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ABSTRACT: The aim of this paper is to provide functional results obtained from electrical cortical stimulation of the lower postcentral gyrus in patients who underwent either lesional or non-lesional epilepsy surgery. Group I (n=393) included those patients with gliosis or normal tissue and Group II (n=107) included patients with space-occupying lesions. For cortical stimulation, a unipolar voltage-controlled electrode was used. The tongue, lip, and hand/finger sequences over the lower postcentral gyrus lateromedially in both groups were in agreement with classic teaching. The presence of structural lesions, such as tumors and dysplasia, did not affect the vertical representation of the body parts on the lower sensory strip. Individual variations, which included mosaicism over the sensory strip, were frequent. Whether the functional variability and mosaicism within the sensory cortex result from a pathological condition or not remains to be elucidated in healthy humans using advanced non-invasive brain mapping techniques.
Journal of Clinical Neuroscience 07/2009; 16(9):1188-94. · 1.25 Impact Factor
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ABSTRACT: Language lateralization and factors that may influence language lateralization were investigated using positron emission tomography.
Ninety-two right-handed patients who had left-sided lesions (tumors, focal cortical dysplasia, and vascular lesions) and 19 right-handed normal subjects were included and synonym generation task was used for evaluation of language lateralization.
As expected, the majority of individuals in both groups showed left hemisphere dominance. Lesions in the vicinity of language-related areas did not alter patterns of activation responses. However, atypical inferior frontal gyrus (IFG) activations (33.6%) were more commonly observed in the patient group than in the control group (21%). There were no clear right-sided IFG activations in the control group but almost 28% of the patients showed clear right-sided IFG activations. Atypical language lateralization was strongly correlated with duration of seizure (p = 0.01) and early age at onset (p = 0.03).
Our data provide evidence for inter-hemispheric plasticity related to language function as a response to lesions involving the left hemisphere. A better understanding of the dynamic organization of the brain and about the interaction between the lesion and reactional plasticity will lead to changes in surgical strategy, which will enable us to perform a total removal of the lesion involving eloquent brain areas with improved functional outcome.
Acta Neurochirurgica 06/2009; 151(10):1175-90. · 1.52 Impact Factor
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ABSTRACT: To provide information related to atypical language activations (right or bilateral) in positron emission tomography in patients with left clear-cut hippocampal sclerosis. MATERIAL and
Twelve right-handed patients who had been operated on left-sided hippocampal sclerosis and 12 right-handed normal subjects were included and the synonym generation task was used for evaluation of language lateralization.
Atypical language activations were frequently found in the patients compared to the controls. A total of 3 (25%) subjects in the controls showed atypical activations: 2 bilateral with right and 1 bilateral with left-sided activations. There were no clear right-sided Broca activations in the control group but almost 25% of the patients showed clear right-sided Broca activations. In the patients the incidence of atypical language activations was 91.6% (11 patients).
From the present study, it is clear that functional reorganization of the language-related neuronal network is modified in patients with left hippocampal sclerosis. Although the lesion is far from the primary language-related areas, atypical language lateralization is common in these patients and this should be considered in preoperative period.
Turkish neurosurgery 02/2009; 19(1):1-14. · 0.62 Impact Factor
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ABSTRACT: In this paper the authors aimed to provide information related to major and minor surgical and neurological complications encountered following stereoelectroencephalography and epilepsy surgery.Methods The authors performed a retrospective review of 491 and 1905 patients who underwent intracranial electrode implantation and epilepsy surgery, respectively, between 1976 and 2006 at the Montreal Neurological Institute. All intracranial electrode implantations and surgical procedures were performed by 1 surgeon (A.O.).
A total of 6415 electrode implantations and 2449 surgical procedures were done. There were no deaths related to either procedure. There were no major complications after intracranial electrode implantation, and the risks of infection and intracranial hematoma were found to be 1.8 and 0.8%, respectively. The number of electrodes per lobe (p = 0.05) and number of lobes covered (p = 0.04) were significant risk factors for hematoma and infection. Regarding epilepsy surgery, there were no major surgical complications, and the overall minor complication rate was 2.9%. Infection was the most common complication (1.0%), followed by intracranial hematoma (0.7%). Significant risk factors associated with hematomas and infections were the number of reoperations (p = 0.001) and older patient age (p = 0.03). Minor and major neurological complication rates were 2.7 and 0.5%, respectively, and the rate of overall neurological morbidity was 3.3%. Hemiparesis was the most frequent neurological complication (1.5%).
