Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 34
Filtrar
1.
Cancers (Basel) ; 16(10)2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38791976

RESUMEN

This retrospective multicenter study examines therapy-induced orbital and ocular MRI findings in retinoblastoma patients following selective intra-arterial chemotherapy (SIAC) and quantifies the impact of SIAC on ocular and optic nerve growth. Patients were selected based on medical chart review, with inclusion criteria requiring the availability of posttreatment MR imaging encompassing T2-weighted and T1-weighted images (pre- and post-intravenous gadolinium administration). Qualitative features and quantitative measurements were independently scored by experienced radiologists, with deep learning segmentation aiding total eye volume assessment. Eyes were categorized into three groups: eyes receiving SIAC (Rb-SIAC), eyes treated with other eye-saving methods (Rb-control), and healthy eyes. The most prevalent adverse effects post-SIAC were inflammatory and vascular features, with therapy-induced contrast enhancement observed in the intraorbital optic nerve segment in 6% of patients. Quantitative analysis revealed significant growth arrest in Rb-SIAC eyes, particularly when treatment commenced ≤ 12 months of age. Optic nerve atrophy was a significant complication in Rb-SIAC eyes. In conclusion, this study highlights the vascular and inflammatory adverse effects observed post-SIAC in retinoblastoma patients and demonstrates a negative impact on eye and optic nerve growth, particularly in children treated ≤ 12 months of age, providing crucial insights for clinical management and future research.

2.
Front Neurol ; 15: 1358741, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38595845

RESUMEN

Objective: To assess the accuracy of corpus callosum (CC) biometry, including sub-segments, using 3D super-resolution fetal brain MRI (SR) compared to 2D or 3D ultrasound (US) and clinical low-resolution T2-weighted MRI (T2WS). Method: Fetal brain biometry was conducted by two observers on 57 subjects [21-35 weeks of gestational age (GA)], including 11 cases of partial CC agenesis. Measures were performed by a junior observer (obs1) on US, T2WS and SR and by a senior neuroradiologist (obs2) on T2WS and SR. CC biometric regression with GA was established. Statistical analysis assessed agreement within and between modalities and observers. Results: This study shows robust SR to US concordance across gestation, surpassing T2WS. In obs1, SR aligns with US, except for genu and CC length (CCL), enhancing splenium visibility. In obs2, SR closely corresponds to US, differing in rostrum and CCL. The anterior CC (rostrum and genu) exhibits higher variability. SR's regression aligns better with literature (US) for CCL, splenium and body than T2WS. SR is the method with the least missing values. Conclusion: SR yields CC biometry akin to US (excluding anterior CC). Thanks to superior 3D visualization and better through plane spatial resolution, SR allows to perform CC biometry more frequently than T2WS.

3.
Eur Radiol ; 2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-38087063

RESUMEN

OBJECTIVES: To assess the diagnostic accuracy of nerve thickening on MRI to predict early-stage postlaminar optic nerve invasion (PLONI) in retinoblastoma. Furthermore, this study aimed to incorporate measurements into a multiparametric model for radiological determination of PLONI. METHODS: In this retrospective multicenter case-control study, high-spatial-resolution 3D T2-weighted MR images were used to measure the distal optic nerve. Histopathology was the reference standard for PLONI. Two neuroradiologists independently measured the optic nerve width, height, and surface at 0, 3, and 5 mm from the most distal part of the optic nerve. Subsequently, PLONI was scored on contrast-enhanced T1-weighted and 3D T2-weighted images, blinded for clinical data. Optic nerve measurements with the highest diagnostic accuracy for PLONI were incorporated into a prediction model for radiological determination of PLONI. RESULTS: One hundred twenty-four retinoblastoma patients (median age, 22 months [range, 0-113], 58 female) were included, resulting in 25 retinoblastoma eyes with histopathologically proven PLONI and 206 without PLONI. ROC analysis of axial optic nerve width measured at 0 mm yielded the best area under the curve of 0.88 (95% confidence interval: 0.79, 0.96; p < 0.001). The optimal width cutoff was ≥ 2.215 mm, with a sensitivity of 84% (95% CI: 64, 95%) and specificity of 83% (95% CI: 75, 89%) for detecting PLONI. Combining width measurements with the suspicion of PLONI on MRI sequences resulted in a prediction model with an improved sensitivity and specificity of respectively up to 88% and 92%. CONCLUSION: Postlaminar optic nerve thickening can predict early-stage postlaminar optic nerve invasion in retinoblastoma. CLINICAL RELEVANCE STATEMENT: This study provides an additional tool for clinicians to help determine postlaminar optic nerve invasion, which is a risk factor for developing metastatic disease in retinoblastoma patients. KEY POINTS: • The diagnostic accuracy of contrast-enhanced MRI for detecting postlaminar optic nerve invasion is limited in retinoblastoma patients. • Optic nerve thickening can predict postlaminar optic nerve invasion. • A prediction model combining MRI features has a high sensitivity and specificity for detecting postlaminar optic nerve invasion.

