The proton density–weighted, in-phase stack-of-stars (PDIP-SOS) MRI technique provides calcification visualization in peripheral artery disease (PAD). This study sought to investigate the diagnostic accuracy of a combined non-contrast quiescent-interval slice-selective (QISS) MRA and PDIP-SOS MRI protocol for the detection of PAD, in comparison with CTA and digital subtraction angiography (DSA). Twenty-six prospectively enrolled PAD patients (70 ± 8 years) underwent lower extremity CTA and 1.5-T or 3-T PDIP-SOS/QISS MRI prior to DSA. Two readers rated image quality and graded stenosis (≥ 50%) on QISS MRA without/with calcification visualization. Sensitivity, specificity, and area under the curve (AUC) were calculated against DSA. Calcification was quantified and compared between MRI and non-contrast CT (NCCT) using paired t test, Pearson’s correlation, and Bland-Altman analysis. Image quality ratings were significantly higher for CTA compared to those for MRA (4.0 [3.0–4.0] and 3.0 [3.0–4.0]; p = 0.0369). The sensitivity and specificity of QISS MRA, QISS MRA with PDIP-SOS, and CTA for ≥ 50% stenosis detection were 85.4%, 92.2%, and 90.2%, and 90.3%, 93.2%, and 94.2%, respectively, while AUCs were 0.879, 0.928, and 0.923, respectively. A significant increase in AUC was observed when PDIP-SOS was added to the MRA protocol (p = 0.0266). Quantification of calcification showed significant differences between PDIP-SOS and NCCT (80.6 ± 31.2 mm3 vs. 88.0 ± 29.8 mm3; p = 0.0002) with high correlation (r = 0.77, p < 0.0001) and moderate mean of differences (− 7.4 mm3). QISS MRA combined with PDIP-SOS MRI provides improved, CTA equivalent, accuracy for the detection of PAD, although its image quality remains inferior to CTA. • Agreement in stenosis detection rate using non-contrast quiescent-interval slice-selective MRA compared to DSA improved when calcification visualization was provided to the readers. • An increase was observed in both sensitivity and specificity for the detection of ≥ 50% stenosis when MRI-based calcification assessment was added to the protocol, resulting in a diagnostic accuracy more comparable to CTA. • Quantification of calcification showed statistical difference between MRI and non-contrast CT; however, a high correlation was observed between the techniques.

Objective: To evaluate the effects of age, race, payer status, and socioeconomic status on complications and comorbidities in children with cholesteatoma. Methods: An analysis of the Kids' Inpatient Database was performed on cases of cholesteatoma between 2006 and 2016, along with associated complications or co-morbidities and surgical interventions. Results: 1552 cases of pediatric cholesteatoma represented 5.6 cases per 100,000 total discharges over the study period. The mean age was 9.9 (+/- 5.4) years. Compared to children in the 4th age quartile, those in the 1st age quartile had decreased risk of conductive hearing loss (OR 0.64 [0.42-0.99]), venous thrombosis (OR 0.24 [0.06-0.88]), intracranial abscess (OR 0.35 [0.13-0.96]), and facial nerve palsy (0.44 [0.20-0.97]), but increased risk of chronic otitis media (OR 2.24 [1.23-4.10]). Compared to children identified as Other race, children identified as Black had increased risk of acute otitis media (OR 9.20 [1.35-62.78]). Both children identified as Black (OR 9.90 [1.48-66.35]) or Hispanic (OR 6.24 [1.01-38.51]) had increased risk of facial nerve palsy. Relative to children in the 4th income quartile, children in the 1st income quartile had increased risk of acute mastoiditis (OR 1.87 [1.15-3.03]) and subperiosteal abscess (OR 6.75 [2.22-20.56]). Children in the 2nd income quartile were less likely to receive ossicular chain surgery (OR 0.31 [0.13-0.72]). Conclusion: Differences pertaining to age, race, payer status, and socioeconomic status exist in the presentation and surgical management of children hospitalized with cholesteatoma. Older children are at increased risk of intracranial complications. Patients of Black and Hispanic race might have a higher risk of facial nerve palsy. Compared to children of higher income families, those from lower income families more frequently develop acute mastoiditis and subperiosteal abscess. Providers should be mindful of these risk factors when caring for children with cholesteatoma.

