Intraobserver and interobserver variability of ascending aorta diameter as assessed with ECG-gated MDCT: automatic versus manual measurements

Purpose: Recently morphometric measurements of the ascending aorta have been done with ECG-gated MDCT to help the development of future endovascular therapies (TCT) [1]. However, the variability of these measurements remains unknown. It will be interesting to know the impact of CAD (computer aided diagnosis) with automated segmentation of the vessel and automatic measurements of diameter on the management of ascending aorta aneurysms. Methods and Materials: Thirty patients referred for ECG-gated CT thoracic angiography (64-row CT scanner) were evaluated. Measurements of the maximum and minimum ascending aorta diameters were obtained automatically with a commercially available CAD and semi-manually by two observers separately. The CAD algorithms segment the iv-enhanced lumen of the ascending aorta into perpendicular planes along the centreline. The CAD then determines the largest and the smallest diameters. Both observers repeated the automatic measurements and the semimanual measurements during a different session at least one month after the first measurements. The Bland and Altman method was used to study the inter/intraobserver variability. A Wilcoxon signed-rank test was also used to analyse differences between observers. Results: Interobserver variability for semi-manual measurements between the first and second observers was between 1.2 to 1.0 mm for maximal and minimal diameter, respectively. Intraobserver variability of each observer ranged from 0.8 to 1.2 mm, the lowest variability being produced by the more experienced observer. CAD variability could be as low as 0.3 mm, showing that it can perform better than human observers. However, when used in nonoptimal conditions (streak artefacts from contrast in the superior vena cava or weak lumen enhancement), CAD has a variability that can be as high as 0.9 mm, reaching variability of semi-manual measurements. Furthermore, there were significant differences between both observers for maximal and minimal diameter measurements (p<0.001). There was also a significant difference between the first observer and CAD for maximal diameter measurements with the former underestimating the diameter compared to the latter (p<0.001). As for minimal diameters, they were higher when measured by the second observer than when measured by CAD (p<0.001). Neither the difference of mean minimal diameter between the first observer and CAD nor the difference of mean maximal diameter between the second observer and CAD was significant (p=0.20 and 0.06, respectively). Conclusion: CAD algorithms can lessen the variability of diameter measurements in the follow-up of ascending aorta aneurysms. Nevertheless, in non-optimal conditions, it may be necessary to correct manually the measurements. Improvements of the algorithms will help to avoid such a situation.

Variability of ascending aorta diameter measurements as assessed with electrocardiography-gated multidetector computerized tomography and computer assisted diagnosis software.

Recently, morphometric measurements of the ascending aorta have been done with ECG-gated multidector computerized tomography (MDCT) to help the development of future novel transcatheter therapies (TCT); nevertheless, the variability of such measurements remains unknown. Thirty patients referred for ECG-gated CT thoracic angiography were evaluated. Continuous reformations of the ascending aorta, perpendicular to the centerline, were obtained automatically with a commercially available computer aided diagnosis (CAD). Then measurements of the maximal diameter were done with the CAD and manually by two observers (separately). Measurements were repeated one month later. The Bland-Altman method, Spearman coefficients, and a Wilcoxon signed-rank test were used to evaluate the variability, the correlation, and the differences between observers. The interobserver variability for maximal diameter between the two observers was up to 1.2 mm with limits of agreement [-1.5, +0.9] mm; whereas the intraobserver limits were [-1.2, +1.0] mm for the first observer and [-0.8, +0.8] mm for the second observer. The intraobserver CAD variability was 0.8 mm. The correlation was good between observers and the CAD (0.980-0.986); however, significant differences do exist (P<0.001). The maximum variability observed was 1.2 mm and should be considered in reports of measurements of the ascending aorta. The CAD is as reproducible as an experienced reader.

Prospective comparison of MR enteroclysis with multidetector spiral-CT enteroclysis: interobserver agreement and sensitivity by means of "sign-by-sign" correlation.

