Impact of advanced modeled iterative reconstruction on interreader agreement in coronary artery measurements

ObjectivesTo evaluate the influence of advanced modeled iterative reconstruction (ADMIRE) on coronary artery computed tomography angiography (cCTA) measurements in comparison to filtered back projection (FBP).Material and methodsPhantom scans and coronary CTA studies of 27 patients were acquired with a third generation dual-source CT scanner. Images were reconstructed using FBP and ADMIRE. Phantom measurements were used as reference standard. In patient studies, representative axial slices of each coronary artery segment without (n = 308) and with coronary plaques (n = 40) were assessed in identical positions for comparison of FBP and ADMIRE reconstructions. Image analyses included quality assessment, phantom and coronary artery measurements, plaque analysis, and interreader agreement of two independent and blinded readers.ResultsMean image noise was lower on ADMIRE reconstructions with 31.3 ± 9.9 HU compared to 55.9 ± 15.7 HU on FBP reconstructions (p < 0.001). Measurement precision and interreader agreement of both observers were assessed satisfactorily on phantom images in comparison to the full width half maximum method. In patients, correlation of lumen diameters of both observers improved using ADMIRE with a Pearson’s r = 0.987 (95% confidence interval [CI], 0.983–0.989; p < 0.001) compared to FBP images with r = 0.939 (95% CI, 0.924–0.951; p < 0.001). Applying ADMIRE, agreement of both observers for lumen diameter measurements significantly increased (p < 0.001). This was also observed for the degree of stenosis (p < 0.001) with r = 0.560 using FBP (95% CI, 0.301–0.742) and with r = 0.818 using ADMIRE (95% CI, 0.680–0.900). Plaque density measurements correlated closely with a Pearson’s r of 0.951 in FBP (95% CI, 0.909–0.974) and 0.967 in ADMIRE (95% CI, 0.939–0.983).ConclusionsAdvanced modeled iterative reconstruction significantly improves coronary artery assessment in coronary CTA in comparison to FBP by improved image quality due to image noise removal. This renders improved interobserver agreement for coronary lumen diameter and degree of stenosis measurements without influencing mean plaque attenuation.     

A BMI-adjusted ultra-low-dose CT angiography protocol for the peripheral arteries—Image quality,diagnostic accuracy and radiation exposure

ObjectivesTo investigate radiation exposure, objective image quality, and the diagnostic accuracy of a BMI-adjusted ultra-low-dose CT angiography (CTA) protocol for the assessment of peripheral arterial disease (PAD), with digital subtraction angiography (DSA) as the standard of reference.MethodsIn this prospective, IRB-approved study, 40 PAD patients (30 male, mean age 72 years) underwent CTA on a dual-source CT scanner at 80 kV tube voltage. The reference amplitude for tube current modulation was personalized based on the body mass index (BMI) with 120 mAs for [BMI ≤ 25] or 150 mAs for [25 < BMI ≤ 30]. Iterative image reconstruction was applied. The presence of significant stenoses (>70%) was assessed by two readers independently and compared to subsequent DSA. Radiation exposure was assessed with the computed tomography dose index (CTDIvol) and the dosis-length product (DLP). Objective image quality was assessed via contrast- and signal-to-noise ratio (CNR and SNR) measurements. Radiation exposure and image quality were compared between the BMI groups and between the BMI-adjusted ultra-low-dose protocol and the low-dose institutional standard protocol (ISP).ResultsThe BMI-adjusted ultra-low-dose protocol reached high diagnostic accuracy values of 94% for Reader 1 and 93% for Reader 2. Moreover, in comparison to the ISP, it showed significantly (p < 0.001) lower CTDIvol (1.97 ± 0.55 mGy vs. 4.18 ± 0.62 mGy) and DLP (256 ± 81 mGy x cm vs. 544 ± 83 mGy x cm) but similar image quality (p = 0.37 for CNR). Furthermore, image quality was similar between BMI groups (p = 0.86 for CNR).ConclusionsA CT protocol that incorporates low kV settings with a personalized (BMI-adjusted) reference amplitude for tube current modulation and iterative reconstruction enables very low radiation exposure CTA, while maintaining good image quality and high diagnostic accuracy in the assessment of PAD.     

