RESUMO
Idiopathic pulmonary fibrosis (IPF) is a specific form of chronic progressive fibrosing interstitial lung disease with a poor prognosis. High-resolution computed tomography (HRCT) plays an important role in the work-up of patients with suspected IPF. In HRCT IPF is characterized by the pattern of usual interstitial pneumonia (UIP). For a long time only supportive or immunosuppressive treatment was possible. The approval of antifibrotic agents in 2012 marked a turning point and triggered further clinical and scientific interest. Based on the recently gained knowledge the revised version of the international guidelines for the diagnosis of IPF was published in 2018, including instructions for HRCT interpretation. In this continued medical education article the relevant signs in HRCT are presented. The specifications given in the guidelines are elucidated.
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Fibrose Pulmonar Idiopática , Humanos , Fibrose Pulmonar Idiopática/diagnóstico por imagem , Pulmão , Tomografia Computadorizada por Raios XRESUMO
Solitary or multiple pulmonary cysts are a relatively rare finding and should always prompt the search for an underlying cause. High-resolution computed tomography (HRCT) plays a crucial role in the differential diagnosis with morphological findings, such as cyst shape and size, wall consistency, number, distribution and localization of the cysts being the important criteria. The differentiation of diseases with multiple, diffusely distributed cysts from diseases with single or grouped cysts facilitates the definition of the final diagnosis. Associated pulmonary findings, such as nodules, ground-glass opacities and fibrosis or pleural changes also play a role. Possible underlying diseases can have systemic, inhalative, traumatic, genetic or infectious causes.
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Cistos , Pneumopatias , Cistos/diagnóstico por imagem , Diagnóstico Diferencial , Humanos , Pneumopatias/diagnóstico por imagem , Tomografia Computadorizada por Raios XRESUMO
Lung cancer is a histologically, immunologically and therefore morphologically and functionally very heterogeneous group of neoplasms with the highest cancer mortality worldwide. Therefore, the range of diseases mimicking lung cancer is also very broad and includes congenital, infectious and inflammatory changes as well as other benign space-occupying lesions and other primary and secondary pulmonary neoplasms. The difficulty in radiology lies in the ability to diagnose lung cancer with a high degree of certainty. This must take the limits of the specific diagnosis, knowledge of the classical pitfalls and rare entities that can imitate lung cancer into consideration. Narrowing the differential diagnosis requires close interdisciplinary cooperation and consideration of the patient's clinical and medical history. An accurate analysis of the computed tomography (CT) pattern and distribution of the lesions as well as consideration of additional changes and involvement of other organ systems can be the key to the diagnosis. The use of fluorodeoxyglucose positron-emission tomography CT (FDG-PET-CT) is helpful only in a few mimics of lung cancer. The article describes clinical and radiological findings of mimics of lung cancer also pointing out the limitations of CT and PET-CT for the diagnosis.
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Neoplasias Pulmonares , Nódulo Pulmonar Solitário , Fluordesoxiglucose F18 , Humanos , Recém-Nascido , Neoplasias Pulmonares/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Nódulo Pulmonar Solitário/diagnóstico por imagemRESUMO
Radiological evaluation of incidentally detected lung nodules on computed tomography (CT) influences management. We assessed international radiological variation in 1) pulmonary nodule characterisation; 2) hypothetical guideline-derived management; and 3) radiologists' management recommendations.107 radiologists from 25 countries evaluated 69 CT-detected nodules, recording: 1) first-choice composition (solid, part-solid or ground-glass, with percentage confidence); 2) morphological features; 3) dimensions; 4) recommended management; and 5) decision-influencing factors. We modelled hypothetical management decisions on the 2005 and updated 2017 Fleischner Society, and both liberal and parsimonious interpretations of the British Thoracic Society 2015 guidelines.Overall agreement for first-choice nodule composition was good (Fleiss' κ=0.65), but poorest for part-solid nodules (weighted κ 0.62, interquartile range 0.50-0.71). Morphological variables, including spiculation (κ=0.35), showed poor-to-moderate agreement (κ=0.23-0.53). Variation in diameter was greatest at key thresholds (5â mm and 6â mm). Agreement for radiologists' recommendations was poor (κ=0.30); 21% disagreed with the majority. Although agreement within the four guideline-modelled management strategies was good (κ=0.63-0.73), 5-10% of radiologists would disagree with majority decisions if they applied guidelines strictly.Agreement was lowest for part-solid nodules, while significant measurement variation exists at important size thresholds. These variations resulted in generally good agreement for guideline-modelled management, but poor agreement for radiologists' actual recommendations.
