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BACKGROUND: Surveillance of sporadic renal angiomyolipomas is a growing issue for physicians and radiologists. Current treatment recommendations favor active surveillance. However, the evidence underlying these is based on small case series, which also typically include angiomyolipomas associated with tuberous sclerosis. PURPOSE: To evaluate the natural growth pattern of sporadic renal angiomyolipomas in patients without tuberous sclerosis. MATERIAL AND METHODS: A retrospective review was performed in three separate tertiary referral centers. A keyword search of each institutions PACS history was performed. Inclusion criteria were angiomyolipomas > 1 cm in size, three years of follow-up, and lesions requiring treatment before reaching three years of follow-up. Exclusion criteria included a diagnosis of tuberous sclerosis, pregnancy, prior treatment with embolization without any prior imaging, and lesions which were treated on presentation. Growth of the angiomyolipomas was evaluated on the basis of maximum dimension on initial and follow-up images. RESULTS: Sixty-three patients were identified in total, with 64 lesions eligible for inclusion. The majority of patients were women (55/63). The mean age at which the angiomyolipomas discovered was 56.4 years. Mean total growth was 0.085 mm and mean follow-up was 65.5 months. At initial measurement, the mean maximum dimension of the lesions in our cohort was 2.08 cm. After follow-up, this was 2.16 cm. The average rate of growth was 0.015 cm per year. CONCLUSION: Sporadic angiomyolipomas exhibit minimal, if any, natural growth. Current surveillance strategies could be relaxed.
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Angiomiolipoma/diagnóstico por imagem , Angiomiolipoma/patologia , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/patologia , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia/métodos , Adulto , Idoso , Progressão da Doença , Feminino , Seguimentos , Humanos , Rim/diagnóstico por imagem , Rim/patologia , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
Traumatic lower urinary tract injuries are uncommon and mainly occur in patients with severe trauma and multiple abdominopelvic injuries. In the presence of other substantial injuries, bladder and urethral injuries may be overlooked and cause significant morbidity and mortality. Therefore, it is important that radiologists are familiar with mechanisms and injuries that are high risk for bladder and urethral trauma. We review the imaging findings associated with these injuries and the appropriate modalities and techniques to further evaluate the patient and accurately diagnose these injuries. Computed tomography cystography and conventional retrograde urethrography are effective tools in identifying injuries to the lower urinary tract and play a crucial role in patient care and prognosis.
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Uretra/lesões , Bexiga Urinária/lesões , Ferimentos e Lesões/diagnóstico por imagem , Cistografia , Humanos , Tomografia Computadorizada por Raios X , Uretra/diagnóstico por imagem , Bexiga Urinária/diagnóstico por imagem , Ferimentos e Lesões/etiologia , Ferimentos e Lesões/terapiaRESUMO
Modern advances in the medical imaging layered onto sophisticated trauma resuscitation strategies in highly organized regionalized trauma systems have created a paradigm shift in the management of severely injured patients. Although immediate exploratory surgery to identify and control life-threatening injuries still has its place, accelerated image acquisition and interpretation procedures now make it rare for trauma surgeons in major centers to venture into damage control surgery unaided by computed tomography (CT) or other imaging, particularly in cases of blunt trauma. Indeed, because of the high incidence of clinically occult injuries associated with major mechanism trauma, and even lower energy trauma in frail or elderly patients, CT imaging has become as invaluable as physical examination, if not more so, in critical decision-making in support of optimal outcomes. In particular, whole-body computed tomography (WBCT) completed promptly after initial assessment of a major trauma provides a quick, comprehensive survey of injuries that enables better surgical planning, obviates the need for multiple subsequent studies, and permits specialized reconstructions when needed. For those at risk for problematic occult injury after modest trauma, WBCT facilitates safer discharge planning and simplified follow-up. Through standardized guidelines, streamlined protocols, synoptic reporting, accessible web-based platforms, and active collaboration with clinicians, radiologists dedicated to trauma and emergency imaging enable clearer understanding of complex injuries in high-risk patients which leads to superior clinical decision-making. Whereas dated dogma has long warned that the CT scanner is the last place to take a challenging trauma patient, modern practice suggests that, more often than not, early comprehensive imaging can be done safely and efficiently and is in the patient's best interest. This article outlines how the role of diagnostic imaging for major trauma has evolved considerably in recent years.
