When recording a ptn ssep - Study guides, Class notes & Summaries

White matter consists of what type of fiber tracts? - ANSWER-Axon of nerve fibers In the visual pathway, fibers anterior to the optic chiasm are called - ANSWER-Optic Nerves If a neurologist suspects nerve damage in a PTs neurological exam, he may order - ANSWER-Nerve conduction/EMG excitatory neurotransmitter - ANSWER-Glutamate The trigeminal nerve can be monitored from which muscle? - ANSWER-Masseter Damage to which structure would most likely result in motor deficits - ANSWER-Lateral ...

If you have high frequency noise in a BAEP: A100/100 pts Change HFF from 3000 to 1500 Hz Change HFF to 200 Hz Change LFF to 150 Hz Change LFF to 30 Hz - Answer- Change HFF from 3000 to 1500 Hz To dissect a vestibular schwannoma, which surgical approach usually sacrifices hearing? suboccipital retrosigmoid middle cranial fossa translabyrinthine - Answer- translabyrinthine According to current OSHA standards, needle electrodes should be reused whenever possible not be soaked i...

Universal precautions eliminate potential contact with body fluids that transmit: electrical current bloodborne pathogens meningitis bacteriostatic viruses - ANSWER-bloodborne pathogens When at the state of surgical anesthesia, the principal effect of Etomidate on evoked potentials is to: decrease amplitudes increase latencies increase amplitudes decrease absolute latencies - ANSWER-increase amplitudes The sensitivity setting on an amplifier set to produce a vertical deflection...

CNIM QUESTIONS WITH CORRECT ANSWERS Which of the following would best enhance resolution of evoked potential waveforms? - CORRECT ANSWER-Increase number of averaged stimuli What is the typical MINIMUM common mode rejection ratio of in-phase signals recommended for evoked potential instruments? - CORRECT ANSWER-10,000:1 Which of the following cranial nerves is most at risk during acoustic neuroma surgery? - CORRECT ANSWER-CN VII The impedance of cup electrodes is: - CORRECT ANSWER...

During a median nerve preoperative study, a patient has discomfort at the wrist. Stimulation electrodes are 10 mm gold disk, stimulus intensity is 20 mA, and stimulus duration is 100 μsec. Which of the following would most likely reduce the patient's discomfort while maintaining adequate stimulation? Decrease number of repetitions What is not an advantage of epidural recordings? Absence of significant artifact The stimulation rate is determined by the analysis time Soma...

What time constant would be the most effective for cutting out low frequency noise from your SSEP cortical responses? - Answer- Answer: 10 mS SSEP cortical responses are in the typical frequency range of 100-200 Hz. That being said, let's see what time constant would give us a good Low Frequency Filter. Remember LFF filters out everything below the cut off frequency and passes higher frequencies. Formula to know: Cut off Frequency = 1 / Time Constant (tc) 1/.01 s = 100 Hz 10 ms = ...

Ipsilateral cranial nerve deficits combined with contralateral motor deficits indicate what site of lesion? A- Cortex B- Cauda equina C- Brainstem D- Spinal cord - Answer- C Median Nerve A- MCA B- PCA C- AICA D- ACA - Answer- A The layers of protective tissue which surround the central nervous system are called: A- Ventricles B- Cerebrospinal fluidd C- Skull D- Meninges - Answer- D The interconnecting blood vessels at the base of the brain make up: A- Carotid exchange B- B...

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 anesthes...

Rostral to the cathode - Answer- For stimulation in MEP studies, the anode should be placed: A. rostral to the cathode B. lateral to the cathode C. Caudal to the cathode D. Medial to the cathode During anesthetic changes - Answer- Maximum variability of cortical EP potentials will most likely occur: A. After opening the surgical site B. During electrocautery C. Prior to lumbar laminectomy D. During anesthetic changes will increase the latency and decrease the amplitude of the ABR -...

During a median nerve preoperative study, a patient has discomfort at the wrist. Stimulation electrodes are 10 mm gold disk, stimulus intensity is 20 mA, and stimulus duration is 100 μsec. Which of the following would most likely reduce the patient's discomfort while maintaining adequate stimulation? - Answer- Decrease number of repetitions What is not an advantage of epidural recordings? - Answer- Absence of significant artifact The stimulation rate is determined by the - Answer- analys...