Highly efficient head-only magnetic field insert gradient coil for achieving simultaneous high gradient amplitude and slew rate at 3.0T (MAGNUS) for brain microstructure imaging.

PURPOSE: To develop a highly efficient magnetic field gradient coil for head imaging that achieves 200 mT/m and 500 T/m/s on each axis using a standard 1 MVA gradient driver in clinical whole-body 3.0T MR magnet. METHODS: A 42-cm inner diameter head-gradient used the available 89- to 91-cm warm bore space in a whole-body 3.0T magnet by increasing the radial separation between the primary and the shield coil windings to 18.6 cm. This required the removal of the standard whole-body gradient and radiofrequency coils. To achieve a coil efficiency ~4× that of whole-body gradients, a double-layer primary coil design with asymmetric x-y axes, and symmetric z-axis was used. The use of all-hollow conductor with direct fluid cooling of the gradient coil enabled ≥50 kW of total heat dissipation. RESULTS: This design achieved a coil efficiency of 0.32 mT/m/A, allowing 200 mT/m and 500 T/m/s for a 620 A/1500 V driver. The gradient coil yielded substantially reduced echo spacing, and minimum repetition time and echo time. In high b = 10,000 s/mm2 diffusion, echo time (TE) < 50 ms was achieved (>50% reduction compared with whole-body gradients). The gradient coil passed the American College of Radiology tests for gradient linearity and distortion, and met acoustic requirements for nonsignificant risk operation. CONCLUSIONS: Ultra-high gradient coil performance was achieved for head imaging without substantial increases in gradient driver power in a whole-body 3.0T magnet after removing the standard gradient coil. As such, any clinical whole-body 3.0T MR system could be upgraded with 3-4× improvement in gradient performance for brain imaging.

Lightweight, compact, and high-performance 3T MR system for imaging the brain and extremities.

PURPOSE: To build and evaluate a small-footprint, lightweight, high-performance 3T MRI scanner for advanced brain imaging with image quality that is equal to or better than conventional whole-body clinical 3T MRI scanners, while achieving substantial reductions in installation costs. METHODS: A conduction-cooled magnet was developed that uses less than 12 liters of liquid helium in a gas-charged sealed system, and standard NbTi wire, and weighs approximately 2000 kg. A 42-cm inner-diameter gradient coil with asymmetric transverse axes was developed to provide patient access for head and extremity exams, while minimizing magnet-gradient interactions that adversely affect image quality. The gradient coil was designed to achieve simultaneous operation of 80-mT/m peak gradient amplitude at a slew rate of 700 T/m/s on each gradient axis using readily available 1-MVA gradient drivers. RESULTS: In a comparison of anatomical imaging in 16 patients using T2 -weighted 3D fluid-attenuated inversion recovery (FLAIR) between the compact 3T and whole-body 3T, image quality was assessed as equivalent to or better across several metrics. The ability to fully use a high slew rate of 700 T/m/s simultaneously with 80-mT/m maximum gradient amplitude resulted in improvements in image quality across EPI, DWI, and anatomical imaging of the brain. CONCLUSIONS: The compact 3T MRI system has been in continuous operation at the Mayo Clinic since March 2016. To date, over 200 patient studies have been completed, including 96 comparison studies with a clinical 3T whole-body MRI. The increased gradient performance has reliably resulted in consistently improved image quality.

Interactions between risky decisions, impulsiveness and smoking in young tattooed women.

BACKGROUND: According to previous studies, one of the common problems of everyday life of persons with tattoos is risky behavior. However, direct examination of the decision making process, as well as factors which determine women's risk-taking decisions to get tattoos, have not been conducted. This study investigates whether risk taking decision-making is associated with the self-assessment impulsiveness in tattooed women. METHODS: Young women (aged 18-35 years) with (N = 60) and without (N = 60) tattoos, performed the Iowa Gambling Task (IGT), as a measure of decision-making processes, as well as completing the Barratt Impulsivity Scale (BIS-11). RESULTS: Tattooed women showed significantly higher scores in the BIS-11 and preference for disadvantageous decks on the IGT compared to non-tattooed women. There was no significant correlation between risky decision-making in the IGT and BIS-11 impulsivity measures. A significantly higher rate of smoking was observed in the tattooed women. However, the analysis did not reveal a group effect after adjustment for smoking in the IGT and the BIS-11 measures. CONCLUSIONS: The present study was specifically designed to resolve questions regarding associations between impulsiveness and risky decision-making in tattooed women. It shows that in tattooed women, risky decisions are not a direct result of their self-reported impulsiveness. Smoking does not explain the psychometric differences between tattooed women and controls.

