New Quiz 03 Jan Welcome to your Neurophysiology Name Email 1. [Which of the following statements best describes the clinical significance of interictal epileptiform discharges (IEDs)?] About 66% of patients with epilepsy show IEDs on the first routine EEG IEDs may not be seen in certain forms of temporal lobe epilepsy on scalp recordings Frequency of IEDs correlates roughly with seizure frequency Hyperventilation (HV) activates generalized IEDs but not focal IEDs None . 2. [Giant somatosensory evoked potential (SSEP) can be seen in all of the following conditions except] Lafora body disease Conditions causing focal motor seizures Juvenile myoclonic epilepsy Hemispheric hemorrhagic stroke None . 3. [Needle EMG in a patient with severe deltoid weakness revealed the following motor unit firing pattern on full activation. What does this finding suggest? (fig 3)] An underlying myopathy An underlying neuromuscular junction dysfunction An underlying neurogenic process This is a normal interference pattern None Comment . 4. [A 50-year-old presents with a 25-year history of bilateral ptosis and double vision. In addition, she has a history of cardiac arrhythmia for which she eventually needed a cardiac pacemaker. On examination, she has bilateral ptosis, limitation of the extraocular movement, and mild proximal weakness. Which of the following findings is likely to be seen on electrodiagnostic testing?] Greater than 10% decrement on slow repetitive stimulation Greater than 100% on increment on fast repetitive stimulation Short duration motor unit potentials on needle EMG Long duration motor unit potentials on needle EMG None . 5. [Acceptable methods for measuring the peak waveform amplitude of the somatosensory evoked potentials (SSEPs) during intraoperative monitoring (IOM) include all of the following except] With respect to the following peak of opposite polarity With respect to the preceding peak of opposite polarity With respect to the baseline level of the waveform preceding the peak With respect to the baseline level of the waveform following the peak None . 6. [A 35-year-old man had extensive injuries in a motor vehicle accident. A few weeks after discharge from the intensive care unit, while underlying rehabilitative therapy, he was noted to have significant weakness in the right upper limb. Findings on needle EMG are shown in the table below. What is the best localization based on these findings? (fig )] Lateral cord Medial cord Posterior cord Lower trunk None Comment . 7. [A 27” computer screen has a resolution of 1920 (horizontal) by 1080 (vertical) pixels with vertical borders of 250 pixels each. An EEG sampled at 1000 Hz is displayed at 15 seconds per page. How many pixels per inch (PPI) are present on the computer screen?] 40 63.1 71.1 81.6 None . 8. [A patient is referred to the neuromuscular clinic for evaluation of a brachial plexopathy. On examination, he was noted to have weakness in the deltoid and triceps; however, the pronator teres muscle and biceps brachii were strong. Presuming that the pathology is in the brachial plexus, these findings are best localizable to which of the following structures?] Medial cord Lateral cord Posterior cord C5–C6 roots None . 9. [Which of the following is the most sensitive test to detect myasthenia gravis (MG)?] Acetylcholine receptor (AChR) antibody titer Repetitive stimulation of facial or spinal accessory nerves Single fiber EMG (SFEMG) of the distal muscle in upper limbs SFEMG of frontalis None . 10. [All of the following statements regarding sleep spindles in infants are true except] They are clearly seen by age 3 months They become synchronous by age 1 year Early on they typically occur in runs lasting seconds They are comb-shaped rather than sinusoidal None . 11. [Which of the following statements is true about electrical shock?] A current of 100 mA or higher applied to the skin can cause ventricular fibrillation in a patient Using 3-hole electrical receptacles eliminates risk of electrical shock to the patient Human susceptibility to electrical shock is maximal at 70 Hz Indwelling catheters do not pose additional risk for electrical shock None . 12. [All of the following statements regarding EEG findings in coma are true except] Generalized burst suppression is invariably associated with poor prognosis regardless of etiology Diffuse monomorphic nonreactive alpha activity can be associated with brainstem lesions or hypoxic-ischemic injury Normal sleep features such as spindles may be seen with cyclic variability A pattern of low-voltage irregular (LVI) activity alternating with high-voltage slowing may be seen in patients with Cheyne–Stokes breathing None . 13. [Alexander disease is likely to be associated with which of the following EEG findings?] Bifrontal slowing Generalized periodic discharges (GPDs) Temporal spikes Burst suppression None . 