Our objective was a prospective comparison of MR enteroclysis (MRE) with multidetector spiral-CT enteroclysis (MSCTE). Fifty patients with various suspected small bowel diseases were investigated by MSCTE and MRE. The MSCTE was performed using slices of 2.5 mm, immediately followed by MRE, obtaining T1- and T2-weighted sequences, including gadolinium-enhanced acquisition with fat saturation. Three radiologists independently evaluated MSCTE and MRE searching for 12 pathological signs. Interobserver agreement was calculated. Sensitivities and specificities resulted from comparison with pathological results ( n=29) and patient's clinical evolution ( n=21). Most pathological signs, such as bowel wall thickening (BWT), bowel wall enhancement (BWE) and lymphadenopathy (ADP), showed better interobserver agreement on MSCTE than on MRE (BWT: 0.65 vs 0.48; BWE: 0.51 vs 0.37; ADP: 0.52 vs 0.15). Sensitivity of MSCTE was higher than that of MRE in detecting BWT (88.9 vs 60%), BWE (78.6 vs 55.5%) and ADP (63.8 vs 14.3%). Wilcoxon signed-rank test revealed significantly better sensitivity of MSCTE than that of MRE for each observer ( p=0.028, p=0.046, p=0.028, respectively). Taking the given study design into account, MSCTE provides better sensitivity in detecting lesions of the small bowel than MRE, with higher interobserver agreement.

Interobserver and intraobserver variability of the apparent diffusion coefficient in treated malignant hepatic lesions on a 3.0T machine: measurements in the whole lesion versus in the area with the most restricted diffusion.

PURPOSE: To assess the inter/intraobserver variability of apparent diffusion coefficient (ADC) measurements in treated hepatic lesions and to compare ADC measurements in the whole lesion and in the area with the most restricted diffusion (MRDA). MATERIALS AND METHODS: Twenty-five patients with treated malignant liver lesions were examined on a 3.0T machine. After agreeing on the best ADC image, two readers independently measured the ADC values in the whole lesion and in the MRDA. These measurements were repeated 1 month later. The Bland-Altman method, Spearman correlation coefficients, and the Wilcoxon signed-rank test were used to evaluate the measurements. RESULTS: Interobserver variability for ADC measurements in the whole lesion and in the MRDA was 0.17 x 10(-3) mm(2)/s [-0.17, +0.17] and 0.43 x 10(-3) mm(2)/s [-0.45, +0.41], respectively. Intraobserver limits of agreement could be as low as [-0.10, +0.12] 10(-3) mm(2)/s and [-0.20, +0.33] 10(-3) mm(2)/s for measurements in the whole lesion and in the MRDA, respectively. CONCLUSION: A limited variability in ADC measurements does exist, and it should be considered when interpreting ADC values of hepatic malignancies. This is especially true for the measurements of the minimal ADC.

Spirometric abnormalities in patients with Fabry disease and effect of enzyme replacement therapy

Aim: Fabry disease is an X-linked genetic disorder due to deficiency of the lysosomal enzyme a-galactosidase A, which leads to the accumulation of neutral glycosphingolipids within the lysosomes of almost all tissues. Clinical manifestations usually include acroparaesthesia, renal insufficiency and cardiomyopathy. Recently, pulmonary manifestations consisting of progressive obstructive airway disease have been reported. The aim of this study was to analyse the cross-sectional prevalence of airflow obstruction in a Swiss cohort of patients, and in selected cases, to evaluate the impact of enzyme replacement therapy (ERT) with agalsidase alfa (ReplagalTM; TKT - 5S). Methods: Forty-four patients (27 men, 17 women) were included in the study and received pulmonary function testing. Fifteen patients underwent spirometry after ERT. Results: Twelve patients (nine men) had chronic obstructive pulmonary disease according to the Global Obstructive Lung Disease (GOLD) initiative criteria: forced expiratory volume (FEV1)/forced vital capacity (FVC) 50.7), but only one was an active smoker and one a previous smoker. FEV1/ FVC as percentage predicted was weakly correlated with age (r=0.42, p=0.005, calculated by Pearson product-moment correlation), demonstrating that airway obstruction occurs in the late stages of the disease. Median FEV1 in patients with obstruction was 67% of predicted (range, 45-90%). Reversibility of FEV1 after b2-agonist inhalation never exceeded 8% of predicted. Diffusing capacity of the lung for carbon monoxide (DLCO) was measured in 13 individuals with a median of 88% of predicted (range, 39-125%). After 15+9 months of ERT, spirometry measurements were recorded in 15 patients. Decline in FEV1 was -2+5% of predicted. (p40.05, measured by the Wilcoxon signed-rank test). Median change in DLCO was -10% of predicted (-40 to +25%, p40.05). High resolution computed tomography scans demonstrated a moderate thickening of the bronchial wall in affected individuals, without evidence of emphysema. Conclusion: We conclude that Fabry disease can be complicated by significant airway obstruction, particularly in patients in the advanced stages of the disease, and that in the period studied, ERT had no demonstrable impact on pulmonary function.

