New Quiz 03 Jan Welcome to your Neurophysiology Name Email 1. [Technical considerations for intraoperative monitoring (IOM) of the 8th nerve using brainstem auditory evoked potential (BAEP) include all of the following except] If Wave I is indistinct, repositioning of the ipsilateral earlobe electrode is helpful Masking of the contralateral ear with white noise is not necessary Shorter epoch length of less than 10 ms is recommended for averaging the signals Stimulation with alternating click polarities is recommended None . 2. [All of the following characteristics are true about 14- and 6-Hz positive bursts except] They are most common in young adults They can be seen concurrently with 6-Hz spike-wave discharges The bursts last less than 2 seconds They tend to be maximal in the posterior–temporal regions None . 3. [All of the following statements about common mode signals are true except] Common mode signals are dissimilar potentials at different electrode sites that should be ideally rejected Amplifiers are designed to preferentially block common mode signals and to pass the differential-mode signals Unequal impedances between electrodes can affect common mode signals It is recommended that the common mode signals be rejected at a ratio of 80 dB None . 4. [A 55-year-old woman presented with progressive weakness over 4 months. Initially, she noticed increasing difficulty with climbing steps and getting up from the floor. She recently noticed difficulty lifting her arms when reaching above her head or brushing her hair. She reports a mild dull ache in her muscles. She does not have any skin rash. On examination, she has moderate proximal weakness in the upper and lower limbs with preserved distal limb strength. Deep tendon reflexes and sensory examination were normal. Cranial nerve examination revealed mild facial weakness.The rest of the neurological examination is normal.Needle EMG obtained from the deltoid in this patient with minimal effort against resistance is shown below. What does it show? (fig)] Decreased recruitment pattern Normal recruitment pattern Early recruitment pattern Hyperexcitable recruitment pattern None Comment . 5. [Which of the following does not increase the EEG impedance?] Interface between the scalp and the electrode The wiring from the electrode to the amplifier Display of the acquired EEG waveform on the computer screen Skull thickness None . 6. [During facial nerve decompression, which of the following EMG findings is consistent with nerve manipulation?] Neurotonic discharges Myotonic discharges Neuromyotonia Fibrillations None . 7. [In which of the following conditions is it NOT appropriate to perform needle EMG after nerve conduction studies are completed?] If motor nerve conduction studies are normal If the patient does not have insurance If the patient requests that needle EMG not be performed If the patient is on anticoagulation medication and his international normalized ratio (INR) is greater than 1.5 None . 8. [Subclinical rhythmic electrographic discharge in adults (SREDA) has all of the following characteristics except] It is typically in the theta frequency range It could present as rhythmic sharply contoured activity with evolution It can last 1–2 minutes It has been correlated with seizures None . 9. [A new Neurology resident in the neuromuscular clinic starts to do a nerve conduction study and notices that when she stimulates the nerve, the resulting waveform has an initial positivity. Which of the following scenarios could explain this finding?] This is a normal response in all motor and sensory nerve conduction studies This is due to a retreating wavefront This is a bipolar digital sensory study This is a motor response with the recording electrode slightly off the stimulated muscle None . 10. [Which of the following EEG findings is seen in Angelman syndrome?] Low-voltage fast activity Background resembling hypsarrhythmia Tremor associated with 10-Hz rhythmic EEG activity Spells of laughter associated with ictal discharge None . 11. [A 43-year-old male, otherwise healthy, was running a 10K marathon when he had awitnessed generalized tonic–clonic seizure. He was able to stand and walk to the carwith minimal support but was noted to be “not himself.” When he arrived to the closestemergency department (ED) 30 miles away, he was still confused. A stat EEG (filter:1–70 Hz), as shown below, was significant for bitemporal independent and bifrontalindependent spike-wave discharges, as well as periodic seizures consistent with nonconvulsive status epilepticus. Considering the clinical scenario and EEG results, which of the following is the most likely etiology for his presentation? (fig)] Herpes simplex virus (HSV) type II Autoimmune disorder Stroke Anoxic brain injury None Comment . 12. [The activity seen at Point 2 was noted to have an amplitude asymmetry with the amplitude being 80–110 μV on the left side and 100–130 μV on the right. Which of the following statements is true about the amplitude of the depicted activity? (fig)] It is always asymmetric, being higher on the left side Amplitude asymmetry of more than 25% between the 2 sides is considered abnormal It tends to diminish with age It can be increased by doing simple math None Comment . 