Rivaroxaban versus no anticoagulation for post-discharge thromboprophylaxis after hospitalisation for COVID-19 (MICHELLE): an open-label, multicentre, randomised, controlled trial.

BACKGROUND: Patients hospitalised with COVID-19 are at risk for thrombotic events after discharge; the role of extended thromboprophylaxis in this population is unknown. METHODS: In this open-label, multicentre, randomised trial conducted at 14 centres in Brazil, patients hospitalised with COVID-19 at increased risk for venous thromboembolism (International Medical Prevention Registry on Venous Thromboembolism [IMPROVE] venous thromboembolism [VTE] score of ≥4 or 2-3 with a D-dimer >500 ng/mL) were randomly assigned (1:1) to receive, at hospital discharge, rivaroxaban 10 mg/day or no anticoagulation for 35 days. The primary efficacy outcome in an intention-to-treat analysis was a composite of symptomatic or fatal venous thromboembolism, asymptomatic venous thromboembolism on bilateral lower-limb venous ultrasound and CT pulmonary angiogram, symptomatic arterial thromboembolism, and cardiovascular death at day 35. Adjudication was blinded. The primary safety outcome was major bleeding. The primary and safety analyses were carried out in the intention-to-treat population. This trial is registered at ClinicalTrials.gov, NCT04662684. FINDINGS: From Oct 8, 2020, to June 29, 2021, 997 patients were screened. Of these patients, 677 did not meet eligibility criteria; the remaining 320 patients were enrolled and randomly assigned to receive rivaroxaban (n=160 [50%]) or no anticoagulation (n=160 [50%]). All patients received thromboprophylaxis with standard doses of heparin during hospitalisation. 165 (52%) patients were in the intensive care unit while hospitalised. 197 (62%) patients had an IMPROVE score of 2-3 and elevated D-dimer levels and 121 (38%) had a score of 4 or more. Two patients (one in each group) were lost to follow-up due to withdrawal of consent and not included in the intention-to-treat primary analysis. The primary efficacy outcome occurred in five (3%) of 159 patients assigned to rivaroxaban and 15 (9%) of 159 patients assigned to no anticoagulation (relative risk 0·33, 95% CI 0·12-0·90; p=0·0293). No major bleeding occurred in either study group. Allergic reactions occurred in two (1%) patients in the rivaroxaban group. INTERPRETATION: In patients at high risk discharged after hospitalisation due to COVID-19, thromboprophylaxis with rivaroxaban 10 mg/day for 35 days improved clinical outcomes compared with no extended thromboprophylaxis. FUNDING: Bayer.

Radiological Profile of 18,430 Vascular Anomalies: Incidence and Demographic Distribution in an Adult Population.

BACKGROUND: Most studies on focusing on the prevalence of vascular anomalies are either aimed to determine the individual occurrence of a specific type among known bearers of abnormalities or propose an estimation of prevalence for the general population by extrapolating from the paediatric population. In this scenario, we intended to assess the profile of vascular anomalies in a group of patients subjected to imaging studies, throughout a long period of time, to evaluate the frequency of abnormal findings in a consecutive, nonselected population. METHODS: This is a retrospective review of 996,569 computed tomography and magnetic resonance studies between 2009 and 2019. Findings were grouped as vascular tumours (hemangiomas; vascular tumours), cavernomas, and vascular malformations. Positive findings were evaluated with regard to patients' demographic characteristics and anatomic distribution and the subset of vascular malformations was also evaluated with regard to size, classification in accordance to flow pattern, and Hamburg Classification. RESULTS: Eighteen thousand four hundred thirty positive examinations were evaluated (mean age, 55.82 ± 15.43 years; 8,188 men). Vascular anomalies were present in 18.49 per 1,000 examinations (17.41 hemangiomas; 0.69 cavernomas and 0.39 vascular malformations per 1,000 examinations). Hemangiomas and cavernomas were homogeneous in anatomic location between sexes throughout the age groups. Complex malformations were heterogeneous in anatomic distribution between the sexes in each age group, with intracranial findings decreasing for female patients in older groups. CONCLUSIONS: Vascular anomalies were found in 18.49 per 1,000 examinations. Hemangiomas and cavernomas were homogenously distributed, whereas complex malformations displayed a heterogeneous anatomic distribution pattern between sexes in each age group.

Medically Ill hospitalized Patients for COVID-19 THrombosis Extended ProphyLaxis with rivaroxaban ThErapy: Rationale and Design of the MICHELLE Trial.

