
Spastic paresis
Unilateral corticospinal lesions may cause hemiplegic gait, where the spastic leg is held extended and internally rotated and walking is accomplished by abducting and advancing the spastic leg.
Fatigable muscle weakness that primarily involves the extraocular and bulbar musculature is most consistent with what condition?
Myasthenia gravis
Myasthenia gravis affects only motor nerves, with preservation of the sensory nerves. The creatine phosphokinase (CPK) is generally normal, which helps to distinguish it from a primary muscle problem. Approximately 15% of patients with myasthenia gravis have a coexisting thymoma, thus screening computed tomography of the chest is generally recommended.
What condition presents as recurrent, acute-onset vertigo that is precipitated by head movement, and has associated symptoms of nystagmus, nausea, and vomiting?
Benign paroxysmal positional vertigo
This occurs when calcium crystals within the inner ear shift position.
What two medications can be given to treat essential tremor in a patient who cannot tolerate propranolol?
- Primidone
- Topiramate
What is the most effective symptomatic therapy for parkinsonism?
Levodopa/Carbidopa
The most common early side effects are hallucinations, dizziness, headache, and agitation. After several years of therapy, involuntary movements are more likely to occur.
Acute exacerbations of multiple sclerosis (MS) are treated with what?
Corticosteroids
Plasmapheresis may enhance the beneficial effect of immunosuppression. Although they have no proven role in the treatment of acut MS exacerbations, beta-interferon or glatiramer acetate can be used used to decrease the frequency of exacerbations in patients with relapsing-remitting or secondary progressive form of MS.