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1.
BMC Pregnancy Childbirth ; 21(1): 306, 2021 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-33863296

RESUMEN

BACKGROUND: Etiopathogenesis of preterm birth (PTB) is multifactorial, with a universe of risk factors interplaying between the mother and the environment. It is of utmost importance to identify the most informative factors in order to estimate the degree of PTB risk and trace an individualized profile. The aims of the present study were: 1) to identify all acknowledged risk factors for PTB and to select the most informative ones for defining an accurate model of risk prediction; 2) to verify predictive accuracy of the model and 3) to identify group profiles according to the degree of PTB risk based on the most informative factors. METHODS: The Maternal Frailty Inventory (MaFra) was created based on a systematic review of the literature including 174 identified intrauterine (IU) and extrauterine (EU) factors. A sample of 111 pregnant women previously categorized in low or high risk for PTB below 37 weeks, according to ACOG guidelines, underwent the MaFra Inventory. First, univariate logistic regression enabled p-value ordering and the Akaike Information Criterion (AIC) selected the model including the most informative MaFra factors. Second, random forest classifier verified the overall predictive accuracy of the model. Third, fuzzy c-means clustering assigned group membership based on the most informative MaFra factors. RESULTS: The most informative and parsimonious model selected through AIC included Placenta Previa, Pregnancy Induced Hypertension, Antibiotics, Cervix Length, Physical Exercise, Fetal Growth, Maternal Anxiety, Preeclampsia, Antihypertensives. The random forest classifier including only the most informative IU and EU factors achieved an overall accuracy of 81.08% and an AUC of 0.8122. The cluster analysis identified three groups of typical pregnant women, profiled on the basis of the most informative IU and EU risk factors from a lower to a higher degree of PTB risk, which paralleled time of birth delivery. CONCLUSIONS: This study establishes a generalized methodology for building-up an evidence-based holistic risk assessment for PTB to be used in clinical practice. Relevant and essential factors were selected and were able to provide an accurate estimation of degree of PTB risk based on the most informative constellation of IU and EU factors.


Asunto(s)
Nacimiento Prematuro/epidemiología , Adolescente , Adulto , Femenino , Humanos , Persona de Mediana Edad , Embarazo , Nacimiento Prematuro/etiología , Factores de Riesgo , Adulto Joven
2.
Brain Behav ; 9(1): e01159, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30485713

RESUMEN

INTRODUCTION: While cross-sectional studies have shown neural changes in long-term meditators, they might be confounded by self-selection and potential baseline differences between meditators and non meditators. Prospective longitudinal studies of the effects of meditation in naïve subjects are more conclusive with respect to causal inferences, but related evidence is so far limited. METHODS: Here, we assessed the effects of a 4-week Sahaja Yoga meditation training on gray matter density and spontaneous resting-state brain activity in a group of 12 meditation-naïve healthy adults. RESULTS: Compared with 30 control subjects, the participants to meditation training showed increased gray matter density and changes in the coherence of intrinsic brain activity in two adjacent regions of the right inferior frontal gyrus encompassing the anterior component of the executive control network. Both these measures correlated with self-reported well-being scores in the meditation group. CONCLUSIONS: The significant impact of a brief meditation training on brain regions associated with attention, self-control, and self-awareness may reflect the engagement of cognitive control skills in searching for a state of mental silence, a distinctive feature of Sahaja Yoga meditation. The manifold implications of these findings involve both managerial and rehabilitative settings concerned with well-being and emotional state in normal and pathological conditions.


Asunto(s)
Función Ejecutiva/fisiología , Sustancia Gris , Meditación/métodos , Corteza Prefrontal , Yoga , Adulto , Atención/fisiología , Estudios Transversales , Femenino , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/fisiología , Humanos , Masculino , Evaluación de Resultado en la Atención de Salud , Corteza Prefrontal/diagnóstico por imagen , Corteza Prefrontal/fisiología , Estudios Prospectivos , Autocontrol , Adulto Joven
3.
Artículo en Inglés | MEDLINE | ID: mdl-29079138

