Surgery of the Human Cerebrum Part II, Medycyna, Neurochirurgia - podręczniki
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EDITOR’S LETTER
S
URGERY OF THE
H
UMAN
C
EREBRUM
II:
T
HE
B
ROADEST
C
ANVAS
rguably the broadest canvas for application of
the technical advances in the biological and
hard sciences is the human cerebrum.
Indeed, these opportunities for application have
been realized in areas that have been approached in
P
ART
II
of this three part series.
Advances in imaging, technical miniaturization,
and the computer have played an essential role in
changing our approaches to a wide spectrum of
disorders affecting the brain. Physical and biological
capabilities have offered new apertures to the
treatment of epilepsies, movement disorders, and
other functional problems. The amalgam of the
computer, imaging, and the sophisticated control of
high energy forms has offered a neurosurgical tool
called stereotactic radiosurgery, which already has
evolved through a number of phases of
advancement becoming an essential
feature of every truly modern
neurosurgical practice.
Endoscopy, through technical
improvement in application of physical
principles of prism physics and light
gathering capacity, coupled with
progressive miniaturization and fiber
optics have revolutionized ideas related
to intraventricular access and the
management of hydrocephalus as well as other
technical challenges.
Technical advances in valve construction and
design along with imaging capabilities have changed
elements of approaches to the composite of
hydrocephalic syndromes and etiologies.
A combination of these capabilities has modified
and enhanced our views concerning the
management of cerebral infections and infestations.
In short, during a single generation, technical
management capabilities and strategies have
undergone immense metamorphoses!
For
P
ART
II
OF
S
URGERY OF THE
H
UMAN
C
EREBRUM
, this remarkable evolution and what
might be termed the current "state of the art" is
discussed by a number of esteemed individuals and
coauthors:
1)
Epilepsy
- Johannes Schramm
2)
Infections and Infestations
- Walter A. Hall
3)
Endoscopy
- Paolo Cappabianca
4)
Pediatric Hydrocephalus
- James M. Drake
5)
Adult Hydrocephalus
- Marvin Bergsneider
6)
Stereotactic Radiosurgery
- Douglas Kondziolka
7)
Movement Disorders
- Ali R. Rezai
These papers are augmented by selected relevant
recent archival manuscripts and individual attendant
bibliographies from the Journal's publications over
the past decade.
No doubt, in considering a
retrospective view in the history of
medicine and especially neurological
surgery, this documentation of
current capability and strategy is
phenomenal - particularly considering
the developmental time frame!
This material and that presented in
P
ART
I
of this monumental supplement
will be augmented by an additional 30th
Anniversary offering with focus on the topics of
Psycho-affective Disorders and Pain
(Giovanni Broggi),
3D Microsurgical and Tractographic Anatomy of the
White Matter of the Human Brain
(Albert Rhoton, Jr.),
Intraventricular Tumors
(M. Gazi Yasargil),
Extra Axial
Lesions
(Peter Black),
Basal Lesions
(Madjid Samii),
Giant Aneurysms
(Robert Spetzler),
Revascularization
(Laligam Sekhar),
Endovascular Techniques
(L. Nelson
Hopkins), and
Advanced Methodologies
(Michael
Apuzzo) in
P
ART
III
- the final component of the
volume.
Michael L.J. Apuzzo
Los Angeles, California
Neurosurgery 62 [SHC Suppl 2]:SHC459, 2008
DOI: 10.1227/01.NEU.0000297092.02228.55
Number 8, 1949 by Jackson Pollock. Collection Neuberger
Museum of Art, Purchase College, State University of New
York, gift of Roy R. Neuberger, Jim Frank, photographer.
VOLUME 62 | NUMBER 2 | FEBRUARY 2008 SUPPLEMENT |
SHC459
A
EPILEPSY
T
HE
S
URGERY OF
E
PILEPSY
Johannes Schramm, M.D.
Department of Neurosurgery,
University of Bonn Medical Center,
Bonn, Germany
THE IDEA OF surgical treatment for epilepsy is not new. However, widespread use and
general acceptance of this treatment has only been achieved during the past three
decades. A crucial step in this direction was the development of video electroen-
cephalographic monitoring. Improvements in imaging resulted in an increased ability
for preoperative identification of intracerebral and potentially epileptogenic lesions.
