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Health claims databases offer opportunities for studies on large populations of patients with kidney disease and health outcomes in a non-experimental setting. Among others, their unique features enable studies on healthcare costs or on longitudinal, epidemiological data with nationwide coverage. However, health claims databases also have several limitations. Because clinical data and information on renal function are often lacking, the identification of patients with kidney disease depends on the actual presence of diagnosis codes only. Investigating the validity of these data is therefore crucial to assess whether outcomes derived from health claims data are truly meaningful. Also, one should take into account the coverage and content of a health claims database, especially when making international comparisons. In this article, an overview is provided of international health claims databases and their main publications in the area of nephrology. The structure and contents of the Dutch health claims database will be described, as well as an initiative to use the outcomes for research and the development of the Dutch Kidney Atlas. Finally, we will discuss to what extent one might be able to identify patients with kidney disease using health claims databases, as well as their strengths and limitations.

Although the biological characteristics of uterine fibroids (UF) have implications for therapy choice and effectiveness, there is limited MRI data about these characteristics. Currently, the Funaki classification and Scaled Signal Intensity (SSI) are used to predict treatment outcome but both screening-tools appear to be suboptimal. Therefore, multiparametric and quantitative MRI was studied to evaluate various biological characteristics of UF. 87 patients with UF underwent an MRI-examination. Differences between UF tissues and myometrium were investigated using T2-mapping, Apparent Diffusion Coefficient (ADC) maps with different b-value combinations, contrast-enhanced T1-weighted and T2-weighted imaging. Additionally, the Funaki classification and SSI were calculated. Significant differences between myometrium and UF tissue in T2-mapping (p = 0.001), long-TE ADC low b-values (p = 0.002), ADC all b-values (p

AIMS: To evaluate the association between flash glucose monitoring (FLASH) frequency and glycemic parameters during real-life circumstances in the Netherlands.METHODS: Obtained glucose readings were de-identified and uploaded to a dedicated database when FLASH reading devices were connected to internet. Data between September 2014 and March 2020, comprising 16,331 analyzable readers (163,762 sensors) were analyzed. Scan rate per reader was determined and each reader was sorted into 20 equally sized rank ordered groups (n=817 each).RESULTS: Users performed a median of 11.5 [IQR 7.7-16.7] scans per day. Those in the lowest and highest ventiles scanned on average 3.7 and 40.0 times per day and had an eHbA1c of 8.6% (71 mmol/mol) and 6.9% (52 mmol/mol), respectively. Increasing scan rates were associated with more time in target range (3.9-10 mmol/L), less time in hyperglycemia (>10 mmol/L), and a lower standard deviation of glucose. An eHbA1c of 7.0% (53 mmol/mol) translated in approximately 65% time in target range, 30% time in hyperglycemia and 5% time in hypoglycemia (CONCLUSIONS: These outcomes among Dutch FLASH users suggest that with higher scan rate glycemic control improves.

Objective: To evaluate the impact of radiation dose reduction on image quality in patients with metal-on-metal total hip arthroplasties (THAs) using model-based iterative reconstruction (MBIR) combined with orthopaedic metal artefact reduction (O-MAR). Materials and methods: Patients with metal-on-metal THAs received a pelvic CT with a full (FD) and a reduced radiation dose (RD) with −20%, −40%, −57%, or −80% CT radiation dose respectively, when assigned to group 1, 2, 3, or 4 respectively. FD acquisitions were reconstructed with iterative reconstruction, iDose 4 . RD acquisitions were additionally reconstructed with iterative model-based reconstruction (IMR) levels 1–3 with different levels of noise suppression. CT numbers, noise and contrast-to-noise ratios were measured in muscle, fat and bladder. Subjective image quality was evaluated on seven aspects including artefacts, osseous structures, prosthetic components and soft tissues. Results: Seventy-six patients were randomly assigned to one of the four groups. While reducing radiation dose by 20%, 40%, 57%, or 80% in combination with IMR, CT numbers remained constant. Compared with iDose 4 , the noise decreased (p < 0.001) and contrast-to-noise ratios increased (p < 0.001) with IMR. O-MAR improved CT number accuracy in the bladder and reduced noise in the bladder, muscle and fat (p < 0.01). Subjective image quality was rated lower on RD IMR images than FD iDose 4 images on all seven aspects (p < 0.05) and was not related to the applied radiation dose reduction. Conclusion: In RD IMR with O-MAR images, CT numbers remained constant, noise decreased and contrast-to-noise ratios between muscle and fat increased compared with FD iDose 4 with O-MAR images in patients with metal-on-metal THAs. Subjective image quality reduced, regardless of the degree of radiation dose reduction.