RESUMEN

BACKGROUND: The Homer family of postsynaptic scaffolding proteins plays a crucial role in glutamate-mediated synaptic plasticity, a phenotype associated with Bipolar Disorder (BD). Homer is a target for antidepressants and mood stabilizers. The AA risk genotype of the Homer rs7713917 A>G SNP has been associated with mood disorders and suicide, and in healthy humans with brain function. Despite the evidence linking Homer 1 gene and function to mood disorder, as well as its involvement in animal models of depression, no study has yet investigated the role of Homer in bipolar depression and treatment response. METHODS: We studied 199 inpatients, affected by a major depressive episode in course of BD. 147 patients were studied with structural MRI of grey and white matter, and 50 with BOLD functional MRI of emotional processing. 158 patients were treated with combined total sleep deprivation and light therapy. RESULTS: At neuroimaging, patients with the AA genotype showed lower grey matter volumes in medial prefrontal cortex, higher BOLD fMRI neural responses to emotional stimuli in anterior cingulate cortex, and lower fractional anisotropy in bilateral frontal WM tracts. Lithium treatment increased axial diffusivity more in AA patients than in G*carriers. At clinical evaluation, the same AA homozygotes showed a worse antidepressant response to combined SD and LT. CONCLUSIONS: rs7713917 influenced brain grey and white matter structure and function in BD, long term effects of lithium on white matter structure, and antidepressant response to chronotherapeutics, thus suggesting that glutamatergic neuroplasticity and Homer 1 function might play a role in BD psychopathology and response to treatment.


Asunto(s)
Antidepresivos/uso terapéutico , Trastorno Bipolar/genética , Trastorno Bipolar/terapia , Encéfalo/efectos de los fármacos , Proteínas de Andamiaje Homer/genética , Compuestos de Litio/uso terapéutico , Trastorno Bipolar/diagnóstico por imagen , Trastorno Bipolar/fisiopatología , Encéfalo/diagnóstico por imagen , Encéfalo/fisiopatología , Mapeo Encefálico , Circulación Cerebrovascular/efectos de los fármacos , Circulación Cerebrovascular/fisiología , Trastorno Depresivo Mayor/diagnóstico por imagen , Trastorno Depresivo Mayor/tratamiento farmacológico , Trastorno Depresivo Mayor/genética , Trastorno Depresivo Mayor/fisiopatología , Imagen de Difusión Tensora , Emociones/efectos de los fármacos , Emociones/fisiología , Femenino , Variación Genética , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/efectos de los fármacos , Sustancia Gris/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Imagen Multimodal , Pruebas Neuropsicológicas , Oxígeno/sangre , Fototerapia , Privación de Sueño , Resultado del Tratamiento , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/efectos de los fármacos , Sustancia Blanca/patología , Sustancia Blanca/fisiopatología , Población Blanca/genética
4.
Neurology ; 89(12): 1265-1273, 2017 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-28821687

RESUMEN

OBJECTIVE: To explore the structural and functional integrity of the sustained attention system in patients with pediatric multiple sclerosis (MS) and its effect on cognitive impairment. METHODS: We enrolled 57 patients with pediatric MS and 14 age- and sex-matched healthy controls (HCs). Patients with >3 abnormal tests at neuropsychological evaluation were classified as cognitively impaired (CI). Sustained attention system activity was studied with fMRI during the Conners Continuous Performance Test (CCPT). Structural integrity of attention network connections was quantified with diffusion tensor (DT) MRI. RESULTS: Within-group analysis showed similar patterns of recruitment of the attention network in HCs and patients with pediatric MS. Diffuse network DT MRI structural abnormalities were found in patients with MS. During CCPT, with increasing task demand, patients with pediatric MS showed increased activation of the left thalamus, anterior insula, and anterior cingulate cortex (ACC) and decreased recruitment of the right precuneus compared to HCs. Thirteen patients (23%) were classified as CI. Compared to cognitively preserved patients, CI patients with pediatric MS had decreased recruitment of several areas located mainly in parietal and occipital lobes and cerebellum and increased deactivation of the ACC, combined with more severe structural damage of white matter tracts connecting these regions. CONCLUSIONS: Our results suggest that the age-expected level of sustained attention system functional competence is achieved in patients with pediatric MS. Inefficient regulation of the functional interaction between different areas of this system, due to abnormal white matter integrity, may result in global cognitive impairment in these patients.


