Efficacy of Chest CT for COVID-19 Pneumonia Diagnosis in France.

Background The role and performance of chest CT in the diagnosis of the coronavirus disease 2019 (COVID-19) pandemic remains under active investigation. Purpose To evaluate the French national experience using chest CT for COVID-19, results of chest CT and reverse transcription polymerase chain reaction (RT-PCR) assays were compared together and with the final discharge diagnosis used as the reference standard. Materials and Methods A structured CT scan survey (NCT04339686) was sent to 26 hospital radiology departments in France between March 2, 2020, and April 24, 2020. These dates correspond to the peak of the national COVID-19 epidemic. Radiology departments were selected to reflect the estimated geographic prevalence heterogeneities of the epidemic. All symptomatic patients suspected of having COVID-19 pneumonia who underwent both initial chest CT and at least one RT-PCR test within 48 hours were included. The final discharge diagnosis, based on multiparametric items, was recorded. Data for each center were prospectively collected and gathered each week. Test efficacy was determined by using the Mann-Whitney test, Student t test, χ2 test, and Pearson correlation coefficient. P < .05 indicated a significant difference. Results Twenty-six of 26 hospital radiology departments responded to the survey, with 7500 patients entered; 2652 did not have RT-PCR test results or had unknown or excess delay between the RT-PCR test and CT. After exclusions, 4824 patients (mean age, 64 years ± 19 [standard deviation], 2669 male) were included. With final diagnosis as the reference, 2564 of the 4824 patients had COVID-19 (53%). Sensitivity, specificity, negative predictive value, and positive predictive value of chest CT in the diagnosis of COVID-19 were 2319 of 2564 (90%; 95% CI: 89, 91), 2056 of 2260 (91%; 95% CI: 91, 92), 2056 of 2300 (89%; 95% CI: 87, 90), and 2319 of 2524 (92%; 95% CI: 91, 93), respectively. There was no significant difference for chest CT efficacy among the 26 geographically separate sites, each with varying amounts of disease prevalence. Conclusion Use of chest CT for the initial diagnosis and triage of patients suspected of having coronavirus disease 2019 was successful. © RSNA, 2021 Online supplemental material is available for this article.

Prevalence of Thoracic Aortic Aneurysms in Patients with Degenerative Abdominal Aortic Aneurysms: Results from the Prospective ACTA Study.

OBJECTIVE: There are no recommendations for screening for thoracic aortic aneurysms (TAAs), even in patients with infrarenal abdominal aortic aneurysms (AAAs). The aims of this study were to determine the prevalence of TAAs in patients with AAAs and to analyse the risk factors for this association. METHODS: This was a multicentre prospective study. The Aortic Concomitant Thoracic and Abdominal Aneurysm (ACTA) study included 331 patients with infrarenal AAAs > 40 mm between September 2012 and May 2016. These patients were prospectively enrolled in three French academic hospitals. RESULTS: Patients were classified as having a normal, aneurysmal, or ectatic (non-normal, non-aneurysmal) thoracic aorta according to their maximum aortic diameter indexed by sex, age, and body surface area. Thoracic aortic ectasia (TAE) was defined as above or equal to the 90th percentile of normal aortic diameters according to gender and body surface area. Descending TAA was defined as ≥ 150% of the mean normal value, and ascending TAA as > 47 mm in men and 42 mm in women; 7.6% (n = 25) had either an ascending (seven cases; 2.2%) or descending aortic TAA (18 cases; 5.4%), and 54.6% (n = 181) had a TAE. Among the 25 patients with TAAs, five required surgery; two patients had TAAs related to penetrating aortic ulcers < 60 mm in diameter, and three had a TAA > 60 mm. In the multinomial regression analysis, atrial fibrillation (AF) (odds ratio [OR] 11.36, 95% confidence interval [CI] 2.18 - 59.13; p = .004) and mild aortic valvulopathy (OR 2.89, 1.04-8.05; p = .042) were independent factors associated with TAAs. Age (OR 1.06, CI 1.02 - 1.09; p = .003) and AF (OR 4.36, 1.21 - 15.61; p = .024) were independently associated with ectasia. CONCLUSION: This study confirmed that TAAs coexisting with AAAs are not rare, and one fifth of these TAAs are treated surgically. Systematic screening by imaging the whole aorta in patients with AAAs is clinically relevant and should lead to an effective prevention policy.

