ABRET CNIM Exam 2023 Questions and Answers

What type of actions potentials contribute to the popliteal fossa - Answer- both orthodromic and antidromic What is the neurological deficit related to the compression of the spinal cord - Answer- Myelopathy When evaluating for special considerations/contraindication for MEP monitoring, what is the most appropriate step to be taken when identifying a pt with a previous medical history of SZs that have been well controlled with medication - Answer- discuss the risk with surgeon and anesthesiologist and proceed as they wish Creutzfeldt-Jakob disease is caused by - Answer- Prion proteins Which of the following is an analog to N34 - Answer- N18 Which of the following is NOT required to be part of an IONM record - Answer- patients medication history The most frequent source of a patient infection in the OR is derived from - Answer- Patients own endogenous flora Which nerve is at greatest risk when debulking a tumor larger than 3cm in diameter during CPA surgeries - Answer- Facial If an evoked potential has a voltage of 10uV and the associated noise has a voltage of 50uV, what is the signal-tonoiseratio after 100 averaged responses? - Answer- 2:1 Which of the following is within the scope of practice for a CNIM - Answer- obtain physiological data from central and peripheral nervous systems What is the MINIMUM sampling rate for the Nyquist frequency - Answer- More than double the fastest frequency of the waveform What is the most appropriate filter bandpass setting for recording the short latency median nerve SSEP - Answer- 30 to 3000 Hz What modalities are ideal to run on a Chiari malformation decompression - Answer- TCeMEPs SSEPs BAEPs The Nyquist frequency is based on - Answer- sampling rate and frequency of components MRI conditional electrodes are made from which of the following? - Answer- Nickel titanium What is the segmental motor innervation of the peroneus longus - Answer- L4,L5 and S1 Subdermal needles placed in the epidural space should be placed by the - Answer- surgeon This cranial nerve's function is to transfer visual information form the retina to the brain - Answer- optic Impedance is the opposition to - Answer- alternating current flow Which of the following is a positively charged electrode - Answer- anode D waves are recorded from which of the following electrodes - Answer- epidural electrodes over the spinal cord Motor nerve - Answer- Cranial nerve 3 What neurotransmitter is released at the neuromuscular junction? - Answer- acetylcholine what cranial nerve is purely motor - Answer- Oculomotor If 100 trials are required to achieve a signal-to-noise ratio of 2:1, how many trials must be theorectically averaged to increase the signal-to-noise ratio to 20:1? - Answer- 10,000 What is the most frequent mode of infection transmission, which can be either direct or indirect - Answer- Contact During CEA, what SSEP modality is recommended for monitoring cerebral function - Answer- median The use of IONM during scoliosis surgery may replace the - Answer- Stagnara test What is likely to result from a positional compression of the brachial plexus - Answer- thoracic outlet syndrome the flexion of the 4th and 5th digits of the hand would represent stimulation of the following nerve - Answer- ulnar nerve Saddle area sensory loss suggest a lesion in which area - Answer- cauda equina what modalities should you monito for CEA surgery - Answer- Ipsilateral EEG, Contralateral SSEP Ratio of amplifier output voltage to input voltage - Answer- Recording gain Which of the following cranial nerves is most appropriate to monitor during resection of a 4cm vestibular schwannoma - Answer- facial items that contact mucous membranes or non-intact skin are semi-critical and require what level of disinfection - Answer- high level when performing IOM for an intraoperative MRI case, use of electrodes that are not MRI-conditional may result in - Answer- Thermal burns Alternating current is used when checking electrode impedance to - Answer- avoid electrode polarization Ohm's Law - Answer- V=IR Damage to which structure would be MOST likely to result in motor deficits - Answer- lateral corticospinal tract If an amplifier has a common mode rejection ratio of 100:1, what is the corresponding dB - Answer- 40 Upper extremity SSEPs are transmitted through which spinal cord tract - Answer- Fasciculus cuneatus Which of the following would most affect the ability to record BAEPs - Answer- Coagulator What part of the spinal cord is most at risk for ischemia - Answer- thoracic A Babinski's sign in an adult - Answer- Indicates an upper motor neuron lesion which of the following frequencies is attenuated by a high