Beta-propeller protein-associated neurodegeneration presenting Rett-like features: A case report and literature review.

Several patients with beta-propeller protein-associated neurodegeneration (BPAN)/static encephalopathy with neurodegeneration in adulthood have been reported to present Rett syndrome (RTT)-like features. This report presents an individual with BPAN showing clinical features of RTT. Psychomotor delay and epilepsy onset were noted at 1 year, and regression began at 4 years. Screening of the methyl-CpG binding protein 2 (MECP2) did not show variants. At 22 years, basal ganglia iron deposits were found on magnetic resonance imaging (MRI), and the WD-domain repeat 45 gene (WDR45) variant was identified. Review of the literature showed that BPAN with RTT-like features is associated with more epileptic seizures and less deceleration of head growth, breathing irregularities, and cold extremities than classic RTT with MECP2 variants. These clinical presentations may provide clues for differentiating between these two disorders. However, both WDR45 and MECP2 should be screened in patients presenting a clinical picture of RTT without specific MRI findings of BPAN.

Crisis parciales complejas y lesión estructural cerebelosa / Complex partial seizures and cerebellar structural damage

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Jazz, guitar, and neurosurgery: the Pat Martino case report.

OBJECTIVE: We present the case of a professional jazz guitarist with temporal lobe epilepsy secondary to an arteriovenous cerebral malformation. CASE DESCRIPTION: The patient underwent a left temporal lobectomy in 1980. After surgery, he presented with severe retrograde amnesia and complete loss of musical interest and capabilities. The patient's musical abilities recovered over time, and he regained his previous virtuoso status. In 2007, his medical history, neuropsychologic functions, and structural magnetic resonance imaging study were examined and revealed a remarkable degree of recovery of memory and musical abilities in the context of extensive temporal lobe resection. The neuropsychologic findings and neuroanatomic features of the magnetic resonance imaging study were analyzed to try to understand the high degree of recovery of both long-term memory and musical processing abilities in this musician. CONCLUSIONS: This case reveals the possibility of an unusual degree of cerebral plasticity and reorganization. Additionally, it emphasizes the question of musical virtuosity. This report shows that the musical capabilities of professional musicians, in specific cases, can completely recover even when much of the left temporal lobe has been removed.

Neurobehavioral comorbidities of pediatric epilepsies are linked to thalamic structural abnormalities.

PURPOSE: Neurobehavioral comorbidities are common in pediatric epilepsy with enduring adverse effects on functioning, but their neuroanatomic underpinning is unclear. Striatal and thalamic abnormalities have been associated with childhood-onset epilepsies, suggesting that epilepsy-related changes in the subcortical circuit might be associated with the comorbidities of children with epilepsy. We aimed to compare subcortical volumes and their relationship with age in children with complex partial seizures (CPS), childhood absence epilepsy (CAE), and healthy controls (HC). We examined the shared versus unique structural-functional relationships of these volumes with behavior problems, intelligence, language, peer interaction, and epilepsy variables in these two epilepsy syndromes. METHODS: We investigated volumetric differences of caudate, putamen, pallidum, and thalamus in children with CPS (N = 21), CAE (N = 20), and HC (N = 27). Study subjects underwent structural magnetic resonance imaging (MRI), intelligence, and language testing. Parent-completed Child Behavior Checklists provided behavior problem and peer interaction scores. We examined the association of age, intelligence quotient (IQ), language, behavioral problems, and epilepsy variables with subcortical volumes that were significantly different between the children with epilepsy and HC. KEY FINDINGS: Both children with CPS and CAE exhibited significantly smaller left thalamic volume compared to HC. In terms of developmental trajectory, greater thalamic volume was significantly correlated with increasing age in children with CPS and CAE but not in HC. With regard to the comorbidities, reduced left thalamic volumes were related to more social problems in children with CPS and CAE. Smaller left thalamic volumes in children with CPS were also associated with poor attention, lower IQ and language scores, and impaired peer interaction. SIGNIFICANCE: Our study is the first to directly compare and detect shared thalamic structural abnormalities in children with CPS and CAE. These findings highlight the vulnerability of the thalamus and provide important new insights on its possible role in the neurobehavioral comorbidities of childhood-onset epilepsy.

Lack of association between polymorphism in ABCC2 gene and response to antiepileptic drug treatment in Croatian patients with epilepsy.

