Le scanner dans les pathologies aortiques, de la valve au syndrome aortique aigu en passant par les anévrysmes et les vascularites

Université Paris-Diderot, CHU Beaujon, Paris, France, The IVth Congress of Radiology and Medical Imaging of the Republic of Moldova with international participation, Chisinau, May 31 – June 2, 2018Introduction: L’aorte est menacée de plusieurs processus pathologiques, la plupart pouvant se localiser à n’importe quel niveau de l’aorte. Les plus fréquents sont l’athérome (et ses complications emboliques), les anévrismes et les dissections. Plus rarement sont observés au niveau thoracique les ulcères aortiques et les hématomes pariétaux, les atteintes inflammatoires au cours des vascularites (Artérite à cellules géantes, Takayasu, Behcet) sans oublier les ruptures traumatiques de l’isthme. La valve aortique est également menacée par les rétrécissements notamment dans le cadre de l’athérome, et beaucoup plus rarement par des localisations infectieuses d’endocardite. Contenu: Le scanner et l’IRM, grâce à leurs performances sans cesse en progression, sont devenus incontournables pour le diagnostic des maladies de l’aorte, le planning préopératoire et le suivi. Le rôle de chacune de ces modalités avec leurs avantages et limites respectifs, sont à bien connaitre pour assurer la prise en charge la plus adaptée. De nombreuses recommandations européennes et américaines aident de surcroît à établir les meilleures stratégies diagnostiques. Conclusions: Techniquement, l’idéal est d’examiner l’aorte sur toute sa hauteur, depuis l’origine des troncs supra-aortiques jusqu’aux artères fémorales. Les nouveaux scanners parviennent à couvrir ce champ en une seule apnée. En IRM, la couverture est limitée à 50 cm ce qui conduit soit à privilégier un segment aortique par rapport à l’autre, soit à faire 2 centrages successifs et 2 injections de produit de contraste à condition de s’être assuré que la fonction rénale est normale

Interet du scanner multibarrettes dans le diagnostic d’embolie pulmonaire

A fost evidenţiată importanţa tomografiei computerizate spiralate în diagnosticul emboliei pulmoare

Diagnosis of obstructive coronary artery disease using computed tomography angiography in patients with stable chest pain depending on clinical probability and in clinically important subgroups: meta-analysis of individual patient data

OBJECTIVE: To determine whether coronary computed tomography angiography (CTA) should be performed in patients with any clinical probability of coronary artery disease (CAD), and whether the diagnostic performance differs between subgroups of patients. DESIGN: Prospectively designed meta-analysis of individual patient data from prospective diagnostic accuracy studies. DATA SOURCES: Medline, Embase, and Web of Science for published studies. Unpublished studies were identified via direct contact with participating investigators. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Prospective diagnostic accuracy studies that compared coronary CTA with coronary angiography as the reference standard, using at least a 50% diameter reduction as a cutoff value for obstructive CAD. All patients needed to have a clinical indication for coronary angiography due to suspected CAD, and both tests had to be performed in all patients. Results had to be provided using 2×2 or 3×2 cross tabulations for the comparison of CTA with coronary angiography. Primary outcomes were the positive and negative predictive values of CTA as a function of clinical pretest probability of obstructive CAD, analysed by a generalised linear mixed model; calculations were performed including and excluding non-diagnostic CTA results. The no-treat/treat threshold model was used to determine the range of appropriate pretest probabilities for CTA. The threshold model was based on obtained post-test probabilities of less than 15% in case of negative CTA and above 50% in case of positive CTA. Sex, angina pectoris type, age, and number of computed tomography detector rows were used as clinical variables to analyse the diagnostic performance in relevant subgroups. RESULTS: Individual patient data from 5332 patients from 65 prospective diagnostic accuracy studies were retrieved. For a pretest probability range of 7-67%, the treat threshold of more than 50% and the no-treat threshold of less than 15% post-test probability were obtained using CTA. At a pretest probability of 7%, the positive predictive value of CTA was 50.9% (95% confidence interval 43.3% to 57.7%) and the negative predictive value of CTA was 97.8% (96.4% to 98.7%); corresponding values at a pretest probability of 67% were 82.7% (78.3% to 86.2%) and 85.0% (80.2% to 88.9%), respectively. The overall sensitivity of CTA was 95.2% (92.6% to 96.9%) and the specificity was 79.2% (74.9% to 82.9%). CTA using more than 64 detector rows was associated with a higher empirical sensitivity than CTA using up to 64 rows (93.4% v 86.5%, P=0.002) and specificity (84.4% v 72.6%, P<0.001). The area under the receiver-operating-characteristic curve for CTA was 0.897 (0.889 to 0.906), and the diagnostic performance of CTA was slightly lower in women than in with men (area under the curve 0.874 (0.858 to 0.890) v 0.907 (0.897 to 0.916), P<0.001). The diagnostic performance of CTA was slightly lower in patients older than 75 (0.864 (0.834 to 0.894), P=0.018 v all other age groups) and was not significantly influenced by angina pectoris type (typical angina 0.895 (0.873 to 0.917), atypical angina 0.898 (0.884 to 0.913), non-anginal chest pain 0.884 (0.870 to 0.899), other chest discomfort 0.915 (0.897 to 0.934)). CONCLUSIONS: In a no-treat/treat threshold model, the diagnosis of obstructive CAD using coronary CTA in patients with stable chest pain was most accurate when the clinical pretest probability was between 7% and 67%. Performance of CTA was not influenced by the angina pectoris type and was slightly higher in men and lower in older patients. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42012002780