Combining Volumetric and Wall Shear Stress Analysis from CT to Assess Risk of Abdominal Aortic Aneurysm Progression.

Background Despite known limitations, the decision to operate on abdominal aortic aneurysm (AAA) is primarily on the basis of measurement of maximal aneurysm diameter. Purpose To identify volumetric and computational fluid dynamics parameters to predict AAAs that are likely to progress in size. Materials and Methods This study, part of a multicenter prospective registry (NCT01599533), included 126 patients with AAA. Patients were sorted into stable (≤10-mL increase in aneurysm volume) and progression (>10-mL increase in aneurysm volume) groups. Initial AAA characteristics of the derivation cohort were analyzed (maximal diameter and surface, thrombus and lumen volumes, maximal wall pressure, and wall shear stress [WSS]) to identify relevant parameters for a logistic regression model. Model and maximal diameter diagnostic performances were assessed in both cohorts and for AAAs smaller than 50 mm by using area under the receiver operating characteristic curve (AUC). Results Eighty-one patients were included (mean age, 73 years ± 7 years [standard deviation]; 78 men). The derivation and validation cohorts included, respectively, 50 and 31 participants. In the derivation cohort, there was higher mean lumen volume and lower mean WSS in the progression group compared with the stable group (60 mL ± 14 vs 46 mL ± 18 [P = .005] and 66% ± 6 vs 53% ± 9 [P = .02], respectively). Mean lumen volume and mean WSS at baseline were correlated to total volume growth (r = 0.47 [P = .002] and -0.42 [P = .006], respectively). In the derivation cohort, a regression model including lumen volume and WSS to predict aneurysm enlargement was superior to maximal diameter alone (AUC, 0.78 vs 0.52, respectively; P = .003); although no difference was found in the validation cohort (AUC, 0.79 vs 0.71, respectively; P = .51). For AAAs smaller than 50 mm, a regression model that included both baseline WSS and lumen volume performed better than maximal diameter (AUC, 0.79 vs 0.53, respectively; P = .01). Conclusion Combined analysis of lumen volume and wall shear stress was associated with enlargement of abdominal aortic aneurysms at 1 year, particularly in aneurysms smaller than 50 mm in diameter. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Mitsouras and Leach in this issue.

COVID-19 impact assessment on the French radiological centers: a nationwide survey.

PURPOSE: To determine the impact of the COVID-19 on the CT activities in French radiological centers during the epidemic peak. MATERIALS AND METHODS: A cross-sectional prospective CT scan survey was conducted between March 16 and April 12, 2020, in accordance with the local IRB. Seven hundred nine radiology centers were invited to participate in a weekly online survey. Numbers of CT examinations related to COVID-19 including at least chest (CTcovid) and whole chest CT scan activities (CTchest) were recorded each week. A sub-analysis on French departments was performed during the 4 weeks of the study. The impact of the number of RT-PCRs (reverse transcriptase polymerase chain reactions) on the CT workflow was tested using two-sample t test and Pearson's test. RESULTS: Five hundred seventy-seven structures finally registered (78%) with mean response numbers of 336 ± 18.9 (323; 351). Mean CTchest activity per radiologic structure ranged from 75.8 ± 133 (0-1444) on week 12 to 99.3 ± 138.6 (0-1147) on week 13. Mean ratio of CTcovid on CTchest varied from 0.36 to 0.59 on week 12 and week 14 respectively. There was a significant relationship between the number of RT-PCR performed and the number of CTcovid (r = 0.73, p = 3.10-16) but no link with the number of positive RT-PCR results. CONCLUSION: In case of local high density COVID-19, CT workflow is strongly modified and redirected to the management of these specific patients. KEY POINTS: • Over the 4-week survey period, 117,686 chest CT (CTtotal) were performed among the responding centers, including 61,784 (52%) CT performed for COVID-19 (CTcovid). • Across the country, the ratio CTcovid/CTtotal varied from 0.36 to 0.59 and depended significantly on the local epidemic density (p = 0.003). • In clinical practice, in a context of growing epidemic, in France, chest CT was used as a surrogate to RT-PCR for patient triage.

