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1.
Neurocrit Care ; 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38918336

RESUMEN

BACKGROUND: Depth electroencephalography (dEEG) is a recent invasive monitoring technique used in patients with acute brain injury. This study aimed to describe in detail the clinical manifestations of nonconvulsive seizures (NCSzs) with and without a surface EEG correlate, analyze their long-standing effects, and provide data that contribute to understanding the significance of certain scalp EEG patterns observed in critically ill patients. METHODS: We prospectively enrolled a cohort of 33 adults with severe acute brain injury admitted to the neurological intensive care unit. All of them underwent multimodal invasive monitoring, including dEEG. All patients were scanned on a 3T magnetic resonance imaging scanner at 6 months after hospital discharge, and mesial temporal atrophy (MTA) was calculated using a visual scale. RESULTS: In 21 (65.6%) of 32 study participants, highly epileptiform intracortical patterns were observed. A total of 11 (34.3%) patients had electrographic or electroclinical seizures in the dEEG, of whom 8 had both spontaneous and stimulus-induced (SI) seizures, and 3 patients had only spontaneous intracortical seizures. An unequivocal ictal scalp correlate was observed in only 3 (27.2%) of the 11 study participants. SI-NCSzs occurred during nursing care, medical procedures, and family visits. Subtle clinical manifestations, such as restlessness, purposeless stereotyped movements of the upper limbs, ventilation disturbances, jerks, head movements, hyperextension posturing, chewing, and oroalimentary automatisms, occurred during intracortical electroclinical seizures. MTA was detected in 18 (81.8%) of the 22 patients. There were no statistically significant differences between patients with MTA with and without seizures or status epilepticus. CONCLUSIONS: Most NCSzs in critically ill comatose patients remain undetectable on scalp EEG. SI-NCSzs frequently occur during nursing care, medical procedures, and family visits. Semiology of NCSzs included ictal minor signs and subtle symptoms, such as breathing pattern changes manifested as patient-ventilator dyssynchrony.

2.
Neurosurg Focus ; 48(2): E7, 2020 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-32006945

RESUMEN

OBJECTIVE: The functional importance of the superior temporal lobe at the level of Heschl's gyrus is well known. However, the organization and function of these cortical areas and the underlying fiber tracts connecting them remain unclear. The goal of this study was to analyze the area formed by the organization of the intersection of Heschl's gyrus-related fiber tracts, which the authors have termed the "Heschl's gyrus fiber intersection area" (HGFIA). METHODS: The subcortical connectivity of Heschl's gyrus tracts was analyzed by white matter fiber dissection and by diffusion tensor imaging tractography. The white matter tracts organized in relation to Heschl's gyrus were isolated in 8 human hemispheres from cadaveric specimens and in 8 MRI studies in 4 healthy volunteers. In addition, these tracts and their functions were described in the surgical cases of left temporal gliomas next to the HGFIA in 6 patients who were awake during surgery and underwent intraoperative electrical stimulation mapping. RESULTS: Five tracts were observed to pass through the HGFIA: the anterior segment of the arcuate fasciculus, the middle longitudinal fasciculus, the acoustic radiation, the inferior fronto-occipital fasciculus, and the optic radiation. In addition, U fibers originating at the level of Heschl's gyrus and heading toward the middle temporal gyrus were identified. CONCLUSIONS: This investigation of the HGFIA, a region where 5 fiber tracts intersect in a relationship with the primary auditory area, provides new insights into the subcortical organization of Wernicke's area. This information is valuable when a temporal surgical approach is planned, in order to assess the surgical risk related to language disturbances.


Asunto(s)
Corteza Auditiva/diagnóstico por imagen , Corteza Auditiva/fisiología , Vías Auditivas/diagnóstico por imagen , Vías Auditivas/fisiología , Percepción Auditiva/fisiología , Lenguaje , Adulto , Anciano , Anciano de 80 o más Años , Corteza Auditiva/anatomía & histología , Vías Auditivas/anatomía & histología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fibras Nerviosas/fisiología , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/fisiología
3.
Epilepsy Behav ; 49: 184-8, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25986321

