Question 1

A 23-year-old female begins having problems with tiredness, weakness, and visual changes. Her diagnosis is multiple sclerosis (MS). The pathogenic model of multiple sclerosis includes:

Accepted Answer

The pathogenic model of multiple sclerosis involves demyelination of nerve fibers in the central nervous system. This leads to problems with nerve conduction and can result in symptoms such as tiredness, weakness, and visual changes. The other options do not accurately describe the pathogenesis of MS.

Question 2

Myasthenia gravis results from:

Accepted Answer

Myasthenia gravis is an autoimmune disorder where the body's immune system attacks the receptors on the neuromuscular junction, leading to muscle weakness and fatigue.

Question 3

A 30-year-old white male recently suffered a cerebrovascular accident. Which of the following is the most likely factor that contributed to his stroke?

Accepted Answer

Diabetes is a significant risk factor for cerebrovascular disease, particularly stroke. Age, gender, and race can all impact stroke risk, but diabetes is a more direct contributor to cerebrovascular accidents.

Question 4

A 15-month-old child from Pennsylvania was brought to the ER for fever, seizure activity, cranial palsies, and paralysis. Which of the following is the most likely cause?

Accepted Answer

Eastern equine encephalitis is the most likely cause because it is the most common cause of encephalitis in the United States.

Question 5

A 65-year-old male suffers a subarachnoid hemorrhage secondary to uncontrolled hypertension. He appears drowsy and confused with pronounced focal neurologic deficits. This condition is a grade:

Accepted Answer

The patient's presentation with focal neurologic deficits and altered mental status indicate a severe subarachnoid hemorrhage, which corresponds to a grade III on the Hunt and Hess grading system. This scoring system is used to assess the severity of subarachnoid hemorrhages, with lower grades indicating milder symptoms and better outcomes, and higher grades indicating more severe symptoms and worse outcomes. Grades I and II typically present with mild or no neurologic deficits, while Grade IV and V present with more profound neurologic deficits, coma, and/or death.

Question 6

One risk factor for thrombotic stroke is:

Accepted Answer

Dehydration can cause the blood to thicken, increasing the risk of blood clots and potentially leading to thrombotic stroke. Hyperthyroidism can increase the risk of atrial fibrillation, which can lead to stroke, but this is not considered a direct risk factor for thrombotic stroke. Fat embolus is a risk for ischemic stroke but not specifically for thrombotic stroke. Anemia can increase the risk of hemorrhagic stroke, but it is not considered a risk factor for thrombotic stroke.

Question 7

A cause of hydrocephalus in subarachnoid hemorrhage is:

Accepted Answer

Subarachnoid hemorrhage can cause scarring of meninges and impair the resorption of cerebrospinal fluid, leading to hydrocephalus. Other options, such as choroid plexus injury, impaired CSF flow through the ventricles, and vasoconstriction related to CO₂ changes in the cerebral circulation, may also contribute to hydrocephalus, but scarring of meninges is more commonly associated with the condition.

Question 8

Classic amyotrophic lateral sclerosis (ALS) presents with:

Accepted Answer

Classic amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease that primarily affects the motor neurons, leading to muscle weakness and atrophy. While some cognitive impairment may occur in later stages of the disease, progressive dementia is not a characteristic feature. Severe paresthesias and autonomic dysfunction are not typically associated with ALS.

Question 9

A 72-year-old male demonstrates left-sided weakness of upper and lower extremities. The symptoms disappear in 24 hours. He most likely experienced a(n):

Accepted Answer

The patient most likely experienced a transient ischemic attack (TIA), which is a temporary disruption of blood flow to the brain that results in stroke-like symptoms. The fact that the symptoms disappeared in 24 hours indicates that it was a TIA and not a stroke-in-evolution, which is a gradual worsening of stroke symptoms over time. An arteriovenous malformation is a congenital abnormality of blood vessels in the brain that can lead to bleeding and stroke, but it does not typically cause transient symptoms. A cerebral hemorrhage is a type of stroke, but it is not temporary and would not resolve in 24 hours.

Question 10

A 60-year-old female with a recent history of head trauma and a long-term history of hypertension presents to the ER for changes in mental status. MRI reveals that she had a hemorrhage stoke. This type of stroke is often caused by:

Accepted Answer

A hemorrhage stroke is caused by bleeding that occurs in the brain, often due to the rupture of an aneurysm (an abnormal bulging in a blood vessel). While rheumatic heart disease and thrombi can contribute to ischemic strokes (caused by blood clots blocking blood flow to the brain), they are not typically associated with hemorrhagic strokes. Hypotension (low blood pressure) can cause ischemic strokes, but not hemorrhagic strokes.

