Radiological Physics Research Articles

Invited Commentary: From Unacceptable to Intolerable

Invited Commentary: From Unacceptable to Intolerable

How We Got Here: The Legacy of Anti-Black Discrimination in Radiology

Current disparities in the access to diagnostic imaging for Black patients and the underrepresentation of Black physicians in radiology, relative to their representation in the general U.S. population, reflect contemporary consequences of historical anti-Black discrimination. These disparities have existed within the field of radiology and professional medical organizations since their inception. Explicit and implicit racism against Black patients and physicians was institutional policy in the early 20th century when radiology was being developed as a clinical medical field. Early radiology organizations also embraced this structural discrimination, creating strong barriers to professional Black radiologist involvement. Nevertheless, there were numerous pioneering Black radiologists who advanced scholarship, patient care, and diversity within medicine and radiology during the early 20th century. This work remains important in the present day, as race-based health care disparities persist and continue to decrease the quality of radiology-delivered patient care. There are also structural barriers within radiology affecting workforce diversity that negatively impact marginalized groups. Multiple opportunities exist today for antiracism work to improve quality of care and to apply standards of social justice and health equity to the field of radiology. An initial step is to expand education on the disparities in access to imaging and health care among Black patients. Institutional interventions include implementing community-based outreach and applying antibias methodology in artificial intelligence algorithms, while systemic interventions include identifying national race-based quality measures and ensuring imaging guidelines properly address the unique cancer risks in the Black patient population. These approaches reflect some of the strategies that may mutually serve to address health care disparities in radiology. © RSNA, 2023 See the invited commentary by Scott in this issue. Quiz questions for this article are available in the supplemental material.

MFGAN: Multi-modal Feature-fusion for CT Metal Artifact Reduction Using GANs

Due to the existence of metallic implants in certain patients, the Computed Tomography (CT) images from these patients are often corrupted by undesirable metal artifacts, which causes severe problem of metal artifact. Although many methods have been proposed to reduce metal artifact, reduction is still challenging and inadequate. Some reduced results are suffering from symptom variance, second artifact, and poor subjective evaluation. To address these, we propose a novel method based on generative adversarial nets (GANs) to reduce metal artifacts. Specifically, we firstly encode interactive information (text) and imaging CT (image) to yield multi-modal feature-fusion representation, which overcomes representative ability limitation of single-modal CT images. The incorporation of interaction information constrains feature generation, which ensures symptom consistency between corrected and target CT. Then, we design an enhancement network to avoid second artifact and enhance edge as well as suppress noise. Besides, three radiology physicians are invited to evaluate the corrected CT image. Experiments show that our method gains significant improvement over other methods. Objectively, ours achieves an average increment of 7.44% PSNR and 6.12% SSIM on two medical image datasets. Subjectively, ours outperforms others in comparison in term of sharpness, resolution, invariance, and acceptability.

68Ga]Ga-FAPI-04 PET/CT on assessing Crohn's disease intestinal lesions.

