The SENIEUR protocol and the efficacy of hepatitis B vaccination in healthy elderly persons by age, gender, and vaccine route.

BACKGROUND: Reduced response to hepatitis B vaccines is associated with aging, confounding and comorbid conditions, as well as inadvertent subcutaneous (SC) inoculation. We hypothesized that the antibody and T cell-mediated immune responses (T-CMI) of elderly adults to a vaccine intended for intramuscular (IM) administration would be attenuated when deposited into SC fat, independent of confounding conditions. RESULTS: Fifty-two healthy, community dwelling elderly adults (65-82 years), seronegative for HBV, were enrolled in the SENIEUR protocol as a strictly healthy population. These seniors were randomized to receive a licensed alum-adjuvanted recombinant HBV vaccine either SC or IM, with the inoculum site verified by imaging. The response rates, defined as hepatitis B surface antibodies (HBsAb) ≥10 IU/L, were significantly lower in the elderly than in young adults, a group of 12, healthy, 21-34-year-old volunteers. Moreover, elderly participants who received the vaccine IM were significantly more likely to be responders than those immunized SC (54% versus 16%, p = 0.008). The low seroconversion rate in the IM group progressively declined with increasing age, and responders had significantly lower HBsAb titers and limited isotype responses. Moreover, T-CMI (proliferation and cytokine production) were significantly reduced in both percentage of responders and intensity of the response for both Th1 and Th2 subsets in the elderly. CONCLUSIONS: Our data demonstrate the blunted immunogenicity of SC inoculation as measured by peak titers and response rates. Further, the qualitative and quantitative deficits in B- and T-CMI responses to primary alum adjuvanted protein antigens persisted even in strictly healthy elderly populations with verified IM placement compared to younger populations. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT04162223. Registered 14 November 2019. Retrospectively registered.

Implications of surface-rendered facial CT images in patient privacy.

OBJECTIVE: Three-dimensional and multiplanar reconstruction of CT images has become routine in diagnostic imaging. The technology also facilitates surface reconstruction, in which facial features and, as a result, patient identity may be recognized, leading to risk of violations of patient privacy rights. The purpose of this study was to assess whether volunteer viewers can recognize faces on 3D reconstructed images as specific patients. SUBJECTS AND METHODS: A total of 328 participants were included: 29 patients underwent clinically indicated CT of the maxillofacial sinuses or cerebral vasculature and were also photographed (group A); 150 patients volunteered to have their faces photographed (group B); and 149 observers reviewed the images. Surface-reconstructed 3D images of group A were generated from CT data, and digital photographs of both groups A and B were acquired for a total of 179 facial photographs. Image reviewers were recruited with a web-based questionnaire that required observers to match surface-reconstructed images generated from CT data with randomized digital photographs from among the 179 photographs. Data analyses were performed to determine the ability of observers to successfully match surface-reconstructed images with facial photographs. RESULTS: The overall accuracy among the image observers was approximately 61%. No significant differences were found with regard to sex, age, or ethnicity and accuracy of image observers. CONCLUSION: Image reviewers were relatively poor at even side-by-side matching of patient photographs with 3D surface-reconstructed images. This finding suggests that successful identification of patients using surface-rendered faces may be a relatively difficult task for observers.

Utilization of an ultra-low-field, portable magnetic resonance imaging for brain tumor assessment in lower middle-income countries.

Background: Access to neuroimaging is limited in low-middle-income countries (LMICs) due to financial and resource constraints. A new, ultra-low-field, low-cost, and portable magnetic resonance imaging (pMRI) device could potentially increase access to imaging in LMICs. Case Description: We have presented the first brain tumor case scanned using an Ultra-low-field pMRI at Aga Khan University Hospital in Karachi, Pakistan. Conclusion: The imaging results suggest that the pMRI device can aid in neuroradiological diagnosis in resource-constrained settings. Further, research is needed to assess its compatibility for imaging other neurological disorders and compare its results with conventional MRI results.

The Retail Outlet Health Kiosk Hypertension Trial (ROKHYT): Pilot Results.

