Hindawi Publishing Corporation
Epilepsy Research and Treatment
Volume 2012, Article ID 382095, 8 pages
doi:10.1155/2012/382095
Review Article
Selective Amygdalohippocampectomy
David Spencer1 and Kim Burchiel2
1 Department
2 Department
of Neurology, Oregon Health & Science University, Portland, OR 9739, USA
of Neurological Surgery, Oregon Health & Science University, Portland, OR 97239, USA
Correspondence should be addressed to David Spencer, spencerd@ohsu.edu
Received 8 November 2010; Revised 22 February 2011; Accepted 25 March 2011
Academic Editor: Seyed M. Mirsattari
Copyright © 2012 D. Spencer and K. Burchiel. This is an open access article distributed under the Creative Commons Attribution
License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly
cited.
Epilepsy surgery can be an effective epilepsy treatment for patients whose seizures do not respond to best medical therapy. For
patients with temporal lobe epilepsy, selective amygdalohippocampectomy (SAH) has emerged as a viable alternative to standard
anterior temporal lobectomy. This paper reviews the indications for SAH, the technical advances that have led to greater adoption
of the procedure, the expectations for seizure control, and the risks of morbidity.
1. Introduction
Epilepsy is a common condition that affects nearly 1%
of the world’s population. The World Health Organization
reports that neurological disease outranks HIV, cancer, and
coronary artery disease in years of life lost to disability, and
among neurological conditions, epilepsy ranks 4th [1]. While
nearly 2/3 of patients with epilepsy achieve good control of
seizures using antiepileptic medications, the remaining 1/3
have seizures that are resistant to medications and may be
considered as candidates for epilepsy surgery. The benefit
of epilepsy surgery in treatment-resistant epilepsy has been
demonstrated in numerous case series as well as by a recent
randomized clinical trial which demonstrated that surgery
is clearly superior to best medical therapy in patients with
temporal lobe epilepsy (TLE) [2].
Most people with TLE have seizures that originate from
the mesial-basal temporal lobe structures, including the
hippocampus, amygdala, and parahippocampal gyrus. The
traditional surgical approach has been en bloc anterior
temporal lobectomy (ATL). In this procedure, approximately
3–6 cm of anterior temporal neocortex is resected (depending on hemispheric language dominance), permitting access
to resection of mesial structures. A modification popularized
by the Yale group limits neocortical resection to 3.5 cm from
the temporal pole and spares the superior temporal gyrus,
obviating the need for language mapping in most cases [3, 4].
ATL offers advantages of good surgical exposure to allow
complete resection of mesial structures, relatively low morbidity, and permits pathological examination of en bloc specimens. This procedure is still commonly employed today.
The central epileptogenic role of mesial temporal structures in TLE has been demonstrated in animal models of
TLE and in pathological, electrophysiological, and structural and functional imaging studies. Thus, more targeted
mesial temporal resections that spared temporal neocortex
(selective amygdalohippocampectomy) were envisioned as
possible means of providing equivalent seizure control with
fewer neuropsychological sequelae (Figure 1).
2. Historical Background
Paulo Niemeyer reported selective resection of mesial temporal structures for intractable epilepsy in 1958 [5]. In a
letter to his colleague Henri Gastaut, he related “because the
focus of this epilepsy is usually in the nucleus amygdalae, in
Ammon’s horn, or in the hippocampus of gyrus, I resected
these 3 structures via a transventricular approach, almost
without touching the temporal cortex” [6]. The fascinating
history of his pioneering work in neurosurgery in Brazil is
related in a recent historical article by Cavalcanti et al. [6]. It
is notable that the procedure was developed well in advance
of the advent of image-guided neuronavigation systems.
Subsequently Wieser and Yasargil popularized a transsylvian
2
Epilepsy Research and Treatment
Anterior temporal lobectomy
Amygdalohippocampectomy
Figure 1: Comparison of anterior temporal lobectomy and selective amygdalohippocampectomy.
approach to SAH and reported outcomes of large numbers
of patients who underwent this procedure [7, 8]. Other
approaches including subtemporal [9] and variants of the
transcortical approach have been described [10, 11]. Use
of SAH became more widespread in the 1990s in tandem
with increased utilization of intraoperative neuronavigation
systems.
3. Indications
Selective amygdalohippocampectomy is employed in cases
of medically refractory temporal lobe epilepsy of mesial
temporal origin. There is no universally agreed upon definition of medically refractory or treatment-resistant epilepsy.
