Clinical utility of postprocessed low-dose radiographs in skeletal imaging.

OBJECTIVES: Radiography remains the mainstay of diagnostic and follow-up imaging. In view of the risks and the increasing use of ionizing radiation, dose reduction is a key issue for research and development. The introduction of digital radiography and the associated access to image postprocessing have opened up new opportunities to minimize the radiation dosage. These advances are contingent upon quality controls to ensure adequate image detail and maintenance of diagnostic confidence. The purpose of this study was to investigate the clinical applicability of postprocessed low-dose images in skeletal radiography. METHODS: In our study setting, the median radiation dose for full dose X-rays was 9.61 dGy*cm2 for pelvis, 1.20 dGy*cm2 for shoulder and 18.64 dGy*cm2 for lumbar spine exams. Based on these values, we obtained 200 radiographs for each anatomic region in four consecutive steps, gradually reducing the dose to 84%, 71%, 60% and 50% of the baseline using an automatic exposure control (AEC). 549 patients were enrolled for a total of 600 images. All X-rays were postprocessed with a spatial noise reduction algorithm. Two radiologists assessed the diagnostic value of the radiographs by rating the visualization of anatomical landmarks and image elements on a five-point Likert scale. A mean-sum score was calculated by averaging the two reader's total scores. Given the non-parametric distribution, we used the Mann-Whitney U test to evaluate the scores. RESULTS: Median dosage at full dose accounted for 38.4%, 48 and 53.2% of the German reference dose area product for shoulder, pelvis and lumbar spine, respectively. The applied radiation was incrementally reduced to 21.5%, 18.4% and 18.7% of the respective reference value for shoulder, pelvis and lumbar spine. Throughout the study, we observed an estimable tendency of superior quality at higher dosage in overall image quality. Statistically significant differences in image quality were restricted to the 50% dose groups in shoulder and lumbar spine images. Regardless of the applied dosage, 598 out of 600 images were of sufficient diagnostic value. CONCLUSION: In digital radiography image postprocessing allows for extensive reduction of radiation dosage. Despite a trend of superior image detail at higher dose levels, overall quality and, more importantly, diagnostic utility of low-dose images was not significantly affected. Therefore, our results not only confirm the clinical utility of postprocessed low-dose radiographs, but also suggest a widespread deployment of this advanced technology to ensure further dose limitations in clinical practice. ADVANCES IN KNOWLEDGE: The diagnostic image quality of postprocessed skeletal radiographs is not significantly impaired even after extensive dose reduction by up to 20% of the reference value.

Comparison of three freeware software packages for 18F-FDG PET texture feature calculation.

PURPOSE: To compare texture feature estimates obtained from 18F-FDG-PET images using three different software packages. METHODS: PET images from 15 patients with head and neck cancer were processed with three different freeware software: CGITA, LIFEx, and Metavol. For each lesion, 38 texture features were extracted from each software package. To evaluate the statistical agreement among the features across packages a non-parametric Kruskal-Wallis test was used. Differences in the features between each couple of software were assessed using a subsequent Dunn test. Correlation between texture features was evaluated via the Spearman coefficient. RESULTS: Twenty-three of 38 features showed a significant agreement across the three software (P < 0.05). The agreement was better between LIFEx vs. Metavol (36 of 38) and worse between CGITA and Metavol (24 of 38), and CGITA vs. LIFEx (23 of 38). All features resulted correlated (ρ > = 0.70, P < 0.001) in comparing LIFEx vs. Metavol. Seven of 38 features were found not in agreement and slightly or not correlated (ρ < 0.70, P < 0.001) in comparing CGITA vs. LIFEx, and CGITA vs. Metavol. CONCLUSION: Some texture discrepancies across software packages exist. Our findings reinforce the need to continue the standardization process, and to succeed in building a reference dataset to be used for comparisons.

Development of Quality-Controlled Low-Dose Protocols for Radiography in the Neonatal ICU Using a New Mobile Digital Radiography System.

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.

A comparison of manually populated radiology information system digital radiographic data with electronic dose management systems.

