294 research outputs found
Radiologist-patient consultation of imaging findings after neck ultrasonography:An opportunity to practice value-based radiology
Objective: To investigate how patients experience a radiologist-patient consultation of imaging findings directly after neck ultrasonography (US), and how much time this consumes. Materials and methods: This prospective randomized study included 109 consecutive patients who underwent neck US, of whom 44 had a radiologist-patient consultation of US results directly after the examination, and 65 who had not. Results: The median ratings of all healthcare quality metrics (friendliness of the radiologist, explanation of the radiologist, skill of the radiologist, radiologist's concern for comfort during the examination, radiologist's concern for patient questions/worries, overall rating of the examination, and likelihood of recommending the examination) were either good/high or very good/very high, without any significant differences between both patient groups. Patients who did not discuss the US results with the radiologist, were significantly more worried during the examination (P = 0.040) and had significantly higher anxiety levels after completion of the US examination (P = 0.027) than patients who discussed the US results with the radiologist. Fifty-one out of 55 responding patients (92.7%) indicated a radiologist-patient consultation of US results to be important. The median duration of US examinations that included a radiologist-patient consultation of US results was 7.57 min (range: 5.15-12.10 min), while the median duration of US examinations without a radiologist-patient consultation of US results was 7.34 min (range: 3.45-14.32 min), without any significant difference (P = 0.637). Conclusion: A radiologist-patient consultation of imaging findings after neck US decreases patient anxiety, is desired by most patients, and does not significantly prolong total examination time
Point-of-care ultrasonography:Downstream utilization of and diagnostic (dis)agreements with additional cross-sectional imaging
OBJECTIVES: Point-of-care ultrasonography (POCUS), defined as ultrasonography (US) performed and interpreted by the clinician, is increasingly performed. This study aimed to determine the frequency of and reasons why clinicians of the emergency department request cross-sectional imaging after POCUS and how often radiologists experience diagnostic (dis)agreements. METHODS: This retrospective study included a consecutive series of 503 patients who underwent POCUS at the emergency department of a tertiary care center. RESULTS: Downstream cross-sectional imaging was performed in 77 (15.3%) of 503 POCUS examinations. Reasons for additional cross-sectional imaging were, in order of decreasing frequency: suspicion of pathology that was not assessed with POCUS in 46 cases (59.7%), confirmation of conclusive POCUS findings in 21 cases (27.3%), inconclusive POCUS (i.e. insufficient visualization of the structure of interest to make a diagnosis, despite an attempt of the POCUS operator) in 7 cases (9.6%), a combination of inconclusive POCUS and suspicion of pathology that was not assessed with POCUS in 2 cases (2.6%), and clarification of incidental findings on POCUS in 1 case (1.3%). In the 21 cases that underwent additional cross-sectional imaging to confirm POCUS findings, POCUS agreed with additional cross-sectional imaging in 19 (90.5%) and disagreed in 2 (9.5%) cases. CONCLUSIONS: The use of POCUS appears to not cause any considerable downstream overutilization of cross-sectional imaging. In addition, radiologists experience few diagnostic disagreements when asked to perform second opinion cross-sectional imaging. Future studies with more homogeneous datasets in terms of POCUS operators are required to confirm our results
Radionuclide Imaging of Fungal Infections and Correlation with the Host Defense Response
The human response to invading fungi includes a series of events that detect, kill, or clear the fungi. If the metabolic host response is unable to eliminate the fungi, an infection ensues. Some of the host response's metabolic events to fungi can be imaged with molecules labelled with radionuclides. Several important clinical applications have been found with radiolabelled biomolecules of inflammation. 18F-fluorodeoxyglucose is the tracer that has been most widely investigated in the host defence of fungi. This tracer has added value in the early detection of infection, in staging and visualising dissemination of infection, and in monitoring antifungal treatment. Radiolabelled antimicrobial peptides showed promising results, but large prospective studies in fungal infection are lacking. Other tracers have also been used in imaging events of the host response, such as the migration of white blood cells at sites of infection, nutritional immunity in iron metabolism, and radiolabelled monoclonal antibodies. Many tracers are still at the preclinical stage. Some tracers require further studies before translation into clinical use. The application of therapeutic radionuclides offers a very promising clinical application of these tracers in managing drug-resistant fungi
Requests for radiologic imaging:Prevalence and determinants of inadequate quality according to RI-RADS