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Tomada de Decisão Clínica/métodos , Traumatismo Múltiplo/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Imagem Corporal Total/métodos , Ferimentos não Penetrantes/diagnóstico por imagem , Humanos , Escala de Gravidade do FerimentoRESUMO
Dual-energy computed tomography (CT) is a promising tool with increasing availability and multiple emerging and established clinical applications in neuroradiology. With its ability to allow characterization of materials based on their differential attenuation when imaged at two different energy levels, dual-energy CT can help identify the composition of brain, neck, and spinal components. Virtual monoenergetic imaging allows a range of simulated single energy-level reconstructions to be created with postprocessing. Low-energy reconstructions can aid identification of edema, ischemia, and subtle lesions due to increased soft tissue contrast as well as increasing contrast-to-noise ratios on angiographic imaging. Higher energy reconstructions can reduce image artifact from dental amalgam, aneurysm clips and coils, spinal hardware, dense contrast, and dense bones. Differentiating iodine from hemorrhage may help guide management of patients after thrombectomy and aid diagnosis of enhancing tumors within parenchymal hemorrhages. Iodine quantification may predict hematoma expansion in aneurysmal bleeds and outcomes in traumatic brain injury. Calcium and bone subtraction can be used to distinguish hemorrhage from brain parenchymal mineralization as well as improving visualization of extra-axial lesions and vessels adjacent to dense plaque or skull. This article reviews the basics of dual-energy CT and highlights many of its clinical applications in the evaluation of acute neurological presentations.
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Neuroimagem/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/métodos , Tomografia Computadorizada por Raios X/métodos , Meios de Contraste , HumanosRESUMO
Coronavirus Disease 2019 (COVID-19) is the disease caused by the novel coronavirus officially named the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), declared as a pandemic by the World Health Organization on March 11, 2020. The COVID-19 pandemic presents an unprecedented challenge to emergency radiology practice. The continuity of an effective emergency imaging service for both COVID-19 and non-COVID-19 patients is essential, while adhering to best infection control practices. Under the direction of the Board of the Canadian Association of Radiologists, this general guidance document has been synthesized by collaborative consensus of a group of emergency radiologists. These recommendations aim to assist radiologists involved in emergency diagnostic imaging to help mitigate the spread of COVID-19 and continue to add value to patient care in the emergency setting.
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Betacoronavirus , Infecções por Coronavirus/prevenção & controle , Serviço Hospitalar de Emergência/organização & administração , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Serviço Hospitalar de Radiologia/organização & administração , COVID-19 , Canadá , Humanos , Radiologistas , SARS-CoV-2RESUMO
BACKGROUND & AIMS: Administration of infliximab to patients with acute severe ulcerative colitis (ASUC) (rescue therapy) can reduce the rate of early colectomy (within 12 months), but long-term rates of colectomy are the same as those of the pre-biologic era for these patients. The half-life of infliximab is shorter in patients with ASUC than in patients with non-severe UC, so more frequent dosing might be required to produce a therapeutic effect. METHODS: We performed a retrospective analysis of 50 hospitalized patients who received infliximab for steroid-refractory ASUC at a single academic center from September 2005 through 2013. In 2011 an accelerated dosing strategy for infliximab was introduced; we compared outcomes of standard and accelerated dosing regimens. One group of patients (n = 35) were placed on a standard dosing regimen for infliximab and then given the drug at 0, 2, and 6 weeks and then every 8 weeks thereafter. A second group (n = 15) were placed on an accelerated regimen and received 3 induction doses of infliximab within a median period of 24 days. Rates of colectomy were compared between the groups during induction and follow-up periods. RESULTS: There were no differences between groups in median baseline levels of C-reactive protein, albumin, or hemoglobin. The rate of colectomy during induction therapy was significantly lower with the accelerated regimen (6.7%, 1 of 15) than with the standard regimen (40%, 14 of 35) (Fisher exact test, P = .039). The standard regimen was associated with shorter time to colectomy (log-rank test, P = .042). Among patients who completed induction therapy, subsequent need for colectomy was similar between the groups during the follow-up period. Multivariate analysis showed that factors independently associated with successful induction therapy were level of albumin (g/L) when the treatment began (P = .003) and the accelerated dosing regimen (P = .03). CONCLUSIONS: In patients with ASUC, an accelerated infliximab induction strategy reduces the need for early colectomy. An intensified infliximab dosing strategy in response to clinical or laboratory signs of breakthrough inflammation merits consideration in prospective studies.