Despite advances in antiepileptic drug (AED) therapy, about one-third of patients with epilepsy are resistant to drug treatment. Functional impact of polymorphisms in drug-efflux transporter genes may contribute to multidrug resistance theory. Studies on ABCB1 gene gave contradictory results and available data suggest that this polymorphism may not directly cause altered P-glycoprotein (Pgp) transport activity but may be associated with one or more causal variants in the stretch of linkage disequilibrium or is caused by multiple gene polymorphisms. Genetic polymorphisms also occur frequently in other transmembrane transport systems including the multidrug resistance proteins (MRPs, ABCC2). The aim of this research was to investigate the possible association of ABCC2 gene polymorphisms G1249A in exon 10 and C24T in exon 1 with the development of drug resistance. This cross-sectional study is a part of ongoing pharmacogenomic study of epilepsy in Croatian population. All patients enrolled in the study had an established diagnosis of partial complex epilepsy with or without secondary generalization with non lesional brain MRI with epilepsy protocol and have been suffering for more than two years. They were divided into two groups. The first group comprised 52 patients refractory to the current therapy, while the second group consisted of 45 patients with well-controlled seizures. Our data did not identify any significant association between genetic polymorphisms of exon 1 (24C > T) and exon 10 (1249G < A) of ABCC2 gene or any combined effect in response to AED treatment and development of drug resistance in patients with partial complex epilepsy. Statistical significant difference was not found in genotype based analysis, allele frequency, haplotype and combined genotype analysis.

A minimum of 3 months of dietary fish oil supplementation is required to raise amygdaloid afterdischarge seizure thresholds in rats--implications for treating complex partial seizures.

Complex partial seizures, which typically originate in limbic structures such as the amygdala, are often resistant to antiseizure medications. Our goal was to investigate the effects of chronic dietary supplementation with n-3 polyunsaturated fatty acids (PUFAs) derived from fish oil on seizure thresholds in the amygdala, as well as on blood and brain PUFA levels. The acute effects of injected n-3 PUFAs--eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)--were also tested in the maximal pentylenetetrazol (PTZ) seizure model. In amygdala-implanted subjects, fish oil supplementation significantly increased amygdaloid afterdischarge thresholds, as compared with controls at 3, 5, and 7 months after the start of supplementation. Fish oil supplementation also increased serum EPA and DHA concentrations. DHA concentration in the pyriform-amygdala area increased in the fish-oil treated group by 17-34%, but this effect did not reach statistical significance (P=0.065). DHA significantly increased the latency to seizure onset in the PTZ seizure model, whereas EPA had no significant effect. These observations suggest that chronic dietary fish oil supplementation can raise focal amygdaloid seizure thresholds and that this effect is likely mediated by DHA rather than by EPA.

Transmantle sign in focal cortical dysplasia: a unique radiological entity with excellent prognosis for seizure control.

OBJECT: Focal cortical dysplasia (FCD) represents a spectrum of developmental cortical abnormalities and is one of the most common causes of intractable epilepsy in children and young adults. Outcomes after surgery for FCD are highly variable, and prognosticators of seizure freedom are unclear. In a subset of FCDs, a transmantle sign is observed on imaging that focally spans the entire cerebral mantle from the ventricle to the cortical surface. The aim of this study was to characterize seizure control outcomes and prognostic significance of the transmantle sign in FCD epilepsy. METHODS: Fourteen patients with the transmantle sign underwent epilepsy surgery for medically refractory epilepsy. Thirteen patients underwent resective surgery and 1 underwent multiple subpial transections with vagus nerve stimulator placement. Patient demographics, MRI, electroencephalography, intraoperative electrocorticography (ECoG), and pathology were reviewed. The results of this series were compared with those of 114 previously reported patients with FCD without the transmantle sign. RESULTS: All patients were found to have childhood seizure onset and concordant MRI and ECoG findings. The primary MRI findings associated with transmantle sign included gray-white junction blurring, appearance of cortical thickening, T2 or FLAIR abnormality, and bottom-of-the-sulcus dysplasia. The transmantle sign was usually a focal finding, typically confined to 1 or several gyri with well-circumscribed epileptic tissue. Correlation of the transmantle sign with FCD histopathological subtypes was highly variable. Patients who underwent complete resection of MRI and ECoG abnormalities (12 of 13 patients) became seizure free. When compared with 114 FCD patients without the transmantle sign, patients with the transmantle sign showed significantly improved seizure-free outcomes after complete resections (p = 0.04). CONCLUSIONS: The presence of the transmantle sign in patients with medically refractory partial epilepsy is associated with highly favorable seizure control outcomes after surgical treatment.

Slow cortical dynamics and the accumulation of information over long timescales.