Asunto(s)
Atención/fisiología , Cerebelo/fisiopatología , Corteza Cerebral/fisiopatología , Disfunción Cognitiva/fisiopatología , Esclerosis Múltiple , Desempeño Psicomotor/fisiología , Tálamo/fisiopatología , Sustancia Blanca/patología , Adolescente , Cerebelo/diagnóstico por imagen , Corteza Cerebral/diagnóstico por imagen , Niño , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/etiología , Imagen de Difusión Tensora , Femenino , Giro del Cíngulo/diagnóstico por imagen , Giro del Cíngulo/fisiopatología , Humanos , Imagen por Resonancia Magnética , Masculino , Esclerosis Múltiple/complicaciones , Esclerosis Múltiple/diagnóstico por imagen , Esclerosis Múltiple/patología , Tálamo/diagnóstico por imagen , Sustancia Blanca/diagnóstico por imagen
5.
Endocrine ; 57(1): 138-147, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27688008

RESUMEN

Resection of large lesions growing into the third ventricle is considered nowadays still a demanding surgery, due to the high risk of severe endocrine and neurological complications. Some neurosurgical approaches were considered in the past the procedures of choice to access the third ventricle, however they were burden by endocrine and neurological consequences, like memory loss and epilepsy. We report here the endocrine and functional results in a series of patients operated with a recently developed approach specifically tailored for the resection of large lesions growing into the third ventricle. Authors conducted a retrospective analysis on 10 patients, operated between 2011 and 2012, for the resection of large tumors growing into the third ventricle. Total resection was achieved in all patients. No perioperative deaths were recorded and all patients were alive after the follow-up. One year after surgery 8/10 patients had an excellent outcome with a Karnofsky Performance Status of 100 and a Glasgow Outcome score of 5, with 8 patients experiencing an improvement of the Body Mass Index. Modern neurosurgery allows a safe and effective treatment of large lesions growing into the third ventricle with a postoperative good functional status.


Asunto(s)
Índice de Masa Corporal , Neoplasias del Ventrículo Cerebral/cirugía , Hipotálamo/cirugía , Tercer Ventrículo/cirugía , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Procedimientos Neuroquirúrgicos , Periodo Posoperatorio , Estudios Retrospectivos , Resultado del Tratamiento
6.
Paediatr Anaesth ; 26(5): 521-30, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26956994

RESUMEN

BACKGROUND: Functional Magnetic Resonance Imaging (fMRI) is often used in preoperative assessment before epilepsy surgery, tumor or cavernous malformation resection, or cochlear implantation. As it requires complete immobility, sedation is needed for uncooperative patients. OBJECTIVE: The aim of this study was to compare the fMRI cortical activation pattern after auditory stimuli in propofol-sedated 5- to 8-year-old children with that of similarly aged nonsedated children. METHODS: When possible, children underwent MRI without sedation, otherwise it was induced with i.v. propofol 2 mg·kg(-1) and maintained with i.v. propofol 4-5 mg·kg(-1) ·h(-1) . Following diagnostic MRI, fMRi was carried out, randomly alternating two passive listening tasks (a fairy-tale and nonsense syllables). RESULTS: We studied 14 awake and 15 sedated children. During the fairy-tale task, the nonsedated children's blood-oxygen-level-dependent (BOLD) signal was bilaterally present in the posterior superior temporal gyrus (STG), Wernicke's area, and Broca's area. Sedated children showed similar activation, with lesser extension to Wernicke's area, and no activation in Broca's area. During the syllable task, the nonsedated children's BOLD signal was bilaterally observed in the STG and Wernicke's area, in Broca's area with leftward asymmetry, and in the premotor area. In sedated children, cortical activation was present in the STG, but not in the frontal lobes. BOLD signal change areas in sedated children were less extended than in nonsedated children during both the fairy-tale and syllable tasks. Modeling the temporal derivative during both the fairy-tale and syllable tasks, nonsedated children showed no response while sedated children did. CONCLUSIONS: After auditory stimuli, propofol-sedated 5- to 8-year-old children exhibit an fMRI cortical activation pattern which is different from that in similarly aged nonsedated children.


