Validation of an automatic tool for the rapid measurement of brain atrophy and white matter hyperintensity: QyScore®.

OBJECTIVES: QyScore® is an imaging analysis tool certified in Europe (CE marked) and the US (FDA cleared) for the automatic volumetry of grey and white matter (GM and WM respectively), hippocampus (HP), amygdala (AM), and white matter hyperintensity (WMH). Here we compare QyScore® performances with the consensus of expert neuroradiologists. METHODS: Dice similarity coefficient (DSC) and the relative volume difference (RVD) for GM, WM volumes were calculated on 50 3DT1 images. DSC and the F1 metrics were calculated for WMH on 130 3DT1 and FLAIR images. For each index, we identified thresholds of reliability based on current literature review results. We hypothesized that DSC/F1 scores obtained using QyScore® markers would be higher than the threshold. In contrast, RVD scores would be lower. Regression analysis and Bland-Altman plots were obtained to evaluate QyScore® performance in comparison to the consensus of three expert neuroradiologists. RESULTS: The lower bound of the DSC/F1 confidence intervals was higher than the threshold for the GM, WM, HP, AM, and WMH, and the higher bounds of the RVD confidence interval were below the threshold for the WM, GM, HP, and AM. QyScore®, compared with the consensus of three expert neuroradiologists, provides reliable performance for the automatic segmentation of the GM and WM volumes, and HP and AM volumes, as well as WMH volumes. CONCLUSIONS: QyScore® represents a reliable medical device in comparison with the consensus of expert neuroradiologists. Therefore, QyScore® could be implemented in clinical trials and clinical routine to support the diagnosis and longitudinal monitoring of neurological diseases. KEY POINTS: • QyScore® provides reliable automatic segmentation of brain structures in comparison with the consensus of three expert neuroradiologists. • QyScore® automatic segmentation could be performed on MRI images using different vendors and protocols of acquisition. In addition, the fast segmentation process saves time over manual and semi-automatic methods. • QyScore® could be implemented in clinical trials and clinical routine to support the diagnosis and longitudinal monitoring of neurological diseases.

The coeruleus/subcoeruleus complex in rapid eye movement sleep behaviour disorders in Parkinson's disease.

In Parkinson's disease, rapid eye movement sleep behaviour disorder is an early non-dopaminergic syndrome with nocturnal violence and increased muscle tone during rapid eye movement sleep that can precede Parkinsonism by several years. The neuronal origin of rapid eye movement sleep behaviour disorder in Parkinson's disease is not precisely known; however, the locus subcoeruleus in the brainstem has been implicated as this structure blocks muscle tone during normal rapid eye movement sleep in animal models and can be damaged in Parkinson's disease. Here, we studied the integrity of the locus coeruleus/subcoeruleus complex in patients with Parkinson's disease using combined neuromelanin-sensitive, structural and diffusion magnetic resonance imaging approaches. We compared 24 patients with Parkinson's disease and rapid eye movement sleep behaviour disorder, 12 patients without rapid eye movement sleep behaviour disorder and 19 age- and gender-matched healthy volunteers. All subjects underwent clinical examination and characterization of rapid eye movement sleep using video-polysomnography and multimodal imaging at 3 T. Using neuromelanin-sensitive imaging, reduced signal intensity was evident in the locus coeruleus/subcoeruleus area in patients with Parkinson's disease that was more marked in patients with than those without rapid eye movement sleep behaviour disorder. Reduced signal intensity correlated with the percentage of abnormally increased muscle tone during rapid eye movement sleep. The results confirmed that this complex is affected in Parkinson's disease and showed a gradual relationship between damage to this structure, presumably the locus subcoeruleus, and abnormal muscle tone during rapid eye movement sleep, which is the cardinal marker of rapid eye movement sleep behaviour disorder. In longitudinal studies, the technique may also provide early markers of non-dopaminergic Parkinson's disease pathology to predict the occurrence of Parkinson's disease.

Magnetic resonance imaging of the substantia nigra in Parkinson's disease.

Until recently, conventional magnetic resonance imaging (MRI) was most often negative in Parkinson's disease or showed nonspecific findings. Recent developments in structural MRI, including relaxometry, magnetization transfer, and neuromelanin imaging, have demonstrated improved contrast and enabled more accurate visualization of deep brain nuclei, in particular, the substantia nigra. Meanwhile, diffusion imaging has provided useful biomarkers of substantia nigra degeneration, showing reduced anisotropy and anatomical connectivity with the striatum and thalamus. These advances in structural imaging are complemented by findings of magnetic resonance spectroscopy on brain metabolism and resting-state functional MRI on functional connectivity. This article presents an overview of these new structural, metabolic, and resting-state functional MRI techniques and their implications for Parkinson's disease. The techniques are reviewed in the context of their potential for better understanding the disease in terms of diagnosis and pathophysiology and as biomarkers of its progression.

