Mobile Chest Radiography Research Articles

Development of Augmented Reality-Based Radiation Protection Application for Healthcare Professionals

Background: Radiodiagnosis is widely performed in medical institutions. All medical professionals, including nurses, are at risk of radiation exposure. This study developed an educational application for radiation medical professionals to visualize the distribution of scattered radiation using augmented reality.Materials and Methods: A Monte Carlo simulation code was used to simulate mobile chest and abdominal radiography. The calculation results were incorporated into an augmented reality application. The results of the Monte Carlo calculations were validated by comparing them with radiation measurements. An augmented reality application for tablet devices was developed in Unity that visualizes the scattered radiation dose.Results and Discussion: The application was developed by visualizing the distribution of scattered radiation in mobile radiography in augmented reality in three-dimensional real space. The calculation results were validated, and the error between the displayed radiation dose values and the measured radiation dose values was generally less than 10%.Conclusion: The developed application allows users to overlay quantitative values of imperceptible radiation exposure doses onto any real-world environment. This enables users to intuitively understand the relationship between the distance from a radiation source and the received dose, thereby contributing to a better understanding of radiation protection in clinical settings.

Evaluation of Virtual Grid processed clinical pelvic radiographs.

A physical scatter grid is not often used in pelvic bedside examinations. However, multiple studies regarding scatter correction software (SC SW) are available for mobile chest radiography but the results are unclear for pelvic radiography. We evaluated SC SW of Fujifilm (Virtual Grid) on gridless pelvic radiographs obtained from a human Thiel-embalmed body to investigate the potential of Virtual Grid in pelvic bedside examinations. Gridless, Virtual Grid, and physical grid pelvic radiographs of a female Thiel-embalmed body were collected with a broad range of tube loads. Different software (SW) grid ratios-6:1, 10:1, 13:1, 17:1, and 20:1-were applied on the gridless radiographs to investigate the image quality (IQ) improvement of 13 IQ criteria in a visual grading analysis (VGA) setup. Gridless radiograph scores are significantly lower (p<0.001) than Virtual Grid and physical grid scores obtained with the same tube load. Virtual Grid radiographs score better than gridless radiographs obtained with a higher tube load which makes a dose reduction possible. The averaged ratings of the IQ criteria processed with different SW ratios increase with increasing SW grid ratios. However, no statistically significant differences were found between the SW grid ratios. The scores of the physical grid radiographs are higher than those of the Virtual Grid radiographs when they are obtained with the same tube load. We conclude that Virtual Grid with an SW ratio of 6:1 improves the IQ of gridless pelvic radiographs in such a manner that a dose reduction is possible. However, physical grid radiograph ratings are higher compared to those of Virtual Grid radiographs.

Evaluation of the Distribution of Spatial Scattered Radiation Dose in Bedside Dynamic Chest Radiography

The purpose of this study was to determine the distribution of spatial scattered radiation during mobile dynamic chest radiography and to develop protective measures. We measured the spatial scattered radiation, assuming both mobile chest radiography and mobile dynamic chest radiography. We placed the chest phantom on a stretcher. Gatch-up angles were varied from 75°(seated position), 35°(semi-seated position), and 0°(supine position). We measured spatial scattered radiation using the ionization chamber survey meter. The height of the measurement points was 100 cm and 150 cm, assuming the position of the abdomen and lens. We also measured spatial scattered radiation using the radiation shielding screen. Spatial scattered radiation dose in mobile dynamic chest radiography was approximately five to six times higher than in mobile chest radiography. In the seated position, the spatial scattered radiation dose was about 1.5 times higher on the caudal side of the phantom compared to the cranial side. Behind the radiation shielding screen, the spatial scattered radiation dose decreased significantly. If the examination is performed in a seated position, the radiological technologist can reduce exposure by moving to the patient's head side. Radiation shielding screens are very effective in reducing radiation exposure in mobile dynamic chest radiography.