The use of a fully integrated electronic medical record to minimize cumulative lifetime radiation exposure from CT scanning to detect urinary tract calculi.

In order to determine the effects of implementation of an electronic medical record on rates of repeat computed tomography (CT) scanning in the emergency department (ED) setting, we analyzed the utilization of CT of the kidneys, ureters, and bladder (CT KUB) for the detection of urinary tract calculi for periods before and after the implementation of a hospital-wide electronic medical record system. Rates of repeat CT scanning within a 6-month period of previous scan were determined pre- and post-implementation and compared. Prior to implementation, there was a 6-month repeat rate of 6.2 % compared with the post-implementation period, which was associated with a 6-month repeat rate of 4.1 %. Statistical analysis using a two-sample, one-tailed t test for difference of means was associated with a p value of 0.00007. This indicates that the implementation of the electronic medical record system was associated with a 34 % decrease in 6-month repeat CT KUB scans. We conclude that the use of an electronic medical record can be associated with a decrease in utilization of unnecessary repeat CT imaging, leading to decreased cumulative lifetime risk for cancer in these patients and more efficient utilization of ED and radiologic resources.

Relationship between smoking, narcissism, and impulsiveness among young women.

Although the connection between smoking and individual differences has been recently recognized, the relationship between narcissistic personality traits and cigarette smoking has received less attention. The notion that personality traits can be associated with addictive behavior is influential in clinical practice. However, questions remain about specific interactions between smoking and personality characteristics that need empirical support to substantiate this hypothesis. This study thus identifies narcissistic and impulsive personality traits as precursors of smoking in a sample of tattooed individuals. In a cross-sectional study (N = 120), personality traits were assessed in young women (aged 18-35 years) using the narcissistic personality inventory and the Barratt Impulsivity Scale (BIS-11). The current study, using the regression analysis, has clearly demonstrated that young women who smoke have different personality characteristics as compared with women who do not smoke.

The role of inhibition capacities in the Iowa gambling test performance in young tattooed women.

BACKGROUND: Using the Iowa Gambling Test (IGT), we demonstrated previously impaired decision- making process in young tattooed women. The purpose of the present study was to explore the associations among the three facets of impaired inhibition (response inhibition, reflection inhibition and interference inhibition) and decision-making processes in this population. METHODS: To this end, the participants of the previous study (60 tattooed women and 60 non-tattooed women) were assessed in the Go/NoGo task, a measure of response inhibition, the Matched Familiar Figure Test (MFFT), a measure of reflection inhibition and the Stroop task a measure of interference inhibition. RESULTS: Tattooed women were significantly slower than non-tattooed women in the Go/NoGo performance; however, no differences were detected in the MFFT and the Stroop task. A hierarchical regression analysis did not reveal any significant main effects of these inhibition measures on the IGT performance. CONCLUSIONS: These findings do not support the hypothesis that risky decision in young tattooed women is due to impaired inhibitory control. Further studies are needed to identify the cognitive mechanisms involved in the tendency to risky decisions in young tattooed women.

Do young women with tattoos have lower self-esteem and body image than their peers without tattoos? A non-verbal repertory grid technique approach.

Available evidence regarding the reasons for people to acquire body markers such as tattoos is contradictory. The present study was designed to investigate the relationship between self-esteem and body image in young women with tattoos. To this end, the repertory grid technique (RGT) was adapted and used to assess differences between women with and without tattoos in terms of self-esteem and body image. Sixty young women with tattoos and sixty young women without (all aged 18-35 years), performed the Color RGT in order to evaluate the relationship between self-esteem and body image. Compared to women without tattoos, women with tattoos showed significantly lower self-esteem and displayed stronger relationships between three constructs: ideal body, ideal self and tattooed woman status. No significant differences in body image were detected between the two groups. Women with tattoos were characterized by an association between body image and self-esteem, while women without tattoos did not display such a correlation. Thus, it appears that links between self-esteem, ideal body, ideal self and constructs of "woman with tattoos" may play a role in tattooing behavior in young women.