RESUMEN

BACKGROUND: Fat embolism syndrome (FES) is a rare complication of long-bone fractures and joint reconstruction surgery. To the best of our knowledge, we describe the clinical, electrophysiological, neuroimaging, and neuropathological features of the first case of super-refractory nonconvulsive status epilepticus (sr-NCSE) secondary to fat embolism. CLINICAL CASE: An 82-year-old woman was transferred to our intensive care unit because of a sudden decrease of consciousness level, right hemiparesis, and acute respiratory failure in the early postoperative period of knee prosthesis surgery. Brain computed tomography (TC) including angio-CT and CT perfusion was normal. An urgent video-electroencephalography (v-EEG) evaluation showed continuous sharp-and slow-wave at 2.0-2.5 Hz in keeping with the diagnosis of generalized NCSE. Epileptiform discharges ceased after the administration of 5mg of intravenous diazepam, and background activity constituted by diffuse theta waves was observed without clinical improvement. Treatment with levetiracetam (1000 mg/day) and sedation with propofol and midazolam were initiated. Moreover, continuous v-EEG monitoring was also started. Despite antiepileptic therapy, epileptiform activity recurred after the interruption of profound sedation, and valproate and lacosamide were added during the ensuing days. Magnetic resonance imaging (MRI) disclosed small scattered foci of acute ischemic infarcts and diffuse petechiae involving the basal ganglia and pons and centrum semiovale in keeping with fat embolism. Super-refractory nonconvulsive status epilepticus remained without control for 2 weeks. Finally, the patient died. The clinical autopsy revealed a bilateral lung fat embolism associated with a hemorrhagic infarction in the left lower lobe. Fatty lesions were also seen in the intestine and pancreas. Scattered microscopic cerebral infarcts associated with fat emboli in the capillaries were noticed, affecting both supra- and infratentorial structures. In addition, occasional focal areas of ischemic injury showing filiform neurons with reactive astrocytic gliosis background consistent with acute lesions were observed in CA3. CONCLUSIONS: Fat embolism should be considered a potential cause of sr-NCSE. This article is part of a Special Issue entitled "Status Epilepticus".


Asunto(s)
Embolia Grasa/complicaciones , Procedimientos Ortopédicos/efectos adversos , Estado Epiléptico/diagnóstico , Estado Epiléptico/etiología , Anciano de 80 o más Años , Anticonvulsivantes/uso terapéutico , Electroencefalografía , Embolia Grasa/etiología , Resultado Fatal , Femenino , Humanos , Imagen por Resonancia Magnética , Estado Epiléptico/tratamiento farmacológico
4.
Clin Anat ; 27(4): 563-9, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24453050

RESUMEN

Precise knowledge of the connectivities of the different white matter bundles is of great value for neuroscience research. Our knowledge of subcortical anatomy has improved exponentially during recent decades owing to the development of magnetic resonance diffusion tensor imaging tractography (DTI). Although DTI tractography has led to important progress in understanding white matter anatomy, the precise trajectory and cortical connections of the subcortical bundles remain poorly determined. The recent literature was extensively reviewed in order to analyze the trajectories and cortical terminations of the lateral association fibers of the brain.The anatomy of the following tracts is reviewed: superior longitudinal fasciculus, middle longitudinal fasciculus, inferior longitudinal fasciculus, inferior fronto-occipital fasciculus, uncinate fasciculus, frontal aslant tract, and vertical occipital fasciculus. The functional role of a tract can be inferred from its topography within the brain. Knowing the functional roles of the cortical areas connected by a certain bundle, it is possible to develop new insights into the putative functional properties of such connections.


Asunto(s)
Encéfalo/anatomía & histología , Fibras Nerviosas Mielínicas , Humanos
5.
medRxiv ; 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38405699