Introduction Frozen section diagnoses of borderline ovarian tumors are not always straightforward and a borderline frozen section diagnosis with suspicious features of invasive carcinoma (reported as “at least borderline” or synonymous descriptions) presents us with the dilemma of whether or not to perform a full surgical staging procedure. By performing a systematic review and meta‐analysis, the prevalence of straightforward borderline and “at least borderline” frozen section diagnoses, as well as proportion of patients with a final diagnosis of invasive carcinoma in these cases, were assessed and compared, as quantification of this dilemma may help us with the issue of this clinical decision. Material and methods PubMed, EMBASE and Cochrane library databases were searched and studies discussing “at least borderline” frozen section diagnoses were included in the review. Numbers of specific frozen section diagnoses and subsequent final histological diagnoses were extracted and pooled analysis was performed to compare the proportion of patients diagnosed with invasive carcinoma following borderline and “at least borderline” frozen section diagnoses, presented as risk ratio and risk difference with 95% confidence intervals (95% CI). Results Of 4940 screened records, eight studies were considered eligible for quantitative analysis. A total of 921 women was identified and 230 (25.0%) of these women were diagnosed with “at least borderline” ovarian tumor at the time of frozen section. Final histological diagnoses were reported in five studies, including 61 women with an “at least borderline” diagnosis and 290 women with a straightforward borderline frozen section diagnosis. Twenty‐five of 61 women (41.0%) of the “at least borderline” group had invasive cancer at final diagnosis, compared with 28 of 290 women (9.7%) of the straightforward borderline frozen section group (risk difference −0.34, 95% CI −0.53 to −0.15; relative risk 0.25, 95% CI 0.13–0.50). Conclusions Women diagnosed with “at least borderline” frozen section diagnoses were found to have a higher chance of carcinoma upon final diagnosis when compared with women with a straightforward borderline frozen section diagnosis (41.0% vs 9.7%). Especially in the serous subtype, and after preoperative consent, full staging during initial surgery might be considered in these cases to prevent a second surgical procedure.

Aims: To identify factors predicting HbA1c reduction in patients with diabetes mellitus (DM) using FreeStyle Libre Flash Glucose Monitoring (FSL-FGM).Methods: Data from a 12-month prospective nation-wide FSL registry were used and analysed with multivariable regression. For the present study we included patients with hypoglycaemia unawareness or unexpected hypoglycaemias (n = 566) and persons who did not reach acceptable glycaemic control (HbA1c > 70 mmol/mol (8.5%)) (n = 294). People with other indications for use, such as sensation loss of the fingers or individuals already using FSL-FGM or rtCGM, were excluded (37%).Results: Eight hundred and sixty persons (55% male with a mean age of 46.7 (+/- 16.4) years) were included. Baseline HbA1c was 65.1 (+/- 14.5) mmol/mol (8.1 +/- 1.3%), 75% of the patients had type 1 DM and 37% had microvascular complications. Data concerning HbA1c was present for 482 (56.0%) at 6 months and 423 (49.2%) persons at 12 months. A significant reduction in HbA1c (>= 5 mmol/mol (0.5%)) was present in 187 (22%) persons. For these persons, median HbA1c reduction was -9.0 [-13.0, -4.0] mmol/mol (-0.82 [-1.19, -0.37]%) at 6 months and -9.0 [-15.0, -7.0] mmol/mol (-0.82 [-1.37, -0.64]%) at 12 months. In multi-variable regression analysis with age, gender and SF-12 physical and mental component scores as covariates, only baseline HbA1c was significant: -0.319 (SE 0.025; p Conclusions: Among the variables we analysed in the present study, only high HbA1c at baseline predicts significant HbA1c reduction during FSL-CGM use.