High resolution magnetic resonance imaging plays a major role in structural and func-
tional imaging; other functional imaging techniques (e.g., positron emission tomogra-
phy and single-photon emission computed tomography) provide complementary data
and, together with corresponding electroencephalographic findings, result in a hypoth-
esis of the epileptogenic lesion, epileptogenic zone, and the functional deficit zone.
The development of microneurosurgical techniques was a prerequisite for the general
acceptance of elective intracranial surgery. New less invasive and safer resection tech-
niques have been developed, and new palliative and augmentative techniques have
been introduced. Today, epilepsy surgery is more effective and conveys a better seizure
control rate. It has become safer and less invasive, with lower morbidity and mortal-
ity rates. This article summarizes the various developments of the past three decades
and describes the present tools for presurgical evaluation and surgical strategy, as well
as ideas and future perspectives for epilepsy surgery.
KEY WORDS:
Electroencephalographic monitoring, Epilepsy, Epileptogenic lesion, Seizure control, Surgery
Hans Clusmann, M.D.
Department of Neurosurgery,
University of Bonn Medical Center,
Bonn, Germany
Reprint requests:
Hans Clusmann, M.D.,
Department of Neurosurgery,
University of Bonn Medical Center,
Sigmund Freud Straße 25,
52105 Bonn, Germany.
Email: hans.clusmann@ukb.uni-bonn.de
Received,
May 4, 2007.
Accepted,
October 25, 2007.
Neurosurgery 62[SHC Suppl 2]:SHC463–SHC481, 2008
DOI: 10.1227/01.NEU.0000297106.65002.1F
CONCEPTS FOR EPILEPSY SURGERY
were first implanted by Jean Bancaud (7) and Jean Talairach
(176) in France. The first chronic depth electrode recording and
EEG telemetry were realized by Paul H. Crandall (42, 107).
This has been the setup for the development of epilepsy sur-
gery in the last 30 years.
(1857–1916) in London were the first to localize and
remove epileptogenic lesions, as identified by their
symptomatogenic zone, according to the pioneering work of
John Hughlings Jackson (1835–1911). Additional developments
were made in Germany by the neurosurgeons Fedor Krause
(1857–1937) and Otfried Foerster (1873–1941). Human scalp
electroencephalography (EEG) was first described in 1929 by
Hans Berger (11), who revolutionized epilepsy diagnosis
within 10 years with a hypothesis on the irritative and ictal
onset zones (152). Herbert Jasper (1941) described the EEG
characteristics of psychomotor seizures. This knowledge con-
tributed to the first temporal lobe resection for epilepsy in 1936
by Wilder Penfield. The first purely EEG-directed temporal
lobe resections were performed in Boston in 1947 by Percival
Bailey (1892–1973) with the neurophysiologist Frederick Gibbs
(1903–1992). Electroclinical monitoring of patients with
epilepsy, including the institution of simultaneous clinical and
EEG observations and chronic intracranial EEG recordings, was
established in the 1940s in a few specialized centers, first in the
Montreal Neurological Institute. Stereotactic depth electrodes
Developments since the 1970s
With the advent of positron emission tomography (PET) in
the late 1970s, and even more with magnetic resonance imag-
ing (MRI) in the 1980s, worldwide interest in epilepsy surgery
increased, enabled by the preoperative identification of intrac-
erebral and, potentially, epileptogenic lesions (21, 22, 41, 79,
99). Thus, new imaging methods increasingly eliminated the
uncertainty among preoperatively known clinical syndromes,
preoperative EEGs, and the intraoperative findings, as well as
the postoperative histological results. The more lesion-directed
approach (MRI) and the complementary information provided
by functional imaging techniques (PET and single-photon
emission computed tomography [SPECT]) resulted in identifi-
cation of epileptogenic lesions and functional deficit zones
(152). Developments were supported further by the parallel
advent of effective digital video techniques and data storage.
