Received Computed Tomography Scans Research Articles

Impact of changes of hospital integrations spanning a decade in Hungary: Modern diagnostic services: CT care based on a Hungarian sample

Introduction, purpose of the study: In Central Europe, in Hungary, the state guarantees access to health care and basic health services partly through the Semmelweis Plan adopted in 2011. The Health Plan aims to optimize and transform the health system. The objectives of hospital integration, as set out in the Plan, started with the state ownership of municipal hospitals in 2012, continued with the launch of integration processes in 2012–2013 and culminated today. The transformation of a health system can have an impact on health services and thus on meeting the needs of the population. We aim to study the effectiveness of integration through access to CT diagnostic testing. Our hypothesis is that integration has resulted in increased access to modern diagnostic services. The specialty under study is computed tomography (CT) diagnostic care. Our research shows that the number of people receiving CT diagnostic care has increased significantly because of integration, which has also brought a number of positive benefits, such as reduced health inequalities, reduced travel time, costs and waiting lists. Test material and method: Our quantitative retrospective research was carried out in the hospital of Kalocsa through document analysis. The research material was comparing two time periods in the Kalocsa site of Bács-Kiskun County, Southern Hungary. The number of patients attending CT examinations by area of duty of care according to postal codes was collected: Pre-integration period 2014.01.01–2017.11.30. (Kalocsa did not have CT equipment, so patients who appeared in Kecskemét Hospital but were under the care of Kalocsa), post-integration period 2017.12.01–2019.12.31. (period after the installation of CT in Kalocsa). The target group of the study consisted of women and men together, aged 0–99 years, who appeared for a CT diagnostic examination. The study sample size was 6721 persons. Linear regression statistics were used to evaluate the results. Based on empirical experience, a SWOT analysis was carried out to further investigate the effectiveness of integration. Results: As a result of the integration, the CT scan machine purchased in the Kalocsa District Hospital has enabled an average of 129.7 patients per month to receive CT scans on site without travelling. The model used is significant, explaining 86% of the change in the number of patients served (F = 43.535; p < 0.001, adjusted R2 = 0.860). The variable of integration in the model is significant, with an average increase in the number of patients served of 129.7 per month (t = 22.686; p < 0.001) following the introduction of CT due to integration. None of the month variables representing seasonal effects were found to be significant, with no seasonal effect on care. The SWOT analysis has clearly identified the strengths, weaknesses, opportunities and threats related to the integration, the main outcome of which is the acquisition of a CT diagnostic tool. Conclusions: Although we only looked at one segment of the evidence for the effectiveness of hospital integration, integration in the study area has had a positive impact on CT availability, reducing disparities in care.

An Innovative Low-dose CT Inpainting Algorithm based on Limited-angle Imaging Inpainting Model.

With the popularity of computed tomography (CT) technique, an increasing number of patients are receiving CT scans. Simultaneously, the public's attention to CT radiation dose is also increasing. How to obtain CT images suitable for clinical diagnosis while reducing the radiation dose has become the focus of researchers. To demonstrate that limited-angle CT imaging technique can be used to acquire lower dose CT images, we propose a generative adversarial network-based image inpainting model-Low-dose imaging and Limited-angle imaging inpainting Model (LDLAIM), this method can effectively restore low-dose CT images with limited-angle imaging, which verifies that limited-angle CT imaging technique can be used to acquire low-dose CT images. In this work, we used three datasets, including chest and abdomen dataset, head dataset and phantom dataset. They are used to synthesize low-dose and limited-angle CT images for network training. During training stage, we divide each dataset into training set, validation set and testing set according to the ratio of 8:1:1, and use the validation set to validate after finishing an epoch training, and use the testing set to test after finishing all the training. The proposed method is based on generative adversarial networks(GANs), which consists of a generator and a discriminator. The generator consists of residual blocks and encoder-decoder, and uses skip connection. We use SSIM, PSNR and RMSE to evaluate the performance of the proposed method. In the chest and abdomen dataset, the mean SSIM, PSNR and RMSE of the testing set are 0.984, 35.385 and 0.017, respectively. In the head dataset, the mean SSIM, PSNR and RMSE of the testing set are 0.981, 38.664 and 0.011, respectively. In the phantom dataset, the mean SSIM, PSNR and RMSE of the testing set are 0.977, 33.468 and 0.022, respectively. By comparing the experimental results of other algorithms in these three datasets, it can be found that the proposed method is superior to other algorithms in these indicators. Meanwhile, the proposed method also achieved the highest score in the subjective quality score. Experimental results show that the proposed method can effectively restore CT images when both low-dose CT imaging techniques and limited-angle CT imaging techniques are used simultaneously. This work proves that the limited-angle CT imaging technique can be used to reduce the CT radiation dose, and also provides a new idea for the research of low-dose CT imaging.

