Impaired associative memory in temporal lobe epilepsy subjects after lesions of hippocampus, parahippocampal gyrus, and amygdala

Hippocampus ◽  
2004 ◽  
Vol 14 (6) ◽  
pp. 785-796 ◽  
Author(s):  
Godehard Weniger ◽  
Katrin Boucsein ◽  
Eva Irle
Keyword(s):  
Temporal Lobe Epilepsy ◽  
Associative Memory ◽  
Temporal Lobe ◽  
Parahippocampal Gyrus

Subtemporal transparahippocampal amygdalohippocampectomy for surgical treatment of mesial temporal lobe epilepsy

1996 ◽  
Vol 1 (4) ◽  
pp. E2 ◽  
Author(s):  
T. S. Park ◽  
Blaise F. D. Bourgeois ◽  
Daniel L. Silbergeld ◽  
W. Edwin Dodson
Keyword(s):  
Temporal Lobe Epilepsy ◽  
Temporal Lobe ◽  
Pediatric Patients ◽  
Mesial Temporal Lobe Epilepsy ◽  
Fusiform Gyrus ◽  
Parahippocampal Gyrus ◽  
Middle Temporal Gyrus ◽  
Language Mapping ◽  
Mesial Temporal Lobe ◽  
Sodium Amobarbital

Amygdalohippocampectomy (AH) is an accepted surgical option for treatment of medically refractory mesial temporal lobe epilepsy. Operative approaches to the amygdala and hippocampus that previously have been reported include: the sylvian fissure, the superior temporal sulcus, the middle temporal gyrus, and the fusiform gyrus. Regardless of the approach, AH permits not only extirpation of an epileptogenic focus in the amygdala and anterior hippocampus, but interruption of pathways of seizure spread via the entorhinal cortex and the parahippocampal gyrus. The authors report a modification of a surgical technique for AH via the parahippocampal gyrus, in which excision is limited to the anterior hippocampus, amygdala and parahippocampal gyrus while preserving the fusiform gyrus and the rest of the temporal lobe. Because transparahippocampal AH avoids injury to the fusiform gyrus and the lateral temporal lobe, it can be performed without intracarotid sodium amobarbital testing of language dominance and language mapping. Thus the operation would be particularly suitable for pediatric patients in whom intraoperative language mapping before resection is difficult.

scholarly journals P.035 Correlation of thalamic connectivity with the duration of epilepsy in patients with temporal lobe epilepsy

2017 ◽  
Vol 44 (S2) ◽  
pp. S22-S22
Author(s):  
B Santyr ◽  
JC Lau ◽  
SM Mirsattari ◽  
JG Burneo ◽  
S de Ribaupierre ◽  
...  
Keyword(s):  
Temporal Lobe Epilepsy ◽  
Temporal Lobe ◽  
Surgical Outcomes ◽  
Parahippocampal Gyrus ◽  
Probabilistic Tractography ◽  
Temporal Lobes ◽  
Surgical Success ◽  
False Discovery ◽  
Long Duration ◽  
Temporal Neocortex

Background: Morphometry and connectivity studies targeting the thalamus have revealed specific patterns of atrophy and deafferentiation in patients with temporal lobe epilepsy (TLE). We used probabilistic tractography to investigate thalamic connectivity with respect to duration of epilepsy and surgical outcomes in TLE. Methods: Patients (N=20) with drug-resistant TLE (10 short duration (<15 years), 10 long duration (>15 years)) were scanned with multi-parametric 3T MRI and compared with 34 healthy controls. The Harvard-Oxford atlas was modified to create 14 target regions in the temporal lobes. Probabilistic tractography (FSL) was used to delineate thalamic sub-regions most connected to each target. The volume, mean T1, T2, FA and MD of each thalamic sub-region was quantified. Surgical success was quantified using Engel outcome scores. Results: Significant decreases in thalamic connected volumes to the hippocampus in patients with longer duration of TLE were revealed. Likewise, when stratified based on surgical success, significant differences in diffusion metrics to the hippocampus, parahippocampal gyrus, and temporal neocortex were found. Significant differences did not withstand false discovery rate (FDR) correction. Conclusions: These findings suggest ongoing connectivity changes dependent on epilepsy duration and promote further investigation into the use of thalamic connectivity data as biomarkers for predicting surgical outcomes in TLE patients.

scholarly journals Evaluation of Brain Structure Based on Voxel and Surface Morphology in Adults with MRI Negative Temporal Lobe Epilepsy