Automatic segmentation of white matter hyperintensities: validation and comparison with state-of-the-art methods on both Multiple Sclerosis and elderly subjects.

Different types of white matter hyperintensities (WMH) can be observed through MRI in the brain and spinal cord, especially Multiple Sclerosis (MS) lesions for patients suffering from MS and age-related WMH for subjects with cognitive disorders and/or elderly people. To better diagnose and monitor the disease progression, the quantitative evaluation of WMH load has proven to be useful for clinical routine and trials. Since manual delineation for WMH segmentation is highly time-consuming and suffers from intra and inter observer variability, several methods have been proposed to automatically segment either MS lesions or age-related WMH, but none is validated on both WMH types. Here, we aim at proposing the White matter Hyperintensities Automatic Segmentation Algorithm adapted to 3D T2-FLAIR datasets (WHASA-3D), a fast and robust automatic segmentation tool designed to be implemented in clinical practice for the detection of both MS lesions and age-related WMH in the brain, using both 3D T1-weighted and T2-FLAIR images. In order to increase its robustness for MS lesions, WHASA-3D expands the original WHASA method, which relies on the coupling of non-linear diffusion framework and watershed parcellation, where regions considered as WMH are selected based on intensity and location characteristics, and finally refined with geodesic dilation. The previous validation was performed on 2D T2-FLAIR and subjects with cognitive disorders and elderly subjects. 60 subjects from a heterogeneous database of dementia patients, multiple sclerosis patients and elderly subjects with multiple MRI scanners and a wide range of lesion loads were used to evaluate WHASA and WHASA-3D through volume and spatial agreement in comparison with consensus reference segmentations. In addition, a direct comparison on the MS database with six available supervised and unsupervised state-of-the-art WMH segmentation methods (LST-LGA and LPA, Lesion-TOADS, lesionBrain, BIANCA and nicMSlesions) with default and optimised settings (when feasible) was conducted. WHASA-3D confirmed an improved performance with respect to WHASA, achieving a better spatial overlap (Dice) (0.67 vs 0.63), a reduced absolute volume error (AVE) (3.11 vs 6.2 mL) and an increased volume agreement (intraclass correlation coefficient, ICC) (0.96 vs 0.78). Compared to available state-of-the-art algorithms on the MS database, WHASA-3D outperformed both unsupervised and supervised methods when used with their default settings, showing the highest volume agreement (ICC = 0.95) as well as the highest average Dice (0.58). Optimising and/or retraining LST-LGA, BIANCA and nicMSlesions, using a subset of the MS database as training set, resulted in improved performances on the remaining testing set (average Dice: LST-LGA default/optimized = 0.41/0.51, BIANCA default/optimized = 0.22/0.39, nicMSlesions default/optimized = 0.17/0.63, WHASA-3D = 0.58). Evaluation and comparison results suggest that WHASA-3D is a reliable and easy-to-use method for the automated segmentation of white matter hyperintensities, for both MS lesions and age-related WMH. Further validation on larger datasets would be useful to confirm these first findings.

Diet and nutritional status of children with food allergies.

The aim of the present study was to assess the food intakes and nutritional status of children with food allergies following an elimination diet. We conducted a cross sectional study including 96 children (mean age 4.7 ± 2.5 years) with food allergies and 95 paired controls (mean age 4.7 ± 2.7 years) without food allergies. Nutritional status was assessed using measurements of weight and height and Z scores for weight-for-age, height-for-age and weight-for-height. Nutrient intakes assessment was based on a 3-day diet record. Children with food allergies had weight-for-age and height-for-age Z scores lower than controls (0.1 versus 0.6 and 0.2 versus 0.8 respectively). Children with 3 or more food allergies were smaller than those with 2 or less food allergies (p = 0.04). A total of 62 children with food allergies and 52 controls completed usable diet records. Energy, protein and calcium intakes were similar in the two groups. Children with food allergies were smaller for their age than controls even when they received similar nutrient intakes. Nutritional evaluation is essential for the follow up of children with food allergies.

Spirometry in 3-5-year-old children with asthma.