OBJECTIVE: To assess the accuracy and agreement of radiology information system (RIS) kerma-area product (KAP) data with respect to automatically populated dose management system (DMS) data for digital radiography (DR). METHODS: All adult radiographic examinations over 12 months were exported from the RIS and DMS at three centres. Examinations were matched by unique identifier fields, and grouped by examination type. Each centre's RIS sample completeness was calculated, as was the percentage of the RIS examination KAP values within 5% of their DMS counterparts (used as an accuracy metric). For each centre, the percentage agreement between the RIS and DMS examination median KAP values was computed using a Bland-Altman analysis. At two centres, up to 42.5% of the RIS KAP units entries were blank or invalid; corrections were attempted to improve data quality in these cases. RESULTS: Statistically significant intersite variation was seen in RIS data accuracy and the agreement between the uncorrected RIS and DMS median KAP data, with a Bland-Altman bias of up to 11.1% (with a -31.7% to 53.9% 95% confidence interval) at one centre. Attempts to correct invalid KAP units increased accuracy but produced worse agreement at one centre, a slight improvement at another and no significant change in the third. CONCLUSION: The RIS data poorly represented the DMS data. ADVANCES IN KNOWLEDGE: RIS KAP data are a poor surrogate for DMS data in DR. RIS data should only be used in patient dose surveys with an understanding of its limitations and potential inaccuracies.

Image Distortion in Biplanar Slot Scanning: Patient-specific Factors.

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.

Learning deformable registration of medical images with anatomical constraints.

Deformable image registration is a fundamental problem in the field of medical image analysis. During the last years, we have witnessed the advent of deep learning-based image registration methods which achieve state-of-the-art performance, and drastically reduce the required computational time. However, little work has been done regarding how can we encourage our models to produce not only accurate, but also anatomically plausible results, which is still an open question in the field. In this work, we argue that incorporating anatomical priors in the form of global constraints into the learning process of these models, will further improve their performance and boost the realism of the warped images after registration. We learn global non-linear representations of image anatomy using segmentation masks, and employ them to constraint the registration process. The proposed AC-RegNet architecture is evaluated in the context of chest X-ray image registration using three different datasets, where the high anatomical variability makes the task extremely challenging. Our experiments show that the proposed anatomically constrained registration model produces more realistic and accurate results than state-of-the-art methods, demonstrating the potential of this approach.

Evaluation and verification of a simplified lead equivalency measurement method.

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.

Increasing the precision in the estimates of noise power spectrum in digital x-ray imaging systems.

The noise power spectrum (NPS) of a digital x-ray imaging device is usually estimated from the average of periodograms of ROIs in images obtained with uniform radiation fields. The purpose of this work was developing a new estimator for calculating the NPS and comparing its uncertainties with those of the smoothed periodogram. The new estimator is built by removing those addends in the summation of the periodogram that do not contain information on stochastic noise. This was carried out by applying a short-length lag window to the autocorrelation function of noise. The length of the window was obtained from the support of this function. It has to be large enough not to eliminate information on noise autocorrelation and it has be as short as possible to minimize uncertainty. In this work, this length was set to three times the support of the autocorrelation function of noise. The new truncated sum (TS) estimator is shown to be unbiased and to have a much higher precision than that of the periodogram. The combined process of applying lag windows to the autocorrelation function of noise and removing addends with null expected values from the periodogram summation has a double effect on NPS curves. On the one hand, the curves are smoothed and, on the other hand, the uncertainties in the calculated values are highly reduced.

Image quality to estimate ventricular ejection fraction by last year medical students improves after short courses of training.

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.

An audit of the polytrauma fracture detection rate of clinicians evaluating lodox statscan bodygrams in two South African public sector trauma units.

BACKGROUND: Increasing global demand for specialized radiological investigations has resulted in delayed or non-reporting of plain trauma radiographs by radiologists. This is particularly true in resource-limited environments, where referring clinicians rely largely on their own radiographic interpretation. A wide accuracy range has been documented for non-radiologist reporting of conventional trauma radiographs. The Lodox Statscan whole-body digital X-ray machine is a relatively new technology that poses unique interpretive challenges. The fracture detection rate of trauma clinicians utilizing this modality has not been determined. OBJECTIVE: An audit of the polytrauma fracture detection rate of clinicians evaluating Lodox Statscan bodygrams in two South African public-sector Trauma Units. METHODS: A retrospective descriptive study of imaging data of Cape Town Level 1-equivalent public-sector Trauma Units during March-April 2015. Statscan bodygrams acquired for adult polytrauma triage were reviewed and correlated with follow-up imaging and patient records. Missed fractures were stratified by body part, mechanism of injury and ventilatory support. The fracture detection rate was determined with 95% confidence. The Generalised Fischer Exact Test assessed any association between the fracture site and failure of detection. Specialist orthopaedic review assessed the potential need for surgical management of missed fractures. RESULTS: 227 patients (male = 193, 85%; mean age: 33 years) were included; 195 fractures were demonstrated on the whole-body triage projections. Lower limb fractures predominated (n = 66, 34%). The fracture detection rate was 89% (95% CI = 86-93%), with the site of fracture associated with failure of detection (p = 0.01). Twelve of 21 undetected fractures (57%) involved the elbow or shoulder girdle. All elbow fractures (n = 3, 100%), more than half the shoulder girdle fractures (9/13,69%) and 12% (15/123) of extremity fractures were undetected. One missed fracture (1/21,4.7%) unequivocally required surgical management, while a further 7 (7/21, 33.3%) could potentially have benefitted from surgery, depending on follow-up imaging findings. CONCLUSION: This is the first analysis of the accuracy of bodygram polytrauma fracture detection by clinicians. Particular review of the shoulder girdle, elbow and extremities for subtle fractures, in addition to standardized limb positioning, are recommended for improved diagnostic accuracy in this setting. These findings can inform clinician training courses in this domain.