Embolization of the Superior Rectal Arteries for Hemorrhoidal Disease: Prospective Results in 25 Patients.

PURPOSE: To evaluate efficacy and safety of superior rectal artery embolization of hemorrhoidal disease as a first-line invasive treatment. MATERIALS AND METHODS: This prospective study was conducted between 2014 and 2015 on 25 consecutive patients (16 men and 9 women with a mean age of 53 y [range, 30-76 y]) with grade II-III hemorrhoids refractory to medical treatment. A transfemoral superselective superior rectal artery branch embolization was performed using 2- and 3-mm diameter microcoils. Over the following 12 months, clinical outcomes were evaluated using the French bleeding score, Goligher prolapse score, visual analog scale (VAS) score for pain, quality-of-life score. The primary endpoint was relief of symptoms by 12 months based on a 2-point minimum improvement on VAS score and bleeding score. RESULTS: At 12 months after embolization, clinical success was obtained in 18 patients (72%), 8 of whom had 2 embolizations. VAS score decreased from 4.6 to 2.3 (P < .01), and bleeding score decreased from 5.5 to 2.3 (P < .01). Quality-of-life and prolapse scores also showed improvement (P < .05), and no patients experienced any early or late complications. Complete clinical failure was observed in 7 patients. After coil embolization, the collateral supply to the hemorrhoidal cushions was significantly related to any recurrence (P = .001). CONCLUSIONS: Hemorrhoidal artery coil embolization was found to be a safe and effective treatment for grade II-III hemorrhoids.

Outcomes of Pulmonary Artery Embolization and Stent Graft Placement for the Treatment of Hemoptysis Caused by Lung Tumors.

PURPOSE: To evaluate the safety and efficacy of endovascular management of pulmonary artery lesions caused by lung tumors. MATERIALS AND METHODS: Nineteen patients (15 men, 4 women; average age: 60.3 years, range, 51-86 years) treated for massive or recurrent hemoptysis with transarterial pulmonary artery embolization between 2010 and 2016 were included in this multicenter, retrospective study. Inclusion criteria were: patients with lung cancer and at least 1 episode of hemoptysis with a pulmonary artery lesion detected by computed tomography (CT) angiography or after failed bronchial artery embolization. No patient undergoing pulmonary embolization for a lung tumor was excluded. Technical success, clinical success, and complications were recorded. The survival curve was estimated using the Kaplan-Meier method RESULTS: Mean follow-up was 188.1 days (range, 0-1440 days). Primary and assisted technical success rates were 73.7% (14/19) and 84.2% (16/19), respectively. Two patients died during the procedure due to massive hemoptysis and cardiac arrest, and 1 patient was treated with surgery. All patients with technical success achieved clinical success without further bleeding. No complications were noted, and no pulmonary infarction was detected on CT scan during follow-up. Survival rates after embolization at 1 and 3 months were 67% (95% confidence interval [CI]: 40%-90%) and 46% (95% CI: 23%-80%), respectively, with 36.8% (n = 7) of the patients still alive at the end of the study. CONCLUSIONS: Embolization is an effective and safe treatment of lung tumors with pulmonary arterial bleeding.

Role of dual-energy computed tomography in detecting early recurrences of lung tumours treated with radiofrequency ablation.