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Neoplasias Pulmonares/diagnóstico por imagem , Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Nódulo Pulmonar Solitário/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Guias de Prática Clínica como Assunto , Radiologistas , Reprodutibilidade dos TestesRESUMO
BACKGROUND: Currently 80% of donor lungs are not accepted for transplantation, often due to fluid overload. Our aim was to investigate if forced fluid infusion may be replaced by a new pharmacological therapy to stabilize circulation after brain death in an animal model, and to assess therapy effects on lung function and morphology trough blood gas parameters and state-of-the-art High-resolution CT (HRCT). METHODS: Brain death was caused by surgical decapitation. To maintain mean aortic pressure > 60 mmHg, pigs were treated with forced electrolyte solution infusion (GI; n = 6) or the pharmacological therapy (GII; n = 11). GIII (n = 11) were non-decapitated controls. Lung function was investigated with blood gases and lung morphology with HRCT. RESULTS: GI pigs became circulatory instable 4-6 h after brain death in spite of forced fluid infusion, five pigs showed moderate to severe pulmonary edema on HRCT and median final PaO2 /FiO2 was 29 kPa (Q1; Q3; range 26; 40; 17-76). GII and GIII were circulatory stable (mean aortic pressure > 80 mmHg) and median final PaO2 /FiO2 after 24 h was 72 kPa (Q1; Q3; range 64; 76; 53-91) (GII) and 66 kPa (55; 78; 43-90) (GIII). On HRCT, only two pigs in GII had mild pulmonary edema and none in GIII. More than 50% of HRCT exams revealed unexpected lung disease even in spite of PaO2 /FiO2 > 40 kPa. CONCLUSION: Pharmacological therapy but not forced fluid infusion prevented circulatory collapse and extensive HRCT verified pulmonary edema after acute brain death. HRCT was useful to evaluate lung morphology and revealed substantial occult parenchymal changes justifying efforts toward a more intense use of HRCT in the pre-transplant evaluation.
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Circulação Sanguínea , Morte Encefálica/diagnóstico , Pulmão/diagnóstico por imagem , Animais , Gasometria , Decapitação , Eletrólitos/administração & dosagem , Eletrólitos/uso terapêutico , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Oxigênio/sangue , Respiração com Pressão Positiva , Edema Pulmonar/fisiopatologia , Respiração Artificial , Sus scrofa , Suínos , Tomografia Computadorizada por Raios XRESUMO
Digital chest radiography is still the most common radiological examination. With the upcoming three-dimensional (3D) acquisition techniques the value of radiography seems to diminish. But because radiography is inexpensive, readily available, and requires very little dose, it is still being used for the first-line detection of many cardiothoracic diseases. In the last decades major technical developments of this 2D technique are being achieved. First, hardware developments of digital radiography have improved the contrast to noise, dose efficacy, throughput, and workflow. Dual energy acquisition techniques reduce anatomical noise by splitting a chest radiograph into a soft tissue image and a bone image. Second, advanced processing methods are developed to enable and improve detection of many kinds of disease. Digital bone subtraction by a software algorithm mimics the soft tissue image normally acquired with dedicated hardware. Temporal subtraction aims to rule out anatomical structures clotting the image, by subtracting a current radiograph with a previous radiograph. Finally, computer-aided detection systems help radiologists for the detection of various kinds of disease such as pulmonary nodules or tuberculosis.
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Doenças Cardiovasculares/diagnóstico por imagem , Radiografia Torácica/métodos , Doenças Torácicas/diagnóstico por imagem , Algoritmos , Humanos , Imageamento Tridimensional/métodos , Intensificação de Imagem Radiográfica/instrumentação , Intensificação de Imagem Radiográfica/métodos , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/métodos , Radiografia Torácica/instrumentação , Técnica de SubtraçãoRESUMO
Interstitial lung diseases are a mixed group of diffuse parenchymal lung diseases which can have an acute or chronic course. Idiopathic diseases and diseases with an underlying cause (e.g. collagen vascular diseases) share the same patterns. Thin section computed tomography (CT) plays a central role in the diagnostic work-up. The article describes the most important interstitial lung diseases following a four pattern approach with a predominant nodular or reticular pattern or a pattern with increased or decreased lung density.
