Hemicranial volume deficits in patients with temporal lobe epilepsy with and without hippocampal sclerosis

PURPOSE: In patients with refractory temporal lobe epilepsy, studies have suggested volume deficits measured by MRI of brain structures outside the epileptogenic hippocampus. Hippocampal sclerosis (HS) is a frequent, but not obligate, finding in such patients. The present study examines the influence of the presence of HS on quantitative magnetic resonance imaging (MRI) measurements. METHODS: We analyzed 47 patients and 30 controls by quantitative MRI, including intracranial volume (ICV), hemicranial volume, hippocampal volume (HCV), and T2 relaxometry. MRI results were compared with histological findings in the resected temporal lobe. RESULTS: Histology documented HS in 35 patients (HS group) and other findings in 12 patients (no-HS group). In both groups, the hemicranial volume ipsilateral to the epileptogenic focus was significantly smaller than on the contralateral side (p < 0.004). The HCV on both sides was smaller in the HS group compared with patients without HS (p < or = 0.004). Unilateral hippocampal atrophy and increased T2 value were found in 71% of patients with HS, and bilaterally normal HCV and T2 value were found in 67% of patients without HS. CONCLUSIONS: The smaller hemicranial volume on the focus side, irrespective of the presence or absence of HS suggests a different pathogenic mechanism for the additional hemicranial volume deficit, compared to HS itself. The contralateral HCV deficit depends on the presence of HS, indicating a pathogenic connection between damage to both hippocampi.     

Interaction of 4-(n-dimethylaminostyryl)-1-methylpyridinium-n-toluolsulfonate with liposomes: analysis of fluorescence spectra

A previous magnetic resonance imaging study from our laboratory reported significant temporal lobe volume deficits in cortical gray matter, white matter, and anterior hippocampus in chronic alcoholic men relative to controls. In the present study, we reexamined these data and asked whether withdrawal seizure history was predictive of either the hippocampal or the extrahippocampal volume deficits. A review of the medical charts indicated that 11 alcoholics had experienced one or more alcohol-related seizures and 35 were seizure-free; no patient had a seizure disorder unrelated to alcohol. The two alcoholic groups did not differ significantly in age, education, alcohol consumption variables, premorbid intelligence, Memory Quotient, Trail Making, or detection of hidden figures. Although each alcoholic group showed significant bilateral volume deficits of the anterior hippocampus and frontal-parietal and temporal gray matter, relative to controls, the seizure group had significantly smaller temporal lobe white matter volumes than either the control or the seizure-free groups; the latter two groups did not differ from each other. Both alcoholic groups, however, had white matter volume deficits in the frontal-parietal region. Thus, the seizure group accounted for the white matter volume deficits in the temporal lobe previously reported in the full sample of alcoholics. It seems, then, that reduced white matter volume in the temporal lobes may be either a risk factor for or sequela of alcohol withdrawal seizures.     

Anterior temporal abnormality in temporal lobe epilepsy: a quantitative MRI and histopathologic study

OBJECTIVE: To examine the nature and frequency of anterior temporal lobe (AT) abnormalities that occur in intractable temporal lobe epilepsy (TLE). METHODS: We reviewed the MR scans and clinical histories of 50 consecutive patients with intractable TLE. Histopathology was available in 42 surgically treated cases. RESULTS: MRI demonstrated loss of the gray-white matter differentiation and decreased T1- and increased T2-weighted signal in the ipsilateral AT in 58% of the 50 patients. This appearance was observed in 64% of the 36 patients with hippocampal sclerosis (HS) but was also seen in patients without HS. These changes were associated with temporal lobe atrophy, a higher hippocampal T2 relaxation time, and a history of febrile convulsions. Pathologic examination showed that the MRI appearances were not caused by dysplasia, degenerative abnormalities, or inflammatory change. Histologic quantitation showed increased glial cell nuclei counts in the intractable TLE cases compared with controls. There was no difference in glial cell numbers between cases with AT abnormality and those without this appearance. Presence or absence of changes was not predictive of preoperative neuropsychology, postoperative change in neuropsychology, or seizure outcome after surgery. CONCLUSIONS: These frequently seen ipsilateral changes are not caused by gliosis and may reflect a nonspecific increase in water content in the temporal lobe. This may be due to myelin abnormalities or some other as yet unidentified pathologic factor.     

