Intraoperative Neuromonitoring: Understanding Evoked Potentials and Electrophysiology, Exams of Public Health

Download Intraoperative Neuromonitoring: Understanding Evoked Potentials and Electrophysiology and more Exams Public Health in PDF only on Docsity! Which of the following temperatures should be annotated as being hypothermic? 1. 34 degrees Celsius 2. 35 degrees Celsius 3. 38 decrees Celsius 4. 40 degrees Celsius - ANSWER--1. 34 degrees Celsius What is the most likely effect of isoflurane at MAC 1.5 on tibialis anterior CMAP amplitude in response to spinal stimulation? 1. Marked increase 2. Marked decrease 3. Minimal decrease 4. Minimal increase - ANSWER--2. Marked decrease It is most important for intraoperative monitoring records to include notions of? 1. Surgical events 2. periodic impedance checks 3. serial changes in hematocrit 4. changes in anesthesia personnel - ANSWER--1. Surgical events Which of the following is a critical surgical event? 1. Drilling of burr hole in skull 2. Decortication of vertebral elements 3. Placing of muscle plug in the internal auditory canal 4. Resecting of tumor fragments during acoustic neuroma resection - ANSWER--4. Resecting of tumor fragments during acoustic neuroma resection Which of the following should be reported to the surgeon? 1. Loss of response 2. Change in time base 3. Switch to backup electrodes 4. increase in stimulus intensity - ANSWER--1. loss of response D waves are recorded from which of the following electrodes? 1. Epidural electrodes over the spinal cord 2. Subdural electrodes over the motor strip 3. Surface electrodes over peripheral nerves 4. Needle electrodes in distal extremity muscles - ANSWER--1. Epidural electrodes over the spinal cord Transcranial motor evoked potentials are best elicited when using? 1. a train of stimuli 2. complete neuromuscular blockade 3. halogenated agents 4. stimulus rates above 20/sec - ANSWER--1. a train of stimuli In Compressed Density Spectral Array, frequency is depicted by? 1. Y-axis 2. X-axis 3. Epoch 4. Data Points - ANSWER--2. X-Axis Transcranial electrical motor evoked potentials are best recorded with which of the following anesthetic regiments? 1. Nitrous oxide 50% + midazolam bolus 2. Isoflurane .5 MAC + midazolam infusion 3. Nitrous oxide 50% + isoflurane <0.5 MAC 4. Propofol + Fentanyl infusion - ANSWER--4. Propofol + Fentanyl infusion During carotid endarterectomies Spectral Edge Frequency is usually set to? 1. 60-67% 2. 70-77% 3. 80-87% 4. 90-97% - ANSWER--4. 90-97% Which of the following anesthetic agent will obliterate the transcranial electric motor evoked potential? 1. Propofol 2. Desflurane 3. Fentanyl 4. Nitrous Oxide - ANSWER--2. Desflurane Which of the following systolic blood pressure is most likely to attenuate the evoked potential? 1. 150 mm/Hg 2. 140 mm/Hg 3. 130 mm/Hg 4. 120 mm/Hg - ANSWER--4. 120 mm/Hg One contraindication for the use of transcranial electrical motor evoked potential is? 1. epilepsy 2. trigeminal neuralgia 3. scoliosis 4. cervical myelopathy - ANSWER--1. epilepsy RADICULOPATHY? 1. Meninges 2. Spinal cord 3. Nerve roots 4. Peripheral Nerves - ANSWER--3. Nerve roots SPONDYLOSIS? When monitoring Brainstem auditory evoked potentials intraoperatively it is recommended to warn the surgeon when an increase of the following occurs? 1. the latency of wave V of less than 1.0 millisecond 2. the latency of wave I of 1 millisecond 3. the latency of wave V of 1.0 or greater 4. the interpeak latency of 1-V of 1.0 or less - ANSWER--3. the latency of wave V of 1.0 or greater The use of intraoperative monitoring during scoliosis surgery may replace the? 1. Hoffman sign 2. Stagnara test 3. Romberg test 4. Babinski sign - ANSWER--2. Stagnara test (wake up test - pt moves feet) HOFFMAN SIGN? - ANSWER---Assess Myelopathy (spinal cord compression) -The test is done by quickly snapping or flicking the patient's middle fingernail. The test is positive for spinal cord compression when the tip of the index finger, ring finger, and/or thumb suddenly flex in response. ROMBERG TEST? - ANSWER---TESTS BALANCE -PROPRIOCEPTION, VESTIBULAR FUNCTION & VISION Upon sudden loss of ipsilateral posterior tibial cortical and subcortical data which of the following should be performed? 1. Calibration 2. Stagnara test 3. Train of four 4. Tetanic stimulation - ANSWER--2. Stagnara test Which of the following is a source of intraoperative physiologic artifacts? 1. Cell saver 2. Blood warmer 3. Electrocardiogram 4. Electrooculogram - ANSWER--3. Electrocardiogram If there is a 60hz interference in all channels when recording preoperative median nerve SSEPs, which of the following electrodes should be adjusted first? 1. CPi 2. EPc 3. Grounding electrode 4. Stimulating electrode - ANSWER--3. Grounding electrodes Which of the following would most affect the ability to record BAEPs? 1. Drill 2. Retractor 3. Coagulator 4. Anesthetic agent - ANSWER--3. Coagulator Evoked potential data is obilterated with? 1. midas rex drilling 2. monopolar cautery 3. C-arm use 4. transcranial dopper use - ANSWER--2. monopolar cautery Which of the following most often causes a temporary threshold shift on the Brainstem auditory evoked potentials during CPA surgery? 