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Doenças Pulmonares Intersticiais/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Intensificação de Imagem Radiográfica/métodos , Tomografia Computadorizada por Raios X/métodos , Diagnóstico Diferencial , HumanosRESUMO
The finding of subsolid pulmonary nodules poses a frequent problem in the daily routine of the radiologist. The biological behavior of such subsolid lesions differs significantly from solid nodules. The risk of malignancy is significantly higher in subsolid nodules as compared to solid or purely ground glass opacities or nodules. The recommendations regarding the diagnostic management of subsolid nodules have been adapted according to the tendency of growth and the risk of malignancy. A benign etiology is also seen quite often in subsolid lesions and in this case they will show a reduction of size or disappear completely by the follow-up examination. Therefore, in many cases a short-term follow-up examination is primarily recommended. As the findings will often show no changes for a long period of time, further annual follow-up examinations over a longer, not yet specified period of time are recommended. Subsolid lesions that grow in size and/or show an increase in density or develop a solid part within a ground glass lesion should remain as suspected malignancies until proven otherwise.
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Detecção Precoce de Câncer/métodos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/terapia , Radiografia Torácica/métodos , Nódulo Pulmonar Solitário/diagnóstico por imagem , Nódulo Pulmonar Solitário/terapia , Tomografia Computadorizada por Raios X/métodos , Humanos , Prognóstico , Intensificação de Imagem Radiográfica/métodosRESUMO
CLINICAL/METHODICAL ISSUE: Lung cancer is the most frequent cause of tumor-associated death and only has a good prognosis if detected at a very early tumor stage. METHODICAL INNOVATIONS: For the first time the American National Lung Screening Trial (NLST) could prove that low-dose computed tomography (CT) screening is able to reduce lung cancer mortality by 20 %. PERFORMANCE: To date, however, three much smaller and therefore statistically underpowered European trials could not confirm the positive results of the NLST. The results of the largest European trial NELSON are expected within the next 2 years. In addition, there are a number of open or not yet satisfactorily answered questions, such as the definition of the appropriate screening population, the management of nodules detected by screening, the effects of over-diagnosis and the risk of cumulative radiation exposure. PRACTICAL RECOMMENDATIONS: The success of the NLST prompted several predominantly American professional societies to issue a positive recommendation about the implementation of lung cancer screening in a population at risk. However, potentially conflicting results of European studies and a number of not yet optimized issues justify caution and call for a pooled analysis of European studies in order to provide statistically sound results and to ensure a high efficiency of screening with respect to the radiation applied, mental and physical patient burden and, last but not least, the financial efforts.
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Detecção Precoce de Câncer/estatística & dados numéricos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/prevenção & controle , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Medicina Baseada em Evidências , Humanos , Incidência , Neoplasias Pulmonares/mortalidade , Prognóstico , Doses de Radiação , Reprodutibilidade dos Testes , Fatores de Risco , Sensibilidade e Especificidade , Taxa de SobrevidaRESUMO
BACKGROUND: Chest radiography still represents the most commonly performed X-ray examination because it is readily available, requires low radiation doses and is relatively inexpensive. However, as previously published, many initially undetected lung nodules are retrospectively visible in chest radiographs. STANDARD RADIOLOGICAL METHODS: The great improvements in detector technology with the increasing dose efficiency and improved contrast resolution provide a better image quality and reduced dose needs. METHODICAL INNOVATIONS: The dual energy acquisition technique and advanced image processing methods (e.g. digital bone subtraction and temporal subtraction) reduce the anatomical background noise by reduction of overlapping structures in chest radiography. Computer-aided detection (CAD) schemes increase the awareness of radiologists for suspicious areas. RESULTS: The advanced image processing methods show clear improvements for the detection of pulmonary lung nodules in chest radiography and strengthen the role of this method in comparison to 3D acquisition techniques, such as computed tomography (CT). ASSESSMENT: Many of these methods will probably be integrated into standard clinical treatment in the near future. Digital software solutions offer advantages as they can be easily incorporated into radiology departments and are often more affordable as compared to hardware solutions.