[Digital Breast Tomosynthesis Mammography System Registration Application Data Technical Review Concerns].

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.

Cascaded systems analysis of anatomic noise in digital mammography and dual-energy digital mammography.

In x-ray based imaging of the breast, contrast between fibroglandular (Fg) tissue and adipose (Ad) tissue is a source of anatomic noise. The goal of this work was to validate by simulation and experiment a mathematical framework for modelling the Fg component of anatomic noise in digital mammograpy (DM) and dual-energy (DE) DM. Our mathematical framework unifies and generalizes existing approaches. We compared mathematical predictions directly with empirical measurements of the anatomic noise power spectrum of the CIRS BR3D structured breast phantom using two clinical mammography systems and four beam qualities. Our simulation and experimental results showed agreement with mathematical predictions. As a demonstration of utility, we used our mathematical framework in a theoretical spectral optimization of DM for the task of detecting breast masses. Our theoretical optimization showed that the optimal tube voltage for DM may be higher than that based on predictions that do not account for anatomic noise, in agreement with recent theoretical findings. Additionally, our theoretical optimization predicts that filtering tungsten-anode x-ray spectra with rhodium has little influence on lesion detectability, in contrast with previous findings. The mathematical methods validated in this work can be incorporated easily into cascaded systems analysis of breast imaging systems and will be useful when optimizating novel techniques for x-ray-based imaging of the breast.

Comparison of image quality of abdominopelvic CT in paediatric patients: low osmolar contrast media versus less iodine-containing iso-osmolar contrast media at different peak kilovoltages.

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.

Mammography Dose Survey Using International Quality Standards.

Digital mammography is the current standard for breast cancer screening. The absence of any dosimetric data, the quality standards, and the fear of radiation detriment, sometimes, hampers the smooth introduction of this technology and the launch of breast cancer screening programmes. As the breast cancer screening programmes are in development in Morocco, quality standards have been set in this study, so that any new breast cancer screening service could get started with their first analysis. The purpose of this study was to report the first Moroccan breast dose and to test quality standards compared with European guidelines. A dosimetric study is conducted by calculating mean glandular dose (MGD) for patients' breasts and polymethyl methacrylate (PMMA) for each thickness from recorded radiographic factors and X-ray tube (output and half-value layer) measurements using Dance's model for a digital mammography system. This is carried out to determine the correlation between phantom and patient measurements. The mean MGD for patient data was 1.02 ± 0.5 mGy and the compressed breast thickness was 55 ± 14 mm. For compressed breast thickness range of 50-60 mm, the MGD was 0.94 ± 0.3 mGy and the dose calculated with PMMA phantom for the same range thickness was 1.33 mGy. The results of MGD as a function of PMMA thickness is lower than the achievable limit curve proposed in the European guidelines. The average doses, which depend on the technical parameters of the mammography equipment, are in line with values obtained in European guidelines. In addition, an investigation is needed throughout the Moroccan territory, in the sense of optimization of radiological practices and techniques in mammographic centres aligning with the international recommendations.

Evaluating the use of exposure indicators in digital x-ray imaging system: Gauteng South Africa.

INTRODUCTION: Exposure indicators (EIs) are the only indicator of correct exposure technique in digital x-ray imaging systems but the use of such indicators remains largely unexplored in a South African setting. With exposure creep in the digital radiography age being a worldwide phenomenon, the study investigated radiographers' familiarity and use of EIs, providing insight into current exposure technique practices in this setting. METHODS: An explorative and descriptive quantitative study was conducted at 10 randomly selected radiography clinical training facilities in Gauteng, South Africa. The study used a questionnaire consisting of 26 questions based on familiarity with and use of EIs and radiographers' attitude to ionising radiation. RESULTS: A response of rate of 49.3% was achieved. Results show a low number of respondents (54.3%) had a perfectly correct understanding of the exposure indicator (EI) and only 55.7% of respondents made correct use of the EI. CONCLUSION: Observable lack of familiarity and use of the EI suggests that improvements could be made to the training radiographers receive on digital imaging systems. Moreover radiographers need to be vigilant against making decisions in digital radiography using knowledge that may relate exclusively to analogue radiography.