Asunto(s)
Sedación Consciente , Audición/fisiología , Hipnóticos y Sedantes , Imagen por Resonancia Magnética/métodos , Propofol , Estimulación Acústica , Niño , Preescolar , Femenino , Lóbulo Frontal/anatomía & histología , Lóbulo Frontal/fisiología , Humanos , Masculino , Oxígeno/sangre , Lóbulo Temporal/anatomía & histología , Lóbulo Temporal/fisiología
7.
Endocrine ; 51(1): 148-62, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26179178

RESUMEN

Quality of life of craniopharyngioma patients can be severely impaired by derangement of hypothalamic function. A classification, taking into account preoperative hypothalamic damage, evaluated by magnetic resonance imaging (MRI), and correlating it with postoperative weight change is still missing in the literature. The aim of our study is to identify objective radiological criteria as preoperative prognostic factors for hypothalamic damage. Pre- and post-operative MRI and clinical data of 47 patients, treated at our Institution for craniopharyngioma, were retrospectively analyzed, based on radiological variables, identified as prognostic factor for hypothalamic involvement. Main factors associated with postoperative obesity were hypothalamic hyperintensity in T2-weighted/FLAIR imaging (p < 0.033), mammillary body involvement according to Müller classification (p < 0.020), unidentifiable pituitary stalk (p < 0.001), dislocated chiasm (p < 0.038), either not visible infundibular recess (p < 0.019) or unrecognizable supra-optic recess (p < 0.004), and retrochiasmatic tumor extension (p < 0.019). Accordingly, postoperative hypothalamic syndrome was associated with peritumoral edema in T2-weighted/FLAIR images (p < 0.003), unidentifiable hypothalamus (p < 0.024), hypothalamic compression (p < 0.006), fornix displacement (p < 0.032), and unrecognizable supra-optic recess (p < 0.031). Ultimately, variables identified as predictive factors of postoperative hypothalamic syndrome were the degree of hypothalamic involvement according to the classification described by Sainte-Rose and Puget (p < 0.002; grade 0 vs 2 p < 0.001), Van Gompel (p < 0.002; grade 0 vs 1, p < 0.027; and grade 0 vs 2, p < 0.002), and Muller (p < 0.006; grade 0 vs 1, p < 0.05; and grade 0 vs 2, p < 0.004). The identification of these predictive factors will help to define and score the preoperative hypothalamic involvement in craniopharyngioma patients.


Asunto(s)
Craneofaringioma/diagnóstico , Craneofaringioma/cirugía , Hipotálamo/fisiopatología , Imagen por Resonancia Magnética , Neoplasias Hipofisarias/diagnóstico , Neoplasias Hipofisarias/cirugía , Adulto , Niño , Craneofaringioma/mortalidad , Craneofaringioma/radioterapia , Femenino , Humanos , Hipotálamo/patología , Masculino , Neoplasias Hipofisarias/mortalidad , Neoplasias Hipofisarias/radioterapia , Valor Predictivo de las Pruebas , Pronóstico , Calidad de Vida , Estudios Retrospectivos , Resultado del Tratamiento
8.
Psychiatry Res ; 233(2): 243-53, 2015 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-26195295

RESUMEN

The identification of antidepressant response predictors in bipolar disorder (BD) may provide new potential enhancements in treatment selection. Repeated total sleep deprivation combined with light therapy (TSD+LT) can acutely reverse depressive symptoms and has been proposed as a model antidepressant treatment. This study aims at investigating the effect of TSD+LT on effective connectivity and neural response in cortico-limbic circuitries during implicit processing of fearful and angry faces in patients with BD. fMRI and Dynamic Causal Modeling (DCM) were combined to study the effect of chronotherapeutics on neural responses in healthy controls (HC, n = 35) and BD patients either responder (RBD, n = 26) or non responder (nRBD, n = 11) to 3 consecutive TSD+LT sessions. Twenty-four DCMs exploring connectivity between anterior cingulate cortex (ACC), dorsolateral prefrontal cortex (DLPFC), Amygdala (Amy), fusiform gyrus and visual cortex were constructed. After treatment, patients significantly increased their neural responses in DLPFC, ACC and insula. nRBD showed lower baseline and endpoint neural responses than RBD. The increased activity in ACC and in medial prefrontal cortex, associated with antidepressant treatment, was positively associated with the improvement of depressive symptomatology. Only RBD patients increased intrinsic connectivity from DLPFC to ACC and reduced the modulatory effect of the task on Amy-DLPFC connection. A successful antidepressant treatment was associated with an increased functional activity and connectivity within cortico-limbic networks, suggesting the possible role of these measures in providing possible biomarkers for treatment efficacy.


