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R Morawetz

Publications and source records attributed to R Morawetz.

At least 19 recordsLinked to original sources
PubMed2005

Racial disparities in the use of surgical treatment for intractable temporal lobe epilepsy.

OBJECTIVE: To compare the use of surgical treatment for epilepsy among different ethnic and racial groups with surgically remediable temporal lobe epilepsy (TLE). METHODS: The authors used multiple logistic regression analysis to model the use of anterior temporal lobectomy in a cross-sectional study of video-EEG monitoring discharge data among residents of Alabama and surrounding states discharged from the University of Alabama at Birmingham Hospital between July 1998 and January 2003 with a primary diagnosis of TLE. RESULTS: Of 432 patients diagnosed with TLE, 130 had evidence of mesial temporal sclerosis on MRI studies. Seventy patients underwent surgery; African Americans were less likely than non-Hispanic whites to undergo surgical treatment (odds ratio, 0.3; 95% CI, 0.2 to 0.8). After potential demographic (age, education, and sex), socioeconomic, medical insurance coverage, and clinical confounders (bitemporal seizure onset) were controlled, African Americans had a 60% less chance to receive surgery than non-Hispanic whites. CONCLUSIONS: There are disparities in the use of surgical treatment for temporal lobe epilepsy. Race appears to be an influential factor related to such disparities.

Adult↗
PubMed2004

Eclampsia, hippocampal sclerosis, and temporal lobe epilepsy: accident or association?

BACKGROUND: Up to 30% of patients with temporal lobe epilepsy (TLE) have no identifiable risk factors. OBJECTIVE: S: To report nine patients with TLE who had a history of eclampsia as the only risk factor for epilepsy and to investigate whether this possible association existed in a larger cohort of women with surgically treated TLE. METHODS: The clinical data, video-EEG, neuroimaging, and neuropathology of 195 consecutive women undergoing anterior temporal lobectomy (ATL) were reviewed. Risk factors for TLE, age at epilepsy onset, and occurrence of pregnancy were identified in each patient. RESULTS: Twenty-six women had no identifiable risk factors or seizures following a pregnancy. Nine of the 26 women had a history of eclampsia. The median age at the time of eclampsia was 16 years, and the latent period between the occurrence of eclampsia and onset of epilepsy ranged from 1 month to 2 years. The clinical, EEG, MRI, and neuropathologic findings were typical of hippocampal sclerosis (HS) and other than age at onset were no different from those of noneclampsia ATL patients. At mean follow-up of 57 months, seven patients were seizure-free and the other two markedly improved. CONCLUSION: Eclampsia may be a risk factor for TLE and HS.

Adolescent↗
PubMed2001

Magnetic resonance spectroscopic imaging in temporal lobe epilepsy: neuronal dysfunction or cell loss?

BACKGROUND: Magnetic resonance spectroscopy (MRS) has demonstrated consistent metabolic abnormalities in temporal lobe epilepsy. The reason for decreases in N-acetylated compounds are thought to be related to neuronal hippocampal cell loss as observed in hippocampal sclerosis. However, mounting evidence suggest that the N-acetylated compound decreases may be functional and reversible. OBJECTIVE: To establish whether the metabolic changes measured by MRS correlate to hippocampal cell loss in temporal lobe epilepsy. SUBJECTS AND METHODS: We prospectively performed quantitative hippocampal MR imaging volumetry and MRS imaging in 33 patients with intractable mesial temporal lobe epilepsy who were undergoing surgery. A neuronal-glial ratio of cornu ammonis and fascia dentata was obtained and correlated while validating the pathologic analysis by comparisons with specimens of age-matched autopsy control-case hippocampus (n = 14). RESULTS: The neuronal-glial ratio of the patient group was statistically significantly lower than in the control group for the cornu ammonis region (P<.001). Correlations of hippocampal volumes with cornu ammonis and neuronal-glial ratios revealed a significant interdependence (P<.01). However, correlations of the resected hippocampal creatine-N-acetylated compound ratio with the cornu ammonis or fascia dentata neuronal-glial ratios showed no significant interdependence (P>.8). CONCLUSIONS: Our findings support the concept that the metabolic dysfunction measured by MRS imaging and the hippocampal volume loss detected by MR imaging volumetry do not have the same neuropathologic basis. These findings suggest that the MRS imaging metabolic measures reflect neuronal and glial dysfunction rather than neuronal cell loss as previously assumed.

