Transcript UNIVERSITY OF TEXAS AT DALLAS SCHOOL OF BEHAVIORAL AND BRAIN SCIENCES

UNIVERSITY OF TEXAS
AT DALLAS
SCHOOL OF BEHAVIORAL AND BRAIN
SCIENCES
INTRAOPERATIVE
NEUROPHYSIOLOGIC
MONITORING CAN REDUCE
THE RISK OF IATROGENIC
INJURIES TO NERVOUS
TISSUE
We cannot cure all diseases but we
can at least do our best not to hurt
people while trying to cure them
Intraoperative neurophysiologic
monitoring
• Uses relatively standard neurophysiologic
techniques but it took some time to move
that to the operating room, a process that
is still ongoing
Intraoperative neurophysiologic
monitoring
• Before 1970: Sporadic in some, mostly
university hospitals
• 1970-1980: Systematic in a few university
hospitals
• 1980-1990: Systematic in increasing
number, mostly university hospitals
• 1990-2000: Spreading to all types of
hospitals
Before 1970:
Leonid Malis
Neurosurgeon
• Evoked potentials from the sensory cortex.
Facial nerve, visual evoked potentials etc.
• Stated later that microneurosurgery had
made intraoperative monitoring
unnecessary.
Before 1970
• Facial nerve monitoring:
– Rand RW, Kurze TL. (1965). Facial nerve
preservation by posterior fossa transmeatal
microdissection in total removal of acoustic
tumours. J Neurol Neurosurg Psychiat 28,
311-316.
– Hilger J. (1964). Facial nerve stimulator.
Trans Am Acad Ophth. Otolaryngol. 68, 74-76.
1970-1980:
Richard Brown
Physiologist
• Pioneered the use of electrophysiologic
techniques in the operating room
• Introduced recording of somatosensory
evoked potentials in scoliosis operations,
which reduced the incidence of severe
complications (paraplegia)
1980-1990:
Betty Grundy
Anesthesiologist
• Auditory evoked potentials (ABR)
• Reduced the incidence of hearing loss and
loss of hearing in operations in the
cerebello-pontine angle
1980-1990:
Betty Grundy
Anesthesiologist
• Grundy BL. (1983). Intraoperative
monitoring of sensory evoked potentials.
Anesthesiology 58, 72-87.
• Grundy BL. (1985). Evoked potentials
monitoring, in Blitt CD (ed): Monitoring in
Anesthesia and Critical Care Medicine.
New York: Churchill-Livingstone, pp.
345-4ll.
1980-1990
Auditory evoked potentials (ABR)
• Raudzens PA. (1982). Intraoperative monitoring
of evoked potentials. Ann NY Acad Sci 388,
308-326.
• Friedman WA, Kaplan BJ, Gravenstein D and
Rhoton AL. Intraoperative Brain-Stem Auditory
Evoked Potentials During Posterior Fossa
Microvascular Decompression. J. Neurosurg. 62:
552-557, 1985.
• Radtke R, Erwin W and Wilkins R. Intraoperative
Brainstem Auditory Evoked Potentials:
Significant Decrease in Post-Operative
Morbidity. Neurology: 187-191, 1989.
1980-1990
Direct recordings from the auditory nerve
• Møller AR and Jannetta PJ. Monitoring Auditory
Functions During Cranial Nerve Microvascular
Decompression Operations by Direct Recording from the
Eighth Nerve. J. Neurosurg. 59: 493-499, 1983.
• Silverstein H, Norrell H, Hyman S. Simultaneous use of
CO2 laser with continuous monitoring of eighth cranial
nerve action potential during acoustic neuroma surgery.
Otolaryngol Head Neck Surg. 92, 80-84,1984.
Bipolar
recording
from the
eighth
cranial
nerve
1980-1990
Laligam Sekhar
Neurosurgeon
Promoted intraoperative monitoring of
cranial nerves in skull base operations
Recording from extraocular
muscles:
Needle electrodes placed
percutaneously so they
come close to respective
muscles
• Medial rectus for CNIII
• Lateral rectus for CNVI
• Superior oblique for CNIV
1980-1990
Laligam Sekhar
Neurosurgeon
Sekhar, L.N. and Møller, A.R. Operative management of
tumors involving the cavernous sinus. J. Neurosurg. 64:
879-889, 1986. (Also published in Yearbook of Cancer,
1988.)
Møller, A.R. Electrophysiological monitoring of cranial
nerves in operations in the skull base. In: Tumors of the
Cranial Base: Diagnosis and Treatment, Chapter 7, pp.
123-132. L.N. Sekhar and V. Schramm, eds. Futura
Publishers, Inc., Mt. Kisco, New York, 1987.