Asunto(s)
Trastorno Bipolar/tratamiento farmacológico , Trastorno Depresivo Mayor/tratamiento farmacológico , Cronoterapia de Medicamentos , Interpretación de Imagen Asistida por Computador , Sistema Límbico/efectos de los fármacos , Carbonato de Litio/uso terapéutico , Imagen por Resonancia Magnética , Red Nerviosa/efectos de los fármacos , Fototerapia , Corteza Prefrontal/efectos de los fármacos , Privación de Sueño , Adulto , Trastorno Bipolar/diagnóstico , Trastorno Bipolar/psicología , Terapia Combinada , Trastorno Depresivo Mayor/diagnóstico , Trastorno Depresivo Mayor/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad
9.
Cephalalgia ; 32(2): 109-15, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22174349

RESUMEN

AIM: We assessed the pattern of regional white matter and grey matter abnormalities in patients with cluster headache (CH), using tract-based spatial statistics (TBSS) and voxel-based morphometry (VBM). METHODS: Using a 3.0 Tesla scanner, dual-echo, diffusion tensor and 3D T1-weighted scan were acquired from 15 patients with episodic CH and 19 healthy controls. TBSS analysis was performed using the FMRIB's Diffusion Toolbox. VBM was performed on the 3D T1-weighted images using SPM8. RESULTS: No diffusivity and volumetry abnormalities of brain white matter were detected in CH patients. Compared with controls, CH patients showed decreased grey matter volume in the right thalamus, head of the right caudate nucleus, right precentral gyrus, right posterior cingulate cortex, bilateral middle frontal gyrus, right middle temporal gyrus, left inferior parietal lobule and left insula (p < 0.001). They also had increased grey matter volume of the right cuneus. The results did not change after hemisphere mirroring in the five patients with left lateralized attacks. The decreased left middle frontal gyrus volume was significantly correlated with disease duration (r = -0.79, p < 0.001). CONCLUSION: CH patients experience tissue abnormalities of grey matter regions that are part of the antinociceptive system, which is shared with other chronic pain conditions.


Asunto(s)
Encéfalo/patología , Cefalalgia Histamínica/patología , Imagen de Difusión Tensora , Red Nerviosa/patología , Neuronas/patología , Adulto , Núcleo Caudado/patología , Femenino , Lóbulo Frontal/patología , Lateralidad Funcional , Giro del Cíngulo/patología , Humanos , Hipotálamo/patología , Masculino , Persona de Mediana Edad , Lóbulo Parietal/patología , Tálamo/patología
10.
Psychiatry Res ; 173(3): 238-42, 2009 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-19682864

RESUMEN

Glutamate is the primary excitatory neurotransmitter of the human brain, and recent findings suggest a role for the glutamatergic system in the pathophysiology and treatment of mood disorders. Single proton magnetic resonance spectroscopy (1H-MRS) was used to study the relative in vivo levels of brain neural metabolites. We evaluated the effect of antidepressant treatments on the relative concentration of unresolved glutamate and glutamine (Glx) with GABA contamination (2.35 ppm peak) using single voxel 1H-MRS at 3.0 Tesla. We studied 19 inpatients (7 males, 12 females) affected by bipolar disorder type I, current depressive episode without psychotic features, before and after 1 week of treatment with repeated total sleep deprivation (TSD) combined with light therapy (LT). Chronobiological treatment caused a significant amelioration in mood levels. Changes in the brain Glx/creatine ratio followed a general trend toward decrease, with individual variability. We observed that the decrease in the Glx/creatine ratio significantly correlated with the improvement of both objective and subjective measures of depression.