The Use of Digital Side Markers (DSMs) and Cropping in Digital Radiography.

INTRODUCTION: This article explores two phenomena in the general radiography environment-the increasing use of digital side markers (DSMs) by radiographers and the possibility for radiographers to "crop" radiographs post-exposure. This article offers originality by identifying the rationales of radiographers when using digital equipment. METHODS: This study formed part of a larger ethnographic study undertaken in the United Kingdom (UK). Participant observation and semi-structured interviews were used. Overt participant observation identified cropping and DSM placement within the X-ray room. Semi-structured interviews later supported and/or refuted the rationale for DSMs and cropping clinically. RESULTS: Two themes are discussed. First, radiographers support the use of DSMs by suggesting that mistakes will happen regardless of using an ASM and/or DSM. Furthermore, it is proposed that ASMs and DSMs can be interchangeably used in practice. Second, radiographers acknowledge the use of cropping ensuring their radiographs resemble "a textbook image." This leads to question the optimum use of collimation in the clinical environment and how it may go unnoticed. CONCLUSION: This article concludes by recognizing some challenges digital radiography currently provides. The rationale and continuing use of DSMs and cropping of radiographs by radiographers highlights alternate complexities with digital technology in the clinical environment and how we may best overcome such challenges that influence the profession.

Quantitative analysis of effects of the grid specifications on the quality of digital radiography images.

A grid is one of the key components of a digital radiography (DR) system because it removes scattered radiation, which arises when X-rays penetrate an object and improves diagnostic accuracy by enhancing image quality. With the widespread use of DR systems, demand for grids with high precision has simultaneously increased. Because unsuitable grids may decrease image quality and lead to misdiagnosis, using optimised grids for DR systems is critical. In this study, we aimed to analyse the quality of X-ray images acquired using grids with different specifications and proposed standardised criteria for grid use on the basis of our results. We measured modulation transfer function (MTF), normalised noise power spectrum (NNPS) and detective quantum efficiency (DQE) using grids with different ratios (10:1, 12:1 and 15:1) with or without implementing poly methyl methacrylate (PMMA) phantoms (0-20 cm). Pixel pitch of the detector used in this experiment was 143 µm. Based on this, a grid with a line frequency of 85 line pairs/cm was selected to prevent distortion caused by implementing unoptimised grids. As a result, the NNPS was found to increase when using the grid, and the difference in MTF and DQE was only measured when the scattered X-ray was generated by stacking the PMMA phantom. However, grids showed a positive effect MTF and DQE when the PMMA phantom was implemented. Specifically, MTF and DQE improved with increase in grid ratio. Thus, it is desirable to use a high-ratio grid to improve image quality.

Development and Evaluation of a Novel Point-of-Use Quality Assurance Tool for Digital Pathology.

CONTEXT.­: Flexible working at diverse or remote sites is a major advantage when reporting using digital pathology, but currently there is no method to validate the clinical diagnostic setting within digital microscopy. OBJECTIVE.­: To develop a preliminary Point-of-Use Quality Assurance (POUQA) tool designed specifically to validate the diagnostic setting for digital microscopy. DESIGN.­: We based the POUQA tool on the red, green, and blue (RGB) values of hematoxylin-eosin. The tool used 144 hematoxylin-eosin-colored, 5×5-cm patches with a superimposed random letter with subtly lighter RGB values from the background color, with differing levels of difficulty. We performed an initial evaluation across 3 phases within 2 pathology departments: 1 in the United Kingdom and 1 in Sweden. RESULTS.­: In total, 53 experiments were conducted across all phases resulting in 7632 test images viewed in all. Results indicated that the display, the user's visual system, and the environment each independently impacted performance. Performance was improved with reduction in natural light and through use of medical-grade displays. CONCLUSIONS.­: The use of a POUQA tool for digital microscopy is essential to afford flexible working while ensuring patient safety. The color-contrast test provides a standardized method of comparing diagnostic settings for digital microscopy. With further planned development, the color-contrast test may be used to create a "Verified Login" for diagnostic setting validation.