RESUMO
OBJECTIVE. The aim of this study was to develop a low-dose radiography protocol for the neonatal ICU (NICU) using a new mobile digital radiography system with advanced denoising image processing and to evaluate the noninferiority of that protocol. SUBJECTS AND METHODS. In this prospective randomized study, 40 neonates in the NICU underwent radiography of the thorax and abdomen with two different mobile radiography units: conventional technique on one unit (50 kV, 1.6 mAs, and no additional filtration) and a new technique on another unit (54 kV, 0.1-mm Cu filtration). Three low-dose protocols for the second unit were developed in a phantom study: protocol A (100% equivalent dose with conventional protocol), protocol B (80% equivalent dose), and protocol C (64% equivalent dose). The noninferiority of each low-dose protocol was assessed by three independent readers using image quality criteria. RESULTS. Forty patients each underwent three pairs of radiography examinations (protocol A and the conventional protocol, protocol B and the conventional protocol, and protocol C and the conventional protocol), except one pair that did not include one image of the conventional protocol. The interrater reliability among the three readers was 0.91 (p < 0.001). Both of the low-dose protocols (B and C) were statistically noninferior to the conventional protocol with respect to overall image quality. Protocol B better depicted almost all anatomic landmarks and had better overall image quality than the conventional protocol. CONCLUSION. Using appropriate technique and acquisition factors, radiation dose can be lowered on a digital radiography system without significant effect on the image quality by adding filtrations and a new denoising technique.
Assuntos
Intensificação de Imagem Radiográfica/métodos , Intensificação de Imagem Radiográfica/normas , Protocolos Clínicos , Feminino , Humanos , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Masculino , Imagens de Fantasmas , Estudos Prospectivos , Doses de Radiação , Método Simples-CegoRESUMO
PURPOSE: This technical note presents an inexpensive tool and method for determining lead equivalency using digital radiography x-ray equipment. METHODS: A test tool was developed using commercially available lead tape (3M™ Lead Foil Tape 421). The test tool consisted of nine varying lead thick squares arranged in a larger square (0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, and 1.0 mm). It was imaged on a DR plate with a digital portable x-ray unit across a range of energies (60-120 kVp) and two beam filtrations. Lead equivalency was determined by using the linear relationship between dose to the detector and pixel values in the raw images. The lead equivalency of the tape was validated using known lead thicknesses (physically measured with caliper). Additional lead equivalency measurements were made for protective eyewear, a thyroid shield, and a lead apron. RESULTS: The test tool and method measured the two known lead thicknesses to be -9.7% to 7.1% different from the actual values across the range of energies under normal x-ray beam conditions and under a 1-mm copper filtered x-ray beam. The additional lead equivalency measurements of radiation protection apparel across energies ranged from -6% to 20% for both beam conditions when compared with the values provided by the manufacturer. CONCLUSION: This work validates the test tool and methodology as an inexpensive alternative to checking the lead equivalency of radiation protection apparel in a clinical setting. The methodology is equipment independent with a few prerequisites.
