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Purpose: To develop and validate a data acquisition scheme combined with a motion-resolved reconstruction and dictionary-matching-based parameter estimation to enable free-breathing isotropic resolution self-navigated whole-liver simultaneous water-specific T 1 ( wT 1 ) and T 2 ( wT 2 ) mapping for the characterization of diffuse and oncological liver diseases., Methods: The proposed data acquisition consists of a magnetization preparation pulse and a two-echo gradient echo readout with a radial stack-of-stars trajectory, repeated with different preparations to achieve different T 1 and T 2 contrasts in a fixed acquisition time of 6 min. Regularized reconstruction was performed using self-navigation to account for motion during the free-breathing acquisition, followed by water-fat separation. Bloch simulations of the sequence were applied to optimize the sequence timing for B 1 insensitivity at 3 T, to correct for relaxation-induced blurring, and to map T 1 and T 2 using a dictionary. The proposed method was validated on a water-fat phantom with varying relaxation properties and in 10 volunteers against imaging and spectroscopy reference values. The performance and robustness of the proposed method were evaluated in five patients with abdominal pathologies., Results: Simulations demonstrate good B 1 insensitivity of the proposed method in measuring T 1 and T 2 values. The proposed method produces co-registered wT 1 and wT 2 maps with a good agreement with reference methods (phantom: wT 1 = 1 . 02 wT 1,ref - 8 . 93 ms , R 2 = 0 . 991 ; wT 2 = 1 . 03 wT 2,ref + 0 . 73 ms , R 2 = 0 . 995 ). The proposed wT 1 and wT 2 mapping exhibits good repeatability and can be robustly performed in patients with pathologies., Conclusions: The proposed method allows whole-liver wT 1 and wT 2 quantification with high accuracy at isotropic resolution in a fixed acquisition time during free-breathing., (© 2024 The Author(s). NMR in Biomedicine published by John Wiley & Sons Ltd.)

Background: With rising breast augmentations worldwide, there is an increasing clinical need for an early and accurate detection of implant complications., Purpose: To compare the quality of chemical shift encoding-based (CSE) water-fat-silicone separation compared to double inversion recovery (DIR) silicone-only imaging in breast magnetic resonance imaging (MRI)., Material and Methods: This retrospective, single-center study included women with silicone implants subjected to 3-T MRI between January 2021 and March 2022. MRI included (i) two-dimensional silicone-only T2-weighted turbo spin echo DIR acquisition and (ii) three-dimensional CSE imaging based on multi-echo gradient-echo sequence enabling water-, fat-, and silicone-image separation. Images were evaluated and compared by three independent radiologists using a clinically established rating including differentiability of the silicone implant, visibility and contouring of the adjacent fibrous capsule, and accuracy of intralesional folds in a ranking of 1-5. The apparent contrast-to-noise (aCNR) was calculated., Results: In 71 women, the average quality of water-fat-silicone images from CSE imaging was assessed as "good" (assessment 4 ± 0.9). In 68 (96%) patients, CSE imaging achieved a concise delineation of the silicone implant and precise visualization of the fibrous capsule that was not distinguishable in DIR imaging. Implant ruptures were more easily detected in CSE imaging. The aCNR was higher in CSE compared to DIR imaging (18.43 ± 9.8 vs. 14.73 ± 2.5; P  = 0.002)., Conclusion: Intrinsically co-registered water-fat-silicone-separated CSE-based images enable a reliable assessment of silicone implants. The simultaneously improved differentiability of the implant and fibrous capsule may provide clinicians with a valuable tool for an accurate evaluation of implant integrity and early detection of potential complications., Competing Interests: Declaration of conflicting interestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Purpose: Liver T 1 mapping techniques typically require long breath holds or long scan time in free-breathing, need correction for B 1 + inhomogeneities and process composite (water and fat) signals. The purpose of this work is to accelerate the multi-slice acquisition of liver water selective T 1 (wT 1 ) mapping in a single breath hold, improving the k-space sampling efficiency., Methods: The proposed continuous inversion-recovery (IR) Look-Locker methodology combines a single-shot gradient echo spiral readout, Dixon processing and a dictionary-based analysis for liver wT 1 mapping at 3 T. The sequence parameters were adapted to obtain short scan times. The influence of fat, B 1 + inhomogeneities and TE on the estimation of T 1 was first assessed using simulations. The proposed method was then validated in a phantom and in 10 volunteers, comparing it with MRS and the modified Look-Locker inversion-recovery (MOLLI) method. Finally, the clinical feasibility was investigated by comparing wT 1 maps with clinical scans in nine patients., Results: The phantom results are in good agreement with MRS. The proposed method encodes the IR-curve for the liver wT 1 estimation, is minimally sensitive to B 1 + inhomogeneities and acquires one slice in 1.2 s. The volunteer results confirmed the multi-slice capability of the proposed method, acquiring nine slices in a breath hold of 11 s. The present work shows robustness to B 1 + inhomogeneities ( wT 1 , No B 1 + = 1.07 wT 1 , B 1 + - 45.63 , R 2 = 0.99 ) , good repeatability ( wT 1 , 2 ° = 1 . 0 wT 1 , 1 ° - 2.14 , R 2 = 0.96 ) and is in better agreement with MRS ( wT 1 = 0.92 wT 1 MRS + 103.28 , R 2 = 0.38 ) than is MOLLI ( wT 1 MOLLI = 0.76 wT 1 MRS + 254.43 , R 2 = 0.44 ) . The wT 1 maps in patients captured diverse lesions, thus showing their clinical feasibility., Conclusion: A single-shot spiral acquisition can be combined with a continuous IR Look-Locker method to perform rapid repeatable multi-slice liver water T 1 mapping at a rate of 1.2 s per slice without a B 1 + map. The proposed method is suitable for nine-slice liver clinical applications acquired in a single breath hold of 11 s., (© 2024 The Authors. NMR in Biomedicine published by John Wiley & Sons Ltd.)

