Advanced MEPs and SSEPs Exam
Actual Questions and Answers 2026
orthodromic -
correct answer ✅an impulse in an axon traveling in the
normal/natural direction
antidromic -
correct answer ✅an impulse in an axon traveling the opposite of
the normal/natural direction
What are NMEPs? -
correct answer ✅Early attempts to monitor motor pathways
intraoperatively using stimulation at the spinal cord above
operative site and recording from the peripheral nerves in the legs
what are the contraindications of NMEPs? -
correct answer ✅1. the NMEP response was abolished by dorsal
rhizotomy
2. collision studies confirmed the potentials were predominantly
sensory
3. false negative results appeared with this technique
, Advanced MEPs and SSEPs Exam
Actual Questions and Answers 2026
what is the goal of a dorsal root rhizotomy -
correct answer ✅to identify the dorsal rootlet contributing to
spasticity and sever it
how does a dorsal root rhizotomy eliminate spasticity -
correct answer ✅spasticity is caused by dorsal root stimulation
causing motor function. If we stim and get motor function that is
abnormal and the rootlet must be severed
what did collision studies confirm regarding NMEPs -
correct answer ✅NMEPs are antidromic sensory responses rather
than motor responses
what is the goal of collision studies -
correct answer ✅to confirm left and right activation with spinal
cord stimulation
how did collision studies discredit NMEPs? -
correct answer ✅no subcortical or cortical SSEP waveforms were
obtained because the antidromic sensory stimulation of the NMEPs
collided with the orthodromic sensory stimulation at the PTN
Actual Questions and Answers 2026
orthodromic -
correct answer ✅an impulse in an axon traveling in the
normal/natural direction
antidromic -
correct answer ✅an impulse in an axon traveling the opposite of
the normal/natural direction
What are NMEPs? -
correct answer ✅Early attempts to monitor motor pathways
intraoperatively using stimulation at the spinal cord above
operative site and recording from the peripheral nerves in the legs
what are the contraindications of NMEPs? -
correct answer ✅1. the NMEP response was abolished by dorsal
rhizotomy
2. collision studies confirmed the potentials were predominantly
sensory
3. false negative results appeared with this technique
, Advanced MEPs and SSEPs Exam
Actual Questions and Answers 2026
what is the goal of a dorsal root rhizotomy -
correct answer ✅to identify the dorsal rootlet contributing to
spasticity and sever it
how does a dorsal root rhizotomy eliminate spasticity -
correct answer ✅spasticity is caused by dorsal root stimulation
causing motor function. If we stim and get motor function that is
abnormal and the rootlet must be severed
what did collision studies confirm regarding NMEPs -
correct answer ✅NMEPs are antidromic sensory responses rather
than motor responses
what is the goal of collision studies -
correct answer ✅to confirm left and right activation with spinal
cord stimulation
how did collision studies discredit NMEPs? -
correct answer ✅no subcortical or cortical SSEP waveforms were
obtained because the antidromic sensory stimulation of the NMEPs
collided with the orthodromic sensory stimulation at the PTN