Fibrosis and inflammation are major pathological changes of Crohn's disease (CD). Early detection and accurate severity evaluation of CD are critical for patient's prognosis. Endoscopy is widely used to evaluate CD progression. Herein, we evaluated the efficacy of [68Ga]Ga-FAPI-04 PET/CT to identify lesions and assess the progression of CD. All CD patients received computed tomography enterography (CTE), [68Ga]Ga-FAPI-04 PET/CT examination, and ileocolonoscopy within 1week. Two independent gastroenterologists computed the Crohn's disease activity index (CDAI) of all patients. Two radiology physicians assessed the CTE images separately, and the CTE scores were calculated. Lastly, two nuclear medicine physicians independently examined the [68Ga]Ga-FAPI-04 PET/CT images. Once the FAPI uptake of the intestinal segment was equal or higher relative to the liver (considered FAPI-positive), the target-to-background ratio (TBR) and global FAPI PET/CT score were computed, representing the independent intestinal activity and activity of all intestinal segments, respectively. Levels of fecal calprotectin (FCP) and C-reactive protein (CRP) were determined before the endoscopy. The Crohn's disease endoscopy index of severity (CDEIS) and the simple endoscopic score for Crohn's disease (SES-CD) were calculated during the endoscopy. Finally, all data were obtained and analyzed. There were 74 intestinal segments in 16 patients were assessed. [68Ga]Ga-FAPI-04 PET/CT identified 42 of 45 endoscopically lesioned segments (endoscopic lesions detection sensitivity: 93.3%), while CTE identified 39 of them (endoscopic lesions detection sensitivity: 86.7%). According to the receiver operating characteristic (ROC) analysis, [68Ga]Ga-FAPI-04 PET/CT showed better performance in the detection of endoscopic lesions compared with CTE (P < 0.05). The TBR was significantly associated with the CTE score (r = 0.81; (95% CI): 0.736-0.869; P < 0.0001) and SES-CD values (r = 0.86; (95% CI): 0.776-0.908; P < 0.0001). In addition, the global FAPI PET/CT score was significantly correlated with FCP (r = 0.52; 95% CI, 0.02-0.81; P = 0.039), CRP (r = 0.60; 95% CI, 0.13-0.85; P = 0.014), CDEIS (r = 0.55; 95% CI, 0.06-0.83; P = 0.028), and CDAI (r = 0.81; 95% CI, 0.50-0.93;P < 0.0001). In summary, [68Ga]Ga-FAPI-04 PET/CT correlated well with endoscopic, CTE, clinical, and biomarkers of CD. It was also highly sensitive in the detection of different classes of lesions in all intestinal segments, and unlike other examinations, this technique required no patient fasting or bowel preparation. Therefore, [68Ga]Ga-FAPI-04 PET/CT may be a promising method for assessing the activity of CD.

Recent Topics on Radiological Physics and Technology

Recent Topics on Radiological Physics and Technology

Assessment of a combined musculoskeletal and chest deep learning-based detection solution in an emergency setting

Rationale and objectivesTriage and diagnostic deep learning-based support solutions have started to take hold in everyday emergency radiology practice with the hope of alleviating workflows. Although previous works had proven that artificial intelligence (AI) may increase radiologist and/or emergency physician reading performances, they were restricted to finding, bodypart and/or age subgroups, without evaluating a routine emergency workflow composed of chest and musculoskeletal adult and pediatric cases. We aimed at evaluating a multiple musculoskeletal and chest radiographic findings deep learning-based commercial solution on an adult and pediatric emergency workflow, focusing on discrepancies between emergency and radiology physicians. Material and methodsThis retrospective, monocentric and observational study included 1772 patients who underwent an emergency radiograph between July and October 2020, excluding spine, skull and plain abdomen procedures. Emergency and radiology reports, obtained without AI as part of the clinical workflow, were collected and discordant cases were reviewed to obtain the radiology reference standard. Case-level AI outputs and emergency reports were compared to the reference standard. DeLong and Wald tests were used to compare ROC-AUC and Sensitivity/Specificity, respectively. ResultsResults showed an overall AI ROC-AUC of 0.954 with no difference across age or body part subgroups. Real-life emergency physicians’ sensitivity was 93.7 %, not significantly different to the AI model (P = 0.105), however in 172/1772 (9.7 %) cases misdiagnosed by emergency physicians. In this subset, AI accuracy was 90.1 %. ConclusionThis study highlighted that multiple findings AI solution for emergency radiographs is efficient and complementary to emergency physicians, and could help reduce misdiagnosis in the absence of immediate radiological expertize.

The Effect of Pre-Operative Verbal Confirmation for Interventional Radiology Physicians on Their Use of Personal Dosimeters and Personal Protective Equipment.

Interventional radiology (IR) physicians must be equipped with personal passive dosimeters and personal protective equipment (PPE); however, they are inconsistently used. Therefore, we aimed to explore practical measures to increase PPE usage and ascertain whether these measures could lead to an actual decrease in exposure doses to IR physicians. Dosimeters and PPE were visually inspected. Then, a pre-operative briefing was conducted as a direct intervention, and the use of dosimeters and PPE was verbally confirmed. Finally, the intervention effect was verified by measuring the use rates and individual exposure doses. Because of the intervention, the use rate markedly improved and was almost 100%. However, both the effective dose rate (effective dose/fluoroscopy time) and the lens equivalent dose rate (lens equivalent dose/fluoroscopy time) showed that the intervention led to a statistically significant increase in exposure (effective dose rate: p = 0.033; lens equivalent dose rate: p = 0.003). In conclusion, the proper use of dosimeters and PPE raised the radiation exposure values for IR physicians immediately after the intervention, which was hypothesized to be due to the inclusion of exposure overlooked to date and the changes in the dosimeter management method from a single- to a double-dosimeter approach.