Radiation exposure estimation in pediatric patients during computed tomography imaging procedures

Computed tomography (CT) procedures are the largest source of medical radiation exposure in children and adults. Numerous children undergo high-radiation-dose examinations due to the increasing utilization of CT in children and the wide range of radiation doses. It is therefore necessary to protect pediatric patients, because of their higher sensitivity to ionizing radiation. This study aimed to establish a multicenter cohort of pediatric patients who received CT scans and predict the radiation-related cancer risk. Ninety-five patients who underwent various CT scans [brain 64 (67.4%), chest 14 (14.7%), abdomen 17 (17.9%)] were referred to one of three hospitals. All patients were examined using one of three identical multi-detector CT machines (Toshiba Aquilion 64) according to standard departmental imaging protocols. The average effective doses per scan for brain, chest, and abdominal procedures were 49.7, 34, and 40 mSv, respectively. Dose-reduction measures might significantly decrease the number of radiation-induced malignancies in children.

Identification of Bias in Ordering Further Imaging in Ethnic Groups With Indeterminate Ultrasound for Appendicitis.

BackgroundRecent studies have shown a higher incidence of complications from acute appendicitis in Hispanic populations. Hispanic ethnicity alone has been shown to be a risk factor. In contrast, one study found little evidence of racial disparities in complication rates. The objective of this study was to identify physician bias regarding whether ethnicity drives further testing after initial radiologic imaging has been obtained in the evaluation of appendicitis in our pediatric emergency department (PED). The use of computed tomography (CT) scan in the diagnosis of appendicitis was compared between Hispanic versus non-Hispanic populations when ultrasound (US) was indeterminate.MethodologyThis is a retrospective cohort study of Hispanic and non-Hispanic patients aged 2-18 who presented to the PED with right lower quadrant abdominal pain over a one-year period (January 1, 2017 to December 29, 2017). Both groups were subdivided into positive, negative, or indeterminate US findings for appendicitis. Each subgroup was analyzed based on those who had CT imaging done.ResultsA total of 471 ultrasounds were performed, 162 Hispanic and 309 non-Hispanic patients. Indeterminate US scans were documented in 90/162 (56%) Hispanic versus 155/309 (50%) non-Hispanic patients. Of those with indeterminate US scans, 30% Hispanic versus 32% non-Hispanic patients received CT scans. Negative US scans were documented in 54/162 (33%) Hispanic versus 102/309 (33%) non-Hispanic patients. Of those with negative US scans, 7% Hispanic versus 5% non-Hispanic patients received CT scans. Chi-square analysis comparing both the proportion of CT scans received for indeterminate US scans (p=0.71) and negative US scans (p=0.52) showed no statistical significance.ConclusionsThere was no significant difference in the number of CT scans ordered for indeterminate US scans between Hispanic and non-Hispanic patients. One can infer that there is no inherent bias toward ordering advanced imaging in Hispanic children based on ethnicity alone.

Incidental Radiology Findings on Computed Tomography Studies in Emergency Department Patients: A Systematic Review and Meta-Analysis

An incidental finding is defined as a newly discovered mass or lesion detected on imaging performed for an unrelated reason. The identification of an incidental finding may be an opportunity for the early detection of a serious medical condition, including a malignancy. However, little is known about the prevalence of incidental findings in the emergency department (ED) setting and the strategies that can be used to mitigate the risk associated with them in the ED. This study aimed to estimate the overall prevalence of incidental findings and to summarize the currently described measures to mitigate the risks associated with incidental findings. On November 22, 2020, a systematic literature search of PubMed, EMBASE, and Scopus was performed for studies that were published in peer-reviewed journals and reported the prevalence of incidental findings in computed tomography (CT) scans in patients in the ED. Patients who received CT scans that included the head, neck, chest, or abdomen/pelvis were included. The study characteristics, overall prevalence of incidental findings, prevalence of incidental findings by body region, and prespecified subgroups were extracted. The criteria used for risk stratification within individual studies were also extracted. Pooled estimates were calculated using a random-effects meta-analysis. A total of 1,385 studies were identified, and 69 studies met the inclusion criteria. The included studies represented 147,763 ED encounters or radiology reports across 16 countries, and 83% of studies were observational, cross-sectional studies. A total of 35 studies (50.7%) were in trauma patients. A large degree of heterogeneity was observed across the included studies. The overall pooled prevalence estimate for any incidental finding was 31.3% (95% confidence interval 24.4% to 39.1%). We found great variation in the methods described to mitigate the risk associated with incidental findings, including a lack of standardized risk stratification, inconsistent documentation practices, and only a small subset of studies describing prospective interventions aimed at improving the recognition and management of incidental findings from the ED. In patients in the ED receiving CT scans, incidental findings are commonly encountered across a broad range of ED chief complaints. This review highlights the existence of great heterogeneity in the definitions used to classify incidental findings. Future studies are needed to determine a clinically feasible categorization standard or terminology for commonly encountered incidental findings in the ED setting to standardize classification and documentation.