PURPOSE: Detecting a recurrence after lung radiofrequency ablation (RFA) is based on a group of arguments that include CT, positron emission tomography (PET-CT) at 3 months and clinical patient follow-up. There is no one examination that is absolutely reliable. Recurrences are diagnosed tardily, when the cancers are locally extended, or when the patients are metastatic. The purpose of this article is to investigate the utility of dual-energy computed tomography (DECT) in order to assess therapeutic responses to RFA for lung neoplasia. MATERIALS AND METHODS: This institutional review board-approved study enroled 70 patients with lung tumours who underwent DECT after RFA. All patients provided a written informed consent for the study. RESULTS: The study included 70 consecutive patients, and 191 DECT measures were performed. We collected the enhancement values of all scars without establishing a prior threshold of positivity. The optimal threshold value areas appeared to be located between 20 and 35 Hounsfield unit (HU) with sensitivity between 70% and 82%; specificity between 72% and 90%; a negative predictive value (NPV) between 96% and 97% and a diagnostic accuracy index between 73% and 87%. At the one month follow-up, 53 nodules were analysed with DECT and four nodules had recurred, all of which were detected by DECT. The sensitivity, which was calculated at 100%, was excellent; the NPV was at 100% (CI: 91.62, 100) and the specificity was at 85.71% (CI: 73.33, 92.9). The diagnostic accuracy index was 86.79% (CI: 75.16, 93.45) and the average DECT acquisitions dosimetry was 106 mGy.cm (33mGy.cm 245mGy.cm). CONCLUSION: DECT could be a conceivable alternative for detecting early recurrence after lung RFA. Key points After lung RFA, a PET CT has a high rate of false positives in the initial phase; The study of enhancement in the follow-up of lung lesions treated with RFA, and especially by DECT, can be relevant; Dual Energy CT has a good efficiency for a threshold between 20 and 35 HU, especially in the first month after RFA; DECT could be a conceivable alternative for detecting early recurrence.

Persistent pathways after lung radiofrequency ablation as a risk factor of drain placement.

PURPOSE: The risk factors of pneumothorax after lung radiofrequency (RF) ablation are long known. The objective was to demonstrate that the visualisation of an aeric RF path after the needle withdrawal was predictive of pneumothorax occurrence and chest tube placement. MATERIALS AND METHODS: A total of 70 patients were retrospectively included in this study. For each patient, we determined the pneumothorax risk factors (age, gender, previous surgery, emphysema, lesion size, distance between pleura and lesion), visualisation of a RF track, length and thickness, presence of pneumothorax, volume, chest tube placement, duration of drainage and hospital stay. RESULTS: Among 70 patients included retrospectively, 26 needed a chest tube placement (37%). Considering the group with path visualisation (37 patients, group A) and the patients without path visualisation (group B), the 2 groups were comparable for pneumothorax risk factors. Considering the patients who needed a chest drain, the visualisation of the path was significatively more important (23 cases, 88.4%) (p< 10-3) than in the group without (8 patients, 31.8%). Multivariate analyses were significant in the three analyses after adjustments on the risk factors for the occurrence of pneumothorax. Incidence of drains was significantly more (p < 10-3) important in group A (23 drainages 62%) than in group B (4 drainages or 12%). The length and thickness of the tracks were not predictable of drain placement. CONCLUSIONS: Besides the well-known risk factors of severe pneumothorax after lung RFA, the simple visualisation of an aeric path just after the RF needle withdrawal is significantly associated with chest tube placement and can be considered as a risk factor as itself.

Pathological effects of lung radiofrequency ablation that contribute to pneumothorax, using a porcine model.