RESUMEN

Background: GAA-FGF14 ataxia (SCA27B) is a recently reported late-onset ataxia caused by a GAA repeat expansion in intron 1 of the FGF14 gene. Initial studies revealed cerebellar atrophy in 74-97% of patients. A more detailed brain imaging characterization of GAA-FGF14 ataxia is now needed to provide supportive diagnostic features and earlier disease recognition. Methods: We performed a retrospective review of the brain MRIs of 35 patients (median age at MRI 63 years; range 28-88 years) from Quebec (n=27), Nancy (n=3), Perth (n=3) and Bengaluru (n=2) to assess the presence of atrophy in vermis, cerebellar hemispheres, brainstem, cerebral hemispheres, and corpus callosum, as well as white matter involvement. Following the identification of the superior cerebellar peduncles (SCPs) involvement, we verified its presence in 54 GAA-FGF14 ataxia patients from four independent cohorts (Tübingen n=29; Donostia n=12; Innsbruck n=7; Cantabria n=6). To assess lobular atrophy, we performed quantitative cerebellar segmentation in 5 affected subjects with available 3D T1-weighted images and matched controls. Results: Cerebellar atrophy was documented in 33 subjects (94.3%). We observed SCP involvement in 22 subjects (62.8%) and confirmed this finding in 30/54 (55.6%) subjects from the validation cohorts. Cerebellar segmentation showed reduced mean volumes of lobules X and IV in the 5 affected individuals. Conclusions: Cerebellar atrophy is a key feature of GAA-FGF14 ataxia. The frequent SCP involvement observed in different cohorts may facilitate the diagnosis. The predominant involvement of lobule X correlates with the frequently observed downbeat nystagmus.

6.
J Anat ; 219(4): 531-41, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21767263

RESUMEN

Classical fiber dissection of post mortem human brains enables us to isolate a fiber tract by removing the cortex and overlying white matter. In the current work, a modification of the dissection methodology is presented that preserves the cortex and the relationships within the brain during all stages of dissection, i.e. 'cortex-sparing fiber dissection'. Thirty post mortem human hemispheres (15 right side and 15 left side) were dissected using cortex-sparing fiber dissection. Magnetic resonance imaging study of a healthy brain was analyzed using diffusion tensor imaging (DTI)-based tractography software. DTI fiber tract reconstructions were compared with cortex-sparing fiber dissection results. The fibers of the superior longitudinal fasciculus (SLF), inferior fronto-occipital fasciculus (IFOF), inferior longitudinal fasciculus (ILF) and uncinate fasciculus (UF) were isolated so as to enable identification of their cortical terminations. Two segments of the SLF were identified: first, an indirect and superficial component composed of a horizontal and vertical segment; and second, a direct and deep component or arcuate fasciculus. The IFOF runs within the insula, temporal stem and sagittal stratum, and connects the frontal operculum with the occipital, parietal and temporo-basal cortex. The UF crosses the limen insulae and connects the orbito-frontal gyri with the anterior temporal lobe. Finally, a portion of the ILF was isolated connecting the fusiform gyrus with the occipital gyri. These results indicate that cortex-sparing fiber dissection facilitates study of the 3D anatomy of human brain tracts, enabling the tracing of fibers to their terminations in the cortex. Consequently, it is an important tool for neurosurgical training and neuroanatomical research.


Asunto(s)
Encéfalo/anatomía & histología , Disección/métodos , Fibras Nerviosas , Vías Nerviosas/anatomía & histología , Anciano , Anciano de 80 o más Años , Humanos
8.
AJR Am J Roentgenol ; 196(3): W316-25, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21343482

RESUMEN

OBJECTIVE: The objective of this article is to present a comprehensive review of apophysitis of the lower limb regarding anatomy, physiopathology, clinical findings, differential diagnosis, and imaging features with special emphasis on MRI. CONCLUSION: Apophysitis, which is inflammation of the traction epiphysis resulting from chronic trauma, is a common abnormality that affects the growing child. Understanding the physiopathology of apophysitis is essential for a precise diagnosis on MRI. Accurate identification of key MRI features of this entity may prevent misdiagnosis and inappropriate management of apophysitis.


Asunto(s)
Traumatismos en Atletas/diagnóstico , Epífisis/lesiones , Traumatismos de la Pierna/diagnóstico , Imagen por Resonancia Magnética/métodos , Osteocondritis/diagnóstico , Traumatismos en Atletas/fisiopatología , Diagnóstico Diferencial , Humanos , Traumatismos de la Pierna/fisiopatología , Osteocondritis/fisiopatología
9.
Neuroimage ; 49(1): 199-204, 2010 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-19619664