Objectives To provide a systematic review of brain injury and altered brain development in moderate-late preterm (MLPT) infants as compared to very preterm and term infants. Study design A systematic search in five databases was performed in January 2020. Original research papers on incidence of brain injury and papers using quantitative data on brain development in MLPT infants were selected. The Johanna Briggs Institute ‘Critical Appraisal Checklist for Studies Reporting Prevalence Data’ was used for quality appraisal. Data extraction included: imaging modality, incidences of brain injury, brain volumes, 2D-measurements and diffusivity values. Results In total, 24 studies were eligible. Most studies had a moderate quality. Twenty studies reported on the incidence of brain injury in MLPT infants. The incidence of intraventricular hemorrhage (IVH) ranged from 0.0% to 23.5% and of white matter injury (WMI) from 0.5% to 10.8%. One study reported the incidence of arterial infarction (0.3%) and none of cerebellar hemorrhage. Eleven studies compared incidences of brain injury between MLPT infants and very preterm or term infants. Five studies reported signs of altered brain development in MLPT infants. Conclusions The incidences of IVH and WMI in MLPT infants varied widely between studies. Other abnormalities were sparsely reported. Evidence regarding a higher or lower incidence of brain injury in MLPT infants compared to very preterm or term infants is weak due to moderate methodological quality of reported studies. There is limited evidence suggesting a difference in brain development between MLPT and term infants.

OBJECTIVES Three commonly used techniques for localization of nonpalpable breast cancer are radioactive seed localization (RSL), wire-guided localization (WGL) and radioguided occult lesion localization (ROLL). In this study, we analysed the surgical margins of these three techniques. METHODS Women diagnosed with nonpalpable breast cancer undergoing breast-conserving surgery with one of the above-mentioned techniques were retrospectively included. The primary outcome parameter was tumour-free margin rate. Secondary outcomes were re-excision rate, recurrence of disease and volume of removed tissue. RESULTS In total, 272 women were included in whom RSL (n=69), WGL (n=76) or ROLL (n=137) was performed. RSL showed a higher tumour-free margin rate [64 (92.8%)] compared with WGL [51 (67.1%)] and ROLL [113 (82.5%)] (P=0.001). In our multivariable analysis, RSL showed a higher tumour-free margin rate as well compared with WGL (P=0.036) and ROLL (P=0.049). Also, fewer re-excisions were encountered using RSL [5 (7.2%)] compared with WGL [13 (17.1%)] and ROLL [15 (10.9%)] (P=0.171). In 11 patients (WGL n=2, ROLL n=9), recurrence of disease occurred, despite a radical excision. The mean resection volumes were comparable within the three groups. CONCLUSION RSL results in a higher tumour-free margin rate in nonpalpable breast tumours compared with WGL and ROLL. Therefore, we prefer using RSL in nonpalpable breast tumours.

With increasing use of both flash glucose monitoring and real-time continuous glucose monitoring and the reliance of users on these readings, accuracy is important, in particular during intensive exercise. We investigated the performance of the FreeStyle Libre 1 flash glucose monitor and the Guardian Connect EnliteTM real-time continuous glucose monitor by comparing readings with self-monitored blood glucose values during intensive exercise.

Objectives The aim of this study was to assess the effect of hybrid iterative reconstruction and post processing on emphysema quantification in low-dose CT scans of COPD patients using pulmonary function tests (PFT) as a reference. Methods CT scans of 23 COPD patients diagnosed with GOLD I or higher were reconstructed with iDose4 level 1 to 7 in IntelliSpace Portal (ISP) 6 and 7. ISP7 was used with and without specific denoising filter for COPD. The extent of emphysema was measured as percentage of lung voxels with attenuation < − 950 Hounsfield units (%LAA-950). The correlation between %LAA-950 and PFT, age, BMI, pack years, and the Clinical COPD Questionnaire (CCQ) and Medical Research Council dyspnea scale (MRC) was determined. Results Denoising significantly reduced %LAA-950 as was demonstrated by lower %LAA-950 in ISP7 with denoising filter and a significant reduction in %LAA-950 with higher iDose4 levels. All PFT except forced vital capacity (FVC) were significantly inversely correlated with %LAA-950. There was a trend toward a stronger correlation at higher iDose4 levels. %LAA-950 was also significantly correlated with BMI, GOLD class, and CCQ scores. Conclusions Our study showed that hybrid iterative reconstruction and use of post processing denoising can optimize the use of emphysema quantification in CT scans as a complimentary diagnostic tool to stage COPD in addition to PFT.