1. Drilling 2. bipolar cautery 3. warm irrigation 4. CUSA - ANSWER--1. drilling 1. avoid tissue damage 2. protect equipment form breakdown 3. minimize 60hz interference 4. prevent chassis current leakage - ANSWER--1. avoid tissue damage The pneumatic drill has which of the following effects on BAEP'S? 1. None 2. Prolongs Wave V 3. Increases I-III interpeak latency 4. Increase III-V interpeak latency - ANSWER--2. Prolongs Wave V In posterior fossa craniotomy surgery for a large tumor with unilateral hearing loss, the appropriate modalities to monitor would be: a) Contralateral BAEP, median nerve and facial nerve b) Ipsilateral BAEP and facial nerve c) Facial nerve and contralateral median nerve d) Ipsilateral BAEP - ANSWER--a) Contralateral BAEP, median nerve and facial nerve During middle or posterior fossa surgery, what structure is most at risk? a) Cerebellum b) Brainstem c) Optic Nerve d) Spinal Cord - ANSWER--b) Brainstem In posterior fossa surgery, an increase in the III-V interpeak interval would most likely be due to: a) Traction on the cerebellum b) Compression of the upper midbrain c) Traction on the acoustic nerve d) Fluid in the middle ear - ANSWER--a) traction on the cerebellum What muscle would you monitor for EMG activity for cranial nerve XII? a) Tongue b) Trapezius c) Masseter d) Frontalis - ANSWER--a) tongue If CN VII were transected, you would get: a) Absence of all waves I-V b) Increased I-III latency c) Loss of wave V only d) No changes - ANSWER--d) No changes Loss of BAEP's during drilling of the internal auditory canal is most likely due to: a) Disruption of the blood supply b) Compression of the brainstem c) Transection of the auditory nerve d) Artifact from the drill - ANSWER--d) Artifact from the drill What would be the effect of fluid in the internal auditory canal? a) Increase of the absolute latencies b) Increased wave amplitudes c) Increased I-V latency d) Loss of all waves - ANSWER--a) increase of the absolute latencies The prominent wave for monitoring BAEP's is: a) Wave I d) 75 dB SPL - ANSWER--c) 60 dB SL The peak equivalent SPL of a click should be: a) 500 Hz b) 3000 Hz c) 5000 Hz d) 10,000 Hz - ANSWER--b) 3000 Hz Which of the following potentials will change with click polarity? a) Wave I latency b) I-V interpeak c) Wave V latency d) Wave V amplitude - ANSWER--d) Wave V amplitude The proper filter settings for recording BAEP's are: a) 1-25 to 2500-3000 Hz b) 1-250 Hz c) 500-5000 Hz d) 1-1000 Hz - ANSWER--a) 1-25 to 2500-3000 Hz If unavoidable muscle artifact is present in the BAEP, you can change the filters to: a) 500-1000 Hz b) 100-200 to 1500 Hz c) 10-500 Hz d) 1-1000 Hz - ANSWER--b) 100-200 to 1500 Hz Hearing level (HL) is defined by: a) An individual's hearing threshold b) The average hearing threshold of a normal population c) The absolute sound pressure relative to atmospheric pressure d) A table of clinical values - ANSWER--b) The average hearing threshold of a normal population Sensation level (SL) is defined by: a) An individual's hearing threshold b) The average hearing threshold of a normal population c) The absolute sound pressure relative to atmospheric pressure d) A table of clinical values - ANSWER--a) An individual's hearing threshold In the presence of irreducible artifact, the filters may be set at 100-200 - 1000 Hz for recording intraoperative: a) SSEPS b) EMG c) MEPs d) BAEPs - ANSWER--d) BAEPs Wave V of the BAEP is most affected by: a) Anesthesia below 1 MAC b) Retraction c) Muscle relaxants d) Temperature changes - ANSWER--b) retraction If the latency of Wave III of the BAEP is 4.5 using tube inserts it will be: a) 5.4 using headphones b) The same using headphones c) 3.6 using headphones d) 5.4 using small inserts - ANSWER--c) 3.6 using headphones The filter settings for recording BAEPs intraoperatively should be: a) Has no effect on evoked potential latencies b) Decreases evoked potential latencies c) Has a variable effect on evoked potential latencies d) Increases evoked potential latencies - ANSWER--d) Increases evoked potential latencies Monitoring somatosensory function may fail to recognize changes in: a) Efferent motor pathways in the cord b) Dorsal Column function c) Peripheral Nerve function d) Ascending spinal cord tracts - ANSWER--a) Efferent motor pathways in the cord Cranial Nerves V and VII may be differentiated by: a) Latency in response to stimulation b) Amplitude in response to stimulation c) Morphology, regardless of electrode placement d) None of the above - ANSWER--a) Latency in response to stimulation Electronic devices used to store electrical charge are called: a) Resistors b) Insulators c) Capacitors d) Conductors - ANSWER--c) Capacitors Ohm's Law states: a) E = I x R b) R = I x E c) I = E x R d) E = I/R - ANSWER--a) E = I x R Impedance is defined as: a) The flow of alternating current b) Opposition to the flow of direct current c) Opposition to the flow of alternating current d) Opposition to the change in flow of current - ANSWER--c) Opposition to the flow of alternating current The basic unit for measuring current flow is: a) Coulomb b) Ampere c) Density d) Vold - ANSWER--b) Ampere Electrodes of dissimilar metals should not be used togehter because: a) Electrolyte only works with certain electrodes b) The amplifiers will only accept input form one type of electrode c) Dissimilar electrodes have no resistance d) The materials in different electrodes have different conductive properties - ANSWER--d) The materials in different electrodes have different conductive properties The basic unit of resistance is the: a) Ohm b) Coulomb c) Ampere d) Volt - ANSWER--a) Ohm Which of the following is most attenuated by a low frequency filter of 1 