Feasibility of new patient dose management tool in digital radiography: Using clinical exposure index data of mobile chest radiography in a large university hospital

The clinical anteroposterior (AP) chest images taken with a mobile radiography system were analyzed in this study to utilize the clinical exposure index (EI) as a patient dose-monitoring tool. The digital imaging and communications in medicine header of 6048 data points exposed under the 90 kVp and 2.5 mAs were extracted using Python for identifying the distribution of clinical EI. Even under the same exposure conditions, the clinical EI distribution was 137.82–4924.38. To determine the cause, the effect of a patient's body shape on EI was confirmed using actual clinical chest AP image data binarized into 0 and 255-pixel values using Python. As a result, the relationship between the direct X-ray area of the chest AP image, the higher the clinical EI, the larger the rate of the direct X-ray area. A conversion equation was also derived to infer entrance surface dose through clinical EI based on the patient thickness. This confirmed the possibility of directly monitoring patient dose through EI without a dosimeter in real-time. Therefore, to use the clinical EI of the mobile radiography system as a patient dose-monitoring tool, the derivation method of clinical EI considers several factors, such as the relationship between patient factors.

Establishing weight-based diagnostic reference levels for neonatal chest X-rays

IntroductionAs weights among neonates can vary from <900 g to >2.5 kg, weight-based Diagnostic Reference Levels (DRLs) specific to the neonatal intensive care unit (NICU) are essential. Repeated radiation exposure to this sensitive patient group raises concerns regarding high cumulative radiation doses and the potential for long-term health detriment. This study aimed to establish weight-based DRLs for neonates undergoing mobile chest radiography (CXR) in the NICU. MethodsNeonates were classified into three discrete groups; <1000, 1000–2500 and >2500 g. Data were collected prospectively over three months; 95 DAP values were collected, and five were excluded due to poor technique, leaving 90 patients that met the inclusion criteria for mobile CXR in the NICU. Dose-area-product (DAP) in mGycm2, the peak kilovoltage (kVp) and the product of tube current and exposure time (mAs) were retrieved from the Picture Archiving and Communication System (PACS). Images and radiological reports were also analysed to confirm diagnostic image quality (IQ). Local DRLs (LDRLs) were derived using the median DAP, and national DRLs were suggested using the 3rd quartile value. ResultsThe proposed LDRLs for neonates weighing <1000 g was 2.7 mGycm2, for neonates weighing between 1000 g and 2500 g, it was 3.7 mGycm2, and for neonates weighing >2500 g it was 6.6 mGycm2. The radiation dose received by the 90 (100%) neonates included in the study fell below 11.4 mGycm2; of these, 82% of the DAP values fell below the study institution's existing LDRL of 7.25 mGycm2. ConclusionWeight-based DRLs provide crucial information on doses to this specific radiation-sensitive group. This work recommends using weight-based categories for DRLs and serves as a benchmark for neonatal CXR standardisation and optimisation. Implications for practiceThe proposed weight-based DRLs can be adopted for neonates’ locally, nationally and internationally.

Active Case Finding Using Mobile Chest Radiography among Homeless People with Pulmonary Tuberculosis in Osaka City, Japan, 2013-2019.

Mobile digital chest radiography (CR) is a commonly used method for pulmonary tuberculosis (PTB) screening among homeless people in Nishinari District, Osaka City, Japan. We investigated mobile CR screening (MCS) to calculate the case-finding rate of culture-confirmed PTB among homeless examinees in Nishinari District from 2013 to 2019. PTB was defined as a sputum culture-confirmed case. Examinees with culture-confirmed PTB >90 days after MCS were defined as having no progression to active tuberculosis when undergoing MCS. We collected participants' information, including their name, date of birth, age, sex, date of MCS, CR classification (whether the abnormal CR result required further investigation), date of PTB diagnosis, and sputum smear results. Of 10,111 homeless people, 175 (1.7%) with abnormal CR results underwent further investigation at medical facilities. Of those with abnormal CR results, 22 (0.22%) were diagnosed with culture-positive PTB within 90 days of MCS. Of 22 PTB cases with culture-positive results, 13 (59.1%) were smear-positive. We found that MCS contributed to the detection of PTBs with a lower smear-positive rate among patients with PTB analyzed by MCS compared with all culture-confirmed PTB cases in Nishinari District.

