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Ruben I Kuzniecky

Publications and source records attributed to Ruben I Kuzniecky.

At least 19 recordsLinked to original sources
PubMed2006

Race/ethnicity, sex, and socioeconomic status as predictors of outcome after surgery for temporal lobe epilepsy.

BACKGROUND: Several risk factors have been attributed to seizure recurrence after surgery. It is unknown whether race/ethnicity plays a role in outcome. OBJECTIVE: To evaluate whether race/ethnicity plays a role in seizure recurrence after surgery. DESIGN: Cohort study. SETTING: We evaluated data obtained from the epilepsy centers at the University of Alabama at Birmingham and New York University, New York, NY. PATIENTS: All patients included had a diagnosis of mesial temporal sclerosis and underwent temporal lobectomy. MAIN OUTCOME MEASURES: Occurrence of seizure after surgery was registered 1 year after surgery. We used multiple logistic regression analysis to model the presence of seizure recurrence after surgery and generated odds ratios (ORs) for seizure recurrence after surgery for African American and Hispanic patients relative to white patients. An unadjusted model incorporated only race/ethnicity as the independent variable, and an adjusted model included socioeconomic status, age, duration of epilepsy, education, history of febrile seizures, sex, handedness, lateralization of epileptogenic focus, and number of antiepileptics as the independent variables. RESULTS: Two hundred fifty-two patients underwent surgical treatment with pathological confirmation of mesial temporal sclerosis. No differences were found between racial/ethnic groups in terms of seizure recurrence in any models. For African American patients, the ORs were 0.9 (95% confidence interval [CI], 0.4-2.1) for the unadjusted model and 0.8 (95% CI, 0.3-2.0) for the adjusted model; for Hispanic patients, the ORs were 1.6 (95% CI, 0.8-3.2) for the unadjusted model and 1.1 (95% CI, 0.5-2.6) for the adjusted model, relative to white patients. CONCLUSION: Our data suggest that although sex appears to play a role in the outcomes of surgery for temporal lobe epilepsy, race and socioeconomic status do not.

Adult↗
PubMed2006

Magnetic source imaging versus intracranial electroencephalogram in epilepsy surgery: a prospective study.

OBJECTIVE: Noninvasive brain imaging tests can potentially supplement or even replace the use of intracranial electroencephalogram (ICEEG), an invasive, costly procedure used in presurgical epilepsy evaluation. This study prospectively examined the agreement between magnetic source imaging (MSI) and ICEEG localization in epilepsy surgery candidates. METHODS: Patients completing video monitoring with scalp EEG who had intractable partial epilepsy based on ictal electro-clinico-anatomical features were screened. Forty-nine enrolled patients (mean age, 27 years; range, 1-61 years) completed MSI and ICEEG studies. Decisions about ICEEG and surgery were made at a consensus conference where MSI could only influence ICEEG coverage by indicating supplemental coverage to that already planned by an original hypothesis. RESULTS: The positive predictive value of MSI for seizure localization was 82 to 90%, depending on whether computed against ICEEG alone or in combination with surgical outcome. The kappa score of agreement for MSI with ICEEG was 0.2744 (p < 0.01) INTERPRETATION: MSI yields localizing information with a high positive predictive value in epilepsy surgery candidates who typically require ICEEG. This finding suggests that enough clinical validity exists for MSI to potentially replace ICEEG for seizure localization.

Adolescent↗
PubMed2006

Epidural pentobarbital delivery can prevent locally induced neocortical seizures in rats: the prospect of transmeningeal pharmacotherapy for intractable focal epilepsy.

PURPOSE: To determine whether epidural pentobarbital (PB) delivery can prevent and/or terminate neocortical seizures induced by locally administered acetylcholine (Ach) in freely moving rats. METHODS: Rats were implanted permanently with an epidural cup placed over the right parietal cortex with intact dura mater. Epidural screw-electrodes, secured to the cup, recorded local neocortical EEG activity. In the seizure-termination study, Ach was delivered into the epidural cup, and after the development of electrographic and behavioral seizures, the Ach solution was replaced with either PB or artificial cerebrospinal fluid (aCSF; control solution). In the seizure-prevention study, the epidural Ach delivery was preceded by a 10-min exposure of the delivery site to PB or aCSF. Raw EEG recordings, EEG power spectra, and behavioral events were analyzed. RESULTS: Ach-induced EEG seizures associated with convulsions, which were unaffected by epidural aCSF applications, were terminated by epidurally delivered PB within 2-2.5 min. Epidural deliveries of PB before Ach applications completely prevented the development of electrographic and behavioral seizures, whereas similar deliveries of aCSF exerted no influence on the seizure-generating potential of Ach. CONCLUSIONS: This study showed for the first time that epidural AED delivery can prevent, as well as terminate, locally induced neocortical seizures. The findings support the viability of transmeningeal pharmacotherapy for the treatment of intractable neocortical epilepsy.