Hz? a) 50 uV rms at 60 Hz b) 60 mV rms at 50 Hz c) 20 uV rms at 60 Hz d) 20 mV rms at 60 Hz - ANSWER--d) 20 mV rms at 60 Hz What is the voltage delivered to a patient if the constant current stimulator is set at 50 mA and the skin resistance is 40 Ohms? (E = I x R) a) 100V b) 1V c) 200V d) 2V - ANSWER--d) 2V For patients showing clamp related EEG changes during CEA, 80% occur within the: a) 10-13 Hz alpha range b) Contralateral Hemisphere c) First minute d) First 10 seconds - ANSWER--c) FIRST MINUTE What is the frequency of a waveform that has a wavelength of 25 ms? a) 1000 Hz b) 1 kHz c) 40 Hz d) 400 Hz - ANSWER--c) 40 Hz (1/.025 = 40 Hz) Given a wavelength of 5.0 ms, what is the minimum sampling rate required to resolve the response with aliasing in it? a) 200 Hz b) 2000 Hz c) 0.0002 Hz d) 500 Hz - ANSWER--c) 0.0002 Hz (5msec=0.005sec=200Hz) Rarefaction clicks create? a) Positive pressure within the auditory canal b) Negative pressure within the auditory canal c) Alternating positive and negative pressure d) None of the above - ANSWER--b) Negative pressure within the auditory canal The generator site for the N9 response during median nerve stimulation is: a) Decussation of the posterior columns in the pyramidal region b) Superior olivary complex c) Near-Field conduction volley d) Sensory cortex - ANSWER--c) Near-Field conduction volley Which of the following drugs will have no effect on cortical SEPs? a) Vecuronium b) Narcotics c) Pentothal c) Isoflurane - ANSWER--a) Vecuronium Which of the following tibial nerve responses is NOT a near-field response? a) N45 b) Popilteal fossa response c) N30 d) P37 - ANSWER--c) N30 It is REQUIRED that the neurotechnologist be able to communicate effectively with: a) the circulating nurse d) Brainstem compression - ANSWER--c) Opthalmaplegia Which of the following is the most appropriate time base for CN VII CMAP? a) 1 ms b) 20 ms c) 12 ms d) 5 ms - ANSWER--c) 12 ms In order to monitor the recurrent laryngeal nerve, the recording electrodes are placed in the: a) Trapezius muscle b) Soft palate c) Tongue d) False Vocal Cords - ANSWER--d) False Vocal Cords Monitoring procedures during carotid endarterectomy include: a) Monitoring of both hemispheres b) Cessation of monitoring following clamp removal c) Monitoring from the compromised hemisphere only d) Recording a full minute of EEG baseline - ANSWER--d) Recording a full minute of EEG baseline Which of the following is the most appropriate time base for an auditory evoked potential? a) 1 ms b) 6 ms c) 12 ms d) 20 ms - ANSWER--c) 12 ms Which of the following anatomic structures is NOT monitored by tibial nerve SSEP? a) Dorsal spinal columns b) Tibial Nerve c) Somatosensory portion of the brain in the midline region d) L4 nerve root - ANSWER--d) L4 nerve root Which of the following preoperative conditions does not affect the SEP of the tibial nerve with stimulation at the ankle? a) Cervical myelopathy b) Severe diabetes c) Paraplegia d) Cervical radiculopathy - ANSWER--d) Cervical radiculopathy Differential amplifiers should be rated with a common mode rejection ratio of at least: a) 1000:1 b) 60 dB c) 10,000:1 d) 1,000,000: 1 - ANSWER--c) 10,000:1 "Hearing Level" (HL) is defined as the: a) average threshold intensity of normally hearing young adults b) Intensity of long duration sound that has the same amplitude as the peak SP of a short duration sound c) Lowest intensity that an average eardurm can hear d) Inverse of the sound pressure level - ANSWER--a) average threshold intensity of normally hearing young adults Brain activity recorded directly from the cortex (ECoG) is very high in amplitude and usually requires sensitivities in the range of: a) 10-50 mV/mm d) Power and frequency vs. time - ANSWER--d) Power and frequency vs. time What separates the sensory and motor cortical strips? a) Falx cerbri b) Sylvian fissure c) Central sulcus d) Frontal sulcus - ANSWER--c) Central sulcus Which of the following is NOT a safety concern regarding TCMEPs? a) Tongue lacerations b) History of seizure disorders c) History of cerebral palsy d) Pacemaker - ANSWER--c) History of cerebral palsy Which of the following drugs will increase the amplitude of cortical SSEPs? a) Diprovan b) Etomidate c) Pavulon d) Isoflurane - ANSWER--b) Etomidate Which of the following is a reason why false negatives can occur? a) Documentation is incomplete b) Changes were seen and communicated to the surgeon but no postoperative deficits were noted c) Physiological damage occurred d) The lesion occurs in a structure not involved in the pathways being monitored - ANSWER--d) The lesion occurs in a structure not involved in the pathways being monitored Spinal Cord Ischemia during aortic surgery is best detected by changes in the: a) Posterior tibial nerve SSEP b) Median nerve SSEP c) Tibial Nerve compound action potential d) Lumbar potential - ANSWER--a) Posterior tibial nerve SSEP Wave III of the BAEP is generated in the: a) Distal portion of the auditory nerve b) Cochlea c) Masseter d) Lower Brainstem - ANSWER--d) Lower brainstem When monitoring the facial nerve, wire electrodes should be placed in the: a) Masseter b) Contralateral nasalis c) Orbicularis oculi and orbicularis oris d) Frontalis and masseter - ANSWER--c) Orbicularis oculi and orbicularis oris During microvascular decompression to relieve hemifacial spasm: a) CN VI should be monitored b) CN V should be monitored c) CN VII should be monitored d) CN VIII should be monitored - ANSWER--c) CN VII should be monitored A bipolar stimulator allows the surgeon to: a) Be more specific in identifying structures b) Stimulate larger areas c) Use a higher stimulus intensity d) Use a shorter stimulus duration - ANSWER--a) Be more specific in identifying structures How might you best decrease stimulus artifact while recording BAEPs intraoperatively? a) Use rarefaction clicks b) Use tone pips c) Use condensation clicks d) Use clicks of alternating polarity - ANSWER--d) Use clicks of alternating polarity A patient present for an L1 burst fracture repair. What is the most appropriate monitoring protocol? a) Tibial and auditory nerves b) Median and ulnar nerves c) Tibial and median nerves d) Tibial and peroneal nerves - ANSWER--c) Tibial and median nerves At the stage of surgical anesthesia, propofol affects the BAEPs by: a) Dramatically increasing all absolute latencies b) Decreasing all waveform amplitudes c) Aboloshing all waveforms d) Causing minimal changes - ANSWER--d) Causing minimal changes A wave III to V interpeak latency increase can be indictive of a lesion in: a) the distal portion of cranial nerve VIII b) between the distal portion of the nerve and the pons c) Between the pons and the upper brainstem d) The middle ear - ANSWER--c) Between the pons and the upper brainstem Efferent pathways: a) Conduct impulses from the CNS to the peripheral nerves b) Are motor pathways c) are sensory pathways d) Both A and B - ANSWER--d) Both A and B If a sound intensity is increased from 20dB to 40dB, then the sound has increased by a factor of: a) 2 b) 10 c) 20 d) 100 - ANSWER--a) 2 When testing BAEPs, you get a Wave I on your contralateral montage. What should you do? a) Increase click intensity b) Check ear phones for proper side stimulation c) Change polarity of click to condensation d) Don't do anything - ANSWER--b) Check ear phones for proper side stimulation Which of the following would most likely result in an increased I-III interval? a) Decreased click intensity b) Acoustic Schwannoma c) Cochlear lesion d) Petrous osteoma - ANSWER--c) Cochelar lesion What montage will help you discern waves IV and V in BAEP? a) Ipsi ear - contra ear b) Cz - contra ear c) Ipsi ear - Fz d) Cz - Fz - ANSWER--b) Cz - Contra ear a) pedicles b) intervertebral discs c) supraspinous ligaments d) spinal nerves - ANSWER--b) intervertebral discs Which of the following upper extremity somatosensory responses is considered a "stationary potential"? a) N20 b) N13 c) P14 d) N18 - ANSWER--b) N13 The initial waveform recorded of a near-field potential is? a) always obscured by stimulus artifact b) negative due to depolarization of membrane potentials positive due to electrotonic depolarization c) of the membrane under the recording electrode d) of very low amplitude due to the significant distance between the generator and recording electrode - ANSWER--b) negative due to depolarization of membrane potentials positive due to electrotonic depolarization Nerves of the body, such as the ulnar, median, and femoral, are formed from the: a) white matter of the spinal cord b) dorsal and ventral rami c) cervical spinal cord d) ventral ganglion - ANSWER--b) dorsal and ventral rami On the SSEP, the electrode at records a spinal cord response: a) T12 b) CPz c) Iliac Crest d) the popliteal fossa - ANSWER--a) T12 Projecting laterally from the junction of the pedicle and lamina, and serving as a lever form muscle and ligaments, are the : a) intervertebral discs b) mamillary processes c) intervertebral foramen d) transverse process - ANSWER--d) transverse process Synaptic transmission, and/or changes in the thalomocortical projections, are believed to reproduce? a) subcortical potentials b) cortical potentials c) the Erb's point potential d) the P100 potential - ANSWER--b) cortical potentials The section of the brainstem that is continuous with the spinal cord and includes the decussaton of the pyramids, is the? a) medulla oblongata b) pons c) dorsal column d) midbrain - ANSWER--a) medulla oblongata The ulnar nerve originates from nerve roots at? a) C5-C6 b) C6-C7 c) C7-C8 d) C7-T1 - ANSWER--d) C7-T1 The gain of an amplifier, set to give an output signal of 1 volt for an input signal of 10 UV, is: a) 100 b) 1000 c) 10,000 d) 100,000 - ANSWER--d) 100,000 The following are examples of good insulating materials, inhibiting current flow: a) silicon and germanium b) silver and copper c) glass and rubber d) gold and platinum - ANSWER--c) glass and rubber In selecting the horizontal parameter of analysis, the: a) sampling rate should be at least two times greater than the highest frequency in the signal b) sampling rate should be the equivalent of the highest frequency in the signal c) analysis period should be at least twice the Nyquist frequency d) analysis period should approach the Nyquist frequency - ANSWER--a) sampling rate should be at least two times greater than the highest frequency in the signal Which of the following can inhibit the postsynaptic neuron? a) gamma amino butyric acid (GABA) b) acetylcholine c) para amino butyric acid d) glutamate - ANSWER--a) gamma amino butyric acid (GABA) The median nerve originates from nerve roots? a) C5 -T1 b) C3 -C7 c) C5 - C6 d) C4 - C6 - ANSWER--a) C5 - T1 The peroneal and tibial nerves are divisions of the: a) brachial plexus b) deep peroneal nerve c) sciatic nerve d) lumbar plexus - ANSWER--c) sciatic nerve Spinal nerves are attached in series to the sides of