RESUMEN

OBJECTIVE: Disruptions in white matter structure have consistently been shown in schizophrenia--but mainly in patients in whom the illness is well-established. In order to determine whether white matter abnormalities are present at illness onset, and to minimise the potentially confounding effects of chronic illness and treatment, we used diffusion tensor imaging to study a large cohort of first episode psychotic patients who were medication-naive. METHODS: Sixty two first episode patients and 54 controls matched on age, sex, years of education and laterality index underwent diffusion tensor imaging. Data were acquired on a GE Signa NVi 1.5 Tesla System. Fractional anisotropy maps were generated on a voxel-by-voxel basis. An optimized voxel-based morphometry technique was conducted with two-stage registration approach. Group differences were examined using a non-parametric statistical method. RESULTS: The voxelwise analysis revealed four clusters where fractional anisotropy values were significantly lower in patients than controls. These were localised bilaterally to regions of white matter corresponding to superior and inferior longitudinal fasciculus, forceps major, anterior and superior thalamic radiation and corpus callosum. CONCLUSIONS: Reductions in white matter integrity are present early in the course of the schizophrenia and localised in fascicule that connect brain regions implicated in the disorder.


Asunto(s)
Encéfalo/patología , Trastornos Psicóticos/patología , Adolescente , Adulto , Anisotropía , Antipsicóticos/uso terapéutico , Enfermedad Crónica , Diagnóstico Dual (Psiquiatría) , Imagen de Difusión por Resonancia Magnética , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Esquizofrenia/patología , Trastornos Relacionados con Sustancias/patología , Adulto Joven
10.
Prog Neuropsychopharmacol Biol Psychiatry ; 32(8): 1936-43, 2008 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-18930104

RESUMEN

BACKGROUND: The effect of antipsychotic drugs on brain morphology is under debate. Here we investigate the effects of risperidone, olanzapine and low doses of haloperidol on cortical and subcortical morphometry in first episode drug naïve patients with non-affective psychosis. METHODS: Morphological variables were measured in three treatment groups (haloperidol=18; risperidone=16; olanzapine=18) and in healthy subjects (N=38) at baseline and after one year. The relationship between brain morphometric changes and changes in clinical scores was also assessed. RESULTS: At one year, the three antipsychotics had had an equal effect on the gray matter cortical structure, overall and lobes (all p's>0.121.). A significant time-by-group interaction was found in lateral ventricle volume (F2,47=5.65; p=0.006). Post-hoc comparisons revealed a significant increase in lateral ventricles in patients treated with risperidone (p=0.009). Patients exposed to atypicals (olanzapine and risperidone) exhibited a decrease in caudate nucleus volume (p=0.001). In general, brain changes did not account in any significant manner for clinical changes over time in any treatment group. CONCLUSIONS: We conclude that low doses of haloperidol, risperidone and olanzapine seem to have an equal effect on the gray matter cortical structure after 1 year of treatment. In contrast to typical antipsychotics, atypicals have differential effects on lateral ventricle and caudate nucleus volumes.


Asunto(s)
Antipsicóticos/farmacología , Encéfalo/efectos de los fármacos , Trastornos Mentales/patología , Adulto , Análisis de Varianza , Antipsicóticos/uso terapéutico , Benzodiazepinas/farmacología , Benzodiazepinas/uso terapéutico , Encéfalo/patología , Método Doble Ciego , Femenino , Estudios de Seguimiento , Haloperidol/farmacología , Haloperidol/uso terapéutico , Humanos , Imagen por Resonancia Magnética , Masculino , Trastornos Mentales/tratamiento farmacológico , Olanzapina , Escalas de Valoración Psiquiátrica , Risperidona/farmacología , Risperidona/uso terapéutico , Adulto Joven
11.
Radiographics ; 28(6): 1673-87, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18936029

RESUMEN

Acute stroke services have been installed in most hospitals in the industrialized world, and dealing with hyperacute stroke has become one of the most frequently performed tasks of the on-call radiologist. Imaging plays a key role in current guidelines for thrombolysis, and knowledge of classic early ischemic signs or depiction of hemorrhage at nonenhanced computed tomography (CT) is necessary (although not sufficient) for a satisfactory imaging study. A modern CT examination must also include perfusion CT and CT angiography. Perfusion CT delineates the ischemic tissue (penumbra) by showing increased mean transit time with decreased cerebral blood flow (CBF) and normal or increased cerebral blood volume (CBV), whereas infarcted tissue manifests with markedly decreased CBF and decreased CBV. CT angiography can depict the occlusion site, help grade collateral blood flow, and help characterize carotid atherosclerotic disease. A complete CT study (nonenhanced CT, perfusion CT, and CT angiography) may be performed and analyzed rapidly and easily by general radiologists using a simple standardized protocol and may even facilitate diagnosis by less experienced radiologists in affected patients.