Assuntos
Processamento de Imagem Assistida por Computador/normas , Chumbo , Roupa de Proteção , Proteção Radiológica/normas , Intensificação de Imagem Radiográfica/normas , Radiografia/normas , Desenho de Equipamento , Filtração/instrumentação , Humanos , Processamento de Imagem Assistida por Computador/métodos , Doses de Radiação , Proteção Radiológica/instrumentação , Intensificação de Imagem Radiográfica/métodos , Radiografia/métodos , Reprodutibilidade dos Testes , Espalhamento de Radiação , Raios XRESUMO
BACKGROUND: Error within imaging measurements can be due to processing, magnification, measurement performance, or patient-specific factors. Previous length measurement studies based on radiographs have shown good intraclass correlation coefficients (ICCs) on single images; but have not assessed interimage distortion. In our study, "image distortion in biplanar slot scanning: technology-specific factors" we determined that there is minimal image distortion due to the image acquisition when using biplanar slot scanning. In this study, we aim to determine the role of patient-specific factors in image distortion, specifically evaluating interimage distortion. METHODS: Digital radiographs and biplanar slot scanner images were reviewed in 43 magnetically controlled growing rod (MCGR) patients. Fifty-five postoperative anteroposterior digital radiographs, 184 follow-up biplanar slot-scanner scanner posteroanterior and 76 biplanar slot-scanner scanner laterals were measured by 2 residents and 1 attending. The manufacturer reported average actuator diameter of 9.02 mm was used as our reference width. RESULTS: Overall, within image interobserver ICC were moderate to excellent (0.635 to 0.983), but the interimage ICCs were poor (0.332). Digital radiographs consistently overestimated the MCGR actuator width (mean=9.655) and biplanar slot-scanner scanner images underestimated it (mean=8.935). The measurement range was large with biplanar slot-scanner scanner posteroanterior (up to 15%) and lateral (22%) measurements and with digital radiographs (39%). Patients with abnormal muscle tone had higher degrees of measurement variability. CONCLUSIONS: We found that neither biplanar slot scanning nor digital radiography was precise or accurate. Digital radiographs consistently overestimated MCGR actuator width and biplanar slot scanning underestimated it. The poor ICC's within and between image subtypes and large standard error of measurement reflected a magnitude of distortion that needs to be accounted for when using length measurements clinically. Unlike the clinically insignificant error that we noted in our previous study "image distortion in biplanar slot scanning: technology-specific factors" (0.5% to 1.5% of the measurement), the error noted in this study (0.2% to 38.5% of the measurement) has the potential to be clinically significant. Patients who have abnormal muscle tone had larger measurement errors, likely stemming from motion during the slot scanning process. LEVEL OF EVIDENCE: Level III.
Assuntos
Erros de Diagnóstico/prevenção & controle , Precisão da Medição Dimensional , Intensificação de Imagem Radiográfica , Coluna Vertebral/diagnóstico por imagem , Criança , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Movimento , Posicionamento do Paciente , Cuidados Pré-Operatórios/métodos , Intensificação de Imagem Radiográfica/métodos , Intensificação de Imagem Radiográfica/normas , Reprodutibilidade dos Testes , Estudos Retrospectivos , Coluna Vertebral/cirurgiaRESUMO
AIM: To evaluate the effect of iso-osmolar contrast media (IOCM) at different tube voltages on image quality for abdominal computed tomography (CT) in paediatric patients. MATERIALS AND METHODS: The low osmolar contrast media (LOCM) group and IOCM group consisted of 101 and 102 CT examinations, respectively, in patients <18 years old. Images were reviewed retrospectively. Objective measurement of the contrast enhancement and noise were analysed and contrast-to-noise ratios (CNRs) of the abdominal aorta, portal vein, and liver were calculated. Four radiologists participated in subjective analysis using a four-point scale system to evaluate degrees of contrast enhancement, image noise, beam-hardening artefact, and overall image quality. Reader performance for correctly differentiating the two kinds of contrast media was evaluated. RESULTS: Regarding the objective measurement, contrast enhancement was significantly higher in the LOCM group (p<0.05). In subjective analysis, only CT using 120 kVp showed significantly stronger enhancement in the LOCM group (p=0.002), and sensitivity to differentiate the IOCM was 80.6%. Overall sensitivity and specificity for correctly differentiating IOCM were 57.1%, and 56.9%, respectively. CONCLUSION: The application of IOCM was found to be feasible for performing paediatric abdominopelvic CT with a low tube voltage protocol. Although objective measurements of contrast enhancement were significantly lower in the IOCM group, subjective contrast enhancement and image quality assessments were not statistically different between groups.
