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Objective: To develop a new method for the cardiac MR (CMR) quantification of peri-infarct ischaemia using fused perfusion and delayed-enhanced images and to evaluate this method using quantitative single photon emission CT (SPECT) imaging as a reference. Methods: 40 patients presenting with peri-infarct ischaemia on a routine stress 99mTc-SPECT imaging were recruited. Within 8 days of the SPECT study, myocardial perfusion was evaluated using stress adenosine CMR. Using fused perfusion and delayed-enhanced images, peri-infarct ischaemia was quantified as the percentage of myocardium with stress-induced perfusion defect that was adjacent to and larger than a scar. This parameter was compared with both the percent myocardium ischaemia (SD%) and the ischaemic total perfusion deficit (TPD). The diagnostic performance of CMR in detection of significant coronary artery stenosis (of ⩾70%) was also determined. Results: On SPECT imaging, in addition to peri-infarct ischaemia, reversible perfusion abnormalities were detected in a remote zone in seven patients. In the 33 patients presenting with only peri-infarct ischaemia, the agreement between CMR peri-infarct ischaemia and both SD% and ischaemic TPD was excellent [intraclass coefficient of correlation (ICC) = 0.969 and ICC = 0.877, respectively]. CMR-defined peri-infarct ischaemia for the detection of a significant coronary artery stenosis showed an areas under receiver-operating characteristic curve of 0.856 (95% confidence interval, 0.680-0.939). The best cut-off value was 8.1% and allowed a 72% sensitivity, 96% specificity, 60% negative predictive value and 97% positive predictive value. Conclusion: This proof-of-concept study shows that CMR imaging has the potential as a test for quantification of peri-infarct ischaemia. Advances in knowledge: This study demonstrates the proof of concept of a commonly known intuitive idea, that is, evaluating the peri-infarct ischaemic burden by subtracting delayed enhancement from first-pass perfusion imaging on CMR. [ABSTRACT FROM AUTHOR]

The aim of our study was to evaluate the feasibility of non-invasive respiratory-gated micro-computed tomography (micro-CT) for assessment of airway remodelling in a mouse asthma model. Six female BALB/c mice were challenged intranasally with ovalbumin. A control group of six mice received saline inhalation. All mice underwent plethysmographic study and micro-CT. For each mouse, peribronchial attenuation values of 12 bronchi were measured, from which a peribronchial density index (PBDI) was computed. Mice were then sacrificed and lungs examined histologically. Final analysis involved 10 out of 12 mice. Agreement of measurements across observers and over time was very good (intraclass correlation coefficients: 0.94-0.98). There was a significant difference in PBDI between asthmatic and control mice (-210 vs. -338.9 HU, P = 0.008). PBDI values were correlated to bronchial muscle area (r = 0.72, P = 0.018). This study shows that respiratory-gated micro-CT may allow non-invasive monitoring of bronchial remodelling in asthmatic mice and evaluation of innovative treatment effects. [ABSTRACT FROM AUTHOR]

The assessment of airway dimensions in patients with airway disease by using computed tomography (CT) has been limited by the obliquity of bronchi, the ability to identify the bronchial generation, and the limited number of bronchial measurements. The aims of the present study were (i) to analyze cross-sectional bronchial dimensions after automatic orthogonal reconstruction of all visible bronchi on CT images, and (ii) to compare bronchial morphometry between smokers and nonsmokers. CT and pulmonary function tests were performed in 18 males separated into two groups: 9 nonsmokers and 9 smokers. Bronchial wall area (WA) and lumen area (LA) were assessed using dedicated 3D software able to provide accurate cross-sectional measurements of all visible bronchi on CT. WA/LA and WA/(WA+LA) ratios were computed and all parameters were compared between both groups. Smokers demonstrated greater WA, smaller LA, and consequently greater LA/WA and LA/(WA+LA) ratios than nonsmokers. These differences occurred downward starting at the fourth bronchial generation. 3D quantitative CT method is able to demonstrate significant changes in bronchial morphometry related to tobacco consumption. [ABSTRACT FROM AUTHOR]

