CNIM - ABRET PRACTICE EXAM QUESTIONS
Cavities inside the skull - Answers -Anterior/middle/posterior fossa
Cranial bones - Answers -Frontal, occipital, sphenoid, ethmoid (unpaired). Parietal &
temporal (paired).
Mental protuberance - Answers -chin bone
MCA supply of the cerebral cortex - Answers -Hand + face/mouth/auditory
Cranial nerves - Answers --12 pairs (Mixed fibers: sensory/motor/both).
-Emerge @ irregular intervals from the brain.
-Nuclei displacement:
Motor = medial Sensory = lateral
Meckle's Cave - Answers -Depression in the medial middle fossa where CN V ganglion
sits
Low frequency sounds - Answers -@ apex of cochlea
Area of spine w/ small pedicles, long spinous process, large inter-vertebral foramen -
Answers -Thoracic
Neuroforamen - Answers -Opening w/in the spinal canal for nerve roots to enter the SC
Firm outer layer of the disc - Answers -Annulus fibrosis
Syrinx - Answers -Fluid-filled cavity @ center of the SC
Spinal cord ends @ the level btwn: - Answers -L1-L2 vertebrae (Conus Medullaris)
Blood supply to the SC consists of: - Answers -1 ASA for both MEP tracts
Hydrostatic pressure - Answers -Depends on body position
Structural functional anatomy may be altered by: - Answers -Previous lesions, current,
plasticity, pressure
Glia cell - Answers -Comes from the Greek word "glue"
Large diameter nerve fiber (vs. small diameter) - Answers --Recruited 1st w/ INC'd stim
intensity
-Higher conduction velocity
-More vulnerable to hypoxia & pressure Δ's
,Synaptic transmission, and/or Δ's in thalamocortical projections, produce - Answers -
Cortical potentials
Peripheral nerve sensitivity - Answers -Least sensitive to injury (more sensitive = SC
grey/white mater, cortical grey matter)
Cavernous angiomas - Answers -Multi-lobulated lesions containing hemorrhage
Geriatric population: prevalence of temporal bone hyperostosis - Answers -10-15%
Presbycusis - Answers -High freq hearing loss; gradually occurs in older individuals
Most commonly injured CN - Answers -Facial nerve (VII)
Burst fracture - Answers --Break in the vertebra
-Failure of anterior & middle vertebral columns
-Caused by violent compressive event (fall, MVA)
Excessive neck flexion in sitting position - Answers -Quadraparesis (due to ischemia in
upper T-spine)
Lhermittes Sign - Answers -Shocking sensation that occurs throughout the body during
neck flexion
Central Cord Syndrome (CCS) - Answers --Sacral sparing
-Loss of sensory/motor fx @ level of injury
-Disruption of grey matter
(+) Babinski Sign could indicate - Answers --severe [UMN] SC trauma
-abnml PTN SSEPs
Hoffman's Reflex (1918) - Answers -Palmar flexion of the thumb when the distal phalanx
of the middle finger (of the same hand) is rapidly stroked
A nml curve of the lumbar spine taking place @ 1-2 y/o - Answers -Kyphosis
Scoliosis progression in peds - Answers -More likely in girls > boys
Apraxia - Answers -Difficulty w/ skilled mvmnts
Neurapraxia - Answers -PNS disorder: blockage of sensory + motor nerve conduction
(w/o axonal damage)
INC venous pressure leads to - Answers --venous congestion; DEC drainage of nml
veins; chronic hypoxia
-NOT hypotension
, common source of air embolism introduction into the blood supply - Answers -Superior
sagittal sinus
MAC is approximated by the effect of anesthesia on - Answers -H-reflex (mvmnt when
stimulated)
Sevo/Des/N2O - Answers -DO NOT act on the same neuronal receptors
On an equi-MAC basis (w/ equivalent doses of anes), which has the greatest effect on
MEPs of recorded mm's? - Answers -N2O
N2O - Answers --synergistic IONM effects when mixed w/ Iso --> depressed IONM
-weak anesthetic agent
-causes ~75% DEC in SSEP amplitudes
Desflurane - Answers --affects NMJ --> enhances effect of NMBs
-no effect on MEP CMAPs
-eliminates most rapidly
Isoflurane 1.7% - Answers -may result in burst suppression
TIVA MoA on pt mvmnt - Answers -Glycine receptor blocking in the SC
Which is not a major MoA of the usual anesthetic agents that affect IONM? - Answers -
Inhibition of nerve conduction velocity
EP modality most affected by propofol - Answers -Mid-latency auditory response
Ketamine - Answers -(NMDA antagonist)
-does NOT act @ GABA synapse
-desirable for peds <6-10 y/o + TCeMEP monitoring
-agent that least depresses SSEPs
-SSEP/MEP = INC amp
-EEG = INC beta
Propofol - Answers -(GABA agonist)
-SSEP/BAER = INC latency
-EEG = slowing
Etomidate - Answers -(GABA agonist)
-SSEP/MEP: INC amp
-EEG: slowing
dexmeditomidine (Precedex) - Answers -(α2-adrenergic antagonist)
-mimics nml sleep; awakening --> most nml neuro exam
Cavities inside the skull - Answers -Anterior/middle/posterior fossa
Cranial bones - Answers -Frontal, occipital, sphenoid, ethmoid (unpaired). Parietal &
temporal (paired).
