In Vivo Computed Tomography as a Research Tool to Investigate Asthma and COPD: Where Do We Stand?

Computed tomography (CT) is a clinical tool widely used to assess and followup asthma and chonic obstructive pulmonary disease (COPD) in humans. Strong efforts have been made the last decade to improve this technique as a quantitative research tool. Using semiautomatic softwares, quantification of airway wall thickness, lumen area, and bronchial wall density are available from large to intermediate conductive airways. Skeletonization of the bronchial tree can be built to assess its three-dimensional geometry. Lung parenchyma density can be analysed as a surrogate of small airway disease and emphysema. Since resident cells involve airway wall and lung parenchyma abnormalities, CT provides an accurate and reliable research tool to assess their role in vivo. This litterature review highlights the most recent advances made to assess asthma and COPD with CT, and also their drawbacks and the place of CT in clarifying the complex physiopathology of both diseases

Unexpected Coexisting Myocardial Infarction Detected by Delayed Enhancement MRI

We report a case of an unexpected coexisting anterior myocardial infarction detected by delayed enhancement MRI in a 41-year-old man following a presentation with a first episode of chest pain during inferior acute myocardial infarction. This second necrotic area was not initially suspected because there were no ECG changes in the anterior leads and the left descending coronary artery did not present any significant stenoses on emergency coronary angiography. Unrecognised myocardial infarction may carry important prognostic implications. CMR is currently the best imaging technique to detect unexpected infarcts

Virus-Negative Active Lymphocytic Myocarditis Progressing to a Fibrotic Stage

We report a fairly special case of lymphocytic myocarditis progressing to a fibrotic stage, described using multimodality imaging and confirmed on histopathology. This paper presents an uncommon diagnosis with a probable guarded prognosis

Additional value of three-dimensional echocardiography in patients with cardiac resynchronization therapy

SummaryBackgroundThere is no gold standard technique for quantification of ventricular dyssynchrony.AimTo investigate whether additional real-time three-dimensional morphologic assessment of ventricular dyssynchrony affects response after biventricular pacing.MethodsForty-one patients with severe heart failure were implanted with a biventricular pacing device and underwent two-dimensional (time dispersion of 12 left ventricular electromechanical delays) and three-dimensional echocardiographic assessment of ventricular dyssynchrony (dispersion of time to minimum regional volume for 16 left ventricular segments), before implantation, 2 days postimplantation with optimization of the pacing interventricular delay and 6 months postimplantation.ResultsIndividual optimization of sequential biventricular pacing based on three-dimensional ventricular dyssynchrony provided more improvement (p<0.05) in left ventricular ejection fraction and cardiac output than simultaneous biventricular pacing. During the different configurations of sequential biventricular pacing, the changes in three-dimensional ventricular dyssynchrony were highly correlated with those of cardiac output (r=−0.67, p<0.001) and ejection fraction (r=−0.68, p<0.001). The correlations between two-dimensional ventricular dyssynchrony and cardiac output or ejection fraction were significant but less (r=−0.60, p<0.01 and r=−0.56, p<0.05, respectively). After 6 months, 76% of patients were considered responders (10% decrease in end-systolic volume). Before implantation, we observed a significant difference between responders and non-responders in terms of three-dimensional (p<0.05) – but not two-dimensional – ventricular dyssynchrony.ConclusionThis prospective study demonstrated the additional value of three-dimensional assessment of ventricular dyssynchrony in predicting response after biventricular pacing and optimizing the pacing configuration

Automated Quantification of Right Ventricular Fat at Contrast-enhanced Cardiac Multidetector CT in Arrhythmogenic Right Ventricular Cardiomyopathy

International audiencePurpose: To evaluate an automated method for the quantification of fat in the right ventricular (RV) free wall on multidetector computed tomography (CT) images and assess its diagnostic value in arrhythmogenic RV cardiomyopathy (ARVC). Materials and Methods: This study was approved by the institutional review board, and all patients gave informed consent. Thirty-six patients with ARVC (mean age 6 standard deviation, 46 years 6 15; seven women) were compared with 36 age-and sex-matched subjects with no structural heart disease (control group), as well as 36 patients with ischemic cardiomyopathy (ischemic group). Patients underwent contrast material– enhanced electrocardiography-gated cardiac multidetector CT. A 2-mm-thick RV free wall layer was automatically segmented and myocardial fat, expressed as percentage of RV free wall, was quantified as pixels with attenuation less than 210 HU. Patient-specific segmentations were registered to a template to study fat distribution. Receiver operating characteristic (ROC) analysis was performed to assess the diagnostic value of fat quantification by using task force criteria as a reference. Results: Fat extent was 16.5% 6 6.1 in ARVC and 4.6% 6 2.7 in non-ARVC (P , .0001). No significant difference was observed between control and ischemic groups (P = .23). A fat extent threshold of 8.5% of RV free wall was used to diagnose ARVC with 94% sensitivity (95% confidence interval [CI]: 82%, 98%) and 92% specificity (95% CI: 83%, 96%). This diagnostic performance was higher than the one for RV volume (mean area under the ROC curve, 0.96 6 0.02 vs 0.88 6 0.04; P = .009). In patients with ARVC, fat correlated to RV volume (R = 0.63, P , .0001), RV function (R = 20.67, P = .001), epsilon waves (R = 0.39, P = .02), inverted T waves in V 1 –V 3 (R = 0.38, P = .02), and presence of PKP2 mutations (R = 0.59, P = .02). Fat distribution differed between patients with ARVC and those without, with posterolateral RV wall being the most ARVC-specific area