Objectives: MR imaging-based proton density fat fraction (PDFF) and T2* imaging has shown to be useful for the evaluation of degenerative changes in the spine. Therefore, the aim of this study was to investigate the influence of myelotoxic chemotherapy on the PDFF and T2* of the thoracolumbar spine in comparison to changes in bone mineral density (BMD)., Methods: In this study, 19 patients were included who had received myelotoxic chemotherapy (MC) and had received a MR imaging scan of the thoracolumbar vertebrates before and after the MC. Every patient was matched for age, sex, and time between the MRI scans to two controls without MC. All patients underwent 3-T MR imaging including the thoracolumbar spine comprising chemical shift encoding-based water-fat imaging to extract PDFF and T2* maps. Moreover, trabecular BMD values were determined before and after chemotherapy. Longitudinal changes in PDFF and T2* were evaluated and compared to changes in BMD., Results: Absolute mean differences of PDFF values between scans before and after MC were at 8.7% (p = 0.01) and at -0.5% (p = 0.57) in the control group, resulting in significantly higher changes in PDFF in patients with MC (p = 0.008). BMD and T2* values neither showed significant changes in patients with nor in those without myelotoxic chemotherapy (p = 0.15 and p = 0.47). There was an inverse, yet non-significant correlation between changes in PDFF and BMD found in patients with myelotoxic chemotherapy (r = -0.41, p = 0.12)., Conclusion: Therefore, PDFF could be a useful non-invasive biomarker in order to detect changes in the bone marrow in patients receiving myelotoxic therapy., Clinical Relevance Statement: Using PDFF as a non-invasive biomarker for early bone marrow changes in oncologic patients undergoing myelotoxic treatment may help enable more targeted countermeasures at commencing states of bone marrow degradation and reduce risks of possible fragility fractures., Key Points: Quantifying changes in bone marrow fat fraction, as well as T2* caused by myelotoxic pharmaceuticals using proton density fat fraction, is feasible. Proton density fat fraction could potentially be established as a non-invasive biomarker for early bone marrow changes in oncologic patients undergoing myelotoxic treatment., (© 2023. The Author(s).)