Asunto(s)
Angiografía Cerebral/métodos , Cuidados Críticos/métodos , Guías de Práctica Clínica como Asunto , Accidente Cerebrovascular/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Humanos , Estados Unidos
13.
Neurosurgery ; 83(6): 1209-1218, 2018 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-29351666

RESUMEN

BACKGROUND: Recent glioma surgery series with intraoperative electrical stimulation (IES) language mapping have demonstrated high rates of postoperative memory impairment, raising a question regarding the efficacy of this approach to preserve memory. OBJECTIVE: To evaluate if intraoperative identification and preservation of verbal memory sites with IES mapping in diffuse gliomas in eloquent areas consistently protect patients from long-term postoperative decline in short-term memory. METHODS: A cohort of 16 subjects with diffuse low-grade or anaplastic gliomas that were operated with IES and intraoperative evaluation of language and verbal memory (cohort A) was matched by tumor side, pathology, and radiotherapy with a cohort of 16 subjects that were operated with IES and evaluation of language (cohort B). Detailed neuropsychological assessment was performed before and 6 mo after surgery. RESULTS: Intraoperative memory mapping was a strong predictor of verbal memory prognosis. In cohort A, 4 patients (26.7%) had a decline of at least one of the 4 short-term memory tests evaluated. In cohort B, 11 patients (73.3%) had a decline of at least one of the 4 tests. This difference was statistically significant in multivariate analysis (P = .022; odds ratio = 9.88; 95% confidence interval = 1.39-70.42). CONCLUSION: Verbal memory areas identified intraoperatively with the current paradigm are critically involved in verbal memory, as memory impairment can be significantly reduced by adapting the resection to avoid those memory areas. Incorporation of verbal memory evaluation in stimulation mapping protocols might assist in reducing postoperative sequelae and preserving the patient's quality of life.


Asunto(s)
Neoplasias Encefálicas/cirugía , Glioma/cirugía , Monitorización Neurofisiológica Intraoperatoria/métodos , Trastornos de la Memoria/prevención & control , Procedimientos Neuroquirúrgicos/efectos adversos , Adulto , Mapeo Encefálico/métodos , Estudios de Cohortes , Estimulación Eléctrica/métodos , Femenino , Humanos , Masculino , Memoria/fisiología , Trastornos de la Memoria/etiología , Persona de Mediana Edad , Análisis Multivariante , Pronóstico
14.
Schizophr Res ; 91(1-3): 87-96, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17306506

RESUMEN

OBJECTIVE: Striatal dysfunction has been traditionally implicated in the pathophysiology of schizophrenia. The purpose of this study is to examine the relationship between caudate nucleus volumes and clinical and cognitive features of schizophrenic patients in an early phase of their illness. METHODS: Caudate nucleus volumes in previously untreated first episode patients with non-affective psychosis (N=76) and healthy comparison subjects (N=45) were measured. Caudate nucleus volume in the right and left hemispheres were automatically segmented and analyzed using BRAINS2. Analysis of covariance was used to control for intracranial volume. Severity of clinical symptoms was assessed using SAPS and SANS total scores. The relationship between cognitive dimensions, and caudate nucleus volume was evaluated. Finally, we examined the correlation between caudate volumes and the duration of untreated illness (DUI), duration of untreated psychosis (DUP) and duration of prodrome period (DPP). RESULTS: Right, left, and total caudate nucleus volumes did not differ significantly between patients and controls. Those patients with a longer DUP have smaller caudate nucleus. In addition, caudate nucleus volume was positively correlated with the severity of psychotic symptomatology. No significant associations were found between caudate nucleus volume and cognitive functioning. CONCLUSION: This group of first episode schizophrenia patients did not exhibit significant volumetric anomalies of the caudate nucleus. Despite this lack of volumetric abnormalities, a delay in receiving antipsychotic treatment and the severity of initial positive symptomatology were significantly associated with reduced caudate volume.