13. [While performing a nerve conduction study, the neurology resident notices that there is an initial positive deflection on a motor nerve study. He would like to repeat the study to eliminate the initial positive deflection. Which of the following is the best suggestion for him?] Move the G1 electrode to the belly of the recording muscle Move the G2 electrode to increase the distance between the G1 and G2 electrodes Move the stimulating electrode to increase the distance between the stimulating and G1 electrode It is common to have an initial positive deflection in motor studies, so there is no need to repeat the study None . 14. [All of the following statements regarding sleep stages are true except] N1 (Stage I) is characterized by the presence of vertex sharp waves N2 (Stage II) is identified by the presence of K-complexes N3 (Stages III and IV) is marked by a predominance of delta waves REM is characterized by low-voltage theta background None . 15. [What is the best interpretation of the posterior activity seen on the following EEG (filter 1–70 Hz; sensitivity 15 μV/mm; solid vertical lines are 1 second apart) of a 4-year-old boy? (fig)] Posterior slow waves of youth Lambda waves Occipital spike-wave discharge Normal posterior dominant rhythm (PDR) None Comment . 16. [Which of the following does not facilitate a faster conduction velocity?] Larger nerve cross section Longer nerve length Low transmembrane capacitance High transmembrane resistance None . 17. [The following figure shows myogenic motor evoked potentials (mMEPs) from a patientundergoing abdominal aortic aneurysm repair. The top, middle, and bottom panels represent recordings obtained from the left APB, left quadriceps, and left tibialis anterior, respectively. Within each panel, the traces from bottom to top represent 2 minutes before, 2 minutes after, 8 minutes after, and 22 minutes after aortic cross-clamping, respectively. Which of the following statements best describes the findings shown in the figure? (fig)] Both the upper and lower limbs are significantly affected by aortic cross-clamping The upper limb is spared and the flat potentials in the lower limb are artifacts Changes in lower limb potentials represent transient spinal cord ischemia corrected by an increase in mean arterial pressure Above mMEPs are uninterpretable without simultaneous somatosensory evoked potentials (SSEPs) None Comment . 18. [A 45-year-old man with suspected myasthenia gravis had a 3-Hz repetitive stimulation (slow repetitive stimulation) of the left ulnar nerve with abductor digiti minimi (ADM) recording, which was normal. The next most appropriate step for evaluation of neuromuscular junction dysfunction would include] Use a higher rate of stimulation such as 20 or 50 Hz Make sure the limb is not cold, and warm the limb by 3–4°C if needed Administer pyridostigmine and repeat the test Use a higher amplifier gain during the study None . 19. [A 48-year-old male with a history of seizures has an EEG as shown below. During therecording, the patient is noted to be drowsy by the technologist. What is the best interpretation of his EEG (filter: 1–70 Hz)? (fig)] Psychomotor seizures Mild encephalopathy Temporal lobe seizures No known disease process None Comment . 20. [In terms of neuropsychiatric effects, repetitive transcranial magnetic stimulation (rTMS)] Does not alter mood in nondepressed subjects Worsens mood in depressed patients Improves mania Improves or worsens neuropsychological function None . 21. [What is the posterior activity seen in the following EEG (filter: 1–70 Hz; sensitivity: 7μV/mm; vertical lines are 1 second apart) in a 48-year-old woman with a history ofseizures since childhood? (fig)] Lambda waves Positive occipital sharp transients of sleep (POSTS) Spike-wave discharges Posterior slow waves of youth None Comment . 22. [All of the following statements about the amplifier are true except] Its gain is given by the ratio Vout/Vin of the signal Its gain is commonly expressed in decibels Its dynamic range is the voltage range over which it behaves linearly Its gain is directly proportional to sensitivity None . 23. [In the figure below, what is the firing rate of the most prominent motor unit potential? (fig)] 20 Hz 5 Hz 50 Hz 15 Hz None Comment . 24. [A 50-year-old male had intractable back pain and the diagnostic workup was significant for L3–L5 disc bulges. He underwent surgical decompression with intraoperative monitoring (IOM). All the baseline potentials were within normal limits. During the procedure, the N34 and P37/38 potentials disappeared with preservation of the N22 potential. What is the most appropriate localization?] Peripheral nerve Cauda equina Lumbar anterior horn cells Cortex None . 25. [Decreased limb temperature may cause the following electrodiagnostic changes on motor nerve conduction studies:] Increased motor amplitudes Prolonged distal latencies Slowed nerve conduction velocities All of the above None .
