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Keith G. Davies - One of the best experts on this subject based on the ideXlab platform.
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intracarotid amobarbital procedure and prediction of postoperative memory in patients with left temporal lobe epilepsy and Hippocampal Sclerosis
Epilepsia, 2000Co-Authors: Brian Bell, Keith G. Davies, Alan M Haltiner, Gina WaltersAbstract:Summary: Purpose: Although temporal lobe epilepsy (TLE) patients with dominant hemisphere Hippocampal Sclerosis generally have good cognitive outcome after anterior temporal lobectomy (ATL), a minority of patients experience at least mild post-ATL decline on one or more standardized measures of episodic and semantic memory. The goal of this investigation was to determine whether memory outcome in this group could be predicted from preoperative intracarotid amobarbital procedure (IAP) recognition memory scores. Methods: Data from 22 left TLE patients were studied retrospectively. All were left hemisphere language dominant and had IAP scores for each hemisphere, a significant degree of pathology-confirmed left Hippocampal Sclerosis (HS+), and no positive MRI findings other than atrophy. Cognitive outcome status was represented by the number of pre- to post-ATL declines across three tests, as defined by 90th percentile Reliable Change Index (RCI) criteria. Results: Only 14% of the sample exhibited decline on more than one memory test. Low right IAP (left hemisphere injection) scores and relatively high preoperative cognitive ability and age at surgery predicted a greater risk of post-ATL memory decline. Conclusions: A minority of left TLE HS+ patients experience at least a mild degree of RCI-defined decline in episodic or semantic memory after ATL. The right hemisphere IAP memory score, which reflects the functional reserve of the contralateral hemisphere, can help predict the risk of postoperative memory decline for TLE patients in whom HS+ is likely based on the presence of Hippocampal atrophy on MRI or early age of seizure onset.
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prediction of presence of Hippocampal Sclerosis from intracarotid amobarbital procedure memory asymmetry scores and epilepsy onset age
Epilepsy Research, 1999Co-Authors: Brian D. Bell, Keith G. Davies, Curtis F Dohan, John B Schweitzer, Bruce P. HermannAbstract:Abstract Identification of the pathological status of the hippocampus prior to surgery is important since the absence of Hippocampal Sclerosis (HS) carries risks to memory function following anterior temporal lobectomy (ATL). We studied 62 patients undergoing ATL (31 L, 31 R) for intractable epilepsy of temporal lobe origin in whom no pathology was identified apart from HS. An intracarotid amobarbital procedure (IAP) was performed as part of the preoperative evaluation. All patients were left hemisphere dominant for language. IAP memory testing was according to the protocol of Loring 15 . We examined IAP memory asymmetry scores at four levels of difference (
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Anterior Temporal Lobectomy, Hippocampal Sclerosis, and Memory: Recent Neuropsychological Findings
Neuropsychology Review, 1998Co-Authors: Brian D. Bell, Keith G. DaviesAbstract:Anterior temporal lobectomy (ATL) is an effective and increasingly utilized treatment for nonlesional, intractable mesial temporal lobe epilepsy. However, this surgery results in domain-specific neuropsychological morbidity for a subset of patients. Within the past decade, multidisciplinary studies have revealed that left ATL patients without significant Sclerosis in the resected hippocampus are most at risk for a substantial postacute decline in the ability to encode new verbal information. These patients are also at risk for a significant decrement in confrontation naming and other retrieval-based language abilities. The memory deficit is not attributable to this disruption of language. A relationship between Hippocampal Sclerosis (HS) status and memory performance has not been identified consistently in right ATL patients, but investigation of new visuospatial measures continues. The influence of variables other than HS on neuropsychological outcome is also discussed.