Based on the authors' experience, intracranial electrode implantation is an effective method with an extremely low morbidity rate. Moreover, epilepsy surgery is safe, especially in experienced hands.
Journal of Neurosurgery 02/2009; 110(6):1111-23. · 2.96 Impact Factor
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ABSTRACT: Superficial anastomotic veins (SAVs) have been studied extensively but little attention has been paid to clinical studies. The aim of this study is to provide variations in the drainage patterns of SAVs depending on the intraoperative findings.
A total of 251 craniotomies due to intractable temporal lobe epilepsy were performed between 1972 and 1987 at the Montreal Neurological Institute. The courses of the three largest SAVs including the vein of Trolard (VT), vein of Labbe (VL) and superficial Sylvian vein (SSV) were studied.
All three veins showed variable courses. The most common predominant vein was the combination of the VL + SSV. The VT and VL were frequently coursed at the level of the central vein and middle temporal vein, respectively. On the right hemisphere the SSV was the predominant type while the VL tended to be predominant on the left hemisphere. A combination of VL and SSV was predominant in patients with right and/or left hemispheric dominance.
The SAVs showed considerable variation in their courses and it is difficult to define an exact pattern although some courses showed constant directions. Attention should be paid not to damage these veins since in a considerable number of cases a single dominant vein may be responsible for draining a majority of the lateral surface of cerebral hemisphere.
The Canadian journal of neurological sciences. Le journal canadien des sciences neurologiques 02/2009; 36(1):65-71. · 0.97 Impact Factor
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ABSTRACT: It has been suggested that aim of the temporal lobe epilepsy surgery is twofold: first is to decrease seizure frequency and second is to improve quality of life without causing intolerable complications. The aim of this prospective, longitudinal clinical study is to report outcomes with respect to seizure, medication, employment and quality of life in short- and long-term follow-ups after resective temporal lobe epilepsy surgery. Consecutively 63 patients who underwent resective temporal lobe epilepsy surgery between 1993 and 1994 were enrolled. Outcomes at 6 months, 2 and 12 years were evaluated and compared with pre-operative status. The mean follow-up of this study was 12.3+/-0.6 years. Results showed that rates of seizure freedom were 82.5, 76.2, and 70.8% at 6 months, 2 and 12 years, respectively. Significant reduction in antiepileptic drug dose at long-term follow-up was found when compared to baseline. Patients after surgery had net gain of employment and improved quality of life was seen in all seizure outcome groups after surgery. Seizure-free patients showed better quality of life than those who continued to have seizure. Our results suggest that surgery leads to improvement in both seizure outcome and quality of life. Even years after the surgery, patients are still working, have reduced their medication load and have nearly normal life.
Seizure 07/2008; 17(4):339-49. · 1.80 Impact Factor
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ABSTRACT: The purpose of this prospective work was to evaluate the relationship between seizure outcome and psychosocial status in patients who underwent temporal lobe epilepsy surgery for medically intractable seizure.
The Liverpool Psychosocial Battery, which includes physical, social, and psychological domains, was completed by 63 patients with temporal lobe epilepsy before surgery, as well as 6 months and 2 years after surgery. The differences regarding the Liverpool Psychosocial Battery domains were compared between seizure-free and nonseizure-free patients at 6 months and 2 years after surgery. Serial follow-up results were also compared with the baseline.
On all measures, patients showed significantly better scores after surgery compared with the baseline (P < 0.05). Although seizure-free patients showed improved "psychosocial" outcome over those who continued to have seizures, the differences did not reach a significant level on social and psychological domains.
Surgery has significantly positive effects on psychosocial outcome in patients with temporal lobe epilepsy. However, positive psychosocial changes are not limited to those patients who became seizure free after surgery.