BACKGROUND: The devastating Coronavirus disease (COVID-19) pandemic is associated with a high prothrombotic state. It is unclear if the coagulation abnormalities occur because of the direct effect of SARS-CoV-2 or indirectly by the cytokine storm and endothelial damage or by a combination of mechanisms. There is a clear indication of in-hospital pharmacological thromboprophylaxis for every patient with COVID-19 after bleed risk assessment. However, there is much debate regarding the best dosage regimen, and there is no consensus on the role of extended thromboprophylaxis. DESIGN: This study aims to evaluate the safety and efficacy of rivaroxaban 10 mg once daily for 35 ± 4 days versus no intervention after hospital discharge in COVID-19 patients who were at increased risk for VTE and have received standard parenteral VTE prophylaxis during hospitalization. The composite efficacy endpoint is a combination of symptomatic VTE, VTE-related death, VTE detected by bilateral lower limbs venous duplex scan and computed tomography pulmonary angiogram on day 35 ± 4 posthospital discharge and symptomatic arterial thromboembolism (myocardial infarction, nonhemorrhagic stroke, major adverse limb events, and cardiovascular death) up to day 35 ± 4 posthospital discharge. The key safety outcome is the incidence of major bleeding according to ISTH criteria. SUMMARY: The MICHELLE trial is expected to provide high-quality evidence around the role of extended thromboprophylaxis in COVID-19 and will help guide medical decisions in clinical practice.1.

Prevalence, growth rate and complications of splenic artery aneurysms in chronic liver disease patients.

Background: Chronic liver disease (CLD) patients are at greater risk for developing splenic artery aneurysm (SAA). Treatment for aneurysms > 2.5 cm in this population is considered. However, the procedure might be challenging in CLD patients, and complications may interfere in liver transplantation. We, therefore, sought to estimate the prevalence, growth rate and complications of SAA in patients with CLD. As secondary objective, we sought to evaluate whether those features differ in pre and post transplantation follow-up and among aneurysms with diameters greater or less than 2.5 cm at diagnosis. Patients and methods: We searched for the terms "SAA" and "CLD" on CT or MRI reports from January 2009 to December 2016. Patients with single examination or less than 6 months follow-up were excluded. Results: Fifty nine out of 2050 CLD patients presented SAA (prevalence of 2.9%). Fifteen patients were excluded (due to exclusion criteria). Forty-four CLD patients (mean age 55.9 years) presented 76 SAA (follow-up median of 27.2 months). Aneurysms presented mean size of 1.5 ± 0.74 cm at diagnosis and growth rate of 0.12 ± 0.14 cm/y. Two (4.5%) patients presented mild complications (aneurysm thrombosis). No significant differences were observed in the growth rates of aneurysms < 2.5 cm and ≥ 2.5 cm or in the initial size and growth rates of aneurysms of patients submitted to and not submitted to liver transplantation. Conclusions: The estimated prevalence of SAA in patients with DLC in the Brazilian population is 2.9% (CI95% 2.2-3.6%). Although SAA in CLD patients are less likely to remain stable and grow faster than in general population, aneurysms are usually diagnosed at smaller size and complications are rare. These findings might support conservative management with close surveillance, especially in smaller aneurysms.

Incidence, diagnosis, treatment methods, and outcomes of clinically suspected venous thromboembolic disease in patients with COVID-19 in a quaternary hospital in Brazil.

BACKGROUND: Prothrombotic states have been associated with viral infections and the novel Sars-COV-2 infection has been associated with elevated D-dimer levels, although no causal relation has been clearly established. OBJECTIVES: This study presents an epidemiological analysis of manifest VTE episodes in a group of patients hospitalized because of COVID-19. METHODS: Medical records of patients who presented symptomatic deep vein thrombosis and/or pulmonary embolism in concomitance with confirmed COVID-19 were retrospectively studied. Demographic characteristics, prevalence of VTE, site of occurrence, D-dimer variation over time, management, and outcomes were analyzed. RESULTS: During the study period, 484 confirmed cases of COVID-19 were admitted, 64 of which displayed VTE symptoms and 13 of which had confirmed symptomatic VTE(2.68% of total sample and 20.31% of symptomatic cases). Most cases (76.92%) occurred in intensive care. On the day attributed to VTE onset, D-dimer levels were over 3,000 ng/mL in 8 (80%) patients, a significant increase from baseline admission levels (p < 0.05). A significant decrease was also observed in D-dimer values at hospital discharge (p < 0.05). All patients received pharmacological thromboprophylaxis and/or anticoagulation as indicated. Two deaths occurred during the study, both patients with severe comorbidities. At the end of our study protocol, nine patients had been discharged and two remained hospitalized, but had no signs of VTE worsening. CONCLUSIONS: VTE prevalence in hospitalized COVID-19 patients was 2.7%, and higher in intensive care units. Early institution of prophylaxis and immediate full anticoagulation when VTE is diagnosed should be the goals of those who treat this kind of patient.