Penuras Terbitan Gaussian Berorientasi untuk Peruasan Imej Paru-Paru Radiograf Mesin Pegun dan Mudah Alih

Unsupervised lung segmentation method is one of the mandatory processes in order to develop a Content Based Medical Image Retrieval System (CBMIRS) of CXR. There is limited study found on segmentation of mobile chest radiographs, that is relatively important especially for very sick patients whenever their radiographs will be taken using portable X-Ray machine.The purpose of the study is to present a solution for lung segmentation of standard and mobile chest radiographs using fully automated unsupervised method, based on oriented Gaussian derivatives filter with seven orientations, combined with Fuzzy C-Means clustering and thresholding to refine the lung region. A new algorithm to automatically generate a threshold value for each Gaussian response is also proposed. The algorithms are applied to both PA and AP chest radiographs from both public JSRT and private datasets from collaborative hospital. Two pre-processing blocks are introduced to standardize the images from different machines. Comparisons with the previous works found in the literature on JSRT dataset shows that our method gives a reasonably good result. Performance measures (accuracy, F-score, precision, sensitivity and specificity) for the segmentation of lung in public JSRT dataset are above 0.90 except for the overlap measure is 0.87. The median of overlap score for the private image database is 0.83 (standard machine) and 0.75 (mobile machines). The algorithm is also fast, with the average execution time of 12.5s. Our proposed method is fully automated, unsupervised, with no training or learning stage is necessary to segment the lungs taken using both a standard and mobile machines, and useful for the application of the CBMIRS.

Development of a radiopaque tiltmeter to improve reproducibility for Fowler's position on chest radiography

IntroductionWe have developed a novel radiopaque tiltmeter (ROT) that can indicate patient tilt during a radiography examination and display it on X-ray images. This study evaluated the effect of variation of patient tilt on the reproducibility of Fowler's position for chest radiography and the accuracy of the ROT. MethodsWe evaluated the reproducibility of Fowler's position based on changes from the first day in the central venous catheter (CVC) tip position and the cardiothoracic ratio (CTR) with and without a digital tiltmeter to verify its efficacy in patients who underwent mobile chest radiography. The ROT contains radiopaque liquid consisting of white barium sulfate solution and oil and has a scale bar of 15°–75° with increments of 15° to indicate ROT tilt. The ROT tilt was increased from 10° to 80° in increments of 10°. We then evaluated (1) the difference between the ROT tilt and the tilt measured with a digital tiltmeter, and (2) the ROT tilt displayed on the X-ray image. ResultsWith regard to reproducibility in Fowler's position, changes in the CVC tip position were 2.8 ± 3.9 mm and 10.7 ± 10.6 mm with and without the tiltmeter, respectively (p < 0.05) and the respective rates of change in the CTR were 0.7% ± 0.6% and 4.0% ± 2.1% (p < 0.05). Differences between the ROT tilt and the tilt measured by the digital tiltmeter were within ±2.5°. All ROT tilts displayed on the X-ray images were recognized exactly as each tilt. ConclusionOur novel ROT had the potential to accurately indicate patient tilt during chest radiography, which could be helpful in terms of reproducibility and precise follow-up. Implications for practiceUse of the ROT for determination of patient tilt can improve reproducibility in Fowler's position, allowing more accurate serial X-ray imaging.

Spatially targeted digital chest radiography to reduce tuberculosis in high-burden settings: A study of adaptive decision making