Interhemispheric distribution of Alzheimer disease and vascular pathology in brain aging

BACKGROUND AND PURPOSE: Most of the neuropathological studies in brain aging were based on the assumption of a symmetrical right-left hemisphere distribution of both Alzheimer disease and vascular pathology. To explore the impact of asymmetrical lesion formation on cognition, we performed a clinicopathological analysis of 153 cases with mixed pathology except macroinfarcts. METHODS: Cognitive status was assessed prospectively using the Clinical Dementia Rating scale; neuropathological evaluation included assessment of Braak neurofibrillary tangle and Ass deposition staging, microvascular pathology, and lacunes. The right-left hemisphere differences in neuropathological scores were evaluated using the Wilcoxon signed rank test. The relationship between the interhemispheric distribution of lesions and Clinical Dementia Rating scores was assessed using ordered logistic regression. RESULTS: Unlike Braak neurofibrillary tangle and Ass deposition staging, vascular scores were significantly higher in the left hemisphere for all Clinical Dementia Rating scores. A negative relationship was found between Braak neurofibrillary tangle, but not Ass staging, and vascular scores in cases with moderate to severe dementia. In both hemispheres, Braak neurofibrillary tangle staging was the main determinant of cognitive decline followed by vascular scores and Ass deposition staging. The concomitant predominance of Alzheimer disease and vascular pathology in the right hemisphere was associated with significantly higher Clinical Dementia Rating scores. CONCLUSIONS: Our data show that the cognitive impact of Alzheimer disease and vascular lesions in mixed cases may be assessed unilaterally without major information loss. However, interhemispheric differences and, in particular, increased vascular and Alzheimer disease burden in the right hemisphere may increase the risk for dementia in this group.

A multicentre, retrospective case-control study assessing the role of trabecular bone score (TBS) in menopausal Caucasian women with low areal bone mineral density (BMDa): Analysing the odds of vertebral fracture.

INTRODUCTION: The trabecular bone score (TBS) is a new parameter that is determined from grey level analysis of DXA images. It relies on the mean thickness and volume fraction of trabecular bone microarchitecture. This was a preliminary case-control study to evaluate the potential diagnostic value of TBS, both alone and combined with bone mineral density (BMDa), in the assessment of vertebral fracture. METHODS: Out of a subject pool of 441 Caucasian, postmenopausal women between the ages of 50 and 80 years, we identified 42 women with osteoporosis-related vertebral fractures, and compared them with 126 age-matched women without any fractures (1 case: 3 controls). Primary outcomes were BMDa and TBS. Inter-group comparisons were undertaken using Student's t-tests and Wilcoxon signed ranks tests for parametric and non-parametric data, respectively. Odds ratios for vertebral fracture were calculated for each incremental one standard deviation decrease in BMDa and TBS, and areas under the receiver operating curve (AUC) calculated and sensitivity analysis were conducted to compare BMDa alone, TBS alone, and the combination of BMDa and TBS. Subgroup analyses were performed specifically for women with osteopenia, and for women with T-score-defined osteoporosis. RESULTS: Across all subjects (n=42, 126) weight and body mass index were greater and BMDa and TBS both less in women with fractures. The odds of vertebral fracture were 3.20 (95% CI, 2.01-5.08) for each incremental decrease in TBS, 1.95 (1.34-2.84) for BMDa, and 3.62 (2.32-5.65) for BMDa + TBS combined. The AUC was greater for TBS than for BMDa (0.746 vs. 0.662, p=0.011). At iso-specificity (61.9%) or iso-sensitivity (61.9%) for both BMDa and TBS, TBS + BMDa sensitivity or specificity was 19.1% or 16.7% greater than for either BMDa or TBS alone. Among subjects with osteoporosis (n=11, 40) both BMDa (p=0.0008) and TBS (p=0.0001) were lower in subjects with fractures, and both OR and AUC (p=0.013) for BMDa + TBS were greater than for BMDa alone (OR=4.04 [2.35-6.92] vs. 2.43 [1.49-3.95]; AUC=0.835 [0.755-0.897] vs. 0.718 [0.627-0.797], p=0.013). Among subjects with osteopenia, TBS was lower in women with fractures (p=0.0296), but BMDa was not (p=0.75). Similarly, the OR for TBS was statistically greater than 1.00 (2.82, 1.27-6.26), but not for BMDa (1.12, 0.56-2.22), as was the AUC (p=0.035), but there was no statistical difference in specificity (p=0.357) or sensitivity (p=0.678). CONCLUSIONS: The trabecular bone score warrants further study as to whether it has any clinical application in osteoporosis detection and the evaluation of fracture risk.