Background: Tension-type headache (TTH) is the most prevalent primary headache disorder. Neck pain is commonly associated with primary headaches and the trigemino-cervical complex (TCC) refers to the convergence of trigeminal and cervical afferents onto neurons of the brainstem, thus conceptualizes the emergence of headache in relation to neck pain. However, no objective biomarkers exist for the myofascial involvement in primary headaches. This study aimed to investigate the involvement of the trapezius muscles in primary headache disorders by quantitative magnetic resonance imaging (MRI), and to explore associations between muscle T2 values and headache frequency and neck pain., Methods: This cohort study prospectively enrolled fifty participants (41 females, age range 20-31 years): 16 subjects with TTH only (TTH-), 12 with mixed-type TTH plus migraine (TTH+), and 22 healthy controls (HC). The participants completed fat-suppressed T2-prepared three-dimensional turbo spin-echo MRI, a headache diary (over 30 days prior to MRI), manual palpation (two weeks before MRI), and evaluation of neck pain (on the day of MRI). The bilateral trapezius muscles were manually segmented, followed by muscle T2 extraction. Associations between muscle T2 and the presence of neck pain as well as the number of days with headache (considering the 30 days prior to imaging using the headache calendar) were analyzed using regression models (adjusting for age, sex, and body mass index)., Results: The TTH+ group demonstrated the highest muscle T2 values (right side: 31.4 ± 1.2 ms, left side: 31.4 ± 0.8 ms) as compared to the TTH- group or HC group (p < 0.001). Muscle T2 was significantly associated with the number of headache days (β-coefficient: 2.04, p = 0.04) and the presence of neck pain (odds ratio: 2.26, p = 0.04). With muscle T2 as the predictor, the area under the curve for differentiating between HC and the TTH+ group was 0.82., Conclusions: Increased T2 of trapezius muscles may represent an objective imaging biomarker for myofascial involvement in primary headache disorders, which could help to improve patient phenotyping and therapy evaluation. Pathophysiologically, the increased muscle T2 values could be interpreted as a surrogate of neurogenic inflammation and peripheral sensitization within myofascial tissues., (© 2023. The Author(s).)

Objectives: There is a clinical need for a non-ionizing, quantitative assessment of breast density, as one of the strongest independent risk factors for breast cancer. This study aims to establish proton density fat fraction (PDFF) as a quantitative biomarker for fat tissue concentration in breast MRI and correlate mean breast PDFF to mammography., Methods: In this retrospective study, 193 women were routinely subjected to 3-T MRI using a six-echo chemical shift encoding-based water-fat sequence. Water-fat separation was based on a signal model accounting for a single T 2 * decay and a pre-calibrated 7-peak fat spectrum resulting in volumetric fat-only, water-only images, PDFF- and T 2 *-values. After semi-automated breast segmentation, PDFF and T 2 * values were determined for the entire breast and fibroglandular tissue. The mammographic and MRI-based breast density was classified by visual estimation using the American College of Radiology Breast Imaging Reporting and Data System categories (ACR A-D)., Results: The PDFF negatively correlated with mammographic and MRI breast density measurements (Spearman rho: -0.74, p < .001) and revealed a significant distinction between all four ACR categories. Mean T 2 * of the fibroglandular tissue correlated with increasing ACR categories (Spearman rho: 0.34, p < .001). The PDFF of the fibroglandular tissue showed a correlation with age (Pearson rho: 0.56, p = .03)., Conclusion: The proposed breast PDFF as an automated tissue fat concentration measurement is comparable with mammographic breast density estimations. Therefore, it is a promising approach to an accurate, user-independent, and non-ionizing breast density assessment that could be easily incorporated into clinical routine breast MRI exams., Key Points: • The proposed PDFF strongly negatively correlates with visually determined mammographic and MRI-based breast density estimations and therefore allows for an accurate, non-ionizing, and user-independent breast density measurement. • In combination with T2*, the PDFF can be used to track structural alterations in the composition of breast tissue for an individualized risk assessment for breast cancer., (© 2022. The Author(s).)