BackgroundSpatially-targeted approaches to screen for tuberculosis (TB) could accelerate TB control in high-burden populations. We aimed to estimate gains in case-finding yield under an adaptive decision-making approach for spatially-targeted, mobile digital chest radiography (dCXR)-based screening in communities with varying levels of TB prevalence. MethodsWe used a Monte-Carlo simulation model to simulate a spatially-targeted screening intervention in 24 communities with TB prevalence estimates derived from a large community-randomized trial. We implemented a Thompson sampling algorithm to allocate screening units based on Bayesian probabilities of local TB prevalence that are continuously updated during weekly screening rounds. Four mobile units for dCXR-based screening and subsequent Xpert Ultra-based testing were allocated among the communities during a 52-week period. We estimated the yield of bacteriologically-confirmed TB per 1000 screenings comparing scenarios of spatially-targeted and untargeted resource allocation. ResultsWe estimated that under the untargeted scenario, an expected 666 (95% uncertainty interval 522–825) TB cases would be detected over one year, equivalent to 8.9 (7.5–10.3) per 1000 individuals screened. Allocating the screening units to the communities with the highest (prior-year) cases notification rates resulted in an expected 760 (617−926) TB cases detected, 10.1 (8.6–11.8) per 1000 screened. Adaptive, spatially-targeted screening resulted in an expected 1241 (995–1502) TB cases detected, 16.5 (14.5–18.7) per 1000 screened. Numbers of dCXR-based screenings needed to detect one additional TB case declined during the first 12–14 weeks as a result of Bayesian learning. ConclusionWe introduce a spatially-targeted screening strategy that could reduce the number of screenings necessary to detect additional TB in high-burden settings and thus improve the efficiency of screening interventions. Empirical trials are needed to determine whether this approach could be successfully implemented.

Development of an application to visualise the spread of scattered radiation in radiography using augmented reality

As radiation is widely used in medical institutions, the lack of radiation protection education for health workers increases the risk of radiation exposure. The purpose of this study is to develop an application for radiation medical personnel that visualises the distribution of scattered radiation by using augmented reality (AR). The irradiation conditions for mobile chest and pelvic radiography were simulated using Monte Carlo simulations (Particle and Heavy Ion Transport code System). Monte Carlo results were verified using physical measurements. The behaviour of scattered radiation was displayed three-dimensionally in virtual reality using ParaView. Subsequently, an application to visualise scattered rays was developed in Unity for tablet devices. An application with a sense of reality was developed by visualising the scattered radiation distribution of a mobile imaging in a real space in AR in a three-dimensional size, which is close to the actual size. The radiation dose could be estimated at any position and the behaviour of scattered radiation became easier to understand.

To repeat or not to repeat: Radiologists demonstrated more decisiveness than their fellow radiographers in reducing the repeat rate during mobile chest radiography

IntroductionRadiologists and radiographers play a complementary role in providing an optimal image quality with decrease radiation dose and proper diagnosis during chest radiographs. We aim Investigate years of experience among radiologists and radiographers on perception of image quality and its impact on repeat rate when evaluating portable pediatric chest radiographs. MethodsIRB approved retrospective study consisted of randomly selected images (n = 131) of pediatric portable chest radiographs. Images were blindly assessed by four radiologists and four radiographers. Readers were asked to assess qualitative and quantitative image quality by rating: image quality, decision to repeat and image technique. All data was compared employing Pearson's Correlation, Visual grading characteristic (VGC) and Cohens' kappa analyses. ResultsImage quality: Radiologists (88.4%) rated images as excellent significantly more than radiographers (11.6%), and radiographers (90.1%) as poor significantly more than radiologists (9.9%) (p < 0.05). Repeat: Radiologists (57%) decided not to repeat images significantly more than radiographers (43%) (p < 0.05). Image technique: Radiologists rated images as acceptable (65%) and excellent (97.7%) significantly more than radiographers (35% and 2.3% respectively) (p < 0.05), whereas radiographers (84%) assessed image technique as poor significantly more than radiologists (16%) (p < 0.05). VGC: radiographers had slightly better qualitative evaluation of image quality than radiologists. An association between image quality (p < 0.002) and repeat decision (p < 0.044) with years of experience was established when comparing years of experience with image assessment rubric, while no association was noted with image technique (p < 0.9). ConclusionRadiologists demonstrated more decisiveness than their fellow radiographers in reducing the repeat rate of portable pediatric chest radiographs. Interestingly, years of experience only seem to affect image technique and image quality assessment among radiologists. Implications for practiceContinuous education of radiographers and close collaboration with radiologists is crucial to achieve optimal image quality and low radiation doses.