Many authorities use a working definition of failure of
at least two trials of antiepileptic drug monotherapy and
one combination therapy when used at therapeutic levels
over 1-2 years; however, a variety of definitions have been
employed [12, 13]. In practice, many patients have failed
much more extensive medication trials over much more
extended time periods.
Most commonly, suitable candidates are selected based
on convergent lines of evidence implicating unilateral mesial
temporal structures as the epileptogenic region [14]. Central to this decision is a compatible ictal semiology and
neurological history. Video-EEG monitoring should confirm
ictal semiology and stereotyped ictal onset on scalp EEG
consistent with mesial temporal origin. Interictal EEG may
show concordant unilateral or bilateral (usually ipsilateral
predominant) epileptiform discharges. MRI often demonstrates an abnormality in the mesial temporal structures:
most commonly hippocampal atrophy with or without
mesial temporal signal change on T2-weighted or FLAIR
sequences. Patients with exclusively mesial temporal foreign
tissue lesions (e.g., low grade tumor) or neurodevelopmental
abnormalities may also be good candidates for this procedure.
For patients in whom these lines of evidence fail to
converge or for whom some data points are lacking (e.g.,
absence of MRI lesion, poorly localized ictal onsets on
EEG), additional studies may be required, including PET,
MEG, or Ictal SPECT. Particularly in nonlesional cases, if
standard evaluation supplemented by specialized imaging
studies defines a unilateral temporal lobe onset, intracranial
EEG monitoring may be required to distinguish mesial from
temporal neocortical onset and determine whether selective
amygdalohippocampectomy is appropriate. Experience has
shown that surgical failure rates are higher if strict criteria for unilateral mesial temporal onset are not applied
[15].
Epilepsy Research and Treatment
Occasional patients with well-defined mesial temporal onset seizures should be excluded from consideration
for SAH. These include most patients with documented
independent bitemporal onset seizures [15] and those at
risk for severe global memory impairment as a result of
surgery. Patients with dominant temporal lobe foci are at
greatest risk for postoperative functional decline in verbal
memory, especially patients with high preoperative verbal
memory performance, normal hippocampal volume, and
later onset of seizures in adulthood [16]. Patients with a
similar pattern in the nondominant temporal lobe can also
experience clinically important deficits, but these are usually
less prominent than in dominant temporal lobe resections
[16]. While not always contraindications for surgery, this
is important information that must be weighed carefully
in presurgical decision making. Finally, patients with severe
bilateral hippocampal atrophy who fail to demonstrate
support of memory function contralateral to the proposed
surgical side on intracarotid amytal procedure (Wada test)
may be at risk for disabling global memory impairment,
although there are few documented cases [17–19]. Clearly
patients with idiopathic (primary) generalized epilepsies,
extratemporal focal epilepsy, and temporal neocortical foci
or temporal lobe epilepsy not clearly localized to mesial
temporal structures are not candidates for SAH. Patients
with exclusively psychogenic nonepileptic seizures (PNES)
are not candidates; those with concurrent PNES and mTLE
must be assessed very carefully, but the presence of PNES
should not exclude patients a priori [20].
4. Surgical Procedure
Here we describe in detail the commonly employed transcortical approach to SAH via the middle temporal gyrus. This
is the preferred procedure at our center; however, alternative
approaches including transsylvian and subtemporal methods
are also commonly employed and will also be briefly
discussed.
The procedure is accomplished with the assistance of
an image-based frameless intraoperative guidance system
(Figure 2). An MRI with placement of fiducial markers is
performed just prior to surgery. The procedure is performed
under routine general anesthesia with endotracheal intubation.
In the operating room, the patient is positioned supine
with the head held in position in 3-pin fixation, rotated 90
degrees to the opposite side, and parallel to the floor.
Following registration of scalp fiducials, the planned
entry point is marked on the scalp and the scalp is prepared
by infiltration with lidocaine, bupivacaine, and epinephrine.
After scalp and temporalis fascia incision and retraction,
the neuronavigation system is used to locate the temporal
craniotomy. Craniotomy is performed and dura opened and
flapped inferiorly. The neuronavigation system is used to
identify the location of the cortical incision in the middle
temporal gyrus that is 2.5–3.0 cm behind the tip of the temporal lobe and in an area free of cortical vessels (Figures 2 and
3). The corticectomy is generally 2–2.5 cm in length. Guided
by neuronavigation, dissection is performed toward the
3
Axial
A
L
R
P
Figure 2: Intraoperative neuronavigation showing the entry point
(lateral open circle), trajectory (yellow line), and target (medial
open circle).
temporal horn until the temporal horn is entered (Figure 3).
