,NSG 550 Exam 4 | Advanced Pathophysiology
Wilkes University | Q & A | 2026/2027 Edition (PDF)
**1. Which of the following is the most appropriate diagnostic study for evaluating a patient with
suspected myasthenia gravis?**
A) Serum cholinesterase level
B) Acetylcholine receptor antibody panel
C) Electroencephalogram (EEG)
D) CT scan of the brain
Correct Answer: Acetylcholine receptor antibody panel
Rationale: Myasthenia gravis is an autoimmune disorder caused by antibodies that block or destroy
acetylcholine receptors at the neuromuscular junction. The acetylcholine receptor (AChR) antibody
panel detects these antibodies and confirms the diagnosis. Serum cholinesterase is used for
organophosphate poisoning, EEG evaluates brain wave activity, and CT brain rules out structural lesions.
**2. A farmer presents with muscle fasciculations, miosis, and excessive salivation after pesticide
exposure. Which laboratory test would best support the diagnosis?**
A) Acetylcholine receptor antibody titer
B) Cholinesterase level
C) Serum electrolytes
D) Complete blood count
Correct Answer: Cholinesterase level
Rationale: Organophosphate poisoning inhibits acetylcholinesterase, leading to accumulation of
acetylcholine and symptoms of muscarinic excess (miosis, salivation, fasciculations). Measuring serum
cholinesterase (pseudocholinesterase or red blood cell cholinesterase) confirms exposure. AChR
antibodies are used for myasthenia gravis, and electrolytes and CBC are non-specific.
,**3. Which electrodiagnostic study is used to evaluate brain wave activity and identify seizures, tumors,
infarcts, and brain death?**
A) Electroencephalogram (EEG)
B) Electromyography (EMG)
C) Nerve conduction studies
D) Caloric testing
Correct Answer: Electroencephalogram (EEG)
Rationale: EEG is a graphical record of brain wave activity obtained through electrodes placed on the
scalp and forehead. It identifies seizures, tumors, infarcts, and brain death. EMG and nerve conduction
studies evaluate peripheral neuromuscular function. Caloric testing evaluates cranial nerve VIII function.
**4. What is the primary purpose of caloric testing in a neurological examination?**
A) To evaluate function of cranial nerve VIII (Vestibulocochlear)
B) To assess for seizures and epileptiform activity
C) To measure intracranial pressure
D) To evaluate optic nerve function
Correct Answer: To evaluate function of cranial nerve VIII (Vestibulocochlear)
Rationale: Caloric testing is an electrodiagnostic test used to evaluate the function of cranial nerve VIII
(Vestibulocochlear). It is part of a complete neuro-otologic examination and assesses vestibular function.
EEG evaluates cortical activity, and caloric testing does not measure intracranial pressure or optic nerve
function.
**5. A 72-year-old male presents with a sudden, severe headache and vomiting. Non-contrast CT head
shows a hyperdense lesion in the basal ganglia. Which of the following is the most likely diagnosis?**
A) Ischemic stroke
B) Subarachnoid hemorrhage
C) Intracerebral hemorrhage
, D) Brain tumor
Correct Answer: Intracerebral hemorrhage
Rationale: A hyperdense (bright) lesion on non-contrast CT in the basal ganglia is characteristic of acute
intracerebral hemorrhage. Hypertension is the most common cause of intracerebral hemorrhage in the
basal ganglia. Ischemic stroke appears as a hypodense area, subarachnoid hemorrhage appears as
hyperdensity in the subarachnoid spaces, and tumors may appear as hypodense or isodense lesions.
**6. Which of the following is the most appropriate initial imaging study for a patient with suspected
acute ischemic stroke within the first 6 hours of symptom onset?**
A) MRI brain with diffusion-weighted imaging (DWI)
B) CT head without contrast
C) CT angiography of the head and neck
D) Carotid Doppler ultrasound
Correct Answer: CT head without contrast
Rationale: Non-contrast CT head is the initial imaging study of choice for suspected acute stroke because
it rapidly excludes hemorrhage, which is a contraindication to thrombolytic therapy. While MRI with
DWI is more sensitive for early ischemia, CT is faster and more widely available in the acute setting. CTA
and Doppler are used for vascular evaluation.