Modifications to mobile chest radiography technique during the COVID-19 pandemic – implications of X-raying through side room windows

IntroductionModifications to common radiographic techniques have resulted from the challenges presented by the COVID-19 pandemic. Reports exist regarding the potential benefits of undertaking mobile radiography through side room windows. The aim of this study was to evaluate the impact on image quality and exposure factors when undertaking such examinations. MethodsA phantom based study was undertaken using a digital X-ray room. Control acquisitions, using a commercially available image quality test tool, were performed using standard mobile chest radiography acquisition factors. Image quality (physical and visual), incidence surface air kerma (ISAK), Exposure Index (EI) and Deviation Index (DI) were recorded. Image quality and radiation dose were further assessed for two additional (experimental) scenarios, where a side room window was located immediately adjacent to the exit port of the light beam diaphragm. The goal of experimental scenario one was to modify exposure factors to maintain the control ISAK. The goal of experimental scenario two was to modify exposure factors to maintain the control EI and DI. Dose and image quality data were compared between the three scenarios. ResultsTo maintain the pre-window (control) ISAK (76 μGy), tube output needed a three-fold increase (90 kV/4 mAs versus 90 kV/11.25 mAs). To maintain EI/DI a more modest increase in tube output was required (90 kV/8 mAs/ISAK 54 μGy). Physical and visual assessments of spatial resolution and signal-to-noise ratio were indifferent between the three scenarios. There was a slight statistically significant reduction in contrast-to-noise ratio when imaging through the glass window (2.3 versus 1.4 and 1.2; P = 0.005). ConclusionUndertaking mobile X-ray examinations through side room windows is potentially feasible but does require an increase in tube output and is likely to be limited by minor reductions in image quality. Implications for practiceMobile examinations performed through side room windows should only be used in limited circumstances and future clinical evaluation of this technique is warranted.

Initial data from an experiment to implement a safe procedure to perform PA erect chest radiographs for COVID-19 patients with a mobile radiographic system in a “clean” zone of the hospital ward

IntroductionWith the current Covid-19 pandemic, general wards have been converted into cohort wards for Covid-19 patients who are stable and ambulant. A 2-radiographer mobile radiography team is required to perform bedside Chest X-rays (CXR) for these patients. Hospital guidelines require both radiographers to be in full Personal Protective Equipment (PPE) throughout the image acquisition process and the mobile radiographic unit needs to be disinfected twice after each case. This affects the efficiency of the procedure and an increase usage of limited PPE resources. This study aims to explore the feasibility of performing mobile chest radiography with the mobile radiographic unit in a “clean” zone of the hospital ward. MethodsAn anthropomorphic body phantom was used during the test. With the mobile radiographic unit placed in a “clean” zone, the phantom and the mobile radiographic unit was segregated by the room door with a clear glass panel. The test was carried out with the room door open and closed. Integrated radiation level and patient dose were measured. A consultant radiologist was invited to review and score all the images acquired using a Barco Medical Grade workstation. The Absolute Visual Grading Analysis (VGA) scoring system was used to score these images. ResultsA VGA score of 4 was given to all the 40 test images, suggesting that there is no significant differences in the image quality of the images acquired using the 2 different methods. Radiation exposure received by the patient at the highest kV setting through the glass is comparable to the regular CXR on patient without glass panel at 90 kV, suggesting that there is no significant increase in patient dose. ConclusionThe result suggests that acquiring CXR with the X-ray beam attenuating through a glass panel is a safe and feasible way of performing CXR for COVID-19 patients in the newly converted COVID wards. This will allow the mobile radiographic unit as well as one radiographer to be completely segregated from the patient. Implications for practiceThis new method of acquiring CXR in an isolation facility set up requires a 2-Radiographer mobile radiography team, and is applicable only for patients who are generally well and not presented with any mobility issues. It is also important to note that a clear glass panel must be present in the barriers set up for segregation between the “clean” zone and patient zone in order to use this new method of acquiring CXR.

Multidisciplinary Development of Mobile Radiography Guidelines Reduced the Number of Inappropriate Mobile Exams in Patients Receiving Chest Radiographs in British Columbia.