Assuntos
Meios de Contraste , Tomografia Computadorizada Multidetectores/normas , Abdome/diagnóstico por imagem , Adolescente , Aorta Abdominal/diagnóstico por imagem , Artefatos , Criança , Pré-Escolar , Estudos de Viabilidade , Feminino , Humanos , Fígado/diagnóstico por imagem , Masculino , Concentração Osmolar , Pelve/diagnóstico por imagem , Veia Porta/diagnóstico por imagem , Doses de Radiação , Intensificação de Imagem Radiográfica/métodos , Intensificação de Imagem Radiográfica/normas , Estudos Retrospectivos , Sensibilidade e Especificidade , Razão Sinal-RuídoRESUMO
BACKGROUND: Transthoracic echocardiography is the primary imaging modality for diagnosing cardiac conditions but medical education in this field is limited. We tested the hypothesis that a structured theoretical and supervised practical course of training in focused echocardiography in last year medical students results in a more accurate assessment and more precise calculation of left ventricular ejection fraction after ten patient examinations. METHODS: After a theoretical introduction course 25 last year medical students performed ten transthoracic echocardiographic examination blocks in postsurgical patients. Left ventricular function was evaluated both with an eye-balling method and with the calculated ejection fraction using diameter and area of left ventricles. Each examination block was controlled by a certified and blinded tutor. Bias and precision of measurements were assessed with Bland and Altman method. RESULTS: Using the eye-balling method students agreed with the tutor's findings both at the beginning (88%) but more at the end of the course (95.7%). The variation between student and tutor for calculation of area, diameter and ejection fraction, respectively, was significantly lower in examination block 10 than in examination block 1 (each p < 0.001). Students underestimated both the length and the area of the left ventricle at the outset, as complete imaging of the left heart in the ultrasound sector was initially unsuccessful. CONCLUSIONS: A structured theoretical and practical transthoracic echocardiography course of training for last year medical students provides a clear and measurable learning experience in assessing and measuring left ventricular function. At least 14 examination blocks are necessary to achieve 90% agreement of correct determination of the ejection fraction.
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Ecocardiografia/métodos , Intensificação de Imagem Radiográfica/normas , Radiologia/educação , Volume Sistólico/fisiologia , Estudantes de Medicina , Função Ventricular Esquerda/fisiologia , Ecocardiografia/instrumentação , Humanos , Período Pós-Operatório , Adulto JovemRESUMO
OBJECTIVE: To establish a set of evaluation system of digital radiography clinical value and provide foundation for the maturity assessment of digital radiography. METHODS: The evaluation system of clinical value of digital radiography was established by literature survey,expert consultation,and percentage weight method. RESULTS: The expert authority coefficients were 0.81 and 0.88,respectively.After two rounds of consultation,variation coefficients of each item ranged from 0 to 0.207,and the coefficient coordination were 0.599.The index system consisted of 5 first-level indexes and 12 second-level indexes.The weights of first-level indexes such as image quality,safety,usability,economic and social indicators share of the weight are 0.298,0.294,0.199,0.121 and 0.088 respectively. CONCLUSIONS: A completed and scientific evaluation system was established,which provides a scientific assessment tool for clinical value of digital radiography.
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Intensificação de Imagem Radiográfica , Técnica Delphi , Intensificação de Imagem Radiográfica/normasRESUMO
OBJECTIVE: To explore the effect of Pareto analysis on the investigation of DR (Digital Radiography) high fault rate. METHODS: The quality control team was established to analyze the causes of DR high fault rate by using the fault statistics of eight DR in our hospital for nearly three years,and to formulate and implement countermeasures,then compare them with the data after rectification. RESULTS: After three months of implementation,the number of DR faults in our hospital decreased from 130 times/quarter to 47 times/quarter,a year-on-year drop was 63.8%.Among them,the number of console faults decreased from 105 times/quarter to 25 times/quarter,a year-on-year drop was 76.2%,close to 80%. CONCLUSIONS: Pareto analysis is effective in reducing DR fault rate and is worthy of being promoted to other medical devices.