Introduction: The majority of Americans report using social media, but there is limited research describing impact of social media on academic performance and reading. Our objectives were to describe the association between social media use and reading levels of third-year student pharmacists (P3), describe the association between reading level and pharmacy school admissions data, and assess texts used in the curriculum for readability. Methods: This was a prospective, cohort study. Reading level was determined by a standardized test. Social media data were collected via questionnaire. Admissions data were obtained from the admissions office. Readability of texts was assessed using readability software. Results: Eighty-nine student pharmacists completed the study. The average reading level was 16.4. Students reported using social media for an average of 126 min daily. Students reported using an average of four social media sites and spending 88 min weekly on extracurricular reading. Negligible linear correlations were found between reading level and time spent on social media (rho = 0.063), number of sites used (rho = 0.062), and time spent on extracurricular reading (rho = 0.130). A moderate correlation (rho = 0.524) was found between reading level and Pharmacy College Admission Test (PCAT) score. The average readability of guidelines and textbook chapters were 18.1 +/- 1.0 and 20.4 +/- 0.3, respectively. Conclusions: In P3 students, reading level was not associated with social media use. However, PCAT scores were positively associated with reading level. Furthermore, the readability of assigned texts exceeded the average reading level of the students.

Myocardial T1-mapping has become feasible over the past decade as emerging technological magnetic resonance imaging advances enable increasingly rapid and reliable acquisition techniques. A variety of T1-mapping sequences are in development, with most allowing for the acquisition of a single-slice T1-map in a single breath-hold. The development of these protocols has spurred investigation into a wide range of potential clinical uses, including the characterization of cardiomyopathies. Although native T1-mapping provides superior tissue characterization, postcontrast T1-mapping is still indispensable for extracellular volume quantification. Ongoing and future studies should investigate the reliability, reproducibility, accuracy, and precision of available techniques and establish disease-specific reference values for T1-mapping-based parameters.

Myocardial T1-mapping has become feasible over the past decade as emerging technological magnetic resonance imaging advances enable increasingly rapid and reliable acquisition techniques. A variety of T1-mapping sequences are in development, with most allowing for the acquisition of a single-slice T1-map in a single breath-hold. The development of these protocols has spurred investigation into a wide range of potential clinical uses, including the characterization of cardiomyopathies. Although native T1-mapping provides superior tissue characterization, postcontrast T1-mapping is still indispensable for extracellular volume quantification. Ongoing and future studies should investigate the reliability, reproducibility, accuracy, and precision of available techniques and establish disease-specific reference values for T1-mapping-based parameters.

Objectives The aim of this study was to investigate the minimum iodine delivery rate (IDR) and contrast media (CM) volume required for diagnostic contrast enhancement of 350 HU (Hounsfield units) in the ascending aorta at different kV settings. Methods Dynamic computed tomography acquisitions from 70 to 150 kV were performed in a circulation phantom. First, injections with IDR ranging from 0.1 to 2.0 g I/s were tested for each kV. In the second part, the IDR was held constant, whereas the CM volume was reduced from 50 to 10 mL. Diagnostic aortic peak enhancement for each kV was compared using the Kruskal-Wallis test. P < 0.05 was considered statistically significant. Results The mean aortic peak enhancement for all diagnostic IDRs was 368.7 ± 11.1 HU. Diagnostic IDRs returned similar aortic peak enhancement values for all protocols (all P ≥ 0.18). For the second part of the study, a diagnostic enhancement was yielded by using a minimum of 30 mL of CM for 110 kV, 25 mL for 100 and 90 kV, and 15 mL for 80 and 70 kV. Conclusion Our study suggests that a differentiated approach reducing the CM volume for tube voltages of less than 120 kV and increasing the IDR for higher kV settings seems to be the most effective approach.

To evaluate the influence of inversion time (TI) on the precision of myocardial late gadolinium enhancement (LGE) quantification using synthetic inversion recovery (IR) imaging in patients with myocardial infarction (MI).

