Advanced Diffusion-Weighted Imaging Sequences for Breast MRI: Comprehensive Comparison of Improved Sequences and Ultra-High B-Values to Identify the Optimal Combination

This study investigated the image quality and choice of ultra-high b-value of two DWI breast-MRI research applications. The study cohort comprised 40 patients (20 malignant lesions). In addition to s-DWI with two m-b-values (b50 and b800) and three e-b-values (e-b1500, e-b2000, and e-b2500), z-DWI and IR m-b1500 DWI were applied. z-DWI was acquired with the same measured b-values and e-b-values as the standard sequence. For IR m-b1500 DWI, b50 and b1500 were measured, and e-b2000 and e-b2500 were mathematically extrapolated. Three readers used Likert scales to independently analyze all ultra-high b-values (b1500-b2500) for each DWI with regards to scan preference and image quality. ADC values were measured in all 20 lesions. z-DWI was the most preferred (54%), followed by IR m-b1500 DWI (46%). b1500 was significantly preferred over b2000 for z-DWI and IR m-b1500 DWI (p = 0.001 and p = 0.002, respectively). Lesion detection was not significantly different among sequences or b-values (p = 0.174). There were no significant differences in measured ADC values within lesions between s-DWI (ADC: 0.97 [±0.09] × 10$^{-3}$ mm$^{2}$/s) and z-DWI (ADC: 0.99 [±0.11] × 10$^{-3}$ mm$^{2}$/s; p = 1.000). However, there was a trend toward lower values in IR m-b1500 DWI (ADC: 0.80 [±0.06] × 10$^{-3}$ mm$^{2}$/s) than in s-DWI (p = 0.090) and z-DWI (p = 0.110). Overall, image quality was superior and there were fewer image artifacts when using the advanced sequences (z-DWI + IR m-b1500 DWI) compared with s-DWI. Considering scan preferences, we found that the optimal combination was z-DWI with a calculated b1500, especially regarding examination time

Initial Experience of Applying TWIST Dixon with Flexible View Sharing in Breast DCE-MRI

Introduction We developed a new fast imaging technique with flexible time-resolved angiography with stochastic trajectories (TWIST) view sharing to achieve variable temporal resolution and with flexible echo time Dixon to achieve robust fat suppression and to evaluate its application in breast dynamic contrast enhanced-magnetic resonance imaging (DCE-MRI). Materials and Methods The TWIST-Dixon technique was improved with more flexible view sharing and echo times (TWIST-Dixon-Flex). In a dynamic series, each measurement can be separately prescribed as “full,” “partial,” or “center-only.” The spatial and temporal resolution can then be adjusted throughout the measurements to match the dynamic characteristics of contrast enhancement at different phases. The potential advantages of TWIST-Dixon-Flex were evaluated with 18 clinical breast DCE MRI cases. A mixed-effects analysis of variance (ANOVA) was performed to compare the image quality with that of the conventional images. Results The ANOVA showed that the quality of postcontrast TWIST-Dixon-Flex images was significantly higher than that of the conventional images. The TWIST-Dixon-Flex technique also provided the capability to detect differences in rapid contrast uptake from different regions of the breast tumor, which is not possible with conventional breast DCE-MRI. Conclusion The new TWIST-Dixon-Flex technique provides potentially valuable information about early tumor enhancement, and maintains excellent image quality at peak and postcontrast enhancement. This technique could help overcome the compromise on spatial over temporal resolution in clinical breast imaging

Latitude, Birth Date, and Allergy

BACKGROUND: The space and time distribution of risk factors for allergic diseases may provide insights into disease mechanisms. Allergy is believed to vary by month of birth, but multinational studies taking into account latitude have not been conducted. METHODS AND FINDINGS: A questionnaire was distributed in 54 centres to a representative sample of 20- to 44-y-old men and women mainly in Europe but also including regions in North Africa, India, North America, Australia, and New Zealand. Data from 200,682 participants were analyzed. The median prevalence of allergic rhinitis was 22%, with a substantial variation across centres. Overall, allergic rhinitis decreased with geographical latitude, but there were many exceptions. No increase in prevalence during certain winters could be observed. Also, no altered risk by birth month was found, except borderline reduced risks in September and October. Effect estimates obtained by a multivariate analysis of total and specific IgE values in 18,085 individuals also excluded major birth month effects and confirmed the independent effect of language grouping. CONCLUSION: Neither time point of first exposure to certain allergens nor early infections during winter months seems to be a major factor for adult allergy. Although there might be effects of climate or environmental UV exposure by latitude, influences within language groups seem to be more important, reflecting so far unknown genetic or cultural risk factors

Automatische Quantifizierung von Metabolitenkonzentrationen in :i:in vivo:/i: Spektren