PURPOSE: To determine the prevalence and determinants of radiologic imaging requests that are of inadequate quality according to the Reason for exam Imaging Reporting and Data System (RI-RADS). METHODS: This study included a random sample of 673 radiologic examinations performed at a tertiary care center. The quality of each imaging request was graded according to RI-RADS. Ordinal regression analysis was performed to determine the association of RI-RADS grade with patient age, gender, and hospital status, indication for imaging, requesting specialty, imaging modality, body region, time of examination, and relationship with previous imaging within the past one year. RESULTS: RI-RADS grades A (adequate request), B (barely adequate request), C (considerably limited request), and D (deficient request) were assigned to 159 (23.6 %), 166 (24.7 %), 214 (31.8 %), and 134 (19.9 %) of cases, respectively. Indication for imaging, requesting specialty, and body region were independently significantly associated with RI-RADS grades. Specifically, routine preoperative imaging (odds ratio [OR]: 3.422, P = 0.030) and transplantation imaging requests (OR: 8.710, P = 0.000) had a higher risk of poorer RI-RADS grades, whereas infection/inflammation as indication for imaging (OR: 0.411, P = 0.002), pediatrics as requesting specialty (OR: 0.400, P = 0.007), and head (OR: 0.384, P = 0.017), spine (OR: 0.346, P = 0.016), and upper extremity (OR: 0.208, P = 0.000) as body regions had a lower risk of poorer RI-RADS grades. CONCLUSION: The quality of radiologic imaging requests is inadequate in >75 % of cases, and is affected by several factors. The data from this study can be used as a baseline and benchmark for further investigation and improvement
The integrated nuclear medicine and radiology residency program in the Netherlands:strengths and potential areas for improvement according to nuclear medicine physicians and radiologists
PURPOSE: To evaluate the Dutch integrated nuclear medicine and radiology residency program from the perspective of nuclear medicine physicians and radiologists. METHODS: A survey was distributed among nuclear medicine physicians and radiologists in hospitals that participate in the Dutch integrated nuclear medicine and radiology training program. RESULTS: A total of 139 completed questionnaires were included. Nuclear medicine physicians (n = 36) assigned a mean score of 5.7 ± 2.0, and radiologists (n = 103) assigned a mean score of 6.5 ± 2.8 (on a 1-10 scale) to the success of the integrated training program in their hospital. On multiple regression, female gender of the survey participant (B = 2.22, P = 0.034), musculoskeletal radiology as subspecialty of the survey participant (B = 3.36, P = 0.032), and the survey participant's expectancy of resident's ability to handle workload after completion of residency were significantly associated with perceived success of the integrated training program (B = 1.16, P = 0.023). Perceived strengths of the integrated training program included broadening of expertise, a better preparation of future imaging specialists for hybrid imaging, increased efficiency in training residents, and increased efficiency in multidisciplinary meetings. Perceived weaknesses of the integrated training program included reduced exposure to nuclear medicine, less time for research and innovation, and concerns about its international recognition. CONCLUSION: This study provided insights into the experiences of nuclear medicine physicians and radiologists with the Dutch integrated nuclear medicine and radiology residency program, which may be helpful to improve the program and similar residency programs in other countries
Medical knowledge and clinical productivity:independently correlated metrics during radiology residency
OBJECTIVE: To determine the association between medical knowledge relevant to radiology practice (as measured by the Dutch radiology progress test [DRPT]) and clinical productivity during radiology residency. METHODS: This study analyzed the results of 6 DRPTs and time period–matched clinical production points of radiology residents affiliated to a tertiary care academic medical center between 2013 and 2016. The Spearman correlation analysis was performed to determine the association between DRPT percentile scores and average daily clinical production points. Linear regression analyses were performed to determine the association of DRPT percentile scores with average daily clinical production points, adjusted for age and gender of the radiology resident, and postgraduate year. RESULTS: Eighty-four DRPTs with time period–matched clinical production points were included. These 84 DRPTs were made by 29 radiology residents (18 males and 11 females) with a median age of 31 years (range: 26–38 years). The Spearman correlation coefficient between DRPT percentile scores and average daily clinical production points was 0.550 (95% confidence interval: 0.381–0.694) (p < 0.001), indicating a significant moderate positive association. On multivariate analysis, average daily clinical production points (β coefficient of 0.035, p = 0.003), female gender of the radiology resident (β coefficient of 12.690, p = 0.001), and postgraduate year (β coefficient of 10.179, p < 0.001) were significantly associated with DRPT percentile scores. These three independent variables achieved an adjusted R(2) of 0.527. CONCLUSION: Clinical productivity is independently associated with medical knowledge relevant to radiology practice during radiology residency. These findings indicate that clinical productivity of a resident could be a potentially relevant metric in a radiology training program. KEY POINTS: • There is a significant moderate correlation between medical knowledge relevant to radiology practice and clinical productivity during radiology residency. • Medical knowledge relevant to radiology practice remains independently associated with clinical productivity during radiology residency after adjustment for postgraduate year and gender. • Clinical productivity of a resident may be regarded as a potentially relevant metric in a radiology training program