Combined Serum Creatinine and Cystatin C Schwartz Formula Predicts Kidney Function Better than the Combined CKD-EPI Formula in Children.

Background: The combined serum creatinine (SCreat) and cystatin C (CysC) CKD-EPI formula constitutes a new advance for glomerular filtration rate (GFR) estimation in adults. Using inulin clearances (iGFRs), the revised SCreat and the combined Schwartz formulas, this study aims to evaluate the applicability of the combined CKD-EPI formula in children. Method: 201 iGFRs for 201 children were analyzed and divided by chronic kidney disease (CKD) stages (iGFRs ≥90 ml/min/1.73 m(2), 90 > iGFRs > 60, and iGFRs ≤59), and by age groups (<10, 10-15, and >15 years). Medians with 95% confidence intervals of bias, precision, and accuracies within 30% of the iGFRs, for all three formulas, were compared using the Wilcoxon signed-rank test. Results: For the entire cohort and for all CKD and age groups, medians of bias for the CKD-EPI formula were significantly higher (p < 0.001) and precision was significantly lower than the solely SCreat and the combined SCreat and CysC Schwartz formulas. We also found that using the CKD-EPI formula, bias decreased and accuracy increased while the child age group increased, with a better formula performance above 15 years of age. However, the CKD-EPI formula accuracy is 58% compared to 93 and 92% for the SCreat and combined Schwartz formulas in this adolescent group. Conclusions: The performance of the combined CKD-EPI formula improves in adolescence compared with younger ages. Nevertheless, the CKD-EPI formula performs more poorly than the SCreat and the combined Schwartz formula in pediatric population. © 2013 S. Karger AG, Basel.

Retrospektive Analyse der Mixantron-Behandlung bei Multipler Sklerose von Juli 2000 bis Juni 2007