Neurosurgery 05/2008; 62(5):1071-8; discussion 1078-9. · 2.79 Impact Factor
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ABSTRACT: The purpose of this prospective clinical study was to examine the short- and long-term psychosocial outcomes of a consecutive series of patients who underwent extratemporal lobe resection due to medically-refractory epilepsy.
The sample consisted of 23 consecutive patients and all patients completed a questionnaire assessing especially psychosocial outcome 6 months and 2 years after surgery. Results obtained at short- and long-term follow-ups were compared to baseline. Furthermore, the impact of seizure freedom on the psychosocial outcome was sought.
The results suggested that, psychosocial outcome was improved after surgery compared to preoperative status regardless of seizure status. At long-term follow-up, significant improvements were found in social and psychological variables (p < 0.05). Levels of side effects from medication were high at long-term compared to baseline (p = 0.003). Seizure free patients showed better psychosocial outcome than those who had seizure during the postoperative period, however; only the "impact of epilepsy" scale showed significant improvement at 6 months after surgery (p = 0.02).
These results provide evidence that surgery caused appreciable improvements in psychosocial well-being, however; seizure freedom is not key to improving the psychosocial life of patients who have undergone extratemporal lobe epilepsy surgery.
Turkish neurosurgery 04/2008; 18(2):114-24. · 0.62 Impact Factor
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ABSTRACT: Resection strategies for the treatment of temporal lobe epilepsy (TLE) are a matter of discussion, and little information is available. The aim of this study was to compare seizure outcomes at the 5-year follow-up in patients with medically refractory unilateral mesial TLE (MTLE) due to hippocampal sclerosis (HS) who were treated using a cortical amygdalohippocampectomy (CorAH) or a selective AH (SelAH).
The authors obtained data from 100 adult patients who underwent surgery for MTLE. Fifty patients underwent a CorAH and 50 underwent an SelAH. Seizure control achieved with each technique was compared using the Engel classification scheme.
Overall, at the 5-year follow-up, favorable (Engel Classes I and II) seizure outcomes were noted in 82 and 90% of patients who had undergone CorAH and SelAH, respectively. Furthermore, 40% of the patients who had undergone a CorAH and 58% of those who had undergone an SelAH were seizure free (Engel Class Ia). There was no statistically significant difference between the 2 surgical approaches in terms of seizure outcome at the 5-year follow-up (p = 0.38).
Both CorAH and SelAH can lead to similar favorable seizure control in patients with MTLE/HS. However, the authors suggest that the transcortical selective approach has the great advantage of minimizing or completely abolishing the impact of dividing several venous and arterial adhesions which are tedious, time consuming, and, at times, associated with some degree of cerebral swelling.
Journal of Neurosurgery 04/2008; 108(3):517-24. · 2.96 Impact Factor
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ABSTRACT: The central area of the brain, including the pre- and post-central gyri with their vascular structures, is one of the most crucial regions to preserve in neurosurgical intervention. The central sulcus is also a landmark of utmost importance for neurosurgeons. Although the arteries supplying the central region have been briefly described, their exact course has not been studied. The aim of the study is to establish the position and course of the central sulcus artery in relation to the central sulcus and its convolutions.
Computer-assisted three-dimensional (3-D) anatomical reconstructions of the central area and of the central sulcus artery were performed with the aid of neuronavigational software in 13 patients operated at the Montreal Neurological Institute (MNI).
The central sulcus artery was coincident with the central sulcus and course(s) was almost similar on both hemispheres.
The knowledge of the exact course of the central sulcus artery is of paramount importance in cases of lesions or epileptic foci involving the central area. 3-D reconstruction with neuronavigation has proven to be a reproducible and reliable technique to provide the surgeon with the necessary surgical topographic anatomy of the central sulcus artery and central area.
Annals of Anatomy - Anatomischer Anzeiger 02/2008; 190(2):146-57. · 1.86 Impact Factor
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ABSTRACT: The purpose of this prospective clinical study was to assess quality of life (QOL) and impact of seizure status on QOL in patients with extratemporal epilepsy after surgery.