Assuntos
Intensificação de Imagem Radiográfica , Humanos , Intensificação de Imagem Radiográfica/instrumentação , Intensificação de Imagem Radiográfica/normasRESUMO
In this paper, the focus of technical review of the registration application data of digital Breast Tomosynthesis Mammography System was sorted out, so as to provide reference for researchers and manufacturers in China when applying for registration and preparation of such products.
Assuntos
Mamografia , Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , China , Humanos , Mamografia/instrumentação , Mamografia/normas , Intensificação de Imagem Radiográfica/normas , Fatores de RiscoRESUMO
BACKGROUND: Multi-site neuroimaging offer several benefits and poses tough challenges in the drug development process. Although MRI protocol and clinical guidelines developed to address these challenges recommend the use of good quality images, reliable assessment of image quality is hampered by the several shortcomings of existing techniques. METHODS: Given a test image two feature images are extracted. They are grayscale and contrast feature images. Four binary images are generated by setting four different global thresholds on the feature images. Image quality is predicted by measuring the structural similarity between appropriate pairs of binary images. The lower and upper limits of the quality index are 0 and 1. Quality prediction is based on four quality attributes; luminance contrast, texture, texture contrast and lightness. RESULTS: Performance evaluation on test data from three multi-site clinical trials show good objective quality evaluation across MRI sequences, levels of distortion and quality attributes. Correlation with subjective evaluation by human observers is ≥ 0.6. CONCLUSION: The results are promising for the evaluation of MRI protocols, specifically the standardization of quality index, designed to overcome the challenges encountered in multi-site clinical trials.
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Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética/normas , Intensificação de Imagem Radiográfica/normas , Algoritmos , Ensaios Clínicos como Assunto , Humanos , Sistema Métrico , Estudos Multicêntricos como Assunto , Neuroimagem/normasRESUMO
BACKGROUND: Radiology is an important aspect of medicine to which medical students often do not receive sufficient exposure. The aim of this project was to determine whether the integration of an innovative e-learning module on chest x-ray interpretation of the heart would enhance the radiological interpretive skills, and improve the confidence, of first year graduate entry medical students. METHODS: All first-year graduate entry (all students had a prior university degree) medical students at the University of Limerick (n = 152) during academic year 2015-16 were invited to participate in this study. An assessment instrument was developed which consisted of 5 radiological cases to be interpreted over a designated and supervised 15-min time period. Students underwent a pre-, mid- and post-intervention assessment of their radiology interpretative skills. An online e-module was provided following the pre-test and additional practice cases were provided following the mid-intervention test. Assessment scores and confidence levels were compared pre-, mid- and post-intervention. RESULTS: The overall performance (out of a total score of 25) for the 87 students who completed all three assessments increased from 13.2 (SD 3.36) pre-intervention to 14.3 (SD 2.97) mid-intervention to 15.8 (SD 3.40) post-intervention. This change over time was statistically significant (p < 0.001) with a medium effect size (eta-squared = 0.35). Increases from pre- to post-intervention were observed in each of the five areas assessed, although performance remained poor in diagnosis post-intervention. Of the 118 students who provided feedback after the intervention, 102 (86.4%) stated that they would recommend the resource to a colleague to improve their interpretative skills. CONCLUSIONS: This study suggests that early exposure to e-learning radiology modules is beneficial in undergraduate medical school curricula. Further studies are encouraged to assess how long the improvement may last before attrition.