Background: Proton-density fat fraction (PDFF) and T2* of the vertebrae, as well as the cross-sectional area (CSA) of the paraspinal musculature (PSM), have been suggested as biomarkers for bone fragility. The aim of this study was to longitudinally assess changes in PDFF, T2* and CSA of the PSM over 6 months in patients with and without osteoporosis. Methods: Opportunistic bone mineral density (BMD) measurements (BMD < 120 mg/cm3) were obtained from a CT acquired during the clinical routine work up in osteoporotic/osteopenic patients (n = 29, mean age 72.37 ± 10.12 years, 16 women). These patients were frequency-matched for age and sex to subjects with normal BMD values (n = 29). All study patients underwent 3T MR imaging at baseline and 6-month follow up, including spoiled gradient echo sequences for chemical shift encoding-based water-fat separation, from which T2* and PDFF values of the lumbar spine and the PSM were obtained. Moreover, the CSA of the PSM was assessed longitudinally. Changes in T2*, PDFF and CSA over 6 months were calculated for the vertebrae and PSM and associations with baseline BMD values were assessed. Results: The change in CSA of the PSM over 6 months was significantly lower in the osteoporotic/osteopenic group (−91.5 ± 311.7 mm2), compared to the non-osteoporotic group, in which the CSA increased (29.9 ± 164.0 mm2, p = 0.03). In a further analysis, patients with higher vertebral PDFF at baseline showed a significantly stronger increase in vertebral T2*, compared to those patients with lower vertebral PDFF at baseline (0.9 ± 1.6 ms vs. 0.0 ± 1.8 ms, p = 0.04). Moreover, patients with higher PSM PDFF at baseline showed a significantly stronger increase in vertebral T2*, compared to those patients with lower PSM PDFF at baseline (0.9 ± 2.0 ms vs. 0.0 ± 1.3 ms, p = 0.03). Conclusion: The PSM CSA decreased significantly longitudinally in patients with osteoporosis/osteopenia, compared to those without. Additionally, higher vertebral and PSM PDFF at baseline were associated with stronger changes in vertebral bone marrow T2*. Therefore, longitudinal PDFF and T2* mapping may be useful quantitative radiation-free tools for the assessment and prediction of muscle and bone health in patients with suspected osteoporosis/osteopenia.

Background: The Pediatric Heart Network Normal Echocardiogram Database Study had unanticipated challenges. We sought to describe these challenges and lessons learned to improve the design of future studies., Methods: Challenges were divided into three categories: enrolment, echocardiographic imaging, and protocol violations. Memoranda, Core Lab reports, and adjudication logs were reviewed. A centre-level questionnaire provided information regarding local processes for data collection. Descriptive statistics were used, and chi-square tests determined differences in imaging quality., Results: For the 19 participating centres, challenges with enrolment included variations in Institutional Review Board definitions of "retrospective" eligibility, overestimation of non-White participants, centre categorisation of Hispanic participants that differed from National Institutes of Health definitions, and exclusion of potential participants due to missing demographic data. Institutional Review Board amendments resolved many of these challenges. There was an unanticipated burden imposed on centres due to high numbers of echocardiograms that were reviewed but failed to meet submission criteria. Additionally, image transfer software malfunctions delayed Core Lab image review and feedback. Between the early and late study periods, the proportion of unacceptable echocardiograms submitted to the Core Lab decreased (14 versus 7%, p < 0.01). Most protocol violations were from eligibility violations and inadvertent protected health information disclosure (overall 2.5%). Adjudication committee reviews led to protocol changes., Conclusions: Numerous challenges encountered during the Normal Echocardiogram Database Study prolonged study enrolment. The retrospective design and flaws in image transfer software were key impediments to study completion and should be considered when designing future studies collecting echocardiographic images as a primary outcome.

