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L M Ojemann

Publications and source records attributed to L M Ojemann.

At least 19 recordsLinked to original sources
PubMed1998

High-resolution inter-ictal SPET and phased-array MRI in partial epilepsy: an imaging comparison with video/EEG and outcome correlation.

To assess the clinical utility of high-resolution inter-ictal single photon emission tomography (SPET) of regional cerebral perfusion and high-resolution magnetic resonance imaging (MRI) of the brain with a phased-array temporal lobe coil, 35 patients with presumed partial epilepsy were evaluated prospectively by these techniques in addition to prolonged video/electroencephalographic (EEG) monitoring. Twenty of these patients had surgical treatment of partial epilepsy with outcome determinations spanning from 12 months to 3 years at follow-up. There were four categories of imaging findings as compared to scalp/sphenoidal EEG localization. Category I included 12 patients (34% of total) in whom there was complete imaging and EEG concordance. Category II included 4 patients (11%) in whom MRI and EEG were concordant but SPET was divergent or normal. Category III included 13 patients (37%) in whom SPET and EEG were concordant but MRI was divergent or normal. Category IV included 4 patients (11%) in whom neither SPET nor MRI was concordant with EEG. In this study, the relative sensitivities of SPET and MRI for localization of partial epilepsy based on prolonged scalp/sphenoidal video/EEG recordings were 76% and 49%, respectively. We conclude that these neuroimaging techniques (phased-array MRI and inter-ictal cerebral perfusion SPET) are complementary and useful in the pre-operative evaluation of patients with partial epilepsy.

Adolescent↗
PubMed1997

Outcome following surgery in patients with bitemporal interictal epileptiform patterns.

We reviewed outcome at least 1 year after temporal lobectomy in 44 patients with bitemporal, independent, interictal epileptiform patterns on EEG. All 44 underwent preoperative intracranial monitoring. Twenty-two (50%) were seizure-free, 14 (32%) had at a least 75% reduction in seizures, and eight (18%) had less than a 75% reduction in seizures. We analyzed age of seizure onset, duration of epilepsy, gender, side of operation, history and clinical findings, findings on MRI, results of intracranial EEG-video monitoring, presence or absence of lateralizing neuropsychological deficits, and pathology of resected tissue to identify factors associated with outcome. Three factors emerged as independently associated with a good outcome: concordance of MRI abnormality and side of operation (p = 0.01), history of febrile seizures (p = 0.04), and 100% lateralization of intracranially recorded ictal onsets to the side of operation (p = 0.05). A seizure-free outcome was much more likely to occur if more than one of these factors was present: with at least two factors co-existing, 83% (15/18) of patients were seizure-free, while only 35% (7/20) were seizure-free with a single factor present (p = 0.0009). Of the six patients without any of the three factors, none were seizure-free. We conclude that it is possible to predict reasonably which patients with bitemporal epileptiform abnormalities will have a good outcome after surgery.

Adolescent↗
PubMed1996

Unilateral focal preponderance of interictal epileptiform discharges as a predictor of seizure origin.

OBJECTIVE: To test the hypothesis that seizure origin may be predicted from scalp-recorded electroencephalographic interictal epileptiform patterns that occur exclusively or preponderantly over a single focal region. PATIENTS AND METHODS: Fifty-nine of 98 patients (>=16 years old) with intractable epilepsy who underwent sphenoidal/scalp electroencephalographic video monitoring were identified as having interictal epileptiform discharges preponderantly (>=75% of all discharges) or exclusively over a single unilateral region (basal-temporal, midposterior temporal, frontopolar, superior frontal, central). Ictal recordings in 48 patients could be interpreted as demonstrating focal origins, and the ictal findings were compared with the interictal findings. Eleven patients had uninterpretable ictal recordings or no seizures during monitoring and were not further considered. RESULTS: All seizures arose from the expected region in 39 of the 48 patients (Fisher's exact test, P<.001). Interictal discharges occurred exclusively over a single region in 23 of the 48 patients, and all seizures arose from the expected region in 22 of the 23 patients (P<.001). Seventeen patients among this group of 23 had exclusively unilateral basal-temporal discharges, and all seizures arose from the expected side, with the exception of one seizure that arose from the opposite side in one patient, with her other seizure arising from the expected side (P<.001). All seizures arose from the expected region in three patients who exhibited all interictal discharges arising from a single superior frontal region, in two patients with discharges only over a single midposterior temporal region, and in one patient with exclusively unilateral frontopolar discharges. CONCLUSIONS: Interictal discharges that demonstrate a consistent unilateral focal preponderance over a single region, regardless of location, generally predict seizure origin. If the discharges are exclusive to a single region, there is a greater than 95% probability that all recorded seizures will originate from the expected region.