the spinal cord and emerge through the? a) filum terminale b) lamina c) spinous process d) intervertebral foramina - ANSWER--d) intervertebral formina P14 is a far-field, subcortically generated response which probably reflects? a) activity from the precentral gyrus (motor strip) b) caudal medial lemniscal activity c) passage of the afferent volley d) a stationary cervical potential - ANSWER--b) caudal medial lemniscal activity The assumption that responses of excessive amplitude are likely to contain artifact forms the basis of: a) digital filtering b) dwell time c) artifact rejection d) digital averaging - ANSWER--c) artifact rejection d) 30 minutes - ANSWER--d) 30 minutes A contraindication for the use of transcranial magnetic stimulation is: a) patient obesity b) a cardiac pacemaker in place c) multiple sclerosis d) transverse myelitis - ANSWER--b) cardiac pacemaker in place In order to assess the stimulating circuitry, stimulating electrodes, and the peripheral nerve while recording SSEPs intraoperatively, the peripheral nerve should also be recorded: a) INM b) CAP c) CEA d) TCeMEP - ANSWER--b) CAP Preoperative baseline, sensory evoked potential values are essential to intraoperative neurophysiological monitoring because: a) latencies and amplitudes are highly variable b) it is necessary to compare intraoperative values with laboratory normative date c) absolute boundaries for EPs obtained intraoperatively are not available d) they help to establish the appropriate level of anesthesia - ANSWER--c) absolute boundaries for EPs obtained intraoperatively are not available A patient is admitted to the operating room diagnosed with a herniated cervical disc at C5/6. The most appropriate nerves to monitor during the resulting surgical procedure would be the? a) tibial and ulnar nerves b) median and posterior tibial nerves c) median and auditory nerves d) ulnar nerve - ANSWER--b) median and posterior tibial nerves The median nerve SSEP can be helpful as a measure of? a) cerebral blood flow b) lower spinal cord funtion c) blood pressure variability d) anesthetic sensitivity - ANSWER--a) cerebral blood flow Spinal cord evoked potentials are best recorded using a low-frequency filter setting of 100Hz. This setting is preferred because, relative to cortical somatosensory evoked potentials, spinal cord potentials are: a) of relatively short duration b) less affected by changes in anesthesia c) subject to 60 Hz interference d) an extremely low voltage response - ANSWER--a) of relatively short duration In the operating room, the stimulus intensity for activating a sensory nerve: a) should be set at double the sensory threshold b) should be set for two to three times the motor threshold c) does not have an established boundary d) is set slightly above motor threshold - ANSWER--c) does not have an established boundary The suggested rate of stimulation for intraoperative posterior tibial nerve evoked potential monitoring is: a) 30 to 40 per second b) 20 to 30 per second c) 10 to 20 per second d) 2 to 10 per second - ANSWER--d) 2 to 10 per second To record cortical SSEPs during intraoperative monitoring of cervical spinal cord surgery, electrodes should be placed: b) frequency as a linear display across the epoch line c) time horizontally on the graph d) time as a spectral edge - ANSWER--b) frequency as a linear display across the epoch line When monitoring somatosensory evoked potentials during a critical moment in an intraoperative study, changing the setting of the high-frequency filter a) will be of limited consequence to the outcome of the study b) may help isolate a true signal from background noise c) may increase the number of single trial events required to resolve the evoked potentials d) may lead to false interpretation of the data - ANSWER--d) may lead to false interpretation of the data Stimulation of the spinal cord to elicit motor evoked potentials is most useful for monitoring: a) anterior spinal cord function b) dorsal column function c) peripheral nerve function d) ascending spinal cord tracts - ANSWER--a) anterior spinal cord function When monitoring the facial nerve: a) long-lasting muscle relaxants must be avoided b) bipolar electrodes should be placed in the larynx c) needle electrodes should be placed in the masseter d) inhalational anesthetic agents must be avoided - ANSWER--a) long-lasting muscle relaxants must be avoided An appropriate BAEP stimulation rate to avoid synchronization with 60 Hz artifact, would be: a) 6 per second b) 9.5 per second c) 10 per second d) 20 per second - ANSWER--b) 9.5 per second Vascular malformations of the posterior fossa associated with hemifacial spasm and facial paresis may cause: a) a loss of Wave I on the BAEP b) BAEP latency abnormalities c) increased amplitude if tubal inserts are used for stimulation d) BAEP abnormalities if the auditory cortex is involved - ANSWER--b) BAEP latency abnormalities At the stage of surgical anesthesia, propofol affects the BAEP by: a) increasing the latencies of Waves I, III and V without changing their amplitudes b) decreasing the amplitude in all waveforms c) causing very minimal changes d) abolishing all waveforms - ANSWER--a) increasing the latencies of Waves I, III and V without changing their amplitudes Functional cortical stimulation is used to localize brain areas that must be: a) identified before clamping b) most at risk during aneurysm clipping c) monitored futher by somatosensory EPs