Regional changes in hippocampal T2 relaxation and volume: a quantitative magnetic resonance imaging study of hippocampal sclerosis

OBJECTIVE: The principal MRI features of hippocampal sclerosis are volume loss and increased T2 weighted signal intensity. Minor and localised abnormalities may be overlooked without careful quantitation. Hippocampal T2 relaxation time (HT2) can be quantified, but previously has only been measured on a few thick coronal slices with interslice gaps. In this study HT2 was measured along the entire length of the hippocampus on contiguous slices and used, with quantitative measures of hippocampal volume (HV) and distribution of atrophy, to better define the range of hippocampal sclerosis. METHODS: Thirty patients with temporal lobe epilepsy, 10 patients with extratemporal localisation related epilepsy and extratemporal lesions, and 20 control subjects were studied using MRI T2 relaxometry and volumetry. RESULTS: In controls and patients, HT2 was higher in the anterior than the posterior hippocampus. Using HV, morphometric, and HT2 data, patients with temporal lobe epilepsy were classified as unilateral diffuse hippocampal sclerosis (n=16), unilateral focal (n=6), bilaterally affected (n=6), and normal (n=2). In patients with unilateral hippocampal sclerosis, the anterior hippocampus was always affected. In three patients with normal HV, HT2 measurements disclosed unilateral focal abnormalities that corresponded to the EEG lateralisation of epileptic activity. Patients with bilateral hippocampal involvement had an earlier onset of epilepsy than patients with unilateral hippocampal sclerosis. CONCLUSIONS: Measurement of regional abnormalities of HT2 along the length of the hippocampus provides further refinement to the MRI assessment of the hippocampi in patients with temporal lobe epilepsy and is complementary to volumetric and morphological data.     

"Cavernous sinus EEG": a new method for the preoperative evaluation of temporal lobe epilepsy

PURPOSE: In presurgical evaluation of temporal lobe epilepsy (TLE), invasive methods are necessary if results of various noninvasive methods are not sufficiently convergent enough to identify the epileptogenic area accurately. To detect the epileptiform discharges originating specifically from the mesial temporal lobe, we applied the cavernous sinus catheterization technique. METHODS: We placed Seeker Lite-10 guide wire electrodes into bilateral cavernous sinus through the internal jugular veins to record EEG (cavernous sinus EEG) in 6 patients with intractable TLE. Scalp EEG was simultaneously recorded in all 6 and electrocorticogram (ECoG) was also recorded in 4. RESULTS: The cavernous sinus EEG demonstrated clear epileptiform discharges, sometimes even when they were absent on the simultaneously recorded scalp EEG. The epileptiform discharges recorded from the cavernous sinus electrodes were specifically associated with those in the mesial temporal region on ECoG. Ictal EEG pattern originating from mesial temporal lobe was also clearly documented on the cavernous sinus EEG. CONCLUSIONS: This new, semi-invasive method of identifying epileptogenic areas can detect the epileptiform discharges specifically arising from the mesial temporal lobe; it is as useful as or complements the invasive techniques such as foramen ovale or depth recording.     

Quantitative MRI volume changes in late onset schizophrenia and Alzheimer's disease compared to normal controls

Volumes of medial and lateral temporal lobe structures were assessed using magnetic resonance imaging (MRI) in 11 patients with late-life onset schizophrenia (LOS), 18 normal elderly controls and 12 patients with moderate cognitive impairment due to Alzheimer's disease (AD) who had no non-cognitive symptoms. While both patient groups had smaller volumes of several medial temporal regions (e.g. entorhinal cortex, left hippocampus), schizophrenics had significantly smaller anterior superior temporal gyri (STG) than normal controls, but AD patients did not. We have previously demonstrated anterior STG volume to be reduced in early life onset schizophrenia.     

An evaluation of the marmoset Callithrix jacchus (sagüi) as an experimental model for the dyslipoproteinemia of human Schistosomiasis mansoni

BACKGROUND: There have been only a few brain computed tomography imaging studies, with mostly negative findings, in subjects with borderline personality disorder (BPD). This is the first MRI study which evaluated the structural abnormalities of the brain in subjects with the sole diagnosis of BPD. METHODS: Twenty-five subjects with BPD were compared with age-, gender-matched healthy comparison subjects (n=25) on volumes of the frontal lobes, the temporal lobes, the lateral ventricles, and the cerebral hemispheres in brain magnetic resonance imaging. RESULTS: Subjects with BPD had a significantly smaller frontal lobe compared to comparison subjects (multivariate regression analysis, t=2.225, df=46, P=0.031). There were no significant differences in volumes of the temporal lobes, the lateral ventricles, and the cerebral hemispheres between subjects with and without BPD. LIMITATIONS: Strict inclusion and exclusion criteria employed in the present study may make it difficult to generalize our findings. The gray matter and white matter of the brain were not measured separately. Differences in head tilt during image acquisition were not corrected. CONCLUSIONS: The current study reports a smaller frontal lobe volume on brain MRI in subjects with BPD compared with healthy comparison subjects. This finding may serve as a potentially useful biological variable that may allow for subtyping BPD.     