4.
Sci Rep ; 12(1): 8682, 2022 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-35606398

RESUMEN

Accurate characterization of in utero human brain maturation is critical as it involves complex and interconnected structural and functional processes that may influence health later in life. Magnetic resonance imaging is a powerful tool to investigate equivocal neurological patterns during fetal development. However, the number of acquisitions of satisfactory quality available in this cohort of sensitive subjects remains scarce, thus hindering the validation of advanced image processing techniques. Numerical phantoms can mitigate these limitations by providing a controlled environment with a known ground truth. In this work, we present FaBiAN, an open-source Fetal Brain magnetic resonance Acquisition Numerical phantom that simulates clinical T2-weighted fast spin echo sequences of the fetal brain. This unique tool is based on a general, flexible and realistic setup that includes stochastic fetal movements, thus providing images of the fetal brain throughout maturation comparable to clinical acquisitions. We demonstrate its value to evaluate the robustness and optimize the accuracy of an algorithm for super-resolution fetal brain magnetic resonance imaging from simulated motion-corrupted 2D low-resolution series compared to a synthetic high-resolution reference volume. We also show that the images generated can complement clinical datasets to support data-intensive deep learning methods for fetal brain tissue segmentation.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Encéfalo/diagnóstico por imagen , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Espectroscopía de Resonancia Magnética , Fantasmas de Imagen
5.
Front Neurol ; 13: 827816, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35585848

RESUMEN

Fetal brain diffusion magnetic resonance images (MRI) are often acquired with a lower through-plane than in-plane resolution. This anisotropy is often overcome by classical upsampling methods such as linear or cubic interpolation. In this work, we employ an unsupervised learning algorithm using an autoencoder neural network for single-image through-plane super-resolution by leveraging a large amount of data. Our framework, which can also be used for slice outliers replacement, overperformed conventional interpolations quantitatively and qualitatively on pre-term newborns of the developing Human Connectome Project. The evaluation was performed on both the original diffusion-weighted signal and the estimated diffusion tensor maps. A byproduct of our autoencoder was its ability to act as a denoiser. The network was able to generalize fetal data with different levels of motions and we qualitatively showed its consistency, hence supporting the relevance of pre-term datasets to improve the processing of fetal brain images.

6.
Front Pediatr ; 9: 639746, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34447726

RESUMEN

We present the comparison of two-dimensional (2D) fetal brain biometry on magnetic resonance (MR) images using orthogonal 2D T2-weighted sequences (T2WSs) vs. one 3D super-resolution (SR) reconstructed volume and evaluation of the level of confidence and concordance between an experienced pediatric radiologist (obs1) and a junior radiologist (obs2). Twenty-five normal fetal brain MRI scans (18-34 weeks of gestation) including orthogonal 3-mm-thick T2WSs were analyzed retrospectively. One 3D SR volume was reconstructed per subject based on multiple series of T2WSs. The two observers performed 11 2D biometric measurements (specifying their level of confidence) on T2WS and SR volumes. Measurements were compared using the paired Wilcoxon rank sum test between observers for each dataset (T2WS and SR) and between T2WS and SR for each observer. Bland-Altman plots were used to assess the agreement between each pair of measurements. Measurements were made with low confidence in three subjects by obs1 and in 11 subjects by obs2 (mostly concerning the length of the corpus callosum on T2WS). Inter-rater intra-dataset comparisons showed no significant difference (p > 0.05), except for brain axial biparietal diameter (BIP) on T2WS and for brain and skull coronal BIP and coronal transverse cerebellar diameter (DTC) on SR. None of them remained significant after correction for multiple comparisons. Inter-dataset intra-rater comparisons showed statistical differences in brain axial and coronal BIP for both observers, skull coronal BIP for obs1, and axial and coronal DTC for obs2. After correction for multiple comparisons, only axial brain BIP remained significantly different, but differences were small (2.95 ± 1.73 mm). SR allows similar fetal brain biometry as compared to using the conventional T2WS while improving the level of confidence in the measurements and using a single reconstructed volume.