:p:A number of dedicated quantification tools have been developed for the interpretation of :i:in vivo:/i: magnetic resonance spectroscopy (MRS) data. To be useful in a clinical setting these tools have to meet the requirements of both a high level of automation and a general applicability in a wide range of clinical examinations. Existing tools put their main emphasis on one or other of these two aspects, but not on both simultaneously. The quantification tool of this work, PRISMA, was therefore developed to meet both of these requirements and to deliver reproducible and consistent results with good reliability. :p:The design of PRISMA allows on the one hand an easy adaptation to different applications due to a very flexible model parameterization. On the other hand it guaranties a robust and automatic result generation by an assumption-free assignment of the metabolites. For the baseline a new model is introduced which is based on a finite time signal. :p:The robust behavior of the PRISMA quantification is demonstrated on diverse :sup:1:/sup:H MRS data acquired from different anatomical regions. Besides synthetic data signals from brain and prostate measurements of healthy and pathological tissue were analyzed. The measurements were done at varying field strength, echo times and signal to noise ratios using single voxel and multi voxel techniques (SVS, SI). In addition, typical characteristics of PRISMA such as reproducibility and reliability were investigated and found to compare well with the performance of other quantification tools

Automatic Quantification of Metabolite Concentrations in :i:in vivo:/i: Spectra

:p:A number of dedicated quantification tools have been developed for the interpretation of :i:in vivo:/i: magnetic resonance spectroscopy (MRS) data. To be useful in a clinical setting these tools have to meet the requirements of both a high level of automation and a general applicability in a wide range of clinical examinations. Existing tools put their main emphasis on one or other of these two aspects, but not on both simultaneously. The quantification tool of this work, PRISMA, was therefore developed to meet both of these requirements and to deliver reproducible and consistent results with good reliability. :p:The design of PRISMA allows on the one hand an easy adaptation to different applications due to a very flexible model parameterization. On the other hand it guaranties a robust and automatic result generation by an assumption-free assignment of the metabolites. For the baseline a new model is introduced which is based on a finite time signal. :p:The robust behavior of the PRISMA quantification is demonstrated on diverse :sup:1:/sup:H MRS data acquired from different anatomical regions. Besides synthetic data signals from brain and prostate measurements of healthy and pathological tissue were analyzed. The measurements were done at varying field strength, echo times and signal to noise ratios using single voxel and multi voxel techniques (SVS, SI). In addition, typical characteristics of PRISMA such as reproducibility and reliability were investigated and found to compare well with the performance of other quantification tools

Rétification du bois de pin maritime : impact sur la structure des lignines en relation avec les performances du bois matériau.

National audienceLa rétification du bois (traitement thermique sous atmosphère inerte entre 200 et 260°C) augmente la stabilité dimensionnelle et la résistance aux attaques fongiques de ce matériau. La compréhension des modifications de ces propriétés macroscopiques à l'échelle moléculaire est un préalable à l'utilisation raisonnée de la rétification. Dans ce but, les modifications induites au sein des lignines de bois de pin maritime ont été étudiées en relation avec les conditions expérimentales de la rétification et les performances du bois matériau. Si ces altérations sont très modérées jusqu'à 230°C, des modifications structurales importantes des lignines de pin surviennent lors du traitement du bois 5 minutes à 240°C, sous atmosphère inertes. Ces conditions correspondent précisément aux conditions de rétification permettant d'augmenter significativement la stabilité dimensionnelle et la résistance aux attaques fongiques du bois de pin sans altérer ses propriétés mécaniques de manière rédhibitoire. Au-delà de ce seuil expérimental, dans des conditions de thermolyse plus poussées (5 minutes à 250°C ou 45 minutes à 240°C), la structure des lignines évolue de manière moins accentuée tandis que les propriétés mécaniques du bois matériau s'effondrent

A Serious Game for the Prevention of Obesity in School Children–Impact of Parent’s Involvement: A Randomized Controlled Trial

Serious games convey information and use interactive components to reinforce and train behaviours. A serious game addressing nutrition, physical activity and stress coping—the Kids Obesity Prevention Program (KOP)—was previously evaluated for efficacy in children. This study aimed at evaluating the KOP-game regarding: (i) its acceptance and efficacy with respect to parents of primary school children receiving the same game intervention as the children; and (ii) whether the children could benefit by parental involvement. A randomized controlled trial with two groups of children aged 9 to 12 years was conducted which included a 6-month follow-up period. All children played the game twice in two weeks. In the family-intervention group, the parents additionally played the game. The primary outcome was the gain in knowledge in parents and children measured with a pretested questionnaire. The secondary outcomes were knowledge maintenance as well as several behavior changes. Parents and children in both groups improved and maintained their knowledge equally. The KOP-game increases knowledge of nutrition in children independently of the involvement of their parents. KOP games are well accepted in children; further research should examine the structured involvement of parents