Asunto(s)
Antidepresivos/uso terapéutico , Trastorno Bipolar , Encéfalo/patología , Fototerapia/métodos , Privación de Sueño/inducido químicamente , Adulto , Trastorno Bipolar/metabolismo , Trastorno Bipolar/patología , Trastorno Bipolar/terapia , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Creatina/metabolismo , Femenino , Ácido Glutámico/metabolismo , Humanos , Imagen por Resonancia Magnética/métodos , Espectroscopía de Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Protones
11.
Arch Gen Psychiatry ; 64(2): 179-87, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17283285

RESUMEN

CONTEXT: Total sleep deprivation combined with light therapy causes rapid amelioration of bipolar depression. A polymorphism in the promoter for the serotonin transporter influences both antidepressant response and the structure and function of specific brain areas. OBJECTIVE: To determine whether antidepressant therapy or the genotype of the serotonin transporter influence the pattern of neural response to a task targeting the depressive biases in information processing (moral valence decision). DESIGN: Before-and-after trial studying the biologic correlates of response to treatment. SETTING: University hospital. Patients Twenty inpatients with bipolar depression. Intervention Repeated total sleep deprivation combined with light therapy for 1 week. MAIN OUTCOME MEASURES: Brain blood oxygen level-dependent functional magnetic resonance imaging using a 3.0-T scanner before and after treatment. Self-ratings and observer ratings of mood (visual analog scale 3 times daily and Hamilton Depression Rating Scale) before and after treatment. RESULTS: We found significant interactions of treatment (before and after), response to treatment (Hamilton Depression Rating Scale score <8), and moral valence of the stimuli (positive or negative) in the anterior cingulate cortex, dorsolateral prefrontal cortex, insula, and parietal cortex. In these areas, responders changed their blood oxygen level-dependent responses to emotional stimuli in a pattern opposite of that in nonresponders. Genotype of the promoter for the serotonin transporter predicted response to treatment and influenced baseline neural responses in the anterior cingulate cortex and the dorsolateral prefrontal cortex. CONCLUSION: Multiple factors that affect or are affected at the individual level by major depressive episodes in the course of bipolar disorder significantly interact in influencing brain cortical activity in specific areas.


Asunto(s)
Trastorno Bipolar/psicología , Trastorno Bipolar/terapia , Corteza Cerebral/fisiología , Cronoterapia/métodos , Juicio , Imagen por Resonancia Magnética/estadística & datos numéricos , Principios Morales , Privación de Sueño , Trastorno Bipolar/fisiopatología , Terapia Combinada , Toma de Decisiones , Trastorno Depresivo Mayor/fisiopatología , Femenino , Genotipo , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Oxígeno/sangre , Fototerapia , Polimorfismo Genético/fisiología , Escalas de Valoración Psiquiátrica/estadística & datos numéricos , Desempeño Psicomotor , Proteínas de Transporte de Serotonina en la Membrana Plasmática/genética , Proteínas de Transporte de Serotonina en la Membrana Plasmática/fisiología , Resultado del Tratamiento
12.
Arch Neurol ; 62(6): 898-902, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15956160

RESUMEN

BACKGROUND: There is an increasing body of evidence that magnetic resonance imaging-occult tissue damage is an important component of primary progressive multiple sclerosis (PPMS) pathology. Proton magnetic resonance spectroscopy (1H-MRS) can be used to measure in vivo whole-brain N-acetylaspartate (WBNAA) concentrations, the decrease of whose levels is considered a marker of neuronal-axonal injury. OBJECTIVES: To study WBNAA 1H-MRS as a tool to provide information about irreversible brain damage in PPMS and to investigate the relationship between WBNAA and other magnetic resonance imaging measures of MS disease burden, including brain atrophy. METHODS: The following magnetic resonance pulse sequences of the brain were obtained from 32 patients with PPMS and 16 age-matched healthy subjects: (1) dual-echo turbo spin-echo; (2) T1-weighted spin-echo; and (3) 1H-MRS to measure WBNAA concentration. Brain total lesion volumes were measured. Normalized brain volumes were calculated using a fully automated technique. Absolute WBNAA amounts were calculated using a phantom replacement method and were then corrected for individual subjects' brain size. RESULTS: Levels of WBNAA concentrations and normalized brain volumes were significantly lower in patients with PPMS (mean values, 10.2 mm and 1500.0 mL, respectively) than in healthy controls (mean values, 12.9 mm and 1585.2 mL). Both WBNAA concentrations and normalized brain volumes were included as independent factors in the final model of a multivariable analysis predicting the subjects' condition. No significant correlations were found between WBNAA values and normalized brain volumes, WBNAA and T2-weighted or T1-weighted lesion volumes. CONCLUSIONS: Axonal-neuronal damage in the brain of patients with PPMS seems to occur, at least partially, independently of the burden of magnetic resonance imaging-visible lesions. Whole-brain N-acetylaspartate values and normalized brain volumes were unrelated in this cohort, thereby suggesting that 1H-MRS and atrophy assessment may provide in vivo complementary information about the actual extent of brain damage in PPMS.