BACKGROUND: Blood pressure (BP) control was only 43.7% in the National Health and Nutrition Survey (NHANES) survey in 2017-2018. Scalable, nonclinic-based strategies to control BP are needed. We therefore conducted a pilot trial of a text-messaging intervention in a national network of retail outlet health kiosks with BP devices. All study procedures were conducted remotely. METHODS: Eligible individuals (N = 140), based on average BP greater than or equal to 140/90 mm Hg at kiosks during the prior year, were randomized to intervention vs. usual care. Intervention consisted of tailored text messages providing educational information with embedded links to educational videos on topics related to BP control. BP measurements were obtained at kiosks at 3, 6, and 12 months following randomization; control was defined as BP < 140/90 mm Hg. Follow-up at 12 months was curtailed due to SARS-CoV-2. We therefore combined 12-month (N = 62) or carried forward 6-month (N = 61) data as the primary end point. RESULTS: Participants were 51.4% male, 70.7% white/Caucasian, had mean age of 52.1 years, and mean baseline BP 145.5/91.8 mm Hg. At the end point, 37.7% intervention vs. 27.4% usual care subjects achieved BP control (difference, 10.3%, 95% confidence interval -6.2%, 26.8%). In an intention-to-treat analysis with multiple imputation of missing data, 12-month BP control was 29.0% vs. 19.8% favoring intervention (difference, 9.2%. 95% confidence interval -7.3%, 25.7%); intervention vs. control differences in adjusted mean BP levels were systolic BP: -5.4 mm Hg (95% confidence interval: -13.5, 2.7) and diastolic BP: +0.6 mm Hg (95% confidence interval: -4.2, 5.4). CONCLUSIONS: These pilot results support the potential for a highly scalable text-messaging intervention to improve BP. CLINICAL TRIALS REGISTRATION: Trial Number NCT03515681.

The relative effect of vendor variability in CT perfusion results: a method comparison study.

OBJECTIVE: There are known interoperator, intraoperator, and intervendor software differences that can influence the reproducibility of quantitative CT perfusion values. The purpose of this study was to determine the relative impact of operator and software differences in CT perfusion variability. MATERIALS AND METHODS: CT perfusion imaging data were selected for 11 patients evaluated for suspected ischemic stroke. Three radiologists each independently postprocessed the source data twice, using four different vendor software applications. Results for cerebral blood volume (CBV), cerebral blood flow (CBF), and mean transit time (MTT) were recorded for the lentiform nuclei in both hemispheres. Repeated variables multivariate analysis of variance was used to assess differences in the means of CBV, CBF, and MTT. Bland-Altman analysis was used to assess agreement between pairs of vendors, readers, and read times. RESULTS: Choice of vendor software, but not interoperator or intraoperator disagreement, was associated with significant variability (p < 0.001) in CBV, CBF, and MTT. The mean difference in CT perfusion values was greater for pairs of vendors than for pairs of operators. CONCLUSION: Different vendor software applications do not generate quantitative perfusion results equivalently. Intervendor difference is, by far, the largest cause of variability in perfusion results relative to interoperator and intraoperator difference. Caution should be exercised when interpreting quantitative CT perfusion results because these values may vary considerably depending on the postprocessing software.

Ontology-assisted analysis of Web queries to determine the knowledge radiologists seek.

Radiologists frequently search the Web to find information they need to improve their practice, and knowing the types of information they seek could be useful for evaluating Web resources. Our goal was to develop an automated method to categorize unstructured user queries using a controlled terminology and to infer the type of information users seek. We obtained the query logs from two commonly used Web resources for radiology. We created a computer algorithm to associate RadLex-controlled vocabulary terms with the user queries. Using the RadLex hierarchy, we determined the high-level category associated with each RadLex term to infer the type of information users were seeking. To test the hypothesis that the term category assignments to user queries are non-random, we compared the distributions of the term categories in RadLex with those in user queries using the chi square test. Of the 29,669 unique search terms found in user queries, 15,445 (52%) could be mapped to one or more RadLex terms by our algorithm. Each query contained an average of one to two RadLex terms, and the dominant categories of RadLex terms in user queries were diseases and anatomy. While the same types of RadLex terms were predominant in both RadLex itself and user queries, the distribution of types of terms in user queries and RadLex were significantly different (p < 0.0001). We conclude that RadLex can enable processing and categorization of user queries of Web resources and enable understanding the types of information users seek from radiology knowledge resources on the Web.