Assuntos
Imageamento Tridimensional/tendências , Neoplasias Pulmonares/diagnóstico por imagem , Intensificação de Imagem Radiográfica/tendências , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/tendências , Radiografia Torácica/tendências , Nódulo Pulmonar Solitário/diagnóstico por imagem , Detecção Precoce de Câncer/tendências , Humanos , Prognóstico , Intensificação de Imagem Radiográfica/métodos , Tomografia Computadorizada por Raios X/tendênciasRESUMO
Since the widespread use of computed tomography (CT), the detection of pulmonary nodules has considerably increased and has become part of the daily clinical routine. In the evaluation of pulmonary nodules, malignant nodules have to be differentiated from benign pulmonary nodules with a high level of confidence. The diagnostic approach for pulmonary nodules depends on the pretest probability for malignancy. For indeterminate pulmonary nodules <8 mm, non-contrast CT observational follow-up is recommended and depending on the size and pretest probability for malignancy, follow-up CT intervals range from 3 to 12 months. For indeterminate pulmonary nodules >8 mm, management is based on patient surgical risk and pretest probability for malignancy. Either CT follow-up alone, 18-fluorodeoxyglucose-positron emission tomography (FDG-PET) or non-surgical biopsy for tissue diagnosis are utilized to evaluate the lesions. For pulmonary nodules with a high pretest probability for malignancy, surgical resection is recommended unless specifically contraindicated.
Assuntos
Fluordesoxiglucose F18 , Radiografia Torácica/métodos , Nódulo Pulmonar Solitário/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Humanos , Achados Incidentais , Compostos RadiofarmacêuticosRESUMO
AIM: To asses the image quality and potential for dose reduction of mobile direct detector (DR) chest radiography as compared with computed radiography (CR) for intensive care unit (ICU) chest radiographs (CXR). METHODS AND MATERIALS: Three groups of age-, weight- and disease-matched ICU patients (n=114 patients; 50 CXR per acquisition technique) underwent clinically indicated bedside CXR obtained with either CR (single read-out powder plates) or mobile DR (GOS-TFT detectors) at identical or 50% reduced dose (DR(50%)). Delineation of anatomic structures and devices used for patient monitoring, overall image quality and disease were scored by four readers. In 12 patients pairs of follow-up CR and DR images were available, and in 15 patients pairs of CR and DR(50%) images were available. In these pairs the overall image quality was also compared side-by-side. RESULTS: Delineation of anatomy in the mediastinum was scored better with DR or DR(50%) than with CR. Devices used for patient monitoring were seen best with DR, with DR(50%) being superior to CR. In the side-by-side comparison, the overall image quality of DR and DR(50%) was rated better than CR in 96% (46/48) and 87% (52/60), respectively. Inter-observer agreement for the assessment of pathology was fair for CR and DR(50%) (κ = 0.33 and κ = 0.39, respectively) and moderate for DR (κ = 0.48). CONCLUSION: Mobile DR units offer better image quality than CR for bedside chest radiography and allow for 50% dose reduction. Inter-observer agreement increases with image quality and is superior with DR, while DR(50%) and CR are comparable.
Assuntos
Unidades Móveis de Saúde/normas , Sistemas Automatizados de Assistência Junto ao Leito , Intensificação de Imagem Radiográfica/métodos , Radiografia Torácica/métodos , Carga Corporal (Radioterapia) , Feminino , Humanos , Unidades de Terapia Intensiva , Masculino , Doses de Radiação , Intensificação de Imagem Radiográfica/instrumentação , Radiografia Torácica/instrumentaçãoRESUMO
AIM: To determine the gender-specific prevalence of pulmonary cysts typical for lymphangioleiomyomatosis (LAM) in adult patients with known tuberous sclerosis complex (TSC). MATERIALS AND METHODS: A retrospective, cross-sectional study in a cohort of 206 adult TSC patients was performed. Institutional review board approval was obtained, and patient informed consent was waived. Patients had routinely undergone abdominal CT scanning between 1996 and 2006. All 186 patients (mean age 38 years; range 19-72 years; 91 (49%) male patients) in whom at least the lung bases were depicted on computed tomography (CT) were included. Images were reviewed for the presence of pulmonary thin-walled cysts. Descriptive statistics, two sample t-test to compare means, and χ(2)-test to compare proportions were applied. RESULTS: CT demonstrated pulmonary thin-walled cysts in the lung bases in 52 (28%) of 186 patients. Size varied from 2mm in diameter to more than 2 cm. Pulmonary cysts were detected in 40 (42%) of 95 female patients and in 12 (13%) of 91 male patients (p<0.001). In general, cysts were larger and more numerous in women than in men. Only minimal cystic changes were found in four women and two men, moderate cystic changes were seen in three women and seven men, but considerable cystic changes were seen almost exclusively in women (33 women versus three men). CONCLUSION: CT demonstrated thin-walled pulmonary cysts in the lung bases in 28% of 186 included patients with tuberous sclerosis complex. Female patients were more affected than male patients.