The Development of Acute Kidney Injury in Burn Patients Undergoing Computed Tomography With Intravenous Contrast

AbstractAcute kidney injury (AKI) is a major complication of significant burn injuries and a significant cause of patient morbidity and mortality. Patients that sustain traumatic burn injuries may require computed tomography (CT) imaging as part of their initial trauma management. This multicenter retrospective chart review of patients admitted to two level I trauma centers with ≥10% TBSA burns between 2014 and 2017 aims to determine if patients with greater than 10% TBSA burns that received CT imaging with intravenous contrast were more likely to develop acute kidney injury during their admission. A total of 439 patients were included in the study. The average age was 45.3 years and average TBSA was 23.2%. Sixty-seven of the 439 patients underwent CT scans with IV contrast on admission. The rate of AKI between patients who did or did not receive CT scans was not statistically significant (9.1 vs 6.0%, P = 0.40). Patients who developed an AKI had higher TBSA (45.6 vs 21.1%, P < .01), amount of fluids per TBSA given within the first 24 hours (457.4 vs 321.6, P < .01), and mortality (71.1 vs 6.2%, P < .01) than those who did not develop an AKI. There was no significant difference in the development of acute kidney injury in burn patients who received CT scans with IV contrast on admission. Although there is a risk of contrast induced nephropathy, the risk is not increased in burn patients and this should not prevent a thorough evaluation to rule out additional life-threatening injuries in the burn trauma patient.

Prospective evaluation of an evidence-based decision tool to assess pediatric blunt abdominal trauma (BAT).

Computed tomography (CT) is currently the standard for evaluation of intra-abdominal injury (IAI) after BAT. Pediatric patients receiving CT scans based on adult clinical protocols are potentially exposed to unnecessary radiation. The purpose of this study is to determine the rate of CT scans before and after implementation of a pediatric BAT decision tool. We adapted and implemented an evidence-based decision tool for pediatric BAT based on five clinical variables. We reviewed patient charts 18months pre- and post-implementation. Demographics and outcomes were compared using Chi-square and Fisher's exact test, accordingly. The pre and post-implementation groups were uniform when comparing age, sex, mechanism, and Injury Severity Score. The decision tool was utilized in 85% of patients post-implementation. Fewer CT scans were obtained in the post-implementation group (28 vs. 21%, p = 0.215) with no missed injuries or late diagnoses. Implementation of a pediatric BAT decision tool decreased CT usage and radiation exposure without an obvious compromise to patient care. This experience supports the utilization of these tools for the assessment of IAI after BAT and have resulted in more selective use of CT during pediatric BAT in our program.

Using Statistical Measures and Density Maps Generated From Chest Computed Tomography Scans to Identify and Monitor COVID-19 Cases in Radiation Oncology Rapidly.

ObjectivesThis study aimed to evaluate quantitative and qualitative screening measures for anomalous computed tomography (CT) scans in cancer patients with potential coronavirus disease 2019 (COVID-19) as an automated detection tool in a radiation oncology treatment setting.MethodsWe identified a non-COVID-19 cohort and patients with suspected COVID-19 with chest CT scans from February 1, 2020 to June 30, 2020. Lungs were segmented, and a mean normal Hounsfield Unit (HU) histogram was generated for the non-COVID-19 CT scans; these were used to define thresholds for designating the COVID-19-suspected histograms as normal or abnormal. Statistical measures were computed and compared to the threshold levels, and density maps were generated to examine the difference between lungs with and without COVID-19 qualitatively.ResultsThe non-COVID-19 cohort consisted of 70 patients with 70 CT scans, and the cohort of suspected COVID-19 patients consisted of 59 patients with 80 CT scans. Sixty-two patients were positive for COVID-19. The mean HUs and skewness of the intensity histogram discriminated between COVID-19 positive and negative cases, with an area under the curve of 0.948 for positive and 0.944 for negative cases. Skewness correctly identified 57 of 62 positive cases, whereas mean HUs correctly identified 17 of 18 negative cases. Density maps allowed for visualization of the temporal evolution of COVID-19 disease.ConclusionsThe statistical measures and density maps evaluated here could be employed in an automated screening algorithm for COVID-19 infection. The accuracy is high enough for a simple and rapid screening tool for early identification of suspected infection in patients treated with chemotherapy and radiation therapy already receiving CT scans as part of clinical care. This screening tool could also identify other infections that present critical risks for patients undergoing chemotherapy and radiation therapy, such as pneumonitis.

Frequency, Recognition, and Potential Risk Factors of Incidental Findings on Trauma Computed Tomography Scans: A Cross-Sectional Study at an Urban Level One Trauma Center.