Effect of ambient sound masking on the accuracy of computerized speech recognition.

PURPOSE: To evaluate the direct effect that sound masking has on computerized speech recognition (SR) accuracy in the digital reading room while eliminating the Lombard effect. MATERIALS AND METHODS: This study complies with HIPAA requirements, and the institutional review board determined that approval was not required; informed consent was obtained. Ten radiologists digitally recorded 20 selected reports. Recorded reports were transcribed by using a commercial SR system at sound-masking levels 1-4, representing lowest to highest A-weighted sound pressure measurements in decibels. Dictated reports were compared with original reports to determine numbers of errors. A repeated-measures analysis of variance was used for overall comparison of mean percentage of transcription inaccuracies across sound-masking levels, and paired t tests were used to compare each sound-masking level to the baseline. RESULTS: Mean percentage of transcription inaccuracies at baseline was 11.6% (range, 6.3%-26.1%). Mean percentages of transcription inaccuracies at sound-masking levels 1-4 were 11.3%, 12.3%, 13.0%, and 13.6%, respectively. Mean percentages of transcription inaccuracies differed across all sound-masking levels (P < .001) but not between baseline and sound-masking level 1 (P = .313). Mean percentages of transcription inaccuracies at sound-masking levels 2-4 were each significantly higher than at baseline (P < .01 for each). CONCLUSION: Low-level sound masking provided slightly but not significantly improved SR accuracy, whereas higher levels decreased transcription accuracy. Appropriate levels of sound masking in reading room environments may decrease the negative effect of ambient noise without a deleterious effect on SR accuracy.

Vision and quality in the digital imaging environment: how much does the visual acuity of radiologists vary at an intermediate distance?

OBJECTIVE: The purpose of this study was to examine the intermediate-distance visual acuity of a cross section of radiologists and to identify variation in visual acuity during a typical workday. SUBJECTS AND METHODS: Forty-eight radiologists completed a brief survey before undergoing visual acuity testing, with corrective lenses if routinely used, at three times of the day. Testing was performed with modified versions of a U.S. Federal Aviation Administration visual acuity test instrument. RESULTS: The mean acuity of radiologists across all measurements was 20/15 (logarithm of the minimum angle of resolution [logMAR], -0.109 +/- 0.105 [SD]). Visual acuity ranged from 20/30 to 20/10 (logMAR, 0.176 to -0.301). Mean visual acuity in the morning session was approximately 20/16 (logMAR, -0.0856). This value was statistically significantly lower than the mean visual acuity in both the early afternoon (logMAR, -0.124; p = 0.003) and the late afternoon (logMAR, -0.118; p = 0.015), both of which were approximately 20/15. This change was within the expected test-retest variability of Snellen acuity measurements. CONCLUSION: Although a statistically significant difference was detected between the visual acuity of radiologists in the morning and acuity in other parts of the day, this difference was relatively modest and within previously published ranges of variability for similar visual acuity tests. It is unlikely that such variation in visual acuity among radiologists influences diagnostic performance. Not every radiologist had 20/20 vision, a few needed visual correction, and more than a few had not undergone a thorough eye examination for as many as 15 years before the study.

Informatics in radiology: IHE teaching file and clinical trial export integration profile: functional examples.

The digital revolution in radiology introduced the need for electronic export of medical images. However, the current export process is complicated and time consuming. In response to this continued difficulty, the Integrating the Healthcare Enterprise (IHE) initiative published the Teaching File and Clinical Trial Export (TCE) integration profile. The IHE TCE profile describes a method for using existing standards to simplify the export of key medical images for education, research, and publication. This article reviews the authors' experience in implementing the TCE profile in the following three processes: (a) the retrieval of images for a typical teaching file application within a TCE-compliant picture archiving and communication system (PACS); (b) the export of images, independent of TCE compliance of the PACS, to a typical teaching file application; and (c) the TCE-compliant transfer of images for publication. These examples demonstrate methods with which the TCE profile can be implemented to ease the burden of collecting key medical images from the PACS.