Spirometry with incentive games was applied to 207 2-5-year-old preschool children (PSC) with asthma in order to refine the quality-control criteria proposed by Aurora et al. (Am J Respir Crit Care Med 2004;169:1152-159). The data set in our study was much larger compared to that in Aurora et al. (Am J Respir Crit Care Med 2004;169:1152-159), where 42 children with cystic fibrosis and 37 healthy control were studied. At least two acceptable maneuvers were obtained in 178 (86%) children. Data were focused on 3-5-year-old children (n = 171). The proportion of children achieving a larger number of thresholds for each quality-control criterion (backward-extrapolated volume (Vbe), Vbe in percent of forced vital capacity (FVC, Vbe/FVC), time-to-peak expiratory flow (time-to-PEF), and difference (Delta) between the two FVCs (DeltaFVC), forced expiratory volume in 1 sec (DeltaFEV(1)), and forced expiratory volume in 0.5 sec (DeltaFEV(0.5)) from the two "best" curves) was calculated, and cumulative plots were obtained. The optimal threshold was determined for all ages by derivative function of rate of success-threshold curves, close to the inflexion point. The following thresholds were defined for acceptability: Vbe

Crianças em situaçäo de rua de Porto Alegre: um estudo descritivo / Street children in Porto Alegre: a descriptive study

Este artigo tem por objetivo descrever uma populaçäo de crianças em situaçäo de rua do centro da cidade de Porto Alegre. Para tanto, foi utilizada uma entrevista estruturada, aplicada a uma amostra de vinte crianças (20) - doze meninos e oito meninas, com idades entre seis e doze anos. Através da entrevista, buscou-se investigar as relaçöes da criança com a familia, com o trabalho, com a escola e com a forma como ocupa seu tempo. Os autores enfatizam a importância de estudos descritivos, que priorizem caracterizar esta populaçäo, a fim de que programas interventivos tenham como base aspectos fidedignos da mesma, tornando-se, assim mais eficazes

Atividades cotidianas de crianças em situaçäo de rua / Daily activities of street children

Este estudo apresenta resultados de uma pesquisa descritiva da observaçäo de atividades cotidianas de vinte crianças em situaçäo de rua da área central de Porto Alegre, Brasil. Os dados foram coletados através de uma metodologia observacional elaborada especificamente para utilizaçäo em pesquisas no contexto da rua, associada a uma entrevista estruturada para obtençäo de dados bio-sócio-demográficos. Os resultados revelam que as crianças utilizam o espaço da rua para diversas atividades, incluindo tarefas que garantem a subsistência pessoal e, às vezes, da família. Foram também observadas brincadeiras solitárias ou em grupo, demonstrando que embora estejam em atividade de trabalho, continuam sendo crianças em desenvolvimento. A discussäo dos dados, baseada na Teoria dos Sistemas Ecológicos, salienta a importância de estudos que descrevam os aspectos saudáveis que meninos e meninas em situaçäo de rua podem apresentar neste ambiente. Alternativas de intervençäo nesta situaçäo devem enfatizar a participaçäo comunitária e da sociedade civil na efetivaçäo de propostas de apoio sócio-afetivo para estas crianças e suas famílias.

A construçäo de uma metodologia observacional para o estudo de crianças em situaçäo de rua: criando um manual de codificaçäo de atividades cotidianas / The construction of an observational method of studing children in the context of the street: creating a manual to codify daily activities

Este estudo teve por objetivo descrever uma metodologia criada para a observaçäo de crianças em situaçäo de rua em seu ambiente natural. Questöes sobre o desenvolvimento dessas crianças, sobre a utilizaçäo e significado do espaço da rua e sobre os aspectos metodológicos foram relevantes para a realizaçäo deste tipo de estudo. Os resultados encontram-se condensados em um manual criado especialmente para a codificaçäo das atividades cotidianas apresentadas pelas crianças em situaçäo de rua. A discussäo enfatiza a importância da realizaçäo de estudos observacionais exploratórios e descritivos para avaliar o processo de criaçäo de metodologias específicas para entender e analisar o desenvolvimento humano em situaçöes de risco. A aplicabilidade deste método é discutida como conhecimento produzido pela Psicologia do Desenvolvimento

Brinquedo, trabalho, espaço e companhia de atividades lúdicas no relato de crianças em situação de rua / Work, space and companionship in playing according to street children reports

Este artigo apresenta resultados de um estudo exploratório com vinte crianças em situação de rua de Porto Alegre. São descritos seus dados bio-sócio-demográfico e suas opiniões sobre brinquedo, trabalho, espaços e companhias de brincadeira, coletados através de uma entrevista estruturada e do jogo de sentenças incompletas sobre brinquedo. Os resultados mostram que: a) a maioria destas crianças tem contato cotidiano com a família, b) a experiência escolar e o trabalho são atividades freqüentes, c) o brincar esta relacionado a sentimentos de alegria e prazer, d) as ruas próximas de suas casas são o espaço para a realização de atividades lúdicas, e) as companhias de brincadeiras são outras crianças, f) os brinquedos industrializados são os mais desejados e a escolha é influenciada pelo gênero das crianças. Os dados são discutidos na perspectiva da teoria dos sistemas ecológicos, abrangendo desde questões familiares e escolares até a influência da cultura e dos estereótipos no cotidiano