d) preserved during resection - ANSWER--d) preserved during resection The surgical procedure that would have the greatest risk for changes in cardiovascular and respiratory efforts would: a) involve the posterior fossa b) be the removal of an occipital tumor c) be temporal lobectomy d) be in the area of the posterior spinal segments - ANSWER--a) involve the posterior fossa a. cortical ischemia from carotid artery compression b. paraplegia due to compromise of the artery of Adamkiewicz c. quadraparesis due to ischemia in the upper thoracic spine d. kinking of the subclavian artery with ischemia to the upper arm - ANSWER--c. quadraparesis due to ischemia in the upper thoracic spine Stimulus artifact during SSEPs can be decreased by: a. Separating stimulating cables from cables of other equipment b. Keeping the instrument away from fluorescent lights and video monitors c. Lowering the impedances of ground and stimulating electrodes d. Using enough muscle relaxant - ANSWER--c. Lowering the impedances of ground and stimulating electrodes Middle cerebral artery supplies: (select all that apply) a. mouth area of cerebral cortex b. hand area of cerebral cortex c. face area of cerebral cortex d. auditory area of cerebral cortex - ANSWER--all of the above With exposure provided by laminectomy, needle electrodes can record spinal activity with placement: a. in the spinal muscle b. in the pedicle c. on the spinal cord d. in the epidural space - ANSWER--d. in the epidural space D-wave cannot be recorded below: a. L1 b. D-wave can be recorded from any spinal level c. T9 d. T6 - ANSWER--a. L1 Universal precautions eliminate potential contact with body fluids that transmit: a. Electrical current b. Bacteriostatic viruses c. Meningitis d. Bloodborne pathogens - ANSWER--d. Bloodborne pathogens Monitoring of muscle relaxation is usually done with the train of four. Which of the following is true? a. relaxation is measured by counting the number of muscle responses to 4 stimuli at 2 Hertz b. relaxation is monitored by examining the muscle contractions to continuous stimulation at 4 Hertz c. relaxation is monitored by examining the CMAP to four rapid stimuli and 500 Hz - ANSWER--a. relaxation is measured by counting the number of muscle responses to 4 stimuli at 2 Hertz In order to assess the stimulating circuitry, stimulating electrodes, and the peripheral nerve while recording SSEPs intraoperatively, the peripheral nerve should also be recorded. a. CAP b. CEA c. INM d. TCeMEP - ANSWER--a. CAP What is the definition of a propagated response and give an example of one? a. N13 in the upper SSEP. The electrode moves and only the amplitude changes b. N9 response in the upper SSEP. The electrode moves and so does the latency c. p37 response in the lower SSEP. The electrode moves and so does the latency d. Wave V in BAEP - ANSWER--b. N9 response in the upper SSEP. the electrode moves and so does the latency The brain and spinal cord is thought to autoregulate its blood flow over a range of blood pressures. Is it safe to lower the blood pressure in all patients to a mean blood pressure of 50 mmHg? a. No b. Yes - ANSWER--a. No A "ground loop" is created when: Which of the following monitoring modalities is affected the least by 1 MAC of desflurane? a. cortical auditory evoked potentials b. Epidural recording of transcranial motor evoked potentials (D wave) c. Compound muscle action potential recording of transcranial MEP d. Cortical somatosensory evoked potentials - ANSWER--b. Epidural recording of transcranial motor evoked potentials (D wave) The recommended location for recording the cervical cord responses to median nerve stimulation is: a. C8 b. C1 c. C2 d. C5 - ANSWER--d. C5 When running T-EMG, what are you recording? a. CMAP b. SSEP c. SNAP d. MEP - ANSWER--a. CMAP With significant changes in cervical and cortical SSEPs during intraoperative monitoring, adequate stimulation of the median nerve is indicated by: a. consistent anesthetic levels b. no change in the peripheral responses c. a persistent thumb twitch d. a loss of peripheral response - ANSWER--b. no change in the peripheral responses The phenomenon called "aliasing": a. refers to an erroneous representation of an analog signal by digital values b. occurs when the analysis period is more than twice the nyquist frequency c. Is common during intraoperative recording of evoked potentials d. may be avoided by proper placement of the ground and stimulating electrodes - ANSWER--a. refers to an erroneous representation of an analog signal by digital values Grey matter region in the brainstem in which cranial nerve neurons form synapses with neurons of the brainstem: a. Corpus Callosum b. Cranial Nerve Nucleus c. Posterior Horn Cells d. Anterior Horn Cells e. Ventricles - ANSWER--b. Cranial Nerve Nucleus When the patient's core and limb temperatures drop, what changes in the SSEP would one expect to see? a. increase in amplitude and latency b. increase in latency only c. decrease in amplitudes d. decrease in amplitude and latency - ANSWER--b. increase in latency only To optimally monitor cranial nerve VIII function in the operating room, it is desirable to be able to simultaneously perform: a. BAEPs and SSEPs b. BAEPs and electrocochleograms (ECochG) median SSEPs and CMAPs d. BAEPs and EEEP - ANSWER--b. BAEPs and electrocochleograms (ECochG) It is most important that electrode impedances are balanced. Ideally, sub-dermal electrode impedances would