**7. A 65-year-old female presents with acute onset of right-sided weakness and facial droop. Which of
the following diagnostic studies would be most appropriate to evaluate for carotid artery stenosis as a
potential cause?**
A) Carotid Doppler ultrasound
B) CT angiography of the head
C) Magnetic resonance angiography
D) Conventional angiography
Correct Answer: Carotid Doppler ultrasound
Wilkes University | Q & A | 2026/2027 Edition (PDF)
**1. Which of the following is the most appropriate diagnostic study for evaluating a patient with
suspected myasthenia gravis?**
A) Serum cholinesterase level
B) Acetylcholine receptor antibody panel
C) Electroencephalogram (EEG)
D) CT scan of the brain
Correct Answer: Acetylcholine receptor antibody panel
Rationale: Myasthenia gravis is an autoimmune disorder caused by antibodies that block or destroy
acetylcholine receptors at the neuromuscular junction. The acetylcholine receptor (AChR) antibody
panel detects these antibodies and confirms the diagnosis. Serum cholinesterase is used for
organophosphate poisoning, EEG evaluates brain wave activity, and CT brain rules out structural lesions.
**2. A farmer presents with muscle fasciculations, miosis, and excessive salivation after pesticide
exposure. Which laboratory test would best support the diagnosis?**
A) Acetylcholine receptor antibody titer
B) Cholinesterase level
C) Serum electrolytes
D) Complete blood count
Correct Answer: Cholinesterase level
Rationale: Organophosphate poisoning inhibits acetylcholinesterase, leading to accumulation of
acetylcholine and symptoms of muscarinic excess (miosis, salivation, fasciculations). Measuring serum
cholinesterase (pseudocholinesterase or red blood cell cholinesterase) confirms exposure. AChR
antibodies are used for myasthenia gravis, and electrolytes and CBC are non-specific.
,**3. Which electrodiagnostic study is used to evaluate brain wave activity and identify seizures, tumors,
infarcts, and brain death?**
A) Electroencephalogram (EEG)
B) Electromyography (EMG)
C) Nerve conduction studies
D) Caloric testing
Correct Answer: Electroencephalogram (EEG)
Rationale: EEG is a graphical record of brain wave activity obtained through electrodes placed on the
scalp and forehead. It identifies seizures, tumors, infarcts, and brain death. EMG and nerve conduction
studies evaluate peripheral neuromuscular function. Caloric testing evaluates cranial nerve VIII function.
**4. What is the primary purpose of caloric testing in a neurological examination?**
A) To evaluate function of cranial nerve VIII (Vestibulocochlear)
B) To assess for seizures and epileptiform activity
C) To measure intracranial pressure
D) To evaluate optic nerve function
Correct Answer: To evaluate function of cranial nerve VIII (Vestibulocochlear)
Rationale: Caloric testing is an electrodiagnostic test used to evaluate the function of cranial nerve VIII
(Vestibulocochlear). It is part of a complete neuro-otologic examination and assesses vestibular function.
EEG evaluates cortical activity, and caloric testing does not measure intracranial pressure or optic nerve
function.
**5. A 72-year-old male presents with a sudden, severe headache and vomiting. Non-contrast CT head
shows a hyperdense lesion in the basal ganglia. Which of the following is the most likely diagnosis?**
A) Ischemic stroke
B) Subarachnoid hemorrhage
C) Intracerebral hemorrhage
, D) Brain tumor
Correct Answer: Intracerebral hemorrhage
Rationale: A hyperdense (bright) lesion on non-contrast CT in the basal ganglia is characteristic of acute
intracerebral hemorrhage. Hypertension is the most common cause of intracerebral hemorrhage in the
basal ganglia. Ischemic stroke appears as a hypodense area, subarachnoid hemorrhage appears as
hyperdensity in the subarachnoid spaces, and tumors may appear as hypodense or isodense lesions.
**6. Which of the following is the most appropriate initial imaging study for a patient with suspected
acute ischemic stroke within the first 6 hours of symptom onset?**
A) MRI brain with diffusion-weighted imaging (DWI)
B) CT head without contrast
C) CT angiography of the head and neck
D) Carotid Doppler ultrasound
Correct Answer: CT head without contrast
Rationale: Non-contrast CT head is the initial imaging study of choice for suspected acute stroke because
it rapidly excludes hemorrhage, which is a contraindication to thrombolytic therapy. While MRI with
DWI is more sensitive for early ischemia, CT is faster and more widely available in the acute setting. CTA
and Doppler are used for vascular evaluation.
**7. A 65-year-old female presents with acute onset of right-sided weakness and facial droop. Which of
the following diagnostic studies would be most appropriate to evaluate for carotid artery stenosis as a
potential cause?**
A) Carotid Doppler ultrasound
B) CT angiography of the head
C) Magnetic resonance angiography
D) Conventional angiography
Correct Answer: Carotid Doppler ultrasound