CONTEXTO: Os estados pró-trombóticos têm sido associados a infecções virais. A nova infecção pela síndrome respiratória aguda grave do coronavírus 2 (SARS-CoV-2) sabidamente eleva os níveis de D-dímero, embora a relação causal não tenha sido bem estabelecida. OBJETIVOS: Este estudo apresenta uma análise epidemiológica de episódios sintomáticos de tromboembolismo em um grupo de pacientes hospitalizados pela doença do novo coronavírus (COVID-19). MÉTODOS: Foi realizada uma revisão retrospectiva de prontuários de pacientes internados por COVID-19 que apresentaram trombose venosa profunda e/ou embolia pulmonar sintomáticas. Foram avaliados os dados demográficos, a prevalência de tromboembolismo, a variação do D-dímero ao longo do tempo, o manejo e os desfechos. RESULTADOS: Dos 484 casos confirmados de COVID-19 admitidos entre março e julho de 2020, 64 apresentaram sintomas de tromboembolismo, que foram investigados, e 13 tiveram tromboembolismo confirmado (2,68% do total e 20,31% dos sintomáticos). A maioria dos casos ocorreu em regime de terapia intensiva (76,92%). Houve um aumento significativo no número de pacientes com D-dímero acima de 3.000 ng/mL no dia atribuído ao diagnóstico de tromboembolismo com relação aos níveis do momento da admissão (80%, p < 0,05).Uma queda significativa de pacientes nesse limiar também foi observada no momento da alta (p < 0,05). Todos os pacientes receberam tromboprofilaxia ou anticoagulação conforme indicado. Houve dois óbitos na amostra, ambos pacientes com comorbidades severas. Ao fim do protocolo, nove pacientes receberam alta e dois permaneceram hospitalizados, mas sem sinais de piora. CONCLUSÕES: A prevalência de tromboembolismo em pacientes hospitalizados por COVID-19 foi de 2,7%, sendo mais frequente em regime de terapia intensiva. A instituição precoce de profilaxia e anticoagulação imediata ao diagnóstico é primordial nesse grupo de pacientes.

Interobserver agreement of PI-RADS v. 2 lexicon among radiologists with different levels of experience.

BACKGROUND: Evaluation of interobserver agreement of the PI-RADS v2 lexicon is important to validate the uniformity of this widely used classification. PURPOSE: To determine the interobserver agreement of PI-RADS v2 lexicon among eight radiologists with varying levels of experience. STUDY TYPE: Retrospective. POPULATION: In all, 160 consecutively imaged men with confirmatory targeted biopsy. FIELD STRENGTH/SEQUENCE: 3T scanner without an endorectal coil. T2 -weighted imaging (T2 w), diffusion-weighted imaging (DWI), apparent diffusion coefficient (ADC) map and dynamic contrast-enhanced sequence were performed. ASSESSMENT: Eight radiologists (two highly experienced, two moderately experienced, and four less experienced) independently read 130 lesions in the peripheral zone (PZ) and 30 lesions in the transition zone (TZ), blinded to clinical MRI indication and biopsy results. The features described in PI-RADS v2 for TZ and PZ lesions were evaluated. STATISTICAL TESTS: Conger's kappa, percentage of concordance, and first-order agreement coefficient (AC1) were used to evaluate interobserver agreement. RESULTS: From the features evaluated on PZ lesions, definite extraprostatic extension (EPE) / invasive behavior on T2 w had good agreement (AC1 = 0.80), and the others had fair agreement (AC1 = 0.32-0.40). From the features evaluated on TZ lesions, two had good agreement: definite EPE/invasive behavior (AC1 = 0.77) and moderate/marked hypointensity (AC1 = 0.67) on T2 w. Encapsulation and lenticular shape on T2 w, focal (not indistinct) on DWI and ADC map, and marked hypointensity on ADC map (AC1 = 0.45 to 0.60) had moderate agreement, whereas heterogeneous and circumscribed (not obscured margins) on T2 w, marked hyperintensity on high-b-value DWI, and the presence or not of early enhancement in the lesion/region of the lesion (AC1 = 0.30 to 0.38) had fair agreement. DATA CONCLUSION: Interobserver agreement in PI-RADS v2 lexicon ranges from fair to good among radiologists and improves with increasing experience. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2020;51:593-602.