be between what range? a. 5-7 Ohms b. 5k-7 K Ohms c. 12k=20 K Ohms d. 9k-11 K Ohms - ANSWER--b. 5k - 7 K Ohms A differential amplifier, amplifies and records: a. only the first two inputs b. the power of the sum of the two inputs c. the second half of the two inputs c. the second half of the two inputs a. pancuronium b. robinol c. succinylcholine d. ethrane - ANSWER--c. succinylcholine All of the following should be annotated on the flow sheet except: a. the computer time b. what converstaions occurred between you and the surgical team c. the date d. when the surgeon came into and out of the room - ANSWER--d. when the surgeon came into and out of the room Which of the following anesthestic agents is not a good amnestic? a. dexmeditomidine b. etomidate c. propofol d. midazolam - ANSWER--a. dexmeditomidine Neurological syndrome caused by a lesion such as a tumor, trauma such as a gun shot or puncture wound, ischemia, infectious or inflammatory disease such as tuberculosis or multiple sclerosis, resulting in disturbances of tactile and kinesthetic sense on the side of the lesion with reduced muscle tone and reflexes and on the side contralateral to the lesion loss of pain sensation at or one segment below the lesion and loss of thermal sense from about two segments below the lesion. a. Tourette syndrome b. frey's syndrome c. brown-sequard syndrome d. carpal tunnel syndrome e. guillain-barre syndrome - ANSWER--c. brown-sequard syndrome Preoperative EEG baseline recordings are obtained: a. before incision b. after incision c. 24-48 hours after completion of the Carotid Endarterectomy d. during clamp time - ANSWER--a. before incision What should an IONM professional document during surgery? (select all that apply) a. times in which other OR staff (circulator and scrub tech) enter and exit the room b. pertinent discussion with surgeon and other OR staff c. offhand comments and good jokes told during surgery d. changes and corrective action taken e. surgical events f. troubleshooting g. anesthetic levels h. patient's physiologic state - ANSWER--b. pertinent discussion with surgeon and other OR staff d. changes and corrective action taken e. surgical events f. troubleshooting g. anesthetic levels h. patient's physiologic state An EP recording system should allow averaging of: a. no more than 500 trials (sweeps) b. no more than 100 trials (sweeps) c. at least 4000 trials (sweeps) d. a maximum of 200 trials (sweeps) - ANSWER--c. at least 400 trials (sweeps) When filtering a signal that is 20 Hz with a 20 Hz with a 20 Hz high frequency filter, what happens to the timing of the signal? a. it shifts the timing forward and leads the input signal and amplitude is decreased b. it lags behind the input signal and amplitude attenuated c. the signal would remain unchanged in timing or amplitude d. nothing, the signal would be unchanged only the amplitude will be deminished - ANSWER--b. it lags behind the input signal and amplitude attenuated Which technique is most useful in monitoring the integrity of corticospinal tracts during resection of intramedullary spinal cord tumors? a. H-reflex Which of the following changes effect Intraoperative Monitoring (IOM) recordings? (select all that apply) a. atmospheric b. pharmacological c. mechanical d. geographical e. physiological - ANSWER--b. pharmacological c. mechanical e. physiological The use of the 60 Hz notch filter is discouraged while recording because it can: a. filter slow activity, distorting the response b. cause the recording electrodes to form a salt bridge c. produce ringing activity that can contaminate the appearance of the response d. produce a risk to the patient - ANSWER--c. produce ringing activity that can contaminate the appearance of the response It is important to put a note in the chart: a. as an attestation that you actually were present doing the monitoring b. so a professional fee can be billed c. to prove you looked at the chart d. in case the circulating nurse doesn't remember your name - ANSWER--a. as an attestation that you actually were present doing the monitoring Which of the following statement sis true of microembolic signals? a. they occur only in the systolic phase of the cardiac cycle b. they have a short duration of <0.1 seconds c. they have lower intensity reflection than blood d. they are usually bidirectional - ANSWER--b. they have a short duration of <0.1 seconds What mixed nerve contains only a small motor component to the stylopharyngeus muscle can be monitored by placing recording electrodes in the lateral aspect of the soft palate? a. trochlear nerve (cn IV) b. vagus nerve (cn X) c. Oculomotor Nerve (CN III) d. Glossopharyngeal Nerve (CN IX) - ANSWER--d. glossopharyngeal nerve (CN IX) When monitoring somatosensory evoked potentials during a critical moment in an intraoperative study, changing the setting of the high-frequency filter: a. may increase the number of single trial events required to resolve the evoked response b. may help isolate a true signal from background noise c. may lead to a false interpretation of the data d. will be of limited consequence to the outcome of the study - ANSWER--c. may lead to a false interpretation of the data A shift of the compressed spectral arrays spectral edge indicates a. an increase or decrease of EEG frequency b. a significant change that always should be communicated to the surgeon c. artifact from a fluid warmer is detected d. an increase or decrease of EEG