2022 ◽  
Author(s):  
Fan Yang ◽  
Hanjiaerbieke Kukun ◽  
Wenxiao Jia ◽  
Shuang Ding ◽  
Wei Zhao ◽  
...  
Keyword(s):  
Temporal Lobe Epilepsy ◽  
Temporal Lobe ◽  
Gray Matter ◽  
Age Of Onset ◽  
Morphological Changes ◽  
Fusiform Gyrus ◽  
Parahippocampal Gyrus ◽  
Middle Temporal Gyrus ◽  
Control Group ◽  
Middle Temporal

Abstract Background MRI-negative TLE (TLE-N) is a manifestation lacks visible MRI findings yet with detectable electrophysiological changes. In this study, differences of gray matter in drug-controlled MRI negative temporal lobe epilepsy (cTLE-N) and drug-resistant MRI negative temporal lobe epilepsy (rTLE-N) patients were calculated and analyzed by voxel-based morphology (VBM) and surface-based morphology (SBM), to discover the brain structural changes of TLE-N patients. Materials and methods Consecutive resident patients with 30 cTLE-N and 21 rTLE-N were recruited into respective groups, and 30 healthy controls’ structural MRI (sMRI) data collected as a control group. Open-source software based on VBM and SBM was deployed as gray matter volume (GMV) and cortical thickness (CT) analytic tools. Results VBM analysis showed that GMV of bilateral thalamus and right lingual gyrus of cTLE-N group, and left hippocampus, left fusiform gyrus and left thalamus of rTLE-N group were smaller compared to HC group(FDR corrected, P<0.05), while right cerebellum, inferior temporal gyrus, hippocampus, parahippocampal gyrus, amygdala, fusiform gyrus, orbital middle frontal gyrus, and left posterior central gyrus in cTLE-N group, and bilateral cerebellum and middle temporal gyrus, right fusiform gyrus, amygdala, hippocampus, and left middle occipital gyrus of rTLE-N group were greater than HC group(FDR corrected, P<0.05). SBM analysis showed that CT of the left medial orbitofrontal cortex and lateral occipital cortex in cTLE-N group, and thickness of the left medial orbitofrontal, temporal pole, middle temporal gyrus and right anterior superior cingulate cortex in rTLE-N group were thinner, compared to HC group. Correlation analysis showed that GMV and CT of different structures were correlated with age of onset, disease duration, and MoCA score. Conclusion This study utilized two different sMRI analytic tools and discovered several brain morphological changes in TLE-N. These morphological changes were also correlated with clinical variables. Further study may indicate the potential of these findings on the recognition of the TLE-N epilepsy network.

scholarly journals Tractography of the parahippocampal gyrus and material specific memory impairment in unilateral temporal lobe epilepsy

NeuroImage ◽  
2008 ◽  
Vol 40 (4) ◽  
pp. 1755-1764 ◽  
Author(s):  
M. Yogarajah ◽  
H.W.R. Powell ◽  
G.J.M Parker ◽  
D.C. Alexander ◽  
P.J. Thompson ◽  
...  
Keyword(s):  
Temporal Lobe Epilepsy ◽  
Temporal Lobe ◽  
Memory Impairment ◽  
Parahippocampal Gyrus ◽  
Specific Memory

scholarly journals P.189 Unruptured Posterior Cerebral Artery aneurysm causing temporal lobe epilepsy

2021 ◽  
Vol 48 (s3) ◽  
pp. S74-S75
Author(s):  
M Fatehi Hassanabad ◽  
G Redekop ◽  
LS Yefet
Keyword(s):  
Temporal Lobe Epilepsy ◽  
Temporal Lobe ◽  
Cerebral Artery ◽  
Rare Case ◽  
Posterior Cerebral Artery ◽  
Cerebral Aneurysms ◽  
Artery Aneurysm ◽  
Parahippocampal Gyrus ◽  
Temporal Lobe Seizures ◽  
Cerebral Artery Aneurysm

Background: Cerebral aneurysms are an unusal cause of epilepsy. To date, several groups have reported temporal lobe seizures caused by aneurysms projecting into the parahippocampal gyrus. Given the low incidence of posterior cerebral artery aneurysms, they are a very rare cause of temporal lobe seizures. Methods: Here, we report a rare case of temporal lobe epilepsy caused by an unruptured aneurysm. We also present a review of the literature yielding two similar cases. Results: A previosuly well 56 year old male presented to a neurologist with symptoms consistent with temporal lobe epilepsy. He was started on carbamzepine and underwent imaging and neuropsychological assessments. An MRI suggested the existance of a 7mm posterior cerebral artery aneurysm arising from the P2 segment of the posterior cerebral artery and projecting into the parahippocampal gyrus. This was also confirmed with CT angiography and the patient elected to have the aneurysm clipped. Conclusions: Temporal lobe epilepsy is an uncommon presentation for unruptured cerebral aneurysms. We report a rare case wherein a laterally pointing PCA aneurysm was buried in the posterior parahippocampal gyrus. This aneurysm had caused perifocal gliosis leading to stereotyped seizures. Post-operatively, the patient has been seizure free.