Use of population input functions for reduced scan duration whole-body Patlak F-18-FDG PET imaging
Abstract: Whole-body Patlak images can be obtained from an acquisition of first 6 min of dynamic imaging over the heart to obtain the arterial input function (IF), followed by multiple whole-body sweeps up to 60 min pi. The use of a population-averaged IF (PIF) could exclude the first dynamic scan and minimize whole-body sweeps to 30–60 min pi. Here, the effects of (incorrect) PIFs on the accuracy of the proposed Patlak method were assessed. In addition, the extent of mitigating these biases through rescaling of the PIF to image-derived IF values at 30–60 min pi was evaluated. Methods: Using a representative IF and rate constants from the literature, various tumour time-activity curves (TACs) were simulated. Variations included multiplication of the IF with a positive and negative gradual linear bias over 60 min of 5, 10, 15, 20, and 25% (generating TACs using an IF different from the PIF); use of rate constants (K 1, k 3, and both K 1 and k 2) multiplied by 2, 1.5, and 0.75; and addition of noise (μ = 0 and σ = 5, 10 and 15%). Subsequent Patlak analysis using the original IF (representing the PIF) was used to obtain the influx constant (K i) for the differently simulated TACs. Next, the PIF was scaled towards the (simulated) IF value using the 30–60-min pi time interval, simulating scaling of the PIF to image-derived values. Influence of variabilities in IF and rate constants, and rescaling the PIF on bias in K i was evaluated. Results: Percentage bias in K i observed using simulated modified IFs varied from − 16 to 16% depending on the simulated amplitude and direction of the IF modifications. Subsequent scaling of the PIF reduced these K i biases in most cases (287 out of 290) to < 5%. Conclusions: Simulations suggest that scaling of a (possibly incorrect) PIF to IF values seen in whole-body dynamic imaging from 30 to 60 min pi can provide accurate Ki estimates. Consequently, dynamic Patlak imaging protocols may be performed for 30–60 min pi making whole-body Patlak imaging clinically feasible
Delayed Effects of a Single Dose Whole-Brain Radiation Therapy on Glucose Metabolism and Myelin Density:a Longitudinal PET Study
Purpose: Radiotherapy is an important treatment option for brain tumors, but the unavoidable irradiation of normal brain tissue can lead to delayed cognitive impairment. The mechanisms involved are still not well explained and, therefore, new tools to investigate the processes leading to the delayed symptoms of brain irradiation are warranted. In this study, positron emission tomography (PET) is used to explore delayed functional changes induced by brain irradiation. Materials and methods: Male Wistar rats were subjected to a single 25-Gy dose of whole brain X-ray irradiation, or sham-irradiation. To investigate delayed effects of radiation on cerebral glucose metabolism and myelin density, 18F-fluorodeoxyglucose (18F-FDG) PET scans were performed at baseline and on day 64 and 94, whereas N-11C-methyl-4,4′-diaminostilbene (11C-MeDAS) PET scans were performed at baseline and on day 60 and 90 post-irradiation. In addition, the open field test (OFT) and novel spatial recognition (NSR) test were performed at baseline and on days 59 and 89 to investigate whether whole brain irradiation induces behavioral changes. Results: Whole-brain irradiation caused loss of bodyweight and delayed cerebral hypometabolism, with 18F-FDG uptake in all brain regions being significantly decreased in irradiated rat on day 64 while it remained unchanged in control animals. Only amygdala and cortical brain regions of irradiated rats still showed reduced 18F-FDG uptake on day 94. 11C-MeDAS uptake in control animals was significantly lower on days 60 and 90 than at the baseline, suggesting a reduction in myelin density in young adults. In irradiated animals, 11C-MeDAS uptake was similarly reduced on day 60, but on day 90 tracer uptake was somewhat increased and not significantly different from baseline anymore. Behavioral tests showed a similar pattern in control and irradiated animals. In both groups, the OFT showed significantly reduced mobility on days 59 and 89, whereas the NSR did not reveal any significant changes in spatial memory over time. Interestingly, a positive correlation between the NSR and 11C-MeDAS uptake was observed in irradiated rats. Conclusions: Whole-brain irradiation causes delayed brain hypometabolism, which is not accompanied by white matter loss. Irradiated animals showed similar behavioral changes over time as control animals and, therefore, cerebral hypometabolism could not be linked to behavioral abnormalities. However, spatial memory seems to be associated with myelin density in irradiated rats
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