Nokea
The following methods can be used to test solely the rod ERG:
- A. a rapidly flickering light
- B. red light stimulus
- C. low-density blue light in dark adapted eye
- D. focal ERG
Correct Answer: C
Rationale: Low-density blue light in a dark-adapted eye selectively stimulates rods, isolating the rod ERG. Flickering light and red light stimulate cones, and focal ERG is not specific to rods.
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A patient has unilateral facial paralysis and is unable to close his or her right eye. He or she is diagnosed with Bell's palsy. He or she asks the physician if there is any special care required for his or her eye. What is the best response?
- A. No, since the symptoms will go away in a few weeks.
- B. Wear sunglasses.
- C. Increase fluid intake to prevent dryness of the eye.
- D. Yes, you will need to instill artificial teardrops and use an eye patch.
Correct Answer: D
Rationale: Protecting the eye from dryness and injury is essential when the eyelid cannot close properly.
During the first 12 hours of hospitalization you notice that the patient's temperature, pulse, and respiration are showing a steady rise. Petechiae are developing on her chest and she is becoming confused. After notifying the physician, what is the highest priority of care?
- A. Assess for further signs of infection
- B. Continue close monitoring of vital signs and mental status
- C. Encourage fluids and reality orientation measures
- D. Increase ventilation by use of blow bottles
Correct Answer: B
Rationale: Close monitoring helps track progression and manage complications early.
A previously healthy 68-year-old male presents with progressive muscle weakness in his right hand, swallowing difficulty and difficulty with walking. He believes these symptoms occurred "out of the blue" and have worsened over the last 2-3 months. His temperature is 98.6 deg F (37 deg C), blood pressure 145/86 mmHg, pulse is 80/min, and respirations are 17/min. Neurologic examination is significant for mild dysarthria. He has atrophy of the thenar muscles of the right hand and forearm, and 2/5 strength on wrist extension and flexion, as well as 3/5 power in intrinsic hand muscles on right. He has some fasciculations in his right thigh, and mild (4+/5) weakness of hip flexors bilaterally. Tone is increased in both legs. Sensory examination is intact. 3+ patellar reflexes are noted on the left lower extremity. On gait testing, the patient has poor balance, and spastic gait. Which of the following is the most likely diagnosis?
- A. Guillain-Barre syndrome
- B. Amyotrophic lateral sclerosis
- C. Myasthenia gravis
- D. Multiple sclerosis
Correct Answer: B
Rationale: The patient's presentation of progressive muscle weakness, atrophy, fasciculations, and spasticity with hyperreflexia is classic for amyotrophic lateral sclerosis (ALS). ALS involves both upper and lower motor neuron degeneration, leading to a combination of weakness, atrophy, and spasticity. The absence of sensory deficits and the presence of bulbar symptoms (dysarthria, swallowing difficulty) further support this diagnosis. Guillain-Barre syndrome typically presents with ascending paralysis and areflexia, while myasthenia gravis is characterized by fatigable weakness without atrophy or fasciculations. Multiple sclerosis and dermatomyositis do not fit the clinical picture.
Which statements describe neurosyphilis (select one that doesn't apply)?
- A. Occurs 10 to 20 years after bacterial infection
- B. Infection can affect any part of the nervous system
- C. Descending paralysis with cranial nerve involvement
- D. Degenerative changes in the spinal cord and brainstem
Correct Answer: C
Rationale: Neurosyphilis typically presents with degenerative changes in the CNS and can affect various parts of the nervous system.
Mr. Jay is receiving levodopa (L-dopa) to control symptoms of Parkinson disease. Which of the following indicates that he is taking his medication properly?
- A. Anorexia, nausea, and vomiting
- B. Transient hypertension
- C. Constipation
- D. Rapid reduction of rigidity
Correct Answer: D
Rationale: Levodopa effectively reduces rigidity when taken correctly.