Factors affecting patients’ waiting time at the Radiology Department

Aim of Study: To identify the extent and causes for prolonged patient waiting times and overcrowding at the Radiology Department (RD) in Aseer Central Hospital, Abha City, Saudi Arabia. Methods: A cross-sectional observational study design was followed. It included 107 staff members at the RD in Aseer Central Hospital. A data collection tool was designed by the researchers and used for data collection. Results: 51.4% of patients were referred to RD from the outpatient clinics, 27.3% were referred from the ED, while 21.3% were inpatients. Monday and Tuesday were the most overcrowded days at the RD (33.3% and 20.8%, respectively). Almost half of the patients (47%) stayed in the waiting area for 1-3 hours. Patient waiting times differed significantly according to their days of received radiologic services, with the longest waiting time being on Wednesday (44.4%, p=0.021), and according to patients provided radiologic services. The most frequently stated causes by the radiology staff for overcrowding at the RD were the “huge number of patients received directly from the community who did not go via a primary health care center”; “the large number of non-emergency patients” and the “socially recommended cases sent to RD via the ED” (45.8%, 32.7% and 29.9%, respectively). Conclusions: Patient waiting times are unduly prolonged. It is mostly 1-3 hours. The main bulk of overcrowding comes from patients referred from the outpatient clinics. The main causes for overcrowding are the excessive number of non-emergency, unscheduled patients, and the socially recommended cases, in addition to the shortage of specialist radiology physicians. Recommendations: There is a need to implement an elaborate system to organize unscheduled patients, who may crowd out other emergency patients and to allocate a special radiology section for patients referred from the ED. To increase the number of serving specialist radiologists at the RD of Aseer Central Hospital. To enforce provided radiology services at primary care centers in Aseer Region. Key Words: Waiting time, Radiology Department, Patient referrals

395 Is Lower Extremity Venography Necessary in Pulmonary Embolism CT Imaging?

Study Objective: Pulmonary thromboembolism (PTE) is the third most mortal disease after acute myocardial infarction and cerebrovascular events. Ten percent of patients with pulmonary embolism also have deep venous thrombosis (DVT). Point-of-care compression ultrasound (PoCUS) is performed in the emergency room to detect the DVT of the patients, and doppler ultrasonography is performed by the radiology physicians. In addition to pulmonary computerized tomography (CT) angiography, lower extremity venography is also performed.

Academic program recommendations for graduate degrees in medical physics: AAPM Report No. 365 (Revision of Report No. 197).

Academic program recommendations for graduate degrees in medical physics: AAPM Report No. 365 (Revision of Report No. 197).

Informed Consent in Dentomaxillofacial Radiology: A Cross- Sectional Study

Objective: This study assessed the opinions and attitudes of dentomaxillofacial (DMF) radiology physicians worldwide about informed consent in terms of oral radiology applications. &#x0D; Methods: DMF radiology physicians in various countries were invited to this study via e-mail. The participants answered their demographic information (gender, age, years of experience, title, institution, and country), and questions about informed consent. The Pearson chi-square and Fisher’s exact tests were used for statistical analysis &#x0D; Results: From 22 countries, 46 male (51.7%) and 43 female (48.3%) DMR radiology physicians completed the questionnaire. More than half of the participants (53.9%) were working in the university hospital, and the highest number of participants (32.6%) was from the European region. Most of the surveyors (70.8%) stated that consent is required in dental radiology. No statistically significant difference was found in the radiographic methods (intraoral, panoramic/extraoral, and cone-beam CT) applied in terms of obtaining consent (p &gt; 0.05). While middle-aged physicians (30 –45 age) thought that patients should not be informed about the risk of radiation causing cancer, experienced participants (45 age and above) stated that information should be given about the cancer risk (p &lt; 0.05). &#x0D; Conclusion: The results of this study showed that most of the DMF radiology physicians stated that they have responsibility for getting informed consent and only one-third of the participants inform patients about the risks of radiation.