frequency filter of 70Hz - Answer- 80 Hz Which of the following is the most sensitive setting per division - Answer- 10 microvolts during a neurological exam, which of the following cranial nerves would be included for evaluating extra ocular movements - Answer- III, IV, VI A preoperative IONM patient evaluation including review of medical records, history taking, focused examination and description of IONM is the responsibility of - Answer- IONM tech and Supervising professional to ensure electrical safety of the patient in the OR, maximum leakage current through patient leads should be - Answer- 10 uA rms Receptive aphasia is associated with damage to which neural structure - Answer- Posterior part of the superior temporal gyrus the zygomatic branch of CN VII innervates which muscle - Answer- Orbucularis Oculi Epidural electrodes are made of platinum because - Answer- other metals may become toxic when currents applied when removing a pituitary tumor via the nasal passage, the surgeon must produce a hole in what - Answer- Sphenoid when placing a stimulator probe on the ankle for IONM SSEP, monitoring of the lower extremities for an ACDF, which of the following is most appropriate - Answer- never wrap tape or band completely around the ankle which section of the spinal cord is considered a watershed zone - Answer- thoracic which of the following suffixes best describes a surgical operation that refers to a removal of something - Answer- -ectomy which of the following opposes any change in current - Answer- Inductance what is a slow growing tumor that can directly affect balance and hering - Answer- acoustic neuroma what statement about a notch filter is NOT correct - Answer- Using a notch filter on a free-run EMG will cause a ringing effect the dorsal column pathways synapse at which location on their way to the sensory cortex - Answer- Nucleus cuneatus and thalamus in the visual pathway, fibers anterior to the optic chiasm are called - Answer- optic nerves The ability of an amplifier to accurately cancel voltages that are common to both inputs - Answer- CMRR Most effective method to monitor spinal motor pathway during surgery is - Answer- multi-pulse transcranial electric stimuli with recording from lower extremity muscles Bell's Palsy - Answer- facial nerve Which of the following medical terms means on top or upon - Answer- Epi- which CNs should be monitored during a MVD for trigeminal neuralgia - Answer- V and VII plain radiographs are required for patients with - Answer- scoliosis The ability to cancel in phase signals and record out of phase signals can be best described as: - Answer- common mode rejection which of the following IONM modalities would be most appropriate for an MVD - Answer- EMG and BAEP During the untethering of a tethered cord, what is severed? - Answer- Filum terminale what cranial nerve allows turning the head and lifting the shoulders - Answer- 11 which of the following would result in the best resolution in the analog-to-digital conversion process - Answer- the maximal peak-to-peak signal amplitude should match the converter range when is the latest acceptable time during a surgery to begin monitoring - Answer- before any surgical manipulations which place neural structures at risk Snellen Chart - Answer- used to measure visual acuity the blood supply to the spinal cord is predominantly provided by - Answer- anterior spinal artery thoracic outlet syndrome may include the following signs and symptoms EXCEPT - Answer- sacral plexus compression What type of glial cells make up the myelin sheath of the peripheral nervous system - Answer- schwann lower motor neurons primarily exit the spinal cord through - Answer- ventral nerve roots If baseline SSEPs are small in amplitude, what troubleshooting step should you take to improve responses? - Answer- Increase pulse duration According to ACNS Guidelines, what is the minimum required vertical resolution for an A-D converter - Answer- 8 bits Recording of median nerve SSEPs during carotid endarterectomy is a useful adjunct to EEG for detecting - Answer- ischemia in the middle cerebral artery What abnormality can a defect in the lower motor neurons cause - Answer- Flaccid paralysis The triceps and extensor carpi ulnaris muscles can be good locations to monitor EMG when surgery is close to - Answer- C7 nerve root which of the following best describes the expected EEG changes during an intracarotid amobarbital (Wada) procedure - Answer- slow activity in the hemisphere ipsilateral to the injection which of the following is LEAST likely to cause 60 hz artifact during BAEPs - Answer- Pneumatic drill A loss of balance upon closing one's eyes while standing upright indicates