A novel strategy to translate the biomechanical rupture risk of abdominal aortic aneurysms to their equivalent diameter risk: method and retrospective validation.

OBJECTIVE: To translate the individual abdominal aortic aneurysm (AAA) patient's biomechanical rupture risk profile to risk-equivalent diameters, and to retrospectively test their predictability in ruptured and non-ruptured aneurysms. METHODS: Biomechanical parameters of ruptured and non-ruptured AAAs were retrospectively evaluated in a multicenter study. General patient data and high resolution computer tomography angiography (CTA) images from 203 non-ruptured and 40 ruptured aneurysmal infrarenal aortas. Three-dimensional AAA geometries were semi-automatically derived from CTA images. Finite element (FE) models were used to predict peak wall stress (PWS) and peak wall rupture index (PWRI) according to the individual anatomy, gender, blood pressure, intra-luminal thrombus (ILT) morphology, and relative aneurysm expansion. Average PWS diameter and PWRI diameter responses were evaluated, which allowed for the PWS equivalent and PWRI equivalent diameters for any individual aneurysm to be defined. RESULTS: PWS increased linearly and PWRI exponentially with respect to maximum AAA diameter. A size-adjusted analysis showed that PWS equivalent and PWRI equivalent diameters were increased by 7.5 mm (p = .013) and 14.0 mm (p < .001) in ruptured cases when compared to non-ruptured controls, respectively. In non-ruptured cases the PWRI equivalent diameters were increased by 13.2 mm (p < .001) in females when compared with males. CONCLUSIONS: Biomechanical parameters like PWS and PWRI allow for a highly individualized analysis by integrating factors that influence the risk of AAA rupture like geometry (degree of asymmetry, ILT morphology, etc.) and patient characteristics (gender, family history, blood pressure, etc.). PWRI and the reported annual risk of rupture increase similarly with the diameter. PWRI equivalent diameter expresses the PWRI through the diameter of the average AAA that has the same PWRI, i.e. is at the same biomechanical risk of rupture. Consequently, PWRI equivalent diameter facilitates a straightforward interpretation of biomechanical analysis and connects to diameter-based guidelines for AAA repair indication. PWRI equivalent diameter reflects an additional diagnostic parameter that may provide more accurate clinical data for AAA repair indication.

[Transcranial color-coded sonography in the management of patients with cervical and intracranial arterial stenosis]. / L'écho-Doppler transcrânien dans la prise en charge des sténoses artérielles cervicales et intracrâniennes.

Technological innovations have endowed the development of powerful tools in medical imaging, such as transcranial color-coded sonography. In addition to other imaging techniques, its relevance in cerebrovascular disorders is increasing. This article aims to describe the technique through specification of its current indications in patients with arterial cervical and intracranial stenosis.

[CT coronary angiography for the diagnosis of coronary heart disease]. / Contribution du scanner coronaire au diagnostic de maladie coronarienne.

Coronary computed tomography is an emerging technique for the diagnosis of coronary heart disease. Based on a clinical case, we discuss the diagnostic evaluation of chest pain and the role of coronary CT.

[Cystic lung diseases]. / Les maladies kystiques pulmonaires.

Cystic lung diseases present uncommonly and have an undetermined incidence. Cysts result from a broad spectrum of causative mechanisms and diseases leading to variable clinical presentations. The pathogenic mechanisms that can lead to lung cyst formation include infection, neoplastic, systemic, traumatic, genetic and congenital processes. A rigorous, systemic and multidisciplinary approach is advised in the diagnostic workup of these conditions. In this article, we review cystic lung diseases including their presentation and management.

High levels of 18F-FDG uptake in aortic aneurysm wall are associated with high wall stress.

BACKGROUND: Functional imaging using positron emission tomography (PET) showed increased metabolic activities in the aneurysm wall prior to rupture, whereas separate studies using finite element analysis techniques found the presence of high wall stresses in aneurysms that subsequently ruptured. This case series aimed to evaluate the association between wall stress and levels of metabolic activities in aneurysms of the descending thoracic and abdominal aorta. METHODS: Five patients with aneurysms in the descending thoracic aorta or abdominal aorta were examined using positron emission tomography-computed tomography (PET-CT). Patient-specific models of the aortic aneurysms were reconstructed from CT scans, and wall tensile stresses at peak blood pressure were calculated using the finite element method. Predicted wall stresses were qualitatively compared with measured levels of 18F-fluoro-2-deoxy-glucose (18F-FDG) uptakes in the aneurysm wall. RESULTS: The distribution of wall stress in the aneurysm wall was highly non-uniform depending on the individual geometry. Predicted high wall stress regions co-localised with areas of positive 18F-FDG uptake in all five patients examined. In the two ruptured cases, the locations of rupture corresponded well with regions of elevated metabolic activity and high wall stress. CONCLUSIONS: These preliminary observations point to a potential link between high wall stress and accelerated metabolism in aortic aneurysm wall and warrant further large population-based studies.