7.
Invest Radiol ; 53(2): 70-79, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28906338

RESUMEN

OBJECTIVES: The primary objective of this study was to investigate the pharmacokinetic profile of gadoterate meglumine in pediatric patients younger than 2 years; the secondary objectives were to document its efficacy and safety. MATERIAL AND METHODS: This was a Phase IV open-label, prospective study conducted in 9 centers (4 countries). Forty-five patients younger than 2 years with normal estimated glomerular filtration rate and scheduled to undergo routine gadolinium-enhanced magnetic resonance imaging (MRI) of any organ were included and received a single intravenous injection of gadoterate meglumine (0.1 mmol/kg). To perform the population pharmacokinetics analysis, 3 blood samples per subject were drawn during 3 time windows at time points allocated by randomization. RESULTS: Gadoterate meglumine concentrations were best fitted using a 2-compartmental model with linear elimination from central compartment. The median total clearance adjusted to body weight was estimated at 0.06 L/h per kg and increased with estimated glomerular filtration rate according to a power model. The median volume of distribution at steady state (Vss) adjusted to body weight was estimated at 0.047 L/kg. Estimated median terminal half-life (t1/2ß) was 1.35 h, and the median systemic exposure (area under the curve) was 1591 µmol h/L. Efficacy was assessed by comparing precontrast +postcontrast images to precontrast images in a subset of 28 subjects who underwent an MRI examination of brain, spine, and associated tissues. A total of 28 lesions were identified and analyzed in 15 subjects with precontrast images versus 30 lesions in 16 subjects with precontrast + postcontrast images. Lesion visualization was improved with a mean (SD) increase in scores at subject level of 0.7 (1.0) for lesion border delineation, 0.9 (1.6) for internal morphology, and 3.1 (3.2) for contrast enhancement. Twenty-six adverse events occurred postinjection in 13 subjects (28.9%), including 3 serious reported in 1 subject (2.2%). One subject (2.2%) experienced 1 rash of moderate intensity considered as related to gadoterate meglumine. CONCLUSIONS: The pharmacokinetic profile of gadoterate meglumine after a single intravenous injection of 0.1 mmol/kg was appropriately described in newborns and infants younger than 2 years, for whom no dose adjustment is required. The improved efficacy of gadoterate meglumine for contrast-enhanced MRI examination of brain, spine, and associated tissues, as well as its good safety profile, was also demonstrated in this population.


Asunto(s)
Medios de Contraste/farmacocinética , Aumento de la Imagen/métodos , Meglumina/farmacocinética , Compuestos Organometálicos/farmacocinética , Encéfalo/diagnóstico por imagen , Medios de Contraste/efectos adversos , Femenino , Gadolinio , Tasa de Filtración Glomerular , Humanos , Lactante , Recién Nacido , Inyecciones Intravenosas , Imagen por Resonancia Magnética/métodos , Masculino , Meglumina/efectos adversos , Compuestos Organometálicos/efectos adversos , Estudios Prospectivos , Columna Vertebral/diagnóstico por imagen
9.
Parkinsonism Relat Disord ; 39: 4-16, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28256436

RESUMEN

INTRODUCTION: Parkinsonian-Pyramidal syndrome (PPS), defined as the combination of both pyramidal and parkinsonian signs is a concept that recently emerged. PPS may manifest itself in numerous neurodegenerative diseases, many of these being inherited. Their diagnosis is a major challenge for the clinical management, for the prognosis, for genetic counselling and, in a few cases, which should not be neglected, for specific treatment. OBJECTIVE: Our objective is to provide a review of PPS and an algorithm in order to guide their diagnosis in clinical practice. METHODS: We performed an exhaustive PubMed and OMIM research matching the following key words: "Parkinsonism and pyramidal signs" or "Parkinsonism and spasticity" or "pallido-pyramidal syndrome" or "Parkinsonism and spastic paraplegia". English publications from the last ten years were included. RESULTS: We propose a pragmatic presentation based on several established classifications and we will distinguish inherited PPS found in complex hereditary spastic paraplegia, young onset parkinsonism, neurodegeneration with brain iron accumulation, primary familial brain calcifications, inborn errors of metabolism, and few rare others inherited neurodegenerative diseases, then non-inherited neurodegenerative PPS. We therefore suggest guidelines (based on age at onset, family history, associated clinical signs, brain MRI findings as well as certain laboratory investigations), for the diagnosis and the management of PPS. Many pathophysiological pathways may underlie PPS but the most frequent are those usually involved in both inherited Parkinson's disease and spastic paraplegia, i.e. mitochondrial pathway, vesicular trafficking including endosomal and lysosomal pathways as well as autophagy.