Adolescent↗
PubMed2000

Occipitoparietal epilepsy, hippocampal atrophy, and congenital developmental abnormalities.

PURPOSE: Diagnostic uncertainty may arise in patients with occipitoparietal epilepsy when there is neuroimaging evidence of a posterior quadrant lesion and coexistent hippocampal abnormalities ("dual pathology"). It is not known whether hippocampal atrophy (HA) in these patients results from seizure propagation to temporolimbic structures or whether it is part of the pathological process underlying the occipitoparietal epilepsy. Clarification of this issue may have a significant bearing on the management of these patients. METHODS: We studied 20 patients with occipitoparietal epilepsy and neuroimaging or pathologic evidence of a congenital developmental abnormality. Normalized hippocampal volumes were obtained in all patients. The medical records and video-EEG recordings were analyzed to correlate the MRI findings with clinical data, seizure semiology, and EEG findings. RESULTS: HA was found in seven patients (35%). Neuroimaging abnormalities concordant with the side of HA were seen in all cases. There was clinical or EEG evidence of temporal spread in 12 patients. There was no correlation between the presence of HA and temporal lobe spread. The only clinical factor associated with HA in this series was a younger age of seizure onset. CONCLUSIONS: HA in patients with occipitoparietal epilepsy due to congenital developmental abnormalities is most likely to be a marker of a more widespread process related to a common pathogenesis during prenatal or perinatal development. HA in these patients is unlikely to be the result of secondary spread from an extrahippocampal focus. Surgical treatment should be tailored toward the primary epileptogenic zone rather the site of seizure spread.

Adolescent↗
PubMed2000

Predictive value of MRI-identified mesial temporal sclerosis for surgical outcome in temporal lobe epilepsy: an intent-to-treat analysis.

PURPOSE: Magnetic resonance imaging (MRI) accurately identifies mesial temporal sclerosis (MTS), but prediction of successful surgical outcome ranges from 62% to 96% in published studies. Prior investigations only used patients who had received anterior temporal lobectomy (ATL), potentially overestimating the predictive value of MRI-identified MTS (MRI-MTS). METHODS: The authors performed an intent-to-treat analysis of 90 consecutive patients assessed for possible ATL, including 13 who did not undergo ATL because of inconclusive intracranial ictal EEG. Four (31%) of these 13 patients had unilateral mesial temporal abnormalities on their MRIs. RESULTS: The positive predictive value of MRI-MTS for seizure cessation decreased from 0.69 to 0.63 after adjustment for these additional false positive results. Four previous studies had revealed a positive predictive value of 0.75 (0.72 after similar adjustment). CONCLUSIONS: The authors conclude that the predictive value of MRI-MTS for outcome from ATL may be overestimated by small retrospective studies of highly selected postoperative patients.

Adolescent↗
PubMed1999

Subjective versus objective memory change after temporal lobe epilepsy surgery.

OBJECTIVE: To examine subjective versus objective memory change after anterior temporal lobectomy (ATL). METHODS: A prospective, controlled study. Controls included 39 unoperated patients with intractable temporal lobe epilepsy (TLE) who were administered a series of cognitive and health-related quality of life measures at baseline and at 12-month follow-up intervals. The surgery sample included 65 patients with intractable, focal TLE who had undergone either a right or left ATL. These patients were tested preoperatively and at 6-month follow-up intervals. Subjective and objective memory change was quantified using a newly developed methodology to control for practice effect and regression to the mean. RESULTS: Measures of subjective and objective memory change were not significantly related in the surgery sample. Prevalence of significant subjective memory decline 1 year after surgery ranged from 3 to 7%, whereas prevalence of significant objective memory decline ranged from 26 to 55%. Postoperative levels of emotional distress significantly predicted self-reported memory decline 1 year after ATL. Postoperative medication side effect and seizure outcome were also related significantly to subjective memory change in patients who had undergone left ATL. CONCLUSIONS: Subjective and objective memory change after temporal lobectomy are not related. Complaints of significant memory decline after ATL are infrequent and may serve as a marker for depression or other mood disorder rather than organically based memory decline.