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Colectomia , Colite Ulcerativa/tratamento farmacológico , Fatores Imunológicos/administração & dosagem , Quimioterapia de Indução/métodos , Infliximab/administração & dosagem , Adulto , Animais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do TratamentoAssuntos
Apendicite , Doença Aguda , Humanos , Radiologistas , Tomografia Computadorizada por Raios XRESUMO
OBJECTIVE: A radiology sign that references a resemblance to something which is not actually present within an image has been termed a 'metaphoric' sign. Metaphoric signs are widely described in the literature and commonly used in teaching as a form of pattern recognition, or 'pareidolia'. However, the educational benefit of metaphoric signs has not been previously assessed. We aimed to assess the utility of metaphoric signs in medical student teaching. MATERIALS AND METHODS: Fifteen radiology cases were prepared into two lecture formats for medical student education. A 'test' lecture utilizing metaphoric radiology signs to describe the appearance of the cases and a 'control' lecture where pathology was compared to normal anatomical appearances without reference to metaphoric signs. Forty-nine volunteer medical students were randomized with cluster sampling to receive either the test or control lecture. Four days later, students were quizzed to determine retention of knowledge and to assess interest in the lecture on a visual analogue scale from 0 to 100. RESULTS: The median interest level of the test group (69.5) was higher than the control group (50) (pâ¯=â¯0.001). The mean quiz score was higher in the test group (34.5) than in the control group (29) (Difference 5.5, 95% confidence interval 0.08-10.92, pâ¯=â¯0.047). CONCLUSION: The use of metaphoric signs in radiology education of medical students increased interest, descriptive ability and short-term knowledge retention, compared to the same material taught with normal anatomy correlation. Metaphoric signs should be considered as a useful radiology teaching tool.
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Educação Médica , Radiologia , Estudantes de Medicina , Capacitação de Professores , HumanosRESUMO
PURPOSE: In recent years, there has been increased recognition of the benefits of teaching by active learning. However, there is a paucity of experimental studies utilizing active learning in undergraduate radiology rotations, which is traditionally a passive learning experience. We designed a new radiology rotation that integrated teaching by active learning. We prospectively examined the efficacy of this new rotation compared to our standard rotation in terms of students' radiological competency and attitudes toward radiology, as well as impact on departmental efficiency. METHODS: This was a prospective cohort study involving fourth year medical students completing a 1-week radiology rotation at our department between January and April 2018. One cohort completed a rotational model which incorporated active learning sessions (integrated cohort) while the remainder were taught using traditional passive learning methods (standard cohort). All participants completed a radiology examination before and after the rotation and were surveyed on their attitudes toward radiology. RESULTS: A total of 105 students enrolled in the study. The mean postrotation competency score obtained by the integrated cohort was significantly higher than that obtained by the standard cohort (82% vs 62%; P < 0.001). The integrated rotation freed up 7 hours of radiologists' time per week. While the students completing the integrated rotation had a more positive perception of radiology, they were no more likely to express a desire to pursue a career in radiology. CONCLUSIONS: The integration of active learning sessions into an undergraduate radiology rotation results in an improvement in students' postrotation radiological competency and attitudes toward radiology.