Assuntos
Competência Clínica/estatística & dados numéricos , Educação de Graduação em Medicina , Intensificação de Imagem Radiográfica/normas , Interpretação de Imagem Radiográfica Assistida por Computador/estatística & dados numéricos , Radiografia Torácica , Radiologia/educação , Adulto , Competência Clínica/normas , Avaliação Educacional , Feminino , Humanos , Masculino , Variações Dependentes do Observador , Valor Preditivo dos Testes , Avaliação de Programas e Projetos de Saúde , Interpretação de Imagem Radiográfica Assistida por Computador/normas , Reprodutibilidade dos Testes , Estudantes de Medicina , Adulto JovemRESUMO
OBJECTIVE: To compare the diagnostic accuracy of medical-grade and calibrated consumer-grade digital displays for the detection of subtle bone fissures. METHODS: Three experienced radiologists assessed 96 digital radiographs, 40 without and 56 with subtle bone fissures, for the presence or absence of fissures in various bones using one consumer-grade and two medical-grade displays calibrated according to the DICOM-Grayscale Standard Display Function. The reference standard was consensus reading. Subjective image quality was also assessed by the three readers. Statistical analysis was performed using receiver operating characteristic analysis and by calculating the sensitivity, specificity, and Youden's J for each combination of reader and display. Cohen's unweighted kappa was calculated to assess inter-rater agreement. Subjective image quality was compared using the Wilcoxon signed-rank test. RESULTS: No significant differences were found for the assessment of subjective image quality. Diagnostic performance was similar across all readers and displays, with Youden's J ranging from 0.443 to 0.661. The differences were influenced more by the reader than by the display used for the assessment. CONCLUSION: No significant differences were found between medical-grade and calibrated consumer-grade displays with regard to their diagnostic performance in assessing subtle bone fissures. Calibrated consumer-grade displays may be sufficient for most radiological examinations. KEY POINTS: ⢠Diagnostic performance of calibrated consumer-grade displays is comparable to medical-grade displays. ⢠There is no significant difference with regard to subjective image quality. ⢠Use of calibrated consumer-grade displays could cut display costs by 60-80%.
Assuntos
Fraturas Ósseas/diagnóstico por imagem , Calibragem , Apresentação de Dados , Humanos , Variações Dependentes do Observador , Garantia da Qualidade dos Cuidados de Saúde , Curva ROC , Intensificação de Imagem Radiográfica/métodos , Intensificação de Imagem Radiográfica/normas , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X/métodos , Tomografia Computadorizada por Raios X/normasRESUMO
BACKGROUND: The Digital X-ray Radiogrammetry (DXR) method measures the cortical bone thickness in the shafts of the metacarpals and has demonstrated its relevance in the assessment of hand bone loss caused by rheumatoid arthritis (RA). The aim of this study was to validate a novel approach of the DXR method in comparison with the original version considering patients with RA. METHOD: The study includes 49 patients with verified RA. The new version is an extension of the BoneXpert method commonly used in pediatrics which has these characteristics: (1) It introduces a new technique to analyze the images which automatically validates the results for most images, and (2) it defines the measurement region relative to the ends of the metacarpals. The BoneXpert method measures the Metacarpal Index (MCI) at the metacarpal bone (II to IV). Additionally, the MCI is quantified by the DXR X-posure System. RESULTS: The new version correctly analyzed all 49 images, and 45 were automatically validated. The standard deviation between the MCI results of the two versions was 2.9% of the mean MCI. The average Larsen score was 2.6 with a standard deviation of 1.3. The correlation of MCI to Larsen score was -0.81 in both versions, and there was no significant difference in their ability to detect erosions. CONCLUSION: The new DXR version (BoneXpert) validated 92% of the cases automatically, while the same good correlation to RA severity could be presented compared to the old version.