Asunto(s)
Blefaroespasmo , Enfermedad de Parkinson Secundaria , Trastornos Parkinsonianos , Blefaroespasmo/complicaciones , Blefaroespasmo/diagnóstico , Blefaroespasmo/genética , Encéfalo/diagnóstico por imagen , Bases de Datos Bibliográficas/estadística & datos numéricos , Globo Pálido , Humanos , Imagen por Resonancia Magnética , Enfermedad de Parkinson Secundaria/complicaciones , Enfermedad de Parkinson Secundaria/diagnóstico , Enfermedad de Parkinson Secundaria/genética , Trastornos Parkinsonianos/complicaciones , Trastornos Parkinsonianos/diagnóstico , Trastornos Parkinsonianos/genética
11.
Eur Radiol ; 27(5): 1812-1821, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-27553925

RESUMEN

OBJECTIVES: To describe and evaluate an additional sonographic sign in the diagnosis of biliary atresia (BA), the microcyst of the porta hepatis, in comparison with previously described signs. METHODS: Ultrasound performed in 321 infants (mean age 55 days) with cholestasis were retrospectively analyzed. BA was surgically confirmed in 193 patients and excluded in 128. US evaluated gallbladder type (1: normal; 2: consistent with BA; 3: suspicious), triangular cord sign (TCS), microcyst and macrocyst, polysplenia syndrome, portal hypertension, and bile duct dilatation. T test and Pearson χ2 test were used to compare US signs between the two groups, followed by univariate regression analysis. RESULTS: The highest specificity and sensitivity for BA (p < 0.001) were respectively obtained with non-visible gallbladder (100 %-13 %), macrocyst (99 %-10 %), polysplenia (99 %-11 %), microcyst (98 %-20 %), type 2 gallbladder (98 %-34 %), and TCS (97 %-30 %). Combination of signs (macro or microcyst; cyst and no bile duct dilatation; microcyst and/or TCS; type 2 gallbladder and/or cyst) provided better sensitivities (25-49 %) with similar specificities (95-98 %) (p < 0.001). On univariate analysis, the single US signs most strongly associated with BA were polysplenia (odds ratio, OR 16.3), macrocyst (OR 14.7), TCS (OR 13.4) and microcyst (OR 8). CONCLUSIONS: Porta hepatis microcyst is a reliable US sign for BA diagnosis. KEY POINTS: • The porta hepatis microcyst is a specific sign of biliary atresia. • It was found in 31 (16.1 %) of 193 patients with biliary atresia. • Its specificity was 98 % (p < 0.001). • High frequency transducer and color Doppler can show the porta hepatis microcyst.


Asunto(s)
Enfermedades de los Conductos Biliares/diagnóstico por imagen , Atresia Biliar/diagnóstico por imagen , Colestasis/diagnóstico por imagen , Quistes/diagnóstico por imagen , Vesícula Biliar/diagnóstico por imagen , Síndrome de Heterotaxia/diagnóstico por imagen , Hipertensión Portal/diagnóstico por imagen , Hígado/diagnóstico por imagen , Enfermedades de los Conductos Biliares/complicaciones , Atresia Biliar/complicaciones , Colestasis/complicaciones , Quistes/complicaciones , Dilatación Patológica/complicaciones , Dilatación Patológica/diagnóstico por imagen , Femenino , Síndrome de Heterotaxia/complicaciones , Humanos , Hipertensión Portal/complicaciones , Lactante , Recién Nacido , Masculino , Estudios Retrospectivos , Sensibilidad y Especificidad , Ultrasonografía
12.
Eur J Pediatr Surg ; 27(2): 177-180, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27065355