CT angiography for planning transcatheter aortic valve replacement using automated tube voltage selection: Image quality and radiation exposure

PurposeTo assess image quality and accuracy of CT angiography (CTA) for transcatheter aortic valve replacement (TAVR) planning performed with 3rd generation dual-source CT (DSCT).Material and methodsWe evaluated 125 patients who underwent TAVR-planning CTA on 3rd generation DSCT. A two-part protocol was performed including retrospectively ECG-gated coronary CTA (CCTA) and prospectively ECG-triggered aortoiliac CTA using 60 mL of contrast medium. Automated tube voltage selection and advanced iterative reconstruction were applied. Effective dose (ED), signal-to-noise (SNR) and contrast-to-noise ratios (CNR) were calculated. Five-point scales were used for subjective image quality analysis. In patients who underwent TAVR, sizing parameters were obtained.ResultsImage quality was rated good to excellent in 97.6% of CCTA and 100% of aortoiliac CTAs. CTA studies at >100 kV showed decreased objective image quality compared to 70–100 kV (SNR, all p ≤ 0.0459; CNR, all p ≤ 0.0462). Mean ED increased continuously from 70 to >100 kV (CCTA: 4.5 ± 1.7 mSv–13.6 ± 2.9 mSv, all p ≤ 0.0233; aortoiliac CTA: 2.4 ± 0.9 mSv–6.8 ± 2.7 mSv, all p ≤ 0.0414). In 39 patients TAVR was performed and annulus diameter was within the recommended range in all patients. No severe cardiac or vascular complications were noted.Conclusion3rd generation DSCT provides diagnostic image quality in TAVR-planning CTA and facilitates reliable assessment of TAVR device and delivery option while reducing radiation dose.     

Diagnostic value of cone beam computed tomography (CBCT) in occult scaphoid and wrist fractures

ObjectiveEvaluate the diagnostic value of cone beam computed tomography (CBCT) for scaphoid and wrist fractures that are missed on standard radiographs.Materials and methodsBetween September 2014 and October 2015, we prospectively enrolled 49 patients with a clinically suspected scaphoid fracture following an acute injury but had normal radiographs. Each patients underwent radiographs, CBCT and (magnetic resonance imaging) MRI within 7 days of the initial injury event. Both exam were evaluated independently by two radiologists.ResultsFor scaphoid cortical fractures CBCT sensitivity is 100% (95% CI: 75%–100%), specificity 97% (95% CI: 83%–100%). CBCT diagnosed all 24 corticals wrist fractures, corresponding to a sensitivity of 100% (95% CI: 83%–100%), specificity of 95% (95% CI: 75%–100%). Kappa agreement rate between the two radiologists was K = 0.95 (95% CI: 0.85–1) for scaphoid fractures and K = 0.87 (95% CI: 0.73–1) for wrist fractures.ConclusionsCBCT is superior to radiographs for diagnosing occult cortical fractures. Because of its low radiation dose, we believe that CBCT can be used in current practice as a replacement or supplement to radiographs to detect these fractures and optimize the cost-effectiveness ratio by limiting the number of needless immobilizations.     

Transplant renal artery stenosis: Evaluation with contrast-enhanced ultrasound

ObjectiveTo assess the efficacy of contrast-enhanced ultrasound (CEUS) in depicting transplant renal artery stenosis (TRAS).Materials and methodsSeventy-eight patients (56 men and 22 women; aged 36 ± 12.2 years) who were suspected of TRAS due to either Doppler ultrasound (DUS) abnormalities or difficult control of blood pressure and/or persistent deterioration of renal function were enrolled to perform CEUS. The reference standard for the TRAS diagnoses was computed tomography angiography (CTA). The diagnostic performance of DUS and CEUS parameters was assessed by the area under the receiver operating characteristic curve (AUC).ResultsTRAS was diagnosed in 32 out of 78 cases by CTA. The AUC, accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of CEUS in predicting TRAS were 0.92, 92.3%, 87.5%, 95.7%, 93.3%, and 91.7%, respectively. CEUS rectified 13 (28.3%) false-positive cases on DUS, which were confirmed by CTA. Compared to DUS parameters, CEUS showed the highest AUC, statistically significant differences of AUC were found (P = 0.006–0.039), except for that of the PSV ratio in the main transplant renal artery to that in interlobar artery (PSV-ratio) (AUC: 0.92 versus 0.86, P = 0.422). However, CEUS showed a significantly higher specificity (95.7% versus 76.1%, P = 0.008) and the same sensitivity compared to PSV-ratio.ConclusionsCEUS is superior to DUS in depicting TRAS. Moreover, our results suggest that CEUS might potentially be used as a noninvasive tool to spare many patients from unnecessary CTA.     