Adolescent↗
PubMed1996

Five-year outcome after epilepsy surgery in nonmonitored and monitored surgical candidates.

PURPOSE: We wished to compare outcome 5 years after temporal lobectomy in 28 patients selected for surgery on the basis of interictal EEG patterns with that in 46 patients who underwent EEG-video monitoring studies as part of their preoperative evaluation during the same era. METHODS: The 28 nonmonitored patients had interictal EEG patterns that demonstrated a consistent, unilateral, anterior-midtemporal epileptiform focus, without discordant findings from other studies. Outcomes were assessed for years 4 and 5 after operation. RESULTS: Twenty-six of 28 (92.9%) nonmonitored patients were seizure-free or had at least 75% reduction in seizures. Twenty-nine of 46 (63.0%) monitored patients were seizure-free or had at least 75% reduction in seizures. Preoperative interictal EEGs of 29 of these patients showed independently localized bitemporal, extratemporal, midposterior temporal, or diffuse epileptiform patterns. The remaining 17 monitored patients had preoperative strictly unilateral anterior-midtemporal interictal discharges, and their outcome was comparable to the nonmonitored group, with 15 (88.8%) seizure-free or with at least 75% reduction in seizures. CONCLUSIONS: A proportion of candidates for epilepsy surgery can be selected without ictal recordings provided that interictal EEGs demonstrate consistent unilateral anterior-midtemporal epileptiform discharges and that other data are not discordant.

Adolescent↗
PubMed1993

Phenotypic heterogeneity in families with the myoclonic epilepsy and ragged-red fiber disease point mutation in mitochondrial DNA.

Two families with a point mutation in mtDNA associated with myoclonic epilepsy and ragged-red fiber disease showed pronounced clinical heterogeneity. The mothers of the two families had adult-onset myopathy with ragged-red fibers, partial deficiency of cytochrome c oxidase, and sensory neuropathy. Members of the first family had variable clinical features of progressive ataxic-myoclonic encephalomyopathy and of the other family, primarily adult-onset myopathy. There was a point mutation from A to G at nucleotide pair 8344 located in the tRNALys gene of the mtDNA of all patients tested, three in Family 1, and the mother of Family 2. This clinical heterogeneity may reflect the effects of varying proportions of mutant and wild-type mtDNA in the different organ systems in each individual.

Adenine↗
PubMed1993

Quantitative dendritic and spine analyses of speech cortices: a case study.

The present case study documents an unprecedented opportunity for correlative investigation of brain structure and function by quantitatively investigating the basilar dendritic systems of supragranular pyramidal cells in several cortical areas from a subject who had undergone electrical stimulation mapping 2 years prior to death. Electrical stimulation mapping results provided valuable functional information about the cortical areas removed for postmortem histological analysis. Morphometric analyses distinguished between proximal (first, second, and third order) and ontogenetically later developing distal (fourth order and above) basilar dendritic branches. In general, perisylvian language association stimulation sites (classical Wernicke's and Broca's areas) were characterized by different dendritic patterns than motor strip sites. In primary motor strip tissue blocks, proximal segments were longer than distal segments. In "higher order" elaborative cortical zones, distal segments were longer than proximal segments. Proximal segments outnumbered distal segments in primary motor zones, but the numerical difference between proximal and distal segments was reduced in the association areas. Finally, fourth order segments had significantly more dendritic spines than third order segments in all sites. These dendritic findings suggest a somewhat later ontogenetic development in classical Broca's and Wernicke's areas than in primary motor cortex.