IntroductionThe FreeStyle Libre is a flash glucose monitoring (FSL-FGM) system. Compared with finger-prick based self-monitoring of blood glucose, FSL-FGM may provide benefits in terms of improved glycemic control and decreased disease burden.MethodsProspective nationwide registry. Participants with diabetes mellitus (DM) used the FSL-FGM system for a period of 12 months. End points included changes in HbA1c, hypoglycemia, health-related quality of life (12-Item Short Form Health Surveyv2 (SF-12v2) and 3-level version of EuroQol 5D (EQ-5D-3L)), a specifically developed patient-reported outcome measures (PROMs) questionnaire, diabetes-related hospital admission rate and work absenteeism. Measurements were performed at baseline, and after 6 months and 12 months.Results1365 persons (55% male) were included. Mean age was 46 (16) years, 77% of participants had type 1 DM, 16% type 2 DM and 7% other forms. HbA1c decreased from 64 (95%CI 63 to 65) mmol/mol to 60 (95%CI 60 to 61) mmol/mol with a difference of −4 (95% CI −6 to 3) mmol/mol. Persons with a baseline HbA1c >70 mmol/mol had the most profound HbA1c decrease: −9 (95% CI −12 to to 5) mmol/mol. EQ-5D tariff (0.03 (95%CI 0.01 to 0.05)), EQ-VAS (4.4 (95%CI 2.1 to 6.7)) and SF-12v2 mental component score (3.3 (95%CI 2.1 to 4.4)) improved. For most, PROMs improved. Work absenteeism rate (/6 months) and diabetes-related hospital admission rate (/year) decreased significantly, from 18.5% to 7.7% and 13.7% to 2.3%, respectively.ConclusionsReal world data demonstrate that use of FSL-FGM results in improved well-being and decreased disease burden, as well as improvement of glycemic control.

Purpose To evaluate the incidence and characteristics of brain lesions in moderate-late preterm (MLPT) infants, born at 32–36 weeks’ gestation using cranial ultrasound (cUS) and magnetic resonance imaging (MRI). Methods Prospective cohort study carried out at Isala Women and Children’s Hospital between August 2017 and November 2019. cUS was performed at postnatal day 3–4 (early-cUS), before discharge and repeated at term equivalent age (TEA) in MLPT infants born between 32+0 and 35+6 weeks’ gestation. At TEA, MRI was also performed. Several brain lesions were assessed e.g. hemorrhages, white matter and deep gray matter injury. Brain maturation was visually evaluated. Lesions were classified as mild or moderate-severe. Incidences and confidence intervals were calculated. Results 166 MLPT infants were included of whom 127 underwent MRI. One or more mild lesions were present in 119/166 (71.7 %) and moderate-severe lesions in 6/166 (3.6 %) infants on cUS and/or MRI. The most frequent lesions were signs suggestive of white matter injury: inhomogeneous echogenicity in 50/164 infants (30.5 %) at early-cUS, in 12/148 infants (8.1 %) at TEA-cUS and diffuse white matter signal changes (MRI) in 27/127 (23.5 %) infants. Cerebellar hemorrhage (MRI) was observed in 16/127 infants (12.6 %). Delayed maturation (MRI) was seen in 17/117 (13.4 %) infants. Small hemorrhages and punctate white matter lesions were more frequently detected on MRI than on cUS. Conclusions In MLPT infants mild brain lesions were frequently encountered, especially signs suggestive of white matter injury and small hemorrhages. Moderate-severe lesions were less frequently seen.

To explore ipsilateral and contralateral acetabular roof bone stock density in unilateral large head MoM THA whether there is a significant lower acetabular bone stock in the hip with a metal-on-metal (MoM) total hip replacement compared to the contralateral side. Second part of this study is to examine if there are any associates with regard to potential bone stock density difference. A database of 317 patients with unilateral metal-on-metal (MoM) total hip replacements was set up retrospectively for this study. On computed tomography scans, conducted after a relative short in situ time period averaging 2.8 years, regions-of-interests were drawn in the trabecular bone of the acetabulum to measure average Hounsfield Units (HU). HU differences were calculated and tested by Wilcoxon signed-rank test. Univariate analysis was conducted to examine associates of potential bone loss. In a population of 317 patients (156 male, 161 female) with an average age of 61.9 +/- 7.8, the median HU on the side of the MoM replacement was 123.3 (7.6-375.4). On the contralateral side, median HU was 144.7 (-0.4 to 332.8). The median HU difference was 21.4 after a mean post-operative in situ time of 2.8 years. The Wilcoxon signed-rank test proved a significant difference (p