Purpose To evaluate image quality and diagnostic accuracy for acute infarct detection and radiation dose of 70 kVp whole brain CT perfusion (CTP) and CT angiography (CTA) reconstructed from CTP source data. Methods Patients were divided into three groups ( n = 50 each): group A, 80 kVp, 21 scanning time points; groups B, 70 kVp, 21 scanning time points; group C, 70 kVp, 17 scanning time points. Objective and subjective image quality of CTP and CTA were compared. Diagnostic accuracy for detecting acute infarct and cerebral artery stenosis ≥ 50 % was calculated for CTP and CTA with diffusion weighted imaging and digital subtraction angiography as reference standards. Effective radiation dose was compared. Results There were no differences in any perfusion parameter value between three groups ( P > 0.05). No difference was found in subjective image quality between three groups ( P > 0.05). Diagnostic accuracy for detecting acute infarct and vascular stenosis showed no difference between three groups ( P > 0.05). Compared with group A, radiation doses of groups B and C were decreased by 28 % and 37 % (both P < 0.001), respectively. Conclusion Compared with 80 kVp protocol, 70 kVp brain CTP allows comparable vascular and perfusion assessment and lower radiation dose while maintaining high diagnostic accuracy in detecting acute infarct. Key Points • 70 kVp whole brain CTP can provide diagnostic image quality . • 70 kVp CTP diagnostic accuracy was maintained vs. 80 kVp protocol . • 70 kVp CTP radiation doses were lower than 80 kVp protocol .

To evaluate the impact of an advanced monoenergetic (ME) reconstruction algorithm on CT coronary stent imaging in a phantom model.

Objectives: To compare image quality and diagnostic accuracy for the detection of liver lesions of virtual unenhanced (VU) images based on third-generation dual-source dual- energy computed tomography (DECT) compared to conventional unenhanced (CU) images.Methods: Thirty patients underwent triphasic abdominal CT consisting of single-energy CU (120 kV, 147 ref.mAs) and dual-energy CT arterial and portal-venous phase acquisitions (100/Sn150 kV, 180/90 ref.mAs). VU images were generated from arterial (AVU) and portal venous (PVU) phases. CU, AVU and PVU datasets were reconstructed. Quantitative image quality analysis was performed and two abdominal radiologists independently analyzed all datasets to evaluate image quality and identify liver lesions. Radiation dose was recorded and potential radiation dose reduction was estimated.Results: Image quality was rated diagnostic in 100% of the VU datasets. The mean subjective image quality of the CU datasets was higher than that of VU images (p < 0.0001). No significant difference was observed in the mean attenuation values of the liver parenchyma (p > 0.99) and hypoattenuating liver lesions (p >= 0.21) between CU, AVU and PVU. However, a significant reduction in the attenuation values of calcified lesions (p < 0.0001), metallic clips (p < 0.0001) and gallstones (p <= 0.047) was observed in the AVU and PVU images compared with CU images. A total of 122 liver lesions were found in 25 patients. VU images were more sensitive than CU images for detection of small hypoattenuating liver lesions (<= 1 cm). However, CU images were more sensitive than VU for calcified liver lesions. The mean radiation dose reduction achievable by avoiding the unenhanced acquisition was 32.9% +/- 1.1% (p < 0.01).Conclusions: Third-generation DSCT VU images of the liver provide diagnostic image quality and improve small (<= 1 cm) liver lesion detection; however calcified liver lesions can be missed due to complete subtraction. (C) 2016 Elsevier Ireland Ltd. All rights reserved.