OBJECTIVES: The incidence of pneumothorax is 7 times higher after lung radiofrequency ablation (RFA) than after lung biopsy. The reasons for such a difference have never been objectified. The histopathologic changes in lung tissue are well-studied and established for RF in the ablation zone. However, it has not been previously described what the nature of thermal injury might be along the shaft of the RF electrode as it traverses through normal lung tissue to reach the ablation zone. The purpose of this study was to determine the changes occurring around the RF needle along the pathway between the ablated zone and the pleura. MATERIAL AND METHODS: In 3 anaesthetised and ventilated swine, 6 RFA procedures (right and left lungs) were performed using a 14-gauge unipolar multi-tined retractable 3 cm radiofrequency LeVeen probe with a coaxial introducer positioned under CT fluoroscopic guidance. In compliance with literature guidelines, we implemented a gradually increasing thermo-ablation protocol using a RF generator. Helical CT images were acquired pre- and post-RFA procedure to detect and evaluate pneumothorax. Four percutaneous 19-gauge lung biopsies were also performed on the fourth swine under CT guidance. Swine were sacrificed for lung ex vivo examinations, scanning electron microscopy (SEM) and pathological analysis. RESULTS: Three severe (over 50 ml) pneumothorax were detected after RFA. In each one of them, pathological examination revealed a fistulous tract between ablation zone and pleura. No fistulous tract was observed after biopsies. In the 3 cases of severe pneumothorax, the tract was wide open and clearly visible on post procedure CT images and SEM examinations. The RFA tract differed from the needle biopsy tract. The histological changes that are usually found in the ablated zone were observed in the RFA tract's wall and were related to thermal lesions. These modifications caused the creation of a coagulated pulmonary parenchyma rim between the thermo-ablation zone and the pleural space. The structural properties of the damage can explain why the RFA tract is remains patent after needle withdrawal. CONCLUSION: Our study demonstrates for the first time that the changes around the RF needle are the same as in the ablated zone. The damage could create fistulous tracts along the needle path between thermo-ablation zone and pleural space. These fistulas could certainly be responsible for severe pneumothorax that occurs in many patients treated with lung RFA.

Embolisation of pulmonary radio frequency pathway - a randomised trial.

PURPOSE: Pneumothorax is the most common complication following a pulmonary percutaneous radiofrequency ablation (RFA), and thoracic drainages are the most frequent causes of an extended hospital stay. Our main objective was to show that the use of gelatin torpedoes may significantly decrease the number of chest tube placement. MATERIALS AND METHODS: Seventy-three patients were prospectively included in this study and then randomised into two groups: 34 with embolisation and without 39 without embolisation. Each group was comparable for different pneumothorax risk factors. RESULTS: There were 16 (47%) pneumothorax in Group A ("with embolisation"), which was significantly lower (p < .0001) than the 35 pneumothorax (90%) in Group B ("without embolisation"). The pneumothorax volume (p = .02) was significantly lower in Group A (22.7% average, standard deviation 15.6%) than in Group B (average 34.1%, standard deviation 17.1%). The number of drainages was significantly smaller in those with embolisation (3 drainages or 8%) than those without embolisation (25 drainages or 64%) (p < .001). CONCLUSION: When using absorbable gelatin torpedoes, pulmonary RFA pathways embolisation significantly decreased the number of pneumothorax and thoracic drainages to the advantage of therapeutic abstention and exsufflation, non-invasive and functional operational techniques.

Young Women with a Long Past of Resistant Hypertension Cured after Surgery of Severe Bilateral Ostial Renal Artery Stenosis.