Two self-retaining brain retractors are placed to provide
an optimal view of the intraventricular anatomy, and key
anatomical structures are identified. The parahippocampal
gyrus is resected beginning with subpial resection of the
uncus and then advancing medially and posteriorly, with
frequent confirmation of location using neuronavigation and
care to preserve the mesial pial border. With resection of
the anterior uncus, the incisura is visualized, and superiorly
the internal carotid artery and third nerve can be seen
through the pia. The choroidal fissure is identified. Care
must be taken to insure that the dissection is not carried
superior to the choroidal fissure. The hippocampus is
then mobilized laterally and resected beginning anteriorly,
with care to preserve the anterior choroidal artery, and
carried posteriorly to the level of the tectal plate. Once the
hippocampal resection is completed, the cerebral peduncle
and anterior choroidal artery are visualized through the pia.
Neuronavigation is used to confirm the completeness of the
resection, and careful hemostasis is obtained.
In stepwise fashion the dura is closed, bone flap plated,
temporalis muscle reapproximated, and scalp closed in
layers to the skin. A postoperative neurological exam and
head CT are performed, and care is taken to continue
antiepileptic medications. Following overnight observation
in a neurological intensive care unit, the patient completes a
typically 3-4-day postoperative hospital stay before discharge
to home.
Several alternatives to this middle temporal gyrus
transcortical approach have been used. A minor variation with approach via the superior temporal sulcus was
employed at the Montreal Neurological Institute [10].
Wieser and Yasargil [8] popularized a transsylvian
approach and reported a large number of patients treated
with this approach. The transsylvian approach avoids injury
to the temporal neocortex and underlying white matter that
is traversed in the transcortical approach and allows en
bloc resections of the mesial temporal structures. However,
it is generally regarded as being more technically difficult,
allows limited surgical exposure, results in transaction of
the temporal stem, and poses a greater potential risk of
4
Epilepsy Research and Treatment
Figure 3: Transcortical amygdalohippocampectomy: position of craniotomy, position of cortical incision, surgical trajectory.
vascular injury or vasospasm [21], though this has rarely
been reported in large surgical series [22].
A subtemporal approach has also been advocated [9, 23].
This largely avoids injury to Meyer’s loop and resultant visual
field defects that can occur with other approaches. There
have been reports of fewer neuropsychological sequelae, but
data are limited [24, 25]. This strategy carries disadvantages
of potentially requiring excessive retraction of the temporal
lobe, possible injury to the vein of Labbe, and may require
removal of the zygomatic process.
5. Seizure Outcome
The ability of SAH to render patients seizure-free has been
reported extensively in case series [15, 26–28], nonrandomized comparator trials with ATL [29–36], and comparator
studies with historical controls [37].
Many centers exclusively employ one technique (ATL or
SAH), making comparisons difficult. The existing nonrandomized comparator trials have a variety of methodological concerns, including comparison of noncontemporary
groups as one procedure (ATL) was abandoned in favor
of another (SAH), substantial risk of selection bias since
patients were not randomized to procedure, and different
neurosurgeons performing each procedure, or procedures
being performed at different centers.
Overall, few differences in seizure-free outcomes based
on choice of surgical procedure (ATL, SAH) have been
demonstrated. Arruda and coworkers provided one of the
earliest comparator trials of ATL and SAH [30]. They
reported 74 patients, 37 of whom underwent each procedure. The groups were not randomized; however, different
neurosurgeons preferred each procedure and selection of
patients did not appear to be biased by clinical features. Both
groups had equivalent seizure-free rates, and they concluded
that the choice of procedure did not determine outcome;
seizure freedom was better predicted by preoperative imaging findings and underlying pathology. More recent larger
series have largely supported this conclusion. Clusmann et al.
reported 321 patients with TLE who underwent surgery,
including ATL and SAH, and concluded that seizure outcome
mainly correlated with diagnosis and clinical factors rather
than resection type, and reaffirmed the strong correlation of
MRI findings and underlying pathology with outcome [32].
Paglioli et al. compared a large non-contemporaneous group
of 80 patients who underwent ATL and 81 who were treated
with SAH with a mean followup of 5.8 years [34]. There
were no significant group differences in outcome, except
that fewer patients undergoing SAH were left with isolated
auras. An early study by Mackenzie and coworkers was the
exception: this study showed poorer outcomes following
SAH [31]. Closer examination of patient selection reveals
probable substantial selection bias. Patients with concordant
findings on noninvasive evaluations underwent ATL, while
SAH was performed only in a subset of more complex cases
that underwent intracranial monitoring and that were more
likely to have normal MRI findings.