Language lateralization of Chinese-English bilingual patients with temporal lobe epilepsy: A functional MRI study.

Functional MRI was used to examine language lateralization of Chinese characters and English words associated with temporal lobe epilepsy (TLE) in Chinese-English bilinguals with left or right TLE. The results suggest that the neural basis of processing Chinese and English seems to be different, as normal controls demonstrated left hemispheric lateralization in reading English words but bi-hemispheric lateralization in reading Chinese characters. This difference in the neural bases of Chinese and English processing was found to affect the patterns in change-of-language processing associated with TLE. That is, whereas left-TLE patients were more likely than right-TLE patients to demonstrate a bi-hemispheric language involvement in reading English, both left- and right-TLE patients demonstrated primarily bilateral hemispheric involvement for reading Chinese characters. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Magnetoencephalography in partial epilepsy: clinical yield and localization accuracy

The goals of this study were to determine (1) the yield of magnetoencephalography (MEG) according to epilepsy type, (2) if MEG spike sources colocalize with focal epileptogenic pathology, and (3) if MEG can identify the epileptogenic zone when scalp ictal electroencephalogram (EEG) or magnetic resonance imaging (MRI) fail to localize it. Twenty-two patients with mesial temporal (10 patients), neocortical temporal (3 patients), and extratemporal lobe epilepsy (9 patients) were studied. A 37-channel biomagnetometer was used for simultaneously recording MEG with EEG. During the typical 2-3-hour MEG recording session, interictal epileptiform activity was observed in 16 of 22 patients. MEG localization yield was greater in patients with neocortical epilepsy (92%) than in those with mesial temporal lobe epilepsy (50%). In 5 of 6 patients with focal epileptogenic pathology, MEG spike sources were colocalized with the lesions. In 11 of 12 patients with nonlocalizing (ambiguous abnormalities or normal) MRI, MEG spike sources were localized in the region of the epileptogenic zone as ultimately defined by all clinical and EEG information (including intracranial EEG). In conclusion, MEG can reliably localize sources of spike discharges in patients with temporal and extratemporal lobe epilepsy. MEG sometimes provides noninvasive localization data that are not otherwise available with MRI or conventional scalp ictal EEG.     

Bilateral temporal lobe volume reduction parallels cognitive impairment in progressive aphasia

BACKGROUND: Patients with isolated aphasia in the absence of other cognitive abnormalities have been the focus of several studies during the past decade. It has been called primary progressive aphasia (PPA), and the typical features of this syndrome are marked atrophy of the left temporal lobe according to the radiological examination and a language disorder as the initial symptom. In previous studies of PPA, the selection of the patients was based mainly on linguistic symptoms. Now, when computed tomography or magnetic resonance imaging scans are part of the routine investigation of cognitive impairment and suspected dementia, the patients with lobar atrophy will be found at an earlier stage. In the present study, we used a new approach and defined the study group by selecting patients with obvious left temporal lobe atrophy, assessed by MRI, and we referred to them as patients with temporal lobe atrophy (TLA). OBJECTIVE: To identify the features that distinguish TLA from other primary neurodegenerative disorders. PATIENTS: Six patients with TLA were compared with patients with Alzheimer disease (AD), patients with frontal lobe dementia (FLD), and healthy control subjects. METHODS: The investigations included magnetic resonance imaging volumetry, single photon emission computed tomography, and neuropsychologic and linguistic evaluations. RESULTS: In the TLA group, the mean volume of the left temporal lobe was 35% smaller than the right, while in the AD and FLD groups, the atrophy was symmetrical and bilateral. In the TLA group, the absolute volumes of the temporal lobes were significantly smaller on the left side compared with the AD and FLD groups, whereas there was no difference on the right side. The cerebral blood flow pattern in TLA was asymmetric and differed from that in the other study groups. All patients with TLA had a history of progressive Wernicke-type aphasia, ranging from 2 to 6 years. They showed primary verbal memory impairment but had preserved visuospatial functions. The clinical condition of all patients with TLA deteriorated during the study period; severe aphasia developed, and the patients exhibited signs of frontal lobe dysfunction. Serial volumetric measurements in 4 of 6 patients showed an annual 8% to 9% decrease of both left and right temporal lobes. CONCLUSIONS: The initial marked asymmetry in cognitive function found in patients with TLA contrasts with the general decline found in patients with AD. The bilateral degenerative process evident in patients with TLA paralleled the clinical deterioration, indicating TLA to be a non-AD lobar atrophy that develops into generalized cognitive dysfunction and dementia.     