Computed tomography (CT) use in injured patients has continuously increased in the past decades. We designed and undertook this study to evaluate the frequency, and potential risks of incidental findings (IFs), and how they were processed in trauma patients receiving CT scans. We retrospectively reviewed CT scans, official CT reports, and basic demographics in trauma patients who received CT scans at our emergency department in 2016. Scans with IFs prompted a detailed review of medical records to determine clinical significance and how they were processed. IFs were classified into three categories: category I (potentially severe condition, in-time management required), category II (not urgent, follow-up needed), and category III (of minor concern). Multivariable logistic regression models were fitted to determine patient characteristics associated with IFs. In the 4,092 scans enrolled, IFs were identified in 649 (15.9%). There were 13 (2.0%) category I, 306 (47.2%) category II, and 330 (50.8%) category III IFs. Patients with IFs were older than those without. No sex-based difference was found. Most (61.5%) of the scans were performed for the head; however, the abdomen had the highest IF prevalence (26.2%). Documentation about IFs was poor; 31% of category I, 91.9% of category II, and 97.0% of category III have no related record. Old age remains the risk predicting the presence of IFs, and every year of increasing age was independently associated with a higher prevalence of IFs (OR: 1.019; 95% CI: 1.015-1.024). IFs are common in trauma CT scans; however, recognition and management remain poor. Abdomen and chest scans, and CT in older patients should remind us of increasing risks of IFs.

The relationship between hospital adoption and use of high technology medical imaging and in-patient mortality and length of stay

PurposeThe purpose of this paper is to investigate the relationship between hospital adoption and use of computed tomography (CT) scanners, and magnetic resonance imaging (MRI) machines and in-patient mortality and length of stay.Design/methodology/approachThis study used panel data (2007–2010) from 124 hospital corporations operating in Ontario, Canada. Imaging use focused on medical patients accounting for 25 percent of hospital discharges. Main outcomes were in-hospital mortality rates and average length of stay. A model for each outcome-technology combination was built, and controlled for hospital structural characteristics, market factors and patient characteristics.FindingsIn 2010, 36 and 59 percent of hospitals had adopted MRI machines and CT scanners, respectively. Approximately 23.5 percent of patients received CT scans and 3.5 percent received MRI scans during the study period. Adoption of these technologies was associated with reductions of up to 1.1 percent in mortality rates and up to 4.5 percent in length of stay. The imaging use–mortality relationship was non-linear and varied by technology penetration within hospitals. For CT, imaging use reduced mortality until use reached 19 percent in hospitals with one scanner and 28 percent in hospitals with 2+ scanners. For MRI, imaging use was largely associated with decreased mortality. The use of CT scanners also increased length of stay linearly regardless of technology penetration (4.6 percent for every 10 percent increase in use). Adoption and use of MRI was not associated with length of stay.Research limitations/implicationsThese results suggest that there may be some unnecessary use of imaging, particularly in small hospitals where imaging is contracted out. In larger hospitals, the results highlight the need to further investigate the use of imaging beyond certain thresholds. Independent of the rate of imaging use, the results also indicate that the presence of CT and MRI devices within a hospital benefits quality and efficiency.Originality/valueTo the authors’ knowledge, this study is the first to investigate the combined effect of adoption and use of medical imaging on outcomes specific to CT scanners and MRI machines in the context of hospital in-patient care.

87 The Development of Acute Kidney Injury in Burn Patients Undergoing Computed Tomography with Intravenous Contrast

Acute kidney injury (AKI) is a major complication of significant burn injuries and may be a significant cause of patient morbidity and mortality. Contrast-induced nephropathy is one of the common causes of acute renal failure in hospitalized patients. Patients that sustain both burn injuries and blunt traumatic injuries may require computed tomography (CT) imaging as part of their initial management. The purpose of this investigation was to determine if patients with greater than 10% TBSA burns that received CT imaging with IV contrast were more likely to develop AKI during their admission. This is a multicenter retrospective chart review of patients admitted to two level I trauma centers with ≥10% TBSA burns between 2014–2017. Patients were excluded if they were admitted for less than 48 hours or died within 48 hours of admission. The electronic medical record was used to extract patient data such as demographics, TBSA, length of stay, baseline and peak creatinine, if a CT scan with IV contrast was done and amount of fluid given over the initial 24 and 48 hours. A total of 443 patients were included in the study. The average age was 45 years. The average TBSA was 23.1%, ranging from 10%-92%. Sixty-eight of the 443 patients underwent CT scans with IV contrast on admission. The rate of AKI in the total population was 8.8%. The rate of AKI between patients who did or did not receive CT scans was not statistically significant (7.4 vs 9.1%). There was no significant difference in the amount of fluids per TBSA given within the first 24 hours between those who developed an AKI and those who did not (460.9 vs 366.7). Patients who received a CT scan had a higher TBSA (29.3 vs 22.0%, p<.01). Patients who developed an AKI had a significantly higher TBSA than those who did not (44.3 vs 21%, p<.0001). Overall mortality was 11.7%. Patients who developed an AKI had a significantly higher mortality than those patients that did not (70.3% vs 6.2%, p<.0001). There was no significant difference in the development of acute kidney injury in burn patients who received CT scans with IV contrast on admission. Although the patients that received IV contrast had a higher TBSA, there was no difference in the amount of IV fluids given in the first 24 hours. The extent of the burn remains a significant risk factor for the development of AKI. Development of AKI in the burn patient is associated with increased mortality. While there is a risk of contrast induced nephropathy, the risk is not increased in burn patients and this should not prevent a thorough evaluation to rule out additional life threatening injuries in the burn trauma patient. Concern for contrast induced nephropathy should not prevent adequate trauma imaging in the burn patient.