During the past 30 years, four developments have occurred
in parallel, albeit not in perfect synchrony: 1) the advent of
N
EUROSURGERY
VOLUME 62 | NUMBER 2 | FEBRUARY 2008 SUPPLEMENT |
SHC463
Historical Development before the 1970s
W
illiam MacEwen (1848–1924) and Victor Horsley
S
CHRAMM AND
C
LUSMANN
microneurosurgery, 2) the associated improvements in outcome
leading to a general acceptance of neurosurgery performed as
elective surgery, 3) development of new concepts of areas
involved or associated with epileptogenicity, and 4) simultane-
ous surface and depth recording with stereo-EEG providing
more detailed facts about the distribution and spread of epilep-
tic activity (7, 42, 177, 194, 205).
A
Recent Evolution and Progress: New Concepts
As mentioned previously, former work resulted in a theory
of different zones involved in the epilepsies. Despite some def-
inition differences, these concepts turned out to be important
because they are the fundaments of applying multiple diagnos-
tic means to approach the “epileptogenic zone” (134, 152, 194).
Six cortical zones that are considered at present in the presur-
gical evaluation of candidates for epilepsy surgery are: the
symptomatogenic zone, the irritative zone, the seizure-onset
zone, the epileptogenic lesion, the epileptogenic zone, and the
eloquent cortex. Rosenow and Lüders (152) reviewed the step-
wise historical evolution of these different zones. Different
diagnostic techniques are used in the definition of these corti-
cal zones such as video-EEG monitoring, MRI, ictal SPECT,
and PET. Established diagnostic tests have to be set apart from
procedures that should still be regarded as “experimental” such
as magnetoencephalography (MEG), dipole-source localization,
and spike-triggered functional MRI, although improvements in
these noninvasive techniques may lead to a more direct defini-
tion of the epileptogenic zone (152).
The epileptogenic zone is defined as a cortical area that is
inevitably necessary for the generation of clinical epileptic
seizures (152). This concept can only be proven by a circum-
scribed cortical resection leading to seizure freedom. In clinical
practice, the concept of an epileptogenic zone is a multidimen-
sional localization hypothesis, applying all available clinical
and technical diagnostic tools, however, never gaining absolute
certainty (108).
B
New Diagnostic Techniques
In the field of presurgical evaluation, which is thought to be
most crucial for failure or success after epilepsy surgery, intro-
duction of MRI played a major role. However, in its early days,
MRI was directed exclusively to the identification of morpho-
logical changes, i.e., the identification of a lesion, which is
known as an “epileptogenic lesion.” This was a tremendous
step forward, because it enabled noninvasive screening of the
brain for structural abnormalities with a sensitivity that
increased over the years. It is obvious that not everything
abnormal that we see has to do with the patient’s epilepsy. It is
standard practice to identify mesial temporal sclerosis on tem-
poral angulated MRI scans, especially in the coronal plane,
even without the application of more sophisticated algorithms
like magnetic resonance relaxometry or hippocampal volume-
try (
Fig. 1
) (181). Moreover, new and specific information can be
derived on the nature of cortical dysplasias. Whereas even 10
years ago most types of malformations of cortical development
remained speculative using MRI, with high numbers of misin-
FIGURE 1.
A
, upper panel
, T2-weighted
images acquired in the mid-1990s in stan-
dard angulation showing some hippocam-
pal atrophy on the left side;
middle
panel
, fluid-attenuated inversion recov-
ery (FLAIR) and T2-weighted images of
the same patient obtained some time later
with temporal angulation suggesting not
only atrophy, but also hippocampal sclero-
sis;
lower panel
, recent FLAIR and T2-
weighted images of other patients in
whom even mild hippocampal signal
changes can be detected, even in the ab-
sence of severe hippocampal atrophy.
B
,
coronal magnetic resonance imaging (MRI) scans were acquired in tempo-
ral angulation, illustrating the present standard of detecting mesial tem-
poral sclerosis with a 3-T MRI scanner.
C
,
schematic drawing showing
standard (
dotted line
) versus temporal (
straight line
) MRI angulation.
C
SHC464
| VOLUME 62 | NUMBER 2 | FEBRUARY 2008 SUPPLEMENT
www.neurosurgery-online.com
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