Abosch and coworkers reported factors that might be
predictive of failure to control seizures with SAH [15].
Many of the signs predictive of higher risk of surgical
failure following SAH (bitemporal EEG findings, normal
hippocampal volumes, use of intracranial monitoring) are
not unique to this procedure and also predict lower success
rates following ATL. In fact, those who underwent a second
resection to extend the initial selective procedure largely
continued to fare poorly [15].
There is little evidence to suggest that different approaches to SAH result in different seizure-free outcomes [38].
There are some small reports suggesting that seizurefree outcomes following SAH are less robust in children
compared with adults [39, 40].
6. Neuropsychological Outcome
Neuropsychological outcome following SAH has been extensively reported in the literature. Often, the approach has
been to report change scores before and after SAH [16, 41–
43]. In some cases, attempts were made to compare to
Epilepsy Research and Treatment
cognitive outcomes following the “gold standard” procedure:
ATL [19, 29, 32–34, 36, 44, 45]. Most of these direct
comparator trials share similar methodological concerns
with the seizure outcome comparator trials discussed above
(noncontemporary cohorts, risk of selection bias, etc.).
Further complexity is introduced by the nonuniform choice
of cognitive assessments. Some studies focused on measures
specifically targeted at anticipated deficits (e.g., verbal memory tests), others used extensive batteries of tests that run
the risk of type I error, while others used general measures
that may be insensitive to changes caused by surgery (e.g.,
IQ scores). It is important to keep in mind that an absence
of demonstrated superior cognitive outcomes with the more
selective procedure does not mean that it does not produce
cognitive sparing; an alternative explanation is that the
cognitive tests may be too insensitive to detect differences.
Recent work has identified some previously unrecognized
language areas in anterior temporal neocortex that could be
at risk with a standard ATL procedure [46, 47], though the
extent of functional sparing following SAH has been debated
[48].
Many studies reported superiority of SAH compared
with ATL in some aspects of postoperative cognitive performance [7, 8, 32, 49–51], but some showed substantially
mixed findings or lack of superiority of more limited
resection [36, 44, 52, 53]. Most of these studies still recognize
the potential for meaningful cognitive declines following
the more selective procedure, although there are exceptions
[50, 54].
Some of the largest and most careful studies of cognitive
outcome following SAH have come from the group in Bonn,
Germany. Gleissner reported first 3-month and then 1-year
findings in 140 patients who underwent SAH [16, 42]. They
noted that the more selective procedure can have important
cognitive consequences: at the 3-month time point, nearly
half of the left SAH patients showed substantial loss of
verbal memory; functional declines were less common with
right-sided operations. Of the 115 who were studied at one
year, there was no substantial recovery of verbal memory
from the earlier time point. Preoperative performance was
the primary predictor of postoperative performance at 1
year. Paglioli and coworkers’ study of 80 patients who
underwent ATL and 81 submitted to SAH (nonrandomized,
noncontemporaneous) similarly found that patients who
underwent either procedure were at risk of verbal memory
decline if surgery was carried out in the dominant temporal
lobe; however, a greater proportion of left SAH patients
had improved verbal memory after surgery compared with
the left ATL procedure [34]. The large study of Clusmann
reported better outcome following SAH for attention, verbal
memory, and a composite of total neuropsychological performance [32]. Tanriverdi and coworkers compared a large
number of SAH (n = 133) and ATL (n = 123) patients,
found mixed cognitive results, and concluded that, although
both surgeries are effective, they both have the potential to
cause cognitive deficits [36].
Although accumulated evidence reviewed above suggests
a potential cognitive benefit of the more selective procedure
(SAH), it also provides ample evidence that the more
5
selective approach does not obviate the need for careful
preoperative cognitive assessment, particularly with respect
to risk of verbal memory worsening following dominant
temporal lobe SAH. An important conclusion from a large
series reporting neuropsychological outcomes following
SAH was “Our data clearly show that this does not mean no
or only very mild memory declines after SAH” [42]. Much
as with ATL, the risk to verbal memory probably depends
largely on the functional adequacy of the resected tissue, the
cognitive reserve (perhaps related in part to age and duration
of epilepsy), and the success in obtaining seizure freedom.
There have been some attempts to discern differential
cognitive outcomes with different SAH surgical approaches
[24, 25, 27, 38]. In theory, transcortical SAH can disrupt
and disconnect fiber tracts, as demonstrated on diffusion
tensor imaging by studying the path of a “virtual SAH”
[55]. However, in most reports, methodological concerns
and small numbers of patients limit the conclusions that can
be drawn. The report of Lutz et al. is an exception [38]. This
is a relatively large (N = 140) randomized prospective trial
of transsylvian versus transcortical SAH in a uniform population of patients with presumed mesial temporal sclerosis.