Shoulder pain is a common presentation in the emergency department. The list of differential diagnoses is broad. This article summarizes common diagnoses of shoulder pain, including bony, infectious, and connective tissue pathologies and their proper treatment. It also reviews which shoulder pain conditions are emergency diagnoses and need immediate treatment and which diagnoses need conservative management and outpatient follow-up., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: The reliability of left ventricular (LV) systolic functional indices calculated from blinded echocardiographic measurements of LV size has not been tested in a large cohort of healthy children. The objective of this study was to estimate interobserver variability in standard measurements of LV size and systolic function in children with normal cardiac anatomy and qualitatively normal function., Methods: The Pediatric Heart Network Normal Echocardiogram Database collected normal echocardiograms from healthy children ≤18 years old distributed equally by age, gender, and race. A core lab used two-dimensional echocardiograms to measure LV dimensions from which a separate data coordinating center calculated LV volumes and systolic functional indices. To evaluate interobserver variability, two independent expert pediatric echocardiographic observers remeasured LV dimensions on a subset of studies, while blinded to calculated volumes and functional indices., Results: Of 3,215 subjects with measurable images, 552 (17%) had a calculated LV shortening fraction (SF) < 25% and/or LV ejection fraction (EF) < 50%; the subjects were significantly younger and smaller than those with normal values. When the core lab and independent observer measurements were compared, individual LV size parameter intraclass correlation coefficients were high (0.81-0.99), indicating high reproducibility. The intraclass correlation coefficients were lower for SF (0.24) and EF (0.56). Comparing reviewers, 40/56 (71%) of those with an abnormal SF and 36/104 (35%) of those with a normal SF based on core lab measurements were calculated as abnormal from at least one independent observer. In contrast, an abnormal EF was less commonly calculated from the independent observers' repeat measures; only 9/47 (19%) of those with an abnormal EF and 8/113 (7%) of those with a normal EF based on core lab measurements were calculated as abnormal by at least one independent observer., Conclusions: Although blinded measurements of LV size show good reproducibility in healthy children, subsequently calculated LV functional indices reveal significant variability despite qualitatively normal systolic function. This suggests that, in clinical practice, abnormal SF/EF values may result in repeat measures of LV size to match the subjective assessment of function. Abnormal LV functional indices were more prevalent in younger, smaller children., (Copyright © 2019 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.)

Background/hypothesis/objectives: Postoperative complications after the Fontan operation for single ventricle heart disease are common and include persistent pleural drainage and prolonged length of hospital stay (LOS). Diastolic ventricular dysfunction may increase risk for postoperative complications by raising central venous pressures. We sought to determine the relationship between preoperative echocardiographic measurements of diastolic function, including myocardial deformation imaging, on (a) preoperative invasive catheterization measurements and (b) postoperative outcomes after the Fontan procedure., Design/methods: All patients that underwent Fontan procedure from 2011 to 2017 were included. Echocardiograms performed within 6 months prior to Fontan operation were evaluated. Measurements of ventricular global and diastolic strain and strain rate were performed offline with TomTec speckle tracking software. Other diastolic function measurements included atrioventricular valve inflow and annular tissue Doppler imaging. Diastolic function measurements were correlated with pre-Fontan catheterization measurements and postoperative Fontan outcomes using Spearman's rho. Multivariable logistic regression for a prolonged LOS (>75%ile for postoperative LOS) was performed to adjust for preoperative risk factors., Results: A total of 141 patients were included in the study. Majority had single morphologic right ventricle (58.9%). Median age at time of Fontan was 3.4 years (IQR 2.9-4). Median hospital LOS was 9 days (IQR 7-11). Circumferential diastolic strain rate weakly correlated with LOS (rho = -0.21, P = .01). There was no correlation between any other diastolic strain measurements and pre-Fontan end-diastolic pressure or postoperative LOS. In multivariable analysis, E/E' was the only echo measurement that predicted prolonged hospital LOS (OR 1.4, 95%CI: 1.1-1.8, P = .003)., Conclusion: Preoperative diastolic strain measurements did not have a strong association with postoperative Fontan outcomes. Increased E/E' ratio, however, did predict greater LOS after Fontan procedure, and may be useful in preoperative risk stratification. Future studies are needed to further assess the utility of diastolic strain imaging in the single-ventricle population., (© 2019 Wiley Periodicals, Inc.)