Objectives: To quantify the combined use of iterative model-based reconstruction (IMR) and orthopaedic metal artefact reduction (O-MAR) in reducing metal artefacts and improving image quality in a total hip arthroplasty phantom. Methods: Scans acquired at several dose levels and kVps were reconstructed with filtered back-projection (FBP), iterative reconstruction (iDose4) and IMR, with and without O-MAR. Computed tomography (CT) numbers, noise levels, signal-to-noise-ratios and contrast-to-noise-ratios were analysed. Results: Iterative model-based reconstruction results in overall improved image quality compared to iDose4 and FBP (P < 0.001).Orthopaedicmetal artefact reduction is most effective in reducing severe metal artefacts improving CT number accuracy by 50%, 60%, and 63% (P < 0.05) and reducing noise by 1%, 62%, and 85% (P < 0.001) whereas improving signal-to-noise-ratios by 27%, 47%, and 46% (P < 0.001) and contrastto-noise-ratios by 16%, 25%, and 19% (P < 0.001) with FBP, iDose4 , and IMR, respectively. Conclusions: The combined use of IMR and O-MAR strongly improves overall image quality and strongly reduces metal artefacts in the CT imaging of a total hip arthroplasty phantom.

Objective: To compare quantitative measures of image quality, in terms of CT number accuracy, noise, signal-to-noise-ratios (SNRs), and contrast-to-noise ratios (CNRs), at different dose levels with filtered-back-projection (FBP), iterative reconstruction (IR), and model-based iterative reconstruction (MBIR) alone and in combination with orthopedic metal artifact reduction (O-MAR) in a total hip arthroplasty (THA) phantom. Materials and methods: Scans were acquired from high- to low-dose (CTDIvol: 40.0, 32.0, 24.0, 16.0, 8.0, and 4.0 mGy) at 120- and 140- kVp. Images were reconstructed using FBP, IR (iDose4 level 2, 4, and 6) and MBIR (IMR, level 1, 2, and 3) with and without O-MAR. CT number accuracy in Hounsfield Units (HU), noise or standard deviation, SNRs, and CNRs were analyzed. Results: The IMR technique showed lower noise levels (p < 0.01), higher SNRs (p < 0.001) and CNRs (p < 0.001) compared with FBP and iDose4 in all acquisitions from high- to low-dose with constant CT numbers. O-MAR reduced noise (p < 0.01) and improved SNRs (p < 0.01) and CNRs (p < 0.001) while improving CT number accuracy only at a low dose. At the low dose of 4.0 mGy, IMR level 1, 2, and 3 showed 83%, 89%, and 95% lower noise values, a factor 6.0, 9.2, and 17.9 higher SNRs, and 5.7, 8.8, and 18.2 higher CNRs compared with FBP respectively. Conclusions: Based on quantitative analysis of CT number accuracy, noise values, SNRs, and CNRs, we conclude that the combined use of IMR and O-MAR enables a reduction in radiation dose of 83% compared with FBP and iDose4 in the CT imaging of a THA phantom.

Purpose To quantify the impact of prosthesis material and design on the reduction of metal artefacts in total hip arthroplasties using virtual monochromatic dual-layer detector Spectral CT imaging. Methods The water-filled total hip arthroplasty phantom was scanned on a novel 128-slice Philips IQon dual-layer detector Spectral CT scanner at 120-kVp and 140-kVp at a standard computed tomography dose index of 20.0 mGy. Several unilateral and bilateral hip prostheses consisting of different metal alloys were inserted and combined which were surrounded by 18 hydroxyapatite calcium carbonate pellets representing bone. Images were reconstructed with iterative reconstruction and analysed at monochromatic energies ranging from 40 to 200 keV. CT numbers in Hounsfield Units (HU), noise measured as the standard deviation in HU, signal-to-noise-ratios (SNRs) and contrast-to-noise-ratios (CNRs) were analysed within fixed regions-of-interests placed in and around the pellets. Results In 70 and 74 keV virtual monochromatic images the CT numbers of the pellets were similar to 120-kVp and 140-kVp polychromatic results, therefore serving as reference. A separation into three categories of metal artefacts was made (no, mild/moderate and severe) where pellets were categorized based on HU deviations. At high keV values overall image contrast was reduced. For mild/moderate artefacts, the highest average CNRs were attained with virtual monochromatic 130 keV images, acquired at 140-kVp. Severe metal artefacts were not reduced. In 130 keV images, only mild/moderate metal artefacts were significantly reduced compared to 70 and 74 keV images. Deviations in CT numbers, noise, SNRs and CNRs due to metal artefacts were decreased with respectively 64%, 57%, 62% and 63% (p