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Atitude do Pessoal de Saúde , Competência Clínica , Educação de Graduação em Medicina , Aprendizagem Baseada em Problemas/métodos , Radiologia/educação , Avaliação Educacional , Eficiência Organizacional , Feminino , Humanos , Masculino , Estudos Prospectivos , Adulto JovemRESUMO
PURPOSE: Prospective radiology fellows often rely on the internet to obtain information with regard to the application process for and the unique qualities of different fellowship programs. The aim of this study was to analyze the content of websites of the United States' and Canadian cardiothoracic radiology fellowships. METHODS: All active Cardiothoracic Radiology fellowship websites as of July 2019 were evaluated and compared using 25 criteria in the following domains: Application, Recruitment, Clinical Training, Education/Research, and Incentives. Program website information availability was compared by geographic region. RESULTS: There were 60 active cardiothoracic radiology fellowships, and 59 of these fellowships had a dedicated fellowship website. Websites, on average, had 9.3 of the 25 criteria (37.2%). The mean number of schools that satisfied the criterion in the "Incentives" domain ([7.75/59] 10.5%±2.8%) was significantly lower than that for the "Application Process" domain ([40.50/59]; 68.7%±40.6%) (P=0.01). There was no significant difference in the information content of programs in different geographic regions (P=0.246). CONCLUSION: Most cardiothoracic radiology fellowship websites were lacking content relevant to prospective fellows. Provision of more relevant and easily accessible online content may support programs to better inform and recruit residents and to promote the specialty of cardiothoracic radiology.
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Bolsas de Estudo/métodos , Internet , Internato e Residência/métodos , Seleção de Pessoal/métodos , Radiologia/educação , Canadá , Humanos , Estados UnidosRESUMO
OBJECTIVE: To examine the effect of metabolic syndrome and psoriatic disease-related variables on coronary plaque burden in psoriatic arthritis (PsA) patients. METHODS: Fifty PsA patients without symptoms of coronary artery disease (CAD) (25 with metabolic syndrome and 25 without metabolic syndrome) and 50 age- and sex-matched controls underwent 64-slice coronary computed tomography angiography. Plaque localization, segment involvement score (SIS), segment stenosis score (SSS), and total plaque volume (TPV) were calculated. Plaques were classified as calcified, mixed, or noncalcified. Kruskal-Wallis test, rank correlations, and linear regression analyses were used to study the relationship between PsA, metabolic syndrome, and plaque burden. RESULTS: Plaques were found in 76% of PsA patients versus 44% of controls (P = 0.001), and a higher proportion of patients with PsA had affected coronary vessels (P = 0.007). SIS, SSS, and TPV were greater in PsA patients than controls (P = 0.003, P = 0.001, and P ≤ 0.001, respectively). More PsA patients had mixed plaques, and mixed plaque volume was higher than in controls (P < 0.001). PsA patients with metabolic syndrome and those without metabolic syndrome had similar plaque burdens and types. SIS, SSS, and TPV did not show significant relationships with features of metabolic syndrome, but did significantly correlate with disease activity measures. TPV was associated with a diagnosis of PsA (B = 0.865, P = 0.008), but not with metabolic syndrome. Age, highest C-reactive protein level, highest swollen joint count, disease duration, and plasma glucose level were independent predictors of higher plaque burden in PsA. CONCLUSION: PsA is associated with accelerated coronary plaque formation, particularly mixed plaques, independent of metabolic disease. Psoriatic disease activity and severity may predict coronary plaque burden better than traditional risk factors.