Twenty-three consecutive patients who had been operated due to extratemporal epilepsy were included in this study. Quality of Life Inventory in Epilepsy-10 (QOLIE-10) questionnaire was completed by all patients before 6 months and 2 years after surgery. Results obtained from short- and long-term follow-up were compared to baseline. Furthermore, patients who were seizure-free since surgery and those who had seizure were also compared in terms of outcome in QOL after surgery.
All patients showed significantly improved QOL in both short- and long-term follow-ups compared to preoperative status regardless of seizure status (p<0.001). Seizure-free patients showed better QOL than those of patients who continued to have seizure during postoperative period. Furthermore, improved QOL was correlated with seizure status and shorter duration of epilepsy (p=0.001).
Our findings showed that improved QOL is related to postoperative seizure status. However, future clinical studies including larger population of patients with extratemporal epilepsy are required to elucidate the role of other factors.
Clinical Neurology and Neurosurgery 01/2008; 110(1):30-7. · 1.58 Impact Factor
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ABSTRACT: The aim of this study was to compare neuropsychological outcome at 1-year follow-up in patients with medically refractory unilateral mesial temporal lobe epilepsy (MTLE) due to hippocampal sclerosis (HS) treated by a cortico-amygdalohippocampectomy (CAH) or a selective-amygdalohippocampectomy (SAH).
Data for a series of 72 adult patients who underwent surgery for MTLE/HS were evaluated. Thirty-six patients underwent CAH and 36 SAH. All patients underwent neuropsychological evaluation before and 1 year after surgery.
The intelligence quotient increased postoperatively in both surgical groups. Memory evaluation in the CAH group revealed a postoperative decline in nonverbal memory after right-sided resection and a postoperative decline in verbal memory after left-sided resection. In the SAH group, there was a slight postoperative decline only in verbal memory after left-sided resection, but other memory function was well preserved. However, no significant difference was found between two approaches regarding memory. There was no also statistically significant difference between two approaches in terms of seizure outcome at 1-year follow-up.
Our results suggest that in the clinical planning of seizure treatment, the optimal type of surgical approach is dependent on the outcome predictions, rather than on any supposed advantages to postoperative memory function.
Turkish neurosurgery 05/2007; 17(2):91-9. · 0.62 Impact Factor
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ABSTRACT: We evaluated the results of cortical resection of epileptogenic tissue for treatment of intractable porencephaly-related epilepsy.
We examined clinical features, electrophysiological data, surgical findings, and seizure outcomes after cortical resection in eight patients with intractable epilepsy related to porencephalic cysts.
All eight patients had hemiparesis. Five retained motor function in the hemiparetic extremities; six retained visual fields. All had partial seizures, six with secondary generalization. Seven patients had simple and three had complex partial seizures (CPSs); two also had drop attacks. Four patients had multiple seizure types. Long-term scalp video-EEG (LVEEG) localized interictal epileptic abnormalities that anatomically corresponded to the cyst location in three patients. LVEEG recorded ictal-onset zones in five; these anatomically corresponded to the cyst location in three of the five. EEG recorded generalized seizures in two patients, hemispheric in one, and multifocal in two. Intraoperative electrocorticography (ECoG) revealed interictal epileptic areas extending beyond the margins of the cyst in seven patients. We resected ECoG-localized interictal epileptic areas completely in five patients and partially in two. Cortical resection was based on seizure semiology and LVEEG in one patient whose ECoG showed no epileptiform discharges. After a minimum follow-up of 1 year, six patients had excellent seizure outcome (Engel class I), and two had a >90% seizure reduction (Engel class III) without complications.
Cortical resection guided by ECoG allows preservation of motor function and visual field and provides an effective surgical procedure for treatment of intractable epilepsy secondary to porencephaly.
Epilepsia 02/2005; 46(1):76-83. · 3.96 Impact Factor
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ABSTRACT: 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.
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.
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 > or = 2 years, four (80%) of five patients were seizure free, while the fifth showed lesser improvement (class III).
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.