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Artrite Reumatoide/diagnóstico por imagem , Densidade Óssea , Ossos Metacarpais/diagnóstico por imagem , Intensificação de Imagem Radiográfica/normas , Idoso , Artrite Reumatoide/fisiopatologia , Densidade Óssea/fisiologia , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Intensificação de Imagem Radiográfica/métodosRESUMO
BACKGROUND: Obstruction is a common cause of ventriculo-peritoneal shunt failure. Head computed tomography and plain x-ray examinations of shunt tubing ("shunt series") are routinely used in patients readmitted for reemerging symptoms but are of limited value. The validity of shunt series can be improved by applying contrast agent into the system (contrast-enhanced shunt series, a.k.a. a "shuntogram" or "shuntography"). We hypothesized that contrast-enhanced shunt series have a high predictive value for shunt revision surgeries. METHODS: We retrospectively re-evaluated 107 contrast-enhanced shunt series and reviewed the patient histories. We defined outcome parameters for calculating the utility of a pathological contrast-enhanced shunt series in predicting revision surgery. RESULTS: Of 107 contrast-enhanced shunt series, 41 examinations were positive for obstruction, mainly of the ventricular (36.5 %) and the peritoneal catheter (48.8 %). Within 30 days, 35 successful revision surgeries and 3 revision surgeries without resolution of symptoms were performed. In two cases the shunt tubing was found to be patent. Sixty-six negative examinations resulted in two revision surgeries, in addition to ten surgeries not attempting to restore patency. After 30 days, the specificity of contrast-enhanced shunt series for shunt failure identification was calculated at 92.8 %, the sensitivity at 94.7 %, the positive predictive value at 87.8 %, and the negative predictive value at 97.0 %. CONCLUSIONS: The contrast-enhanced shunt series method is a highly specific examination with a negative predictive value exceeding that of head computed tomography and plain shunt series. Compared to radionuclide marker studies, contrast-enhanced shunt series demonstrate better spatiotemporal resolution, enabling focused local surgical repair.
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Falha de Equipamento/estatística & dados numéricos , Intensificação de Imagem Radiográfica/métodos , Reoperação/estatística & dados numéricos , Tomografia Computadorizada por Raios X/métodos , Derivação Ventriculoperitoneal/estatística & dados numéricos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Intensificação de Imagem Radiográfica/normas , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/normas , Derivação Ventriculoperitoneal/efeitos adversosRESUMO
PURPOSE: Insufficient image contrast associated with radiation therapy daily setup x-ray images could negatively affect accurate patient treatment setup. We developed a method to perform automatic and user-independent contrast enhancement on 2D kilo voltage (kV) and megavoltage (MV) x-ray images. The goal was to provide tissue contrast optimized for each treatment site in order to support accurate patient daily treatment setup and the subsequent offline review. METHODS: The proposed method processes the 2D x-ray images with an optimized image processing filter chain, which consists of a noise reduction filter and a high-pass filter followed by a contrast limited adaptive histogram equalization (CLAHE) filter. The most important innovation is to optimize the image processing parameters automatically to determine the required image contrast settings per disease site and imaging modality. Three major parameters controlling the image processing chain, i.e., the Gaussian smoothing weighting factor for the high-pass filter, the block size, and the clip limiting parameter for the CLAHE filter, were determined automatically using an interior-point constrained optimization algorithm. RESULTS: Fifty-two kV and MV x-ray images were included in this study. The results were manually evaluated and ranked with scores from 1 (worst, unacceptable) to 5 (significantly better than adequate and visually praise worthy) by physicians and physicists. The average scores for the images processed by the proposed method, the CLAHE, and the best window-level adjustment were 3.92, 2.83, and 2.27, respectively. The percentage of the processed images received a score of 5 were 48, 29, and 18%, respectively. CONCLUSION: The proposed method is able to outperform the standard image contrast adjustment procedures that are currently used in the commercial clinical systems. When the proposed method is implemented in the clinical systems as an automatic image processing filter, it could be useful for allowing quicker and potentially more accurate treatment setup and facilitating the subsequent offline review and verification.
Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador/normas , Neoplasias Pulmonares/diagnóstico por imagem , Intensificação de Imagem Radiográfica/normas , Radiografia Torácica , Tomografia Computadorizada por Raios X/métodos , Automação , Humanos , Neoplasias Pulmonares/patologia , Raios XRESUMO
AIM: To compare digital images of conventional radiographs with the original radiographs for perceived clarity of periapical lesions and the quality of root canal treatment. MATERIALS AND METHODS: One hundred and four intraoral periapical radiographs of patients with endodontically treated teeth were randomly selected. The radiographs were digitized using an MD300 USB X-ray Reader. The digital images were transferred to an HP laptop. Three evaluators compared each conventional radiograph with the matching digital image. The images were ranked for clarity and assessed for diagnostic quality; data were analyzed using the Reliability Calculation "ReCal." Results. Both the digital images and conventional films had comparable clarity and diagnostic quality. Results indicated a moderate agreement between the evaluators. CONCLUSIONS: Conventional radiographs digitized using an MD300 USB X-ray Reader have similar clarity and diagnostic quality in comparison to the original radiographs.