amplitude - ANSWER--a. an increase or decrease of EEG frequency The mental protruberance is located a. in the brain b. on the chin c. at the vertex of the skull d. in the cervical spine e. on the forehead - ANSWER--b. on the chin Your intraoperative date is admitted into evidence because: (select all that apply) a. it indicates inappropriate monitoring was performed b. it implies liability on the part of the surgeon c. it indicates a problem was observed but not communicated to surgeon d. it indicates appropriate monitoring was performed by the technologist - ANSWER--all of the above a unit of resistance or impedance is symbolized by: Capacitors are electronic devices used to: a. measure electrode impedance at the scalp b. stop current flow when some critical power level is exceeded c. enhance current flow d. store electrical energy - ANSWER--c. enhance current flow Roccuronium is an example of what type of muscle relaxant? a. long acting b. nondepolarizing c. depolarizing d. it is not a muscle relaxant - ANSWER--b. nondepolarizing Mixing electrodes made of various electrode metals is discouraged because: a. creates a lower averaged current density b. it creates a lower averages current density c. introduces artifact because it introduces a "difference" in the inputs that can be amplified by the differential amplifier - ANSWER--c. introduces artifact because it introduces a "difference" in the inputs that can be amplified by the differential amplifier In order to stimulate both tibial nerves asynchronously, you need: a. to delay the first stimulator b. a positive trace delay c. to delay the second stimulator d. a negative trace delay - ANSWER--c. to delay the second stimulator Perfusion pressure to the central nervous system (select all that apply) a. may be varied by disease processes b. may be compromised by occlusive disease c. may vary during daily activities d. may be varied by drugs - ANSWER--all of the above Which type of EMG response is suggestive of some degree of neural insult? a. train b. burst c. silence - ANSWER--a. train The effect of severe hypotension on the evoked potential includes: a. a decrease in amplitude and an increase latency b. an increase in amplitude and a decrease in latency c. a decrease in amplitude and variable changes in latency d. variable changes in amplitude and an increase in latency - ANSWER--a. a decrease in amplitude and an increase latency What are common alarm ccriteria for changes in SSEPs? a. 50% decrease in amplitude, 10% decrease in latency b. 50% increase in amplitude, 10% decrease in latency c. 50% increase in amplitude, 10% increase in latency d. 50% decrease in amplitude, 10% increase in latency - ANSWER--d. 50% decrease in amplitude, 10% increase in latency Monitoring modalities most likely affected by a large bolus of muscle relaxant is: a. subcortical SSEPs b. Cortical SSEPs c. EEG d. TCeMEP - ANSWER--d. TCeMEP The most common mode rejection ratio of amplifiers used for EP recording should be at least: a. 100,000: 1 b. 100:1 c. 1,000:1 d. 10,000:1 - ANSWER--d. 10,000:1 Where are compound muscle action potentials (CMAP) recorded? a. spine b. muscle c. nerve a. halogenated agents b. NO2 and propofol c. sevoflurane and muscle relaxants d. TIVA - ANSWER--d. TIVA Which type of instrumentation is most likely to cause trauma to the spinal cord? a. subdural needle electrodes b. the strain guage c. sublaminar wires d. the Wyatt bolt - ANSWER--c. Sublaminar wires A rarefaction click occurs when the: a. movement of a transducer diaphragm alternates in polarity relative to the tympanic membrane on a random basis b. initial movement of a transducer diaphragm is away from the tympanic membrane c. movement of a transducer diaphragm alternates in polarity relative to the tympanic membrane every second trial d. initial movement of a transducer diaphragm is towards the tympanic membrane - ANSWER--b. initial movement of a transducer diaphragm is away from the tympanic membrane Onset of anesthetic regimen until balanced anesthesia is achieved: a. inhalational agent b. MAC c. induction d. nitrous - ANSWER--c. induction Excitation of the postsynaptic neuron is caused by the neurotransmitter: a. glutamate b. para amino butyric acid c. glycine d. gamma amino butyric acid - ANSWER--a. glutamate Triggered EMG is used to monitor: (select all that apply) a. location of a specific nerve root b. testing the integrity of a specific nerve root c. placement of pedicle screws - ANSWER--all of the above Frequency burst on sustained high frequency discharges observed during spontaneous EMG monitoring may indicate what? a. deepening levels of anesthesia b. postoperative weakness or postoperative paralysis c. changes in blood pressure - ANSWER--b. postoperative weakness or postoperative paralysis The general range of amplitude of EKG is a. 1-2 millivolts b. 1-2 kilovolts c. 1-2 microvolts d. 1-2 volts - ANSWER--a. 1-2 millivolts Which of the following anesthetics enhances evoked responses? a. etomidate b. ketamine c. propofol - ANSWER--a. etomidate Synaptic transmission, and/or changes in the thalamocortical projections, are believed to produce: a. subcortical potentials b. cortical potentials c. the P100 potential d. the Erb's point potential - ANSWER--b. cortical potentials The blood supply to the medulla is primarily from: a. internal carotid artery b. vertebral artery c. posterior cerebral artery d. posterior communicating artery - ANSWER--b. vertebral artery