Comparative study of computed tomography of normal and lymphoid follicular hyperplasia thymus in myasthenia gravis patients.

The aim of the present study was to evaluate the thymuses of non-thymomatous myasthenia gravis (MG) patients by computed tomography (CT) for differentiating lymphoid follicular hyperplasia (LFH) thymus from normal/involuted thymus in order to assist surgeons in determining whether a non-thymomatous MG patient requires an operation. In the present retrospective review over 10 years, 80 patients who received CT scan and thymectomy at the Affiliated General Hospital of Tianjin Medial University (Tianjin, China) were included. According to the pathological records, 54 of the cases initially detected on CT were confirmed as LFH thymus. Thymic measurements, including anteroposterior and transverse dimensions, width (the longest axis of the lobe on a transverse scan) and thickness (the largest dimension perpendicular to the long axis of the lobe) and CT attenuation of the thymus region, adipose tissue and chest wall musculature in each CT slice were included to assess differences between the LFH group and the normal/involuted thymus group. Although a negative association between patient age and the CT attenuation of the thymus region was identified (r=-0.779, P<0.05, Pearson's correlation test), the LFH thymus group featured nodular changes on CT, while no such changes were observed in the normal/involuted thymus group. The mean age of disease onset in the LFH thymus group was significantly lower than that in the normal thymus group (40.2±17.3 vs. 59.2±9.3 years). Furthermore, significant differences in CT attenuation were identified between the LFH group and the normal/involuted thymus group [-41.21±54.42 vs. -108.23±8.72 Hounsfield units (HU) on unenhanced CT; -25.57±58.65 vs.-117.40±6.22 HU on contrast-enhanced CT]. In the LFH group, the difference in mean CT attenuation between the thymus region and adipose tissue was significant, while no significant difference was observed in the normal/involuted thymus group. In conclusion, CT may be used to distinguish LFH thymus from normal/involuted thymus in MG patients.

188 Impact of Adult Level 1 Trauma Designation on the Timeliness of Pediatric Emergency Department Computed Tomography Scans

Timeliness in the provision of medical care is an essential aspect of patient safety and health care quality. Given the unpredictable nature of the emergency department (ED) with regards to variation in disease acuity and patient volume, it is essential to gather crucial information in a prompt fashion to aid medical decisionmaking and patient disposition. The adult emergency department of our institution was verified as a Level 1 Trauma Center by the American College of Surgeons in December 2015, 24 years after our pediatric emergency department was recognized as a Level 1 Trauma Center. One of the metrics used as an operational benchmark in the ED is imaging interval (time from order of an imaging test to the availability of results). There is a single computed tomography (CT) scanner located in the emergency department, which is utilized by both the adult and pediatric sections. With an anticipated increase in the adult ED patient volume following its new status, we sought to assess the impact of adult Level 1 Trauma designation on the timeliness of pediatric non-trauma CT scans in an emergency department. Retrospective chart review of patients in the pediatric emergency department who had CT scans was performed. We compared CT scan orders of patients over the same 6-month period prior to and after the adult ED Level 1 Trauma verification, and assessed the time from order to completion of CT scans. The months with historically highest trauma volumes were chosen. All pediatric trauma activations were excluded, as well as duplicate orders and scans performed during EMR downtime. Unpaired student t-tests and Chi-squared tests were used for statistical analyses. There were 218 consecutive CT scans analyzed in 2015, and 193 consecutive CT scans in the same time frame in 2016. About half of the CT scans in both years were head imaging studies, and more males were scanned compared to females. The average time for CT completion prior to adult ED Level 1 verification was 39.5 minutes, compared to 55.5 minutes in the same time frame the next year (p<0.0001). Also, the proportion of children receiving CT scans within 60 minutes from order decreased from 81% in 2015 to 65% in 2016. (p=0.0002; 95% CI 7.4 - 24.4). The new designation of adult Level 1 trauma status in our ED was associated with a significant delay (by more than 40%) in performance of non-trauma pediatric CT scans, and decrease in the likelihood of children receiving CT scans within 60 minutes. These findings may have significant clinical and economic ramifications for pediatric patients and hospitals, and represent the potential "collateral damage" of an institution receiving an upgrade of their adult trauma center to Level 1 status.