MR Enterography in paediatric patients with obscure gastrointestinal bleeding

ObjectivesTo evaluate the performance of Magnetic Resonance enterography (MRE) in the diagnostic work-up of children presenting with obscure gastrointestinal bleeding (OGIB).Materials and methodsFrom January 2014 to January 2016, a single-centre prospective study was performed on all children between 0 and 16 years of age referred to the radiology department for OGIB. Each child underwent MRE examination after negative oesophagogastroduodenoscopy and ileocolonoscopy. MRE results were recorded. All patients proceeded to the related gold standard for diagnostic confirmation.Results25 patients (mean age 10.8 ± 4.5 years, range 4 months to 16 years) were included. MRE was diagnostic in 76% (19 of 25). The most frequent diagnoses were intestinal polyp (28%) and Meckel’s diverticulum (16%). Sensitivity and specificity of MRE were 86% and 100% respectively. There were no reported complications during any of the examinations.ConclusionMRE is a safe and accurate imaging modality in the evaluation of paediatric OGIB. Its diagnostic capability is comparable to current evidence for capsule endoscopy in this patient group. Further research with larger sample sizes and standardized control groups is warranted to improve our understanding of MRE in this application.     

Imaging modalities in the diagnosis of pancreatic adenocarcinoma: A systematic review and meta-analysis of sensitivity,specificity and diagnostic accuracy

BackgroundPancreatic cancer, primarily pancreatic ductal adenocarcinoma (PDAC), accounts for 2.4% of cancer diagnoses and 5.8% of cancer death annually. Early diagnoses can improve 5-year survival in PDAC. The aim of this systematic review was to determine the sensitivity, specificity and diagnostic accuracy values for MRI, CT, PET&PET/CT, EUS and transabdominal ultrasound (TAUS) in the diagnosis of PDAC.MethodsA systematic review was undertaken to identify studies reporting sensitivity, specificity and/or diagnostic accuracy for the diagnosis of PDAC with MRI, CT, PET, EUS or TAUS. Proportional meta-analysis was performed for each modality.ResultsA total of 5399 patients, 3567 with PDAC, from 52 studies were included. The sensitivity, specificity and diagnostic accuracy were 93% (95% CI = 88–96), 89% (95% CI = 82–94) and 90% (95% CI = 86–94) for MRI; 90% (95% CI = 87–93), 87% (95% CI = 79–93) and 89% (95% CI = 85–93) for CT; 89% (95% CI = 85–93), 70% (95% CI = 54–84) and 84% (95% CI = 79–89) for PET; 91% (95% CI = 87–94), 86% (95% CI = 81–91) and 89% (95% CI = 87–92) for EUS; and 88% (95% CI = 86–90), 94% (95% CI = 87–98) and 91% (95% C = 87–93) for TAUS.ConclusionThis review concludes all modalities, except for PET, are equivalent within 95% confidence intervals for the diagnosis of PDAC.     

Comprehensive physical fitness and high blood pressure in children and adolescents: A national cross-sectional survey in China

ObjectivesTo assess the association between comprehensive physical fitness and high blood pressure (HBP) among Chinese children and adolescents.DesignNational cross-sectional surveys.Methods214,301 school students’ data aged 7−18 years was extracted in 2014. Six components of physical fitness (forced vital capacity, standing long jump, sit-and-reach, body muscle strength, 50 m dash and endurance running) were measured, standardized and aggregated as a summary physical fitness indicator (PFI). HBP, systolic HBP (SHBP) and diastolic HBP (DHBP) were defined according to sex-, age- and height-specific references in China.ResultsThe prevalence of HBP, SHBP and DHBP was 8.6%, 4.7% and 5.7%, respectively, and PFI was −0.9 in Chinese children and adolescents. A significant negative association between the PFI and HBP was observed with adjusted prevalence of HBP (10.8% (95% CI: 10.4–11.2) to 7.6% (95% CI: 7.3–8.0), P_trend < 0.001), SHBP (5.7% (95% CI: 5.4–6.1) to 4.4% (95% CI: 4.1–4.6), P_trend < 0.001), and DHBP (7.6% (95% CI: 7.2–7.9) to 4.6% (95% CI: 4.3–4.9), P_trend < 0.001) and their ORs (HBP: 0.87(95% CI: 0.82–0.93) to 0.68(95% CI: 0.64–0.73), P_trend < 0.001; SHBP: 0.86(95% CI: 0.79–0.94) to 0.75(95% CI:0.69–0.82), P_trend < 0.001; DHBP: 0.85(95% CI: 0.79–0.92) to 0.59(95% CI: 0.54–0.64), P_trend < 0.001) declined with the increase in PFI. Stratified nutritional status exhibited a similar negative association between PFI and HBP, SHBP and DHBP in children with normal weight, overnutrition, and undernutrition. Stand long jump, body muscle strength, 50 m dash, and endurance running, had a negative association with HBP, SHBP and DHBP, but forced vital capacity had a positive such association. Sit-and-reach and HBP are not significantly associated.ConclusionsPhysical fitness was negatively correlated to the increased HBP in children and adolescents. Comprehensive policies and measures to enhance children and adolescents’ physical fitness are urgently needed through the promotion of physical activity, healthy dietary patterns, and strategies of educational guidelines to reduce schoolwork, which will in turn reduce the cardiovascular burdens in the future.     