To assess both sensitivity and specificity of digital chest radiography alone and in conjunction with dual-exposure dual-energy chest radiography for the detection and classification of pulmonary nodules. One hundred patients with a total of 149 lung nodules (3-45 mm; median, 11 mm) confirmed by CT were included in this study. Dual-exposure dual-energy chest radiographies of each patient were obtained using a CsI detector system. Experienced board-certified chest radiologists from four different medical centers in Europe reviewed standard chest radiographs alone and in conjunction with dual-energy images blinded and in random order. The reviewers rated the probability of presence, calcification and malignancy of all lung nodules on a five-point rating scale. Lesions detected were identified by applying a specific coordinate system to enable precise verification by the study leader. A receiver-operating characteristic (ROC) analysis was performed. In addition to the 149 true-positive CT proven lesions, 236 false-positive lung nodules were described in digital chest radiographies in conjunction with dual-energy chest radiographies. The cumulative sensitivity of chest radiography in conjunction with dual energy was 43%, specificity was 55%. For digital radiography alone, sensitivity was 35% and specifity was 83%. For the dual energy system, positive predictive value was 58%, and negative predictive value was 66% compared to the digital radiography with a positive predictive value of 59% and a negative predictive value of 65%. Areas under the curve in a ROC analysis resulted in 0.631 (95% confidence interval =0.61 to 0.65) for radiography with dual energy and 0.602 (95% confidence interval =0.58 to 0.63) for digital radiography alone. This difference was not statistically significant. For the detection of lesion calcification or the determination of malignancy, ROC analysis also failed to show significant differences. CsI-based flat-panel dual-exposure dual-energy imaging added to standard chest radiography did not show statistically significant improvement for the detection of pulmonary nodules, nor the identification of calcifications, nor the determination of malignancy. [ABSTRACT FROM AUTHOR]

To compare MRI findings of left ventricular apical ballooning syndrome (LVABS) with those of acute myocardial infarction (AMI). Fifteen patients with a LVABS (group 1) and 25 patients with an AMI (group 2) were explored by MRI within 24 h after admission. Comparison of both groups for the number and location of myocardial segments with abnormal wall motion and abnormal perfusion or delayed enhancement was performed. The number of involved segments was higher in group 1 than in group 2 (p<0.001). In group 1, segments with abnormal wall motion were distributed in more than one vascular territory in all patients and confined to the medial, distal, and apical regions of the left ventricle. Subendocardial hypoenhancement was observed in 16/25 patients (64%) in group 2 and in none of group 1 (p<0.001). All patients in group 2 demonstrated delayed-enhancement abnormalities in a vascular distribution, whereas none in group 1 presented this abnormality (p<0.001). Diffusely distributed segmental wall-motion abnormalities and absence of first-pass perfusion hypoenhancement and of delayed enhancement at MRI help to differentiate LVABS from AMI. In the acute phase or in some difficult cases, cardiac MRI should become routine to confirm the diagnosis of LVABS. [ABSTRACT FROM AUTHOR]

Study Objectives: The purpose of this study was to assess the clinical follow-up of a negative spiral CT (SCT) angiographic finding after a suspicion of acute pulmonary embolism (PE) in a population of inpatients with cardiac and/or respiratory disease. In this high-risk population, clinical findings suggestive of PE are frequently misleading.Design: One hundred seventy-five consecutive patients hospitalized in cardiac and pneumology wards underwent SCT angiography for suspected PE over a 30-month period. Angiographic findings were positive in one third. For the 117 patients with negative SCT angiographic findings, a clinical follow-up during a minimum of 6 months was assessed, particularly in relation to recurrent thromboembolism, mortality, and cause of death.Results: The mean +/- SD follow-up was 21 +/- 11.5 months, and five patients were unavailable for follow-up. Of the 117 patients with negative findings, 81 patients did not receive anticoagulant therapy and 46 patients received anticoagulation for cardiac disease or deep venous thrombosis. Twenty-two patients died during the follow-up period, 3 of them during the first 3 months following the initial event from an undetermined cause. In patients still alive, a new PE occurred in two cases. Patients with a poor cardiopulmonary reserve did not present any recurrent events. In this population, tests other than imaging (d-dimers, cardiac echocardiography, or venous ultrasound) contributed little to eliminate the diagnosis of PE.Conclusions: Whether or not early deaths are considered or not to be related to a recurrent PE, the rate of recurrence after a negative SCT angiographic finding varied between 1.8% and 4.9%. SCT angiography can be used confidently to rule out significant PE, and may prevent further investigations and unnecessary treatment in an inpatient population with cardiac and/or respiratory diseases. [ABSTRACT FROM AUTHOR]

Abstract Background 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)? Methods Seventy-five patients with diabetes and CKD according to a Glomerular Filtration Rate (GFR, by 51Cr-EDTA clearance) below 60 mL/min/1.73 m2 or 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. Results 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). Conclusions 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.