Few differences were found in the proportions of patients
in each group with neuropsychological improvement or
worsening on postoperative neuropsychological tests, and
left-sided surgeries resulted in worsening of verbal memory
regardless of approach. The exception was word fluency,
which improved in the transcortical but not transsylvian
group.
7. Surgical Complications
The visual field deficits seen following ATL can also be seen
with SAH, depending on the surgical approach, though they
may be less severe following the more selective procedure [56,
57].
Potential complications include the following:
(i) hemorrhage,
(ii) infarction (commonly of deep penetrating vessels
leading to lacunar stroke),
(iii) infection,
(iv) incomplete resection,
(v) variable contralateral homonymous superior quadrant visual field defect from injury to Meyer’s loop
(usually asymptomatic),
(vi) memory impairment,
(vii) transient dysnomia,
(viii) mood changes.
Strict adherence to time out procedures, careful patient
positioning, and careful visual identification of landmarks
and repeated reconfirmation of stereotactic findings can
minimize intraoperative complications. Detailed knowledge
of the mesial temporal anatomy is critical, and such understanding will avoid the potential perils of overreliance on
imagingbased neuronavigation systems. Attention to careful
6
patient selection and preoperative testing can minimize risk
to memory and risk of mood disturbances and can maximize
efficacy by excluding inappropriate patients.
Epilepsy Research and Treatment
[11]
8. Conclusions
Selective amygdalohippocampectomy has emerged as a
viable alternative to standard anterior temporal lobectomy
in patients with refractory TLE of mesial temporal origin.
Success rates are highest if strict criteria are employed to
determine suitable candidates. Progress in surgical technology including image-guided stereotactic surgery has made
SAH more accessible and effective. In carefully selected
candidates, seizure-free outcomes following SAH are comparable to ATL. While attention needs to be paid to risk of
neuropsychological morbidity, particularly with respect to
verbal memory, most studies suggest that there is benefit
to sparing temporal neocortex in the surgical treatment of
mTLE.
[12]
[13]
[14]
[15]
[16]
Acknowledgment
The authors would like to thank Andy Rekito for permission
to use the illustrations included in this paper.
References
[1] World Health Organization, Neurological Disorders: Public
Health Challenges, WHO Press, Geneva, Switzerland, 2006.
[2] S. Wiebe, W. T. Blume, J. P. Girvin, and M. Eliasziw, “A
randomized, controlled trial of surgery for temporal-lobe
epilepsy,” New England Journal of Medicine, vol. 345, no. 5, pp.
311–318, 2001.
[3] D. D. Spencer, S. S. Spencer, and R. H. Mattson, “Access to
the posterior medial temporal lobe structures in the surgical
treatment of temporal lobe epilepsy,” Neurosurgery, vol. 15, no.
5, pp. 667–671, 1984.
[4] D. D. I. J. Spencer, “Temporal lobectomy,” in Epilepsy Surgery,
H. Luders, Ed., pp. 533–545, Raven Press, New York, NY, USA,
1991.
[5] P.
Niemeyer,
“The
transventricular
amygdalahippocampectomy in temporal lobe epilepsy,” in Temporal
Lobe Epilepsy, M. Baldwin and P. Bailey, Eds., pp. 461–482,
Charles Thomas, Springfield, Mass, USA, 1958.
[6] D. D. Cavalcanti, J. A. D. Guasti, and M. C. Preul, “Neurological and architectural sinuosities: the niemeyer brothers,”
Neurosurgery, vol. 67, no. 5, pp. 1167–1179, 2010.
[7] H. G. Wieser and M. G. Yasargil, “Selective amygdalohippocampectomy as a surgical treatment of mesiobasal limbic
epilepsy,” Surgical Neurology, vol. 17, no. 6, pp. 445–457, 1982.
[8] M. G. Yaşargil, H. G. Wieser, A. Valavanis, K. von Ammon,
and P. Roth, “Surgery and results of selective amygdalahippocampectomy in one hundred patients with nonlesional
limbic epilepsy,” Neurosurgery Clinics of North America, vol. 4,
no. 2, pp. 243–261, 1993.
[9] T. S. Park, B. F. D. Bourgeois, D. L. Silbergeld, and W. E.