Asunto(s)
Núcleo Caudado/anatomía & histología , Núcleo Caudado/fisiopatología , Trastornos del Conocimiento/etiología , Esquizofrenia/complicaciones , Esquizofrenia/fisiopatología , Adolescente , Adulto , Ganglios Basales/fisiopatología , Trastornos del Conocimiento/diagnóstico , Trastornos del Conocimiento/fisiopatología , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Trastornos Psicóticos/diagnóstico , Trastornos Psicóticos/etiología , Psicología del Esquizofrénico , Índice de Severidad de la Enfermedad
15.
World Neurosurg ; 105: 1033.e1-1033.e5, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28602887

RESUMEN

BACKGROUND: Modern sign languages used by deaf people are fully expressive, natural human languages that are perceived visually and produced manually. The literature contains little data concerning human brain organization in conditions of deficient sensory information such as deafness. CASE DESCRIPTION: A deaf-mute patient underwent surgery of a left temporoinsular low-grade glioma. The patient underwent awake surgery with intraoperative electrical stimulation mapping, allowing direct study of the cortical and subcortical organization of sign language. We found a similar distribution of language sites to what has been reported in mapping studies of patients with oral language, including 1) speech perception areas inducing anomias and alexias close to the auditory cortex (at the posterior portion of the superior temporal gyrus and supramarginal gyrus); 2) speech production areas inducing speech arrest (anarthria) at the ventral premotor cortex, close to the lip motor area and away from the hand motor area; and 3) subcortical stimulation-induced semantic paraphasias at the inferior fronto-occipital fasciculus at the temporal isthmus. CONCLUSIONS: The intraoperative setup for sign language mapping with intraoperative electrical stimulation in deaf-mute patients is similar to the setup described in patients with oral language. To elucidate the type of language errors, a sign language interpreter in close interaction with the neuropsychologist is necessary. Sign language is perceived visually and produced manually; however, this case revealed a cross-modal recruitment of auditory and orofacial motor areas.


Asunto(s)
Mapeo Encefálico , Neoplasias Encefálicas/cirugía , Corteza Cerebral/patología , Sordera/patología , Glioma/cirugía , Lengua de Signos , Neoplasias Encefálicas/diagnóstico por imagen , Corteza Cerebral/diagnóstico por imagen , Sordera/diagnóstico por imagen , Sordera/fisiopatología , Electroencefalografía , Femenino , Glioma/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad , Vías Nerviosas/diagnóstico por imagen
16.
J Neurosurg ; 123(4): 1081-92, 2015 10.
Artículo en Inglés | MEDLINE | ID: mdl-25955870

RESUMEN

OBJECT: Little attention has been given to the functional challenges of the insular approach to the resection of gliomas, despite the potential damage of essential neural networks that underlie the insula. The object of this study is to analyze the subcortical anatomy of the insular region when infiltrated by gliomas, and compare it with the normal anatomy in nontumoral hemispheres. METHODS: Ten postmortem human hemispheres were dissected, with isolation of the inferior fronto-occipital fasciculus (IFOF) and the uncinate fasciculus. Probabilistic diffusion tensor imaging (DTI) tractography was used to analyze the subcortical anatomy of the insular region in 10 healthy volunteers and in 22 patients with insular Grade II and Grade III gliomas. The subcortical anatomy of the insular region in these 22 insular gliomas was compared with the normal anatomy in 20 nontumoral hemispheres. RESULTS: In tumoral hemispheres, the distances between the peri-insular sulci and the lateral surface of the IFOF and uncinate fasciculus were enlarged (p < 0.05). Also in tumoral hemispheres, the IFOF was identified in 10 (90.9%) of 11 patients with an extent of resection less than 80%, and in 4 (36.4%) of 11 patients with an extent of resection equal to or greater than 80% (multivariate analysis: p = 0.03). CONCLUSIONS: Insular gliomas grow in the space between the lateral surface of the IFOF and uncinate fasciculus and the insular surface, displacing and compressing the tracts medially. Moreover, these tracts may be completely infiltrated by the tumor, with a total disruption of the bundles. In the current study, the identification of the IFOF with DTI tractography was significantly associated with the extent of tumor resection. If the IFOF is not identified preoperatively, there is a high probability of achieving a resection greater than 80%.