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relationship of Hippocampal Sclerosis to duration and age of onset of epilepsy and childhood febrile seizures in temporal lobectomy patients
Epilepsy Research, 1996Co-Authors: Bruce P. Hermann, Keith G. Davies, Curtis F Dohan, Kevin T Foley, Andrew J Bush, Allen R. WylerAbstract:Abstract Controversy exists as to whether Hippocampal Sclerosis (HS) is a preexisting cause or a consequence of seizures. We investigated 122 consecutive patients who underwent anterior temporal lobectomy for intractable epilepsy between 1989 and 1992. MRI scans were normal apart from evidence of HS in 5 cases. The degree of HS was graded from 0 to 4. There was a significant inverse correlation between age of seizure onset and grade of HS ( P P P = 0.003), earlier age of onset of epilepsy ( P P P
Dennis W Dickson - One of the best experts on this subject based on the ideXlab platform.
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common variant in grn is a genetic risk factor for Hippocampal Sclerosis in the elderly
Neurodegenerative Diseases, 2010Co-Authors: Dennis W Dickson, Matt Baker, Rosa RademakersAbstract:Background: Hippocampal Sclerosis (HpScl) is common in elderly subjects with dementia, either alone or accompanied by other pathologic processes. It is also found in >70% of frontot
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Hippocampal Sclerosis in tau negative frontotemporal lobar degeneration
Neurobiology of Aging, 2007Co-Authors: Keith A Josephs, Dennis W DicksonAbstract:Tau-negative frontotemporal lobar degeneration (FTLD) can be divided into those with motor neuron disease (FTLD-MND), and those without MND, but with ubiquitin-immunoreactive neuronal inclusions (FTLD-U). Some authors group FTLD-U and FTLD-MND together as tau-negative FTLD, but others separate them on the basis of clinical, pathologic and imaging differences. In 103 cases of pathologically confirmed, tau-negative FTLD (FTLD-MND and FTLD-U), we assessed the frequency of Hippocampal Sclerosis defined as neuronal loss in the subicular or CA1 regions of the hippocampus. The subjects in the FTLD-U group were older at death and had longer disease duration. After adjusting for age at death and disease duration, we found a significant difference in the frequency of Hippocampal Sclerosis in the FTLD-U group (79%) compared to FTLD-MND group (26%) (p = 0.02). The difference in frequency of HpScl in FTLD-U compared to FTLD-MND is further evidence that they are separate clinicopathologic entities.
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tdp 43 immunoreactivity in Hippocampal Sclerosis and alzheimer s disease
Annals of Neurology, 2007Co-Authors: Catalina Amadorortiz, Mike Hutton, Zeshan Ahmed, Wen Lang Lin, David Personett, Peter Davies, Ranjan Duara, Neill R Graffradford, Dennis W DicksonAbstract:Objective This study aimed to determine the frequency of frontotemporal lobar degeneration with ubiquitinated inclusions (FTLD-U) in the setting of Hippocampal Sclerosis (HpScl) and Alzheimer's disease (AD) using immunohistochemistry for TAR DNA binding protein 43 (TDP-43), a putative marker for FTLD-U. Methods Initially, 21 cases of HpScl associated with a variety of other pathological processes and 74 cases of AD were screened for FTLD-U with TDP-43 immunohistochemistry. A confirmation study was performed on 93 additional AD cases. Specificity of TDP-43 antibodies was assessed using double-immunolabeling confocal microscopy, immunoelectron microscopy, and biochemistry. Results TDP-43 immunoreactivity was detected in 71% of HpScl and 23% of AD cases. Double immunostaining of AD cases for TDP-43 and phospho-tau showed that the TDP-43–immunoreactive inclusions were usually distinct from neurofibrillary tangles. At the ultrastructural level, TDP-43 immunoreactivity in AD was associated with granular and filamentous cytosolic material and only occasionally associated with tau filaments. Western blots of AD cases showed a band that migrated at a higher molecular weight than normal TDP-43 that was not present in AD cases without TDP-43 immunoreactivity. Interpretation These results suggest that as many as 20% of AD cases and more than 70% of HpScl cases have pathology similar to that found in FTLD-U. Whether this represents concomitant FTLD-U or is analogous to colocalization of α-synuclein and tau in AD, reflecting a propensity for codeposition of abnormal protein conformers, remains to be determined. Ann Neurol 2007;61:435–445