Background Heart size and function in children with single right ventricle (RV) anomalies may be influenced by shunt type at the Norwood procedure. We sought to identify shunt-related differences during early childhood after staged surgical palliations using echocardiography. Methods We compared echocardiographic indices of RV, neoaortic, and tricuspid valve size and function at 14 months, pre-Fontan, and 6 years in 241 subjects randomized to a Norwood procedure using either the modified Blalock-Taussig shunt or RV-to-pulmonary-artery shunt. Results At 6 years, the shunt groups did not differ significantly in any measure except for increased indexed neoaortic area in the modified Blalock-Taussig shunt. RV ejection fraction improved between pre-Fontan and 6 years in the RV-to-pulmonary artery shunt group but was stable in the modified Blalock-Taussig shunt group. For the entire cohort, RV diastolic and systolic size and functional indices were improved at 6 years compared with earlier measurements, and indexed tricuspid and neoaortic annular area decreased from 14 months to 6 years. The prevalence of ≥moderate tricuspid and neoaortic regurgitation was uncommon and did not vary by group or time period. Diminished RV ejection fraction at the 14-month study was predictive of late death/transplant; the hazard of late death/transplant when RV ejection fraction was <40% was tripled (hazard ratio, 3.18; 95% CI, 1.41-7.17). Conclusions By 6 years after staged palliation, shunt type has not impacted RV size and function, and RV and valvar size and function show beneficial remodeling. Poor RV systolic function at 14 months predicts worse late survival independent of the initial shunt type. Clinical Trial Registration URL: https://www.clinicaltrials.gov . Unique identifier: NCT00115934.

Background: Quantitative echocardiographic measurements of single ventricular (SV) function have not been incorporated into routine clinical practice., Methods: A clinical protocol, which included quantitative measurements of SV deformation (global circumferential and longitudinal strain and strain rate), standard deviation of time to peak systolic strain, myocardial performance index (MPI), dP/dT from an atrioventricular valve regurgitant jet, and superior mesenteric artery resistance index, was instituted for all patients with a history of Fontan procedure undergoing echocardiography. All measures were performed real time during clinically indicated studies and were included in clinical reports., Results: A total of 100 consecutive patients (mean age = 11.95±6.8 years, range 17 months-31.3 years) completed the protocol between September 1, 2014 to April 29, 2015. Deformation measures were completed in 100% of the studies, MPI in 93%, dP/dT in 55%, and superior mesenteric artery Doppler in 82%. The studies were reviewed to assess for efficiency in completing the protocol. The average time for image acquisition was 27.4±8.8 (range 10-62 minutes). The average time to perform deformation measures was 10.8±5.5 minutes (range 5-35 minutes) and time from beginning of imaging to report completion was 53.4±13.7 minutes (range 27-107 minutes). There was excellent inter-observer reliability when deformation indices were blindly repeated. Patients with a single left ventricle had significantly higher circumferential strain and strain rate, longitudinal strain and strain rate, and dP/dT compared to a single right ventricle. There were no differences in quantitative indices of ventricular function between patients <10 vs. >10 years post-Fontan., Conclusion: Advanced quantitative assessment of SV function post-Fontan can be consistently and efficiently performed real time during clinically indicated echocardiograms with excellent reliability., (© 2016, Wiley Periodicals, Inc.)

Initial surgical strategies in neonates with single left ventricular (LV) anatomy vary based on adequacy of pulmonary and systemic blood flow. Differing myocardial responses to these strategies, as reflected in indices of systolic function, ventricular size, and mass have not been well defined. We sought to evaluate single LV myocardial response to varied physiology and initial palliation and determine whether the response is consistent and predictable. Infants with single LV physiology were divided based on neonatal palliation: no palliation/PA band (NO); BT shunt only (BT); or Norwood procedure (NP). Echo measures were obtained at presentation, early post-bidirectional Glenn (BDG), late post-BDG follow-up, and post-Fontan procedure. Measures included ejection fraction, LV mass indexed to height 2.7 and end diastolic volume indexed to body surface area, and mass/volume ratio. The cohort included 38 children (13 NO, 13 BT, 12 NP). Ejection fraction was similar but depressed in all groups at all stages. LV mass was higher in the NP group than the BT group at early post-BDG (p = 0.03) and higher than both BT and NO groups (p < 0.01) at late post-BDG, but the difference was resolved by post-Fontan follow-up. The NP group had the most remarkable remodeling in LV size from BDG to Fontan, suggesting that volume unloading is most valuable in this subgroup. Ventricular remodeling can be identified by echocardiography in children with single LV physiology, despite variable initial surgical palliative strategies. Importantly, these initial surgical strategies do not result in significant differences after Fontan palliation during early childhood.