OBJECTIVE: To evaluate the performance of the FreeStyle Libre Flash continuous glucose monitoring (FSL-CGM) system against established central laboratory methods.RESEARCH DESIGN AND METHODS: 20 subjects (8 type 1 diabetes mellitus, 12 type 2 diabetes mellitus) were analyzed. FSL-CGM sensor measurements (inserted in arm and abdomen) were compared with capillary blood glucose results analyzed with StatStrip as semigold standard. The glucose response after a standardized oral glucose load was measured by FSL-CGM and capillary samples analyzed by perchloric acid hexokinase (PCA-HK) method, StatStrip and FSL test strip (FSLC), and a commonly used CGM system (iPro2).RESULTS: FSL-CGM arm sensor readings showed 85.5% of paired readings falling within Clarke Error Grid (ISO 15197:2013) zone A when compared with StatStrip. For FSL-CGM abdomen and FSLC, these percentages were 64% and 98%, respectively. The overall correlation of FSL-CGM in the arm and the StatStrip indicates a performance with lower results with the FSL-CGM in the arm than expected based on the StatStrip in the lower glucose ranges, and higher results than expected in the higher ranges. Following a standardized glucose load, a slower rise in glucose level was observed for FSL-CGM arm as compared with PCA-HK, StatStrip, FSLC, and iPro2 during the first 45-60 min after glucose load ingestion.CONCLUSIONS: Certain matters need attention while using the FSL-CGM in daily life including the observed lower values in the lower ranges, and the underestimation of the effect of a meal on glucose response. These effects of such deviations can partly be overcome by optimizing the available user instructions.TRIAL REGISTRATION NUMBER: TC5348; results.

BACKGROUND: It has been suggested that arnica can reduce postoperative edema and ecchymosis associated with cosmetic surgical procedures and improve outcome. Despite a high incidence of arnica use among upper blepharoplasty patients, evidence to support its treatment effect is lacking. The authors performed a randomized, double-blind, placebo-controlled trial to investigate the efficacy of arnica ointment after upper blepharoplasty. METHODS: One hundred thirty-six bilateral upper blepharoplasty patients were randomized between arnica ointment 10% and placebo ointment. In both study arms, one periorbital area was designated as the treatment side (either arnica or placebo ointment), and the contralateral side served as an untreated (no ointment) internal control. As the primary endpoint, the overall periorbital appearance as based on light photography and judged by a medical and nonmedical panel, was assessed after 3 days, 7 days, and 6 weeks. Secondary endpoints were swelling, ecchymosis, erythema, pain, and patient satisfaction with recovery and outcome. RESULTS: There was no significant difference between arnica and placebo in overall judgment of periorbital appearance 3 days, 7 days, and 6 weeks after surgery. Furthermore, swelling, ecchymosis, erythema, pain, and patient satisfaction with recovery and outcome did not differ between arnica and placebo. Postoperative outcome in untreated eyelids was not different from eyelids treated with either arnica or placebo on any of the studied outcome measures. CONCLUSION: The authors' study demonstrates that topical arnica ointment after upper blepharoplasty does not improve postoperative outcome. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, II.