Adult↗
PubMed1999

Patient-oriented outcome assessment after temporal lobectomy for refractory epilepsy.

OBJECTIVE: To determine patient-oriented outcome after anterior temporal lobectomy (ATL) for refractory epilepsy. BACKGROUND: Health-related quality of life (HRQOL) is an important component of the assessment of outcome from epilepsy surgery, but prior controlled studies of the effect of surgery on HRQOL are inconclusive. Direct assessment of the effect of surgery on patient concerns of living with epilepsy has not been reported. METHODS: We used reliable and valid instruments to compare HRQOL and patient concerns of 125 patients who had received an ATL more than than one year previously to a clinically similar group of 71 patients who were awaiting ATL. All patients were selected for surgery based on similar criteria. We also used bivariate correlation analysis and multivariate regression modeling to determine the association of traditional outcome variables with HRQOL. RESULTS: Patients who had undergone ATL reported significantly less concern of living with epilepsy in 16 of 20 items of the EFA Concerns Index and better HRQOL in 8 of 11 scales of the Epilepsy Surgery Inventory-55. Regression analysis in the postoperative group demonstrated that mood status, employment, driving, and antiepileptic drug (AED) cessation, but not seizure-free status or IQ, were associated with better HRQOL. CONCLUSIONS: Our findings support a positive affect of ATL on patient concerns and HRQOL in refractory temporal lobe epilepsy, although longitudinal studies are needed to corroborate these results. Mood, employment, driving ability, and AED use are important postoperative predictors of HRQOL.

Adult↗
PubMed1999

Predictive value of 1H MRSI for outcome in temporal lobectomy.

OBJECTIVE: To investigate the predictive value of 1H MRSI for outcome in patients with mesial temporal lobe epilepsy (MTLE). BACKGROUND: 1H MRSI has been shown to be highly sensitive in the lateralization of temporal lob epilepsy. METHODS: The authors analyzed the relationship between the 1H MRSI findings and surgical outcome in 40 consecutive patients who underwent temporal lobe surgery for MTLE. Outcome at a mean of 24 months (range 18 to 40 months) was classified as seizure free or not seizure free. RESULTS: At follow-up, 78% of patients were seizure free. Correlations showed no predictive value for the creatine/N-acetylated compound (Cr/NA) ratio of the operated temporal lobe and outcome. However, a relationship was found between surgical failure and the Cr/NA ratio of the nonoperated temporal lobe and with a Cr/NA ratio in the nonoperated lobe above 1.21 in patients with bilateral abnormalities (p < 0.01). CONCLUSIONS: Preoperative elevations in the Cr/NA ratio in the nonoperated temporal lobe or the presence of higher metabolic ratios contralateral to the proposed surgery are associated with surgical failure. The predictive value of 1H MRSI absolute metabolite concentrations for outcome in MTLE requires further investigation.

Adolescent↗
PubMed1999

Cognitive consequences of coexisting temporal lobe developmental malformations and hippocampal sclerosis.