Assuntos
Neoplasias Pulmonares/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Linfangioleiomiomatose/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Esclerose Tuberosa/diagnóstico por imagem , Adulto , Idoso , Estudos Transversais , Feminino , Humanos , Pulmão/fisiopatologia , Pneumopatias/diagnóstico por imagem , Pneumopatias/epidemiologia , Neoplasias Pulmonares/epidemiologia , Linfangioleiomiomatose/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Distribuição por Sexo , Esclerose Tuberosa/epidemiologia , Adulto JovemRESUMO
A number of important technical advances made in recent years in the area of both digital radiography as well as multidetector computed tomography (MDCT) have improved detection and staging of bronchial carcinoma. The aim of elaborate processing such as temporal subtraction, rib suppression, dual energy subtraction or CAD is to aid the radiologist in detecting lung tumors at the earliest stage possible. For both CT and radiography techniques the differentiation between true and false positive lesions seems to be the biggest challenge. MDCT with multiplanar projections is the imaging method of choice for staging of the extent of local tumor spread (T staging), while N staging and M staging are the domain of positron emission tomography (PET) or even better of integrated PET/CT. Management rules for follow-up of solid and semi-solid lesions seen in CT consider the risks of the patient and are summarized in international guidelines. In 2009 a new 7th edition of the TNM classification was published, which, among other aspects, sub-classifies tumor size more specifically and the presence of a satellite nodule in the tumor lobe is down-staged to T3 and no longer determines tumor resectability. The N staging was not modified. One of the most important new features is the fact that the new classification no longer applies only to non-small cell lung cancer (NSCLC) but also to SCLC and carcinoid tumors.
Assuntos
Carcinoma Broncogênico/diagnóstico por imagem , Processamento de Imagem Assistida por Computador , Neoplasias Pulmonares/diagnóstico por imagem , Intensificação de Imagem Radiográfica , Tomografia Computadorizada por Raios X , Carcinoma Broncogênico/patologia , Humanos , Neoplasias Pulmonares/patologia , Metástase Linfática/patologia , Estadiamento de Neoplasias , Tomografia por Emissão de Pósitrons , Prognóstico , Sensibilidade e Especificidade , Técnica de Subtração , Tomografia Computadorizada EspiralRESUMO
Osteochondromas are a very common and usually asymptomatic entity which may originate anywhere in the appendicular and axial skeleton. However, the ribs are a rare site of origin and here they may prove symptomatic for mechanical reasons. In this case report, we describe an unusual case of a symptomatic osteochondroma of the rib secondary to its location and unique shape, ultimately requiring surgical intervention.
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BACKGROUND AND PURPOSE: To investigate the prevalence of subependymal giant cell ependymomas (SEGA) in patients with tuberous sclerosis complex (TSC). METHODS: We performed a retrospective cross-sectional study in a cohort of 285 patients with known TSC. Institutional review board approval was obtained. We included all 214 TSC-patients who had received a contrast-enhanced computed tomography (CT) scan of the brain. The most recent scan was evaluated for SEGA and presence of hydrocephalus. Additionally, a literature search was performed, and pooled estimates of SEGA prevalence in TSC were calculated. We used descriptive statistics, two sample t-test, chi-squared-test, and meta-analysis as appropriate. RESULTS: Computed tomography showed radiological evidence of SEGA in 43 of the 214 TSC-patients (20%); 23 of 105 men (22%) and 20 of 109 women (18%; P = .52). Average maximum tumor size was 11.4 mm (range, 4-29 mm). Patients with SEGA (mean, 31 years; range, 16-58 years) were on average younger than patients without SEGA (mean, 37 years; range, 10-72 years; P = 0.007). No association between tumor size and patient age was detected. Nine patients had bilateral SEGA. Hydrocephalus was present in six of the 43 patients (14%). Meta-analysis of reported prevalence and our current study showed that studies using radiological evidence to diagnose SEGA gave a higher pooled estimate of the prevalence of SEGA in TSC (0.16; 95% CI: 0.12, 0.21) than studies using mainly histopathological evidence of SEGA (0.09; 95% CI: 0.07, 0.12). CONCLUSIONS: In our cohort, CT demonstrated evidence of SEGA in 20% of TSC-patients. Prevalence of SEGA in TSC is higher in studies using radiological evidence to diagnose SEGA than in studies using histopathological evidence.