Mental protuberance - Answers -chin bone
MCA supply of the cerebral cortex - Answers -Hand + face/mouth/auditory
Cranial nerves - Answers --12 pairs (Mixed fibers: sensory/motor/both).
-Emerge @ irregular intervals from the brain.
-Nuclei displacement:
Motor = medial Sensory = lateral
Meckle's Cave - Answers -Depression in the medial middle fossa where CN V ganglion
sits
Low frequency sounds - Answers -@ apex of cochlea
Area of spine w/ small pedicles, long spinous process, large inter-vertebral foramen -
Answers -Thoracic
Neuroforamen - Answers -Opening w/in the spinal canal for nerve roots to enter the SC
Firm outer layer of the disc - Answers -Annulus fibrosis
Syrinx - Answers -Fluid-filled cavity @ center of the SC
Spinal cord ends @ the level btwn: - Answers -L1-L2 vertebrae (Conus Medullaris)
Blood supply to the SC consists of: - Answers -1 ASA for both MEP tracts
Hydrostatic pressure - Answers -Depends on body position
Structural functional anatomy may be altered by: - Answers -Previous lesions, current,
plasticity, pressure
Glia cell - Answers -Comes from the Greek word "glue"
Large diameter nerve fiber (vs. small diameter) - Answers --Recruited 1st w/ INC'd stim
intensity
-Higher conduction velocity
-More vulnerable to hypoxia & pressure Δ's
,Synaptic transmission, and/or Δ's in thalamocortical projections, produce - Answers -
Cortical potentials
Peripheral nerve sensitivity - Answers -Least sensitive to injury (more sensitive = SC
grey/white mater, cortical grey matter)
Cavernous angiomas - Answers -Multi-lobulated lesions containing hemorrhage
Geriatric population: prevalence of temporal bone hyperostosis - Answers -10-15%
Presbycusis - Answers -High freq hearing loss; gradually occurs in older individuals
Most commonly injured CN - Answers -Facial nerve (VII)
Burst fracture - Answers --Break in the vertebra
-Failure of anterior & middle vertebral columns
-Caused by violent compressive event (fall, MVA)
Excessive neck flexion in sitting position - Answers -Quadraparesis (due to ischemia in
upper T-spine)
Lhermittes Sign - Answers -Shocking sensation that occurs throughout the body during
neck flexion
Central Cord Syndrome (CCS) - Answers --Sacral sparing
-Loss of sensory/motor fx @ level of injury
-Disruption of grey matter
(+) Babinski Sign could indicate - Answers --severe [UMN] SC trauma
-abnml PTN SSEPs
Hoffman's Reflex (1918) - Answers -Palmar flexion of the thumb when the distal phalanx
of the middle finger (of the same hand) is rapidly stroked
A nml curve of the lumbar spine taking place @ 1-2 y/o - Answers -Kyphosis
Scoliosis progression in peds - Answers -More likely in girls > boys
Apraxia - Answers -Difficulty w/ skilled mvmnts
Neurapraxia - Answers -PNS disorder: blockage of sensory + motor nerve conduction
(w/o axonal damage)
INC venous pressure leads to - Answers --venous congestion; DEC drainage of nml
veins; chronic hypoxia
-NOT hypotension
, common source of air embolism introduction into the blood supply - Answers -Superior
sagittal sinus
MAC is approximated by the effect of anesthesia on - Answers -H-reflex (mvmnt when
stimulated)
Sevo/Des/N2O - Answers -DO NOT act on the same neuronal receptors
On an equi-MAC basis (w/ equivalent doses of anes), which has the greatest effect on
MEPs of recorded mm's? - Answers -N2O
N2O - Answers --synergistic IONM effects when mixed w/ Iso --> depressed IONM
-weak anesthetic agent
-causes ~75% DEC in SSEP amplitudes
Desflurane - Answers --affects NMJ --> enhances effect of NMBs
-no effect on MEP CMAPs
-eliminates most rapidly
Isoflurane 1.7% - Answers -may result in burst suppression
TIVA MoA on pt mvmnt - Answers -Glycine receptor blocking in the SC
Which is not a major MoA of the usual anesthetic agents that affect IONM? - Answers -
Inhibition of nerve conduction velocity
EP modality most affected by propofol - Answers -Mid-latency auditory response
Ketamine - Answers -(NMDA antagonist)
-does NOT act @ GABA synapse
-desirable for peds <6-10 y/o + TCeMEP monitoring
-agent that least depresses SSEPs
-SSEP/MEP = INC amp
-EEG = INC beta
Propofol - Answers -(GABA agonist)
-SSEP/BAER = INC latency
-EEG = slowing
Etomidate - Answers -(GABA agonist)
-SSEP/MEP: INC amp
-EEG: slowing
dexmeditomidine (Precedex) - Answers -(α2-adrenergic antagonist)
-mimics nml sleep; awakening --> most nml neuro exam