a positive: - Answer- Romberg's sign Which motor and sensory findings are consistent with Brown-Sequard Syndrome? - Answer- contralateral loss of pain and temperature sensation and ipsilateral loss of motor function If an amplifier is rated as having 120dB common mode rejection ratio, which of the following ratios of in-phase to out-of-phase signals would be expected? - Answer- 1,000,000:1 Standard (universal) precautions are used to reduce the transmission of - Answer- bloodborne pathogens A dystonic condition, which causes the neck to twist to one side and the head to tilt: - Answer- torticollis which of the following ions are involved in a neuronal action potential - Answer- Potassium (K+) and Sodium (Na+) Compression of which nerve root would cause a shoulder abduction - Answer- C5 Where is the central relay station for sensory information that is located between the cerebrum and spinal cord - Answer- Thalamus Shortened sternocleidomastoid muscle - Answer- Torticollis Which is the best monitoring strategy during a posterior myelotomy procedure - Answer- SSEPs, EMG, TcMEPs Occipital lobe receives its blood supply directly from which artery - Answer- posterior cerebral when placing subdermal electrodes, tech should - Answer- secure the needles in place with tape or tegaderm what is a chronic autoimmune disease that affects the myelin sheath of the central nervous system, causing a wide range of symptoms - Answer- Multiple Sclerosis During a C5 foraminotomy, the train free-run EMG is seen in the right deltoid channel. All of the following may be causing this activity EXCEPT - Answer- Ischemia of the nerve Special considerations/contraindications for TCeMEP include all the following EXCEPT - Answer- diabetes what would be the most appropriate muscle to use when asked to monitor cranial nerve III - Answer- inferior rectus if a neurologist suspects nerve damage in a pt's neurological exam, they may order - Answer- nerve conduction /EMG myelopathy - Answer- spinal cord compression Which modality is sued as a diagnostic tool for MS - Answer- SSEP In which type of EP is the scalp position of recording electrodes most critical - Answer- Lower extremity SSEPs what type of glial cells make up the myelin sheath of the central nervous system - Answer- Oligodendrocytes Current - Answer- amount of electrons flowing between two points A typical SSEP stimulus has a pulse width between: - Answer- 100-300 microseconds Pop fossa distal and proximal electrodes should be placed midline of the pop fossa and what is the distance that they should be from the pop crease - Answer- 2 cm and 5 cm respectively Which of the following is a clinical indication of a lower motor neuron lesion - Answer- Fasciculation Translabyrinthine Approach - Answer- Cerebello-pontine angle tumor Which element in the patients history may cause the SEP stimulation to fail - Answer- Peripheral neuropathy Medical history relevant to IONM for a thoracic aortic aneurysm repair includes - Answer- associated symptoms, associated Crawford levels and pervious neurological deficits lateral curvature of the spine - Answer- scoliosis which of the following is most commonly associated with radiculopathy - Answer- nerve roots Brown-Sequard Syndrome - Answer- Spinal cord hemisection (compression) The ability to amplify the difference between two input voltages and the ability to cancel out any voltage common to the two inputs - Answer- Differential amplifier The surgical site for a posterior fossa tumor surgery requires adjustment of the standard SSEP recording electrodes. Which adjustments should be made? - Answer- move C5s lateral Which TcMEP wave is MOST affected by a bolus of 30 mg rocuronium? - Answer- I-Wave Upper extremity SSEPs are monitored during lumbar surgeries to evaluate - Answer- positioning and anesthetic effects Wada testing primar - Answer- language function Which of the following best describes spondylosis - Answer- Degenerative spine disease Penetration of the sterile surgical field occurs when - Answer- surgeons arms brushes against the recording equipment For a posterior L5-S1 decompression and fusion, which muscles should be monitored? - Answer- Gastrocnemius, tibialis anterior, abductor hallicus Which nerve innervates the adductor pollicis muscle - Answer- ulnar Which of the following cranial nerves relay sensory information ONLY - Answer- II To improve the signal-to-noise ratio by a factor of 100, what is the required # of responses to be averaged - Answer- 10,000 which cranial nerves function focuses on facial touch, temperature, sensation and mastication - Answer- Trigeminal What is indicated by the presence of unilateral babinski signs - Answer- pyramidal