Résumé :Introduction : La mitoxantrone est un anthracénédione cytostatique aux ef¬fets immunosuppresseurs et -modulateurs qui est administré entre autre dans les évolutions graves de la sclérose en plaques (SEP). Peu d'études concernant l'efficacité et la tolérance de la mitoxantrone ont été publiées. Un travail de re¬cherche statistique s'imposait en raison du nombre de patients souffrant de SEP traités par ce médicament dans le service de neurologie de l'hôpital cantonal d'Aarau.Méthode : Au total, 66 patients souffrant de SEP ont été traités par la mi¬toxantrone dans la période 07/2000-06/2007. 48 d'entre eux avaient reçu préa¬lablement une autre substance modifiant l'évolution de la maladie (« prétrai¬tement » : interféron bêta-la/b, glatirameracétate, azathioprine). Dans cette étude rétrospective, nous avons comparé l'effet de la mitoxantrone par rapport au prétraitement mentionné ci-dessus. Les paramètres appliqués concernaient l'évolution de l'expanded disability status scale (EDSS) et le nombre annuel de poussées pendant la durée du traitement. Une influence du type de SEP, de l'âge au début du traitement par la mitoxantrone, du sexe, de la durée de la théra¬pie et de la maladie ainsi que de la dose cumulative de la mitoxantrone a été recherchée. Nous avons également discuté des éventuels effets indésirables surve¬nus. Nous n'avons pas différencié les substances du prétraitement, étant donné qu'elles avaient été appliquées dans des combinaisons multiples. L'évaluation sta¬tistique a été effectuée en respectant les indications du test de Mann-Whitney ainsi que du Wilcoxon signed-rank test.Résultats : En moyenne, l'EDSS s'est stabilisée (-0,05/année chez tous les 66 patients) tandis que la maladie avait progressé de 0,32/année sous le pré¬traitement (la différence est significative avec p=0,0004 au Wilcoxon signed- rank test bilatéral). Sous le prétraitement, les patients avaient subi en moyenne 1,72 poussées par année, sous la mitoxantrone 0,26 (différence significative avec p<0,0001). La thérapie a dû être arrêtée à cause d'effets indésirables chez quatre patients sous la mitoxantrone (deux avec une granulocytopénie, deux avec une diminution de la fraction d'éjection cardiaque).Discussion : La mitoxantrone s'est avéré une substance particulièrement ef¬ficace même dans les situations dans lesquelles le décours de la maladie n'a pas pu être influencé par d'autres médicaments. Ses effets indésirables doivent être pondérés par rapport à la progression de la maladie et aux effets indési¬rables des autres substances. Les schémas d'application varient beaucoup dans la littérature et doivent être mieux définis.Zusammenfassung :Einleitung: Mitoxantron ist ein zytostatisches Anthracenedion mit immunsup- pressiven und -modulatorischen Eigenschaften, das unter anderem bei schwe¬ren Verläufen der Multiplen Sklerose eingesetzt wird. Bisher befassten sich nur wenige randomisierte und plazebokontrollierte Studien mit Wirksamkeit und Tolerabilität des Medikamentes.Methoden: 66 MS-Patienten der neurologischen Klinik des Kantonsspitals Aar- au wurden zwischen Juli 2000 und Juni 2007 mit Mitoxantron behandelt. 48 davon erhielten zuvor eine MS-spezifische Behandlung mit Interferon ß-1 a oder b, Glatirameracetat oder Azathioprin. Anhand der Veränderung der Expanded Disability Status Scale (EDSS) und der jährlichen Schubrate und mit Hilfe von MRI-Aufnahmen zeichneten wir retrospektiv die Wirksamkeit der Behandlung nach und stellten sie in Beziehung zu einer eventuell erfolgten Vorbehandlung. Des weiteren wurde die Effektivität in Verhältnis zu den Faktoren Verlaufsform, Alter bei Behandlungsbeginn, Behandlungszeit sowie weiteren Parametern ge¬bracht. Wir verglichen die Wirkung von Mitoxantron bei den noch laufenden Behandlungen mit der bei den bereits abgeschlossenen und wir diskutierten die Veränderung von MRI-Aufnahmen des ZNS unter der Therapie mit Mitoxan¬tron. Nebenwirkungen wurden erwähnt.Resultate: Im Durchschnitt wurde der EDSS-Wert stabilisiert (-0, 05/Jahr bei allen 66 Patienten), während die Krankheit unter der verlaufsmodifizierenden Vorbehandlung um durchschnittlich 0,32/Jahr fortschritt (Unterschied signifi¬kant mit p=0,0004 im zweiseitigen Wilcoxon signed-rank test). Die Schubrate betrug 0,26 unter Mitoxantron gegenüber 1,72/Jahr unter Vorbehandlung (Un¬terschied signifikant mit p<0,0001). Bei vier Patienten musste die Therapie auf¬grund von Nebenwirkungen abgebrochen werden (zweimal Granulozytopenie, zweimal verminderte kardiale Auswurffraktion).Diskussion: Mitoxantron ist offensichtlich selbst dann eine äusserst effektive verlaufsmodifizierende Substanz, wenn die Krankheit durch andere Medikamen¬te nicht zu beeinflussen ist. Die Risiken des Medikamentes müssen gegen das Krankheitsfortschreiten und die Nachteile anderer verlaufsmodifizierender Sub¬stanzen abgewogen werden. Die Anwendungsalgorithmen für Mitoxantron vari¬ieren in der Literatur sehr und müssen besser definiert werden.

Neural detection of complex sound sequences in the absence of consciousness.

The neural response to a violation of sequences of identical sounds is a typical example of the brain's sensitivity to auditory regularities. Previous literature interprets this effect as a pre-attentive and unconscious processing of sensory stimuli. By contrast, a violation to auditory global regularities, i.e. based on repeating groups of sounds, is typically detectable when subjects can consciously perceive them. Here, we challenge the notion that global detection implies consciousness by testing the neural response to global violations in a group of 24 patients with post-anoxic coma (three females, age range 45-87 years), treated with mild therapeutic hypothermia and sedation. By applying a decoding analysis to electroencephalographic responses to standard versus deviant sound sequences, we found above-chance decoding performance in 10 of 24 patients (Wilcoxon signed-rank test, P < 0.001), despite five of them being mildly hypothermic, sedated and unarousable. Furthermore, consistently with previous findings based on the mismatch negativity the progression of this decoding performance was informative of patients' chances of awakening (78% predictive of awakening). Our results show for the first time that detection of global regularities at neural level exists despite a deeply unconscious state.

Assessment of the role of LASER-Doppler in the treatment of port-wine stains in infants.