Asunto(s)
Neoplasias Encefálicas/patología , Corteza Cerebral/anatomía & histología , Imagen de Difusión Tensora , Glioma/patología , Adulto , Anciano , Neoplasias Encefálicas/cirugía , Cadáver , Femenino , Glioma/cirugía , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
17.
J Neurol Sci ; 327(1-2): 75-9, 2013 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-23465508

RESUMEN

Idiopathic CD4 lymphocytopenia (ICL) is a syndrome described in patients with low counts of CD4 cells and no other causes for immunosuppression. A few cases of progressive multifocal leukoencephalopathy (PML) have been described in association with this entity. There is no effective treatment for any of them, and the clinical course and outcome are unpredictable. We report on a case of ICL with PML and review the literature, trying to identify the clinical features and the prognosis clues associated to these entities together. A 72-year-old man presented with acute onset gait instability that progressed to a severe cerebellar syndrome with cognitive decline. A cranial MRI showed findings consistent with PML, this diagnosis being confirmed by CSF analyses. Absolute number of CD4+ was 242 cells/µL. An extensive work-up including HIV tests was negative. Ten cases of PML and ICL have previously been reported. Factors contributing to the different outcomes are unknown. Although an effective treatment does not exist for PML, it has been recently demonstrated in vitro that several 5HT2A-receptor antagonists block the JC virus infection. Our patient greatly improved and remains stable 34 months after onset; we describe the potential role of mirtazapine in the treatment of PML.


Asunto(s)
Leucoencefalopatía Multifocal Progresiva/complicaciones , Leucoencefalopatía Multifocal Progresiva/diagnóstico , Linfocitopenia-T Idiopática CD4-Positiva/complicaciones , Linfocitopenia-T Idiopática CD4-Positiva/diagnóstico , Anciano , Humanos , Masculino
18.
Brain Struct Funct ; 218(1): 105-21, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22422148

RESUMEN

The anatomy of the perisylvian component of the superior longitudinal fasciculus (SLF) has recently been reviewed by numerous diffusion tensor imaging tractography (DTI) studies. However, little is known about the exact cortical terminations of this tract. The aim of the present work is to isolate the different subcomponents of this tract with fiber dissection and DTI tractography, and to identify the exact cortical connections. Twelve postmortem human hemispheres (6 right and 6 left) were dissected using the cortex-sparing fiber dissection. In addition, three healthy brains were analyzed using DTI-based tractography software. The different components of the perisylvian SLF were isolated and the fibers were followed until the cortical terminations. Three segments of the perisylvian SLF were identified: (1) anterior segment, connecting the supramarginal gyrus and superior temporal gyrus with the precentral gyrus, (2) posterior segment, connecting the posterior portion of the middle temporal gyrus with the angular gyrus, and (3) long segment of the arcuate fasciculus that connects the middle and inferior temporal gyri with the precentral gyrus and posterior portion of the inferior and middle frontal gyri. In the present study, three different components of the perisylvian SLF were identified. For the first time, our dissections revealed that each component was connected to a specific cortical area within the frontal, parietal and temporal lobes. By accurately depicting not only the trajectory but also cortical connections of this bundle, it is possible to develop new insights into the putative functional role of this tract.


Asunto(s)
Corteza Cerebral/citología , Imagen de Difusión Tensora , Disección , Vías Nerviosas/citología , Técnicas de Trazados de Vías Neuroanatómicas , Adulto , Anciano , Cadáver , Lóbulo Frontal/citología , Humanos , Persona de Mediana Edad , Lóbulo Parietal/citología , Lóbulo Temporal/citología , Adulto Joven
19.
J Neurosurg ; 117(5): 844-50, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22957529