14. [Ictal patterns in generalized seizures can consist of all of the following except] A 10 Hz spike-and-wave discharge at the onset of a generalized tonic–clonic seizure An electrodecremental pattern during a tonic seizure A 2 Hz spike-and-wave discharge during a staring spell An electrodecremental pattern followed by a high-voltage slow wave during an infantile spasm None . 15. [Which of the following is false regarding myelinated nerves?] Sodium channels and potassium channels are not evenly distributed in myelinated nerves Increased potassium conductance leads to repolarization in myelinated nerves Myelin reduces membrane capacitance and increases transmembrane resistance The junction of Schwann cells is called node of Ranvier None . 16. [Calculation of the negative peak duration and area on the proximal and distal compound muscle action potential (CMAP) are most useful in assessing which of the following electrodiagnostic measures on motor nerve conduction studies?] Conduction velocity Latency Temporal dispersion Stimulus intensity and duration None . 17. [All of the following statements regarding the sleep stages are true except] Stage N1 is characterized by increased theta frequencies Stage N2 is characterized by fronto-central sleep spindles Stage N3 is characterized by delta activity occupying at least 10% of the epoch REM sleep is characterized by eye movements in the setting of atonia None . 18. [Which of the following disorders is considered to be present or worsen during REM sleep?] Sleepwalking Epileptic seizures Obstructive sleep apnea Periodic limb movement disorder None . 19. [An obese 30-year-old male with excessive daytime sleepiness was evaluated. An overnight polysomnogram (PSG) showed sleep-onset latency of 20 minutes, sleep efficiency of 90%, periodic limb movement of sleep (PLMS) index of 10, and an apnea hypopnea index (AHI) of 4. A multiple sleep latency test (MSLT) performed the following morning was not diagnostic for narcolepsy. What is the likely cause of his excessive daytime sleepiness?] Apnea Periodic limb movements of sleep Respiratory effort-related arousals (RERAs) Insomnia None . 20. [Classify the following pattern using the American Clinical Neurophysiology Society’sestablished standardized critical care EEG terminology. (fig)] SI-GRDA LSW BIRDA SI-GSW None Comment . 21. [The following fast Fourier transform (FFT) spectrograms from a 50-year-old male show0–20 Hz activity from the left hemisphere (top panel) and right hemisphere (bottompanel); the color bar indicates the power, black being the lowest and white being thehighest. All of the following statements are correct interpretations at the time markerindicated by the vertical blue line except (fig)] There is a symmetric posterior dominant rhythm The left hemisphere has more power in the alpha and beta frequencies than the right hemisphere There is continuous high-amplitude delta slowing over the right hemisphere There is continuous delta and theta activity over the left hemisphere None Comment . 22. [In evaluating a spinal cord lesion with somatosensory evoked potential (SSEP)] SSEP has no prognostic value regarding sensory recovery compared to clinical examination after acute spinal cord injury SSEP has no value in evaluation of cervical intramedullary tumors since SSEP abnormalities are always accompanied by clinical symptoms Prolonged central conduction time (CCT) with normal potentials suggests extramedullary tumor rather than an intramedullary tumor Cervical syrinx is most commonly associated with absence of N13, P14, and N20 potentials None . 23. [A 19-year-old man presents with difficulty walking for a few years and frequent falls.His peroneal nerve conduction study is shown below. Which of the following tests ismost likely to be diagnostic in this patient? (fig)] Mitofusin (MFN) mutation Peripheral myelin protein (PMP) mutation analysis Very long-chain fatty acids Spinal fluid analysis None Comment . 24. [Which of the following factors may introduce artifacts in the repetitive nerve stimulation study with recording from the abductor pollicis brevis (APB) muscle compared to recording from the abductor digiti minimi (ADM) muscle?] Simultaneous ulnar nerve stimulation at the wrist Movement of recording electrode Cold thumb temperature 60 Hz artifact, which is more likely in distal muscles None . 25. [Which of the following differences between Landau–Kleffner syndrome (LKS) and continuous spike waves of sleep (CSWS) is true?] The discharges in LKS are more bitemporal and/or biparietal vs more diffuse in CSWS There is language regression in CSWS vs a global behavioral regression in LKS Epileptiform activity in LKS gets activated in REM sleep vs in NREM sleep in CSWS Carbamazepine may help in CSWS vs steroids in LKS None .