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Hippocampal Sclerosis dementia differs from Hippocampal Sclerosis in frontal lobe degeneration
Acta Neuropathologica, 2007Co-Authors: Catalina Amador-ortiz, Zeshan Ahmed, Cynthia Zehr, Dennis W DicksonAbstract:Hippocampal Sclerosis (HS) is characterized by selective neuronal loss and gliosis in CA1 and the subiculum and has been associated with several disorders, including Alzheimer’s disease, frontotemporal lobar degeneration with ubiquitin immunoreactive inclusions (FTLD-U), vascular dementia and some tauopathies. In some cases, HS is not associated with other degenerative pathologies. Such cases are sometimes referred to as HS dementia (HSD). Differences between HSD and HS in the setting of FTLD-U have not been systematically investigated. To this end, eight cases of HSD and ten cases of HS associated with FTLD-U were studied with Nissl and periodic acid-Schiff stains to assess neuronal loss and corpora amylacea, respectively. Sections were immunostained with antibodies to glial fibrillary acidic protein, HLA-DR and synaptophysin and immunoreactivity was measured with image analysis in CA1 and the subiculum of each case. Additionally, sections were immunostained with antibodies to 4-R tau to determine the presence of argyrophilic grains. HSD was different from HS associated with FTLD-U. Specifically, it was more common in the elderly, and it was associated with more marked neuronal and synaptic loss and with greater reactive gliosis. Corpora amylacea tended to be more frequent in HSD than in FTLD-U, but there was no difference in frequency of argyrophilic grains.
John S. Duncan - One of the best experts on this subject based on the ideXlab platform.
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Temporal lobe Sclerosis associated with Hippocampal Sclerosis in temporal lobe epilepsy: neuropathological features.
Journal of Neuropathology and Experimental Neurology, 2009Co-Authors: Maria Thom, John S. Duncan, Sofia H Eriksson, Lillian Martinian, Luis O. Caboclo, Andrew W. Mcevoy, Sanjay M. SisodiyaAbstract:Widespread changes involving neocortical and mesial temporal lobe structures can be present in patients with temporal lobe epilepsy and Hippocampal Sclerosis. The incidence, pathology, and clinical significance of neocortical temporal lobe Sclerosis (TLS) are not well characterized. We identified TLS in 30 of 272 surgically treated cases of Hippocampal Sclerosis. Temporal lobe Sclerosis was defined by variable reduction of neurons from cortical layers II/III and laminar gliosis; it was typically accompanied by additional architectural abnormalities of layer II, that is, abnormal neuronal orientation and aggregation. Quantitative analysis including tessellation methods for the distribution of layer II neurons supported these observations. In 40% of cases, there was a gradient of TLS with more severe involvement toward the temporal pole, possibly signifying involvement of Hippocampal projection pathways. There was a history of a febrile seizure as an initial precipitating injury in 73% of patients with TLS compared with 36% without TLS; no other clinical differences between TLS and non-TLS cases were identified. Temporal lobe Sclerosis was not evident preoperatively by neuroimaging. No obvious effect of TLS on seizure outcome was noted after temporal lobe resection; 73% became seizure-free at 2-year follow-up. In conclusion, approximately 11% of surgically treated Hippocampal Sclerosis is accompanied by TLS. Temporal lobe Sclerosis is likely an acquired process with accompanying reorganizational dysplasia and an extension of mesial temporal Sclerosis rather than a separate pathological entity.