Objective The aim of this study was to evaluate the impact of a noise-optimized virtual monochromatic imaging algorithm (VMI+) on image quality and diagnostic accuracy at dual-energy computed tomography angiography (CTA) of the lower extremity runoff. Materials and Methods This retrospective Health Insurance Portability and Accountability Act–compliant study was approved by the local institutional review board. We evaluated dual-energy CTA studies of the lower extremity runoff in 48 patients (16 women; mean age, 63.3 ± 13.8 years) performed on a third-generation dual-source CT system. Images were reconstructed with standard linear blending (F_0.5), VMI+, and traditional monochromatic (VMI) algorithms at 40 to 120 keV in 10-keV intervals. Vascular attenuation and image noise in 18 artery segments were measured; signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated. Five-point scales were used to subjectively evaluate vascular attenuation and image noise. In a subgroup of 21 patients who underwent additional invasive catheter angiography, diagnostic accuracy for the detection of significant stenosis (≥50% lumen restriction) of F_0.5, 50-keV VMI+, and 60-keV VMI data sets were assessed. Results Objective image quality metrics were highest in the 40- and 50-keV VMI+ series (SNR: 20.2 ± 10.7 and 19.0 ± 9.5, respectively; CNR: 18.5 ± 10.3 and 16.8 ± 9.1, respectively) and were significantly (all P < 0.001) higher than in the corresponding VMI data sets (SNR: 8.7 ± 4.1 and 10.8 ± 5.0; CNR: 8.0 ± 4.0 and 9.6 ± 4.9) and F_0.5 series (SNR: 10.7 ± 4.4; CNR: 8.3 ± 4.1). Subjective assessment of attenuation was highest in the 40- and 50-keV VMI and VMI+ image series (range, 4.84–4.91), superior to F_0.5 (4.07; P < 0.001). Corresponding subjective noise assessment was superior for 50-keV VMI+ (4.71; all P < 0.001) compared with VMI (2.60) and F_0.5 (4.11). Sensitivity and specificity for detection of 50% or greater stenoses were highest in VMI+ reconstructions (92% and 95%, respectively), significantly higher compared with standard F_0.5 (87% and 90%; both P ≤ 0.02). Conclusions Image reconstruction using low-kiloelectron volt VMI+ improves image quality and diagnostic accuracy compared with traditional VMI technique and standard linear blending for evaluation of the lower extremity runoff using dual-energy CTA.

Purpose To compare, on an intra-individual basis, the effect of automated tube voltage selection (ATVS), integrated circuit detector and advanced iterative reconstruction on radiation dose and image quality of aortic CTA studies using 2nd and 3rd generation dual-source CT (DSCT). Material and methods We retrospectively evaluated 32 patients who had undergone CTA of the entire aorta with both 2nd generation DSCT at 120 kV using filtered back projection (FBP) (protocol 1) and 3rd generation DSCT using ATVS, an integrated circuit detector and advanced iterative reconstruction (protocol 2). Contrast-to-noise ratio (CNR) was calculated. Image quality was subjectively evaluated using a five-point scale. Radiation dose parameters were recorded. Results All studies were considered of diagnostic image quality. CNR was significantly higher with protocol 2 (15.0 ± 5.2 vs 11.0 ± 4.2; p < .0001). Subjective image quality analysis revealed no significant differences for evaluation of attenuation (p= 0.08501) but image noise was rated significantly lower with protocol 2 (p= 0.0005). Mean tube voltage and effective dose were 94.7 ± 14.1 kV and 6.7 ± 3.9 mSv with protocol 2; 120 ± 0 kV and 11.5 ± 5.2 mSv with protocol 1 (p< 0.0001, respectively). Conclusion Aortic CTA performed with 3rd generation DSCT, ATVS, integrated circuit detector, and advanced iterative reconstruction allow a substantial reduction of radiation exposure while improving image quality in comparison to 120 kV imaging with FBP.

Rationale and Objectives: Iterative reconstruction (IR) computed tomography (CT) techniques allow for radiation dose reduction while maintaining image quality. However, CT coronary artery calcium (CAC) scores may be influenced by certain IR algorithms. The aim of our study is to identify suitable correction factors to ensure consistency between IR and filtered back projection (FBP)-based CAC scoring.Material and Methods: A phantom study was performed to derive suitable correction factors for CAC scores and volume (VOL) values with advanced modeled iterative reconstruction (or ADMIRE) strength level 3 (ADM3) and 5 (ADM5) vs FBP. CT data from 40 patients were retrospectively analyzed, and CAC score and VOL values were obtained following reconstruction with FBP, ADM3, and ADM5. Linear regression analysis was performed to obtain correction factors. Results with and without application of the correction factors were compared. Inter-reader agreement for risk class stratification was analyzed.Results: Phantom experiments determined a correction factor of 1.14 for ADM3 and 1.25 for ADM5. FBP-based CAC scores (897 +/- 1413) were significantly higher than uncorrected scores with ADM3 (746 +/- 1184, P.001) and ADM5 (640 +/- 1036, P <=.001). After application of correction factors, no significant differences were found for CAC scores based on FBP (897 +/- 1413) and ADM3 (853 +/- 1353, P =.07). The inter-reader agreement for risk stratification was excellent (k = 0.91).Conclusion: ADM3 can be applied to CAC scoring with use of a correction factor. When applying a correction factor of 1.14, excellent agreement with standard FBP for both CAC score and VOL can be achieved.