To decrease the number of mobile chest radiograph requests for inpatients in British Columbia who are medically able to tolerate transport to the main department by introducing and implementing request criteria. Concerns regarding inappropriate mobile exam requests in patients receiving chest radiography were surveyed at 28 medical imaging sites. In response, a multidisciplinary team composed a set of mobile radiography request guidelines incorporating feedback from all sites. These were successfully implemented along with in-person education to 21 sites. The number of adult annual mobile chest radiographs was tracked from 2014 to 2018, and informal feedback was obtained from participating sites. The percentage of mobile chest radiographs of all chest radiographs performed between 2014 and 2018 decreased by 3.2%, while the total number of all chest radiographs performed during this time, including both departmental and mobile, increased by 1.9%. Sites reported positive engagement with the initiative and expressed need for ongoing education to optimize its effect. Implementation of request guidelines with in-person education helped to reduce inappropriate mobile exams in patients receiving chest radiographs in British Columbia between 2014 and 2018. These guidelines promote patient safety through reduced radiation exposure, empower radiographers to mitigate inappropriate requests, and help to optimize use of limited hospital resources by reducing inappropriate mobile exams where routine departmental exams are more suitable.

Systematic Screening of Tuberculosis Using Mobile Digital Chest Radiography in Sabah

Background: Chest radiography, or chest X-ray (CXR), is not only an important tool for triaging and screening for pulmonary tuberculosis (TB) but is also useful in aiding diagnosis when pulmonary TB cannot be confirmed bacteriologically. Sabah is a state with high TB burden with the incidence rate of 124/100,000 population in 2015. Access to chest radiography is limited in many settings in Sabah. In 2016, the TB and Leprosy Control Unit of Sabah State Health Department started systematic screening for TB with the help of a mobile digital X-ray unit. &#x0D; Keywords: tuberculosis, systematic screening, mobile digital chest radiography

Mobile miniature X-ray evaluation and pneumoconiosis: the role of the Clinica del Lavoro in Milan (1941-1948)

«Mobile miniature X-ray evaluation and pneumoconiosis: the role of the Clinica del Lavoro in Milan (1941-1948)». Since the end of the 19th century, X-rays have been used to detect lung diseases. In Italy, 207,096 miniature chest radiographs were taken from 1941 to 1948. Traditional radiographs gave better results, but miniature chest radiographs were useful for screening. Indeed, the development of mobile miniature chest radiography units resulted in an improvement in mass X-rays screening for the detection of penumoconiosis. These mobile miniature units were mounted on a bus chassis, a solution that allowed to easily reach workers. The authors analyze some models of X-ray wagon units used by the “Clinica del Lavoro” in Milan in the 1950s. From the point of view of medical museology, the preservation of these devices requires appropriate spaces.

Optimisation of radiation dose and image quality in mobile neonatal chest radiography

PurposeTo optimise the radiation dose and image quality for chest radiography in the neonatal intensive care unit (NICU) by increasing the mean beam energy. MethodsTwo techniques for the acquisition of NICU AP chest X-ray images were compared for image quality and radiation dose. 73 images were acquired using a standard technique (56 kV, 3.2 mAs and no additional filtration) and 90 images with a new technique (62 kV, 2 mAs and 2 mm Al filtration). The entrance surface air kerma (ESAK) was measured using a phantom and compared between the techniques and against established diagnostic reference levels (DRL). Images were evaluated using seven image quality criteria independently by three radiologists. Images quality and radiation dose were compared statistically between the standard and new techniques. ResultsThe maximum ESAK for the new technique was 40.20 μGy, 43.7% of the ESAK of the standard technique. Statistical evaluation demonstrated no significant differences in image quality between the two acquisition techniques. ConclusionsBased on the techniques and acquisition factors investigated within this study, it is possible to lower the radiation dose without any significant effects on image quality by adding filtration (2 mm Al) and increasing the tube potential. Such steps are relatively simple to undertake and as such, other departments should consider testing and implementing this dose reduction strategy within clinical practice where appropriate.

Lung segmentation on standard and mobile chest radiographs using oriented Gaussian derivatives filter.

