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1.
Eur Radiol ; 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38087063

RESUMO

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.

2.
Am J Hum Genet ; 96(4): 666-74, 2015 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-25817018

RESUMO

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.


Assuntos
Doenças da Coroide/genética , Oftalmopatias Hereditárias/genética , Microcefalia/genética , Proteínas Associadas aos Microtúbulos/genética , Microtúbulos/genética , Doenças Retinianas/genética , Tubulina (Proteína)/metabolismo , Sequência de Bases , Exoma/genética , Mutação da Fase de Leitura/genética , França , Componentes do Gene , Humanos , Microtúbulos/metabolismo , Dados de Sequência Molecular , Linhagem , Análise de Sequência de DNA
3.
Eur Radiol ; 27(5): 1812-1821, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27553925

RESUMO

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.


Assuntos
Doenças dos Ductos Biliares/diagnóstico por imagem , Atresia Biliar/diagnóstico por imagem , Colestase/diagnóstico por imagem , Cistos/diagnóstico por imagem , Vesícula Biliar/diagnóstico por imagem , Síndrome de Heterotaxia/diagnóstico por imagem , Hipertensão Portal/diagnóstico por imagem , Fígado/diagnóstico por imagem , Doenças dos Ductos Biliares/complicações , Atresia Biliar/complicações , Colestase/complicações , Cistos/complicações , Dilatação Patológica/complicações , Dilatação Patológica/diagnóstico por imagem , Feminino , Síndrome de Heterotaxia/complicações , Humanos , Hipertensão Portal/complicações , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos , Sensibilidade e Especificidade , Ultrassonografia
4.
J Neurooncol ; 127(2): 345-53, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26732081

RESUMO

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.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Adolescente , Astrocitoma/diagnóstico por imagem , Astrocitoma/patologia , Neoplasias Encefálicas/classificação , Criança , Pré-Escolar , Feminino , Seguimentos , Glioma/diagnóstico por imagem , Glioma/patologia , Humanos , Lactente , Espectroscopia de Ressonância Magnética , Masculino , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
5.
Med Image Anal ; 97: 103282, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39053168

RESUMO

Fetal brain MRI is becoming an increasingly relevant complement to neurosonography for perinatal diagnosis, allowing fundamental insights into fetal brain development throughout gestation. However, uncontrolled fetal motion and heterogeneity in acquisition protocols lead to data of variable quality, potentially biasing the outcome of subsequent studies. We present FetMRQC, an open-source machine-learning framework for automated image quality assessment and quality control that is robust to domain shifts induced by the heterogeneity of clinical data. FetMRQC extracts an ensemble of quality metrics from unprocessed anatomical MRI and combines them to predict experts' ratings using random forests. We validate our framework on a pioneeringly large and diverse dataset of more than 1600 manually rated fetal brain T2-weighted images from four clinical centers and 13 different scanners. Our study shows that FetMRQC's predictions generalize well to unseen data while being interpretable. FetMRQC is a step towards more robust fetal brain neuroimaging, which has the potential to shed new insights on the developing human brain.

6.
Front Neurol ; 15: 1358741, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38595845

RESUMO

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.