Magnetic Resonance Imaging Evaluation of Left Common Iliac Vein Compression in Patients With and Without Symptoms of Venous Disease.

BACKGROUND: The goal of this study was to assess the degree of the left common iliac vein (LCIV) compression by the right common iliac artery (RCIA) on magnetic resonance imaging (MRI), and verify differences in compression measurements in end-inspiration, end-expiration, supine, and prone decubitus between patients with and without symptoms in the lower limbs.Methods and Results:A total of 82 consecutive participants provided informed consent and underwent pelvic MRI for different clinical indications other than vascular-related disorders. The participants answered a questionnaire about venous disease in the lower limbs and history of previous deep vein thrombosis. This study measured the area and diameter of the LCIV at the site of the crossing with the RCIA and in the uncompressed caudal LCIV segment. Statistical analysis was performed to compare the degree of LCIV compression by the RCIA and verify differences in compression measurements. A total of 71 participants were included; 46.6% were in group A and did not experience signs and symptoms in lower limbs and 53.6% were in group B and answered at least one question with a positive answer. It was observed that there was a statistically significant difference between groups for end-expiration. No statistically significant differences were observed for all other measurements. CONCLUSIONS: A substantial percentage of the asymptomatic and symptomatic population showed compression of the LCIV, suggesting there are no clear relationships between stenosis and non-specific symptomatology in the general population.

Comparison of Radiation Dose and Image Quality of Abdominopelvic CT Using Iterative (AIDR 3D) and Conventional Reconstructions.

OBJECTIVE: The purpose of this study is to compare radiation dose and image quality of abdominopelvic CT studies reconstructed with iterative and conventional techniques. MATERIALS AND METHODS: This retrospective study enrolled 99 patients who underwent abdominopelvic CT examinations with the portal venous phase images reconstructed with both filtered back projection and Adaptive Iterative Dose Reduction 3D (AIDR 3D) at different time points. Subjective assessment of image quality was performed by two radiologists who scored axial images for overall quality, sharpness, noise, and acceptability in a blinded fashion. The SD of the mean attenuation of the liver, aorta, and paraspinal muscle (as a measurement of image noise) and contrast-to-noise and signal-to-noise ratios for liver and aorta were used as objective parameters of image quality. Radiation dose parameters included CT dose index volume (CTDIvol), dose-length product, effective dose (ED), and size-specific dose estimate (SSDE). Results were compared for different body mass index (BMI; weight in kilograms divided by the square of height in meters) categories. Paired t test and McNemar paired tests for noninferiority were used, with p < 0.05 considered statistically significant. RESULTS: We obtained a 62.5% mean reduction in CTDIvol, a 58% mean reduction in ED, and a 63% mean reduction in SSDE when AIDR 3D was used (p < 0.001). Subjective parameters of image quality were considered noninferior for AIDR 3D studies compared with filtered back projection (p < 0.001), except for the sharpness of images of patients with BMI 20-24.9. Variable results were found regarding objective assessment of image quality. CONCLUSION: AIDR 3D allowed a significant reduction in radiation dose of abdominopelvic CT examinations without a loss of image quality in general.

Objective value on Apparent diffusion coefficient (ADC) map to categorize the intensity of diffusion-weighted imaging (DWI) restriction for prostate cancer detection on multiparametric prostate MRI.

PURPOSE: To identify objective and subjective criteria on multiparametric prostate MRI that can be helpful for prostate cancer detection. MATERIALS AND METHODS: Retrospective study, IRB approved, including 122 patients who had suspicious lesion on MRI and who underwent prostate biopsy with ultrasonography (US)/MRI imaging fusion. There were 60 patients with positive biopsies and 62 with negative biopsies. MRI of these patients were randomized and evaluated independently by two blinded radiologists. The following variables were analyzed in each lesion: morphology, contours, T2 signal, diffusion restriction (subjective impression and objective values), hyper-enhancement, contact with transition zone or prostatic contour, prostatic contour retraction, Likert and PIRADS classification. RESULTS: Apparent diffusion coefficient (ADC) value was the best predictor of positivity for prostate cancer, with mean value of 1.08 (SD 0.20) and 1.09 mm2/sec (SD 0.24) on negative biopsies and 0.81 (SD 0.22) and 0.84 mm2/sec (SD 0.22) on positive biopsies for readers 1 and 2, respectively (p < 0.001 in both analysis). For the others categorical variables evaluated the best AUC for reader 1 was subjective intensity of diffusion restriction (AUC of 0.74) and for reader 2 was hyper-enhancement (AUC of 0.65), all inferior comparing to the value of ADC map. Interobserver agreement ranged from 0.13 to 0.75, poor in most measurements, and good or excellent (kappa > 0.6) only in lesion size and ADC values. CONCLUSIONS: Diffusion restriction with lower ADC-values is the best parameter to predict cancer on MRI prior to biopsy. Efforts to establish an ADC cutoff value would improve cancer detection, especially for less experience reader.