Epilepsia 07/2004; 45(7):792-802. · 3.96 Impact Factor
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ABSTRACT: Taylor's focal cortical dysplasia corresponds to a localized disruption of the normal cortical lamination with an excess of large, aberrant cells. Sustained epileptic discharges originate from the dysplastic neocortex and this tissue retains sufficient connectivity for expressing seizure abnormalities. In this brief review, we summarize the findings obtained by analyzing surgically-resected human tissue with focal cortical dysplasia that was maintained in vitro in a brain slice preparation. These data have been compared with those obtained from human cortex with normal structural organization; such tissue was available from patients undergoing surgery for a variety of neurological disorders, most often for mesial temporal lobe epilepsy. These studies have shown that: (i). slices obtained from focal cortical dysplastic tissue have an intrinsic ability to generate ictal-like epileptiform events when challenged with the convulsant drug 4-aminopyridine; (ii). 4-aminopyridine-induced ictal discharges are not seen in neocortical slices obtained from neocortical samples with no or minimal structural lesion; (iii). these ictal discharges are caused by the activation of excitatory amino acid receptors, and in particular those of the N-methyl-D aspartate type; (iv). focal cortical dysplastic tissue also generates synchronous potentials that are mainly contributed by GABA(A) receptor-mediated conductances.
Epileptic disorders: international epilepsy journal with videotape 10/2003; 5 Suppl 2:S45-50. · 1.50 Impact Factor
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ABSTRACT: We compared the ability of proton magnetic resonance spectroscopic imaging ((1)H-MRSI) measures with that of standard clinicopathological measures to predict length of survival in patients with supratentorial gliomas.
We developed two sets of leave-one-out logistic regression models based on either 1) intratumoral (1)H-MRSI features, including maximum values of a) choline and b) lactate-lipid, c) number of (1)H-MRSI voxels with low N-acetyl group values, and d) number of (1)H-MRSI voxels with high lactate-lipid values, all (a-d) of which were normalized to creatine in normal-appearing brain, or 2) standard clinicopathological features, including a) tumor histopathological grade, b) patient age, c) performance of surgical debulking, and d) tumor diagnosis (i.e., oligodendroglioma, astrocytoma). We assessed the accuracy of these two models in predicting patient survival for 6, 12, 24, and 48 months by performing receiver operating characteristic curve analysis. Cox proportional hazards analysis was performed to assess the extent to which patient survival could be explained by the above predictors. We then performed a series of leave-one-out linear multiple regression analyses to determine how well patient survival could be predicted in a continuous fashion.
The results of using the models based on (1)H-MRSI and clinicopathological features were equally good, accounting for 81 and 64% of the variability (r(2)) in patients' actual survival durations. All features except number of (1)H-MRSI voxels with lactate-lipid/creatine values of at least 1 were significant predictors of survival in the (1)H-MRSI model. Two features (tumor grade and debulking) were found to be significant predictors in the clinicopathological model. Survival as a continuous variable was predicted accurately on the basis of the (1)H-MRSI data (r = 0.77, P < 0.001; median prediction error, 1.7 mo).
Our results suggest that appropriate analysis of (1)H-MRSI data can predict survival in patients with supratentorial gliomas at least as accurately as data derived from more invasive clinicopathological features.