Dodson, “Subtemporal transparahippocampal amygdalohippocampectomy for surgical treatment of mesial temporal lobe
epilepsy: technical note,” Journal of Neurosurgery, vol. 85, no.
6, pp. 1172–1176, 1996.
[10] A. Olivier, “Relevance of removal of limbic structures in
surgery for temporal lobe epilepsy,” Canadian Journal of
[17]
[18]
[19]
[20]
[21]
[22]
[23]
[24]
[25]
[26]
Neurological Sciences, vol. 18, no. 4, supplement, pp. 628–635,
1991.
A. S. Little, K. A. Smith, K. Kirlin et al., “Modifications to
the subtemporal selective amygdalohippocampectomy using
a minimal-access technique: seizure and neuropsychological
outcomes,” Journal of Neurosurgery, vol. 111, no. 6, pp. 1263–
1274, 2009.
P. Kwan and M. J. Brodie, “Early identification of refractory
epilepsy,” New England Journal of Medicine, vol. 342, no. 5, pp.
314–319, 2000.
A. T. Berg and M. M. Kelly, “Defining intractability: comparisons among published definitions,” Epilepsia, vol. 47, no. 2,
pp. 431–436, 2006.
J. S. Duncan, “Epilepsy surgery,” Clinical Medicine, Journal of
the Royal College of Physicians of London, vol. 7, no. 2, pp. 137–
142, 2007.
A. Abosch, N. Bernasconi, W. Boling et al., “Factors predictive
of suboptimal seizure control following selective amygdalohippocampectomy,” Journal of Neurosurgery, vol. 97, no. 5, pp.
1142–1151, 2002.
U. Gleissner, C. Helmstaedter, J. Schramm, and C. E. Elger,
“Memory outcome after selective amygdalohippocampectomy: a study in 140 patients with temporal lobe epilepsy,”
Epilepsia, vol. 43, no. 1, pp. 87–95, 2002.
D. W. Loring, G. P. Lee, K. J. Meador et al., “The intracarotid
amobarbital procedure as a predictor of memory failure
following unilateral temporal lobectomy,” Neurology, vol. 40,
no. 4, pp. 605–610, 1990.
J. N. Acharya and D. S. Dinner, “Use of the intracarotid
amobarbital procedure in the evaluation of memory,” Journal
of Clinical Neurophysiology, vol. 14, no. 4, pp. 311–325, 1997.
M. E. Lacruz, G. Alarcón, N. Akanuma et al., “Neuropsychological effects associated with temporal lobectomy and
amygdalohippocampectomy depending on Wada test failure,”
Journal of Neurology, Neurosurgery and Psychiatry, vol. 75, no.
4, pp. 600–607, 2004.
M. Reuber, M. Kurthen, G. Fernández, J. Schramm, and
C. E. Elger, “Epilepsy surgery in patients with additional
psychogenic seizures,” Archives of Neurology, vol. 59, no. 1, pp.
82–86, 2002.
C. Schaller, A. Jung, H. Clusmann, J. Schramm, and B.
Meyer, “Rate of vasospasm following the transsylvian versus
transcortical approach for selective amygdalohippocampectomy,” Neurological Research, vol. 26, no. 6, pp. 666–670, 2004.
M. G. Yaşargil, N. Krayenbühl, P. Roth, S. P. C. Hsu, and
D. C. H. Yaşargil, “The selective amygdalohippocampectomy
for intractable temporal limbic seizures: historical vignette,”
Journal of Neurosurgery, vol. 112, no. 1, pp. 168–185, 2010.
T. Hori, S. Tabuchi, M. Kurosaki et al., “Subtemporal
amygdalohippocampectomy for treating medically intractable
temporal lobe epilepsy,” Neurosurgery, vol. 33, no. 1, pp. 50–
57, 1993.
T. Hori, F. Yamane, T. Ochiai, M. Hayashi, and T. Taira,
“Subtemporal amygdalohippocampectomy prevents verbal
memory impairment in the language-dominant hemisphere,”
Stereotactic and Functional Neurosurgery, vol. 80, no. 1–4, pp.
18–21, 2003.
S. Takaya, N. Mikuni, T. Mitsueda et al., “Improved cerebral
function in mesial temporal lobe epilepsy after subtemporal
amygdalohippocampectomy,” Brain, vol. 132, no. 1, pp. 185–
194, 2009.
H. G. Wieser and A. Häne, “Antiepileptic drug treatment before and after selective amygdalohippocampectomy,”
Epilepsy Research, vol. 55, no. 3, pp. 211–223, 2003.