Acetylcholine↗
PubMed2006

Lafora disease.

Lafora disease (LD) is an autosomal recessive disorder characterized by seizures and progressive neurologic deterioration, and is usually fatal within 10 years of onset. LD is a member of the family of progressive myoclonic epilepsies, which are a heterogeneous group of disorders characterized by myoclonic epilepsy, developmental regression, and associated neurologic symptoms. The following is a report and discussion of a 20-year-old man with no relevant past medical history until the age of 16 years when he had his first generalized tonic-clonic seizure. At a recent medical evaluation, he reported having clusters of generalized tonic-clonic seizure activity 2 to 3 times per week, had recently developed status epilepticus, and was having progressive impairment of cognitive function. The unique clinical elements of LD, including later onset of disease, the excellent initial response to anticonvulsants, and the neurophysiologic clues to the diagnosis are discussed and detailed in relation to this man. Additional research is required to discover a third, unknown locus for LD and to further elucidate the features of the laforin and malin complex-associated pathway. No preventative or curative treatment is currently available for LD and treatment focuses on palliation.

Adolescent↗
PubMed2006

Malformations of cortical development and epilepsy, part 1: diagnosis and classification scheme.

Malformations of cortical development (MCDs) are a common cause of epilepsy, although seizures are not always the most prominent neurologic manifestation of these disorders. In localization-related epilepsy, certain features should create a strong suspicion that an MCD is the underlying cause; these include developmental delay and static focal neurologic deficits, a family history of developmental delay or epilepsy, frequent seizures from onset, and episodes of focal status epilepticus. MCDs can be classified according to a number of different criteria emphasizing clinical phenotype, imaging findings, pathology, or genetic defects. The overall classification of MCDs is based on the 3 fundamental events of cortical formation: 1) proliferation of neurons and glia in the ventricular and subventricular zones; 2) multidirectional migration of immature but postmitotic neurons to the developing cerebral cortex; and 3) cortical organization. Among the most common and distinct syndromes and entities affecting patients with MCDs and epilepsy are focal cortical dysplasia, hemimegalencephaly, tuberous sclerosis, classical lissencephaly, periventricular nodular heterotopia, focal subcortical heterotopia, polymicrogyria, and schizencephaly, all of which are discussed herein.

Cerebral Cortex↗
PubMed2005

Race/ethnicity: a predictor of temporal lobe epilepsy surgery outcome?

PURPOSE: The success of epilepsy surgery in temporal lobe epilepsy reaches a 64% rate of seizure freedom, based on a randomized control trial. Observational studies from epilepsy centers worldwide indicate seizure freedom rates up to 93% when the etiology is unilateral hippocampal sclerosis. Several risk factors are attributed to the recurrence of seizures following the surgical procedure. Nonetheless, whether race influences the outcome of temporal lobe surgery is unknown. The purpose of this study was to evaluate if race plays a role in outcome following surgery. METHODS: Data were obtained from the discharge database of the University of Alabama at Birmingham video/EEG monitoring unit, between 1998 and 2003, as well as the clinical charts. Seizure recurrence was evaluated 1 year following surgery. The sample consisted of all patients with a primary diagnosis of mesial temporal sclerosis (MTS) who underwent anterior temporal lobectomy. Multiple logistic regression analysis was used to model the presence of seizure recurrence after anterior temporal lobectomy for MTS. Two sets of logistic regression models were estimated to generate odds ratios (ORs) for seizure recurrence after an anterior temporal lobectomy for African-Americans or other possible ethnic/racial group present relative to non-Hispanic Caucasians. The first model incorporated only ethnicity as the independent variable and generated unadjusted ORs for seizure recurrence following the surgical procedure. The second set included the independent variables: duration of epilepsy, history of febrile seizures, lateralization of epileptogenic focus, handedness, and age. RESULTS: Seventy patients underwent surgical treatment and all of them had pathologic confirmation of MTS. Follow-up information for six was not available. Analysis of the remaining 64 patients revealed that African-Americans were more likely than non-Hispanic Caucasians to have seizure recurrence after surgery (OR=2.1, 95% CI=0.6-8.0). After potential confounders (duration of epilepsy, history of febrile seizures, lateralization of epileptogenic focus, handedness, and age) were controlled, this finding did not change (OR=1.7, 95% CI=0.3-10.7). CONCLUSION: Our data suggest that race may be an important factor related to seizure outcome following temporal lobectomy.