Endovascular Repair of Ruptured Thoracoabdominal Aortic Aneurysm with an Off-the-shelf Endoprosthesis.

BACKGROUND: Thoracoabdominal aortic aneurysm type 3 (TAAA3) is a challenging disease to vascular surgeons. In these cases, the best treatment methodology is conventional surgery, which portends a mortality rate ranging from 8% to 25%. Endovascular treatment has been shown to be a good alternative, with encouraging results. In 2012, a new alternative for endovascular treatment of TAAA3 was presented: Cook T-Branch endoprosthesis (Cook Medical, Bloomington, Indiana). We present the first successful case of endovascular treatment of a ruptured TAAA3 with this stent. CASE REPORT: A 68-year-old was admitted to the emergency department with epigastric pain, radiating to the back without improvement with opioids. Physical examination revealed an epigastric pulsatile mass without evidence of peritonitis or blows. The patient was known to have a thoracoabdominal aortic aneurysm. A computed tomography angiography showed growth of the abdominal aneurysm, accompanied with signs of rupture (fat blurring in the posterior region of TAAA3). The patient was submitted to endovascular repair of a ruptured TAAA3 in a hybrid operating room using a 34 × 18 × 202 mm T-Branch graft. It was an uneventful 330-min procedure under general anesthesia. Immediate postoperative period had no cardiovascular events. Evolution showed excellent distal perfusion and complete pain relief. CONCLUSIONS: Until now, the only endovascular alternative for ruptured aortic aneurysm was the parallel prosthesis technique. The development of an off-the-shelf T-Branch prosthesis (Cook Medical) has solved this problem in many cases, enabling immediate treatment of this type of aneurysm in approximately 83% of patients. The fact that the thoracic aorta would be excluded lead the patient to a high risk of spinal cord ischemia. We therefore decided to make a cerebrospinal fluid drainage. There is no consensus regarding the best devices to be used as branches. In this case, we chose to use the previously described covered stents, according to its flexibility and compatibility with the length of arteries. This is the first report of the use of a T-branch (Cook Medical) for treatment of a ruptured TAAA3. The development of an off-the-shelf endoprosthesis has many advantages: it is available for use in an emergency situation, and there is no time lapse for its preparation. The T-Branch stent graft is a valid option for the treatment of ruptured TAAA3.

Volumetry and biomechanical parameters detected by 3D and 2D ultrasound in patients with and without an abdominal aortic aneurysm.

The objective was to demonstrate the ability of ultrasound (US) with 3D properties to evaluate volumetry and biomechanical parameters of the aorta in patients with and without abdominal aortic aneurysm (AAA). Thirty-one patients with normal aortas (group 1), 46 patients with AAA measuring 3.0-5.5 cm (group 2) and 31 patients with AAA ⩾ 5.5 cm (group 3) underwent a 2D/3D-US examination of the infra-renal aorta, and the images were post-processed prior to being analyzed. In the maximum diameter, the global circumferential strain and the global maximum rotation assessed by 2D speckle-tracking algorithms were compared among the three groups. The volumetry data obtained using 3D-US from 40 AAA patients were compared with the volumetry data obtained by a contemporary computed tomography (CT) scan. The median global circumferential strain was 2.0% (interquartile range (IR): 1.0-3.0), 1.0% (IR: 1.0-2.0) and 1.0% (IR: 1.0-1.75) in groups 1, 2 and 3, respectively (p < 0.001). The median global maximum rotation decreased progressively from group 1 to group 3 (1.38º (IR: 0.77-2.13), 0.80º (IR: 0.57-1.0) and 0.50º (IR: 0.31-0.75), p < 0.001). AAA volume estimations by 3D-US correlated well with CT (R(2) = 0.76). In conclusion, US with 3D properties is non-invasive and has the potential to evaluate volumetry and biomechanical characteristics of AAA.