Accuracy of Brain Computed Tomography Diagnosis by Emergency Medicine Physicians.

Objectives The objective of this study is to prospectively analyze emergency physicians' (EP's) abilities to interpret noncontrast computed tomography (NCCT) brain images in a blinded fashion and assess whether they can make medical decisions solely based on their interpretations. Methods A cross-sectional study was conducted at the emergency department (ED), King Saud University Medical City (KSU-MC), Saudi Arabia, over a period of one year, from May 2014 to May 2015. Any patient who underwent plain brain NCCT during the study period in our ED was included in this study. An independent attending neuroradiologist compared the EP's interpretations with the official final reports dictated by an on-call radiologist. Results A brain NCCT prospective chart audit of 1,524 patients was interpreted by ED physicians (EP) at KSU-MC from 2014–2015. The ages of patients were between 14 and 107 years, and the mean ± SD age was 45.6 ± 22.1 years. Radiological brain lesions were confirmed by EPs and radiology physicians in 230 (15.09) and 239 (15.68) patients, respectively, out of which concordance was observed in 170 (71.13) cases, with a kappa value of r = 0.675. Normal, chronic, and nil acute reports were made by EPs and radiology physicians for 1,295 (84.97) patients and 1,285 (84.32) patients, respectively, out of which concordance was observed in 1,225 (95.33) cases, with a kappa value of r = 0.672. The study results demonstrated that the overall agreement between EPs and radiologist specialists was 91.6, with a kappa value of .675 (p < 0.001). Conclusion Emergency physicians are moderately accurate at interpreting brain NCCT compared to radiologists. More research is needed to discover the most cost-effective technique for reducing the number of significant misinterpretations.

Availability of and factors related to interventional procedures for refractory pain in patients with cancer: a nationwide survey

BackgroundCancer pain may be refractory to standard pharmacological treatment. Interventional procedures are important for quality of analgesia. The aim of the present study was to clarify the availability of four interventional procedures (celiac plexus neurolysis/splanchnic nerve neurolysis, phenol saddle block, epidural analgesia, and intrathecal analgesia), the number of procedures performed by specialists, and their associated factors. In addition, we aimed to establish how familiar home hospice physicians and oncologists are with the different interventional procedures available to manage cancer pain.MethodsA cross-sectional survey using a self-administered questionnaire was conducted. Subjects were certified pain specialists, interventional radiologists, home hospice physicians, and clinical oncologists.ResultsThe numbers of valid responses/mails were 545/1,112 for pain specialists, 554/1,087 for interventional radiology specialists, 144/308 for home hospice physicians, and 412/800 for oncologists. Among pain specialists, depending on intervention, 40.9-75.2% indicated that they perform each procedure by themselves, and 47.5-79.8% had not performed any of the procedures in the past 3 years. Pain specialists had performed the four procedures 4,591 times in the past 3 years. Among interventional radiology specialists, 18.1% indicated that they conduct celiac plexus neurolysis/splanchnic nerve neurolysis by themselves. Interventional radiology specialists had performed celiac plexus neurolysis/splanchnic nerve neurolysis 202 times in the past 3 years. Multivariate analysis revealed that the number of patients seen for cancer pain and the perceived difficulty in gaining experience correlated with the implementation of procedures among pain specialists. Among home hospice physicians and oncologists, depending on intervention, 3.5-27.1% responded that they were unfamiliar with each procedure.ConclusionsAlthough pain specialists responded that the implementation of each intervention was possible, the actual number of the interventions used was limited. As interventional procedures are well known, it is important to take measures to ensure that pain specialists and interventional radiology physicians are sufficiently utilized to manage refractory cancer pain.

Workforce Diversity of Interventional Radiology Physicians in North America: Reflections on the U.S. Experience.