tract dysfunction if the signal to nose ratio of a raw signal is 1, how many trials must be averaged to achieve a signal to noise ratio of 4 - Answer- 16 Brief, fine, irregular twitches seen under the skin on a motor exam are known as - Answer- Fasciculations When is leakage current present in an evoked potential instrument? - Answer- whenever the instrument is connected to a power source A selective dorsal rhizotomy is associated with - Answer- Cerebral palsy and the severing of posterior rootlets to monitor the integrity of the facial nerve during a parotidectomy - Answer- stimulate proximally and record distally EP data are obliterated with - Answer- monopolar cautery Third ventricle is connected to the fourth ventricle by the - Answer- aqueduct of sylvius Narrowing of the spinal canal or a foramen - Answer- stenosis which of the following cranial nerves innervates the extraocular muscles - Answer- Abducens which cranial nerve travels above the cerebellopontine space - Answer- Trigeminal Due to the relative inexcitablity of the motor cortex in the pediatric population, direct cortical stimulation may not be suitable in patients less than - Answer- 5 years old which of the following is NOT part of the circle of willis - Answer- superior cerebellar artery Forward displacement of a vertebra which may cause moderate to severe back pain - Answer- spondylolisthesis a positive event occurring in the lead connected to the negative terminal, will result in a deflection - Answer- downward the anterior spinothalamic tract carries the sensory modalities of - Answer- crude touch what is the most common presenting symptom of intramedullary tumor - Answer- Pain what is an autosomal recessive inherited disease that affects the spinocerebellar tracts, posterior columns and dorsal root ganglion resulting in ataxia, muscle weakness, loss of coordination, speech impairment and curvature of the spine - Answer- Friedreich's Ataxia Which modalities should you monitor for a C7 fracture - Answer- Ulnar nerve and PTN Resection of skull base tumors in the cerebellopontine angle may reduce the blood flow to which of the following vessels? - Answer- AICA What is the signal-to-noise ratio after 64 trials if an EP has a voltage of 50uV and the noise measures 100uV - Answer- 4:1 How often are national patient safety goals released - Answer- annually which one of the following in an excitatory neurotransmitter - Answer- Glutamate An 8 bit analog-digital conversion has which of the following voltage levels - Answer- 256 Prior to IONM for a posterior lumbar interbody fusion, the tech should obtain a relevant medical history which should include - Answer- sensory or motor related issues and recent radiology findings Which of the following cranial nerves is a mixed nerve - Answer- CN V 67 year old patient with long standing history of diabetes mellitus type II, is scheduled for IONM, he also has a left foot drop. Which nerve compression is responsible for foot drop - Answer- common peroneal nerve to display a tibial nerve SSEP response as a downward deflection, which of the following must be known - Answer- polarity of the response and the polarity convention of amplifier inputs what is the required vertical resolution of an EP system - Answer- 16 bits What is the minimum CMRR required for EP amplifiers - Answer- 80 dB The two vertebral arteries pass through foramen magnum and unite to form - Answer- the basilar artery number of data points and the sweep time determine - Answer- horizontal resolution What spinal disorder causes a forward displacement of the vertebra that is commonly seen in the 5th lumbar vertebra? - Answer- Spondylolisthesis what is the recommended analysis time for TcMEP recording - Answer- 100msec Positive Babinski sign is seen as - Answer- fanning of toes what modalities should you monitor for a vestibular neurectomy procedure - Answer- Ipsilateral BAER and facial nerve EMG what vertebral levels do the fasciculus gracilis carry info from - Answer- T7 and below what nerve should be monitored if the surgeon is concerned about foot drop - Answer- L5 and peroneal which organization is responsible for overseeing accreditation and certification standards and sets initiatives for National Patient Safety Goals in the United States - Answer- TJC The artery of adamkiewicz originates between - Answer- T8-L1 Following SSEP stimulation of peripheral nerve, the pathway ascends through the: - Answer- ipsilateral dorsal columns spondylosis - Answer- degeneration of the spine Conus medullaris is located at which level in adults - Answer- L1, L2 on a neurological motor exam, what does 4/5 strength indicate - Answer- Movement against resistance but less tha