Epilepsy Research and Treatment
[27] T. Hori, F. Yamane, T. Ochiai et al., “Selective subtemporal amygdalohippocampectomy for refractory temporal lobe
epilepsy: operative and neuropsychological outcomes,” Journal
of Neurosurgery, vol. 106, no. 1, pp. 134–141, 2007.
[28] G. Acar, F. Acar, J. Miller, D. C. Spencer, and K. J. Burchiel,
“Seizure outcome following transcortical selective amygdalohippocampectomy in mesial temporal lobe epilepsy,” Stereotactic and Functional Neurosurgery, vol. 86, no. 5, pp. 314–319,
2008.
[29] S. A. Renowden, Z. Matkovic, C. B. T. Adams et al., “Selective
amygdalohippocampectomy for hippocampal sclerosis: postoperative MR appearance,” American Journal of Neuroradiology, vol. 16, no. 9, pp. 1855–1861, 1995.
[30] F. Arruda, F. Cendes, F. Andermann et al., “Mesial atrophy
and outcome after amygdalohippocampectomy or temporal
lobe removal,” Annals of Neurology, vol. 40, no. 3, pp. 446–450,
1996.
[31] R. A. Mackenzie, J. Matheson, M. Ellis, and J. Klamus,
“Selective versus non-selective temporal lobe surgery for
epilepsy,” Journal of Clinical Neuroscience, vol. 4, no. 2, pp.
152–154, 1997.
[32] H. Clusmann, J. Schramm, T. Kral et al., “Prognostic factors
and outcome after different types of resection for temporal
lobe epilepsy,” Journal of Neurosurgery, vol. 97, no. 5, pp. 1131–
1141, 2002.
[33] M. Morino, T. Uda, K. Naito et al., “Comparison of neuropsychological outcomes after selective amygdalohippocampectomy versus anterior temporal lobectomy,” Epilepsy and
Behavior, vol. 9, no. 1, pp. 95–100, 2006.
[34] E. Paglioli, A. Palmini, M. Portuguez et al., “Seizure and
memory outcome following temporal lobe surgery: selective
compared with nonselective approaches for hippocampal
sclerosis,” Journal of Neurosurgery, vol. 104, no. 1, pp. 70–78,
2006.
[35] T. Tanriverdi, A. Olivier, N. Poulin, F. Andermann, and F.
Dubeau, “Long-term seizure outcome after mesial temporal lobe epilepsy surgery: corticalamygdalohippocampectomy
versus selective amygdalohippocampectomy,” Journal of Neurosurgery, vol. 108, no. 3, pp. 517–524, 2008.
[36] T. Tanriverdi, R. W. R. Dudley, A. Hasan et al., “Memory
outcome after temporal lobe epilepsy surgery: corticoamygdalohippocampectomy versus selective amygdalohippocampectomy—clinical article,” Journal of Neurosurgery, vol.
113, no. 6, pp. 1164–1175, 2010.
[37] H. G. Wieser, M. Ortega, A. Friedman, and Y. Yonekawa,
“Long-term seizure outcomes following amygdalohippocampectomy,” Journal of Neurosurgery, vol. 98, no. 4, pp. 751–763,
2003.
[38] M. T. Lutz, H. Clusmann, C. E. Elger, J. Schramm, and
C. Helmstaedter, “Neuropsychological outcome after selective amygdalohippocampectomy with transsylvian versus
transcortical approach: a randomized prospective clinical trial
of surgery for temporal lobe epilepsy,” Epilepsia, vol. 45, no. 7,
pp. 809–816, 2004.
[39] H. Clusmann, T. Kral, U. Gleissner et al., “Analysis of different
types of resection for pediatric patients with temporal lobe
epilepsy,” Neurosurgery, vol. 54, no. 4, pp. 847–860, 2004.
[40] A. Datta, D. B. Sinclair, M. Wheatley et al., “Selective
amygdalohippocampectomy: surgical outcome in children
versus adults,” Canadian Journal of Neurological Sciences, vol.
36, no. 2, pp. 187–191, 2009.
7
[41] L. Bartha, E. Trinka, M. Ortler et al., “Linguistic deficits following left selective amygdalohippocampectomy: a prospective study,” Epilepsy and Behavior, vol. 5, no. 3, pp. 348–357,
2004.
[42] U. Gleissner, C. Helmstaedter, J. Schramm, and C. E. Elger,
“Memory outcome after selective amygdalohippocampectomy
in patients with temporal lobe epilepsy: one-year follow-up,”
Epilepsia, vol. 45, no. 8, pp. 960–962, 2004.