Assuntos
Cavidade Pulpar/diagnóstico por imagem , Tecido Periapical/diagnóstico por imagem , Intensificação de Imagem Radiográfica/métodos , Radiografia Dentária/métodos , Humanos , Intensificação de Imagem Radiográfica/instrumentação , Intensificação de Imagem Radiográfica/normas , Radiografia Dentária/instrumentação , Radiografia Dentária/normas , Tratamento do Canal Radicular/normasRESUMO
When The Joint Commission updated its Requirements for Diagnostic Imaging Services for hospitals and ambulatory care facilities on July 1, 2015, among the new requirements was an annual performance evaluation for acquisition workstation displays. The purpose of this work was to evaluate a large cohort of acquisition displays used in a clinical environment and compare the results with existing performance standards provided by the American College of Radiology (ACR) and the American Association of Physicists in Medicine (AAPM). Measurements of the minimum luminance, maximum luminance, and luminance uniformity, were performed on 42 acquisition displays across multiple imaging modalities. The mean values, standard deviations, and ranges were calculated for these metrics. Additionally, visual evaluations of contrast, spatial resolution, and distortion were performed using either the Society of Motion Pictures and Television Engineers test pattern or the TG-18-QC test pattern. Finally, an evaluation of local nonuniformities was performed using either a uniform white display or the TG-18-UN80 test pattern. Displays tested were flat panel, liquid crystal displays that ranged from less than 1 to up to 10 years of use and had been built by a wide variety of manufacturers. The mean values for Lmin and Lmax for the displays tested were 0.28 ± 0.13 cd/m2 and 135.07 ± 33.35 cd/m2, respectively. The mean maximum luminance deviation for both ultrasound and non-ultrasound displays was 12.61% ± 4.85% and 14.47% ± 5.36%, respectively. Visual evaluation of display performance varied depending on several factors including brightness and contrast settings and the test pattern used for image quality assessment. This work provides a snapshot of the performance of 42 acquisition displays across several imaging modalities in clinical use at a large medical center. Comparison with existing performance standards reveals that changes in display technology and the move from cathode ray tube displays to flat panel displays may have rendered some of the tests inappropriate for modern use.
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Apresentação de Dados/normas , Diagnóstico por Imagem/instrumentação , Diagnóstico por Imagem/normas , Intensificação de Imagem Radiográfica/instrumentação , Intensificação de Imagem Radiográfica/métodos , Processamento de Sinais Assistido por Computador/instrumentação , Guias como Assunto , Humanos , Intensificação de Imagem Radiográfica/normas , Padrões de Referência , Interface Usuário-ComputadorRESUMO
As the use of diagnostic X-ray equipment with flat panel detectors (FPDs) has increased, so has the importance of proper management of FPD systems. To ensure quality control (QC) of FPD system, an easy method for evaluating FPD imaging performance for both stationary and moving objects is required. Until now, simple rotatable QC phantoms have not been available for the easy evaluation of the performance (spatial resolution and dynamic range) of FPD in imaging moving objects. We developed a QC phantom for this purpose. It consists of three thicknesses of copper and a rotatable test pattern of piano wires of various diameters. Initial tests confirmed its stable performance. Our moving phantom is very useful for QC of FPD images of moving objects because it enables visual evaluation of image performance (spatial resolution and dynamic range) easily.