Making sense of the world requires us to process information over multiple timescales. We sought to identify brain regions that accumulate information over short and long timescales and to characterize the distinguishing features of their dynamics. We recorded electrocorticographic (ECoG) signals from individuals watching intact and scrambled movies. Within sensory regions, fluctuations of high-frequency (64-200 Hz) power reliably tracked instantaneous low-level properties of the intact and scrambled movies. Within higher order regions, the power fluctuations were more reliable for the intact movie than the scrambled movie, indicating that these regions accumulate information over relatively long time periods (several seconds or longer). Slow (<0.1 Hz) fluctuations of high-frequency power with time courses locked to the movies were observed throughout the cortex. Slow fluctuations were relatively larger in regions that accumulated information over longer time periods, suggesting a connection between slow neuronal population dynamics and temporally extended information processing.

Periventricular nodular heterotopia functionally couples with the overlying hippocampus.

Patients with periventricular nodular heterotopia (PVNH) often have severe epilepsy. However, it is unclear how the heterotopia contributes to epileptogenesis. Recently, electrophysiologic studies using intraoperative depth electrodes have indicated that interaction between the heterotopia and overlying cortex is crucial for seizure onset. We performed an in vitro physiologic study using slices of resected brain from a 22-year-old man with PVNH, who manifested medically refractory mesial temporal lobe epilepsy. Preoperative evaluation indicated that the right mesial temporal structure and PVNH were the epileptogenic focus. The resected tissue was immediately immersed in cold artificial cerebrospinal fluid, and then slices of the brain tissue including the heterotopic nodules and overlying hippocampus were prepared. We electrically stimulated the incubated slices, and the elicited neural activities were analyzed as changes in the flavoprotein fluorescence signals. When we stimulated either the heterotopic nodule or the overlying hippocampus, clear functional coupling of neural activities between these structures was observed. The coupling response evoked by stimulation of the subiculum and developing within the heterotopic nodule was enhanced by application of bicuculline. Therefore, activities of the hippocampus and the nodule are closely correlated.

Temporal resolution deficits in patients with refractory complex partial seizures and mesial temporal sclerosis (MTS).

We studied the temporal resolution ability in patients with refractory complex partial seizures and mesial temporal sclerosis (MTS) using Gaps-In-Noise (GIN) test in a prospective cross-sectional study. Thirteen patients with right MTS (age: 31±7.67 years; M:F=8:5) and 13 patients with left MTS (age: 25.76±8.26 years; M:F=9:4) having normal hearing and mini-mental state examination (MMSE) score of >23/30 were recruited. Fifty healthy volunteers (26.3±5.17 years; M:F=28:22) formed the control group. Gaps-In-Noise test demonstrated impaired temporal resolution: 69.2% of patients with right MTS (RMTS) and 76.9% of patients with left MTS (LMTS) had abnormal scores in the right ear for gap detection threshold (GDT) measure. Similarly, 53.8% of patients in the RMTS group and 76.9% of patients in the LMTS group had abnormal scores in the left ear. In percentage of correct identification (PCI), 46.1% of patients with RMTS and 69.2% of patients with LMTS had poorer scores in the right ear, whereas 46.1% of patients with RMTS and 61.5% of patients with LMTS had poorer scores in the left ear. Both patient groups, viz., RMTS and LMTS, demonstrated bilateral temporal resolution deficits.

Levetiracetam y Psicosis / No disponible

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Validation of connectivity-based thalamic segmentation with direct electrophysiologic recordings from human sensory thalamus.

Connectivity-based segmentation has been used to identify functional gray matter subregions that are not discernable on conventional magnetic resonance imaging. However, the accuracy and reliability of this technique has only been validated using indirect means. In order to provide direct electrophysiologic validation of connectivity-based thalamic segmentations within human subjects, we assess the correlation of atlas-based thalamic anatomy, connectivity-based thalamic maps, and somatosensory evoked thalamic potentials in two adults with medication-refractory epilepsy who were undergoing intracranial EEG monitoring with intrathalamic depth and subdural cortical strip electrodes. MRI with atlas-derived localization was used to delineate the anatomic boundaries of the ventral posterolateral (VPL) nucleus of the thalamus. Somatosensory evoked potentials with intrathalamic electrodes physiologically identified a discrete region of phase reversal in the ventrolateral thalamus. Finally, DTI was obtained so that probabilistic tractography and connectivity-based segmentation could be performed to correlate the region of thalamus linked to sensory areas of the cortex, namely the postcentral gyrus. We independently utilized these three different methods in a blinded fashion to localize the "sensory" thalamus, demonstrating a high-degree of reproducible correlation between electrophysiologic and connectivity-based maps of the thalamus. This study provides direct electrophysiologic validation of probabilistic tractography-based thalamic segmentation. Importantly, this study provides an electrophysiological basis for using connectivity-based segmentation to further study subcortical anatomy and physiology while also providing the clinical basis for targeting deep brain nuclei with therapeutic stimulation. Finally, these direct recordings from human thalamus confirm early inferences of a sensory thalamic component of the N18 waveform in somatosensory evoked potentials.