1980-1990
Direct recordings from the cochlear nucleus
as an alternative to recordings from the
auditory nerve
• Møller AR, Jannetta PJ. Auditory evoked
potentials recorded from the cochlear
nucleus and its vicinity in man. J.
Neurosurg. 59, 1013-1018, (1983).
TUMOR
ELECTRODE
WIRE UNDER
DURA
SUTURES
CN VIII
CN IX & CN X
FLOCCULUS
FORAMEN
OF LUSCHKA
WICK
ELECTRODE
ELECTRODE
WIRE
CHOROID
PLEXUS
FROM: MOLLER ET AL 1994
1991-2000
VEDRAN DELETIS
Monitoring of motor systems
• How to stimulate?
– Magnetic or electric
• How to record?
– EMG or nerve recording
Recording of responses from
descending motor tracts
(D and I waves)
Recordings from the surface of the spinal cord in a 14 year old
patient Undergoing a scoliosis operation. Transcranial electrical
stimulation at different strengths (100%=750V at Cz and 6 cm
anterior)
From: Deletis and Shils
2002
Comparison between
transcranial and direct
stimulation of the
motor cortex
Deletis and Shils 2002
Muscle evoked
potentials elicited by
transcranial electrical
stimulation and
recorded from the
thenar muscle to
show influence of
stimulus parameters
From Neuloh and
Schramm 2002
2000-2005
RICHARD TOLEIKIS
Pedicle screw monitoring
provided information about cost
effectiveness of intraoperative
monitoring
Toleikis, J.R. 2002. Neurophysiological
monitoring during pedicle screw placement.
In: Deletis, V., Shils, J.L., (Eds.),
Neurophysiology in Neurosurgery. Elsevier,
Amsterdam. pp. 231-264.
2000-2005
TOD SLOAN
Effects of different anesthesia
regimen on motor evoked
potentials
EFFECT OF INCREASING DOSES OF ETOMIDATE ON
COMPOUND MUSCLE ACTION POTENTIAL IN RESPONSE
TO TRANSCRANIAL ELECTRICAL MOTOR CORTEX
STIMULATION
FROM SLOAN 2002
Summary: Intraoperative
neurophysiologic monitoring for
reducing the risk of iatrogenic
injuries to the nervous system
• Inexpensive and effective method for
detecting changes in function
• Real time or nearly real time monitoring of
function
• Imaging methods are difficult to use in the
operating room and provide only
information about structure
USE OF
ELECTROPHYSIOLOGIC
METHODS FOR GUIDANCE
OF SURGICAL PROCEDURES
1995-2005
LEO HAPPEL
Peripheral nerves
• Intraoperative diagnostics
• Guidance of repair
1990-2000
C. STRAUSS, N. MOROTA
Mapping of the floor of the
fourth ventricle
Providing safe entries to the
brainstem
Mapping of the brainstem cranial motor nuclei
From Morota et al 2002
1990-2000
Guidance of placement of
lesions and electrodes for
deep brain stimulation
• Thalamus for pain
• Basal ganglia for movement
disorders
INTRODUCTION OF A NEW
RECORDING TECHNIQUE IN
THE OPERATING ROOM
Recordings from single (or multi) units
based on work by Albe-Fessard and her
co-workers
1990-2005
J.L.Vitek, J. Shils, F. Lenz
Deep brain stimulation
• Placement of stimulating electrodes in
the thalamus for pain
• Placement of electrodes in the basal
ganglia for movement disorders
• Stereotactic techniques
• Electrophysiologic guidance
Artist’s rendition of the structure of the basal ganglia that are
targets for lesions and implantations of electrodes for deep brain
Stimulation.
(From Shils, J.L., Tagliati, M., Alterman, R.L. 2002. Neurophysiological monitoring
during neurosurgery for movement disorders. In: Deletis, V., Shils, J.L., (Eds.),
Neurophysiology in Neurosurgery. Academic Press, Amsterdam. pp. 405-448.)
Recordings of unit activity from three
different cells in the basal ganglia
Guidance of implantation of
electrodes on the cochlear
nucleus (brainstem implants)
for providing hearing in
individuals with injured
auditory nerve
Guidance of implantation of
stimulating electrodes in other
parts of the CNS
(Dorsal column, cerebral cortex)
For treatment of tinnitus and pain
Guidance in microvascular
decompression of the facial
nerve root for hemifacial
spasm
Monitoring of the abnormal
muscle response
OPERATIONS FOR HEMIFACIAL SPASM
Intraoperative
recordings of
abnormal muscle
response can help
the surgeon in
achieving the
therapeutical goal of
MVD operations for
hemifacial spasm
The abnormal muscle response disappears
when the offending vessel is moved off the
facial nerve
Practical advantages of studies of
hemifacial spasm
• The abnormal muscle response
disappears when the offending vessel is
moved off the facial nerve
• That helps find the offending vessel
• Make it possible to ensure that the
disorder is effectively treated before the
operation is ended
2000-2005
VEDRAN DELETIS
Introducing advanced
electrophysiological methods
into the operating room
• Collision techniques
2000-2005
VEDRAN DELETIS
Mapping of the corticospinal
tract of the spinal cord using
collision techniques
Mapping of the corticospinal tract using D-wave collision
(From: Deletis, V., Camargo, A.B. 2001. Interventional neurophysiological
mapping and monitoring during spinal cord procedures. Stereotact Funct
Neurosurg 77, 25-8.)
