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Brain tissue undergoes viscoelastic deformation and volumetric strain as it expands over the cardiac cycle due to blood volume changes within the underlying microvasculature. Volumetric strain measurements may therefore provide insights into small vessel function and tissue viscoelastic properties. Displacement encoding via stimulated echoes (DENSE) is an MRI technique that can quantify the submillimetre displacements associated with brain tissue motion. Despite previous studies reporting brain tissue displacements using DENSE and other MRI techniques, a complete picture of brain tissue volumetric strain over the cardiac cycle has not yet been obtained. To address this need we implemented 3D cine-DENSE at 7 T and 3 T to investigate the feasibility of measuring cardiac-induced volumetric strain as a marker for small vessel blood volume changes. Volumetric strain over the entire cardiac cycle was computed for the whole brain and for grey and white matter tissue separately in six healthy human subjects. Signal-to-noise ratio (SNR) measurements were used to determine the voxel-wise volumetric strain noise. Mean peak whole brain volumetric strain at 7 T (mean ± SD) was (4.5 ± 1.0) × 10 -4 (corresponding to a volume expansion of 0.48 ± 0.1 mL), which is in agreement with literature values for cerebrospinal fluid that is displaced into the spinal canal to maintain a stable intracranial pressure. The peak volumetric strain ratio of grey to white matter was 4.4 ± 2.8, reflecting blood volume and tissue stiffness differences between these tissue types. The mean peak volumetric strains of grey and white matter tissue were found to be significantly different (p < 0.001). The mean SNR at 7 T and 3 T of the DENSE measurements was 22.0 ± 7.3 and 7.0 ± 2.8 respectively, which currently limits a voxel-wise strain analysis at both field strengths. We demonstrate that tissue specific quantification of volumetric strain is feasible with DENSE. This metric holds potential for studying blood volume pulsations in the ageing brain in healthy and diseased states., (© 2018 The Authors. NMR in Biomedicine published by John Wiley & Sons Ltd.)

The use of neoadjuvant chemotherapy prior to surgical resection for breast cancer is no longer restricted to patients with locally advanced disease. As preoperative treatment becomes more common, the question arises whether or not such therapy changes important tumor characteristics. The objective of our study is to compare histological grade, hormone receptor status, and HER2/neu expression pre- and post-therapy patients receiving preoperative neo-adjuvant chemotherapy. Forty patients status post-neoadjuvant treatment who had available archived pathologic material pre- and post-therapy were identified. Glass slides were reviewed retrospectively, and tumor grade, hormone receptor status, and HER2/neu expression were compared between the pre- and post-therapy specimens. No significant differences were noted between the pre- and post-specimens for two of the three parameters comprising the modified Bloom-Richardson grade, including degree of tubule formation (p = 0.062) and nuclear pleomorphism (p = 0.086). For mitotic activity, a decrease in score was observed between pre- and post-therapy specimens which was statistically significant (p = 0.021). However, there was no significant difference in the overall modified Bloom-Richardson grade (p = 0.118). Information was available regarding hormone receptor and HER2/neu status in 26 patients (65%). There was no significant difference between pre- and post-treatment specimens for hormone receptor status. However, there were more patients with HER2/neu overexpression after receiving neoadjuvant therapy (p = 0.027). Neoadjuvant therapy resulted in a significant decrease in mitotic count and an increase in the proportion of patients with HER2/neu overexpression. No significant changes were noted for the degree of tubule formation, nuclear pleomorphism, overall Bloom-Richardson score, and hormone receptor status. However, small sample size may be a limitation of these results.

Objectives: Soccer, an increasingly popular sport among children in the United States, is a common precipitant to injury-related emergency department (ED) visits. The authors estimated the number of children treated in EDs for soccer-related injuries and described the nature of these injuries., Methods: Data from the 2000 National Electronic Injury Surveillance System All Injury Program were used to estimate the overall number and rate of soccer injuries in children, calculate injury rates per 1,000 children, and describe the body regions affected and types of injuries. Results were stratified by five-year age groups (5-9 years, 10-14 years, and 15-19 years)., Results: Approximately 144,600 children sustained soccer-related injuries in 2000 for a rate of 2.36 injuries per 1,000 children. Injury rates increased with age (0.8, 5-9 year olds; 3.1, 10-14 year olds; 3.2, 15-19 year olds). Common types of injuries were strains/sprains (36.7%), fractures (23.0%), and contusions (20.9%). Fractures decreased with age; sprains/strains increased with age. Commonly injured body regions varied by age. Wrist and finger injuries were most common (12.7% and 12.4%, respectively) in the youngest group; in the 10-14-year-old group, ankle and wrist injuries were most common (15.7% and 13.6%, respectively). In the oldest age group, ankle injuries were most common (21.9%), followed by knee injuries (17.6%)., Conclusions: Substantial numbers of children were treated in EDs for soccer-related injuries. Injury types and affected body regions varied by age. Injury prevention efforts to reduce soccer-related injuries may need to be age specific.