Achieving parity in representation within the field of Interventional Radiology (IR) across women and specific subsets of minority groups has been a challenge. The lack of a strongly diverse physician workforce in gender, race, and ethnicity suggests suboptimal recruitment after, during as well prior to IR training. There is a dearth of studies which effectively characterize the national demographic trends of the evolving IR workforce. This has prevented an accurate appraisal of continuing efforts to narrow the gaps in physician workforce diversity across the field of IR. To support these needs, this article illustrates historic trends while providing contemporary data that canvasses the status of diversity within the current IR physician and IR trainee workforce. It highlights the representation of those individuals historically underrepresented in medicine as well as women. It also highlights current obstacles to achieving equity, diversity, and inclusion within the field of IR as well as existing efforts that have been employed to mitigate this gap.

Diversity in Radiology: Current Status and Trends Over the Past Decade.

Background There have been growing efforts nationally and institutionally toward diversity in radiology. Purpose To analyze sex and racial and ethnic diversity over time (2010-2019) for the various levels of the U.S. academic radiology physician workforce in context of the available pipeline of medical students and trainees. Materials and Methods Data on sex and race and ethnicity were collected among medical school applicants, graduates, radiology residency applicants, residents, and different levels of academic radiology faculty. All trainee data were obtained from two time points, 2010-2011 and 2019-2020. Radiology faculty data were collected from 2010 to 2019. The sex and racial and ethnic composition at each academic level was compared between 2010 and 2019 using the χ2 test and a significance level of P < .05. Results In 2019, the percentage of female faculty among radiology instructors was 38% (251 of 655); assistant professors, 31% (1503 of 4801); associate professors, 28% (600 of 2161); professors, 22% (424 of 1901); and department chairs, 17% (37 of 220). The proportion of female faculty increased from 2010 to 2019, with the greatest relative increase in percentages among the more senior faculty positions. However, the proportion of female department chairs has only increased from 13% (27 of 203) in 2010 to 17% (37 of 220) in 2019. Across training levels, the most abrupt change in composition of female trainees occurred from medical school matriculates (52%, 11 160 of 21 614) to radiology residency applicants (29%, 656 of 2274), which largely stayed unchanged from 2010 to 2019. The proportion of Black or African American department chairs was 5% (10 of 220) in 2019, which was higher compared with that of assistant professor, associate professor, and professor levels for Black or African American faculty (3% [130 of 4949], 2% [41 of 2208], and 2% [35 of 1924], respectively), with proportions of Hispanic faculty at 5% (240 of 4949), 4% (96 of 2208), and 3% (60 of 1924), respectively. These proportions have not changed since 2010. Conclusion Identifying and addressing reasons for the low proportion of female radiology residency applicants despite a highly diverse pool of medical students would be key to increasing female representation in the field. The low representation of African American and Hispanic individuals in academic radiology is seen at all levels and has not changed much over time. Efforts to increase diversity may need to be focused toward the medical school and residency application levels. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Pandharipande and Shah in this issue.

A model for training ultrasound-guided fine-needle punctures.

SUMMARYOBJECTIVE:To evaluate the efficacy of a training program in ultrasound-guided fine needle puncture using a cost-effective model.METHODS:We evaluated the training of 20 resident radiology physicians, based on a theoretical course and a practical simulation part with models that focused on the puncture technique of thyroid nodules. The total time to perform the procedure, the number of punctures on the model surface, and the application of a questionnaire were used to assess the performance and confidence of the resident physicians in performing the procedure.RESULTS:The training model used was easy to reproduce, inexpensive, versatile, and capable of simulating the echotexture of thyroid tissue. There was a significant reduction in the total time needed to perform the procedure with a mean of 173.7 s±91.28 s from R1 and 112.8 s±17.66 s from R2 before the course vs. 19.2 s±112.8 s and 14.3 s±9.36 s, respectively, after the course (p<0.0001); as well as the number of superficial punctures, with a mean of 2.2 punctures±0.92 from R1 and 1.5 punctures±0.32 from R2 before the course vs 1.1 punctures±0.71 and 1.0 puncture±0.0, respectively, after the course (p<0.0001). There was also a subjective improvement in the performance and confidence in performing this procedure.CONCLUSIONS:An inexpensive and easy-to-reproduce gelatin-based model enabled adequate training of resident physicians and proved capable of improving their skills and confidence in simulating the procedure, even with a short period of training.