[Effect of surgery of pulmonary cysts related to immunoglobulin light chain deposits]. / Intérêt de la chirurgie de kystes pulmonaires liés à des dépôts de chaînes légères.

INTRODUCTION: Light chain deposition disease is a rare anatomo-clinical disorder, which rarely leads to cystic lung destruction. CASE REPORT: We report the case of a 62years old female patient with a history of a monoclonal gammopathy of unknown significance who developed progressive dyspnea. Thoracic CT-scan demonstrated a diffuse pulmonary cystic disorder with predominance in the right lower lobe. Thoracoscopic surgical resection of that lobe led to a diagnosis of non-amyloid kappa light chain deposits. Surgery also resulted in a lung volume reduction effect with clinical and functional benefits related to improved ventilation of adjacent segments. CONCLUSION: This report of pulmonary cystic disorder related to a light chain deposition disease highlights the potential clinical and functional benefits observed after lung volume reduction surgery.

Retroperitoneal abscess from dropped appendicolith complicating laparoscopic appendectomy.

Abscesses can occur after appendectomy. With the increasing use of laparoscopy, this risk has increased in the same way as the incidence of abscesses related to dropped gallstones increased after laparoscopic cholecystectomy. However, this occurrence has been rarely reported. We describe here the case of a young patient who developed retroperitoneal abscess one year after laparoscopic appendectomy.

Left ventricular regional function and maximal exercise capacity in aortic stenosis.

AIMS: The objective assessment of maximal exercise capacity (MEC) using peak oxygen consumption (VO2) measurement may be helpful in the management of asymptomatic aortic stenosis (AS) patients. However, the relationship between left ventricular (LV) function and MEC has been relatively unexplored. We aimed to identify which echocardiographic parameters of LV systolic function can predict MEC in asymptomatic AS. METHODS AND RESULTS: Asymptomatic patients with moderate to severe AS (n = 44, aortic valve area <1.5 cm(2), 66 ± 13 years, 75% of men) and preserved LV ejection fraction (LVEF > 50%) were prospectively referred for resting echocardiography and cardiopulmonary exercise test. LV longitudinal strain (LS) of each myocardial segment was measured by speckle tracking echocardiography (STE) from the apical (aLS) 4-, 2-, and 3-chamber views. An average value of the LS of the analysable segments was provided for each myocardial region: basal (bLS), mid (mLS), and aLS. LV circumferential and radial strains were measured from short-axis views. Peak VO2 was 20.1 ± 5.8 mL/kg/min (median 20.7 mL/kg/min; range 7.2-32.3 mL/kg/min). According to the median of peak VO2, patients with reduced MEC were significantly older (P < 0.001) and more frequently females (P = 0.05). There were significant correlations between peak VO2 and age (r = -0.44), LV end-diastolic volume (r = 0.35), LV stroke volume (r = 0.37), indexed stroke volume (r = 0.32), and E/e' ratio (r = -0.37, all P < 0.04). Parameters of AS severity and LVEF did not correlate with peak VO2 (P = NS for all). Among LV deformation parameters, bLS and mLS were significantly associated with peakVO2 (r = 0.43, P = 0.005, and r = 0.32, P = 0.04, respectively). With multivariable analysis, female gender (ß = 4.9; P = 0.008) and bLS (ß = 0.50; P = 0.03) were the only independent determinants (r(2) = 0.423) of peak VO2. CONCLUSION: In asymptomatic AS, impaired LV myocardial longitudinal function determines reduced MEC. Basal LS was the only parameter of LV regional function independently associated with MEC.

Test-positive rate at CT colonography is increased by rectal bleeding and/or unexplained weight loss, unlike other common gastrointestinal symptoms.

PURPOSE: We evaluated the rate of significant colonic and extra-colonic abnormalities at computed tomography colonography (CTC), according to symptoms and age. MATERIALS AND METHODS: We retrospectively evaluated 7361 consecutive average-risk subjects (3073 males, average age: 60.3 ± 13.9; range 18-96 years) for colorectal cancer (CRC) who underwent CTC. They were divided into three groups according to clinical symptoms: 1343 asymptomatic individuals (group A), 899 patients with at least one "alarm" symptom for CRC, including rectal bleeding and unexplained weight loss (group C), and 5119 subjects with other gastrointestinal symptoms (group B). Diagnostic and test-positive rates of CTC were established using optical colonoscopy (OC) and/or surgery as reference standard. In addition, clinically significant extra-colonic findings were noted. RESULTS: 903 out of 7361 (12%, 95% confidence interval (CI) 0.11-0.13) subjects had at least one clinically significant colonic finding at CTC. CTC true positive fraction and false positive fraction were respectively 637/642 (99.2%, 95%CI 0.98-0.99) and 55/692 (7.95%, 95%CI 0.05-0.09). The pooled test-positive rate in group C (138/689, 20.0%, 95%CI 0.17-0.23) was significantly higher than in both groups A (79/1343, 5.9%, 95%CI 0.04-0.07) and B (420/5329, 7.5%, 95%CI 0.07-0.08) (p < 0.001). Aging and male gender were associated to a higher test positive rate. The rate of clinically significant extra-colonic findings was significantly higher in group C (44/689, 6.4%, 95%CI 0.04-0.08) versus groups A (26/1343, 1.9%, 95%CI 0.01-0.02) and B (64/5329, 1.2%, 95%CI 0.01-0.02) (p < 0.001). CONCLUSION: Both test-positive and significant extra-colonic finding rates at CTC are significantly increased in the presence of "alarm" gastrointestinal symptoms especially in older patients.