[43] M. Morino, T. Ichinose, T. Uda, K. Kondo, S. Ohfuji, and
K. Ohata, “Memory outcome following transsylvian selective
amygdalohippocampectomy in 62 patients with hippocampal
sclerosis: clinical article,” Journal of Neurosurgery, vol. 110, no.
6, pp. 1164–1169, 2009.
[44] L. H. Goldstein and C. E. Polkey, “Short-term cognitive
changes after unilateral temporal lobectomy or unilateral
amygdalo-hippocampectomy for the relief of temporal lobe
epilepsy,” Journal of Neurology Neurosurgery and Psychiatry,
vol. 56, no. 2, pp. 135–140, 1993.
[45] C. Helmstaedter, S. Richter, S. Röske, F. Oltmanns, J.
Schramm, and T. N. Lehmann, “Differential effects of temporal pole resection with amygdalohippocampectomy versus selective amygdalohippocampectomy on material-specific
memory in patients with mesial temporal lobe epilepsy,”
Epilepsia, vol. 49, no. 1, pp. 88–97, 2008.
[46] M. J. Hamberger, W. T. Seidel, R. R. Goodman, K. Perrine, and
G. M. McKhann, “Temporal lobe stimulation reveals anatomic
distinction between auditory naming processes,” Neurology,
vol. 60, no. 9, pp. 1478–1483, 2003.
[47] M. J. Hamberger, S. McClelland, G. M. McKhann, A. C.
Williams, and R. R. Goodman, “Distribution of auditory and
visual naming sites in nonlesional temporal lobe epilepsy
patients and patients with space-occupying temporal lobe
lesions,” Epilepsia, vol. 48, no. 3, pp. 531–538, 2007.
[48] S. Dupont, A. C. Croizé, F. Semah et al., “Is amygdalohippocampectomy really selective in medial temporal lobe
epilepsy? A study using positron emission tomography with
fiuorodeoxyglucose,” Epilepsia, vol. 42, no. 6, pp. 731–740,
2001.
[49] C. Helmstaedter, T. Grunwald, K. Lehnertz, U. Gleißner, and
C. E. Elger, “Differential involvement of left temporolateral
and temporomesial structures in verbal declarative learning
and memory: evidence from temporal lobe epilepsy,” Brain
and Cognition, vol. 35, no. 1, pp. 110–131, 1997.
[50] E. Pauli, S. Pickel, H. Schulemann, M. Buchfelder, and H.
Stefan, “Neuropsychologic findings depending on the type
of the resection in temporal lobe epilepsy,” Advances in
Neurology, vol. 81, pp. 371–377, 1999.
[51] C. Helmstaedter, M. Reuber, and C. C. E. Elger, “Interaction
of cognitive aging and memory deficits related to epilepsy
surgery,” Annals of Neurology, vol. 52, no. 1, pp. 89–94, 2002.
[52] R. L. Wolf, R. J. Ivnik, K. A. Hirschorn, F. W. Sharbrough,
G. D. Cascino, and W. R. Marsh, “Neurocognitive efficiency
following left temporal lobectomy: standard versus limited
resection,” Journal of Neurosurgery, vol. 79, no. 1, pp. 76–83,
1993.
[53] M. Jones-Gotman, R. J. Zatorre, A. Olivier et al., “Learning
and retention of words and designs following excision from
medial or lateral temporal lobe structures,” Neuropsychologia,
vol. 35, no. 7, pp. 963–973, 1997.
[54] H. G. Wieser, “Selective amygdalo-hippocampectomy for
temporal lobe epilepsy,” Epilepsia, vol. 29, supplement 2, pp.
S100–S113, 1988.
8
[55] S. Colnat-Coulbois, K. Mok, D. Klein, S. Pénicaud, T.
Tanriverdi, and A. Olivier, “Tractography of the amygdala and
hippocampus: anatomical study and application to selective
amygdalohippocampectomy—laboratory investigation,” Journal of Neurosurgery, vol. 113, no. 6, pp. 1135–1143, 2010.
[56] R. A. Egan, W. T. Shults, N. So, K. Burchiel, J. X. Kellogg,
and M. Salinsky, “Visual field deficits in conventional anterior temporal lobectomy versus amygdalohippocampectomy,”
Neurology, vol. 55, no. 12, pp. 1818–1822, 2000.
[57] T. Mengesha, M. Abu-Ata, K. F. Haas et al., “Visual field defects
after selective amygdalohippocampectomy and standard temporal lobectomy,” Journal of Neuro-Ophthalmology, vol. 29, no.
3, pp. 208–213, 2009.
Epilepsy Research and Treatment