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regional changes in Hippocampal t2 relaxation and volume a quantitative magnetic resonance imaging study of Hippocampal Sclerosis
Journal of Neurology Neurosurgery and Psychiatry, 1998Co-Authors: Friedrich G Woermann, G J Barker, K Birnie, Heinz J Meencke, John S. DuncanAbstract:Objective—The principal MRI features of Hippocampal Sclerosis are volume loss and increased T2 weighted signal intensity. Minor and localised abnormalities may be overlooked without careful quantitation. Hippocampal T2 relaxation time (HT2) can be quantified, but previously has only been measured on a few thick coronal slices with interslice gaps. In this study HT2 was measured along the entire length of the hippocampus on contiguous slices and used, with quantitative measures of Hippocampal volume (HV) and distribution of atrophy, to better define the range of Hippocampal Sclerosis. Methods—Thirty patients with temporal lobe epilepsy, 10 patients with extratemporal localisation related epilepsy and extratemporal lesions, and 20 control subjects were studied using MRI T2 relaxometry and volumetry. Results—In controls and patients, HT2 was higher in the anterior than the posterior hippocampus. Using HV, morphometric, and HT2 data, patients with temporal lobe epilepsy were classified as unilateral diVuse Hippocampal Sclerosis (n=16), unilateral focal (n=6), bilaterally aVected (n=6), and normal (n=2). In patients with unilateral Hippocampal Sclerosis, the anterior hippocampus was always aVected. In three patients with normal HV, HT2 measurements disclosed unilateral focal abnormalities that corresponded to the EEG lateralisation of epileptic activity. Patients with bilateral Hippocampal involvement had an earlier onset of epilepsy than patients with unilateral Hippocampal Sclerosis. Conclusions—Measurement of regional abnormalities of HT2 along the length of the hippocampus provides further refinement to the MRI assessment of the hippocampi in patients with temporal lobe epilepsy and is complementary to volumetric and morphological data. (J Neurol Neurosurg Psychiatry 1998;65:656‐664)
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the spectrum of Hippocampal Sclerosis a quantitative magnetic resonance imaging study
Annals of Neurology, 1997Co-Authors: W Van Paesschen, Graeme D Jackson, Alan Connelly, Martin D King, John S. DuncanAbstract:One hundred patients with intractable temporal lobe epilepsy and 22 control subjects were scanned on a 1.5-T Siemens SP63 Magnetom scanner. A combination of Hippocampal T2 mapping, Hippocampal volume measurement corrected for intracranial volume, and inspection of Hippocampal morphology on a Hippocampal volume distribution graph compared with a control graph revealed previously undetected forms of bilateral Hippocampal Sclerosis and four false-positive diagnoses of Hippocampal Sclerosis made on visual inspection of the scans. A physiological asymmetry in the position of the hippocampi in 41% of control subjects and focal Hippocampal atrophies in patients made measurement of the whole length of the hippocampus mandatory. The extent of Hippocampal damage in patients with Hippocampal Sclerosis correlated with the number of secondary generalized seizures during a patient's lifetime. In contrast to patients with unilateral Hippocampal Sclerosis, patients with severe bilateral Hippocampal Sclerosis had no history of febrile convulsions. Twenty-six patients with intractable temporal lobe epilepsy had normal Hippocampal magnetic resonance imaging measures and as a group were significantly older at the onset of habitual epilepsy than were patients with Hippocampal Sclerosis. In conclusion, a combination of quantitative magnetic resonance imaging techniques revealed a spectrum of Hippocampal Sclerosis and optimally defined boundaries of Hippocampal normality. The spectrum of Hippocampal Sclerosis is related to the etiology, the number of secondary generalized seizures, and the age at onset of habitual epilepsy.
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optimizing the diagnosis of Hippocampal Sclerosis using mr imaging
American Journal of Neuroradiology, 1993Co-Authors: Graeme D Jackson, Samuel F Berkovic, John S. Duncan, Alan ConnellyAbstract:PURPOSE To establish the optimal imaging parameters and MR features of Hippocampal Sclerosis. METHODS Twenty-five outpatients with intractable temporal lobe epilepsy and 10 control subjects were studied at 1.5T. Four features of Hippocampal abnormality were specifically evaluated; increased Hippocampal signal on T2-weighted images, decreased signal on T1-weighted images, Hippocampal atrophy, and disruption of the internal Hippocampal structure. RESULTS Hippocampal Sclerosis was diagnosed alone in 64% of patients and with ipsilateral pathology in a further 8%. In these 18 cases, increased Hippocampal signal on T2-weighted images was seen in 77%, Hippocampal atrophy in 83%, decreases signal on T1-weighted images in 83%, and disruption of the internal Hippocampal structure in 89%. No abnormality was reported in any of the 10 control cases. CONCLUSIONS Four MR features diagnostic of Hippocampal Sclerosis are reported. Inversion recovery images are very useful for identifying decreased signal in the hippocampus and loss of internal structure within the hippocampus. Based on an appreciation of these four features in optimized images, Hippocampal Sclerosis can be diagnosed with a high degree of accuracy and sensitivity.