BACKGROUND: Port-wine stains (PWS) are malformations of capillaries in 0.3% of newborn children. The treatment of choice is by pulsed dye LASER (PDL), and requires several sessions. The efficacy of this treatment is at present evaluated on the basis of clinical inspection and of digital photographs taken throughout the treatment. LASER-Doppler imaging (LDI) is a noninvasive method of imaging the perfusion of the tissues by the microcirculatory system (capillaries). The aim of this paper is to demonstrate that LDI allows a quantitative, numerical evaluation of the efficacy of the PDL treatment of PWS. METHOD: The PDL sessions were organized according to the usual scheme, every other month, from September 1, 2012, to September 30, 2013. LDI imaging was performed at the start and at the conclusion of the PDL treatment, and simultaneously on healthy skin in order to obtain reference values. The results evidenced by LDI were analyzed according to the "Wilcoxon signed-rank" test before and after each session, and in the intervals between the three PDL treatment sessions. RESULTS: Our prospective study is based on 20 new children. On average, the vascularization of the PWS was reduced by 56% after three laser sessions. Compared with healthy skin, initial vascularization of PWS was 62% higher than that of healthy skin at the start of treatment, and 6% higher after three sessions. During the 2 months between two sessions, vascularization of the capillary network increased by 27%. CONCLUSION: This study shows that LDI can demonstrate and measure the efficacy of PDL treatment of PWS in children. The figures obtained when measuring the results by LDI corroborate the clinical assessments and may allow us to refine, and perhaps even modify, our present use of PDL and thus improve the efficacy of the treatment.

Distribution de la fraction d'excrétion rénale du lithium et de l'acide urique dans l'étude de population Hercules

Problématique¦L'évaluation fonctionnelle du tubule proximal du rein est intéressante pour la compréhension de la physiopathologie des anomalies du transport du sodium à ce niveau du néphron. Ces anomalies participent au développement de l'hypertension artérielle (HTA) et de la sensibilité au sel. Environ 60% à 80% du sodium est réabsorbé proximalement dans le néphron. Chez l'animal, la fonction du tube proximal peut être estimée directement par microponction. Une telle approche directe n'étant pas possible chez l'homme, seul des approches indirectes permettent de recueillir des informations sur la physiologie de ce segment du néphron, comme par exemple par la mesure de la clairance du lithium (endogène ou exogène) ou de l'acide urique. La fraction d'excrétion du lithium (FELi) et la fraction d'excrétion de l'acide urique (FEAU) permettent d'estimer la réabsorption proximale de sodium chez l'homme. Plusieurs études expérimentales et cliniques ont montré l'existence d'une relation linéaire entre la FELi et la fraction excrétée du sodium (FENa) chez l'animal et l'homme.¦Objectif¦Décrire la distribution de la FELi et de la FEAU et analyser les associations de ces deux variables avec l'âge, le sexe, la consommation d'alcool, le tabagisme, la pression artérielle et l'IMC dans l'étude de population Hercules.¦Méthodes¦Sélection au hasard d'un sous-groupe de participants de l'étude CoLaus (N=6188). Nombre de participants à l'étude Hercules: 437, dont 229 femmes et 208 hommes. Les participants ont effectué une récolte d'urine sur 24 heures afin de déterminer la fonction rénale et les FELi et FEAU. Le TFG a été mesuré à l'aide de la clairance de la créatinine. Le test des rangs signés de Wilcoxon pour données appariées ( Wilcoxon matched-pairs signed rank test) et le test de comparaison des médianes ont été utilisés pour la comparaison entre groupes. Le coefficient de corrélation de Spearman a été utilisé pour évaluer la relation entre les variables continues. Les box-plots ont été utilisés pour la description de la distribution du lithium et de l'acide urique selon l'âge, le sexe et la période de la journée. Le logiciel Stata 11.0 a été utilisé pour les analyses statistiques.¦Résultats¦La prévalence de l'HTA dans la population de l'étude Hercules était 33%, la prévalence du diabète était 8%, la prévalence de l'obésité était 15.3%, la prévalence du tabagisme était 23%. La FELi reste stable avec l'âge et est similaire dans les deux sexes. Chez les hommes, la FELi est plus grande la nuit que le jour, c'est-à-dire qu'ils résorbent plus de sodium proximalement le jour que la nuit. Un IMC plus grand est associé à une FELi plus basse dans les deux sexes. Il y a une corrélation négative entre la FEAU et l'IMC (significative) et la consommation d'alcool.¦Conclusion¦Les résultats obtenus avec les données de l'étude Hercules sont similaires à ceux qu'on retrouve dans la littérature sur la FELi et la FEAU , ce qui rassure sur la qualité des données. La FELi varie peu avec l'âge et le sexe, contrairement à la FEAU, qui varie fortement avec l'âge et le sexe. L'HTA, le diabète, l'obésité, le tabagisme et la consommation d'alcool sont associées à une FELi et FEAU plus basses. Les sujets qui présentent ces caractéristiques réabsorbent donc plus de sodium au niveau proximal.