Background: The Single Ventricle Reconstruction trial demonstrated a transplantation-free survival advantage at 12-month follow-up for patients with right ventricle-pulmonary artery shunts (RVPAS) with the Norwood procedure compared with modified Blalock-Taussig shunts but similar survival and decreased global right ventricular (RV) function on longer term follow-up. The impact of the required ventriculotomy for the RVPAS remains unknown. The aim of this study was to compare echocardiography-derived RV deformation indices after stage 2 procedures in survivors with single RV anomalies enrolled in the Single Ventricle Reconstruction trial., Methods: Global and regional RV systolic longitudinal and circumferential strain and strain rate, ejection fraction, and short-axis percentage fractional area change were all derived by speckle-tracking echocardiography from protocol echocardiograms obtained at 14.3 ± 1.2 months. Student t tests or Wilcoxon rank sum tests were used to compare groups., Results: The cohort included 275 subjects (129 in the modified Blalock-Taussig shunt group and 146 in the RVPAS group). Longitudinal deformation could be quantified in 214 subjects (78%) and circumferential measures in 182 subjects (66%). RV ejection fraction and percentage fractional area change did not differ between groups. There were no significant differences between groups for global or regional longitudinal deformation. Circumferential indices showed abnormalities in deformation in the RVPAS group, with decreased global circumferential strain (P = .05), strain rate (P = .09), and anterior regional strain rate (P = .07) that approached statistical significance., Conclusions: RV myocardial deformation at 14 months, after stage 2 procedures, was not significantly altered by the type of initial shunt placed. However, abnormal trends were appreciated in circumferential deformation for the RVPAS group in the area of ventriculotomy that may represent early myocardial dysfunction. These data provide a basis for longer term RV deformation assessment in survivors after Norwood procedures., (Copyright © 2015 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.)

The results obtained using the Technical University of Gdansk Electroimpedance Mammograph (TUGEM) of a 3D phantom study are presented. The TUGEM system is briefly described. The hardware contains the measurement head and DSP-based identification modules controlled by a PC computer. A specially developed reconstruction algorithm, Regulated Correction Frequency Algebraic Reconstruction Technique (RCFART), is used to obtain 3D images. To visualize results, the Advance Visualization System (AVS) is used. It allows a powerful image processing on a fast workstation or on a high-performance computer. Results of three types of 3D conductivity perturbations used in the study (aluminum, Plexiglas, and cucumber) are shown. The relative volumes of perturbations less than 2% of the measurement chamber are easily evidenced.

The construction of the cell for measurement of complex electric conductivity is described. Two-chamber and four-electrode system with temperature stabilisation is developed. Guarding chamber and electrodes are used to minimise the leakage of current from the measurement chamber. The cell construction is examined by use of Finite Element Method. The model of the measurement cell is examined in order to improve the accuracy of measurements. The calibration procedure based on measurement of reference materials is presented. The frequency range of the cell is extended to 10 MHz with acceptable level of error. The examples of results from measurement breast normal and cancerous tissues are presented.

Although tracheal resections have been in use for quite some time, they were largely outweighed by procedures of plastic reconstruction, since tracheal resections were extensible to only 2 to 4 cm. At the present time, however, a resection length of up to 70% of the trachea, i. e. 7 to 8 cm, is impossible. The therapy of choice for most obstructive diseases of the trachea is the circular tracheal resection with end-to-end anastomosis. Plastic reconstruction is most indicated for stenoses of the cricoid cartilage. Tracheal protheses should only be used when a primary anastomosis cannot be carried out due to excessive tension. As a rule, this applies to resection lengths exceeding 7 to 8 cm.