Informatics in radiology: GridCAD: grid-based computer-aided detection system.

Grid computing-the use of a distributed network of electronic resources to cooperatively perform subsets of computationally intensive tasks-may help improve the speed and accuracy of radiologic image interpretation by enabling collaborative computer-based and human readings. GridCAD, a software application developed by using the National Cancer Institute Cancer Biomedical Informatics Grid architecture, implements the fundamental elements of grid computing and demonstrates the potential benefits of grid technology for medical imaging. It allows users to query local and remote image databases, view images, and simultaneously run multiple computer-assisted detection (CAD) algorithms on the images selected. The prototype CAD systems that are incorporated in the software application are designed for the detection of lung nodules on thoracic computed tomographic images. GridCAD displays the original full-resolution images with an overlay of nodule candidates detected by the CAD algorithms, by human observers, or by a combination of both types of readers. With an underlying framework that is computer platform independent and scalable to the task, the software application can support local and long-distance collaboration in both research and clinical practice through the efficient, secure, and reliable sharing of resources for image data mining, analysis, and archiving.

Traumatic dissection of the internal carotid artery.

We present the case of an 11-year-old male who had a dissection of his left internal carotid artery following a rather innocuous mechanism of injury. Although this phenomenon is documented in the medical literature, it remains a relatively rare event following blunt injury to the head and neck (0.3% occurrence rate in 1 study spanning 7 years). (Despite its rarity, it remains an important cause of cerebrovascular accidents in children. 2) Children presenting with gross neurologic abnormalities following blunt trauma to the head or neck should be considered to have sustained injury to the carotid arteries until proven otherwise.

Detection of cervical spine fracture on computed radiography images a monitor resolution study.

RATIONALE AND OBJECTIVES: The purpose of this study was to evaluate the diagnostic accuracy of radiologists using monochrome medical-grade 5 megapixel (MP), 3 MP, 2 MP, and 1 MP displays for the detection of cervical fractures on cervical radiographs, while controlling factors such as luminance and ambient conditions. MATERIALS AND METHODS: Institutional review board approval was obtained. Two hundred lateral cervical computed radiography images, 97 with fractures, were randomly displayed on 5-MP, 3-MP, 2-MP, or 1-MP liquid crystal displays (LCDs) for a total of 450 interpretations per display. These radiographs were presented in eight sessions, each with 25 radiographs, to nine readers. The reference standard for all cases was computed tomography. Ambient lighting, monitor luminance, and gamma were controlled throughout the study. Measures included receiver operator characteristic areas under the curve (AUC), sensitivity, specificity, and accuracy, mean elapsed time by display, and mean confidence level by display. One way analysis of variance was performed. Results were considered to be significant at an alpha level of 0.05. RESULTS: AUCs were 0.76 (95% CI, 0.72-0.80) for the 1 MP, 0.80 (95% CI, 0.76-0.84) for the 2 MP, 0.77 (95% CI, 0.73-0.81) for the 3 MP, and 0.76 (95% CI, 0.72-0.80) for the 5 MP medical grade LCDs. There was no significant difference in the AUCs (P values between .0651 and .8693), confidence (P = .158), or interpretation times (P = .751). CONCLUSION: When controlling factors such as luminance and ambient light, a difference in accuracy in the detection of cervical fractures by resolution could not be detected when using medical-grade displays. Interpretation time and confidence were also not affected by resolution.

GridIMAGE: a novel use of grid computing to support interactive human and computer-assisted detection decision support.

This paper describes a Grid-aware image reviewing system (GridIMAGE) that allows practitioners to (a) select images from multiple geographically distributed digital imaging and communication in medicine (DICOM) servers, (b) send those images to a specified group of human readers and computer-assisted detection (CAD) algorithms, and (c) obtain and compare interpretations from human readers and CAD algorithms. The currently implemented system was developed using the National Cancer Institute caGrid infrastructure and is designed to support the identification of lung nodules on thoracic computed tomography. However, the infrastructure is general and can support any type of distributed review. caGrid data and analytical services are used to link DICOM image databases and CAD systems and to interact with human readers. Moreover, the service-oriented and distributed structure of the GridIMAGE framework enables a flexible system, which can be deployed in an institution (linking multiple DICOM servers and CAD algorithms) and in a Grid environment (linking the resources of collaborating research groups). GridIMAGE provides a framework that allows practitioners to obtain interpretations from one or more human readers or CAD algorithms. It also provides a mechanism to allow cooperative imaging groups to systematically perform image interpretation tasks associated with research protocols.