Optimized Protocol for Fast CT Angiography of Lower Limbs Using 160-Row Detector.

OBJECTIVE: We proposed and tested a novel acquisition protocol for optimizing a fast computed tomography angiography using a 160-row detector scanner using a longer contrast injection time coupled with multiphasic rate of injection. METHODS: A prospective randomized study was performed to compare image quality, contrast enhancement, and radiation dose in 2 groups (a fast acquisition and a widely accepted slow acquisition). RESULTS: There was no difference between groups regarding image quality, noise, and diagnostic performance, but we evidenced a trend to higher radiation dose for the fast acquisition protocol. CONCLUSIONS: An optimized protocol for performing a fast acquisition computed tomography angiography of lower limbs is feasible, has sufficient diagnostic quality, and can be used in selected patients who would benefit from a short-time scan.

Dynamic computed tomography angiography for noninvasive diagnosis of bow Hunter's syndrome: a case report.

The focus of this case report is to technically describe a noninvasive diagnostic evaluation of bow Hunter's syndrome using a dynamic computed tomography angiography protocol and discuss its advantages. In addition, we aimed to exemplify the quality of the study by presenting images of a 3D-printed model generated to help plan the surgical treatment for the patient. The dynamic computed tomography angiography protocol consisted of a first image acquisition with the patient in the anatomic position of the head and neck. This was followed by a second acquisition with the head and neck rotated to the side that triggered the symptoms, with technical parameters similar to the first acquisition. The acquired images were used to print a 3D model to better depict the findings for the surgical team. The dynamic computed tomography angiography protocol developed in this study helped visualize the vertebrobasilar arterial anatomy, detect vertebral artery stenosis produced by head and neck rotation, depict the structure responsible for artery stenosis (e.g., bony structure or membranes), and study possible complications of the disease (e.g., posterior cerebral circulation infarction). Additionally, the 3D-printed model better illustrated the findings of stenosis, aiding in surgical planning. In conclusion, dynamic computed tomography angiography for the evaluation of bow Hunter's syndrome is a feasible noninvasive technique that can be used as an alternative to traditional diagnostic methods.

Influence of body composition assessed by computed tomography on mortality in older adults undergoing hematopoietic stem cell transplantation.

BACKGROUND: The incidence of most hematologic malignancies increases with age. Hematopoietic stem cell transplantation (HSCT) provides a potentially life-prolonging or curative option for many patients in this scenario. Limited data assessed from computed tomography (CT) images are available on muscle mass and density outcomes after HSCT. We evaluate the influence of body composition on morbidity and mortality in older adults undergoing HSCT. METHODS: Retrospective longitudinal study conducted with 50 patients ≥ 60 years old undergoing HSCT. Body composition was assessed by chest CT (CCT), and treatment-related mortality, graft-vs-host disease (GVHD), neutrophil grafting, and overall survival were analyzed. RESULTS: 148 HSCT patients were evaluated; 50 patients were eligible: 60% with autologous and 40% with allogeneic transplantation. Body mass index in patients was (female: 26.9 ± 4.7 kg/m2 ; male: 30.1 ± 4.9 kg/m2 ) - autologous and, (female: 24.3 ± 5.1 kg/m2 ; male: 26.4 ± 2.0 kg/m2 ) - allogeneic. In the autologous group, we found a positive association between age and death risk, with 63.5% increased risk of death (P = 0.006), and also Karnofsky Performance Score, with a 11.9% decrease in death risk (P < 0.001). A negative association between muscle radiodensity and death risk was observed in patients who received an allogeneic transplantation, with a risk decrease of 20.1% (P = 0.032). We found a positive association between the fourth thoracic vertebra muscle area and radiodensity and risk of acute GVHD (P = 0.028). CONCLUSION: Body composition assessed by CCT showed the importance of radiodensity for better prognosis.

Virtual hepatectomy and metastasectomy 3D simulation using an automated and semiautomated tool applied to preoperative CT in the treatment of colorectal cancer metastases.