Diagnosis of obstructive coronary artery disease using computed tomography angiography in patients with stable chest pain depending on clinical probability and in clinically important subgroups: Meta-analysis of individual patient data

Objective To determine whether coronary computed tomography angiography (CTA) should be performed in patients with any clinical probability of coronary artery disease (CAD), and whether the diagnostic performance differs between subgroups of patients. Design Prospectively designed meta-analysis of individual patient data from prospective diagnostic accuracy studies. Data sources Medline, Embase, and Web of Science for published studies. Unpublished studies were identified via direct contact with participating investigators. Eligibility criteria for selecting studies Prospective diagnostic accuracy studies that compared coronary CTA with coronary angiography as the reference standard, using at least a 50% diameter reduction as a cutoff value for obstructive CAD. All patients needed to have a clinical indication for coronary angiography due to suspected CAD, and both tests had to be performed in all patients. Results had to be provided using 2×2 or 3×2 cross tabulations for the comparison of CTA with coronary angiography. Primary outcomes were the positive and negative predictive values of CTA as a function of clinical pretest probability of obstructive CAD, analysed by a generalised linear mixed model; calculations were performed including and excluding non-diagnostic CTA results. The no-treat/treat threshold model was used to determine the range of appropriate pretest probabilities for CTA. The threshold model was based on obtained post-test probabilities of less than 15% in case of negative CTA and above 50% in case of positive CTA. Sex, angina pectoris type, age, and number of computed tomography detector rows were used as clinical variables to analyse the diagnostic performance in relevant subgroups. Results Individual patient data from 5332 patients from 65 prospective diagnostic accuracy studies were retrieved. For a pretest probability range of 7-67%, the treat threshold of more than 50% and the no-treat threshold of less than 15% post-test probability were obtained using CTA. At a pretest probability of 7%, the positive predictive value of CTA was 50.9% (95% confidence interval 43.3% to 57.7%) and the negative predictive value of CTA was 97.8% (96.4% to 98.7%); corresponding values at a pretest probability of 67% were 82.7% (78.3% to 86.2%) and 85.0% (80.2% to 88.9%), respectively. The overall sensitivity of CTA was 95.2% (92.6% to 96.9%) and the specificity was 79.2% (74.9% to 82.9%). CTA using more than 64 detector rows was associated with a higher empirical sensitivity than CTA using up to 64 rows (93.4% v 86.5%, P=0.002) and specificity (84.4% v 72.6%, P<0.001). The area under the receiver-operating-characteristic curve for CTA was 0.897 (0.889 to 0.906), and the diagnostic performance of CTA was slightly lower in women than in with men (area under the curve 0.874 (0.858 to 0.890) v 0.907 (0.897 to 0.916), P<0.001). The diagnostic performance of CTA was slightly lower in patients older than 75 (0.864 (0.834 to 0.894), P=0.018 v all other age groups) and was not significantly influenced by angina pectoris type (typical angina 0.895 (0.873 to 0.917), atypical angina 0.898 (0.884 to 0.913), non-anginal chest pain 0.884 (0.870 to 0.899), other chest discomfort 0.915 (0.897 to 0.934)). Conclusions In a no-treat/treat threshold model, the diagnosis of obstructive CAD using coronary CTA in patients with stable chest pain was most accurate when the clinical pretest probability was between 7% and 67%. Performance of CTA was not influenced by the angina pectoris type and was slightly higher in men and lower in older patients. Systematic review registration PROSPERO CRD42012002780

COMPARAISON DES DIFFERENTES SEQUENCES IRM DANS L'EXPLORATION DES MYOCARDITES AIGUES

PARIS6-Bibl.Pitié-Salpêtrie (751132101) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Evaluation de la qualité des prescriptions des examens radiologiques d'abdomen sans préparation (ASP) dans deux services d'urgences parisiens

PARIS6-Bibl. St Antoine CHU (751122104) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Acute enlargement, morphological changes, and rupture of intracranial infectious aneurysm in infective endocarditis. Serial imaging

International audienceA 72-year-old man received a transcatheter aortic valve implantation (TAVI) 2 years ago for leakage of the degenerative bioprosthesis with Corevalve n°31 implantation, presented infective endocarditis (IE) (streptococcus sanguinis) of the bioprosthetic aortic valve. One month after antibiotic treatment was initiated, he presented a left-sided hemiplegia, a right frontal hematoma. MRI/contrast-enhanced magnetic resonance angiography (CE-MRA) revealed 2 infectious intracranial aneurysms (IIAs) of the right (10 mm) and left middle cerebral artery (MCA) (M2 segment, 5 mm). The right MCA IIA was treated within 1 day by glue-embolization. Seven days later, the patient acutely developed motor aphasia. CE-MRA showed significant enlargement (15 mm) and morphologic change of the ruptured left MCA IIA. This IIA was treated with Onyx-embolization. This case adds additional evidence that IIAs, during IE, can show rapid growth and morphological change over a 7 day course and emphasizes the imperative need of close imaging follow-up when IIAs are managed by antibiotic therapy