OBJECTIVE: To characterize patterns of cognitive functioning in a well-defined group of patients with MRI-identified coexisting left temporal lobe developmental malformations (TLDM) and mesial temporal sclerosis (MTS), and to examine neuropsychological outcome in this dual-pathology group following epilepsy surgery. METHODS: Cognitive functioning in patients with left TLDM and MTS (n = 15) was compared with patients with isolated left MTS (n = 40). TLDM and MTS were identified by high-quality MRI protocol. Patients were administered a battery of neuropsychology tests as part of their presurgical workup for possible epilepsy surgery. Unilateral temporal lobe resection was performed on 10 of the dual-pathology patients and 34 of the isolated MTS patients. Postoperative cognitive performance was also assessed. RESULTS: Both groups displayed impairments in verbal and visual memory, language, and academic achievement. Performance on measures of psychometric intelligence, executive function, and attention were not impaired and were similar between groups. Presence of dual pathology was associated with a significantly less efficient verbal encoding strategy on the word list learning task. Postoperatively, declines were noted for both groups across tasks of verbal memory and language. Groups were not different significantly in terms of neuropsychological outcome after surgery. CONCLUSION: Patients with coexisting TLDM and MTS have impaired cognitive functioning similar to MTS patients-in particular, with regard to episodic memory and language deficits. Temporal lobe resection produces similar cognitive changes in both groups.

Adult↗
PubMed1999

Temporal lobe developmental malformations and hippocampal sclerosis: epilepsy surgical outcome.

BACKGROUND: Temporal lobe developmental malformations coexist with mesial temporal sclerosis in the form of dual pathology with a high frequency of bilateral amygdala or hippocampal abnormalities. OBJECTIVE: The aim of this study was to correlate and compare the MRI findings and the surgical outcome in patients with temporal lobe developmental malformations (n = 20) and isolated mesial temporal sclerosis (n = 36). METHODS: MRI-based normalized volumetry of the amygdala and hippocampal formation in patients with unilateral temporal lobe developmental malformations and isolated mesial temporal sclerosis who underwent temporal lobe resections was performed. Seizure outcome was compared between groups at follow-up. RESULTS: The frequency of bilateral hippocampal or amygdala atrophy (p < 0.04) and combined hippocampal-amygdala atrophy (p < 0.02) was higher in patients with temporal lobe developmental malformations. Although no significant difference in postsurgical seizure-free status was found between the temporal lobe developmental malformations and isolated mesial temporal sclerosis groups (70% versus 91%), patients with temporal lobe developmental malformations and bilateral amygdala or hippocampal-amygdala atrophy had a significantly worse outcome (p < 0.02). CONCLUSION: Bilateral hippocampal atrophy is frequent in patients with temporal lobe developmental malformations. However, it is the presence of bilateral amygdala or amygdalo-hippocampal atrophy that is associated with a higher risk of seizure recurrence.

Adolescent↗
PubMed1998

Temporal lobe developmental malformations and epilepsy: dual pathology and bilateral hippocampal abnormalities.

Temporal lobe developmental malformations (TLDM) with focal cortical dysplasia and balloon cells may coexist with mesial temporal sclerosis. The true incidence of this dual pathology is unknown. Our aim was to assess the frequency of amygdala (AM)-hippocampal abnormality in a homogeneous population with this specific developmental malformation. MRI-based volumetry of the AM and hippocampal formation (HF) in 30 patients with unilateral TLDM and intractable partial epilepsy was performed. A volume normalization process defined a normal range of HF and AM volumes in control subjects, and enabled the detection of bilateral volume loss. Normalized volumes detected HF atrophy in 26 patients (nine unilateral and 17 bilateral) and AM atrophy in 18 patients (three unilateral and 15 bilateral). Visual analysis detected unilateral HF abnormality in 21 patients and bilateral abnormality in two. When compared with a group of patients with temporal lobe epilepsy and pure hippocampal sclerosis (N = 92), where volumetry revealed bilateral HF atrophy in 18%, a significant difference in the frequency of bilateral HF atrophy was found (p < 0.0001). Dual pathology is frequent in patients with TLDM (87%), and the AM-HF abnormality is often bilateral (57%). Our data suggest that more widespread and potentially epileptogenic lesions coexist with visibly detectable unilateral TLDM. This has implications for the selection of patients for temporal lobe surgery and may influence surgical strategies.

Adolescent↗
PubMed1998

Amygdala atrophy and seizure outcome after temporal lobe epilepsy surgery.