Colorectal cancer represents the most common malignancy of the gastrointestinal tract and the second most frequently diagnosed malignancy in adults. The most common site of metastases is the liver and 40% of patients in stage IV have liver only disease.1 Hepatic metastases are the major determinants of morbidity and mortality in these patients, with surgery being the treatment of choice or even curative in these cases.2 Therefore, aggressive surgeries should be considered in patients with liver only disease. In this context, hepatectomy and metastasectomy have emerged as promising techniques for improving survival in patients with metastatic disease, also providing long-term cure.3 The use of liver volumetrics, tridimensional reconstructions with vessel extraction and 3D virtual surgery simulations allows better surgical planning and potentially decrease transfusions, surgery time and complications.4 For major hepatectomies (>4 resected segments), surgical planning with computed angiotomography and liver remnant volume calculation potentially increases the safety of surgery. We report a case in which preoperative 3D surgical simulation was crucial for conducting a safe major hepatectomy in a patient with multiple colorectal liver metastases.

Thoracic aortic size in Brazilian smokers: measures using low-dose chest computed tomography anatomical and epidemiological assessment.

OBJECTIVES: Thoracic aortic aneurysms (TAAs) represent one-third of the hospitalizations for aortic diseases. The prevalence rate depends on the definition of the normal size of the aorta, which is quite variable, depending on the population studied. The aim of this study was to evaluate the characteristics of the thoracic aorta of Brazilian smokers, identifying the normal size of the aorta, presence of anatomical variations, and prevalence of TAA. MATERIALS AND METHODS: A total of 711 patients underwent radiological evaluation with low-dose computed tomography (CT) from January 2013 to July 2014 with the initial objective of lung nodule tracking. Two examiners evaluated these images, and measurements of maximum and serial diameters were performed manually in true orthogonal planes. Serial diameter measurements were taken every 2 cm in the ascending aorta and 5 cm in the descending segment. We searched for anatomical variations, aortic arch type, and correlations between anatomical characteristics, sex, body mass index, and body surface area (BSA). RESULTS: The maximum diameters were 33.61 (standard deviation [SD] 3.88), 28.66 (SD 2.89), and 28.36 mm (SD 3.09) for the ascending segment, aortic arch, and descending segment, respectively. A positive correlation was found between male sex, age, and BSA and aorta diameter. The bovine arch was the most common variation of the aortic arch type, and we found one (0.14%) case of TAA. CONCLUSIONS: This study with low-dose CT allowed the determination of the mean diameters of the ascending aorta, aortic arch, and descending aorta in Brazilian smokers and TAA prevalence.

Signs of impending rupture in abdominal aortic and iliac artery aneurysms by computed tomography: Outcomes in 41 patients.

OBJECTIVES: This study aimed to determine the prevalence of signs of impending rupture (SIR) in asymptomatic patients with abdominal aortic and iliac artery aneurysms, and to evaluate whether these signs were associated with rupture in asymptomatic patients. METHODS: This was a retrospective study of patients with abdominal aortic and iliac artery aneurysms identified on computed tomography (CT) over a 10-year period in a single center. The CT scans were reviewed by two reviewers, and patients with SIR were assigned to one of three groups: (1) early symptomatic (ES), (2) late symptomatic (LS), and (3) always asymptomatic (AA). The four main SIR described in the literature were investigated: 1) crescent sign, 2) focal wall discontinuity of circumferential calcifications, 3) aortic bulges or blebs, and 4) aortic draping. RESULTS: From a total of 759 aortic and iliac aneurysm reports on 2226 CT scans, we identified 41 patients with at least one SIR, and a prevalence of 4.14% in asymptomatic patients. Focal wall discontinuity of circumferential calcifications was the most common sign, and it was present in 46.3% of these patients (19/41); among these, 26 were repaired (ES: 9, LS: 2, AA: 15). Eleven asymptomatic patients underwent follow-up CT. The aneurysm increased in size in 6 of the 11 (54.5%) patients, and three ruptured (all with discontinuity of calcifications), one of which had no increase in diameter. CONCLUSIONS: The presence of focal wall discontinuity of circumferential calcifications was the most common SIR. There was a prevalence of all signs in less than 5% of asymptomatic patients. In unrepaired patients, the signs could be observed on follow-up CT scans with an increase in aneurysm size, indicating that the presence of SIR alone in the absence of other clinical factors or aneurysm characteristics is an insufficient indication for surgery.

Angioplasty and stent placement in symptomatic internal carotid occlusion.