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Artrite Psoriásica/complicações , Doença da Artéria Coronariana/patologia , Síndrome Metabólica/complicações , Placa Aterosclerótica/patologia , Adulto , Idoso , Angiografia por Tomografia Computadorizada/métodos , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/patologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Placa Aterosclerótica/complicações , Placa Aterosclerótica/diagnóstico por imagem , Fatores de Risco , Índice de Gravidade de DoençaRESUMO
INTRODUCTION: Breast Arterial Calcification (BAC) on digital mammography has been associated with an increased risk of Coronary Artery Disease (CAD). We aimed to investigate the association of BAC with findings on Coronary Computed Tomography Angiography (CCTA) within a cohort of women from the national breast screening program. METHODS: Symptomatic women (chest pain) aged between 50 and 65 who underwent a CCTA and who also had a screening mammography between 2014 and 2015 were recorded. BAC and CAD-RADS™: Coronary Artery Disease-Reporting and Data System were scored by separate blinded specialist radiologists. Cardiac risk factors were recorded. Patients' cardiac follow up (with Exercise Stress Test, Percutaneous Coronary Intervention or echocardiography) and cardio-protective medications were also documented. RESULTS: 219 eligible women underwent a CCTA. Of these, 104 patients also underwent digital mammography. Using standard linear regression BAC was identified as a significant predictor of CAD-RADs ≥3 disease. Using binomial logistic regression, BAC remained associated with CAD-RADs ≥3 (p=0.023). A significantly higher proportion of patients with BAC >1 were on cardio-protective medications (p=0.041) and had medications initiated or changed, or had further cardiac investigation (p=0.037 and p=0.019, respectively) than those with no BAC, after a mean follow-up of 20.6 (range 15-27) months. CONCLUSION: BAC diagnosed on 2 yearly screening mammography predicts CAD-RADs ≥3 disease in symptomatic patients.
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Artérias/patologia , Doenças Mamárias/diagnóstico , Mama/patologia , Calcinose/diagnóstico , Doença da Artéria Coronariana/diagnóstico , Mamografia , Idoso , Artérias/diagnóstico por imagem , Mama/diagnóstico por imagem , Doenças Mamárias/diagnóstico por imagem , Doenças Mamárias/patologia , Calcinose/diagnóstico por imagem , Dor no Peito/diagnóstico , Dor no Peito/etiologia , Angiografia Coronária/métodos , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/diagnóstico por imagem , Feminino , Humanos , Modelos Logísticos , Mamografia/métodos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Fatores de RiscoRESUMO
PURPOSE: To assess rates of complications, secondary interventions, survival, and cause of death following endovascular abdominal aortic aneurysm (AAA) repair over a 10-year period. MATERIALS AND METHODS: Single-institution retrospective cohort study of all patients undergoing primary endovascular aortic aneurysm repair (EVAR) between July 2006 and June 2015. The population constituted 175 patients with 163 fusiform and 12 saccular AAAs. Of these, 149 (85%) were male, with mean age 75.4 (±7.1) years. Patients were followed up until June 30, 2016. Cause of death was determined from the national death register. RESULTS: Mean follow-up was 34.4 (±24.4) months. The secondary intervention rate was 9.7%, and there were 4 aneurysm ruptures (0.8% annual incidence). Thirty-day mortality was 0.6%. Survival at 1, 3, and 5 years was 93.1%, 84%, and 64.9%, respectively. Forty-eight patients died during follow-up, 3 secondary to rupture, leading to overall and aneurysm-related death rates of 9.7 and 0.6 per 100 person-years. All other deaths were due to nonaneurysm causes, most commonly cardiovascular (n = 15), pulmonary (n = 13), and malignancy (n = 9). Baseline renal impairment ( P < .001), ischemic heart disease ( P < .05), age greater than 75 years ( P < .05), and urgent/emergency EVAR were associated with inferior long-term survival. Type II endoleak negatively influenced fusiform aneurysm sac regression ( P = .02), but there was no association between survival and occurrence of any complication or secondary intervention. CONCLUSION: The majority of deaths during medium-term follow-up post-EVAR are due to nonaneurysm-related causes. Survival is determined by the following baseline factors: renal impairment, ischemic heart disease, advanced age, and the presence of a symptomatic/ruptured aneurysm.