Integrated hybrid Raman/fiber Bragg grating interrogation scheme for distributed temperature and point dynamic strain measurements

We propose and experimentally demonstrate the feasibility of an integrated hybrid optical fiber sensing interrogation technique that efficiently combines distributed Raman-based temperature sensing with fiber Bragg grating (FBG)-based dynamic strain measurements. The proposed sensing system is highly integrated, making use of a common optical source/receiver block and exploiting the advantages of both (distributed and point) sensing technologies simultaneously. A multimode fiber is used for distributed temperature sensing, and a pair of FBGs in each discrete sensing point, partially overlapped in the spectral domain, allows for temperature-independent discrete strain measurements. Experimental results report a dynamic strain resolution of 7.8  nε/√Hz within a full range of 1700 με and a distributed temperature resolution of 1°C at 20 km distance with 2.7 m spatial resolution

Large kidneys predict poor renal outcome in subjects with diabetes and chronic kidney disease

<p>Abstract</p> <p>Background</p> <p>Renal hypertrophy occurs early in diabetic nephropathy, its later value is unknown. Do large kidneys still predict poor outcome in patients with diabetes and Chronic Kidney Disease (CKD)?</p> <p>Methods</p> <p>Seventy-five patients with diabetes and CKD according to a Glomerular Filtration Rate (GFR, by 51Cr-EDTA clearance) below 60 mL/min/1.73 m²or an Albumin Excretion Rate above 30 mg/24 H, had an ultrasound imaging of the kidneys and were cooperatively followed during five years by the Diabetology and Nephrology departments of the Centre Hospitalier Universitaire de Bordeaux.</p> <p>Results</p> <p>The patients were mainly men (44/75), aged 62 ± 13 yrs, with long-standing diabetes (duration:17 ± 9 yrs, 55/75 type 2), and CKD: initial GFR: 56.5 (8.5-209) mL/min/1.73 m², AER: 196 (20-2358) mg/24 H. Their mean kidney lenght (108 ± 13 mm, 67-147) was correlated to the GFR (r = 0.23, p < 0.05). During the follow-up, 9/11 of the patients who had to start dialysis came from the half with the largest kidneys (LogRank: p < 0.05), despite a 40% higher initial isotopic GFR. Serum creatinine were initially lower (Small kidneys: 125 (79-320) μmol/L, Large: 103 (50-371), p < 0.05), but significantly increased in the "large kidneys" group at the end of the follow-up (Small kidneys: 129 (69-283) μmol/L, Large: 140 (50-952), p < 0.005 vs initial). The difference persisted in the patients with severe renal failure (KDOQI stages 4,5).</p> <p>Conclusions</p> <p>Large kidneys still predict progression in advanced CKD complicating diabetes. In these patients, ultrasound imaging not only excludes obstructive renal disease, but also provides information on the progression of the renal disease.</p

Traitement quantitatif des images en tomodensitométrie thoracique (application à l'image fonctionnelle des bronches et du coeur)

L'imagerie TDM du thorax est un outil essentiel de l'évaluation morphologique des bronches et des cavités cardiaques. Le développement de l'imagerie fonctionnelle est conditionné, d'une part à l'application de techniques de synchronisation de l'acquisition aux signaux physiologiques, d'autre part au développement et à la validation de méthodes de traitement d'images. Nous avons analysé l'apport de la synchronisation à l'ECG lors de l'évaluation qualitative des images pulmonaires. Nous avons également validé une méthode de traitement d'images qui permet la mesure des surfaces de section et de l'épaisseur des parois bronchiques. Ces mesures se sont avérées pertinentes pour l'exploration des bronchopneumopathies obstructives et de la mucoviscidose. Nous avons enfin appliqué une méthode de quantification volumique à des acquisitions tomodensitométriques cardiaques et validé son utilisation pour la mesure des volumes des cavités ventriculaires.Computed tomography of the thorax is a fundamental imaging technique for morphological evaluation of bronchi and heart chambers. The development of functional imaging depends, on one hand, on the ability to synchronise CT acquisitions to a physiological signal, on the other hand, on the development and validation of image processing and analysis. We have demonstrated the benefit of ECG-triggered acquisitions for quantitative analysis of pulmonary images. We have also validated a method of image processing and analysis allowing assessment of bronchial wall and bronchial lumen areas. These measurements were efficient in the evaluation of chronic obstructive pulmonary diseases nd cystic fibrosis. Then, we have applied a technique of image processing and analysis to CT images of the heart and validated its use in ventricular volume assessment.BORDEAUX2-BU Santé (330632101) / SudocSudocFranceF