RESUMEN

Background The prosthesis commonly used for the treatment of congenital diaphragmatic hernia (CDH) lacks elasticity to replace the diaphragm's mechanical properties and does not follow the natural growth of the child treated. Objective To determine the appropriate properties required for the prostheses, a CT study on healthy patients was conducted. Methods Two methods of diaphragmatic surface analysis are assessed: the diaphragmatic surface is either estimated using surface 2D estimations (method 1), or calculated using length measures on thoracoabdominal CT scans from children (method 2). Patients are divided into two groups depending on their age: group 1: n = 9; median age: 2.0 months (0.1-9.5); group 2: n = 9; median age: 182.6 months (158.5-235.5). Growth factor between the two groups is calculated and the two methods are statistically compared. Results The ratio group 2/group 1 of the diaphragmatic surfaces was 4.3 ± 0.2 on the left side and 4.0 ± 0.2 on the right side for method 1, and 5.1 ± 0.2 on the left side and 5.1 ± 0.3 on the right side for method 2. The difference in the median values between both methods is statistically significant for both the left and right sides (p = 0.022 and p = 0.002, respectively). Hence, the two methods cannot be used exchangeably. Conclusion The treatment of CDH with large defect remains a challenge because of the high incidence of hernia recurrence probably due to prosthesis defect; thus it is important to estimate the diaphragmatic surface precisely. We aim to develop a prosthesis material that can be commonly used and found a mean diaphragmatic growth factor of approximately 4 to 5 from early childhood to adolescence.


Asunto(s)
Diafragma/crecimiento & desarrollo , Hernias Diafragmáticas Congénitas/terapia , Tomografía Computarizada por Rayos X/métodos , Adolescente , Diafragma/anatomía & histología , Diafragma/diagnóstico por imagen , Humanos , Lactante , Prótesis e Implantes/efectos adversos , Estudios Retrospectivos , Estadísticas no Paramétricas
13.
Br J Radiol ; 89(1067): 20151033, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27643390

RESUMEN

OBJECTIVE: Cockayne syndrome (CS) is a rare disorder characterized by severe brain atrophy, white matter (WM) hypomyelination and basal ganglia calcifications. This study aimed to quantify atrophy and WM abnormalities using diffusion tensor imaging (DTI) and volumetric analysis, to evaluate possible differences between CS subtypes and to determine whether DTI findings may correspond to a hypomyelinating disorder. METHODS: 14 patients with CS and 14 controls underwent brain MRI including DTI and a volumetric three-dimensional T1 weighted sequence. DTI analysis was made through regions of interest within the whole brain to obtain fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values and in the left centrum semiovale to obtain DTI eigenvalues. The Student's t-test was used to compare patients and controls, and CS subtypes. Given the small number of patients with CS, they were pooled into two groups: moderate (CS1/CS3) and severe (CS2/cerebro-oculo-facio-skeletal syndrome). RESULTS: Total brain volume in CS was reduced by 57%, predominantly in the infratentorial area (68%) (p < 0.001). Total brain volume reduction was greater in the severe group, but there was no difference in the degree of infratentorial atrophy in the two groups (p = 0.7). Mean FA values were lower, whereas ADC was higher in most of the WM in patients with CS (p < 0.05). ADC in the splenium of the corpus callosum and the posterior limb of the internal capsule and FA in the cerebral peduncles were significantly different between the two groups (p < 0.05). Mean ADC values corresponded to a hypomyelinating disorder. All DTI eigenvalues were higher in patients with CS, mainly for transverse diffusivity (+51%) (p < 0.001). CONCLUSION: DTI and volumetric analysis provide quantitative information for the characterization of CS and may be particularly useful for evaluating therapeutic intervention. Advances in knowledge: DTI combined with volumetric analysis provides additional information useful for not only the characterization of CS and distinction of clinical subtypes but also monitoring of therapeutic interventions.


Asunto(s)
Síndrome de Cockayne/diagnóstico por imagen , Imagen de Difusión Tensora/métodos , Adolescente , Adulto , Anisotropía , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Humanos , Interpretación de Imagen Asistida por Computador , Imagenología Tridimensional , Lactante , Masculino
14.
PLoS One ; 11(8): e0160990, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27547969