Purpose: Quantification of the effect of O-MAR on decreasing metal artefacts caused by large head metal on metal total hip arthroplasty (MoM THA) in a dedicated phantom setup of the hip. Background: Pathological reactions of the hip capsule on Computed tomography (CT) can be difficult to diagnose due to different metal artefacts. The O-MAR algorithm deploys an iterative loop where the metal sinogram is identified, extracted, and subsequently serves as a mask to correct the measured sinogram. Main goal of this study is to quantify the ability of the O-MAR technique to correct deviation in medullary bone attenuation caused by streak artefacts from the large-head MoM THA embedded in a phantom. Secondary goal is to evaluate the influence of O-MAR on CNR. Methods: The phantom was designed as a Perspex box (PMMA) containing water and a supplementary MOM THA surrounded by Perspex columns comprising calibrated calcium pellets. Each column contains 200 mg of hydroxyapatite/calcium carbonate to simulate healthy bone tissue. Scans were obtained with and without a MoM THA at different dose levels. Different reconstructions were made with filter A, iDose(4) level 5 and with and without O-MAR. The scans without the prosthesis were used as the baseline. Information about the attenuation in Hounsfield units, image noise in standard deviation within the ROI's were extracted and the CNR was calculated. Results: Pellet L0 and R0 (proximal of the MoM THA) were defined as reference, lacking any disturbance by metal artefacts; L5, L6 and L8 were respectively visually categorized as 'light' 'medium' and 'heavy disturbance'. Significant improvements in attenuation deviation caused by metal artefact were 43, 68 and 32 %, for respectively pellet L5, L6 and L8 (p

Objectives To determine if mandatory adherence to a diagnostic protocol increases the rate of computed tomography pulmonary angiographies (CTPAs) positive for pulmonary embolism (PE)—the so-called diagnostic yield. Further, we aim to identify factors associated with this diagnostic yield. Methods We included all patients with suspected PE requiring CTPA from 9 January 2014 t0 3 June 2014. The requesting physicians were forced to follow diagnostic workup for PE by calculating a Wells score and, if necessary, determining D-dimer level. The percentage of positive CTPA scans was calculated and compared with our previous cohort (Walen et al. Insights Imaging 2014;5(2):231–236). Odds ratios were calculated as a measure of association between dichotomous variables and CTPA findings. Results Of 250 scans, 74 were positive (29.6 % [95 % CI, 24.3-35.5 %]) and 175 were negative (70 %). The percentage positive scans increased with 6.6 % and the percentage negative scans decreased with 3.1 %. This change was statistically significant (p = 0.001). Independent clinical predictors of diagnostic yield were previous deep venous thrombosis (DVT) (OR, 3.22; p = 0.013) and clinical signs of DVT (OR, 2.71; p = 0.012). Chronic obstructive pulmonary disease (COPD) was negatively associated with PE (OR, 0.33; p = 0.045). Conclusions This study shows that mandatory adherence to a diagnostic protocol increases the yield of CTPA for PE in our centre. Main Messages • Mandatory adherence to diagnostic protocol increases the yield of CTPA for PE • Previous DVT and signs of DVT were associated with a higher yield • No patients with a low Wells score and a low D-dimer had PE

Study ObjectiveTo determine the diagnostic accuracy of ultrasound for detecting distal forearm fractures.MethodsA systematic review and diagnostic meta-analysis was performed according to the PRISMA statement. We searched MEDLINE, Web of Science and the Cochrane Library from inception to September 2015. All prospective studies of the diagnostic accuracy of ultrasound versus radiography as the reference standard were included. We excluded studies with a retrospective design and those with evidence of verification bias. We assessed the methodological quality of the included studies with the QUADAS-2 tool. We performed a meta-analysis of studies evaluating ultrasound to calculate the pooled sensitivity and specificity with 95% confidence intervals (CI95%) using a bivariate model with random effects. Subgroup and sensitivity analysis were used to examine the effect of methodological differences and other study characteristics.ResultsOut of 867 publications we included 16 studies with 1,204 patients and 641 fractures. The pooled test characteristics for ultrasound were: sensitivity 97% (CI95% 93-99%), specificity 95% (CI95% 89-98%), positive likelihood ratio (LR) 20.0 (8.5-47.2) and negative LR 0.03 (0.01-0.08). The corresponding pooled diagnostic odds ratio (DOR) was 667 (142-3,133). Apparent differences were shown for method of viewing, with the 6-view method showing higher specificity, positive LR, and DOR, compared to the 4-view method.ConclusionThe present meta-analysis showed that ultrasound has a high accuracy for the diagnosis of distal forearm fractures in children when used by proper viewing method. Based on this, ultrasound should be considered a reliable alternative, which has the advantages of being radiation free.