Follow-up imaging after acute evaluations for pediatric nephrolithiasis: Trends from a National database

Overuse of computed tomography (CT) in the initial evaluation of children with upper urinary tract calculi (UUTC) has been well documented. Follow-up imaging patterns, however, remain undefined. Sequential imaging following an acute episode of UUTC represents additional opportunity for enacting good imaging stewardship, with the optimal goal to reduce unnecessary radiation exposure and cost while ensuring appropriate follow-up. We explored nationwide imaging patterns for children following emergency department (ED) evaluations for UUTC, hypothesizing that initial imaging choice and complicated visits for UUTC increase the risk of follow-up CT scans. Claims from Marketscan (2007-2013), an employer-based dataset of privately insured patients, were used to assess children aged 1-18 years presenting to the ED an acute UUTC event. The primary outcome was any imaging within 90 days. Using logistic regression, odds for follow-up CT or plain film kidney-ureter-bladder/ultrasound (KUB/US) imaging were calculated adjusting for patient demographics, initial imaging modality, need for admission, and return ED visits. A total of 821 children met the inclusion criteria, of whom 261 (31.8%) received no follow-up imaging. Overall follow-up imaging patterns, including the proportions of children receiving CT scans, KUB/US imaging, or no imaging are shown in the Summary Table. Of the children receiving follow-up imaging, KUB/US was obtained in 363 (65.0%) and CT obtained in 197 (35.0%) children. Risk factors for follow-up CT imaging include hospital admission and return ED visits. Children with ureteral calculi and index US evaluation were more likely to receive KUB/US imaging only at follow-up. For children with ureteral calculi, the median time to first follow-up imaging was 9 days (25th-75th percentiles, 2-26 days). One-third of all children with follow-up imaging after an acute presentation for UUTC will receive a CT. Up to 28% of children with a ureteral calculus will not receive any follow-up imaging within 3 months of presentation. These findings suggest imaging strategies for children following acute evaluation for nephrolithiasis are suboptimal in two ways. First, children receive potentially unnecessary additional radiation burden, an alarming finding considering the high rates of CT scan in the index evaluation for these children. Second, many children with ureteral calculi fail to receive follow-up imaging to document stone passage. Our findings identify follow-up imaging as another area for quality improvement within the care of children with UUTC. Clinical pathways directing imaging strategies for pediatric nephrolithiasis should focus on follow-up imaging practices and initial evaluation, especially with for those children presenting with ureteral calculi.

High positive computed tomography yields in the emergency department might not be a positive finding.

There is growing pressure to reduce unnecessary computed tomography (CT) imaging requests that the radiology department receives from the emergency department (ED); however, information on acceptable usage rates and diagnostic yields remains scanty. To describe the indications, clinical categories and positive yield rates of patients receiving CT scans in the ED. A retrospective record review was done of all patients who received CT scans at an urban, adult academic ED during a 4-month period. Primary outcomes were to establish CT scan usage and positive yield rates. Other outcomes included analysis of indications, demographics and anatomical areas scanned. Scans (n=1 010) were analysed. The median age of patients was 36 (range 4 - 93) years. Male patients received 64.3% of all scans, as well as 75.7% of the scans performed for trauma. The majority of the scans were for trauma patients. However, non-trauma patients had a higher positive yield; the non-trauma positive yield rate was 61.8% compared with the trauma positive yield rate of 47.1% (p&lt;0.001). The majority of scans performed were of the head (58%) and neck (20%), with lowest positive yield rates of 48.9% and 17%, respectively. The overall CT scan usage rate was 4.6% and overall positive rate 53.8%. A negative CT scan does not necessarily mean that the test was not indicated. Higher positive yield rates may reflect insufficient use of CT scanning by the ED. Local guidelines should be established to ensure judicious and effective clinical use of CT scans.

Are We Choosing Wisely in Lymphoma? Excessive Use of Surveillance CT Imaging in Patients With Diffuse Large B-cell Lymphoma (DLBCL) in Long-term Remission

IntroductionThe use of surveillance computed tomography (CT) imaging in patients with diffuse large B-cell lymphoma in remission is neither effective nor cost-effective. The American Society of Hematology Choosing Wisely (CW) campaign, in particular, emphasizes the lack of benefit beyond 2 years of completion of therapy. We sought to describe the real-world practice of surveillance imaging. Patients and MethodsWe used population-based health system administrative databases from Ontario, Canada. We studied a cohort of all adult patients ≥ 18 years with diffuse large B-cell lymphoma who received rituximab (R) with CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) between 2004 and 2012. We defined an index date of 2 years after the last dose of RCHOP as the time frame beyond which surveillance imaging would be inappropriate. The cumulative incidence of receiving CT scans after the index date represented the primary outcome of interest. ResultsThe cohort consisted of 2401 patients treated with RCHOP during the study period. The cumulative incidence reached 52.5% (range, 50.4%-54.6%) by 3 years of follow-up. On multivariable analysis, patients with more comorbidities and within certain geographic regions within the province were noted to have increased CT scanning. The cumulative incidence appeared to decrease over the study follow-up period (from 62.4% in 2006 to 48.0% in 2014; P < .001). ConclusionDuring a timeframe in which surveillance imaging is deemed unnecessary by the CW campaign, the practice remains excessive. Regional variations in CT scanning suggest that local practice patterns can be targeted to reduce imaging. A recent decline in scanning may reflect a broadening appreciation for the evidence against surveillance or uptake of the CW campaign.