Objectives: To test a hypothesis that patients would accept alternatives to transport to an emergency department (ED) by ambulance and to evaluate factors related to patient willingness to consider alternatives. Concerns about resource utilization have prompted emergency medical services (EMS) systems to explore alternatives to ambulance transport to an ED, but studies have evaluated the safety of alternatives, not patient preferences., Methods: Trained research assistants surveyed patients transported by ambulance to a university ED. Interfacility transfers, trauma patients, and critically ill patients were excluded. The primary outcome was willingness to accept one of several presented alternatives to ambulance transport to the ED for that visit. Demographic and clinical factors were evaluated for association with willingness to consider alternatives. Relative risks (RR) and 95% confidence intervals (95% CI) were determined by using Mantel-Haenszel stratified methods., Results: Three hundred fifteen subjects completed the survey. Two hundred forty-seven (78.4%) were willing to consider at least one alternative. One hundred ninety-four (61.6%) were willing to consider transportation by car, and 177 (56.2%) were willing to consider transportation by taxi. Factors associated with willingness to consider alternatives included the following: age 18-65 years (RR, 1.25; 95% CI = 1.03 to 1.49), being unemployed (RR, 1.08; 95% CI = 1.08 to 1.33), use of the ED for routine care (RR, 1.25; 95% CI = 1.17 to 1.35), and not being admitted to the hospital (RR, 1.19; 95% CI = 1.04 to 1.40). Race, gender, health insurance status, and EMS interventions en route were not associated with willingness to consider transportation alternatives., Conclusions: Many patients transported by ambulance to an ED would have considered an alternative, if one were offered.

Objective: To determine whether computer-assisted prescription writing reduces the frequency of prescription errors in the emergency department (ED)., Methods: A pre-post retrospective analysis was used to compare errors between handwritten (HW) and computer-assisted (CA) ED prescriptions. Prescriptions were reviewed for pharmacist clarifications. A clarification was defined as an error if missing information, incorrect information, incorrect dose, non-formulary medication, or illegibility was the reason for clarification. The HW and CA error rates were compared using odds ratios (ORs) with 95% confidence intervals (95% CIs)., Results: During the pre-intervention period, there were 7,036 patient visits with 2,326 HW ED prescriptions filled for 1,459 patients. There were 91 clarifications, with a rate of 3.9%. There were 54 HW errors, for an error rate of 2.3%. During the post-intervention period, there were 7,845 patient visits with 1,594 CA prescriptions filled for 1,056 patients. There were 13 clarifications, with a clarification rate of 0.8%, and 11 errors, for a CA error rate of 0.7%. The CA prescriptions were substantially less likely to contain an error [OR 0.31 (95% CI = 0.10 to 0.36)] or to require pharmacist clarification [OR 0.19 (95% CI = 0.10 to 0.36)] than were the HW prescriptions., Conclusions: Computer-assisted prescriptions were more than three times less likely to contain errors and five times less likely to require pharmacist clarification than handwritten prescriptions.

On clot-promoting surfaces, intact normal blood or plasma deposits fibrinogen and then supplants it with high molecular weight kininogen (HMWK). On glass, plasma layers of less than about 25 micron thick, while still containing enough fibrinogen to coat the surrounding surfaces, lack sufficient HMWK per surface area to remove this fibrinogen deposit. Thus normal intact citrated plasma allowed to enter the space between a glass slide and a convex lens resting belly-down on the slide will leave a disc of fibrinogen where the thickness of plasma layer was below this "critical height" H. The discs of fibrinogen left by plasma that lacks HMWK pathologically or by activation or dilution, are larger--the required H being greater. The present study shows that plasma dilution (final volume divided by original plasma volume) plotted against H yields a straight line. In preliminary series, the slope of this line increases with the atomic weight of five metals whose oxidized surfaces were used as substrates. In whole blood collected in either heparin or ACD, a circle of platelets adheres to oxidized silicon, anodized tantalum, or glass; this circle is similar in size to the one of fibrinogen left by plasma.