Adult↗
PubMed2005

Neuroimaging of epilepsy: therapeutic implications.

Neuroimaging has important applications in the diagnosis and treatment of patients with seizures and epilepsy. Having replaced computed tomography (CT) in many situations, MRI is the preferred imaging technique for patients with epilepsy. Advances in radionuclide-based techniques such as single-photon emission CT/positron emission tomography and electromagnetic source imaging with magnetoencephalography are providing new insights into the pathophysiology of epilepsy. In addition, techniques such as magnetic resonance spectroscopy are beginning to impact treatment. In this review, I discuss how these techniques are used in clinical practice but more importantly, how imaging findings play an increasing role in neurotherapeutics.

Epilepsy↗
PubMed2005

Practical strategies for switching to newer antiepileptic drugs.

Traditional antiepileptic drugs (AEDs) are associated with drug interactions and side effects that limit their safety and tolerability. Side effects of traditional AEDs are especially problematic for children and adolescents, women of childbearing age, and the elderly. Many patients with epilepsy may benefit from switching from a traditional AED to a newer agent because the newer agents are generally better tolerated and are less likely to cause drug interactions. Clinical studies have demonstrated improved therapeutic efficiency with better tolerability in patients switching from a traditional AED to lamotrigine, oxcarbazepine, or topiramate monotherapy or combination therapy.

Adult↗
PubMed2004

Cortical reorganization in malformations of cortical development: a magnetoencephalographic study.

BACKGROUND: The evaluation for epilepsy surgery of patients with malformations of cortical development (MCDs) in areas of clinically important cerebral function is a challenge because of the unpredictable localization of critical sensory, motor, and cognitive function. Magnetoencephalography (MEG) source localization of evoked fields can address whether functional reorganization of primary sensory modalities exists in MCDs. METHODS: Consecutive patients with MRI-demonstrated rolandic and calcarine cortex MCDs were identified who had a 148-channel whole-head MEG study to identify the localization of primary somatosensory and visual cortices. Reorganization was considered when localization contrasted that expected upon general anatomic or homuncular rules and was defined against controls. RESULTS: Twelve patients (n = 12) were studied. Six had focal cortical dysplasia, two had polymicrogyria and schizencephaly, and four had isolated polymicrogyria. In the patients with cortical dysplasias, the somatosensory cortices were identified outside the rolandic area. In the two patients with polymicrogyria and schizencephaly, the somatosensory cortices remained in the rolandic areas as long as the anatomy was not distorted by the presence of the schizencephalic cleft. In the patients with isolated polymicrogyria, the somatosensory cortex was mapped without evidence of reorganization. CONCLUSION: In patients with epileptic MCDs involving rolandic and calcarine regions, cortical function may be reorganized if the MCDs are due to an abnormal neuronal or glial proliferation (i.e., cortical dysplasia) but may not be in MCDs caused by abnormal cortical organization (i.e., polymicrogyria).

Adult↗
PubMed2004

Ictal SPECT analysis in epilepsy: subtraction and statistical parametric mapping techniques.

Seizures are associated with an increase in regional cerebral blood flow (rCBF). In partial seizures the increased blood flow closely corresponds with the site of seizure origin. Using tracers that accumulate and remain "fixed" in different areas of the brain proportional to rCBF at the time of injection, ictal SPECT is now an important tool for localization of seizures in a presurgical evaluation. However, the best methods for interpretation of partial seizure-induced changes in rCBF remain unclear. Numerous computer-aided tools have been used to increase objectivity and accuracy of ictal SPECT analysis. This review examines the uses of ictal-interictal subtraction methods and statistical parametric mapping (SPM) to enhance interpretation and utility of ictal SPECT. The review covers the evolution of advanced ictal SPECT imaging analysis techniques and the authors' clinical experience with the use of subtraction and SPM methods. The authors discuss the impact of ictal SPECT subtraction or difference imaging methods and the initial evidence for proof-of-principle that SPM can be used to provide objective, accurate analysis of ictal SPECT scans in patients with temporal and extratemporal lobe epilepsy. The limitations of both methodologies are discussed, and suggestions for further study of validation, improvement, and routine clinical implementation of advanced analysis methods are provided.

Algorithms↗
PubMed2004

Electroclinical and magnetoencephalographic studies in epilepsy patients with polymicrogyria.

RATIONALE: Malformations of cortical development (MCDs) are increasingly recognized as important causes of developmental delay, epilepsy, and other neurological disorders. Polymicrogyria, a type of MCD, is characterized by many small microgyria separated by shallow sulci, a slightly thick cortex, neuronal heterotopia and often enlarged ventricles. The present descriptive study analysis the electroclinical and magnetoencephalographic findings of patients with epilepsy and polymicrogyria without schizencephaly. METHODS: We studied six patients; mean age was 27 years, who had evidence of polymicrogyria in neuroimaging studies. A single equivalent-current dipole (ECD) model was used to estimate the location of epileptiform spike dipole sources. Analysis was performed on selected data segments containing MEG spikes. MEG results were combined with MRI to create magnetic source images (MSI). RESULTS: In all cases we present results of MRI, MEG, Video-EEG monitoring, and other functional neuroimaging studies if performed. CONCLUSIONS: MSI can be used to accurately localize sources of epileptiform discharges. As such MSI can play a role of directly determining the functional epileptogenic significance of abnormalities depicted in imaging.

Adolescent↗
PubMed2004

Ictal single-photon emission computed tomography imaging in extra temporal lobe epilepsy using statistical parametric mapping.

PURPOSE: To examine the application of statistical parametric mapping (SPM) to analyze ictal single-photon emission computed tomography (SPECT) scans in surgical candidates with extratemporal lobe epilepsy. METHODS: The authors selected patients who underwent successful ictal SPECT acquisition in the process of surgical treatment of intractable partial epilepsy. Thirteen patients were identified who met inclusion criteria for confident seizure localization from either intracranial electroencephalogram recordings or epilepsy surgery outcome. In these cases, ictal scans were registered to an in-house-developed normal SPECT atlas composed of 14 spatially normalized brains of normal subjects. SPM96 was used to test on a voxel-by-voxel basis for statistically significant increases in blood flow associated with each patient's ictal scan. The results were then mapped back onto the patient's magnetic resonance image (MRI) for final interpretation. Statistical parametric mapping (SPM) analysis of ictal SPECT scans was compared to both conventional visual interpretation and the analysis of subtraction ictal SPECT co-registered to MRI (SISCOM). RESULTS: Ten of 13 patient scans showed localizing focal ictal increases in regional cerebral blood flow, all of which were concordant with ultimate epilepsy localization. Of the 3 cases not localized with SPM, 1 was localized by conventional visual interpretation and another, not localized by visual interpretation, was correctly localized with SISCOM. Two cases not localized by SISCOM were localized by both visual and SPM analysis. CONCLUSIONS: This work provides supportive evidence for proof of principle that SPM can be used to provide objective, accurate analysis of ictal SPECT scans in patients with extratemporal lobe epilepsy.

Adolescent↗
PubMed2004

Neuroimaging of epilepsy: advances and practical applications.

The role of modern neuroimaging in the management and treatment of patients with seizures and epilepsy continues to expand at a rapid pace. Magnetic resonance imaging (MRI) is now well established as the imaging technique of choice for patients with epilepsy, but new MR-based techniques, such as MR spectroscopy, functional (f)MRI, and fMRI/electroencephalogram, are more frequently being used to increase the yield of MRI in detecting abnormalities associated with epilepsy. In parallel, advances in radioactive-based techniques, such as single photon emission computed tomography, positron emission tomography, and magnetic source imaging, are improving the localization power of these techniques in candidates for epilepsy surgery. Advances in computer power are making possible the co-egistration in space of structural and functional information, thus improving the yield for the detection of lesions associated with epilepsy.

Brain↗
PubMed2003

Evolving antiepileptic drug treatment in juvenile myoclonic epilepsy.

BACKGROUND: In the face of availability of newer antiepileptic drugs (AEDs) such as lamotrigine and topiramate, there is need to reassess the role of older AEDs in the treatment of juvenile myoclonic epilepsy (JME). OBJECTIVES: To explore whether lamotrigine and topiramate monotherapy or polytherapy can be effective options in the treatment of JME, and to determine whether older AEDs, such as phenytoin and carbamazepine, have a role in the treatment of JME. DESIGN: A retrospective cohort study. SETTING: A large academic teaching hospital. PATIENTS: Seventy-two consecutive JME patients treated with valproic acid, lamotrigine, topiramate, phenytoin, or carbamazepine between April 1, 1991, and March 31, 2001. METHODS: We compared the efficacy of valproic acid, lamotrigine, and topiramate monotherapy or polytherapy in the control of different seizure types of JME, and compared their efficacy and tolerability with the efficacy and tolerability of phenytoin and carbamazepine. RESULTS: Seizure outcome did not differ when patients receiving valproic acid monotherapy (n = 36) were compared with those receiving lamotrigine monotherapy (n = 14), and when patients receiving valproic acid polytherapy (n = 22) were compared with those receiving lamotrigine polytherapy (n = 21) or topiramate polytherapy (n = 15) (P>.05 for all). The combined data of myoclonic seizure control by all 3 AEDs were poorer when compared with the combined data of generalized tonic-clonic seizure control by all 3 AEDs (P =.03), but not when compared with the combined data of absence seizure control by all 3 AEDs (P =.43). Valproic acid, lamotrigine, and topiramate, when compared with phenytoin or carbamazepine, demonstrated significantly better control of myoclonic seizures (P<.01 for all), but not of generalized tonic-clonic seizures (P>.11 for all). CONCLUSIONS: Lamotrigine and topiramate are effective alternative options to valproic acid in the treatment of JME. Lamotrigine is an effective option as monotherapy and polytherapy. Topiramate is an effective option as polytherapy, but more data are needed to determine if it is an effective option as monotherapy. More effective therapy is needed to improve myoclonic seizure control. Older AEDs, such as phenytoin and carbamazepine, may not be indicated in JME patients.

Adult↗
PubMed2003

Significance of fornix atrophy in temporal lobe epilepsy surgery outcome.

BACKGROUND: Previous magnetic resonance imaging (MRI) studies have shown concurrent fornix atrophy in a large proportion of patients with hippocampal atrophy. The contribution of the fornix as an independent preoperative determinant of surgical outcome is unknown. OBJECTIVE: To evaluate the contribution of the fornix as a determinant of surgical outcome in patients with preoperatively determined temporal lobe epilepsy. METHODS: We selected 78 patients who had undergone anterior temporal lobectomy for intractable temporal lobe epilepsy at the University of Alabama at Birmingham Epilepsy Center during a 24-month period. All patients underwent standard presurgical investigations and intracranial investigations when needed. Magnetic resonance imaging volumetric studies were performed prior to surgery using previously published techniques. Patients were assessed regularly for postoperative seizure control. Outcome after at least 3 years was evaluated using Engel's classification for epilepsy. The chi2 test was used to compare categorical data. RESULTS: Seventy-eight patients were included in this study. Eight patients were excluded because of inadequate follow-up. Thirty-five patients (44.9%) had unilateral isolated hippocampal atrophy exclusively on MRI volumetry, 29 (37.2%) had unilateral hippocampal atrophy with ipsilateral fornix atrophy, and 6 (7.7%) had isolated fornix atrophy without hippocampal atrophy. Twenty-eight patients (80%) in the unilateral hippocampal atrophy group were seizure free (ie, Engel class 1: patients who are completely seizure free with no aura and who do not receive antiepileptic drugs) compared with 21 patients (73%) in the fornix and hippocampal atrophy group (P =.57). All 6 patients with isolated fornix atrophy achieved an Engel's class 1 outcome. CONCLUSIONS: These findings suggest that identification of fornix atrophy with or without associated hippocampal atrophy is not an important preoperative determinant of surgical outcome. However, in the presence of a normal hippocampus, fornix atrophy may be valuable in predicting seizure-free outcome.

Adolescent↗
PubMed2003

Confirmation of nonconvulsive limbic status epilepticus with the sodium amytal test.

Is it a seizure? This question can be difficult for a clinician to answer, and it may be more critical if the possible seizure lasts >30 min. Long-duration questionable seizure activity changes the question to, "Is it status epilepticus?" Status epilepticus (SE) can be divided into convulsive and nonconvulsive types. Convulsive SE is the most easily recognized, whereas nonconvulsive SE is more clinically variable and controversial. The term nonconvulsive SE is more often applied to patients who are severely obtunded or comatose with minimal or no motor movements, or in a stupor of altered consciousness reflecting generalized ictal activity. Nonconvulsive SE also can be caused by focal seizure activity, sometimes restricted to deep small volumes of brain in which scalp EEG may not be diagnostic. We present the case of a patient who had dominant limbic hippocampal SE, but in whom the diagnosis could not be confirmed until a modified novel use of the sodium amytal test was performed.

Adult↗
PubMed2003

Stereotactic surgical approach to hypothalamic hamartomas.

Hypothalamic hamartomas are often associated to a progressive epileptic encephalopathy. Non-invasive data indicates that destruction or isolation of the hamartoma may stop seizures. We present data on patients who underwent stereotactic radiofrequency with or without endoscopy. Epilepsy improved in 60% of patients with minimal morbidity. This approach was less successful in large lesions. These results indicate that this approach should be considered in patients with small/medium lesions.

Adolescent↗