Fibromuscular dysplasia (FMD) is an underdiagnosed disease which can affect young people and with poor prognosis such as dissection or aneurysm rupture if unknown. This case illustrates a multi-vessel FMD with symptomatic severe bilateral ostial renal artery stenosis and intracranial aneurysms. One of the original features is a very late delay to diagnosis with 23 years between onset of hypertension and renal stenosis diagnosis, particularly due to lower quality of initial CT scan with milder and uncommon abnormalities. The experiment neuroradiologist had suspected the diagnosis of renal FMD because she developed intracranial aneurysms and he confirmed this diagnosis with an artery renal contrast injection during an intracranial angiogram Because of very tight and short stenosis, surgery was chosen for treatment and permitted the cure of hypertension, with normal home blood pressure after 6 months. Several particularities of FMD were presented in this case: important delay diagnosis due to rare lesion and lower sensitivity of CT in this form, the possibility to perform an angiography in high suspicion of FMD, poor prognosis risk with intracranial aneurisms and premature birth child, and the choice for surgery with cure of hypertension. We thought that hypertension etiologic evaluation must be repeated in case of resistant hypertension in young patients, particularly when they developed intracranial aneurysms.

Intranuclear expression of progesterone receptors in smooth muscle cells of renovascular fibromuscular dysplasia: a pilot study.

BACKGROUND: The pathogenesis of fibromuscular dysplasia (FMD) remains poorly understood. Yet, understanding this mechanism has taken on new urgency after recent evidence indicating that FMD is not as rare as previously thought. We speculated that hormonal receptors in the walls of dysplastic renal arteries were implicated in the pathogenesis of FMD. METHODS: We undertook a pilot prospective case-control study comparing histologic findings from renal arteries that were surgically removed in 2 patient groups. The case group included 6 samples from FMD patients who underwent surgery for stenosis or aneurysm caused by FMD. The control group included 3 FMD-free patients who underwent nephrectomy for nonvascular causes. Surgical specimens were sent to the histology laboratory. FMD was defined preoperatively using conventional radiologic criteria and was confirmed by histologic examination. RESULTS: Immunohistochemical staining detected intense progesterone receptor expression in the nuclei of smooth muscle cells in FMD patients. No progesterone receptor expression was found in the FMD-free patients. Estrogen receptor expression was not noted in the 2 groups. CONCLUSIONS: This preliminary finding may suggest that progesterone plays a key role in the pathogenesis of FMD and opens the fields of genetic and therapeutic approaches.

An updated classification of the anatomical variations of the internal iliac venous drainage system: Surgical implications for anterior lumbar spinal approaches.

BACKGROUND: Advanced pelvic surgery is associated with potential vascular risks. The aim of this study was to complete the existing classification of the anatomical variations of the internal iliac veins encountered on a series of preoperative angio CT with a view to performing anterior lumbar spine surgery. MATERIALS AND METHODS: In this monocentric retrospective study conducted between 2010 and 2020, all preoperative angio CT performed before an anterior lumbar surgery were systematically analyzed. All the abnormalities of the iliac veins were referenced in an updated classification system. RESULTS: 910 patients (431 men and 479 women) with a mean age of 49 years [16-88] were included. Apart from the most common variant in the population (type I), 64 anatomical variations (7.0%) in the iliac veins were reported and classified according to our new classification. The percentage of coverage of the L4-L5 intervertebral disc is 52%, including 32% by the inferior vena cava before the confluence of the common iliac veins. At the level of the L5-S1 intervertebral disc, the coverage is 30% (same distribution between left and right). CONCLUSIONS: Variations of the iliac veins are frequent, and contrary to what one might think, and even if they can represent an anatomical trap during surgery, certain variations do not limit anterior lumbar spine surgery and are not more associated with vascular complications. Nevertheless, these anatomical variations must be known before any advanced pelvic surgery. Depending on their distribution, level L5-S1 is more suitable for ALIF, level L4-L5 for OLIF approaches.

Incidence, predictors, and prognostic value of intramyocardial hemorrhage lesions in ST elevation myocardial infarction.