RESUMEN

Preterm birth represents a high risk of neurodevelopmental disabilities when associated with white-matter damage. Recent studies have reported cognitive deficits in children born preterm without brain injury on MRI at term-equivalent age. Understanding the microstructural and metabolic underpinnings of these deficits is essential for their early detection. Here, we used diffusion-weighted imaging and single-voxel 1H magnetic resonance spectroscopy (MRS) to compare brain maturation at term-equivalent age in premature neonates with no evidence of white matter injury on conventional MRI except diffuse excessive high-signal intensity, and normal term neonates. Thirty-two infants, 16 term neonates (mean post-conceptional age at scan: 39.8±1 weeks) and 16 premature neonates (mean gestational age at birth: 29.1±2 weeks, mean post-conceptional age at scan: 39.2±1 weeks) were investigated. The MRI/MRS protocol performed at 1.5T involved diffusion-weighted MRI and localized 1H-MRS with the Point RESolved Spectroscopy (PRESS) sequence. Preterm neonates showed significantly higher ADC values in the temporal white matter (P<0.05), the occipital white matter (P<0.005) and the thalamus (P<0.05). The proton spectrum of the centrum semiovale was characterized by significantly lower taurine/H2O and macromolecules/H2O ratios (P<0.05) at a TE of 30 ms, and reduced (creatine+phosphocreatine)/H2O and (glutamine+glutamate)/H2O ratios (P<0.05) at a TE of 135 ms in the preterm neonates than in full-term neonates. Our findings indicate that premature neonates with normal conventional MRI present a delay in brain maturation affecting the white matter and the thalamus. Their brain metabolic profile is characterized by lower levels of creatine, glutamine plus glutamate, and macromolecules in the centrum semiovale, a finding suggesting altered energy metabolism and protein synthesis.


Asunto(s)
Disfunción Cognitiva/metabolismo , Recien Nacido Prematuro , Lóbulo Occipital/metabolismo , Lóbulo Temporal/metabolismo , Tálamo/metabolismo , Sustancia Blanca/metabolismo , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/fisiopatología , Creatina/metabolismo , Imagen de Difusión por Resonancia Magnética , Femenino , Ácido Glutámico/metabolismo , Glutamina/metabolismo , Humanos , Lactante , Recién Nacido , Recién Nacido de muy Bajo Peso , Masculino , Lóbulo Occipital/diagnóstico por imagen , Lóbulo Occipital/fisiopatología , Espectroscopía de Protones por Resonancia Magnética , Estudios Retrospectivos , Taurina/metabolismo , Lóbulo Temporal/diagnóstico por imagen , Lóbulo Temporal/fisiopatología , Nacimiento a Término , Tálamo/diagnóstico por imagen , Tálamo/fisiopatología , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/fisiopatología
15.
Handb Clin Neurol ; 136: 1091-119, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27430460

RESUMEN

Numerous events are involved in brain development, some of which are detected by neuroimaging. Major changes in brain morphology are depicted by brain imaging during the fetal period while changes in brain composition can be demonstrated in both pre- and postnatal periods. Although ultrasonography and computed tomography can show changes in brain morphology, these techniques are insensitive to myelination that is one of the most important events occurring during brain maturation. Magnetic resonance imaging (MRI) is therefore the method of choice to evaluate brain maturation. MRI also gives insight into the microstructure of brain tissue through diffusion-weighted imaging and diffusion tensor imaging. Metabolic changes are also part of brain maturation and are assessed by proton magnetic resonance spectroscopy. Understanding and knowledge of the different steps in brain development are required to be able to detect morphologic and structural changes on neuroimaging. Consequently alterations in normal development can be depicted.


Asunto(s)
Encéfalo/diagnóstico por imagen , Encéfalo/crecimiento & desarrollo , Neuroimagen , Humanos , Procesamiento de Imagen Asistido por Computador
16.
PLoS One ; 11(4): e0152475, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27097323

RESUMEN

Cerebral aspergillosis is associated with a significant morbidity and mortality rate. The imaging data present different patterns and no full consensus exists on typical imaging characteristics of the cerebral lesions. We reviewed MRI findings in 21 patients with cerebral aspergillosis and correlated them to the immune status of the patients and to neuropathological findings when tissue was available. The lesions were characterized by their number, topography, and MRI signal. Dissemination to the brain resulted from direct spread from paranasal sinuses in 8 patients, 6 of them being immunocompetent. Hematogenous dissemination was observed in 13 patients, all were immunosuppressed. In this later group we identified a total of 329 parenchymal abscesses involving the whole brain with a predilection for the corticomedullary junction. More than half the patients had a corpus callosum lesion. Hemorrhagic lesions accounted for 13% and contrast enhancement was observed in 61% of the lesions. Patients with hematogenous dissemination were younger (p = 0.003), had more intracranial lesions (p = 0.0004) and had a higher 12-week mortality rate (p = 0.046) than patients with direct spread from paranasal sinuses. Analysis of 12 aneurysms allowed us to highlight two distinct situations. In case of direct spread from the paranasal sinuses, aneurysms are saccular and located on the proximal artery portions, while the hematogenous dissemination in immunocompromised patients is more frequently associated with distal and fusiform aneurysms. MRI is the exam of choice for cerebral aspergillosis. Number and type of lesions are different according to the mode of dissemination of the infection.