The relationship between hip rotation range of movement and low back pain prevalence in amateur golfers: An observational study

ObjectiveTo investigate whether amateur golfers with self-reported low back pain have reduced hip rotation compared to asymptomatic controls.DesignObservational case-control study.SettingData collection took place at 2 amateur golf clubs in southern England.ParticipantsOn initial contact, all participants completed a screening questionnaire used to allocate participants into LBP (n = 28) and control groups (n = 36). LBP group were found to be heavier than controls (t = 2.242, 95% CI 0.763–13.332) but were matched for age, height, handedness, handicap, rounds played per week and years of play.Main outcome measuresPrimary outcome measures were lead and non-lead hip medial and lateral rotation in 0° of flexion as measured by inclinometer. Secondary measures included inter and intra-rater reliability.ResultsThe LBP group had significantly reduced lead hip passive (LBP 21.14 ± 10.17°; controls 31.06 ± 8.06°, t = ?4.228, 95% CI ?14.621–?5.205) and lead hip active medial rotation (LBP 21.46 ± 10.01; controls 28.06 ± 7.49°, t = ?2.908, 95% CI ?11.147–?2.036) compared to controls. No between group differences were found in non-lead hips or any passive or active lateral rotation measures.ConclusionAlthough there is lack of causality between LBP and hip rotation, the deficit in lead leg medial hip rotation in amateur golfers who suffer LBP may be relevant for screening or treatment selection.     

Diagnostic performance of MRI for prediction of muscle-invasiveness of bladder cancer: A systematic review and meta-analysis

PurposeTo review the diagnostic performance of ≥1.5-T MRI for local staging of bladder cancer.MethodsMEDLINE and EMBASE were searched up to February 21, 2017. We included diagnostic accuracy studies published since 2000 that used ≥1.5-T MRI for local staging (≥T2 [muscle-invasive]) in patients with bladder cancer, using pathology as the reference standard. The methodological quality was assessed using Quality Assessment of Diagnostic Accuracy Studies-2. Sensitivity and specificity were pooled and plotted in a hierarchical summary receiver operating characteristics plot. Sensitivity analyses using several clinically relevant covariates were performed.Results24 studies (1774 patients) were included. Pooled sensitivity was 0.92 (95% CI 0.88–0.95) with specificity of 0.87 (95% CI 0.78–0.93). Sensitivity analyses showed that sensitivity estimates were comparable and consistently high across all subgroups, but specificity estimates were variable. Studies using 3-T scanners had higher specificity (0.93 [95% CI 0.86–0.98]) than those using 1.5-T scanners (0.83 [95% CI 0.74–0.98]). Studies using multiparametric MRI (conventional + ≥2 functional sequences) showed the highest accuracy with sensitivity and specificity of 0.94 (95% CI 0.89–1.00) and 0.95 (95% CI 0.89–0.98), respectively.ConclusionsMRI shows good diagnostic performance for predicting muscle-invasiveness of bladder cancer. Multiparametric 3-T MRI seems to improve both sensitivity and specificity.     

Diagnostic performance of computed tomography digital subtraction angiography of the lower extremities during haemodialysis in patients with suspected peripheral artery disease