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Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular , Procedimentos Endovasculares , Idoso , Idoso de 80 Anos ou mais , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/mortalidade , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/mortalidade , Causas de Morte , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/mortalidade , Feminino , Humanos , Irlanda , Estimativa de Kaplan-Meier , Masculino , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do TratamentoRESUMO
AIM: To assess the diagnostic accuracy of common carotid artery intima media thickness (CIMT) for coronary artery disease (CAD) detection in patients with obstructive sleep apnoea (OSA). MATERIALS & METHODS: Patients with clinically suspected OSA prospectively underwent polysomnography (PSG), ultrasound CIMT measurement and coronary computed tomography angiography (CTA). An average CIMT of ≥0.9 mm in either common carotid artery designated as a positive test. Coronary CTA was the reference standard for the presence of CAD. Coronary plaque presence, volume, density and type were correlated with CIMT findings. RESULTS: 35 consecutive male patients were enrolled from sleep clinic. Two patients had no evidence of OSA on PSG (apnoea-hypopnea index [AHI]<5/hr), and were excluded. Of the remaining 33, 18 (54%) had mild-moderate OSA (AHI 5-30/hr) and 15 (46%) had severe OSA (AHI >30/hr). Eight (24%) patients had CAD on coronary CTA. Coronary plaques were predominantly non- or partly calcified, and located in proximal coronary artery segments. Sensitivity, specificity, positive and negative predictive and likelihood ratios for a positive CIMT (≥0.9 mm) in diagnosing CAD were 0.5 (95% confidence interval: 0.76-0.12), 0.96 (1-0.89), 80, 85.7, 12.5 and 0.52 respectively. The adjusted odds ratio was 40.8. CONCLUSION: In patients with OSA, CIMT is a highly specific but poorly sensitive test for detecting CAD.
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Doenças das Artérias Carótidas/diagnóstico por imagem , Espessura Intima-Media Carotídea , Angiografia por Tomografia Computadorizada , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Tomografia Computadorizada Multidetectores , Placa Aterosclerótica , Apneia Obstrutiva do Sono/complicações , Adulto , Idoso , Doenças das Artérias Carótidas/complicações , Doença da Artéria Coronariana/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Polissonografia , Valor Preditivo dos Testes , Estudos Prospectivos , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Apneia Obstrutiva do Sono/diagnósticoRESUMO
PURPOSE: Medical journals use social media as a means to disseminate new research and interact with readers. The microblogging site Twitter is one such platform. The aim of this study was to analyze the recent use of Twitter by the leading radiology journals. METHODS: The top 50 journals by Impact Factor were included. Twitter profiles associated with these journals, or their corresponding societies, were identified. Whether each journal used other social media platforms was also recorded. Each Twitter profile was analyzed over a one-year period, with data collected via Twitonomy software. Klout scores of social media influence were calculated. Results were analyzed in SPSS using Student's t test, Fisher contingency tables, and Pearson correlations to identify any association between social media interaction and Impact Factors of journals. RESULTS: Fourteen journals (28%) had dedicated Twitter profiles. Of the 36 journals without dedicated Twitter profiles, 25 (50%) were associated with societies that had profiles, leaving 11 (22%) journals without a presence on Twitter. The mean Impact Factor of all journals was 3.1 ± 1.41 (range, 1.7-6.9). Journals with Twitter profiles had higher Impact Factors than those without (mean, 3.37 vs 2.14; P < .001). There was no statistically significant difference between the Impact Factors of the journals with dedicated Twitter profiles and those associated with affiliated societies (P = .47). Since joining Twitter, 7 of the 11 journals (64%) experienced increases in Impact Factor. A greater number of Twitter followers was correlated with higher journal Impact Factor (R2 = 0.581, P = .029). CONCLUSIONS: The investigators assessed the prevalence and activity of the leading radiology journals on Twitter. Radiology journals with Twitter profiles have higher Impact Factors than those without profiles, and the number of followers of a journal's Twitter profile is positively associated with Impact Factor.