Radiologist assessment of PACS user interface devices.

INTRODUCTION: The process of radiologic interpretation has been revolutionized with the adoption of filmless imaging. Despite the radical change in viewing techniques and a rapidly expanding array of display, navigation, and manipulation tools, the keyboard-and-mouse configuration remains the standard for user interaction during radiologic interpretation. METHOD: In this study, 6 readers evaluated 6 alternative user interface devices (UIDs), including 5-button and 8-button mice, a gyroscopic mouse, a multimedia controller, a handheld mouse-and-keyboard combination device, and a gaming joystick. Each participant assessed each device during the real-time daily imaging interpretation of magnetic resonance, computed tomographic, and general x-ray studies over a 2-week period and completed a detailed questionnaire on the ease of use, comparative utility as an alternative device to mouse and QWERTY keyboard, efficiency, workflow, and the ease of customized programming. RESULTS: No single device was completely able to replace the mouse and keyboard in the estimation of participants, and the 5-button mouse was preferred over the 8-button mouse, although several participants noted that this might be a function of learning curves that exceeded the 2-week study period for each device. Several specific functionalities of the alternative UIDs were praised by users, who also suggested the possibility of combining these alternative devices for 2-handed use. CONCLUSION: Consideration should be given to the potential for the increased acceptance of and efficiency with alternative UIDs that can be integrated into picture archiving and communications system (PACS) workstations. Additional studies are planned to use software applications to evaluate different UIDs at PACS workstations.

Design and ergonomic considerations for the filmless environment.

Planning and executing the redesign of a traditional institutional radiology reading room to conform to the radically different requirements of digital imaging are reviewed, with examples drawn from the authors' experience and from the growing body of literature on this subject. Included are best-practice recommendations and real-life examples on initial design and planning, stakeholder involvement, identifying and hiring consultants, architectural planning, the designation of a radiology point person, rethinking room and workstation design, the selection of ergonomic furniture and fittings, identifying optimal environmental elements, fine tuning and lessons learned, and going digital.

Integrating imaging informatics into the radiology residency curriculum: rationale and example curriculum.

Imaging informatics, as part of the wider emerging discipline of medical informatics, remains poorly defined. However, many educators agree that formalized and flexible training in the collection, display, manipulation, storage, retrieval, and communication of imaging data, as well as the integration of these data into larger databases, should be introduced into the period of radiology residency training. The authors review the importance of such training to those individuals now preparing for clinical practice and research. They describe a sample imaging informatics curriculum that can be incorporated into a 4-year radiology residency program and the significance of such training in establishing a new subdiscipline focusing on imaging information technologies.

Multi-institutional analysis of computed and direct radiography: part II. Economic analysis.

PURPOSE: To compare economic aspects of equipment configurations, productivity levels, and patient waiting times in the performance of computed radiography (CR) and direct radiography (DR). MATERIALS AND METHODS: The study received internal review board exemption status, without the need for informed patient consent. Data from four study sites were used to calculate the CR-DR crossover point (defined as the point at which the cost-effectiveness of DR equals that of CR) and CR-DR annual cost differentials. Analyzed variables included equipment and operating costs, examination volumes, and productivity. A program was developed to simulate patient arrival times, number of patient examinations, and patient waiting times on the basis of average annualized parameters for each of the four clinics. Sensitivity analyses were conducted to assess utilization rates and determine cost optimization. Utilization rates were compared with the number of excess long-stay CR patients (ie, patients who spent more than 30 minutes waiting in the radiology department prior to CR examination) and with the cost (per excess long-stay CR patient who waited more than 60 minutes) averted by using DR. RESULTS: Excess annual costs for DR over CR at the four sites ranged from $50,757 to $75,303. At extrapolated levels of economic penalties for long waiting times, the crossover point at which the DR cost became justifiable was when CR capacity utilization rates approached or exceeded 80%. CONCLUSION: In the current practice environment, with capacity utilization rates well below 80%, CR is likely to be a more cost-effective technology for the majority of general radiography providers.