Photodynamic effect on the specific antitumor immune activity

Patients with mesial temporal lobe epilepsy (MTLE) have asymmetric hippocampal volumes with atrophy that sometimes by visual inspection appears to favor different regions along the longitudinal axis of the affected hippocampus. Histological studies suggest that cell loss may affect the anterior hippocampus preferentially, and that hippocampal sclerosis (HS) limited to the anterior of the hippocampus may indicate better surgical outcome. We used volumetric magnetic resonance imaging (MRI): (1) to objectively describe the distribution of volume loss in HS; and (2) to relate this distribution to outcome of temporal lobectomy. Hippocampal volumes and anterior and posterior subvolumes (AHV, PHV) were measured from MP-RAGE MRI in 43 temporal lobectomy patients with MTLE determined by pathological findings of HS and compared to 23 age-matched controls. Atrophy was defined as 'anterior', 'diffuse', 'posterior', or 'normal' depending on position of AHV and PHV relative to the mean +/- 2 S.D. of regional volumes of control hippocampi. Anterior to posterior ratios (APR = AHV/PHV) were also calculated. Mean APR of hippocampi ipsilateral to lobectomy cannot be distinguished from hippocampi contralateral to lobectomy or from controls. AHV and PHV from hippocampi contralateral to temporal lobectomy were smaller than controls but larger than hippocampi ipsilateral to lobectomy. Surgical outcome was independent of longitudinal distribution of atrophy. We determined that overall volume loss in HS is diffuse, neither clearly favoring the head nor body-tail. Surgical outcome for MTLE is not related to the longitudinal distribution of atrophy revealed by volumetric MRI.     

Assessment of differential attention mechanisms in seizure disorders and schizophrenia.

This study examines differential attention deficits in 19 temporal lobe epilepsy (TLE) patients, 15 generalized seizure patients (GSP), and 19 schizophrenic patients, compared to 20 normal controls. All participants were tested on a variable foreperiod reaction time (RT) task and continuous performance test (CPT). Temporal lobe epilepsy patients and schizophrenic patients show crossover deficits on the RT task requiring a conscious, effortful, preparatory motor set; while GSP show impairments on the CPT requiring vigilant, self-directed attention to external stimuli. The results suggest separate cortical and subcortical brain systems in the respective attentional deficits and in the etiologies of TLE, GSP, and schizophrenic disorders. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Use and misuse of syringes in anaesthesia

OBJECTIVE: To assess whether the cerebral gray and white matter volume deficits described in patients with anorexia nervosa (AN) are fully reversible with weight rehabilitation. DESIGN: A prospective cohort study using magnetic resonance imaging to examine the brains of female adolescents after weight recovery from AN. SETTING: An adolescent eating disorder program located in a tertiary care children's hospital. PARTICIPANTS: Of 13 patients who underwent a previous magnetic resonance imaging study at a low weight, 6 patients were weight recovered and underwent rescanning. All brain measures were corrected for the effects of intracranial volume and age, based on a regression analysis of a group of 34 healthy female control subjects. Scans from the patients with AN were also compared with scans from an age-matched subset of 16 healthy female controls. MAIN OUTCOME MEASURES: White matter volumes, gray matter volumes, and cerebrospinal fluid volumes in the weight-recovered AN group. RESULTS: Quantitative analysis showed that white matter and ventricular cerebrospinal fluid volumes changed significantly (P = .03 for both) on weight recovery from AN. The weight-recovered patients had significant gray matter volume deficits (P = .01) and elevated cerebrospinal fluid volumes (P = .005) compared with those of the age-matched controls. They no longer had significant (P = .30) white matter volume deficits. CONCLUSION: The finding of persistent gray matter volume deficits in patients who have recovered their weight after AN suggests an irreversible component to the structural brain changes associated with AN, in addition to a component that resolves on weight recovery.     