IntroductionWith intra-arterial digital subtraction angiography (DSA) considered as the gold standard, we compared the diagnostic value of computed tomography angiography (CTA) and computed tomography-digital subtraction angiography (CT-DSA in hemodialysis (HD) patients suspected of having lower limb peripheral artery disease (PAD).MethodsIn this retrospective study, we enrolled 220 HD patients with suspected PAD. CT-DSA images were obtained by subtracting unenhanced images from enhanced images. The research team calculated the area under the curve (AUC), sensitivity, specificity, positive and negative predictive value (PPV, NPV), and recorded the diagnostic accuracy between the CTA and CT-DSA images using the DSA as gold standard. Visual evaluation of calcifications in the peripheral arteries were also compared between CTA and CT-DSA images.ResultsAt the above-knee level, the CTA AUC [95% confidence interval (CI)] was 0.68 (CI 0.64–0.72), sensitivity and specificity were 60 and 81%, PPV and NPV were 85 and 53%, and accuracy was 67%. Below the knee, these values were 0.66 (CI 0.62–0.70), 71 and 79%, 79 and 47%, and 66%. For CT-DSA, above-knee, the AUC [95% CI] was 0.88 (CI 0.85–0.91), sensitivity and specificity were 84 and 92%, PPV and NPV were 89 and 97%, and accuracy was 93%. Below the knee, these values were 0.95 (CI 0.93–0.97), 95 and 93%, 96 and 83%, and 93%. The scores for the visualization of calcification in the peripheral arteries was significantly higher for CT-DSA than CTA (p < 0.05).ConclusionsCT-DSA helps to assess stenotic PAD with high calcification in the lower extremities of HD patients.Implications for practiceOn CT-DSA images, the severity of vascular calcification can be assessed for HD patients suspected of PAD of the lower extremities.     

Can the intensity of physical activity be accurately measured in older adults using questionnaires?

ObjectivesThis study assessed the accuracy of two questionnaires for measuring the duration of physical activity (PA) by intensity compared to an objective measure in older adults.DesignCross-sectional observationMethodsA total of 169 (female = 43.8%) participants aged 73–78 years (mean: 75.1 y; SD: 1.3) wore a SenseWear™ Armband (SWA) for seven-days and reported the duration of PA by intensity with a Physical Activity Recall (PAR) questionnaire and the Active Australia Survey (AAS). In addition, the duration of moderate-to-vigorous-PA (MVPA) and overall active time, weighted for intensity (Total PA; MET: min/week) was assessed. Univariate general linear models were used to compare the questionnaire and SWA measures of PA while controlling for age, sex and education.ResultsThe PAR was associated with SWA moderate intensity PA (b = 0.19; 95% CI 0.03–0.35), MVPA (b = 0.19; 95% CI 0.02–0.37) and Total PA (b = 0.33; 95% CI 0.11–0.55). Although significant correlations were present, the models explained a small proportion of the variance in the SWA variables. The AAS was not associated with the SWA for any PA outcome. There was also significant under-reporting of PA duration for both questionnaires in comparison to the SWA.ConclusionsThe PAR questionnaire may be suitable for determining the effect of greater levels of PA on health outcomes. However, neither questionnaire can be considered valid in determining the duration of PA divided by intensity. In addition, questionnaire and objectively measured PA are not equivalent and absolute measures of PA derived from questionnaires should be interpreted with caution.     

Combining higher-load and lower-load resistance training exercises: A systematic review and meta-analysis of findings from complex training studies

ObjectivesThe aim of the present meta-analytical review was to determine the effectiveness of training programmes combining higher-load and lower-load exercises in one workout (i.e. complex training [CT]) on lower-body performance.DesignSystematic review and meta-analysis.MethodsA search of five electronic databases (PubMed, Web of Science, SportDiscus, CINAHL and Scopus) was conducted to identify all publications up to 7 March 2018. Meta-analyses were performed using a random-effects model with the dependent variables countermovement jump (CMJ) height, squat jump (SJ) height, one-repetition maximum (1-RM) squat performance and sprint time for 5 m, 10 m, 20 m, 30 m and 40 m, respectively.ResultsThe analysis comprised 33 studies and a total of 1064 healthy participants. The meta-analysis revealed that CT is effective in improving CMJ (95% confidence interval [CI] 5.6%–12.3%), SJ (95% CI 8.0%–17.4%), 1-RM squat (95% CI 16.4%–30.7%) and sprint performance (5 m = 95% CI −14.8% to −0.9%, 10 m = 95% CI −6.0% to −2.1%, 20 m = 95% CI −7.4% to −1.4%, 30 m = 95% CI −8.0% to −0.6%). However, when directly compared to traditional training methods, only 1-RM squat strength performance and 20 m sprint time were superior following CT interventions (95% CI 0.2%–13.7% and 95% CI −1.6% to −0.1%, respectively)ConclusionsCT is an acceptable method for improving jump, strength and sprint performance in athletes. Compared to traditional training methods, CT seems to produce superior training effects only for 1-RM squat and 20 m sprint performance; however, these findings were influenced by single studies and should be therefore interpreted with circumspection.     