Multi-institutional analysis of computed and direct radiography: part I. Technologist productivity.

PURPOSE: To assess whether it is feasible to measure and compare work-flow times across institutional variations, and to apply such a comparison to technologist productivity in the performance of general radiographic examinations with computed radiography (CR) and direct radiography (DR). MATERIALS AND METHODS: The study received internal review board exemption. Participants were informed about the study and willingly participated. Observational time-motion analyses were performed at four sites at which CR and DR are used concurrently. The time taken by the technologist for patient preparation, positioning, exposure, and postacquisition processing, and for the examination as a whole, was recorded. Data collected reflect unique elements at each clinical center, and no standardized work flow was imposed. Work-flow performance times were correlated with each site profile. Preliminary statistical analyses included examination of distributions of original and combined variables. Descriptive statistics were presented as means or frequencies, depending on whether the data were continuous or categorical. Continuous variables were compared by using the Student t test. Timing differences between CR and DR for each clinical center were compared, and all data were analyzed by using commercially available statistical software. RESULTS: For all four study sites, statistically significant total examination time differences were observed when comparing CR and DR (P < .001). The single step in the examination that was found to be the largest contributor to time difference was postacquisition processing, which accounted for 30%-100% of the total time difference between the two technologies. The most time-efficient sites were those that had in-room postacquisition processing capability and fully functional integration with the radiology information system. Investigators at two study sites compared times for two-view chest radiography only, and those at the other two study sites compared times for multiview general radiographic examinations. Only the results of two-view comparisons were reported for each site. CONCLUSION: Overall technologist time was significantly shorter when performing tasks associated with DR than when performing comparable tasks associated with CR, a difference that appears to result largely from technology configuration, staffing, and patient management.

Nuclear cardiology patient tracking using a palm-based device: methods and clinician satisfaction.

Handheld personal computers are popular, easy to use, inexpensive, portable, and can share data among different operating systems. In our institution, nuclear cardiology testing is performed in the nuclear medicine department and jointly reported by radiologists and cardiologists. The objective of this article is to describe a system for recording nuclear cardiology data and to assess clinician satisfaction using handheld computers with the Palm Operating System. We devised a Palm-based relational database/ using commercially available software (HanDBase) that requires minimal computer expertise to implement and maintain. Data are collected by the cardiologist and synchronized to a single central relational database compatible with Microsoft Access. We assessed cardiologists' satisfaction with this system. Cardiologists unanimously agreed that this system had a positive impact on patient management and cardiology fellow education. They were satisfied with ease of data input, sharing, retrieval, and clarity of data display. The cardiologist with the least experience in using the software took longer to input data and thought that it prolonged the nuclear cardiology rounds. The idea to develop this software was to ease data entry using shortcuts and lists, limiting data stored to that essential for patient management and also to transmit data easily between staff. The cardiologist with the most experience in using the software felt more comfortable and satisfied with it. This was perhaps due to his continuous involvement in the development of this system. Like any new system, there is a learning curve in using this software. The software was easy to customize, and support and tutorials were found on the manufacturer's Web site. The system of collecting data using handheld computers with the Palm Operating System is easy to use, relatively inexpensive, accurate, and secure. The user-friendly system provides prompt, complete, and accurate data, enhancing the education of fellows while facilitating the job of cardiologists.

Ten filmless years and ten lessons: a 10th-anniversary retrospective from the Baltimore VA Medical Center.

The authors review a decade's experience in the nation's first filmless radiology department and outline the challenges and rewards of the transition. They summarize their experience with 10 cautionary and informative lessons on making the process more successful, more efficient, and less stressful. A number of possible avenues of new research and assessment on the effects of filmless operation on radiologists, imaging staff, referring clinicians, and patients are highlighted.