Computed tomography and magnetic resonance imaging features of the myomatous hepatic angiomyolipoma

Objective To investigate the computed tomography (CT) and magnetic resonance imaging (MRI) features of the myomatous hepatic angiomyolipoma (MHAML). Methods The retrospective cross-setional study was conducted. The clinicopathological data of 22 patients with MHAML who were admitted to the Southwest Hospital of the Third Military Medical University between January 2010 and June 2016 were collected. Patients underwent plain and enhanced scans of CT and MRI, and then received pathological examination after surgical resection or liver puncture and immunohistochemical staining. Observation indicators: (1) findings of CT and MRI, 2 radiologists independently read films; (2) diagnostic consistency of 2 radiologists; (3) results of pathological examination. The Kappa test was used for evaluating the consistency, κ≥0.75 as a good consistency, 0.40<κ<0.75 as a normal consistency and κ≤0.40 as a poor consistency. Results (1) Findings of CT and MRI: of 22 patients, 16 received CT scans and 6 received CT and MRI scans. Tumors of 22 patients were single lesion, showing similar-circular type. Tumors located in the right liver lobe, left liver lobe and caudate lobe were respectively detected in 14, 7 and 1 patients. ① Plain and enhanced scans of CT: tumors of 22 patients showed low density. Twenty patients had clear boundary of tumor and 2 had an unclear boundary. Tumors of 22 patients demonstrated obvious enhancement in arterial phase by enhanced scans of CT, including fast-in and slow-out enhancement in 10 patients and fast-in and fast-out enhancement in 12 patients. The draining veins inside tumors were detected in 12 patients in early arterial phase by enhanced scans of CT. The dilated blood vessels inside tumors were found in 12 patients. The ring enhancement of tumor margin was detected in 16 patients, with formation of small blood vessels involving tumor blood supply. ② MRI scan: tumors of 6 patients presented as low signal on T1WI and high signal on T2WI. Of 6 patients, 5 had clear boundary of tumor and 1 had an unclear boundary. Tumors of 6 patients demonstrated obvious enhancement in arterial phase by enhanced scans of MRI, with a fast-in and fast-out enhancement. The draining veins inside tumors were detected in 3 patients in early arterial phase by enhanced scans of MRI. The dilated blood vessels inside tumors were found in 1 patient. The persistent ring enhancement of tumor margin was detected in 5 patients, with formation of small blood vessels. All the lesions of 6 patients using GD-EOB-DTPA MR contrast-enhanced scan demonstrated restricted diffusion with a high b value (b=800 s/mm2), an average apparent diffusion coefficient of 1.549×10-3 mm2/s (1.209×10-3-1.796×10-3 mm2/s) and low a signal in liver phase. (2) Diagnostic consistency of 2 radiologists: there were good diagnostic consistencies of 2 radiologists in tumor location, density, T1WI, T2WI, bleeding, enhancement method and dilated blood vessels (κ=1.00, 1.00, 1.00, 1.00, 0.82, 0.82, P<0.05). There were normal diagnostic consistencies of 2 radiologists in tumor fat, calcification, component of cystolization, boundary, draining veins and enhancement of tumor margin (κ=0.46, 0.45, 0.64, 0.54, P<0.05). (3) Results of pathological examination: results of pathological examination of tumors from surgical resection of 17 patients and liver puncture of 5 patients showed that smooth muscle cells were the major components, and thick-walled vessels were found in the tumor of 12 patients. Results of immunohistochemical staining showed that anti melanoma specific monoclonal antibody (HMB-45) was positive. Conclusion The persistent enhancement of tumor margin, draining veins in early arterial phase by enhanced scans and dilated blood vessels might play roles in diagnosis of MHAML. Key words: Liver neoplasms; Angiomyolipoma; Myomatous type; Tomography, X-ray computed; Magnetic resonance imaging; GD-EOB-DTPA

Arthroscopic Treatment of Osteochondral Lesions of the Talus With Allograft Cartilage Matrix.