Subtemporal transparahippocampal amygdalohippocampectomy for surgical treatment of mesial temporal lobe epilepsy

1996 ◽  
Vol 85 (6) ◽  
pp. 1172-1176 ◽  
Author(s):  
T. S. Park ◽  
Blaise F. D. Bourgeois ◽  
Daniel L. Silbergeld ◽  
W. Edwin Dodson
Keyword(s):  
Temporal Lobe Epilepsy ◽  
Temporal Lobe ◽  
Mesial Temporal Lobe Epilepsy ◽  
Fusiform Gyrus ◽  
Parahippocampal Gyrus ◽  
Middle Temporal Gyrus ◽  
Language Mapping ◽  
Content Type ◽  
Mesial Temporal Lobe ◽  
Sodium Amobarbital

✓ Amygdalohippocampectomy (AH) is an accepted surgical option for treatment of medically refractory mesial temporal lobe epilepsy. Operative approaches to the amygdala and hippocampus that previously have been reported include: the sylvian fissure, the superior temporal sulcus, the middle temporal gyrus, and the fusiform gyrus. Regardless of the approach, AH permits not only extirpation of an epileptogenic focus in the amygdala and anterior hippocampus, but interruption of pathways of seizure spread via the entorhinal cortex and the parahippocampal gyrus. The authors report a modification of a surgical technique for AH via the parahippocampal gyrus, in which excision is limited to the anterior hippocampus, amygdala and parahippocampal gyrus while preserving the fusiform gyrus and the rest of the temporal lobe. Because transparahippocampal AH avoids injury to the fusiform gyrus and the lateral temporal lobe, it can be performed without intracarotid sodium amobarbital testing of language dominance and language mapping. Thus the operation would be particularly suitable for pediatric patients in whom intraoperative language mapping before resection is difficult.

scholarly journals Transcranial magnetic resonance–guided focused ultrasound for temporal lobe epilepsy: a laboratory feasibility study

2016 ◽  
Vol 125 (6) ◽  
pp. 1557-1564 ◽  
Author(s):  
Stephen Monteith ◽  
John Snell ◽  
Mathew Eames ◽  
Neal F. Kassell ◽  
Edward Kelly ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Temporal Lobe Epilepsy ◽  
Skull Base ◽  
Temporal Lobe ◽  
Focused Ultrasound ◽  
Temporal Lobectomy ◽  
Parahippocampal Gyrus ◽  
Maximum Temperature ◽  
Target Tissue ◽  
Mesial Temporal Lobe

OBJECTIVE In appropriate candidates, the treatment of medication-refractory mesial temporal lobe epilepsy (MTLE) is primarily surgical. Traditional anterior temporal lobectomy yields seizure-free rates of 60%–70% and possibly higher. The field of magnetic resonance–guided focused ultrasound (MRgFUS) is an evolving field in neurosurgery. There is potential to treat MTLE with MRgFUS; however, it has appeared that the temporal lobe structures were beyond the existing treatment envelope of currently available clinical systems. The purpose of this study was to determine whether lesional temperatures can be achieved in the target tissue and to assess potential safety concerns. METHODS Cadaveric skulls with tissue-mimicking gels were used as phantom targets. An ablative volume was then mapped out for a “virtual temporal lobectomy.” These data were then used to create a target volume on the InSightec ExAblate Neuro system. The target was the amygdala, uncus, anterior 20 mm of hippocampus, and adjacent parahippocampal gyrus. This volume was approximately 5cm3. Thermocouples were placed on critical skull base structures to monitor skull base heating. RESULTS Adequate focusing of the ultrasound energy was possible in the temporal lobe structures. Using clinically relevant ultrasound parameters (power 900 W, duration 10 sec, frequency 650 kHz), ablative temperatures were not achieved (maximum temperature 46.1°C). Increasing sonication duration to 30 sec demonstrated lesional temperatures in the mesial temporal lobe structures of interest (up to 60.5°C). Heating of the skull base of up to 24.7°C occurred with 30-sec sonications. CONCLUSIONS MRgFUS thermal ablation of the mesial temporal lobe structures relevant in temporal lobe epilepsy is feasible in a laboratory model. Longer sonications were required to achieve temperatures that would create permanent lesions in brain tissue. Heating of the skull base occurred with longer sonications. Blocking algorithms would be required to restrict ultrasound beams causing skull base heating. In the future, MRgFUS may present a minimally invasive, non-ionizing treatment of MTLE.