Fernando Cendes - One of the best experts on this subject based on the ideXlab platform.
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Long-term postoperative atrophy of contralateral hippocampus and cognitive function in unilateral refractory MTLE with unilateral Hippocampal Sclerosis
2020Co-Authors: Daniela Alves Fernandes, Evandro De ,oliveira, Clarissa Lin Yasuda, Tátila Martins Lopes, Enrico Ghizoni, Andréa Alessio, Helder Tedeschi, Fernando CendesAbstract:Objective: This study aimed to evaluate long-term atrophy in contralateral Hippocampal volume after surgery for unilateral MTLE, as well as the cognitive outcome for patients submitted to either selective transsylvian amygdalohippocampectomy (SelAH) or anterior temporal lobe resection (ATL). Methods: We performed a longitudinal study of 47 patients with MRI signs of unilateral Hippocampal Sclerosis (23 patients with right-sided Hippocampal Sclerosis) who underwent surgical treatment for MTLE. They underwent preoperative/postoperative high-resolution MRI as well as neuropsychological assessment for memory and estimated IQ. To investigate possible changes in the contralateral hippocampus of patients, we included 28 controls who underwent two MRIs at long-term intervals. Results: The volumetry using preoperative MRI showed significant Hippocampal atrophy ipsilateral to the side of surgery when compared with controls (p b 0.0001) but no differences in contralateral Hippocampal volumes. The mean postoperative follow-up was 8.7 years (±2.5 SD; median = 8.0). Our patients were classified as Engel I (80%), Engel II (18.2%), and Engel III (1.8%). We observed a small but significant reduction in the contralateral hippocampus of patients but no volume changes in controls. Most of the patients presented small declines in both estimated IQ and memory, which were more pronounced in patients with left TLE and in those with persistent seizures. Different surgical approaches did not impose differences in seizure control or in cognitive outcome. Conclusions: We observed small declines in cognitive scores with most of these patients, which were worse in patients with left-sided resection and in those who continued to suffer from postoperative seizures. We also demonstrated that manual volumetry can reveal a reduction in volume in the contralateral hippocampus, although this change was mild and could not be detected by visual analysis. These new findings suggest that dynamic processes continue to act after the removal of the hippocampus, and further studies with larger groups may help in understanding the underlying mechanisms
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Epilepsies associated with Hippocampal Sclerosis
Acta Neuropathologica, 2014Co-Authors: Fernando Cendes, Americo C. Sakamoto, Roberto Spreafico, William Bingaman, Albert J. BeckerAbstract:Hippocampal Sclerosis (HS) is considered the most frequent neuropathological finding in patients with mesial temporal lobe epilepsy (MTLE). Hippocampal specimens of pharmacoresistant MTLE patients that underwent epilepsy surgery for seizure control reveal the characteristic pattern of segmental neuronal cell loss and concomitant astrogliosis. However, classification issues of Hippocampal lesion patterns have been a matter of intense debate. International consensus classification has only recently provided significant progress for comparisons of neurosurgical and clinic-pathological series between different centers. The respective four-tiered classification system of the International League Against Epilepsy subdivides HS into three types and includes a term of “gliosis only, no-HS”. Future studies will be necessary to investigate whether each of these subtypes of HS may be related to different etiological factors or with postoperative memory and seizure outcome. Molecular studies have provided potential deeper insights into the pathogenesis of HS and MTLE on the basis of epilepsy-surgical Hippocampal specimens and corresponding animal models. These include channelopathies, activation of NMDA receptors, and other conditions related to Ca^2+ influx into neurons, the imbalance of Ca^2+—binding proteins, acquired channelopathies that increase neuronal excitability, paraneoplastic and non-paraneoplastic inflammatory events, and epigenetic regulation promoting or facilitating Hippocampal epileptogenesis. Genetic predisposition for HS is clearly suggested by the high incidence of family history in patients with HS, and by familial MTLE with HS. So far, it is clear that HS is multifactorial and there is no individual pathogenic factor either necessary or sufficient to generate this intriguing histopathological condition. The obvious variety of pathogenetic combinations underlying HS may explain the multitude of clinical presentations, different responses to clinical and surgical treatment. We believe that the stratification of neuropathological patterns can help to characterize specific clinic-pathological entities and predict the postsurgical seizure control in an improved fashion.