7.
Am J Ophthalmol ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38992673

RESUMO

PURPOSE: To evaluate the effectiveness of baseline screening and follow-up with MRI to detecting trilateral retinoblastoma (TRb) and assessing the risk of TRb development. DESIGN: Prospective multicenter cohort study METHODS: A total of 607 retinoblastoma patients from 2012 through 2022 were included and followed up until 1-9-2023. At each center a neuroradiologist categorized pineal glands on baseline and follow-up scans into four groups: (A) normal, (B) cystic gland, (C) suspicious gland, or (D) TRb. Different follow-up schedules were assigned to each category. Categories (B) and (C) were followed-up with MRI after approximately 3-months and after another 3 months if suspicion remained. On each MRI, they measured the height and width, evaluated the aspect (solid, partly cystic and completely cystic) of the pineal gland and evaluated radiological features suspicious of pineal TRb. The effectiveness of the current TRb screening method was assessed by evaluating its sensitivity and specificity to detect TRb. Determining the TRb incidence was a secondary outcome measure. RESULTS: Heritable retinoblastoma patients had a risk of 3.78% to develop TRb. One out of four pineal TRbs was detected during a follow-up scan and four out of five non-pineal TRbs were detected on the baseline MRI. Screening for pineal TRb had a sensitivity of 25% and specificity of 100%, for non-pineal TRb the sensitivity was 80%. It required 494 follow-up scans to detect one pineal TRb. However, when restricting the follow-up to solely suspicious glands, only 22 scans were required to detect one pineal TRb. CONCLUSION: During extended follow-up after baseline MRI, only one pineal trilateral retinoblastoma was detected in our study. Follow-up after three months should be restricted to patients with a suspicious pineal gland defined as irregularly thickening of the cyst wall (>2mm), fine nodular aspect of the cyst wall or when a solid or cystic gland exceeds the upper 99% prediction interval for size; patients with an unsuspicious cystic gland should not be followed up. Baseline MRI screening was able to detect most non-pineal trilateral retinoblastomas.

8.
Cancers (Basel) ; 16(10)2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38791976

RESUMO

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.

9.
Pediatr Radiol ; 42(7): 886-90, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22006531

RESUMO

We describe fetal septopreoptic holoprosencephaly (HPE) associated with a thick corpus callosum (CC) diagnosed with MRI in a fetus at 31 weeks' gestation. Our report supports a recently published study connecting a thick fetal CC to other brain abnormalities. On diffusion tensor imaging (DTI), the body of the CC contained an abnormal longitudinal bundle, presumed to be a congenital heterotopic cingulum. Prenatal and postmortem brain MRI with DTI, CT, and pathological analyses are described and illustrated.


Assuntos
Corpo Caloso/patologia , Holoprosencefalia/patologia , Imageamento por Ressonância Magnética/métodos , Diagnóstico Pré-Natal/métodos , Displasia Septo-Óptica/patologia , Humanos , Masculino
10.
Skeletal Radiol ; 41(6): 667-75, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21915652

RESUMO

PURPOSE: The goal of this work is to describe the radiological appearance and clinical presentation of subperiosteal iliac hematoma and present a review of the literature. MATERIALS AND METHODS: We retrospectively reviewed the radiological and clinical files of 19 patients (age range: 12-75; mean: 47) who presented with acute or chronic subperiosteal iliac hematomas. Imaging findings and relevant clinical information were recorded. A thorough literature search was performed to find additional cases of this rare condition. RESULTS: Three young patients presented with acute subperiosteal iliac hematoma following a fall. Clinical presentation was characterized by pain and gait disturbance presumed to result from crural nerve compression. Unilateral or bilateral lenticular hematomas deep in the iliacus muscle were demonstrated by CT for all patients while MRI was also available for two of them. In 16 asymptomatic patients, chronic ossified subperiosteal iliac hematomas were incidentally detected by CT. Progressive ossification of acute hematoma was demonstrated at follow-up in two patients. CONCLUSIONS: Subperiosteal iliac hematoma is rare but has typical imaging findings that may present acutely in adolescents or chronically in asymptomatic adults.


Assuntos
Doenças Ósseas/diagnóstico , Hematoma/diagnóstico , Ílio/diagnóstico por imagem , Ílio/patologia , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
11.
Front Neurol ; 13: 827816, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35585848

RESUMO

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.

12.
Sci Rep ; 12(1): 8682, 2022 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-35606398

RESUMO

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.


Assuntos
Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Imagens de Fantasmas
13.
Pediatr Radiol ; 41(3): 389-93, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21076826

RESUMO

We describe ante- and postnatal imaging of a 1-year-old otherwise healthy girl with Raine syndrome. She presented with neonatal respiratory distress related to a pyriform aperture stenosis, which was diagnosed on CT. Signs of chondrodysplasia punctata, sagittal vertebral clefting and intervertebral disc and renal calcifications were also found on imaging. This new case confirms that Raine syndrome is not always lethal. The overlapping imaging signs with chondrodysplasia punctata and the disseminated calcifications give new insights into its pathophysiology.