Surgical outcome in hippocampal atrophy (n = 44) and amygdalohippocampal atrophy (n = 14) were compared. Hippocampal atrophy had better seizure-free outcome than amygdalohippocampal atrophy (80% versus 50%, p = 0.043). Severity of hippocampal atrophy correlated with duration of epilepsy in patients with hippocampal atrophy (r = 0.4, p = 0.007), but not in those with amygdalohippocampal atrophy, suggesting that these two groups may have a different pathogenesis.

Amygdala↗
PubMed1998

Congenital porencephaly: MR features and relationship to hippocampal sclerosis.

PURPOSE: We determined the frequency of amygdalar-hippocampal atrophy in patients with congenital porencephaly-related seizure disorders to ascertain whether specific MR features of the porencephaly correlate with amygdalar-hippocampal atrophy and epilepsy. METHODS: We studied brain MR images of 22 patients with congenital porencephaly and measured the volume of the amygdala, the hippocampal formation, and the porencephalic cyst. We then compared imaging features with seizure symptoms. RESULTS: Porencephaly was unilateral in 20 patients and bilateral in two. Eighteen patients had cortical or subcortical cavitation and four had encephaloclastic changes (noncircumscribed parenchymal destruction associated with cystic components). The porencephaly was located in the middle cerebral artery territory in 12 patients, in the posterior cerebral artery in four, in the internal carotid artery in two, and in multiple vessels in four. The volume of the porencephalic cyst ranged from 1% to 32% of total intracranial volume (mean, 11%). Volumetry detected atrophy of the hippocampal formation in 21 cases (11 unilateral, 10 bilateral) and atrophy of the amygdala in 12 (nine unilateral, three bilateral). No correlation was found between size or location of the porencephaly and degree of hippocampal atrophy. Seizure symptoms correlated with mesial temporal origin but not with cyst location. CONCLUSION: Amygdalar-hippocampal atrophy often coexists with congenital porencephaly (95%), and the atrophy may be bilateral despite unilateral cysts. Hippocampal structures should be carefully assessed in patients with porencephaly-related seizures.

Adolescent↗
PubMed1997

Analysis of granuloma formation in double cytokine-deficient mice reveals a central role for IL-10 in polarizing both T helper cell 1- and T helper cell 2-type cytokine responses in vivo.

In response to i.v.-injected eggs of Schistosoma mansoni, normal mice develop a dominant type 2 response, whereas IL-10-deficient animals generate a mixed type 1/type 2 cytokine profile and show reduced pulmonary granuloma formation. IL-4-deficient mice, while displaying diminished type 2 responses and granulomatous inflammation, also do not fully default to a type 1 cytokine profile. Strikingly, mice doubly deficient in IL-4 and IL-10 are completely defective in pulmonary granuloma formation and develop a highly polarized type 1 cytokine pattern. In analogous fashion, mice deficient in both IL-12 and IL-10 generate highly exacerbated type 2 cytokine responses, whereas in wild-type animals, IL-12 depletion minimally effects egg-induced cytokine production. Together, these results argue first that IL-10 is an important endogenous down-regulator of type 2 as well as type 1 cytokine synthesis, and second, that its induction is critical for type 2 response polarization in vivo.

Animals↗
PubMed1997

Supplementary sensorimotor area epilepsy. Seizure localization, cortical propagation and subcortical activation pathways using ictal SPECT.