Neurosurgery 09/2003; 53(3):565-74; discussion 574-6. · 2.79 Impact Factor
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ABSTRACT: Tumors of glial origin such as glioblastoma multiforme (GBM) comprise the majority of human brain tumors. Patients with GBM have a very poor survival rate, with an average life expectancy of <1 year. We asked whether we could identify a survival pathway in high-grade glioma and oligodendroglioma cells that when suppressed, would induce apoptosis of these tumor cells but not of normal human adult astrocytes. To identify these pathways, we selectively suppressed the activity of a number of proteins (Ras, Rac1, Akt1, RhoA, c-jun, and MEK1/2) hypothesized to play roles in cell survival. We found that suppression of Rac1, a small GTP-binding protein, inhibited survival and produced apoptosis in three human glioma cell lines (U87, U343, and U373). Serum induced the activity of Rac1 and the activity or phosphorylation state of p21-activated kinase 1 and c-Jun NH(2)-terminal kinase (JNK), two intracellular targets of Rac1. Suppression of Rac1 also induced apoptosis in 19 of 21 short-term cultures of human primary cells from grades II and III oligodendroglioma and grade IV glioblastoma that varied in p53, epidermal growth factor receptor, epidermal growth factor receptor vIII, MDM2, and p16/p19 mutational or amplification status. In contrast, inhibition of Rac1 activity did not induce apoptosis of normal primary human adult astrocytes. In both established glioma cell lines and primary glioma cells, apoptosis induced by the inhibition of Rac was partially rescued by activated mitogen-activated protein kinase kinase 1, an activator of JNK, suggesting that JNK functions downstream of Rac1 in glioma cells. These results indicate that Rac1 regulates a major survival pathway in most glioma cells, and that suppression of Rac1 activity stimulates the death of virtually all glioma cells, regardless of their mutational status. Agents that suppress Rac1 activity may therefore be useful therapeutic treatments for malignant gliomas.
Cancer Research 04/2002; 62(7):2131-40. · 7.86 Impact Factor
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ABSTRACT: Cortical dysplasia is found in many cases of intractable epilepsy. Dr. Avoli reports that dysplastic cortex--removed from human brains during seizure surgery--shows abnormal excitability in vitro.
Advances in experimental medicine and biology 02/2002; 497:123-32. · 1.09 Impact Factor
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ABSTRACT: In many patients, focal cortical dysplasia (FCD) is characterized by minor structural changes that may go unrecognized by standard radiological analysis. To increase the sensitivity of magnetic resonance imaging (MRI) for the detection of subtle lesions of FCD, we developed voxel-based image postprocessing methods, including first-order texture analysis and morphological processing modeled on known MRI features of FCD. We selected 16 patients with histologically proven FCD. Image processing features were calculated over a neighborhood for each voxel in the three-dimensional T1-weighted MRI. Three feature maps were generated: (1) gray matter thickness map to model cortical thickening, (2) gradient map to model blurring of the gray matter–white matter junction, and (3) relative intensity map to model the hyperintense signal within the lesion. Two observers detected lesions on conventional MRI in 8/16 and on ratio maps in 14/16 patients. Sensitivity was 87.5% (14/16) for the ratio maps compared to 50% (8/16) for MRI (p < 0.003). Specificity was 95% (19/20) for ratio maps and 100% (20/20) for MRIs. Cohen's kappa was 0.53 for MRIs, indicating moderate agreement, and 0.83 for ratio maps, indicating strong agreement beyond chance between the 2 observers. The image-processing methods developed in this study improve visual detection of FCD, even in cases where no lesion is obvious on MRI. These techniques could increase the number of patients with partial epilepsy who could benefit from surgery.
Annals of Neurology 04/2001; 49(6):770 - 775. · 11.09 Impact Factor
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ABSTRACT: Focal cortical dysplasia is a frequent cause of medically intractable partial epilepsy. These lesions are being increasingly identified by high quality images provided by magnetic resonance imaging (MRI), resulting in improved seizure control of surgically treated patients. Small dysplastic lesions are often missed by conventional MRI methods. The identification of subtle structural abnormalities by rectilinear slices is often limited by the complex convolutional pattern of the brain. We developed a method of curvilinear reformatting of three-dimensional MRI data that improves the anatomical display of the gyral structure of the hemispheric convexities. It also reduces the asymmetric sampling of gray–white matter that may lead to false-positive results. We present 5 patients in whom conventional two-dimensional and three-dimensional MRI with multiplanar reformatting was initially considered normal. Subsequent studies using curvilinear reformatting identified lesions in all. Four patients underwent surgery with histological diagnosis of focal cortical dysplasia. Three patients are seizure-free and 1 had significant improvement in seizure control. These results indicate that an increase in the detection of subtle focal dysplastic lesions may be accomplished when one improves the anatomical display of the brain gyral structure by performing curvilinear reformatting. Ann Neurol 1999;46:88–94
Annals of Neurology 06/1999; 46(1):88 - 94. · 11.09 Impact Factor