Adult↗
PubMed1993

Seizure outcome in patients undergoing temporal lobe resections for epilepsy.

This article reviews the results of surgical treatment of temporal lobe epilepsy based on retrospective reviews: more recent surveys from 91 centers on the outcomes from the surgical treatment of epilepsy and preliminary data from the authors' institution's 5-year retrospective review of nearly 100 surgical patients matched to medically treated epileptics. Surgical outcomes from resections in other areas, including extratemporal resections, and the efficacy of lesionectomy versus epilepsy surgery for structural lesions are detailed elsewhere in this issue.

Epilepsy, Temporal Lobe↗
PubMed1992

Long-term treatment with gabapentin for partial epilepsy.

Gabapentin was studied as an open-label 'add-on' antiepileptic drug in 35 patients with partial seizures. Follow-up at 6 months, 12 months, 18 months, and 24 months is reported. There was a trend toward improvement in simple (SPS) and complex partial seizures with it reaching significance for SPS at 12 and 24 months and for the weighted combination of seizures at 3 months. Five of nine patients were subsequently successfully converted to gabapentin monotherapy. Of those five, one is now seizure free and three are significantly improved since baseline. One remains with unchanged seizure frequency compared to baseline, but is experiencing less toxicity than at that time. This long-term observation suggests that the short-term effect demonstrated in blinded studies continues and that indeed some patients with refractory epilepsy can be maintained on gabapentin alone. Based on these findings, double-blind monotherapy trials of this drug are presently being conducted.

Acetates↗
PubMed1992

Natural history of drug resistant seizures: clinical aspects.

In an effort to determine the long-term efficacy of surgical therapy for epilepsy, a control group of patients was identified. Both the surgically treated and non-surgical groups were evaluated before and after 5- or 10-year follow-ups for seizure frequency in the preceding 2 years. To date 39 patients have had bona fide partial seizures, with or without secondary generalization, and EEGs with focal epileptiform patterns. Prior to first evaluation, these patients had had seizures for an average of 10 years and were treated with an average of 54 AEDs with documented therapeutic serum levels in most; one-third of the patients participated in experimental studies. After treatment for another 5 years with an average of 2.5 AEDs or 10 years with an average of 4.0 AEDs, no one was seizure free. Fifteen percent had a 75% decrease in seizure frequency and 85% continued to have no significant improvement in seizure control. Thus despite vigorous treatment, these patients who might have been considered surgical candidates continued to have uncontrolled seizures.

Adolescent↗
PubMed1992

Use of psychological and neuropsychological variables in selection of patients for epilepsy surgery.

Cortical resection surgery for epilepsy is costly, involves risk, and does not result in significant seizure relief in a number of patients. Therefore, it is important to develop methods which will as accurately as possible identify in advance those persons who will or will not be helped by this procedure. From a review of the literature and from a presentation of original data, it is concluded that psychological/neuropsychological variables are valid predictors of cessation of seizures following surgery but that they are only infrequently used. A multidisciplinary, multivariate statistical approach, using EEG findings and psychological/neuropsychological variables in combination, provides the most accurate predictions which are superior to those derived from using either EEG variables or psychological/neuropsychological variables alone. This approach also avoids much of the predictive instability encountered when single variables are evaluated. Since psychological/neuropsychological variables are obtained at low cost and are non-invasive, further evaluation of their role as predictors of seizure relief following surgery is needed.

Adolescent↗
PubMed1987

Effect of psychotropic medications on seizure control in patients with epilepsy.