We studied clinical signs, EEGs and ictal cerebral blood flow by single-photon emission computed tomography (SPECT) in eight patients with intractable supplementary sensorimotor area (SSMA) seizures. SPECT scans were performed after injection of the regional cerebral blood flow tracer [99mTc]HMPAO (hexametylpropylene amine oxime) early in the ictal phase (2-5 s after seizure onset). Ictal SPECT demonstrated unilateral predominance of hyper-perfusion of the SSMA in all patients, concordant with either lateralizing clinical signs, lateralization of ictal scalp EEG or with the site of ictal onset of seizures, obtained from intracranial electrodes. Two distinctive cortical blood-flow propagation patterns were identified in SSMA seizures. The type I pattern consisted of primary involvement of the ipsilateral SSMA and dorsal premotor and motor cortex. The type II pattern consisted of bilateral but asymmetric mesial frontal propagation. Ictal contraversive head and eye movements were associated with a type I propagation pattern (P < 0.03). Activation of subcortical structures led to variable hyper-perfusion of the basal ganglia and thalamus. Contralateral cerebellar hyperperfusion was observed in all cases. We conclude that ictal SPECT is a useful method for seizure localization in patients with SSMA epilepsy. The observed heterogeneity of clinical features in SSMA epilepsy correlates with propagation to, and activation of, specific cortical structures, and is consistent with known anatomical interconnections between the SSMA, ipsilateral cortical and transcallosal cortical structures.

Adolescent↗
PubMed1997

Association of combined MRI, interictal EEG, and ictal EEG results with outcome and pathology after temporal lobectomy.

PURPOSE: Magnetic resonance imaging, interictal scalp EEG, and ictal scalp EEG each have been shown to localize the primary epileptic region in most patients with mesial-basal temporal lobe epilepsy (MBTLE), but the association of surgical outcome and pathology with each combination of these test results is not known. METHODS: We reviewed the MRI, interictal scalp EEG, and ictal scalp EEG results of 90 consecutive patients with MBTLE. Twelve patients were excluded from the analysis because inconclusive bitemporal intracranial EEG results precluded anterior temporal lobectomy (ATL); none had concordant MRI and interictal scalp EEG results. We compared all combinations of presurgical MRI, interictal EEG, and ictal EEG results to seizure outcome and tissue pathology in the 78 patients who underwent an ATL. RESULTS: Forty-eight (61%) patients had concordant lateralized MRI and interictal EEG temporal lobe abnormalities, with no discordant ictal EEG results; 77% of these patients were seizure-free after ATL. Concordance of MRI and interictal EEG abnormalities correlated with seizure cessation (p < 0.05), compared to all combinations with discordant or nonlateralizing MRI and interictal EEG results. Mesial temporal sclerosis (MTS) was confirmed pathologically in about 80% of both groups (p = 0.5). Outcome in patients with concordant MRI and ictal EEG with nonlateralizing interictal EEG was significantly worse than combinations with concordant MRI and interictal EEG (p < 0.02). CONCLUSIONS: Compared to other combinations of test results, concordance of MRI and interictal EEG is most closely associated with surgical outcome in MBTLE. However, most selected patients have pathologic confirmation of MTS regardless of test results or outcome. This information may be useful for planning the presurgical evaluation of patients with medically intractable MBTLE.

Adolescent↗
PubMed1997

Occipital lobe developmental malformations and epilepsy: clinical spectrum, treatment, and outcome.

PURPOSE: Cortical developmental malformations (CDM) are increasingly recognized in association with epilepsy. We describe 10 patients (age range 14-35 years) with symptomatic occipital lobe epilepsy and CDM. METHODS: Neurologic, neuroophthalmologic and electrophysiologic studies were performed. Patients had MRI, SPECT, and in some cases intracranial EEG investigators. RESULTS: Mean age of seizure onset was 8 years. We noted strong correlations between the presence of visual auras, the scalp EEG pattern, and the subtype of underlying pathology. Magnetic resonance imaging (MRI) showed CDM in all patients, with polymicrogyria and focal dysplasia being the most frequent malformations. Despite the presence of occipital lobe structural malformations in all patients, visual field deficits were present in only 2. Those who underwent cortical resections were seizure-free or showed major improvement at a mean follow-up of 3.5 years. CONCLUSIONS: Intracranial stimulation studies and the low frequency of pre- and postoperative deficits suggest that some degree of cortical visual reorganization may occur in patients with occipital lobe malformations. Occipital lobe CDM should be sought as a cause of symptomatic occipital lobe epilepsy even though they may become symptomatic after childhood.

Adolescent↗