Question 11

The majority of intervertebral disk herniations occur between vertebral levels (cervical, C; thoracic, T; lumbar, L; sacral, S):

Accepted Answer

The majority of intervertebral disk herniations occur between vertebral levels L4 and S1, which is the lower lumbar spine and sacral region. This is because this area bears the most weight and undergoes the most movement and stress.

Question 12

Most causes of encephalitis are:

Accepted Answer

The majority of encephalitis cases are caused by viruses, such as herpes simplex virus, West Nile virus, and enteroviruses. Bacterial and fungal causes of encephalitis are much less common. Toxoid is not a cause of encephalitis.

Question 13

A 25-year-old female presents to her physician complaining of fever, headache, nuchal rigidity, and decreased consciousness. She was previously treated for sinusitis. Which of the following is the most likely diagnosis?

Accepted Answer

The presenting symptoms and history of previous sinusitis indicate a potential bacterial origin for the meningitis, making bacterial meningitis the most likely diagnosis. Aseptic meningitis, nonpurulent meningitis, and fungal meningitis may also present with some of these symptoms, but bacterial meningitis is the most urgent concern and requires immediate treatment.

Question 14

In meningitis, the infection is thought to enter the CNS through the:

Accepted Answer

The answer of In meningitis, the infection is thought to...

Question 15

A 75-year-old male experienced a lacunar stroke. This type of stroke is most often associated with:

Accepted Answer

Lacunar strokes are typically caused by small vessel disease related to hypertension. Emboli, hemorrhages, and aneurysms are less commonly associated with this type of stroke.

Question 16

A major contributing process in cerebrovascular accidents (CVA) is the development of atheromatous plaques in cerebral circulation. These most commonly form:

Accepted Answer

Atheromatous plaques commonly form in cerebral arteries, leading to an increased risk of blockages and ultimately cerebrovascular accidents (strokes).

Question 17

A 48-year-old female presents at the emergency department complaining of an acute severe headache, nausea, photophobia, and nuchal rigidity. These signs and symptoms are probably caused by:

Accepted Answer

The patient's symptoms suggest a subarachnoid hemorrhage, which is bleeding into the space between the brain and the surrounding membrane (the subarachnoid space). This bleeding can cause a sudden, severe headache, along with other symptoms such as nausea, photophobia (sensitivity to light), and nuchal rigidity (stiff neck). Diffuse brain injury and classic concussion typically do not have these specific symptoms, and an epidural hematoma presents with a different set of symptoms (such as a brief loss of consciousness followed by a lucid interval before symptoms return).

Question 18

Of the following groups, who are at highest risk for a cerebrovascular accident?

Accepted Answer

Research has shown that among different racial/ethnic groups, Blacks have the highest risk for cerebrovascular accidents regardless of age, compared to Whites. Additionally, stroke risk doubles each decade after the age of 55, so older individuals are also at higher risk. Therefore, the group at highest risk would be Blacks over 65 years of age.

Question 19

The cause of multiple sclerosis (MS) seems to be an interaction between:

Accepted Answer

Multiple sclerosis is an autoimmune disease, in which the immune system attacks the myelin sheath that covers nerve fibers in the brain and spinal cord. There is also evidence of a genetic component to MS, as there is a higher likelihood of developing the disease if a close family member has it.

Question 20

A 25-year-old male died from a gunshot wound to the heart. Upon autopsy, abnormalities in the media of the arterial wall and degenerative changes were detected. Which of the following most likely accompanied this finding?

Accepted Answer

Saccular aneurysms (berry aneurysms)occur frequently (in approximately 2% of the population)and likely result from congenital abnormalities in the media of the arterial wall and degenerative changes.
Fusiform aneurysms (giant aneurysms)occur as a result of diffuse arteriosclerotic changes and are found most commonly in the basilar arteries or terminal portions of the internal carotid arteries.
Arteriovenous malformation (AVM)is a tangled mass of dilated blood vessels creating abnormal channels between the arterial and venous systems.
Thrombotic stroke would show signs of necrotic tissue,not degenerative changes.

Quiz 15: Alterations of Neurologic Function

A 23-year-old female begins having problems with tiredness, weakness, and visual changes. Her diagnosis is multiple sclerosis (MS) . The pathogenic model of multiple sclerosis includes: