bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of Functional Changes in the Medial Temporal Region During Intracarotid Amobarbital Procedure by Use of SPECT
Authors: Kim Byung Gon , Lee Sang Kun , woo Nam Hyun , chun Song Ho , Lee Dong Soo 
Published: August 2005

Summary: Purpose: Because the main blood supply to the medial temporal region is through the posterior cerebral artery, the validity of the intracarotid amobarbital procedure (IAP) is still debated. To verify clinical validity of the IAP, we investigated changes in neuronal function in the medial temporal region during IAP. Methods: Brain single photon emission computed tomography (SPECT) was performed during IAP (IAP‐SPECT) in 22 patients with temporal lobe epilepsy (TLE), and regional cerebral blood flow (rCBF) in the medial and lateral temporal regions of interest (ROIs) was measured quantitatively. To determine the distribution of sodium amobarbital, in another 20 patients with TLE, SPECT images were obtained after intracarotid injection of 99mTc‐HMPAO mixed with sodium amobarbital. Results: Mean rCBF was 89.2% in the medial temporal region and 81.6% in the lateral temporal region; in the former region, it was significantly lower than that shown by the results of interictal SPECT (99.1%; p < 0.001). In a few patients, however, rCBF did not decrease in the medial temporal region. In only 25% of patients, the medial temporal region was visualized in SPECT images obtained after intracarotid injection of 99mTc‐HMPAO. Conclusions: The results in this study demonstrate that IAP is valid because the medial temporal region is inactivated in spite of infrequent delivery of sodium amobarbital. We assume that intratemporal diaschisis is operating for the inactivation of neuronal function. IAP‐SPECT with intratemporal ROIs may be useful for monitoring changes in neuronal function in the medial temporal region during IAP.
Criterion‐Based Validity of an Intracarotid Amobarbital Recognition‐Memory Protocol
Authors: McGlone J. , Black S. E. , Evans J. , Parkin A. , Sadler M. , Sita A. , Squires E. , Stuss D. , Wilson B. A. 
Published: August 2005

Summary: Purpose: We tested whether the behavioral components of an Intracarotid Amobarbital Protocol (IAP) had criterion validity. It was hypothesized that a recognition‐memory test designed for intracarotid injections and used to predict the risk of global amnesia before an elective temporal lobectomy should also identify persons who are severely amnesic due to other neurologic causes. Divergent validity predicts that speech tasks would be unaffected by amnesia. Test‐retest reliability also was measured. Methods: Fifteen persons with severe amnesia were administered four alternate forms of a yes/no recognition‐memory protocol and a speech protocol. No drug injection occurred. Standardized neuropsychological tests were used to divide the amnesic group into those with Global Amnesia (i.e., retain no ongoing memories), Severe Amnesia (i.e., memory impaired), and Amnesia Plus (severe amnesia plus other neuropsychologic deficits). Results: Two persons with Global Amnesia obtained scores at or below chance (i.e., failed) on the memory protocol. Unexpectedly, 12 of 13 severely amnesic persons obtained near‐perfect memory scores. Amnesia had no impact on the speech protocol. Pass/Fail outcomes were highly correlated across all four sets. Conclusions: A four‐item IAP memory protocol showed good reliability and criterion validity in identifying the rare condition of Global Amnesia, but it was insensitive to other disabling, severe amnesic disorders. This IAP memory protocol might have validity in predicting a postsurgical Global Amnesic disorder, but it did not identify and therefore could not predict other more common severe amnesic disorders.
A Comprehensive Profile of Clinical, Psychiatric, and Psychosocial Characteristics of Patients with Psychogenic Nonepileptic Seizures
Authors: Ettinger Alan B. , Devinsky Orrin , Weisbrot Deborah M. , Ramakrishna Ravindra K. , Goyal Amit 
Published: August 2005

Summary: Purpose: To attain a comprehensive profile of clinical, psychiatric and psychosocial characteristics of patients with psychogenic nonepileptic seizures (NESs), and to assess the relation of these factors to NES outcome. Methods: We administered a telephone‐based structured questionnaire to 56 patients with NESs (16 male and 40 female patients; mean age, 35 years) at a mean follow‐up time of 18 months after making the diagnosis of NES. Results: Mean age of NES onset was 28 years with a mean duration of 8 years. Episodes resolved in 29 (51.8%) cases, decreased in 24 (42.9%), persisted unchanged in two (3.6%), and increased in frequency in one (1.8%). Thirty (53.6%) patients, including 13 (44.8%) of patients whose NESs resolved, were rehospitalized for NESs or for other symptoms. Twenty‐nine (51.8%) had significant depressive symptoms, 22 (39.3%) had suicidal ideation, and 11 (19.6%) attempted suicide [including 6 (21%) of the patients whose NESs resolved]. Believing the NES diagnosis was associated with resolution or improvement of NES frequency (p < 0.029), whereas anger in response to receiving the diagnosis did not predict a poorer outcome. Patients' perceptions of having good health (p < 0.02) and good occupational functioning (p < 0.04) were highly correlated with NES resolution. Only patients whose episodes resolved were employed at the time of follow‐up. Conclusions: At a mean of 1.5 years, NES outcome was poor, with resolution in only half the group and with frequent rehospitalizations after NES diagnosis, even among patients whose NES resolved. Depressive symptoms, suicidal ideation, and suicide attempts were common. Believing the NES diagnosis and patient perceptions of having good health and good occupational functioning correlated well with NES resolution.
Vigabatrin
Authors: French Jacqueline A. 
Published: August 2005

Summary:Vigabatrin (VGB) is a structural analogue of the inhibitory neurotransmitter γ‐amino butyric acid (GABA), which produces its antiepileptic effect by irreversibly inhibiting the degradative enzyme GABA‐transaminase. This produces an increase in central nervous system (CNS) GABA levels. VGB is among the few antiepileptic drugs (AEDs) that was synthesized with a specific targeted mechanism in mind and was subsequently demonstrated to function by that mechanism. Tiagabine, a GABA reuptake blocker, is the only other “designer drug” among the currently available AEDs. Therefore, VGB is among the few AEDs for which the mechanism of action is well understood. Recently, safety issues have been raised with regard to the use of vigabatrin. This article reviews the mechanism of action, pharmacokinetics, safety, and efficacy of VGB.
Evidence‐based Medicine and Antiepileptic Drugs
Authors: Privitera Michael D. 
Published: August 2005

Summary:Evidence based health care uses systematic literature reviews with statistical strategies like meta‐analysis to aid decision‐making. This information can help clinicians by organizing data and providing up‐to‐date quantitative summaries of efficacy and adverse effects of treatments. Limitations of meta‐analysis include problems inherent in combining data from trials of somewhat different design, choice of appropriate dosages, and summarizing complex questions as a single odds ratios. I summarize the results of a meta‐analysis of the following antiepileptic treatments for partial seizures in adults: gabapentin, lamotrigine, topiramate, tiagabine, valproate and the vagal nerve stimulator. Each treatment was significantly more efficacious than placebo, and there were nonsignificant trends toward differences among the treatments in efficacy and tolerability. Quantitative analysis of adverse effects is presented. Absent the availability of a comprehensive randomized controlled trial for comparison, a rigorously conducted meta‐analysis provides some useful information.
Nonepileptic Uses of Gabapentin
Authors: Magnus Leslie 
Published: August 2005

Summary:For decades, antiepileptic drugs (AEDs) have been used to treat a variety of nonepileptic conditions such as chronic pain, psychiatric disorders, and movement disorders. As indicated by recent published reports, gabapentin, a relatively new AED, is useful for treating a wide range of neurologic and psychiatric conditions. Although its exact mechanism of action has yet to be determined, gabapentin is likely to have multiple effects. Unlike conventional AEDs used to treat non‐epileptic disorders (e.g., carbamazepine, phenytoin, valproate) gabapentin offers the advantages of low toxicity and a favorable side‐effect profile. The largest area of nonepileptic use of gabapentin is neuropathic pain, in which it has demonstrated efficacy in treatment of postherpetic neuralgia, diabetic neuropathy, and trigeminal neuralgia. It has also been reported effective as therapy for several psychiatric disorders, most notably bipolar disorder. In addition, review of the published literature reveals the usefulness of gabapentin in movement disorders, migraine prophylaxis, and cocaine dependence. Future clinical studies will provide further insight into the range of conditions for which gabapentin is effective.
Characteristics of a Unique Visual Field Defect Attributed to Vigabatrin
Authors: Wild J. M. , Martinez C. , Reinshagen G. , Harding G. F. A. 
Published: August 2005

Summary: Purpose: Vigabatrin (VGB) therapy is associated with a loss of peripheral vision. The characteristics and prevalence of VGB‐attributed visual field loss (V‐AVFL) and associated risk factors were evaluated in patients with epilepsy. Methods: The material comprised the visual fields and case notes of 88 patients with suspected V‐AVFL (25 spontaneous reports and 63 cases from an open‐label extension trial) and of 42 patients receiving alternative antiepileptic drugs (AEDs) from a cross‐sectional study. Results: Forty‐two reliable cases of visual field loss could not be assigned to an alternative known cause and were therefore attributed to VGB (13 spontaneous reports and 29 from the open‐label study). All cases except one were asymptomatic. Seven cases of field loss were present in the reference cohort of 42 patients; all cases could be attributed to a known aetiology. Thirty‐six of the 42 confirmed cases of V‐AVFL exhibited a bilateral defect that was most profound nasally, and three, a concentric constriction. The prevalence of V‐AVFL was 29% (95% confidence interval, 21–39%). Male gender was associated with a 2.1‐fold increased relative risk of V‐AVFL (95% confidence interval, 1.20–4.6%). Age, body weight, duration of epilepsy, and daily dose of VGB, and concomitant AEDs did not predict the occurrence of V‐AVFL. Conclusions: The unique visual field defect attributed to VGB is profound in terms of the frequency of occurrence and the location and severity of loss. The asymptomatic nature of the field loss indicates that V‐AVFL can be elicited only by visual field examination.
Occurrence of Hippocampal Sclerosis: Is One Hemisphere or Gender More Vulnerable?
Authors: Briellmann Regula S. , Jackson Graeme D. , Mitchell L. Anne , Fitt Greg J. , Kim Sung E. , Berkovic Samuel F. 
Published: August 2005

Summary: Purpose: We analyzed a large group of patients investigated for suspected seizures to test whether gender or side are important factors in the origins of hippocampal sclerosis (HS). Methods: We studied 996 consecutive patients (48% men, 52% women) by using standard hippocampal T2‐relaxometry methods. Results: HS was associated with a highly abnormal T2 time (113 ms). Categoric analysis showed that hippocampal T2 time was independent of gender and side. T2 time was bilaterally normal in 81% of men and in 79% of women; it was unilaterally abnormal in 15% of both men and women; and bilaterally abnormal in 4% of men and in 6% of women. Highly abnormal T2 relaxometry, suggesting HS, occurred with equal frequency in men and women and on the right and left sides. Quantitative analysis of hippocampal T2 times showed values not differing significantly between men and women or between the right and left hemispheres. There was no significant interaction between gender and side. Conclusions: In patients with seizure disorders, hippocampal T2 relaxometry is not different in adult men and women and in the right and left hemispheres.
NMDA‐Receptor Activity Visualized with (S)‐[N‐Methyl‐11C]Ketamine and Positron Emission Tomography in Patients with Medial Temporal Lobe Epilepsy
Authors: Kumlien Eva , Hartvig Per , Valind Sven , Øye Ivar , Tedroff Joakim , Långström Bengt 
Published: August 2005

Summary: Purpose: To determine whether neurochemical activation of the N‐methyl‐D‐aspartate (NMDA) receptor‐gated ion channel shows quantitative changes, measured as binding of 11C‐labeled (S)‐[N‐methyl]ketamine, in patients with medial temporal lobe epilepsy (MTLE). Methods: Eight patients with MTLE who were evaluated regarding epilepsy surgery underwent positron emission tomography (PET) with (S)‐[N‐methyl‐11C]ketamine. The presurgical investigations included magnetic resonance imaging (MR1), PET with 18F‐fluoro‐deoxyglucose (18FDG), and seizure monitoring by using video‐EEG. The uptake of (S)‐[N‐methyl‐11C]ketamine in the temporal lobe of ictal onset was compared with the contralateral side and correlated to changes in regional glucose metabolism measured by PET with 18FDG. Results: (S)‐[N‐methyl‐11C]ketamine rapidly reached the brain, and high radioactivities were measured in the striatum, thalamic nuclei, and cortical regions. Overall the brain uptake and regional binding potentials of (S)‐[N‐methyl‐11C]ketamine were similar to measurements observed previously in healthy controls. However, 20 min after administration, when blood flow influence was negligible, a side‐to‐side comparison revealed a 9–34% reduction of tracer radioactivity in the temporal lobes of ictal onset. At earlier times, the differences in binding potentials were less pronounced, 9–21%. The magnitude and distribution of the reduction were similar to the metabolic pattern seen on PET scans with 18FDG. Conclusions: Radioactivity uptake of intravenously administered (S)‐[N‐methy]‐11C]ketamine was reduced in temporal lobes of ictal in patients with TLE. This may reflect reduced NMDA‐receptor density, reduced perfusion, focal atrophy, or other factors.
Age‐Specific N‐Methyl‐D‐Aspartate—Induced Seizures: Perspectives for the West Syndrome Model
Authors: Kábová Radka , Liptáková Soña , Šlamberová Romana , Pometlová Marie , Velíšek Libor 
Published: August 2005

Summary: Purpose: With intraperitoneal N‐methyl‐D‐aspartate (NMDA; 15–200 mg/kg) administration, we attempted to develop an animal model of age‐specific West syndrome to serve for testing of putative anticonvulsant drugs and to determine the mechanisms of this disorder. Methods: Experiments were performed in 12‐, 18‐, and 60‐day‐old (adult) rats. The effects of systemic pretreatment with hydrocortisone (5–25 mg/kg), pyridoxine (20–250 mg/kg), and sodium valproate (VPA; 200 and 400 mg/kg) against the NMDA‐induced automatisms, emprosthotonic (hyperflexion), and clonic‐tonic seizures were determined. NMDA‐induced EEG changes and alterations of the performance in horizontal bar, rotorod, open field, and elevated plus‐maze tests were recorded. Results: In young rats, hydrocortisone had proconvulsant effects. High doses of pyridoxine induced epileptiform activity independent of and distinct from that induced by NMDA. Only VPA had moderate effects against the NMDA‐induced syndrome. EEG consisted of periods of suppression mixed with ictal activity of serrated waves and high‐voltage chaotic EEG activity. In adult rats, EEG alterations involved spike and spike‐and‐wave activity. NMDA also deteriorated performance of young rats in the open field, rotorod, and elevated plus maze tests. Conclusions: NMDA syndrome in rats fulfills some, but not all, criteria of the West syndrome model, such as occurrence of flexion seizures, nonspecific diffuse EEG changes, refractoriness to antiepileptic therapy (but a response to VPA), as well as long‐term alteration of behavioral tasks. However, NMDA‐induced seizures represent an acute model without the occurrence of spontaneous seizures, whereas in the clinical situation, both the seizures and neurologic deterioration are chronic. Further, in the West syndrome and the NMDA seizure model, there is an incongruent response to therapy with antiepileptic drugs.
The Generalized Tonic‐Clonic Seizure in Partial Versus Generalized Epilepsy: Semiologic Differences
Authors: Niaz Faiz E. , Abou‐Khalil Bassel , Fakhoury Toufic 
Published: August 2005

Summary: Purpose: To study differences in the clinical manifestations of generalized tonic‐clonic seizures (GTCS) of partial versus generalized onset. Methods: We studied 10 GTCSs in nine patients with idio‐pathic generalized epilepsy (IGE) and 10 GTCSs in 10 patients with temporal lobe epilepsy (TLE). Videotaped seizures were reviewed for all clinical features, focusing on asymmetries during different phases of each seizure. Results: In the IGE group, focal features were seen before generalized motor activity in seven seizures. The most common was adversive head turn (six seizures). One patient had opposite direction of head turning in two recorded seizures. The tonic phase was always symmetric. In the last generalized clonic phase, asymmetry or asynchrony of motor activity was seen transiently in three seizures. The TLE group showed focal features before generalization in all seizures. Adversive head turning occurred in nine patients and was always contralateral to the focus. Focal clonic activity occurred before generalization in three and was always contralateral to the focus. The generalized tonic phase was usually asymmetric, and in the last clonic phase, motor activity was asymmetric or asynchronous in eight seizures (p > 0.05, IGE vs. TLE). Conclusions: Brief focal features or asymmetry at onset are common in the GTCSs of IGE. However, asymmetry or asynchrony during the last clonic phase are uncommon in IGE, in contrast to TLE.
A Ketogenic Diet Increases the Resistance to Pentylenetetrazole‐Induced Seizures in the Rat
Authors: Bough Kristopher J. , Eagles Douglas A. 
Published: August 2005

Summary: Purpose: The purpose of this study was to test the hypothesis that a ketogenic diet would increase the resistance of rats to pentylenetetrazole (PTZ)‐induced seizures and to understand the relation of ketonemia to seizure resistance. Methods: A freely consumed, high‐fat (ketogenic) diet was administered to male Sprague‐Dawley rats for 5–10 weeks, while control animals were fed either rodent chow or a high‐carbohydrate diet. Ketonemia was measured as plasma levels of β‐hydroxybutyric acid (β‐OHB). Seizures were induced by tail‐vein infusion of pentylenetetrazole. Results: The ketogenic diet produced a highly significant (p <0.01) increase in β‐OHB levels within 5 days. Induction of seizures by PTZ 35 days after animals were placed on their respective diets showed that ketogenic animals had a significantly (p <0.01) increased threshold for seizure induction compared with those fed an isocaloric diet of either high‐carbohydrate or normal rodent chow. Ketogenic animals did not exhibit increased seizure severity relative to controls, despite receiving consistently higher doses of PTZ. Conclusions: The ketogenic diet resulted in an increased seizure threshold, confirming the hypothesis, and seizure threshold was found to be a direct function of the level of ketonemia.
Interictal Spikes Increase Cerebral Glucose Metabolism and Blood Flow: A PET Study
Authors: Bittar R. G. , Andermann F. , Olivier A. , Dubeau F. , Dumoulin S. O. , Pike G. B. , Reutens D. C. 
Published: August 2005

Summary: Purpose: In patients with reflex epilepsy, it is sometimes possible to evoke interictal spikes predictably, thus providing an uncommon but important experimental paradigm for examining the physiological changes produced by epileptiform discharges. Methods: To examine the changes in regional cerebral blood flow (rCBF) and glucose consumption (rCMRglc) produced by interictal spikes, we performed positron emission tomography (PET) scans with the blood‐flow tracer [15O]H2O and with [18F]fluorodeoxyglucose in a patient with fixation‐off epilepsy. The scans were performed in states of high and low spike frequency produced by eye closure and opening, respectively. Results: The rCBF study revealed a focal increase in blood flow associated with the state of increased interictal spiking. The focus was in the posterior portion of the left superior parietal lobule (Talairach coordinates: x: ‐36, y: ‐71, z: 39; t = 4.5; p <0.05) and corresponded to the site of maximal ictal EEG abnormality recorded with implanted electrodes. In a volume of interest of 10‐mm diameter centered on the t statistic peak in the rCBF study, the mean rCMRglc was 39.1 μmol/100 g/min with eyes open and 44.1 μmol/100 g/min (13% increase) with eyes closed. An identical activation paradigm was used in six normal subjects studied with functional magnetic resonance imaging. In the normal subjects, no significant activation was observed in the parieto‐occipital region, indicating that the changes observed in the patient were due to interictal spiking rather than to task performance alone. Conclusions: Interictal spiking produces focal increases in cerebral blood flow and glucose metabolism.
Adjustment of Carbamazepine Dose to Offset the Effects of the Interaction with Remacemide Hydrochloride in a Double‐Blind, Multicentre, Add‐On Drug Trial (CR2237) in Refractory Epilepsy
Authors: Mawer George E. , Jamieson Virginia , Lucas Samuel B. , Wild Janet M. 
Published: August 2005

Summary: Purpose: The efficacy of remacemide hydrochloride (REM) as an antiepileptic drug (AED) was tested in a double‐blind, add‐on trial in patients with refractory epilepsy. Concurrent drugs included carbamazepine (CBZ). The interfering effects of the pharmacokinetic interaction between REM and CBZ were offset by the monitoring of plasma CBZ concentration and the appropriate reduction of CBZ dose by an unblinded observer. Methods: Patients taking CBZ entered a 4‐week run‐in period to stabilise their dosage regimen to Tegretol tablets and blinded capsules containing Tegretol tablets. They then entered an 8‐week baseline period during which variation of plasma CBZ concentration was used to derive an individual Shewart Control Chart for each patient. These charts were used to define the threshold for CBZ dose reduction after the addition of trial drug. Where necessary the unblinded observer adjusted that portion of the daily dose of CBZ concealed in the opaque capsules, thereby maintaining the blind for the investigator and the patient. Results: CBZ dosage reductions ranging from 14 to 50% were required by 63% of patients who received REM. Substantial increases in plasma CBZ concentration, which would have confounded the results of the trial, were thus avoided. The small increases in CBZ concentration that occurred in spite of this procedure were of similar magnitude in responders (patients who experienced ≤50% reduction in seizure frequency during treatment) and nonresponders, and in both groups the mean increase was <1 mg/L. Conclusions: The method is offered as a model solution for problems caused by pharmacokinetic interactions in add‐on trials.