Quantitative brain magnetic resonance imaging in attention-deficit hyperactivity disorder

BACKGROUND: Anatomic magnetic resonance imaging (MRI) studies of attention-deficit hyperactivity disorder (ADHD) have been limited by small samples or measurement of single brain regions. Since the neuropsychological deficits in ADHD implicate a network linking basal ganglia and frontal regions, 12 subcortical and cortical regions and their symmetries were measured to determine if these structures best distinguished ADHD. METHODS: Anatomic brain MRIs for 57 boys with ADHD and 55 healthy matched controls, aged 5 to 18 years, were obtained using a 1.5-T scanner with contiguous 2-mm sections. Volumetric measures of the cerebrum, caudate nucleus, putamen, globus pallidus, amygdala, hippocampus, temporal lobe, cerebellum; a measure of prefrontal cortex; and related right-left asymmetries were examined along with midsagittal area measures of the cerebellum and corpus callosum. Interrater reliabilities were .82 or greater for all MRI measures. RESULTS: Subjects with ADHD had a 4.7% smaller total cerebral volume (P = .02). Analysis of covariance for total cerebral volume demonstrated a significant loss of normal right > left asymmetry in the caudate (P = .006), smaller right globus pallidus (P = .005), smaller right anterior frontal region (P = .02), smaller cerebellum (P = .05), and reversal of normal lateral ventricular asymmetry (P = .03) in the ADHD group. The normal age-related decrease in caudate volume was not seen, and increases in lateral ventricular volumes were significantly diminished in ADHD. CONCLUSION: This first comprehensive morphometric analysis is consistent with hypothesized dysfunction of right-sided prefrontal-striatal systems in ADHD.     

Intact perceptual and conceptual priming in temporal lobe epilepsy: Neuroanatomical and methodological implications.

Explicit memory appears to be supported by medical temporal lobe structures, whereas separate neocortical regions may mediate perceptual and conceptual implicit memory. Children and adults with temporal lobe epilepsy (TLE) and matched controls were administered experimental verbal memory tests. Performance on implicit tests--word identification and word generation--was contrasted with explicit recognition and recall. Encoding conditions emphasized either conceptual or perceptual aspects of study words and were crossed with presentation modality. The priming performance of participants with TLE did not differ from controls, but participants with TLE did show deficits on recognition and recall measures. Thus, intact left temporal cortex does not appear to be necessary for normal implicit memory performance, even when conceptual processing is emphasized at study or test. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

MRI correlates of cognitive impairment in childhood-onset multiple sclerosis.

Objective: Brain MRI measures were correlated with neuropsychological function in 35 pediatric-onset multiple sclerosis (MS) patients and 33 age- and sex-matched healthy controls. Method: Mean age of MS patients was 16.3 ± 2.3 years with average disease duration of 4.3 ± 3.1 years. Cortical gray matter, thalamic, and global brain volumes were calculated for all participants using a scaling factor computed using normalization of atrophy method to normalize total and regional brain volumes for head size. T1- and T2-weighted lesion volumes were calculated for MS patients. Results: Cognitive impairment (CI) was identified in 29% of the MS cohort. Cognitive deficits predominantly involved attention and processing speed, expressive language, and visuomotor integration. Relative to controls, the MS group showed significantly lower thalamic volume (p p p p     

Significance of interictal temporal lobe delta activity for localization of the primary epileptogenic region

Because interictal temporal lobe delta activity (TLDA) has been described in 30 to 90% of patients with temporal lobe epilepsy (TLE) but has not been investigated in patients with extratemporal epilepsy, we sought to determine the localizing significance of TLDA. We compared the presurgical interictal scalp EEG results of 47 consecutive patients who received extratemporal resection (40 frontal and 7 parietal-occipital) for intractable epilepsy with 43 consecutive patients who received anterior temporal lobectomy. We defined lateralized TLDA as runs of lower than 4-Hz waveforms that were easily distinguished from the background rhythms and were maximal at electrodes T4, F8, and T6 or T3, F7, and T5. The lateralized TLDA was subcategorized as temporal intermittent rhythmic delta activity (TIRDA) or temporal intermittent polymorphic delta activity (TIPDA). A chi-square test was used to determine the association of the lobe of the epileptogenic zone with TIRDA and TIPDA. We found TIRDA in 12 (28%) and TIPDA in 8 (19%) patients in the temporal lobe group, and TIRDA in 2 (4%) and TIPDA in 9 (19%) patients in the extratemporal group. TIRDA was strongly associated with TLE (p < 0.003), whereas TIPDA occurred at an equal rate in both groups. Similar to anterior temporal epilepsy, lateralized TIPDA is present in up to 20% of patients with extratemporal epilepsy. The presence of TIRDA strongly suggests TLE but may infrequently occur in extratemporal epilepsy. Caution should be used when using lateralized TLDA as a presurgical localizing finding.     