Modified approach for the selective treatment of temporal lobe epilepsy: transsylvian—transcisternal mesial en bloc resection

1998 ◽  
Vol 88 (5) ◽  
pp. 855-862 ◽  
Author(s):  
Peter Vajkoczy ◽  
Karsten Krakow ◽  
Stefan Stodieck ◽  
Bernd Pohlmann-Eden ◽  
Peter Schmiedek
Keyword(s):  
Temporal Lobe Epilepsy ◽  
Temporal Lobe ◽  
En Bloc Resection ◽  
Bloc Resection ◽  
Parahippocampal Gyrus ◽  
Oculomotor Nerve Palsy ◽  
En Bloc ◽  
Content Type ◽  
Mesial Temporal Lobe ◽  
Fine Print

Object. The authors propose a novel surgical approach for amygdalohippocampectomy (AH) in patients with temporal lobe epilepsy. Via a transsylvian—transcisternal route, the parahippocampal gyrus is directly exposed from its medial aspect, thus allowing a standardized en bloc resection of the temporomesial epileptogenic structures—the amygdala, anterior hippocampus, parahippocampal gyrus, and subiculum. Additional anatomical studies have been performed for standardization of this approach. Methods. From 1990 to 1996, 32 patients presenting with medically intractable mesial temporal lobe epilepsy underwent AH via the transsylvian—transcisternal approach. Preoperative computerized tomography and magnetic resonance imaging revealed temporomesial lesions in 16 patients. Histopathological examination revealed cavernous malformations in seven patients, low-grade astrocytomas in four, hamartomas in three, and gangliogliomas in two patients. Specimens obtained in patients with no lesions were diagnosed as hippocampal sclerosis in all cases. No patient experienced permanent morbidity. Nine percent of the patients developed a temporary partial oculomotor nerve palsy. Only one patient developed a postoperative visual field deficit with a contralateral quadrantanopsia. With respect to seizure outcome, all patients benefited from surgery. At follow-up evaluation (mean 26.4 months), 80% of the patients were free from seizures (Engel Class I). Eight patients in this group were no longer receiving medication. Seventeen percent had experienced only one to several seizures since surgery (Engel Class II) and 3% reported a worthwhile improvement (Engel Class III). Conclusions. In contrast to previously described standard techniques for AH, the transsylvian—transcisternal approach presented in this study offers improved anatomical orientation and intraoperative control over the mesial temporal lobe and preserves the lateral as well as the laterobasal temporal lobe.

Use of an anteromedial subdural strip electrode in the evaluation of medial temporal lobe epilepsy

2003 ◽  
Vol 99 (5) ◽  
pp. 921-923 ◽  
Author(s):  
Aaron A. Cohen-Gadol ◽  
Dennis D. Spencer
Keyword(s):  
Temporal Lobe Epilepsy ◽  
Temporal Lobe ◽  
Medial Temporal Lobe ◽  
Parahippocampal Gyrus ◽  
Content Type ◽  
Strip Electrode ◽  
Temporal Pole ◽  
Method Of Placement ◽  
Adequate Coverage ◽  
Medial Temporal Lobe Epilepsy

✓ The temporal lobe is the most common site of partial epilepsy that is amenable to surgical therapy, and therefore ictal localization in this region is important. The authors describe the application of an anteromedial subdural strip electrode for the evaluation of epilepsy originating from the medial temporal lobe. This strip is advanced around the temporal pole and underneath the lesser wing of the sphenoid bone as it follows the medial temporal lobe contour. The advantages of this method of placement are the consistent path and reliable final position of the strip along the medial basal temporal lobe surface. This method allows adequate coverage of the parahippocampal gyrus along its long axis extending posterior to the level of the collicular plate. This technique has been used with no complications during intracranial monitoring of more than 100 patients with presumed temporal lobe epilepsy.

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