Assuntos
Anormalidades Múltiplas , Fissura Palatina , Exoftalmia , Microcefalia , Osteosclerose , Anormalidades Múltiplas/diagnóstico por imagem , Fissura Palatina/diagnóstico por imagem , Exoftalmia/diagnóstico por imagem , Feminino , Humanos , Lactente , Microcefalia/diagnóstico por imagem , Osteosclerose/diagnóstico por imagem , Radiografia
14.
Front Pediatr ; 9: 639746, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34447726

RESUMO

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.

15.
Pediatr Radiol ; 40 Suppl 1: S34-7, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20614112

RESUMO

Myositis ossificans (MO) is a rare benign cause of heterotopic bone formation within soft tissue. It most commonly affects adolescents and young adults, typically in the limbs and following trauma. Very few cases have been reported in children. We report here a case of nontraumatic MO occurring in a 10-year-old girl with an uncommon location in the 5th right intercostal space; it was initially misdiagnosed and treated as osteosarcoma. Imaging findings including plain radiographs, CT, MRI, bone scintigraphy and PET-CT are described. This case highlights the central role played by imaging in diagnosis, thus avoiding biopsy that can erroneously suggest osteosarcoma as the diagnosis, as occurred in this case.


Assuntos
Erros de Diagnóstico/prevenção & controle , Miosite Ossificante/diagnóstico por imagem , Costelas/diagnóstico por imagem , Neoplasias Ósseas/diagnóstico por imagem , Criança , Diagnóstico Diferencial , Feminino , Humanos , Osteossarcoma/diagnóstico por imagem , Radiografia
16.
Invest Radiol ; 53(2): 70-79, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28906338

RESUMO

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.


Assuntos
Meios de Contraste/farmacocinética , Aumento da Imagem/métodos , Meglumina/farmacocinética , Compostos Organometálicos/farmacocinética , Encéfalo/diagnóstico por imagem , Meios de Contraste/efeitos adversos , Feminino , Gadolínio , Taxa de Filtração Glomerular , Humanos , Lactente , Recém-Nascido , Injeções Intravenosas , Imageamento por Ressonância Magnética/métodos , Masculino , Meglumina/efeitos adversos , Compostos Organometálicos/efeitos adversos , Estudos Prospectivos , Coluna Vertebral/diagnóstico por imagem
17.
Presse Med ; 36(3 Pt 2): 492-5, 2007 Mar.
Artigo em Francês | MEDLINE | ID: mdl-17336858

RESUMO

MRI uses the magnetic properties of the hydrogen atoms present in the human body. It presents no risks as long as the contraindications (pacemaker, metal fragment in the eye, pregnancy less than 3 months) are complied with. MRI is the reference imaging method for exploration of the brain. The contrast of these images depends on the type of sequence used. More specific sequences (diffusio-weighted, gradient echo) and gadolinium injection can be added to the basic sequences (T1, T2, Flair).


Assuntos
Encefalopatias/diagnóstico , Imageamento por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética/métodos
18.
Parkinsonism Relat Disord ; 39: 4-16, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28256436

RESUMO

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.


Assuntos
Blefarospasmo , Doença de Parkinson Secundária , Transtornos Parkinsonianos , Blefarospasmo/complicações , Blefarospasmo/diagnóstico , Blefarospasmo/genética , Encéfalo/diagnóstico por imagem , Bases de Dados Bibliográficas/estatística & dados numéricos , Globo Pálido , Humanos , Imageamento por Ressonância Magnética , Doença de Parkinson Secundária/complicações , Doença de Parkinson Secundária/diagnóstico , Doença de Parkinson Secundária/genética , Transtornos Parkinsonianos/complicações , Transtornos Parkinsonianos/diagnóstico , Transtornos Parkinsonianos/genética
19.
Eur J Pediatr Surg ; 27(2): 177-180, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27065355

RESUMO

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.


Assuntos
Diafragma/crescimento & desenvolvimento , Hérnias Diafragmáticas Congênitas/terapia , Tomografia Computadorizada por Raios X/métodos , Adolescente , Diafragma/anatomia & histologia , Diafragma/diagnóstico por imagem , Humanos , Lactente , Próteses e Implantes/efeitos adversos , Estudos Retrospectivos , Estatísticas não Paramétricas
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