Abnormalities of auditory evoked magnetic fields and structural changes in the left hemisphere of male schizophrenics--a magnetoencephalographic-magnetic resonance imaging study

Functional and structural changes in 10 DSM-III-R male schizophrenics and 10 healthy volunteers were investigated using magnetoencephalographically (MEG) detected long-latency (N100 m) auditory evoked fields (AEFs) and magnetic resonance imaging (MRI). The AEFs were characterized by single moving equivalent dipoles, which were superimposed on MRIs. There were significant differences in dipole orientations and in AEF latencies in the left hemisphere of schizophrenics, when compared to the controls. The MEG-detected alterations were found to be associated with a bilateral volume reduction of the posterior superior temporal gyrus (pSTG), which was more pronounced in the left hemisphere. Separate analysis of white and gray matter has shown that the pSTG volume reduction resulted from decreased gray matter volumes without white matter changes. Both the functional and the morphological data indicate a left-hemispheric disturbance in our patients.     

Endothelin: role in hypertension

Thirty-nine elderly depressed patients as well as 15 demented patients with Alzheimer's disease and 11 healthy volunteers were imaged at rest with a high resolution single-slice 12-detector head scanner (SME-Neuro 900) and the cerebral perfusion marker 99mTc-Exametazime (HM-PAO). Statistical parametric maps were computed to compare early- and late-onset depressed, Alzheimer patients and healthy volunteers and to examine associations between regional perfusion and clinical and MRI variables. Patients with late-onset depression showed reductions in temporal lobe perfusion compared with early-onset depression and controls. Alzheimer patients had the expected reduced perfusion in temporoparietal and prefontal cortex, as well as basal ganglia, compared with healthy controls. Compared with depressed patients, they showed a relative reduction in temporoparietal cortex, only. This difference was more pronounced between Alzheimer patients and early onset, compared to late-onset patients with depression. Periventricular white matter changes on MRI were associated with temporal lobe reductions of tracer uptake in depression. In the Alzheimer group, deep white matter MRI changes were associated with frontal perfusion deficits. Our results support a vulnerability hypothesis, which predicts that patients with late-onset depression will show more brain changes than patients with an early onset of their illness. Statistical parametric mapping in patients with organic psychiatric brain syndromes is feasible and promising as a clinical and research method.     

Incidence of lesions described by magnetic resonance imaging in the clarification of focal epilepsy of frontal and temporal origin

AIM: Today, MRI is an integral part of the presurgical evaluation of patients suffering from partial epilepsy. These patients frequently show focal morphological abnormalities with potential epileptogenic character and surgical resection of these lesions is associated with superior postsurgical outcome as to seizure frequency. Apart from easily detectable defects, such as post-traumatic lesions or cerebral infarction, as wide variety of mainly small abnormalities can be detected using MRI. METHODS: In this study, 484 patients suffering from partial epilepsy of temporal or frontal onset were evaluated for the incidence of different lesions in this population. RESULTS: All lesions found were included without evaluating their potential epileptogenicity, which remains to be proven using other procedures (EEG, SPECT, PET, etc.). Involvement of the hippocampal formation was a major finding in temporal lobe epilepsy, which could be detected as sclerosis (T2w-images), atrophy (T2w-TSE or T1w-IR-images) or both (15%). In addition and in declining frequency various tumors (14%), post-traumatic lesion (-5%), and focal cortical dysplasia or other disturbances of cortical integrity (-4%) were found. These lesions are detectable with best contrast on different sequences. As a consequence it is suggested to acquire sequences in 3 dimensions including a T1w-SE, two (coronal and axial) double-echo-SE sequences and similarly two T1w-IR-sequences. The application of contrast media can be restricted to special questions, derived either from the first imaging results or from the patients history. CONCLUSION: Using qualitative data for interpretation, the sensitivity as to the detection of any focal pathology of a recent-generation MRI in this population was 75%, with 79% for temporal lobe epilepsies and 67% for frontal lobe epilepsies. Quantitative measurements of hippocampal volume or signal seem to be able to increase the sensitivity of the method.