Development of Educational Media for Medical Trainees Studying MRI Physics: Effect of Media Format on Learning and Engagement.

MRI physics is a challenging subject for radiology residents and comprises a significant portion of the ABR CORE examination, which must be passed to achieve board certification. Despite established needs for increased quality and quantity of radiology physics resources, there is little information regarding the most effective method of engaging learners and delivering this content. To assess trainee perceptions of currently available MRI physics learning resources, a needs assessment survey was distributed to current members and recent graduates of our diagnostic radiology residency program. Based on the results of the needs assessment, we created three different types of media illustrating the fundamentals of MRI physics: text with images, text with animations, and a narrated video. Formal evaluation of the media via an institutional review board-approved, experimentally designed study helped us better understand the impact that media format had on deep structure learning, efficiency, and engagement. Respondents to the needs assessment indicated a desire for physics resources that were visually appealing with simplified details and associated practice questions. Participants demonstrated significant learning across all media formats but rated video as the most engaging media type. Knowledge of media attributes that positively impact trainee performance may inform content creators and educators alike when designing and distributing educational materials related to MRI physics.

Abstract No. 590 Augmented reality display in a hybrid OR: working toward improved ergonomics and performance for interventional radiologists

Interventional radiology (IR) physicians often face ergonomic challenges. Ideal positioning of imaging monitors and x-ray system controls in many IR and hybrid OR cases may not be possible due to physical obstruction from the c-arm and ancillary equipment. This study evaluates the clinical usability and effect on workflow of an augmented reality (AR) head mounted display (HMD) during IR procedures in a hybrid OR.

Commentary on “Outcomes of Stroke Thrombectomy Performed by Interventional Radiologists versus Neurointerventional Physicians”

The article “Outcomes of Stroke Thrombectomy Performed by Interventional Radiologists versus Neurointerventional Physicians” addresses an important and controversial issue of whether nonneuroscience interventional physicians should be performing stroke thrombectomy ( 1 Sacks D. Dhand S. Hegg R. et al. Outcomes of stroke thrombectomy performed by interventional radiologists versus neurointerventional physicians. J Vasc Interv Radiol. 2022; 33: 619-626 Google Scholar ). There is convincing evidence that stroke thrombectomy improves the clinical outcomes of large vessel occlusion (LVO) anterior circulation strokes and that it is cost effective ( 2 Powers W.J. Rabinstein A.A. Ackerson T. et al. Guidelines for the early management of patients with acute ischemic stroke: 2019 update to the 2018 guidelines for the early management of acute ischemic stroke: a guideline for healthcare professionals from the American Heart Association/American Stroke Association. Stroke. 2019; 50: e344-e418 Crossref PubMed Scopus (1847) Google Scholar , 3 Bulwa Z. Chen M. Stroke center designations, neurointerventionalist demand, and the finances of stroke thrombectomy in the United States. Neurology. 2021; 97: S17-S24 Crossref PubMed Scopus (2) Google Scholar ). This article provides data to support the position that interventional radiology (IR) physicians with additional training can achieve technical and clinical outcomes similar to those obtained by neurointerventional (NI) physicians. We do not take sides in this controversy. The purposes of this commentary are to appraise the current article critically, to examine its potential implications, and to provide an update on the issues of the supply of, demand for, and access to stroke thrombectomy. Outcomes of Stroke Thrombectomy Performed by Interventional Radiologists versus Neurointerventional PhysiciansJournal of Vascular and Interventional RadiologyVol. 33Issue 6PreviewTo test the hypothesis that interventional radiologists (IRs) and neurointerventional (NI) physicians have similar outcomes of endovascular stroke thrombectomy (EVT), which could be used to improve the availability of thrombectomy. Full-Text PDF

Assessment of the Body Posture of Interventional Radiologists.

Physicians in interventional radiology are exposed to high physical stress. To avoid negative long-term effects resulting from unergonomic working conditions, we demonstrated the feasibility of a system that gives feedback about unergonomic situations arising during the intervention based on the Azure Kinect camera. The overall feasibility of the approach could be shown.