Asunto(s)
Encefalopatías/diagnóstico , Encefalopatías/patología , Imagen por Resonancia Magnética , Neuroaspergilosis/diagnóstico , Neuroaspergilosis/patología , Adulto , Anciano , Encefalopatías/complicaciones , Encefalopatías/inmunología , Humanos , Masculino , Persona de Mediana Edad , Neuroaspergilosis/complicaciones , Neuroaspergilosis/inmunología , Senos Paranasales/microbiología , Pronóstico , Estudios Retrospectivos , Enfermedades Vasculares/complicaciones
17.
Fam Cancer ; 15(4): 571-7, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27017609

RESUMEN

The constitutional MisMatch Repair deficiency (CMMRD) syndrome is one of the inherited cancer predisposition syndromes. More than two-third patients belonging to a CMMRD family are diagnosed mainly in the first decade with brain cancers and/or hematological malignancies. This syndrome is due to bi-allelic germline mutations in genes of the MMR pathway (MLH1, MSH2, MSH6 or PMS2). Our family report begins with the index case presenting initially with a medulloblastoma, which was even the two relapses in complete remission, when she was diagnosed for an AML. She died after bone marrow transplantation from toxicity. The family history was progressively established when her uncle was diagnosed for a colonic cancer and a cousin for a brain tumor. Surprisingly, her father had an atypical sarcoma but her brother also presented a lymphoma followed by a gliomatosis cerebri. A new MLH1 bi-allelic mutation was identified in this family. More than the diagnostic difficulties, this family report illustrates the complexity of the microsatellite instability detection in CMMRD patients, which has to be discussed further to a more accurate diagnosis in the pediatric setting, and address the question of the proper diagnostic tool to use in such genetic background with hypermutated tumors.


Asunto(s)
Neoplasias Encefálicas/genética , Neoplasias Colorrectales/genética , Inestabilidad de Microsatélites , Homólogo 1 de la Proteína MutL/genética , Síndromes Neoplásicos Hereditarios/genética , Neoplasias Encefálicas/etiología , Niño , Neoplasias Colorrectales/etiología , Femenino , Mutación de Línea Germinal , Humanos , Masculino , Síndromes Neoplásicos Hereditarios/etiología , Linaje
18.
J Neurooncol ; 127(2): 345-53, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26732081

RESUMEN

Childhood brain tumors show great histological variability. The goal of this retrospective study was to assess the diagnostic accuracy of multimodal MR imaging (diffusion, perfusion, MR spectroscopy) in the distinction of pediatric brain tumor grades and types. Seventy-six patients (range 1 month to 18 years) with brain tumors underwent multimodal MR imaging. Tumors were categorized by grade (I-IV) and by histological type (A-H). Multivariate statistical analysis was performed to evaluate the diagnostic accuracy of single and combined MR modalities, and of single imaging parameters to distinguish the different groups. The highest diagnostic accuracy for tumor grading was obtained with diffusion-perfusion (73.24%) and for tumor typing with diffusion-perfusion-MR spectroscopy (55.76%). The best diagnostic accuracy was obtained for tumor grading in I and IV and for tumor typing in embryonal tumor and pilocytic astrocytoma. Poor accuracy was seen in other grades and types. ADC and rADC were the best parameters for tumor grading and typing followed by choline level with an intermediate echo time, CBV for grading and Tmax for typing. Multiparametric MR imaging can be accurate in determining tumor grades (primarily grades I and IV) and types (mainly pilocytic astrocytomas and embryonal tumors) in children.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/patología , Imagen de Difusión por Resonancia Magnética/métodos , Adolescente , Astrocitoma/diagnóstico por imagen , Astrocitoma/patología , Neoplasias Encefálicas/clasificación , Niño , Preescolar , Femenino , Estudios de Seguimiento , Glioma/diagnóstico por imagen , Glioma/patología , Humanos , Lactante , Espectroscopía de Resonancia Magnética , Masculino , Clasificación del Tumor , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia
19.
J Pediatr Surg ; 51(1): 179-82, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26592955