Asunto(s)
Ácido Aspártico/análogos & derivados , Axones/patología , Encéfalo/patología , Esclerosis Múltiple Crónica Progresiva/patología , Adulto , Anciano , Ácido Aspártico/metabolismo , Atrofia , Axones/diagnóstico por imagen , Biomarcadores/metabolismo , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Femenino , Humanos , Espectroscopía de Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple Crónica Progresiva/diagnóstico por imagen , Cintigrafía
13.
Neuroimage ; 18(4): 847-55, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12725761

RESUMEN

Previous work has suggested that functional reorganization of cortical areas might have a role in limiting the clinical impact of axonal pathology in patients with established multiple sclerosis (MS). Since there is evidence for irreversible tissue damage even in patients with early MS, we assessed, using functional MRI (fMRI) and a general search method, the brain pattern of movement-associated cortical activations in patients at presentation with clinically isolated syndromes (CIS) suggestive of MS. To elucidate the role of cortical reorganization in these patients, we also investigated the extent to which the fMRI changes correlated with the extent of overall axonal injury of the brain. From 16 right-handed patients at presentation with CIS and 15 right-handed, age- and sex-matched healthy volunteers, we obtained: (1). fMRI (repetitive flexion-extension of the last four fingers of the right hand), (2). conventional MRI scans, and (3). a new, unlocalized proton MR spectroscopy ((1)HMRS) sequence to measure the concentration of N-acetylaspartate of the whole brain (WBNAA). Compared to controls, patients with CIS had more significant activations of the contralateral primary somatomotor cortex (SMC), secondary somatosensory cortex, and inferior frontal gyrus. They also had significant decreased WBNAA concentration. Relative activation of the contralateral primary SMC was strongly correlated with WBNAA levels (r = -0.78, P < 0.001). This study shows that axonal pathology and functional cortical changes over a rather distributed sensorimotor network occur in patients at presentation with CIS suggestive of MS and that these two aspects of the disease are strictly correlated. This suggests that the increased functional recruitment of the cortex in these patients might have an adaptive role in limiting the clinical impact of irreversible tissue damage.


Asunto(s)
Adaptación Fisiológica , Ácido Aspártico/análogos & derivados , Axones , Corteza Cerebral/fisiopatología , Esclerosis Múltiple/fisiopatología , Enfermedades del Sistema Nervioso/fisiopatología , Adaptación Fisiológica/fisiología , Adulto , Ácido Aspártico/análisis , Ácido Aspártico/metabolismo , Axones/patología , Axones/fisiología , Encéfalo/metabolismo , Encéfalo/patología , Encéfalo/fisiopatología , Mapeo Encefálico , Corteza Cerebral/patología , Femenino , Dedos/fisiología , Lóbulo Frontal/metabolismo , Lóbulo Frontal/patología , Lóbulo Frontal/fisiopatología , Humanos , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/diagnóstico , Esclerosis Múltiple/patología , Red Nerviosa/patología , Red Nerviosa/fisiopatología , Enfermedades del Sistema Nervioso/diagnóstico , Enfermedades del Sistema Nervioso/patología , Desempeño Psicomotor , Valores de Referencia , Corteza Somatosensorial/fisiopatología , Síndrome
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