Contrast-enhanced ultrasound after devascularisation of neuroendocrine liver metastases: functional and morphological evaluation.

OBJECTIVE: To evaluate morphological and perfusion changes in liver metastases of neuroendocrine tumours by contrast-enhanced ultrasound (CEUS) after transarterial embolisation with bead block (TAE) or trans-arterial chemoembolisation with doxorubicin-eluting beads (DEB-TACE). METHODS: In this retrospective study, seven patients underwent TAE, and ten underwent DEB-TACE using beads of the same size. At 1 day before embolisation, 2 days, 1 month and 3 months after the procedure, a destruction-replenishment study using CEUS was performed with a microbubble-enhancing contrast material on a reference tumour. Relative blood flow (rBF) and relative blood volume (rBV) were obtained from the ratio of values obtained in the tumour and in adjacent liver parenchyma. Morphological parameters such as the tumour's major diameter and the viable tumour's major diameter were also measured. A parameter combining functional and morphological data, the tumour vitality index (TVI), was studied. The Wilcoxon rank-sum test and Fisher's test were used to compare treatment groups. RESULTS: At 3 months rBF, rBV and TVI were significantly lower (P = 0.005, P = 0.04 and P = 0.03) for the group with doxorubicin. No difference in morphological parameters was found throughout the follow-up. CONCLUSIONS: One parameter, TVI, could evaluate the morphological and functional response to treatments.

Experimental Uveitis can be Maintained in Rabbits for a Period of Six Weeks After a Safe Sensitization Method.

Abstract Purpose: New treatments against long-lasting uveitis need to be tested. Our aim was to develop a six-week model of uveitis in rabbits. Methods: Rabbits were presensitized with an s.c. injection of Mycobacterium tuberculosis H37RA emulsified with TiterMax® Gold adjuvant. Uveitis was induced at day 28 and 50, by intravitreal challenges of antigen suspension. Ocular inflammation was assessed till euthanasia at day 71 after s.c. injection of M. tuberculosis H37RA by: (a) the number of inflammatory cells in aqueous humor (AH); (b) the protein concentration in AH; (c) the clinical score (mean of conjunctival hyperaemia, conjunctival chemosis, oedema and secretion); (d) the microscopical score (mean presence of fibrin and synechiae, aqueous cell density and aqueous flare grade, as scored by slit lamp). Results: At the sites of presensitization injection, rabbits presented flat nodules which progressively vanished. The first challenge induced a significant increase in the four parameters (p < 0.05 the Wilcoxon/Kruskal-Wallis test). The AH contained 764 ± 82 cells/µl and 32 ± 0.77 mg protein/ml. During the following days, inflammatory parameters decreased slightly. The second intravitreal challenge increased inflammation (3564 ± 228 cells/µl AH and 31 ± 1 mg protein/ml), which remained at a high level for a longer period of time. Conclusion: We developed a model of long-term uveitis, which could be maintained in rabbits for at least six weeks. Such a model could be used to test the efficacy of either new drugs or various drug delivery systems intended to deliver active agents during a few months.