BACKGROUND: Intra myocardial hemorrhage lesions (IMH) are underdiagnosed complication of ST elevation myocardial infarction (STEMI). We sought to determine the incidence, predictors and the prognostic value of IMH in STEMI using cardiac MR imaging (CMR) techniques. METHODS: We screened for inclusion consecutive patients with STEMI treated by percutaneous coronary intervention (PCI) within the first 12 hr of evolution. IMH lesions were identified on T2-weighted sequences on CMR between days 4 and 8 after PCI. Adverse cardiac events were defined as a composite of death + severe ventricular arrhythmias + acute coronary syndrome + acute heart failure. RESULTS: N = 114 patients were included and n = 11 patients (10%) presented IMH lesions. Patients with IMH lesions had a larger myocardial infarction extent (25.6 ± 1.8 vs. 13.5 ± 1.0 % LV mass, P < 0.01), microvascular obstructive lesions extent (4.6 ± 1.0 vs. 1.3 ± 0.3% LV mass, P < 0.01) and lower LV ejection fraction (40.7 ± 2.3% vs. 50.7 ± 1.3%, P < 0.01). The value of glycemia at admission was an independent predictor of IMH development (Odd ratio 1.8 [1.1-2.8] per mmol l(-1), P = 0.01). The incidence of adverse cardiac events was higher in the IMH group than in the non-IMH group during the first year following STEMI (P = 0.01, log-rank analysis). Cox regression analysis identified the presence of IMH lesions as an independent predictor of adverse clinical outcome (Hazard Ratio = 2.8 [1.2-6.8], P = 0.02). CONCLUSION: Our study indicates that IMH is a rare but severe finding in STEMI, associated with a larger myocardial infarction and a worse clinical outcome. Per-PCI glycemia might influence IMH development.

French Imaging Database Against Coronavirus (FIDAC): A large COVID-19 multi-center chest CT database.

PURPOSE: During the first wave of the COVID-19 pandemic, the French Society of Radiology and the French College of Radiology, in partnership with NEHS Digital, have set up a system to collect chest computed tomography (CT) examinations with clinical, virological and radiological metadata, from patients clinically suspected of COVID-19 pneumonia. This allowed the constitution of an anonymized multicenter database, named FIDAC (French Imaging Database Against Coronavirus). The aim of this report was to describe the content of this public database. MATERIALS AND METHODS: Twenty-two French radiology centers participated to the data collection. The data collected were chest CT examinations in DICOM format associated with the following metadata: patient age and sex, originating facility identifier, originating facility region, time from symptom onset to CT examination, indication for CT examination, reverse transcription-polymerase chain reaction (RT-PCR) results and normalized CT report performed by a senior radiologist. All the data were anonymized and sent through a NEHS Digital system to a centralized data center. RESULTS: A total of 5944 patients were included from the 22 centers aggregated into 8 regions with a mean number of patients of 743 ± 603.3 [SD] per region (range: 102-1577 patients). Reasons for CT examination and normalized CT reports were provided for all patients. RT-PCR results were provided in 5574 patients (93.77%) with a positive result of RT-PCR in 44.6% of patients. CONCLUSION: The FIDAC project allowed the creation of a large database of chest CT images and metadata available, under conditions, in open access through the CERF-SFR website.

Congenital anomalies of inferior vena cava in young patients with iliac deep venous thrombosis.

Venous thromboembolism (VTE) in young patients is frequently associated with hereditary biological thrombophilia, autoimmune disorders, or neoplasia. Advances in venous ultrasound and contrast-enhanced computed tomography have allowed for the identification of inferior vena cava (IVC) anomalies as newly considered etiologic factor. We present two cases of VTE in young patients: the first case involves left IVC in a 22-year-old man and the second involves IVC atresia in a 39-year-old man. IVC anomalies should be identified in young patients with spontaneous VTE involving the iliac veins because they are at a high risk for thrombotic recurrence and adaptation to long periods of antithrombotic therapy.

Measurement of trabeculated left ventricular mass using cardiac magnetic resonance imaging in the diagnosis of left ventricular non-compaction.