RESEARCH IN THE
OPERATING ROOM
Research in the neurosurgical
operating room
• Basic research
– Purpose: Gain new knowledge. No direct
expected benefit to patients
• Applied research
– Purpose: Improve treatment. Immediate or
long term benefit to patients
Why do research in the operating
room?
What are the advantages over research in
the traditional animal research laboratory?
• Humans are different from animals
• It is easier to study the physiology of
diseased systems in humans than trying to
make animal models of diseases
• Humans can respond and tell you how they
feel
The operating room is a goldmine
for physiologic studies
• Studies in animals can supplement studies
in the operating room
WILDER PENFIELD
1891 – 1976
Founder of the Montreal
Neurological Institute 1934
Penfield may be regarded as the
founder of intraoperative
neurophysiologic research
WILDER PENFIELD
Neurosurgeon
"Brain surgery is a terrible profession. If I
did not feel it will become different in my
lifetime, I should hate it." (1921)
• Solid background in neurophysiology, inspired by
Sherrington during a Rhodes Scholarship to Oxford
• Did ground breaking work in many areas. His work on
the somatosensory system is especially known
• In the 1950s he used electrical stimulation to find
epileptic foci
• Extensive studies of the temporal lobe, especially
memory
WILDER PENFIELD
Neurosurgeon
• Penfield W and Boldrey E. Somatic Motor and Sensory
Representation in the Cerebral Cortex of Man as Studied
by Electrical Stimulation. Brain 60: 389-443, 1937.
• Penfield W and Rasmussen T: The cerebral cortex of
man: a clinical study of localization of function, New
York, 1950, Macmillan.
Organization of the somatosensory cortex (homunculus)
After Penfield
Dr. Penfield at work
GEORGE A. OJEMANN
Neurosurgeon
Active in the Department of Neurological
Surgery, University of Washington
• Mapping of the temporal lobe during
epilepsy surgery
• Studies of centers for memory and speech
• Uses electrical current to inactivate
specific regions
GEORGE A. OJEMANN
Neurosurgeon
• Worked with Otto Creutzfeldt from
Germany to develop microelectrode
recordings from the brain of awake
patients.
• Studied neuronal activity during face
recognition.
GASTON CELESIA
Neurologist
• Recorded evoked responses directly from
the human auditory cortex
• Determined the exact latency of the
negative peak of these potentials (19.1 +/2.6 msec), which was important for the
identification of neural generators of scalp
recorded auditory evoked potentials.
GASTON CELESIA
Neurologist
• Celesia GG, Broughton RJ, Rasmussen T and
Branch C. Auditory Evoked Responses from the
Exposed Human Cortex. Electroenceph. Clin.
Neurophysiol. 24: 458-466, 1968.
• Celesia GG and Puletti F. Auditory Cortical
Areas of Man. Neurology 19: 211-220, 1969.
Neural generators of
somatosensory evoked potentials
Dorsal column and cerebral cortex
• Celesia GG. Somatosensory Evoked Potentials
Recorded Directly from Human Thalamus and Sm I
Cortical Area. Archives of Neurology 36: 399-405, 1979.
• Møller AR, Jannetta PJ and Jho HD. Recordings from
Human Dorsal Column Nuclei Using Stimulation of the
Lower Limb. Neurosurgery 26: 291-299, 1990.
Neural generators of auditory
evoked potentials
Auditory nerve
•
•
•
•
•
•
Isao Hashimoto, Japanese Neurosurgeon 1981
Aage Møller, Neurophysiologist 1981
J. P. Spire, Neurologist 1982
Hillary Pratt 1985
William Martin, Audiologist 1995
Conclusion: The auditory nerve is longer in man than in
the cat
Neural generators of brainstem
auditory evoked potentials
Cochlear nucleus and inferior colliculus
• Hashimoto I. Auditory Evoked Potentials from the
Humans Midbrain: Slow Brain Stem Responses.
Electroencephalography and Clinical Neurophysiology
53: 652 657, 1982.
• Møller AR and Jannetta PJ. Auditory Evoked Potentials
Recorded from the Cochlear Nucleus and Its Vicinity in
Man. J. Neurosurg. 59: 1013-1018, 1983.