Active and passive screening for tuberculosis in Vaud Canton, Switzerland

Résumé Même si l'incidence de la tuberculose est basse en Suisse, cette maladie reste un problème de santé publique en raison des migrations de populations provenant de pays où l'incidence de la tuberculose est élevée. Les immigrants, à leur arrivée en terre helvétique, doivent s'annoncer auprès d'un des cinq centres d'enregistrement pour les réfugiés (Vallorbe, Bâle, Kreuzlingen, Altstätten et Chiasso) et subir un contrôle médical qui comprend un test tuberculinique et une radiographie du thorax afin de détecter des anomalies compatibles avec une tuberculose. Les requérants avec des signes de maladie sont immédiatement pris en charge dans le but d'éviter une dissémination du bacille de Koch. Cette* étude rétrospective compare la présentation bactériologique et clinique de la tuberculose ainsi que le résultat du traitement de cette maladie chez les immigrants diagnostiqués par dépistage actif (= immigrants venant d'être enregistrés comme requérants d'asile en Suisse) avec d'autres patients diagnostiqués par dépistage passif (= patients suisses, travailleurs étrangers résidents en Suisse ainsi que d'autres étrangers incluant les touristes, les étudiants, les immigrants illégaux ainsi que 11 requérants d'asile détectés tardivement et passivement après leur entrée en Suisse). Parmi les 179 patients, 78% sont des étrangers. La médiane d'âge de la population étrangère atteinte de tuberculose est de 29 ans contre 64 ans pour les Suisses. Le dépistage actif a été effectué auprès de 71 requérants d'asile chez lesquels 49.3% [CI : 37.4 - 61.2] n'avaient pas de symptômes contre 17.6% [Cl : 10.3 - 24.9] chez les 108 passifs. La durée des symptômes était de 2 mois dans le groupe des actifs versus 2.5 mois chez les passifs (ns). L'analyse bactériologique est positive à l'examen direct ou à la culture chez 63.4% des actifs contre 70.4% des passifs (ns). La confirmation bactériologique de la tuberculose chez des patients asymptomatiques s'élevait à 42.2% [Cl : 27.2-57.2] chez les actifs contre 13% [Cl : 5.31-20.7] chez les passifs. Le plus grand danger de dissémination est couru par les patients avec un examen direct positif dont la proportion des asymptomatiques était de 22.2% ([Cl : 9.6-34.8] dans le groupe des actifs contre 11.7% [CI : 4.4-19.0] dans le groupe des passifs. Le résultat du traitement, comprenant les patients guéris (avec confirmation bactériologique de guérison) ainsi que les patients ayant accompli le traitement jusqu'à la fin (mais sans confirmation bactériologique) est similaire dans les groupes des actifs et passifs. Le résultat différent selon le statut légal avec 88% pour les travailleurs étrangers, 85% pour les Suisses, 78% pour les autres étrangers et 83% pour les réfugiés. Ces chiffres sont proches des cibles de l'OMS (85%). Le dépistage actif de la tuberculose permet la détection plus précoce des cas de tuberculose que le dépistage passif. Etant donné que les immigrants proviennent de régions où la prévalence de la tuberculose est supérieure à celle de la Suisse, ce dépistage à la frontière permet non seulement de diminuer la dissémination de cette maladie par la prise en charge immédiate des malades et de réduire la durée des symptômes mais encore de détecter des patients ne présentant aucun symptôme malgré une activité bactériologique positive. Les résultats du traitement ne satisfont pas entièrement aux exigences de l'OMS, ce qui peut être expliqué par le fait que la population de patients tuberculeux suisses étant plus âgés que celles des étrangers, le nombre de décès est plus nombreux (soit par la tuberculose, soit par les complications de maladies sous-jacentes) et que le suivi de patients étrangers est plus difficile car certains disparaissent durant le traitement et d'autres sont transférés ailleurs en Suisse ou retournent dans leur pays. Summary Aim: This retrospective study compared the bacteriological and clinical presentation of tuberculosis and the outcome of treatment in immigrant notified for TB after active screening by chest X-ray at the border with other patients detected by passive screening. Design: Retrospective study of all patients notified for TB in Vaud Canton in 2001 and 2002. Result: In Vaud Canton 78% of the 179 patients notified for TB were foreign-born. Among 71 asylum seekers actively screened at the border, 49.3% [CI 37.4 - 61.2] were symptom-free vs 17.6% [CI 10.3 - 24.9] among 108 passively screened patients. In the passively screened group, the proportion of asymptomatic patients was 15.4% for Swiss patients. 8.6% for foreign workers, and 29.4% for other foreigners. The average duration of symptoms before diagnosis among patients with complaints was 2 months in actively screened foreign-born, compared to 2.5 months in passively screened patients (no significant difference by Wilcoxon-Mann-Whitney test). The proportion of pulmonary TB cases with positive smear or culture was 63.4% in actively screened patients vs 70.4% in passively detected cases. Among actively screened patients with bacteriological confirmation, 42.2% [CI 27.2-57,2] were asymptomatic compared to 13% [CI 5.31-20.7] for passively screened patients. Considering only smear positive patients, the proportion of symptom-free patients was 22.2% [CI 9.6-34.8] in 45 actively screened cases vs 11-7% [4.4 - 19.0] for 77 passive screening. Cure and treatment completion rate for new cases reached 88% for foreign workers, 83% for asylum seekers, 85% for Swiss patients, 78% for other foreigners. Conclusions: Actively screened patients were more frequently asymptomatic than passively detected cases, even when considering only patients with bacteriological confirmation. The active screening by chest X-ray of an immigrant population with a high prevalence of tuberculosis allows the early detection and treatment of tuberculosis. This may contribute to the protection of the resident population for infection. The outcome of treatment for tuberculosis was satisfactory in all population groups.