RESUMEN

BACKGROUND: Ultrasonography is a well-established efficient diagnostic tool for ileocolic intussusceptions in children. It can also be used to control hydrostatic reduction by saline enemas. This reduction method presents the advantage of avoiding radiations. Parents can even stay with their children during the procedure, which is comforting for both. The purpose of this study was to present our 20 years' experience in intussusception reductions using saline enema under ultrasound control and to assess its efficiency and safety. MATERIAL AND METHODS: This retrospective single center study included patients with ileocolic intussusceptions diagnosed by ultrasound between June 1993 and July 2013. We excluded the data of patients with spontaneous reduction or who underwent primary surgery because of contraindications to hydrostatic reduction (peritonitis, medium or huge abdominal effusion, ischemia on Doppler, bowel perforation). A saline enema was infused into the colon until the reduction was sonographically confirmed. The procedure was repeated if not efficient. Light sedation was practiced in some children. RESULTS: Eighty-tree percent of the reductions were successful with a median of 1 attempt. Reduction success decreased with the number of attempts but was still by 16% after 4 attempts. The early recurrence rates were 14.5%, and 61.2% of those had a successful second complete reduction. Forty-six patients needed surgery (11 of them had a secondary intussusception). Sedation multiplies success by 10. In this period, only one complication is described. CONCLUSION: Ultrasound guided intussusception reduction by saline enema is an efficient and safe procedure. It prevents exposure of a young child to a significant amount of radiation, with similar success rate. We had very low complication rate (1/270 cases or 3‰). The success rate could be increased by standardized procedures including: systematic sedation, trained radiologists, accurate pressure measurement, and number and duration of attempts.


Asunto(s)
Enema/métodos , Enfermedades del Íleon/diagnóstico por imagen , Enfermedades del Íleon/terapia , Intususcepción/diagnóstico por imagen , Intususcepción/terapia , Cloruro de Sodio/administración & dosificación , Enema/efectos adversos , Femenino , Humanos , Lactante , Masculino , Recurrencia , Estudios Retrospectivos , Resultado del Tratamiento , Ultrasonografía
20.
Am J Hum Genet ; 96(4): 666-74, 2015 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-25817018

RESUMEN

We have identified TUBGCP4 variants in individuals with autosomal-recessive microcephaly and chorioretinopathy. Whole-exome sequencing performed on one family with two affected siblings and independently on another family with one affected child revealed compound-heterozygous mutations in TUBGCP4. Subsequent Sanger sequencing was performed on a panel of individuals from 12 French families affected by microcephaly and ophthalmic manifestations, and one other individual was identified with compound-heterozygous mutations in TUBGCP4. One synonymous variant was common to all three families and was shown to induce exon skipping; the other mutations were frameshift mutations and a deletion. TUBGCP4 encodes γ-tubulin complex protein 4, a component belonging to the γ-tubulin ring complex (γ-TuRC) and known to regulate the nucleation and organization of microtubules. Functional analysis of individual fibroblasts disclosed reduced levels of the γ-TuRC, altered nucleation and organization of microtubules, abnormal nuclear shape, and aneuploidy. Moreover, zebrafish treated with morpholinos against tubgcp4 were found to have reduced head volume and eye developmental anomalies with chorioretinal dysplasia. In summary, the identification of TUBGCP4 mutations in individuals with microcephaly and a spectrum of anomalies in eye development, particularly photoreceptor anomalies, provides evidence of an important role for the γ-TuRC in brain and eye development.


Asunto(s)
Enfermedades de la Coroides/genética , Enfermedades Hereditarias del Ojo/genética , Microcefalia/genética , Proteínas Asociadas a Microtúbulos/genética , Microtúbulos/genética , Enfermedades de la Retina/genética , Tubulina (Proteína)/metabolismo , Secuencia de Bases , Exoma/genética , Mutación del Sistema de Lectura/genética , Francia , Componentes del Gen , Humanos , Microtúbulos/metabolismo , Datos de Secuencia Molecular , Linaje , Análisis de Secuencia de ADN
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...