Myocardial infarct (MI) size has been increasingly used as an endpoint in multiple clinical trials and has thus become an important clinical measure. While late gadolinium enhancement MRI is considered the clinical reference standard to detect, characterize, and quantify MI, there is no established universal quantification algorithm that provides reliable MI assessment in every scenario. Efforts have been made to improve the binary threshold-based methods which dichotomize MRI voxels as either healthy or infarcted. Novel algorithms have also been proposed to quantify the actual infarcted tissue content of each MRI voxel while accounting for partial volume averaging, a common issue in quantitative MRI. Currently, the full-width at half-maximum binary algorithm seems to have the highest accuracy and reproducibility. Non-binary algorithms show comparable results; however, the literature is limited in terms of their clinical feasibility.

Background Conventional inversion recovery (IR) techniques for the detection of late gadolinium enhancement (LGE) in the myocardium are bright blood methods in which the signal in the blood chamber is often similar to the signal in hyperenhanced irreversibly damaged myocardial areas. Due to the low contrast to noise ratio (CNR) between blood and the hyperenhanced myocardium at the tissue-blood interface, the discrimination of subendocardial LGE from blood is often challenging with this approach. The aim of our study was to evaluate the accuracy of a prototype dark blood LGE technique for the detection and quantification of myocardial LGE in patients with myocardial infarction (MI) when compared to conventional IR LGE technique.

Purpose: To determine the optimal timing of arterial first pass computed tomography (CT) myocardial perfusion imaging (CTMPI) based on dynamic CTMPI acquisitions.Methods and materials: Twenty-five patients (59 + 8.4 years, 14 male)underwent adenosine-stress dynamic CTMPI on second-generation dual-source CT in shuttle mode (30 s at 100 kV and 300 mAs). Stress perfusion magnetic resonance imaging (MRI) was used as reference standard for differentiation of non-ischemic and ischemic segments. The left ventricle (LV) wall was manually segmented according to the AHA 16-segment model. Hounsfield units (HU) in myocardial segments and ascending (AA) and descending aorta (AD) were monitored over time. Time difference between peak AA and peak AD and peak myocardial enhancement was calculated, as well as the, time delay from fixed HU thresholds of 150 and 250 HU in the AA and AD to a minimal difference of 15 HU between normal and ischemic segments. Furthermore, the duration of the 15 HU difference between ischemic and non-ischemic segments was calculated.Results: Myocardial ischemia was observed by MRI in 10 patients (56.3 +/- 9.0 years; 8 male). The delay between the maximum HU in the AA and AD and maximal HU in the non-ischemic segments was 2.8 s [2.2-4.3] and 0.0 s [0.0-2.8], respectively. Differentiation between ischemic and non-ischemic myocardial segments in CT was best during a time window of 8.6 +/- 3.8 s. Time delays for AA triggering were 4.5 s [2.2-5.6] and 2.2 s [0-2.8] for the 150 HU and 250 HU thresholds, respectively. While for AD triggering, time delays were 2.4 s [0.0-4.8] and 0.0 s [-2.2-2.6] for the 150 HU and 250 HU thresholds, respectively.Conclusion: In CTMPI, the differentiation between normal and ischemic myocardium is best accomplished during a time interval of 8.6 + 3.8 s. This time window can be utilized by a test bolus or bolus tracking in the AA or AD using the time delays identified here. (C) 2016 Elsevier Ireland Ltd. All rights reserved.