Diagnostic performance of contrast-enhanced CT-scan in sinusoidal obstruction syndrome induced by chemotherapy of colorectal liver metastases: Radio-pathological correlation

PurposeSinusoidal obstruction syndrome (SOS) is a likely side effect of colorectal liver metastases (CRLM) chemotherapy. This study aimed to assess computed tomography scan (CT-scan) performance for SOS diagnosis for patients receiving neoadjuvant chemotherapy (NC) prior to CRLM surgery, comparing obtained results with pathological gold standard.MethodsPreoperative CT-scans of 67 patients who had received a NC prior to liver resection for CRLM from 2011 to 2016 were retrospectively analysed. Positive diagnosis and severity of SOS were established after consensual review of the slides by three pathologists. Preoperative CT-scans were separately interpreted by two radiologists and evocative signs of SOS were sought, defined according to a literature review and operators experience. In order to identify SOS predictors, univariate analysis and multivariate logistic regression were used to study CT-scan signs and pathological results correlation.ResultsTwenty-nine patient (43%) had an SOS, 22 (33%) were low-grade and 7 (10%) were high-grade. All patient had received a median of 6 cures (3–27) containing Oxaliplatin for 53 (79%) of them. In univariate analysis, hepatic heterogeneity (p < 0.001), puddle-like or micronodular appearance (p < 0.001), peripheral distribution of heterogeneity (p = 0.085), clover-like sign (p = 0.02), splenomegaly (p = 0.0026), spleen volume increase ≥30% (p = 0.04) or splenic length increase ≥15% (p = 0.04), as well as the subjective impression of the observer (P < 0.001) were significantly associated with SOS diagnosis. In multivariate analysis, clover-like sign (OR 1.87, 95% CI 1.18–2.95, p = 0.0081), increase in spleen volume ≥30% (OR 1.29, 95% CI 1.01–1.64, p = 0.04), and the peripheral distribution of heterogeneity (OR 1.53, 95% CI 1.21–1.94, p < 0.001) were independent SOS predictors. The area under the ROC curve was 0.804. The inter-observer agreement for SOS diagnosis was moderate (Kappa = 0.546).ConclusionCT-scan can detect suggestive signs of SOS in patients receiving chemotherapy for CRLM. By integrating clinical and biological information into CT-scan data, it may be fruitful to create a positive diagnostic and severity score for chemotherapy-induced SOS.     

Accelerometer detected lateral sway during a submaximal running test correlates with endurance exercise performance in elite Australian male cricket players

ObjectiveTo identify whether movement patterns during a standardized submaximal running test (SSRT), assessed by accelerometry, were associated with improvements in endurance exercise performance.DesignA retrospective analysis of data collected from the 2018–2019 Australian cricket preseason.MethodsThirty-nine high-performance male cricket players were studied (25 ± 3 years, 82 ± 6 kg, 183 ± 6 cm). SSRT was performed monthly prior to a two kilometre (km) running time trial (2 kmTT). SSRT involved running between markers, positioned twenty metres apart, for three minutes. Foot strikes were timed to a metronome (154 beats/min) to elicit a running speed of ˜eight km/h. Triaxial accelerometers were worn in vests on the upper back and used to assess PlayerLoad medio-lateral vector (PL1D_side%), vertical vector (PL1D_up%) and anterior-posterior vector (PL1D_fwd%) were assessed.Results2 kmTT performance improved over the study period (p < 0.05). PlayerLoad vectors during the first minute of SSRT were not related to 2 kmTT performance (p > 0.23). During the second and third minutes there were positive associations between 2 kmTT (run time) and PL1D_side% (SSRT_2min, β 2.12, p < 0.03, 95% CI: 0.22–4.01; SSRT3_min, β 2.30, p < 0.03, 95% CI:0.32–4.29), but not PL1D_up% (SSRT_2min, β −0.15, p = 0.77, 95% CI: −1.13–0.83; SSRT_3min, β −0.15, p = 0.77, 95% CI: −1.11–0.87) or PL1D_fwd% (SSRT_2min, β −0.45, p = 0.42, 95% CI: −1.49–0.62; SSRT_3min, B−0.45, p = 0.40, 95% CI: −1.51–0.60).ConclusionAssessment of PL1D_side% during the second or third minutes of SSRT may inform how an athlete’s endurance exercise performance is responding to changes in training load.     