RESUMEN

Foix-Chavany-Marie syndrome (FCMS) is a rare type of suprabulbar palsy characterized by an automatic-voluntary dissociation of the orofacial musculature. Here, the authors report an original case of FCMS that occurred intraoperatively while resecting the pars opercularis of the inferior frontal gyrus. This 25-year-old right-handed man with an incidentally diagnosed right frontotemporoinsular tumor underwent surgery using an asleep-awake-asleep technique with direct cortical and subcortical electrical stimulation and a transopercular approach to the insula. While resecting the anterior part of the pars opercularis the patient suffered sudden anarthria and bilateral facial weakness. He was unable to speak or show his teeth on command, but he was able to voluntarily move his upper and lower limbs. This syndrome lasted for 8 days. Postoperative diffusion tensor imaging tractography revealed that connections of the pars opercularis of the right inferior frontal gyrus with the frontal aslant tract (FAT) and arcuate fasciculus (AF) were damaged. This case supplies evidence for localizing the structural substrate of FCMS. It was possible, for the first time in the literature, to accurately correlate the occurrence of FCMS to the resection of connections between the FAT and AF, and the right pars opercularis of the inferior frontal gyrus. The FAT has been recently described, but it may be an important connection to mediate supplementary motor area control of orofacial movement. The present case also contributes to our knowledge of complication avoidance in operculoinsular surgery. A transopercular approach to insuloopercular gliomas can generate FCMS, especially in cases of previous contralateral lesions. The prognosis is favorable, but the patient should be informed of this particular hazard, and the surgeon should anticipate the surgical strategy in case the syndrome occurs intraoperatively in an awake patient.


Asunto(s)
Trastornos de Deglución/etiología , Trastornos de Deglución/fisiopatología , Disartria/etiología , Disartria/fisiopatología , Encefalomielitis Aguda Diseminada/etiología , Encefalomielitis Aguda Diseminada/fisiopatología , Parálisis Facial/etiología , Parálisis Facial/fisiopatología , Lóbulo Frontal/fisiopatología , Lóbulo Frontal/cirugía , Complicaciones Intraoperatorias/fisiopatología , Corteza Motora/fisiopatología , Complicaciones Posoperatorias/fisiopatología , Adulto , Mapeo Encefálico , Neoplasias Encefálicas/cirugía , Imagen de Difusión Tensora , Estimulación Eléctrica , Glioma/cirugía , Humanos , Imagen por Resonancia Magnética , Masculino , Movimiento , Vías Nerviosas/patología , Neuronavegación , Pronóstico , Resultado del Tratamiento
20.
Am J Psychiatry ; 167(4): 451-8, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20160006

RESUMEN

OBJECTIVE: Impaired cognitive function has been identified as a core feature of schizophrenia. However, a significant proportion of patients do not show any cognitive deficits. The aim of this study was to assess if there were differences in white matter integrity between patients with and without cognitive impairment. METHOD: A diffusion tensor imaging study and neurocognitive assessment were conducted in 49 patients with first-episode psychosis and 41 healthy comparison subjects. Subjects were assessed using the Continuous Performance Test, the Grooved Pegboard Test, the Rey Auditory Verbal Learning Test, and the Trail Making Test Part B. For each test, the patient sample was subdivided according to performance, with those scoring more than one standard deviation below the normative mean categorized as impaired. For each cognitive domain, white matter fractional anisotropy in deficit and nondeficit subgroups was compared using a voxel-based analysis. A nonparametric statistical method, controlling for multiple comparisons, was applied. RESULTS: Impairment on the Trail Making Test Part B was associated with reduced fractional anisotropy in the right/left anterior thalamic radiation and inferior fronto-occipital fasciculus, forceps minor, and left superior and inferior longitudinal fasciculi. Patients exhibiting Grooved Pegboard Test impairment showed reduced fractional anisotropy in the forceps minor, inferior fronto-occipital fasciculus, anterior thalamic radiation, and corticospinal and corticopontine tracts. Impaired performance on the Rey Auditory Verbal Learning Test and Continuous Performance Test was not associated with significant differences in fractional anisotropy. CONCLUSION: Deficits in executive and motor functioning in patients with first-episode psychosis are associated with reductions in white matter integrity in the major fasciculi that connect the frontal and temporal cortices as well as in pathways connecting cortical and subcortical regions. Their presence at the onset of illness, in minimally medicated patients, indicates that these findings are not attributable to effects of chronic illness or its treatment.


Asunto(s)
Encéfalo/anatomía & histología , Trastornos del Conocimiento/diagnóstico , Trastornos del Conocimiento/etiología , Trastornos Psicóticos/psicología , Adolescente , Adulto , Femenino , Lateralidad Funcional/fisiología , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Desempeño Psicomotor/fisiología , Índice de Severidad de la Enfermedad , Adulto Joven
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