PURPOSE: To report a series of patients with symptomatic internal carotid artery (ICA) occlusion treated with angioplasty and stents. MATERIALS AND METHODS: From a consecutive series of 50 patients experiencing neurologic ischemic symptoms and shown by conventional ultrasonography (US) to have a total ICA occlusion, 16 patients (ages 45-79 years; mean, 63 y; 10 men) were selected between August 2006 to September 2008 to be treated with angioplasty based on discovery of an open ICA distal to the occlusion through contrast-enhanced echo Doppler imaging and/or multislice contrast computed tomography (CT). Angioplasty and stent placement were performed under cerebral protection. Follow-up duplex imaging was performed at 14 days and 3 months and every 6 months thereafter and CT follow-up was performed at 2-9 months; the mean follow-up period was 9.9 months. RESULTS: Lesion crossing and stent placement was successful in 13 of 16 patients. There were no deaths, conversions, cardiac complications, or major strokes. One patient had a transient mild hemiparesis in the upper limb, with total recovery in 3 months. At follow-up, all 13 patients with a good initial result remained with patent arterial lumens and resolution of neurologic ischemic symptoms. After 2-9 months, ICAs with a "string sign" had calibers close or equal to those of normal arteries. CONCLUSIONS: Angioplasty with stent placement is an effective treatment with a low morbidity rate for selected patients who continue to experience neurologic ischemic symptoms despite US findings of total occlusion of the ICA.

Quality and safety innovations in the Radiology Department during the COVID-19 pandemic: a Latin American experience.

Radiology departments were forced to make significant changes in their routine during the coronavirus disease 2019 pandemic, to prevent further transmission of the coronavirus and optimize medical care as well. In this article, we describe our Radiology Department's policies in a private hospital for coronavirus disease 2019 preparedness focusing on quality and safety for the patient submitted to imaging tests, the healthcare team involved in the exams, the requesting physician, and for other patients and hospital environment.

Morphologic criteria of vermiform appendix on computed tomography and a possible risk of developing acute appendicitis.

OBJECTIVE: To evaluate the correlation of morphological criteria of the cecal appendix using computed tomography (CT) and the possible risk of developing acute appendicitis. MATERIALS AND METHODS: Cases were defined as patients with surgically confirmed acute appendicitis who had undergone CT at least twice: at diagnosis and at least one month prior. Controls were defined as emergency patients with abdominal pain who had undergone abdominal CT that excluded acute appendicitis and had also undergone CT at least one month before. RESULTS: 100 cases and 100 controls were selected for inclusion in the final analysis. Comparisons between the cases and controls revealed the following: mean transverse diameter of 0.6 cm (range, 0.4-1.0 cm) versus 0.6 cm (range, 0.6-0.8 cm; p = 0.37); mean length of 6.6 cm (range, 3.5-9.7 cm) versus 6.6 cm (range, 4.5-8.3 cm; p = 0.87); mean angle of 100° (range, 23-178°) versus 86° (range, 43-160°; p = 0.01); vertical descending orientation in 56% versus 45% (p = 0.2); absence of gas in 69% versus 77% (p = 0.34); and presence of an appendicolith in 17% versus 8% (p = 0.08). CONCLUSION: Hypothetical risk factors for obstruction of the vermiform appendix detected on CT were not associated with acute appendicitis. That suggests that factors other than those related to mechanical obstruction are implicated in the pathogenesis of acute appendicitis.

OBJETIVO: Avaliar a correlação de critérios morfológicos do apêndice cecal por tomografia computadorizada (TC) e o risco de apendicite aguda. MATERIAIS E MÉTODOS: Casos foram definidos como apendicite aguda confirmada cirurgicamente que tiveram pelo menos dois exames de TC: um no diagnóstico de apendicite aguda e outro no mínimo um mês antes. O grupo controle foi definido como pacientes emergenciais com dor abdominal com TC de abdome excluindo apendicite aguda e com TC prévia pelo menos um mês antes. RESULTADOS: 100 casos e 100 controles foram selecionados. A comparação das variáveis dos casos e controles revelou: diâmetro transverso médio de 0,6 cm (faixa: 0,4-1,0 cm) versus 0,6 (faixa: 0,6-0,8 cm) (p = 0,37); comprimento médio de 6,6 cm (faixa: 3,5-9,7 cm) versus 6,6 cm (faixa: 4,5-8,3 cm) (p = 0,87); ângulo médio de 100° (faixa: 23-178°) versus 86° (faixa: 43-160°) (p = 0,01); orientação descendente em 56% versus 45% (p = 0,2); ausência de gás em 69% versus 77% (p = 0,34) e presença de apendicólito em 17% versus 8% (p = 0,08). CONCLUSÃO: Fatores obstrutivos hipotéticos do apêndice cecal na TC não foram associados a apendicite aguda. Isso sugere que outros fatores diferentes de obstrução mecânica podem estar implicados na gênese da apendicite aguda.