BackgroundUnsupervised lung segmentation method is one of the mandatory processes in order to develop a Content Based Medical Image Retrieval System (CBMIRS) of CXR. The purpose of the study is to present a robust solution for lung segmentation of standard and mobile chest radiographs using fully automated unsupervised method.MethodsThe novel method is based on oriented Gaussian derivatives filter with seven orientations, combined with Fuzzy C-Means (FCM) clustering and thresholding to refine the lung region. In addition, a new algorithm to automatically generate a threshold value for each Gaussian response is also proposed. The algorithms are applied to both PA and AP chest radiographs from both public JSRT dataset and our private datasets from collaborative hospital. Two pre-processing blocks are introduced to standardize the images from different machines. Comparisons with the previous works found in the literature on JSRT dataset shows that our method gives a reasonably good result. We also compare our algorithm with other unsupervised methods to provide fairly comparative measures on the performances for all datasets.ResultsPerformance measures (accuracy, F-score, precision, sensitivity and specificity) for the segmentation of lung in public JSRT dataset are above 0.90 except for the overlap measure is 0.87. The standard deviations for all measures are very low, from 0.01 to 0.06. The overlap measure for the private image database is 0.81 (images from standard machine) and 0.69 (images from two mobile machines). The algorithm is fully automated and fast, with the average execution time of 12.5 s for 512 by 512 pixels resolution.ConclusionsOur proposed method is fully automated, unsupervised, with no training or learning stage is necessary to segment the lungs taken using both a standard machine and two different mobile machines. The proposed pre-processing blocks are significantly useful to standardize the radiographs from mobile machines. The algorithm gives good performance measures, robust, and fast for the application of the CBMIRS.

Protocols and guidelines for mobile chest radiography in Irish public hospitals

BackgroundThe mobile chest radiograph is a highly variable examination, in both technique and setting. Protocols and guidelines are one method by which examinations can be standardised, and provide information when one is unsure how to proceed. This study was undertaken to investigate the existence of protocols and guidelines available for the mobile chest radiograph, to establish their nature and compare them under a variety of headings. MethodologyA postal survey was administered to the Radiography Service Managers in the public hospitals under the governance of the Health Service Executive (HSE) in Ireland. The survey contained questions regarding hospital demographics, contents of existing protocols or guidelines, and why a protocol or guideline was not in place, if this was the case. ResultsThe response rate to the survey was 62% (n = 24). Those that had a specific protocol in place amounted to 63% (n = 15), 71% (n = 17) had a specific guideline, and 63% (n = 15) had both. Twenty nine percent (n = 7) had no specific protocol/guideline in place. Scientific research (88%, n = 15) and radiographer experience (82%, n = 14) were the most common sources used to inform protocols and guidelines. ConclusionsThere are protocols and guidelines available to radiographers for mobile chest radiography in the majority of public hospitals in Ireland. The nature of the protocols and guidelines generally coincides with the HSE guidance regarding what sources of information should be used and how often they should be updated.

Active case finding for pulmonary tuberculosis using mobile digital chest radiography: an observational study

Mobile digital chest radiography (CXR) is used routinely to screen for pulmonary tuberculosis (PTB) in London among homeless populations, persons accessing drug treatment services and prisoners. 1) To establish the sensitivity and specificity of mobile digital CXR, and 2) to test the hypothesis that actively identified cases have reduced odds of sputum smear positivity vs. those presenting passively to health care services from the same populations. Sensitivity and specificity were calculated using a gold standard comparator of culture-confirmed cases of PTB reported to the national surveillance system within 90 days of screening. Logistic regression was used to determine whether actively detected cases had reduced odds of smear positivity compared to passively detected cases after adjustment for confounding. The intervention had a sensitivity of 81.8% (95%CI 64.5-93.0) and a specificity of 99.2% (95%CI 99.1-99.3). After adjusting for confounding, there was evidence that cases identified through screening were less likely to be smear-positive than passively identified cases (OR 0.34, 95%CI 0.14-0.85; likelihood ratio test P = 0.022). Digital CXR achieves a high level of sensitivity and specificity in an operational setting; targeted mobile radiographic screening can reduce the risk of onward transmission by identifying cases before they become infectious.