Impact on mortality of coronary and non-coronary cardiovascular findings in non-gated thoracic CT by malignancy status

PurposeThe prognostic value of coronary artery calcification (CAC) assessed on non-gated thoracic CT scans has only been explored in population-based studies. We explored the impact of the presence and extension of CAC, as well as of non-coronary atherosclerosis cardiovascular findings (NCACVF) in survival of patients with and without malignancies undergoing clinically indicated non-gated thoracic computed tomography (CT) scans.Materials and methodsBetween August and December 2012, a total of 1.901 patients aged between 35 and 74 years underwent clinically indicated non-gated, non-enhanced thoracic CT scans and followed for mortality through September 2016.ResultsThree hundred and thirty two (17.5%), 250 (13.2%), and 329 (17.3%) patients showed CAC in 1, 2, and 3 vessels, respectively, and the remaining had no CAC. Two hundred and fifty five (13.4%) patients had evidence of extensive calcification (CACSIS > 5). Only 62 (3.3%) had major NCACVF whereas 1635 (86%) had none or minimal NCACVF. After a median follow-up of 3.7 (3.5–3.9) years, 217 (11.4%) deaths occurred. Age [HR 1.03 (95% CI 1.01–1.05), p = 0.001], a history of malignancy [HR 8.04 (95% CI 5.95-10.9), p < 0.0001], and the NCACVF class [HR 1.79 (95% CI 1.45-2.19), p < 0.0001] were identified as independent predictors of death. CACSIS was found an independent predictor of death only among patients without malignancy (HR 1.10 (95% CI 1.02–1.20), p = 0.019).ConclusionsIn this study including clinically indicated non-gated standard thoracic CT scans, survival rates were associated to the CAC extension among patients without malignancy, and to the NCACVF class independent from the malignancy status.     

Incidence and risk factors for race-day jockey falls over fourteen years

ObjectivesTo determine the incidence of, and risk factors for, race-day jockey falls occurring in Thoroughbred flat and jumps (hurdle and steeplechase) racing.DesignRetrospective cohort study.MethodsIncidence rates for race-day jockey falls over 14 racing seasons in New Zealand (n = 421,596 race-day starts) were calculated per 1000 rides. Univariable and multivariable analyses of jockey, horse and race level risk factors were conducted with Poisson regression in a generalized linear mixed model.ResultsMost races (97%, n = 407,948 race starts) were flat racing with 10 races/race-day, whilst most jumps races were longer and had 2 races/race-day. The rate of jockey falls was higher in steeplechase racing (99.9/1000, 95% CI 92.2–108.4) than hurdle (53.2/1000, 95% CI 48.7–58.3) and flat racing (1.2/1000, 95% CI 1.1–1.3, p < 0.001). Experienced athletes (both horse and jockey) had lower IRR. In flat racing, IRR increased linearly with the number of race-day rides by the jockey. In jumps races, IRR increased with a fall in a previous race (IRR 1.5/1000, 95% CI 1.3–1.7, p < 0.001). A shorter jumps race distance reduced the IRR of a jockey fall.ConclusionsAthlete experience was associated with risk of jockey falls. The linearity of race ride number with IRR and longer distance in jumps racing, indicated that cognitive or physiological fatigue may play a role in the risk of a race-day fall. This data highlights the role sport-specific conditioning programmes may have on reducing risk.     

General health complaints and sleep associated with new injury within an endurance sporting population: A prospective study

ObjectivesTo examine the association between subjective health complaints, sleep quantity and new injury within an endurance sport population.DesignProspective cohort study.MethodsNinety-five endurance sporting participants were recruited from running, triathlon, swimming, cycling and rowing disciplines. Over 52-week period participants submitted weekly data regarding subjective health complaints (SHCs) (cardiorespiratory, gastrointestinal and psychological/lifestyle), sleep quantity, training load and new injury episodes. Applying a 7- and 14-day lag period, a shared frailty model was used to explore new injury risk associations with total SHCs and sleep quantity.Results92.6% of 95 participants completed all 52 weeks of data submission and the remainder of the participants completed ≥30 weeks. Seven-day lag psychological/lifestyle SHCs were significantly associated with new injury risk (Hazard ratio (HR) = 1.32; CI 95% = 1.01–1.72, p < 0.04). In contrast, cardiorespiratory (HR = 1.15; CI 95% = 0.99–1.36, p = 0.07) and gastrointestinal (HR = 0.77; CI 95% = 0.56–1.05, p = 0.09) SHCs were not significantly associated with new injury risk. New injury risk had a significant increased association with 14-day lag <7 h/day sleep quantity (HR = 1.51; CI 95% = 2.02–1.13, p < 0.01) and a significant decreased association with >7 h/day sleep quantity (HR = 0.63, CI 95% = 0.45–0.87, p < 0.01. A secondary regression analysis demonstrated no significant association with total SHCs and training load factors (Relative Risk (RR) = 0.08, CI 95% = 0.04–0.21, p = 0.20).ConclusionsTo minimise an increased risk of new injuries within an endurance sporting population, this study demonstrates that psychological/lifestyle subjective health complaints and sleep quantity should be considered. The study also highlights a lag period between low sleep quantity and its subsequent impact on new injury risk. No association was demonstrated between subjective health complaints, sleep quantity and training load factors.     