• Møller AR and Jannetta PJ. Evoked Potentials from the
Inferior Colliculus in Man. Electroenceph. Clin.
Neurophysiol. 53: 612-620, 1982.
• Conclusion: Peak V is generated by the proximal lateral
lemniscus
Thalamus
Studies of pain
• The thalamus is the gateway for
– ascending sensory information
– descending motor activity
• The thalamus plays an important role in
processing of pain.
FRED LENZ
Neurosurgeon
Active in the Department of Neurosurgery
Director of Epilepsy Surgery, Johns Hopkins
• Studies of the thalamus in awake humans
using microelectrodes
• Map the thalamus with regard to
involvement in pain and response to
innocuous stimulation
FRED LENZ
Neurosurgeon
Studies of pain
• Lenz FA and Dougherty PM. Pain Processing in the
Ventrocaudal Nucleus of the Human Thalamus. In: Pain
and the Brain, edited by Bromm B and Desmedt JE.
New York: Raven Press, 1995, p. 175-185.
• Lenz FA, Lee JI, Garonzik IM, Rowland LH, Dougherty
PM and Hua SE. Plasticity of Pain-Related Neuronal
Activity in the Human Thalamus. Progr. Brain Res. 129:
253-273, 2000.
• Greenspan JD, Lee RR and Lenz FA. Pain Sensitivity
Alterations as a Function of Lesion Localization in the
Parasylvian Cortex. Pain 81: 273-282, 1999.
Studies of hyperactive disorders
Hemifacial spasm and tinnitus
• How can blood vessels in contact with the
root of a cranial sometimes cause signs of
hyperactivity?
• HFS: Intracranial studies indicate that the
anatomical location of the physiological
abnormality is central to the location of
vascular contact with the facial nerve
USE OF ANIMAL STUDIES FOR
SOLVING PROBLEMS RELATED
TO NEUROSURGERY
LINDSEY SYMON
Neurosurgeon
• Animal experiments with N.M.Branston,
determined how to use somatosensory
evoked potentials to estimate risk of
clamping major blood vessels
• These experiments provided information
about the safe clamping time in aneurysm
operations
HEMIFACIAL SPASM:
How can the facial motonucleus
become hyperactive from vascular
irritation of the facial nerve?
• Animal experiments supported the
hypothesis that abnormal stimulation of a
nucleus can over time lead to hyperactivity
(seizure)
• The kindling hypothesis (Goddard)
The role of expression of neural
plasticity in creating symptoms and
signs of disorders is not limited to
hemifacial spasm
• Neuropathic pain
• Tinnitus
• Facial synkinesis after pareses
There is no sharp border between
basic and applied research
• The method used for studies of neural
generators for the ABR came into use for
monitoring the auditory nerve
• Research on speech and language centers
in the brain has been important for epilepsy
operations
• Research on hemifacial spasm provided
better outcome of MVD operations
FUTURE
Prediction is very difficult,
especially about the future
Niels Bohr
However, I dare to predict that
the future of intraoperative
neurophysiologic monitoring is
bright!
CONSOLIDATION OF
EXISTING AREAS
• Education
• Spread of information about the benefits
from the use of monitoring
FUTURE
• Promote research in the operating room
• Do basic research that can help
understanding of the function of the
normal and diseased nervous system
• Do applied research that can help patients
in the short term
• Publish studies and document the benefit
of monitoring
FUTURE
• Promote teaching both of the practical
skills and of the physiologic and
anatomical basis for intraoperative
neurophysiologic monitoring
• Promote the use of intraoperative
monitoring in operations where it can
benefit the patient and the surgeon
• Study the efficacy of intraoperative
monitoring and the achieved reduction in
postoperative deficits and other benefits
FUTURE
Setting standards:
• Aim at reducing the risk of even smaller
postoperative deficits than those that can
be detected by standard tests
• Include reduction of loss of quality of life in
goals of intraoperative monitoring
FUTURE STANDARDS
Quality of life
• Quality of life may be reduced postoperatively
without any detectable deficits
– Nikolopoulos TP, Johnson I, O'Donoghue GM.
(1998). Quality of life after acoustic neuroma surgery.
Laryngoscope (L1W), Sep; 108 (9), 1382-1385.
Should we change our standards for
evaluating changes in electrophysiologic
data to reflect risk of reduction in quality
of life?
NEW AREAS FOR
MONITORING
• Guidance of placement of electrodes in
other areas of the brain and spinal cord
BE PROUD OF WHAT YOU ARE
DOING
• Neurophysiologic monitoring has saved
many people from severe neurologic deficits
as complications from surgical operations
• Reducing the risk of lifelong neurologic
deficits is a major achievement
• Contributions to better therapeutic results
and better operating technique are difficult to
evaluate