Emergence of complex partial epilepsy-like experiences following closed head injuries: personality variables and neuropsychological profiles.

To pursue Richard Roberts' epileptic spectrum disorder (ESD) and the emergence of complex partial epilepsy-like experiences, items and total scores for the ESD Inventory were examined for 185 patients who had sustained mechanical impacts (and were diagnosed with or without neuropsychological impairment) and a reference group (n=68) of university students. Results from neuropsychological, personality, neurological screening, and interview data supported the role of temporal lobe origins for these experiences. The incidences of these experiences were sufficient to adversely affect adaptation and to produce psychiatric profiles. Although only 70% of the patients who were impaired versus not impaired could be differentiated by items from the ESD Inventory, >95% of the patients with scores >100 on the ESD Inventory displayed abnormal scores on more than four Minnesota Multiphasic Personality Inventory scales. These results support Roberts' ESD concept and strongly suggest that persistent, subclinical occurrence of these experiences could be the cause or major correlate of neuropsychological impairment for these patients.

Partial rhombencephalosynapsis and Chiari type II malformation in a child: a true association supported by DTI tractography.

Partial rhombencephalosynapsis (PRECS) has been recently reported in association with Chiari II (CII). However, its existence as a true malformation is challenged due to the anatomical changes potentially induced by CII. The aim of this report was to investigate the contribution of midbrain/hindbrain tractography in this setting. A 13-year-old boy with a known CII malformation and operated myelomeningocele was referred for brain imaging after a first complex partial seizure. In addition to the classical features of CII, MRI showed partially fused cerebellar hemispheres and multiple supratentorial abnormalities. Diffusion tensor imaging (DTI) color map and tractography showed absent transverse fibers on the midsection of the cerebellum, scarce fibers of the middle cerebellar peduncle (MCP), absence of the middle pontine crossing tract, and fibers running vertically in the medial part of the cerebellum. Vertical mediocerebellar fibers are a feature of classical RECS and the paucity or absence of MCP fibers is mainly described in CII. In our patient, DTI and FT therefore demonstrated structural characteristics of both RECS and CII confirming their potential coexistence and suggesting possible shared embryological pathway.

Intraparenchymal schwannomas: report of two new cases studied with MRI and review of the literature.

Intraparenchymal schwannomas are very rare tumours. We present two young adult patients operated for this type of lesion who show no signs of recurrence 2 years after surgery. These tumours have a bimodal peak of presentation: most occur in young patients under 25 years, and the rest present in the elderly. Characteristically they show both Antoni A and Antoni B areas, intense inmunoreactivity to S-100 and Vimentin protein, and none to EMA or CD34. Electron microscopy is diagnostic when basal membrane is found around the cytoplasmatic processes. MRI spectroscopy depicts increased myoinositol, choline and lipids, and perfusion MR demonstrates high rCBV with a characteristic curve due to the total absence of blood brain barrier. An origin in the Schwann cells of the perivascular nervous plexus in the subarachnoid space is the most accepted theory for the histogenesis of these tumours. We propose to perform the characterization of a series of markers such as SOX-10 in every new case in order to prove that theory.

Emergence of persistent networks in long-term intracranial EEG recordings.

Over the past two decades, the increased ability to analyze network relationships among neural structures has provided novel insights into brain function. Most network approaches, however, focus on static representations of the brain's physical or statistical connectivity. Few studies have examined how brain functional networks evolve spontaneously over long epochs of continuous time. To address this, we examine functional connectivity networks deduced from continuous long-term electrocorticogram recordings. For a population of six human patients, we identify a persistent pattern of connections that form a frequency-band-dependent network template, and a set of core connections that appear frequently and together. These structures are robust, emerging from brief time intervals (~100 s) regardless of cognitive state. These results suggest that a metastable, frequency-band-dependent scaffold of brain connectivity exists from which transient activity emerges and recedes.

Anti-NMDA receptor encephalitis associated with ictal asystole.

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis usually presents with psychiatric symptoms, behavioural changes, impaired consciousness, seizures and autonomic instability. Ictal asystole is a rare phenomenon associated with complex partial seizures. It is implicated as a potential cause of sudden unexpected death in epilepsy. We report a 41-year-old woman who presented with anti-NMDAR encephalitis. During continuous video electroencephalogram and cardiac monitoring, an episode of ictal asystole was detected. We discuss the potential link between anti-NMDAR encephalitis and ictal asystole. Treatment options for ictal asystole in the setting of anti-NMDAR encephalitis are also discussed.