This prospective study evaluated the intermediate-term outcomes of operatively treating primary osteochondral lesions of the talus (OLT) of 1.5 cm2 or smaller with arthroscopic excision, microfracture, and allograft cartilage extracellular matrix (ECM). Between 2012 and 2015, 30 consecutive patients received allograft cartilage ECM at their microfractured OLT of 1.5 cm2 or smaller after failing nonoperative treatment. Preoperative and postoperative function and pain were graded using the Foot and Ankle Ability Measure (FAAM) and a visual analog scale (VAS), respectively. Postoperative imaging was assessed for osteochondral healing and degenerative changes. This included computed tomography (CT) at 6 months from surgery. Data regarding postoperative complications were recorded. All 30 patients that received allograft cartilage ECM for their OLT were evaluated for final follow-up at a mean of 20.2 months. Mean FAAM increased from 51.4 preoperatively to 89.3 of 100 at final follow-up. Mean VAS decreased from 8.1 preoperatively to 1.7 of 10 at final follow-up. These differences between preoperative and postoperative function and pain were statistically significant ( P < .05). At 6 months from surgery, 2 patients (6.7%) received CT scans that revealed incomplete chondral formation at their OLT. At 19 months after surgery, a separate patient (3.3%) developed ankle arthritic changes. Treating OLTs with allograft cartilage ECM has not been previously reported. Using allograft cartilage ECM resulted in a high rate of improvement in ankle function and pain in patients with OLTs. These findings are important as allograft cartilage ECM could be of significant benefit for patients with OLTs. Level III, prospective comparative series.

Simultaneous head and facial computed tomography scans for assessing facial fractures in patients with traumatic brain injury

IntroductionPatients with traumatic brain injury (TBI) may have concomitant facial fractures. While most head injury patients receive head computed tomography (CT) scans for initial evaluation, the objective of our study was to investigate the value of simultaneous facial CT scans in assessing facial fractures in patients with TBI. MethodsFrom January 1, 2015 to December 31, 2015, 1649 consecutive patients presenting to our emergency department (ED) with a TBI who received CT scans using the protocol for head and facial bones were enrolled. The clinical data and CT images were reviewed via a standardized format. ResultsIn our cohort, 200 patients (12.1%) had at least one facial fracture shown on the CT scans. Patients with facial fractures were more likely to have initial loss of consciousness (ILOC; p<0.001), a Glasgow coma scale of 8 or less (p<0.001), moderate or severe degrees of head injury severity scale (p<0.001), positive physical examination findings (p<0.001), and positive CT cranial abnormalities (p<0.001). A total of 166 (83.0%) patients with facial fractures required further facial CT scans instead of conventional head CT scans alone. Surgical intervention was mandatory in 73 (44.0%) of the 166 patients, who more frequently exhibited fractures of the lower third of the face (p<0.001) and orbital fractures (p=0.019). ConclusionsTBI patients with risk factors may have a higher probability of concomitant facial fractures. Fractures of the lower third of the face and orbit are easily overlooked in routine head CT scans but often require surgical intervention. Therefore, simultaneous head and facial CT scans are suggested in selected TBI patients.

COMPUTED TOMOGRAPHIC CHARACTERISTICS OF THE THYROID GLANDS IN EIGHT HYPERTHYROID CATS PRE- AND POSTMETHIMAZOLE TREATMENT COMPARED WITH SEVEN EUTHYROID CATS.

Hyperthyroidism is the most common feline endocrinopathy; thyroid computed tomography (CT) may improve disease detection and methimazole dose selection. Objectives of this experimental pre-post with historical case-control study were to perform thyroid CT imaging in awake or mildly sedated hyperthyroid cats, compare thyroid gland CT appearance in euthyroid and hyperthyroid cats pre- and postmethimazole treatment, and determine whether thyroid size or attenuation correlate with methimazole dose needed for euthyroidism. Premethimazole treatment, eight hyperthyroid cats received CT scans from the head to heart, which were compared to CT of seven euthyroid cats. Total thyroxine levels were monitored every 3-4 weeks. Postmethimazole CT was performed 30 days after achieving euthyroid status. Computed tomography parameters recorded included thyroid length, width, height, attenuation, and heterogeneity. Median time between CT was 70 days (53-213 days). Mild sedation was needed in five hyperthyroid cats premethimazole, and none postmethimazole. Thyroid volume was significantly larger in hyperthyroid cats compared to euthyroid cats (785.0 mm3 vs. 154.9 mm3 ; P = 0.002) and remained unchanged by methimazole treatment (-4.5 mm3; P = 0.50). Thyroid attenuation and heterogeneity decreased with methimazole treatment (96.1 HU vs. 85.9 HU; P = 0.02. 12.4 HU vs. 8.1 HU; P = 0.009). Methimazole dose ranged from 2.5 to 10 mg daily with a positive correlation between pretreatment thyroid gland volume and dose needed to achieve euthyroidism (P = 0.03). Euthyroid and hyperthyroid cats are easily imaged awake or mildly sedated with CT. Methimazole in hyperthyroid cats significantly lowers thyroid attenuation and heterogeneity, but not size.