Exercise-based injury prevention for community-level adolescent cricket pace bowlers: A cluster-randomised controlled trial

ObjectivesTo investigate if an exercise-based injury prevention program (IPP) can modify risk factors for injury in community-level adolescent cricket pace bowlers.DesignCluster-randomised controlled trial.MethodsEight cricket organisations (training two times per week and no previous involvement in a structured IPP) participated in this cluster-randomised trial. Participants were aged 14–17 years, injury free, and not currently performing a rehabilitation/exercise program. Cricket organisations (clusters) were block-randomised by computerised number generation into an intervention group (performed an eight-week IPP at training) or control group (continued their usual cricket activity). Participants were not blinded to group allocation. Strength, endurance, and neuromuscular control were assessed at baseline and follow-up. Treatment effects were estimated using linear mixed models.ResultsSixty-five male adolescent pace bowlers (intervention n = 32 and control n = 33) were randomised. There were significant treatment effects favouring the intervention group for shoulder strength (90°/s) 0.05 (95% CI 0.02–0.09) N m/kg, hamstring strength (60°/s) 0.32 (95% CI 0.13–0.50) N m/kg, hip adductor strength dominant 0.40 (95% CI 0.26–0.55) N m/kg and non-dominant 0.33 (95% CI 0.20–0.47) N m/kg, SEBT reach distance dominant 3.80 (95% CI 1.63–6.04) percent of leg length (%LL) and non-dominant 3.60 (95% CI 1.43–5.78) %LL, and back endurance 20.4 (95% CI 4.80–36.0) seconds. No differences were observed for shoulder strength (180°/s) (p = 0.09), hamstring strength (180°/s) (p = 0.07), lumbopelvic stability (p = 0.90), and single leg squat knee valgus angle (dominant p = 0.06, non-dominant p = 0.15).ConclusionsExercise-based IPPs can modify risk factors for injury in community-level adolescent pace bowlers. Future research is needed to confirm if IPPs can also reduce injury risk in this population.     

Scan time adapted contrast agent injection protocols with low volume for low-tube voltage CT angiography: An in vitro study

PurposeThe aims of this study were twofold. First, we investigated the extent of changes in arterial peak enhancement and changes in the duration of a diagnostic arterial enhancement when small amounts of CA volumes (≤30 mL) were administered at varying tube voltages. Second, we investigated how to optimize CA injection protocols for CT-angiography with long scan times at various tube voltages to achieve optimal vascular enhancement at the lowest reasonable CA dose.Materials and methodsMeasurements were performed with a custom-made dynamic flow phantom. For CTA protocols with a short scan time, we investigated the effect of various tube voltages (70–120 kVp) on the arterial enhancement profile with very small CA volumes (20 and 30 mL of Iobitridol 350 mg I/mL) at a flow rate of 5 mL/s. For CTA protocols with a long scan time, we utilized an optimized multi-bolus technique switching rapidly between 13 “micro-boli” of CA (total, 60 mL) and saline (total, 24 mL) at a flow rate of 4 mL/s. The peak arterial enhancement (PAE) and the time period of diagnostic aortic enhancement ≥200 HU (T200) were analyzed.ResultsFor the short scan time protocols, a diagnostic peak enhancement was achieved using 20 mL of CA at 70 and 80 kVp (PAE: 327 ± 10 and 255 ± 15 HU, respectively) or 30 mL of CA at 70, 80 and 100 kVp (PAE 451 ± 10, 367 ± 9, and 253 ± 15 HU). For the long scan time, the optimized multi-bolus injection protocol extended T200 at 100 kVp by 6 s (40%) compared to a linear injection protocol (21 ± 1 s and 15 ± 1 s, respectively; p < 0.001).ConclusionOptimized CTA protocols comprising alternations of tube voltage and the CA injection protocol can save radiation doses and CA volumes at the same time.