Thin-Slice Prostate MRI Enabled by Deep Learning Image Reconstruction

Objectives: Thin-slice prostate MRI might be beneficial for prostate cancer diagnostics. However, prolongation of acquisition time is a major drawback of thin-slice imaging. Therefore, the purpose of this study was to investigate the impact of a thin-slice deep learning accelerated T2-weighted (w) TSE imaging sequence (T2DLR) of the prostate as compared to conventional T2w TSE imaging (T2S). Materials and Methods: Thirty patients were included in this prospective study at one university center after obtaining written informed consent. T2S (3 mm slice thickness) was acquired first in three orthogonal planes followed by thin-slice T2DLR (2 mm slice thickness) in axial plane. Acquisition time of axial conventional T2S was 4:12 min compared to 4:37 min for T2DLR. Imaging datasets were evaluated by two radiologists using a Likert-scale ranging from 1–4, with 4 being the best regarding the following parameters: sharpness, lesion detectability, artifacts, overall image quality, and diagnostic confidence. Furthermore, preference of T2S versus T2DLR was evaluated. Results: The mean patient age was 68 ± 8 years. Sharpness of images and lesion detectability were rated better in T2DLR with a median of 4 versus a median of 3 in T2S (p DLR as compared to T2S (p p = 0.021, respectively). Overall image quality was also evaluated to be superior in T2DLR versus T2S with a median of 4 versus 3 (p DLR in 29 cases as their preference. Conclusions: Thin-slice T2DLR of the prostate provides a significant improvement of image quality without significant prolongation of acquisition time

Advanced Diffusion-Weighted Imaging Sequences for Breast MRI: Comprehensive Comparison of Improved Sequences and Ultra-High B-Values to Identify the Optimal Combination

This study investigated the image quality and choice of ultra-high b-value of two DWI breast-MRI research applications. The study cohort comprised 40 patients (20 malignant lesions). In addition to s-DWI with two m-b-values (b50 and b800) and three e-b-values (e-b1500, e-b2000, and e-b2500), z-DWI and IR m-b1500 DWI were applied. z-DWI was acquired with the same measured b-values and e-b-values as the standard sequence. For IR m-b1500 DWI, b50 and b1500 were measured, and e-b2000 and e-b2500 were mathematically extrapolated. Three readers used Likert scales to independently analyze all ultra-high b-values (b1500–b2500) for each DWI with regards to scan preference and image quality. ADC values were measured in all 20 lesions. z-DWI was the most preferred (54%), followed by IR m-b1500 DWI (46%). b1500 was significantly preferred over b2000 for z-DWI and IR m-b1500 DWI (p = 0.001 and p = 0.002, respectively). Lesion detection was not significantly different among sequences or b-values (p = 0.174). There were no significant differences in measured ADC values within lesions between s-DWI (ADC: 0.97 [±0.09] × 10−3 mm2/s) and z-DWI (ADC: 0.99 [±0.11] × 10−3 mm2/s; p = 1.000). However, there was a trend toward lower values in IR m-b1500 DWI (ADC: 0.80 [±0.06] × 10−3 mm2/s) than in s-DWI (p = 0.090) and z-DWI (p = 0.110). Overall, image quality was superior and there were fewer image artifacts when using the advanced sequences (z-DWI + IR m-b1500 DWI) compared with s-DWI. Considering scan preferences, we found that the optimal combination was z-DWI with a calculated b1500, especially regarding examination time

AI-Supported Autonomous Uterus Reconstructions: First Application in MRI Using 3D SPACE with Iterative Denoising

Rationale and Objectives: T2-weighted imaging in at least two orthogonal planes is recommended for assessment of the uterus. To determine whether a convolutional neural network-based algorithm could be used for the re-constructions of uterus axes derived from a 3D SPACE with iterative denoising. Materials and Methods: 50 patients aged 18–81 (mean: 42) years who underwent an MRI examination of the uterus participated voluntarily in this prospective study after informed consent. In addition to a standard MRI pelvis protocol, a 3D SPACE research application sequence was acquired in sagittal orientation. Reconstructions for both the cervix and the cavum in the short and long axes were performed by a research trainee (T), an experienced radiologist (E), and the prototype software (P). In the next step, the reconstructions were evaluated anonymously by two experienced readers according to 5-point-Likert-Scales. In addition, the length of the cervical canal, the length of the cavum and the distance between the tube angles were measured on all reconstructions. Interobserver agreement was assessed for all ratings. Results: For all axes, significant differences were found between the scores of the reconstructions by research T, E and P. P received higher scores and was preferred significantly more often with the exception of the comparison of the reconstruction Cervix short of E (Cervix short: P vs. T: p = 0.02; P vs. E: p = 0.26; Cervix long: P vs. T: p = 0.01; P vs. E: p < 0.01; Cavum short: P vs. T: p = 0.01; P vs. E: p = 0.02; Cavum long: P vs. T: p < 0.01; P vs. E: p < 0.01). Regarding the measured diameters, (length of cervical canal/cavum/distance between tube angles) significantly larger diameters were recorded for P compared to E and T (Cervix long (mm): T: 25.43; E: 25.65; P: 26.65; Cavum short (mm): T: 26.24; E: 25.04; P: 27.33; Cavum long (mm): T: 31.98; E: 32.91; P: 34.41; P vs. T: p < 0.01); P vs. E: p = 0.04). Moderate to substantial agreement was found between Reader 1 and Reader 2 (range: 0.39–0.67). Conclusion: P was able to reconstruct the axes at least as well as or better than E and T. P could thereby lead to workflow facilitation and enable more efficient reporting of uterine MRI.ISSN:1076-633