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3t mri quantification of Hippocampal volume and signal in mesial temporal lobe epilepsy improves detection of Hippocampal Sclerosis
American Journal of Neuroradiology, 2014Co-Authors: Ana Carolina Coan, Bruno Y Kubota, Felipe P G Bergo, Brunno Machado De Campos, Fernando CendesAbstract:BACKGROUND AND PURPOSE: In mesial temporal lobe epilepsy, MR imaging quantification of Hippocampal volume and T2 signal can improve the sensitivity for detecting Hippocampal Sclerosis. However, the current contributions of these analyses for the diagnosis of Hippocampal Sclerosis in 3T MRI are not clear. Our aim was to compare visual analysis, volumetry, and signal quantification of the hippocampus for detecting Hippocampal Sclerosis in 3T MRI. MATERIALS AND METHODS: Two hundred three patients with mesial temporal lobe epilepsy defined by clinical and electroencephalogram criteria had 3T MRI visually analyzed by imaging epilepsy experts. As a second step, we performed automatic quantification of Hippocampal volumes with FreeSurfer and T2 relaxometry with an in-house software. MRI of 79 healthy controls was used for comparison. RESULTS: Visual analysis classified 125 patients (62%) as having signs of Hippocampal Sclerosis and 78 (38%) as having normal MRI findings. Automatic volumetry detected atrophy in 119 (95%) patients with visually detected Hippocampal Sclerosis and in 10 (13%) with visually normal MR imaging findings. Relaxometry analysis detected hyperintense T2 signal in 103 (82%) patients with visually detected Hippocampal Sclerosis and in 15 (19%) with visually normal MR imaging findings. Considered together, volumetry plus relaxometry detected signs of Hippocampal Sclerosis in all except 1 (99%) patient with visually detected Hippocampal Sclerosis and in 22 (28%) with visually normal MR imaging findings. CONCLUSIONS: In 3T MRI visually inspected by experts, quantification of Hippocampal volume and signal can increase the detection of Hippocampal Sclerosis in 28% of patients with mesial temporal lobe epilepsy.
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unilateral Hippocampal Sclerosis with contralateral temporal scalp ictal onset
Epilepsia, 2004Co-Authors: Scott Mintzer, Fernando Cendes, Frederick Andermann, Andre Olivier, Jason Soss, Jerome Engel, Francois Dubeau, Itzhak FriedAbstract:Summary: Purpose: To investigate the clinical characteristics and surgical outcomes in patients with unilateral Hippocampal Sclerosis whose scalp ictal EEG recordings localize to the opposite temporal lobe. Methods: We retrospectively reviewed the data of all adult patients who had undergone depth electrode implantation for suspected temporal lobe epilepsy (TLE) at UCLA (1993‐2000) or the Montreal Neurological Institute (1991‐1998) to identify patients who had (a) unilateral Hippocampal atrophy, and (b) surface ictal recordings in which the majority of seizures appeared to initiate in the opposite temporal lobe, with few or none that were concordant with the Hippocampal atrophy. Results: Of 109 patients with suspected TLE who underwent depth electrode study at the two centers, five patients met the aforementioned criteria. Four of these five had very severe Hippocampal atrophy, whereas the fifth had mild atrophy but extensive signal change on magnetic resonance imaging (MRI). Depth electrode recordings in four of the five patients yielded clear ictal onset in the mesial temporal lobe ipsilateral to the imaging abnormality (contralateral to apparent scalp ictal onset). One patient had an unusual bitemporal onset pattern, which was nonetheless suggestive of onset in the sclerotic hippocampus. No patient had intracranial ictal onset contralateral to the imaging abnormality. All patients underwent resection of the structurally abnormal temporal lobe. After follow-up of ≥2 years, four (80%) of five patients were seizure free, while the fifth showed lesser improvement (class III). Conclusions: Some patients with severe Hippocampal Sclerosis (sometimes called a “burned-out hippocampus”) have atypical spread of ictal discharges, resulting in apparent gross discordance between imaging and scalp ictal recordings. These patients nonetheless have excellent surgical outcomes on the whole. Whether such patients may forego intracranial recordings requires further study. Key Words: Temporal lobe epilepsy— Hippocampal Sclerosis—Ictal recordings—Depth electrodes— Anterior temporal lobectomy.