Psychiatric problems are frequently encountered in patients with epilepsy. In an adult clinic population of 2,000 patients, 219 were identified as having been treated with psychotropic medication (PTM). Of these, 59 patients had adequate documentation of seizure frequency 2 months prior to and 2 months during treatment with PTMs. Contrary to many reports, most patients experienced better seizure control on PTM therapy. This demonstrates that most patients will not have an increased frequency of seizures when psychotropic medication is used in low to moderate doses and is introduced slowly.

Adolescent↗
PubMed1986

Comparative pharmacokinetics of zonisamide (CI-912) in epileptic patients on carbamazepine or phenytoin monotherapy.

Zonisamide (CI-912) is an experimental antiepileptic drug. Since this drug is to be evaluated initially as an add-on medication, an investigation was conducted to study its kinetics in the presence of two standard antiepileptic drugs. Patients in two groups, one on maintenance phenytoin (PHT) monotherapy and the other on maintenance carbamazepine (CBZ) monotherapy, each received a single dose of four 100-mg capsules of zonisamide; and blood samples were obtained at periodic intervals. Plasma and red blood cell (RBC) concentrations of zonisamide were measured by high performance liquid chromatography. Plasma and RBC areas under the curve produced by single doses of zonisamide in patients receiving CBZ were significantly higher than those receiving PHT (p less than 0.05). Clearance values, although not statistically significantly different, were lower for the CBZ group; and consistent with this, plasma and RBC concentrations decreased more rapidly in the PHT group. The approximate values for t1/2 were 36.4 h in plasma and 54.2 h in RBC for patients treated with CBZ, and 27.1 h in plasma and 35.8 h in RBC for patients treated with PHT. The RBC/plasma ratio varied eightfold within a given curve. These findings suggest that the dosage of zonisamide in epileptic patients might need to be varied depending on the comedication.

Adolescent↗
PubMed1984

Treatment of epilepsy.

Seizure patterns usually reflect known functions of the involved areas of the brain. The causes of epilepsy vary with the age at onset. For the purposes of determining drug therapy, seizures are divided into three groups. Focal and tonic-clonic seizures respond to one group of drugs, and absence seizures respond to another group. Surgical therapy may be beneficial in some patients with medically intractable epilepsy.

Age Factors↗
PubMed1983

Cinromide in epilepsy: a pilot study.

Monotherapy with the experimental antiepileptic drug cinromide was evaluated in 11 adult outpatients with uncontrolled partial epilepsy. They were treated with phenytoin for 2 months, cinromide for 4 months, and carbamazepine for 4 months. Four patients withdrew from the study during or shortly after crossover to cinromide due to increased seizure frequency or severity. Of the remainder, three preferred carbamazepine, two cinromide, and two phenytoin, based on both seizure control and degree of toxicity. Overall seizure control was not significantly different with any of the three agents, but during cinromide administration secondarily generalized seizure control was uniformly worst and there was also a tendency toward decreased performance on neuropsychological tests. CNS toxicity and gastrointestinal toxicity were prominent during the first month of cinromide treatment, but subsided with time or dose reduction. No abnormalities requiring drug withdrawal were found with laboratory testing. The results suggested, at best, a very limited clinical usefulness for cinromide, and it has been withdrawn from testing by its manufacturer.

Adult↗
PubMed1983

Effect of doxepin on seizure frequency in depressed epileptic patients.

We performed a retrospective study of the effect of antidepressant treatment with doxepin on seizure frequency. From 47 patients treated with doxepin in 3 years, a confirmed seizure disorder and adequate follow-up (mean, 6.8 months) were available for 19 patients. Comparison of mean monthly seizure frequency during equal blocks of time before and during treatment with doxepin in doses of 5 to 400 mg/day demonstrated improved seizure control in 15, no change in 2, and increased seizures in 2 patients. The reduction in seizure frequency may have been a result of a direct antiepileptic effect of doxepin, an indirect effect because of improved affective state, drug interactions, or some combination of these mechanisms.

Adolescent↗