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Imagens de Fantasmas , Controle de Qualidade , Intensificação de Imagem Radiográfica/instrumentação , Ecrans Intensificadores para Raios X/normas , Movimento (Física) , Intensificação de Imagem Radiográfica/normasRESUMO
The imaging department can be instrumental in contributing to a healthcare facility's ability to succeed in this new era of competition. Advances in DR technology can improve patient perceptions in the imaging department by improving efficiencies and outcomes which, in turn, can ultimately bolster overall HCAHPS scores. Specific areas for improved scores by utilization of DR include nurse communication, doctor communication, pain management, and communication about medication. Value based purchasing brought with it a mandate for hospitals to track key metrics, which requires an investment in time, tools, and human resources. However, this mandate also presents hospitals and imaging departments, with an opportunity to leverage those very metrics to better market their facilities.
Assuntos
Melhoria de Qualidade , Intensificação de Imagem Radiográfica/normas , Comunicação , Humanos , Estudos de Casos Organizacionais , Satisfação do Paciente , Aquisição Baseada em ValorRESUMO
The International Classification of Radiographs of Pneumoconioses is the scheme worked out by the International Labour Office in Geneva (ILO), to register radiographic chest abnormalities in a well-ordered, reproducible and comparable way. It is used for diagnosing abnormalities caused by dust exposure. Guidelines for the use of the ILO International Classification of Radiographs of Pneumoconioses contain detailed information and recommendations on how to use the classification, as well as how the chest X-ray examination should be performed and recorded. To facilitate the diagnosis of observed abnormalities the classification is completed by the set of standard radiograms illustrating typical irregularities referring to lungs and pleura, included in the classification. The article presents the key information on classification and the most important amendments adopted in the 2000 and 2011 ILO guidelines revisions. These changes refer to radiographs quality assessment, the way of presenting abnormalities registered in standard radiographs (QUAD set, digital images) and registration of failures not related to dust exposure. Particularly important complements result from the development of radiological imaging techniques. They are concerned about the classification of radiographic images of the chest recorded digitally. Med Pr 2016;67(6):833-837.
Assuntos
Classificação Internacional de Doenças , Doenças Profissionais , Medicina do Trabalho , Pneumoconiose , Intensificação de Imagem Radiográfica , Humanos , Classificação Internacional de Doenças/normas , Doenças Profissionais/classificação , Doenças Profissionais/diagnóstico por imagem , Medicina do Trabalho/normas , Pneumoconiose/classificação , Pneumoconiose/diagnóstico por imagem , Intensificação de Imagem Radiográfica/normas , Radiologia/normas , Reprodutibilidade dos TestesRESUMO
OBJECTIVE: The purpose of this study was to ascertain if standardized radiologic reporting for appendicitis imaging increases diagnostic accuracy. MATERIALS AND METHODS: We developed a standardized appendicitis reporting system that includes objective imaging findings common in appendicitis and a certainty score ranging from 1 (definitely not appendicitis) through 5 (definitely appendicitis). Four radiologists retrospectively reviewed the preoperative CT scans of 96 appendectomy patients using our reporting system. The presence of appendicitis-specific imaging findings and certainty scores were compared with final pathology. These comparisons were summarized using odds ratios (ORs) and the AUC. RESULTS: The appendix was visualized on CT in 89 patients, of whom 71 (80%) had pathologically proven appendicitis. Imaging findings associated with appendicitis included appendiceal diameter (odds ratio [OR] = 14 [> 10 vs < 6 mm]; p = 0.002), periappendiceal fat stranding (OR = 8.9; p < 0.001), and appendiceal mucosal hyperenhancement (OR = 8.7; p < 0.001). Of 35 patients whose initial clinical findings were reported as indeterminate, 28 (80%) had appendicitis. In this initially indeterminate group, using the standardized reporting system, radiologists assigned higher certainty scores (4 or 5) in 21 of the 28 patients with appendicitis (75%) and lower scores (1 or 2) in five of the seven patients without appendicitis (71%) (AUC = 0.90; p = 0.001). CONCLUSION: Standardized reporting and grading of objective imaging findings correlated well with postoperative pathology and may decrease the number of CT findings reported as indeterminate for appendicitis. Prospective evaluation of this reporting system on a cohort of patients with clinically suspected appendicitis is currently under way.