Bruce P. Hermann - One of the best experts on this subject based on the ideXlab platform.
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prediction of presence of Hippocampal Sclerosis from intracarotid amobarbital procedure memory asymmetry scores and epilepsy onset age
Epilepsy Research, 1999Co-Authors: Brian D. Bell, Keith G. Davies, Curtis F Dohan, John B Schweitzer, Bruce P. HermannAbstract:Abstract Identification of the pathological status of the hippocampus prior to surgery is important since the absence of Hippocampal Sclerosis (HS) carries risks to memory function following anterior temporal lobectomy (ATL). We studied 62 patients undergoing ATL (31 L, 31 R) for intractable epilepsy of temporal lobe origin in whom no pathology was identified apart from HS. An intracarotid amobarbital procedure (IAP) was performed as part of the preoperative evaluation. All patients were left hemisphere dominant for language. IAP memory testing was according to the protocol of Loring 15 . We examined IAP memory asymmetry scores at four levels of difference (
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relationship of Hippocampal Sclerosis to duration and age of onset of epilepsy and childhood febrile seizures in temporal lobectomy patients
Epilepsy Research, 1996Co-Authors: Bruce P. Hermann, Keith G. Davies, Curtis F Dohan, Kevin T Foley, Andrew J Bush, Allen R. WylerAbstract:Abstract Controversy exists as to whether Hippocampal Sclerosis (HS) is a preexisting cause or a consequence of seizures. We investigated 122 consecutive patients who underwent anterior temporal lobectomy for intractable epilepsy between 1989 and 1992. MRI scans were normal apart from evidence of HS in 5 cases. The degree of HS was graded from 0 to 4. There was a significant inverse correlation between age of seizure onset and grade of HS ( P P P = 0.003), earlier age of onset of epilepsy ( P P P
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reports by patients and their families of memory change after left anterior temporal lobectomy relationship to degree of Hippocampal Sclerosis
Neurosurgery, 1995Co-Authors: Bruce P. Hermann, Allen R. Wyler, Michael Seidenberg, F Dohan, Alan M Haltiner, Julia Bobholz, Alicia PerrineAbstract:Memory decline represents the primary neuropsychological morbidity of anterior temporal lobectomy. Recent investigations using laboratory tests of memory have reported an association between the neuropathological status of the resected left mesial temporal region and memory outcome, with adverse memory outcome associated with a lack of significant left Hippocampal pathology. The purpose of this investigation was to examine the relationship between the reports by the patients and their families of observed postoperative changes in day-to-day memory function and the degree of Hippocampal Sclerosis in resected left mesial temporal lobes. Twenty patients and a close family member (parent or spouse) of each of the patients completed standardized questionnaires assessing pre- to postoperative changes in verbal and spatial memory; these were related to the neuropathological findings. The results indicated that patients without left Hippocampal Sclerosis reported significantly worse memory outcome than those with Hippocampal Sclerosis. The ratings provided by the relatives of the patients yielded a comparable effect, and objective memory tests supported the reports by the patients and their families. The neuropsychological findings associated with left Hippocampal pathology are of clinical significance and should be considered in surgical evaluation and in the counseling process.