[Retrocaval ureter in a 10-year-old boy]. / Uretère rétrocave chez un enfant de dix ans.

Retrocaval ureter is an uncommon abnormality of the inferior vena cava, which is rarely detected in the child due to its non-specific symptomatology. Despite a varying state of severity, chronic ureteral obstruction generally leads to the deterioration of renal function during adulthood. Treatment depends on the symptomatology in question, and surgical management should be as conservative as possible.

[Diagnosis and follow-up of a large intrahepatic portocaval fistula in a newborn]. / Diagnostic et suivi d'une large fistule porto-cave intrahépatique chez un nouveau-né.

Portocaval fistulas are rare and only exceptionally discovered in newborns. We report the case of a large portocaval fistula associated with portal hypoperfusion detected at Doppler US imaging in an otherwise asymptomatic 5 week old infant. The patient remained asymptomatic over the following two years. At that time, preoperative angiogram showed a normal portal venous system and the fistula was surgically closed. Postoperative US showed a normal and patent portal system, without evidence of portal hypertension.

[Traumatic luxation of the posterior tibialis tendon]. / Luxation traumatique du tendon du tibialis posterior.

Anterior dislocation of the tibialis posterior tendon is a traumatic lesion, which is rarely suspected following ankle trauma. It seems to be promoted by hypoplasia of the retromalleolar sulcus. Surgical treatment is easy and reportedly gives excellent results, but the diagnosis is difficult and absence of diagnosis may result in functional instability of the foot requiring more invasive surgical treatment.

[Diagnosis of internal carotid artery dissection. Two case reports]. / Approche diagnostique de la dissection carotidienne. A propos de deux cas.

Two cases of acute internal carotid dissection are presented. Typical symptoms, pathogeny and imaging features are reviewed. Magnetic Resonance is actually the best technique for the diagnosis of internal carotid artery dissection, which should be searched in young patients presenting neurologic and cervico-facial symptoms.

Myocardial dynamic contrast-enhanced Mr: vascular diseases and beyond.

Contrast-enhanced cardiac magnetic resonance imaging allows the evaluation of both myocardial perfusion and myocardial tissue characteristics. This paper reviews different microvascular and non-vascular conditions that can cause abnormal findings on contrast-enhanced myocardial magnetic resonance imaging. Knowledge of their characteristics can avoid misinterpretation and avoid inappropriate referral for further invasive imaging in patients suspected of myocardial vascular disease.

Screening for colorectal cancer in asymptomatic average risk patients: role of imaging.

Early detection of colorectal cancer or advanced adenomas is a public health priority in many industrialized countries. There are various methods of screening average risk individuals for colorectal cancer, and their effectiveness may depend on subjective parameters like local expertise and patient's preferences. This paper reviews these tests with special emphasis regarding imaging techniques that aim to provide less-invasive alternatives to optical colonoscopy (OC) which is the standard of reference. Both Double-Contrast Barium Enema (DCBE) and Virtual Colonoscopy (VC) have >90% sensitivity compared to OC in the detection of clinically relevant colonic lesions. Nevertheless, VC may have an edge over DCBE for technical and reproductivity reasons, as well as greater learning opportunities. Imaging techniques criticisms regarding diminutive and flat lesions, cost, radiation exposure and effects on gastroenterological practice are addressed.

Relationship between the extent of deep venous thrombosis and the extent of acute pulmonary embolism as assessed by CT angiography.

The aim of our study is to investigate prospectively the quantitative relationship between deep venous thrombosis (DVT) and acute pulmonary embolism (PE). 110 patients clinically suspected of having venous thromboembolic disease underwent combined CT pulmonary angiography (CTPA) and venography of lower limb veins. 44 patients presented with clinical signs of DVT and positive ultrasonography or ascending venography, but no clinical sign of PE (Group 1). 66 patients presented with clinical signs of PE and positive CTPA (Group 2). Clot load in lower limb veins and pulmonary arteries were scored by two independent readers, each using two separate systems for DVT and two for PE. 27 (61%) patients in Group 1 also had PE, and 55 (83%) patients in Group 2 also had DVT. Correlations between PE and DVT scores were weak but statistically significant in Group 2 (r(s) ranging from 0.470-0.520; p< or =0.001), but only some were significant in Group 1 (r(s) ranging from 0.253-0.318; p-values ranging from 0.035-0.097). In conclusion, although PE occurs in a majority of patients with DVT, and vice versa, the amount/burden of clot load in one condition does not necessarily indicate - or indicates only weakly - the degree of burden in the other condition.