AIMS: To describe a method for measuring trabeculated left ventricular (LV) mass using cardiac magnetic resonance imaging and to assess its value in the diagnosis of left ventricular non-compaction (LVNC). METHODS AND RESULTS: Between January 2003 and 2008, we prospectively included 16 patients with LVNC. During the mean period, we included 16 patients with dilated cardiomyopathy (DCM), 16 patients with hypertrophic cardiomyopathy (HCM), and 16 control subjects. Left ventricular volumes, LV ejection fraction, and trabeculated LV mass were measured in the four different populations. The percentage of trabeculated LV mass was almost three times higher in the patients with LVNC (32 +/- 10%), compared with those with DCM (11 +/- 4%, P < 0.0001), HCM (12 +/- 4%, P < 0.0001), and controls (12 +/- 5%, P < 0.0001). A value of trabeculated LV mass above 20% of the global mass of the LV predicted the diagnosis of LVNC with a sensitivity of 93.7% [95% confidence interval (CI), 71.6-98.8%] and a specificity of 93.7% (95% CI, 83.1-97.8%; kappa = 0.84). CONCLUSION: The method described is reproducible and provides an assessment of the global amount of LV trabeculation. A trabeculated LV mass above 20% of the global LV mass is highly sensitive and specific for the diagnosis of LVNC.

Effectiveness of endovascular embolization with a collagen-based embolic agent (Marsembol) in an animal model.

PURPOSE: To investigate in a porcine experimental model the effectiveness, tissue penetration, and histologic impact of renal artery embolization with a collagen-based nonadhesive embolic agent, marsembol. MATERIALS AND METHODS: Fifteen pigs underwent embolization of one interlobular artery of the renal artery with collagen-resorcinol gel emulsified with Lipiodol and further polymerized with glutaraldehyde-formaldehyde mixture. Angiograms were obtained before, during, and after the procedure. Animals were euthanized at day 0 (n = 3), 1 week (n = 3), or 3 months (n = 7), and flat-panel three-dimensional rotational radiologic images of the kidneys were obtained. Arterial, medullary, and cortical samples were taken for histologic and scanning electron microscopic investigations. RESULTS: Fifteen interlobular renal arteries were successfully embolized by delivering 1.7 mL + or - 0.2 of the embolic agent. All the embolized arteries remained occluded at 3 months, leading to a major atrophy of the embolized portions of the kidneys. Imaging and histologic findings show that the embolic agent provided a distal vessel occlusion and entirely filled the lumen of the arteries up to the glomerular tufts. The homogeneous plug formed by the embolic agent induces very few inflammatory responses. The regenerative tubular processes were arrested at 3 months. CONCLUSIONS: The collagen-based embolic agent described here has the properties required to perform embolization. These specific properties lead to very distal vessel embolization. The embolic agent is effective at 3 months in renal embolization.

Accessory iliac vein: surgical implications.

BACKGROUND: One of the main difficulties in using an anterior retroperitoneal approach in prosthetic lumbar disk replacement surgery is the exposure of the anterior aspect of the spine because of the risk of hemorrhage because of vascular injury when the venous structures are mobilized. PURPOSE: The goal of our study was to use computed tomography (CT) to research for anatomic variations of the ileocaval drainage network, which were likely to complicate this type of procedure. DESIGN: Prospective study. PATIENT SAMPLE: Ninety patients (48 males, 42 females) explored between July 2003 and February 2007. OUTCOME MEASURES: Not applicable. METHODS: All the patients had a CT scan before disk replacement surgery to treat degenerative lumbar disk disease by a microinvasive, anterior retroperitoneal approach. RESULTS: Eighteen of 90 patients presented with variations in their iliocaval drainage network: 3 cases of double inferior vena cava, 1 case of duplication of the inferior vena cava, 5 cases of ectopic internal iliac veins, 9 cases of accessory iliac veins. CONCLUSIONS: Anatomical variations in the iliocaval venous drainage system are fairly frequent but easy to analyze by CT. Even if they have no functional impact, they must be analyzed and described because they can be of great interest in the preoperative workup for retroperitoneal lumbar surgery.