Assuntos
Astrocitoma/epidemiologia , Neoplasias Encefálicas/epidemiologia , Esclerose Tuberosa/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Astrocitoma/diagnóstico por imagem , Astrocitoma/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Encéfalo/fisiopatologia , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Aqueduto do Mesencéfalo/diagnóstico por imagem , Aqueduto do Mesencéfalo/patologia , Aqueduto do Mesencéfalo/fisiopatologia , Criança , Estudos de Coortes , Comorbidade , Estudos Transversais , Feminino , Humanos , Hidrocefalia/epidemiologia , Masculino , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Valor Preditivo dos Testes , Prevalência , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Esclerose Tuberosa/diagnóstico por imagem , Esclerose Tuberosa/patologia , Adulto JovemAssuntos
Detecção Precoce de Câncer/métodos , Neoplasias Pulmonares/diagnóstico por imagem , Proteção Radiológica/métodos , Nódulo Pulmonar Solitário/diagnóstico por imagem , Humanos , Doses de Radiação , Intensificação de Imagem Radiográfica/métodos , Radiografia Torácica/métodos , Tomografia Computadorizada por Raios X/métodosRESUMO
This corrects the article DOI: 10.1038/srep46479.
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PURPOSE: Compare the right ventricle to left ventricle (RV/LV) diameter ratio obtained from axial pulmonary CT angiograms (CTPA) with those derived from automatically generated 4-chamber (4-CH) reformats in patients with suspected pulmonary embolism (PE). METHODS: In this institutional review board-approved study we included 120 consecutive non ECG-gated CTPA from 3 institutions (mean age 60 ± 16 years; 71 women). Twenty 64-slice CTPA with PE and 20 without PE were selected per institution. For each patient the RV/LV diameter ratio was obtained from both axial CTPA images and automatically generated 4-CH reformats. Measurements were performed twice in two separated sessions by 2 experienced radiologists and 2 residents. The differences between the measurements on both views were evaluated. RESULTS: The 4-CH view was successfully obtained in 113 patients. The mean axial and 4-CH diameter ratios were comparable for three of the four readers (p = 0.56, p = 0.13, p = 0.08). Although the mean diameters (1.0 and 1.03 respectively) for one resident were significantly different (p = 0.013), the difference of 0.03 seems negligible in clinical routine. Three readers achieved equally high intra-reader agreements with both measurements (ICCs of 0.94, 0.95 and 0.96), while one reader showed a different variability with ICCs of 0.96 for the axial view and 0.91 for the 4-CH view. The inter-reader agreement was equally high for both measurement types with ICCs of 0.95 and 0.94, respectively. CONCLUSION: In patients with suspected PE, RV/LV diameters ratio can be measured with the same reproducibility and accuracy using an automatically generated 4-CH view compared to the axial view.
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Algoritmos , Angiografia Coronária/métodos , Ventrículos do Coração/diagnóstico por imagem , Hipertrofia Ventricular Direita/diagnóstico por imagem , Reconhecimento Automatizado de Padrão/métodos , Embolia Pulmonar/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Feminino , Humanos , Hipertrofia Ventricular Direita/etiologia , Imageamento Tridimensional/métodos , Masculino , Pessoa de Meia-Idade , Embolia Pulmonar/complicações , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
OBJECTIVE: To assess whether the performance of a computer-assisted detection (CAD) algorithm for acute pulmonary embolism (PE) differs in pulmonary CT angiographies acquired at various institutions. METHODS: In this retrospective study, we included 40 consecutive scans with and 40 without PE from 3 institutions (n = 240) using 64-slice scanners made by different manufacturers (General Electric; Philips; Siemens). CAD markers were classified as true or false positive (FP) using independent evaluation by two readers and consultation of a third chest radiologist in discordant cases. Image quality parameters were subjectively scored using 4/5-point scales. Image noise and vascular enhancement were measured. Statistical analysis was done to correlate image quality of the three institutions with CAD stand-alone performance. RESULTS: Patient groups were comparable with respect to age (p = 0.22), accompanying lung disease (p = 0.12) and inpatient/outpatient ratio (p = 0.67). The sensitivity was 100% (34/34), 97% (37/38) and 92% (33/36), and the specificity was 18% (8/44), 15% (6/41) and 13% (5/39). Neither significantly differed between the institutions (p = 0.21 and p = 0.820, respectively). The mean number of FP findings (4.5, 6.2 and 3.7) significantly varied (p = 0.02 and p = 0.03), but median numbers (2, 3 and 3) were comparable. Image quality parameters were significantly associated with the number of FP findings (p<0.05) but not with sensitivity. After correcting for noise and vascular enhancement, the number of FPs did not significantly differ between the three institutions (p = 0.43). CONCLUSIONS: CAD stand-alone performance is independent of scanner type but strongly related to image quality and thus scanning protocols.