Attention-Aware Non-Rigid Image Registration for Accelerated MR Imaging.

Accurate motion estimation at high acceleration factors enables rapid motion-compensated reconstruction in Magnetic Resonance Imaging (MRI) without compromising the diagnostic image quality. In this work, we introduce an attention-aware deep learning-based framework that can perform non-rigid pairwise registration for fully sampled and accelerated MRI. We extract local visual representations to build similarity maps between the registered image pairs at multiple resolution levels and additionally leverage long-range contextual information using a transformer-based module to alleviate ambiguities in the presence of artifacts caused by undersampling. We combine local and global dependencies to perform simultaneous coarse and fine motion estimation. The proposed method was evaluated on in-house acquired fully sampled and accelerated data of 101 patients and 62 healthy subjects undergoing cardiac and thoracic MRI. The impact of motion estimation accuracy on the downstream task of motion-compensated reconstruction was analyzed. We demonstrate that our model derives reliable and consistent motion fields across different sampling trajectories (Cartesian and radial) and acceleration factors of up to 16x for cardiac motion and 30x for respiratory motion and achieves superior image quality in motion-compensated reconstruction qualitatively and quantitatively compared to conventional and recent deep learning-based approaches. The code is publicly available at https://github.com/lab-midas/GMARAFT.

Variable Stiffness and Damping Mechanism for CPR Manikin to Simulate Mechanical Properties of Human Chest.

OBJECTIVE: This study introduces a novel system that can simulate diverse mechanical properties of the human chest to enhance the experience of CPR training by reflecting realistic chest conditions of patients. METHODS: The proposed system consists of Variable stiffness mechanisms (VSMs) and Variable damper (VD) utilizing stretching silicone bands and dashpot dampers with controllable valves to modulate stiffness and damping, respectively. Cyclic loading was applied with a robot manipulator to the system. Compression force and displacement were measured and analyzed to evaluate the system's mechanical response. Long-term stability of the system was also validated. RESULTS: A non-linear response of the human chest under compression is realized through this design. Test results indicated non-linear force-displacement curves with hysteresis, similar to those observed in the chest of patients. Controlling the VSM and VD allowed for intentional changes in the slope and area of curves that are related to stiffness and damping, respectively. Stiffness and damping of the system were computed using performance test results. The stiffness ranged from 5.34 N/mm to 13.59 N/mm and the damping ranges from 0.127 N[Formula: see text] s/mm to 0.511 N[Formula: see text] s/mm. These properties cover a significant portion of the reported mechanical properties of the human chests. The system demonstrated satisfactory stability even when it was subjected to maximum stiffness conditions of the long-term compression test. CONCLUSION: The system is capable of emulating the mechanical properties and behavior of the human chests, thereby enhancing the CPR training experience.

Body physical parameters instead of water equivalent diameter to calculate size-specific dose estimate in adult chest CT.

This study aimed to investigate body physical parameters as substitutes for water equivalent diameter (Dw) while calculating size-specific dose estimates (SSDEs) during adult chest computed tomography (CT). A retrospective analysis was conducted on 776 patients. Patients were divided into training set (542 patients) and validation set (234 patients) according to a ratio of 7:3. The correlations between physical parameters and Dw were analyzed. The differences between SSDEsubstitutes and the reference SSDE (SSDEreference) were compared. Strong positive correlations were observed between body mass index (BMI) and Dw as well as between weight and Dw in overall, male, and female patients (all p < 0.001). The correlations between BMI and Dw were stronger than those between weight and Dw in overall, male, and female subjects (all p < 0.001). SSDEweight and SSDEBMI were not significantly different from SSDEreference (p > 0.05). The RMSEs of overall patients between SSDEweight and SSDEreference as well as between SSDEBMI and SSDEreference were 0.237 and 0.2, respectively. The use of sex-specific regression equations for BMI caused a slightly reduction in RMSE. Weight and BMI can be used as surrogate parameters for Dw when calculating SSDE in adult chest CT exams, with BMI being the preferred substitute parameter.

Effects of a physical exercise programme on bodyweight, body condition score and chest, abdominal and thigh circumferences in dogs.

BACKGROUND: Research on the effects of physical exercise on canine body composition is limited. The aim of this study was to investigate the effects of a physical exercise programme on bodyweight, body condition score (BCS) and chest, abdominal and thigh circumferences in dogs. Twenty-one healthy dogs of different breeds exercised together with their owners during an eight-week programme consisting of jogging and strength exercises. Standardised measurements were performed in triplicates with a measuring tape on standing dogs. Chest circumference was measured at three anatomical locations, abdomen at two and thigh at one. Data on bodyweight, BCS (9-point scale) and circumferences were analysed with mixed model repeated measures analyses to evaluate changes after the programme and effects of target distance. RESULTS: Seven dog owners choose a target distance of 2 km and 14 owners choose 5-10 km. Mean BCS decreased (P = 0.007) after the programme (5.1 ± 0.9 vs. 4.7 ± 0.6) but there was no effect of target distance. Almost all chest and abdominal circumference measurements decreased (P ≤ 0.007) with the 2 km group driving the reduction in chest circumference and the 5-10 km group driving the reduction in abdominal circumference. In contrast, thigh circumference (28.8 ± 0.4 vs. 30.2 ± 0.4) increased (P = 0.007) while bodyweight was maintained. There were positive correlations between BCS and abdominal/chest ratios before and after the programme (Pearson correlation; R square ≤ 0.43, P ≤ 0.0012) but the mean ratio remained constant. CONCLUSIONS: Results indicated a redistribution between total body fat and muscle mass in body composition of normal weight to slightly overweight dogs after the physical exercise programme. The use of bodyweight alone was not a reliable evaluation method to complement the BCS assessment. However, repeated measurements of chest, abdominal and thigh circumference might aid in the assessment of body composition in dogs performing physical exercise. Further research should include a control group and objective evaluations of total body fat and lean mass, in order to investigate the effectiveness of physical exercise as a freestanding method for decreasing BCS and increasing muscle mass in overweight dogs.

Extensive mycetoma in forearm, chest and neck due to Nocardia mexicana.

INTRODUCTION: Mycetoma is a chronic granulomatous inflammatory disease of the subcutaneous tissue, which affects deep structures and bone. Most cases of actinomycetoma are caused by members of the genus Nocardia. CASE PRESENTATION: Here we report the case of a 43-year-old male who presented a disseminated mycetoma on the forearm, chest and neck, characterized by enlarged and erythematous lesions through which seropurulent material drains, and numerous atrophic scars. Molecular identification was performed by 16S gene amplification and sequencing. Nocardia mexicana was identified with 100% identity. Trimethoprim-sulfamethoxazole, diaminodiphenyl sulfone and amikacin was a successful treatment after 6 months. CONCLUSIONS: Nocardia mexicana is a rare organism that causes mycetoma. We report a case of extensive mycetoma on the forearm with spread to the neck and thorax associated with manipulation of the mouth of a calf.

[Chest computed tomography manifestations in neonates with chronic granulomatous disease]. / æ–°ç”Ÿå„¿æ ¢æ€§è‚‰èŠ½è‚¿ç— èƒ¸éƒ¨è®¡ç®—æœºæ–­å±‚æ‰«æçš„ç‰¹å¾åˆ†æž.

OBJECTIVES: To study chest computed tomography (CT) manifestations in neonates with chronic granulomatous disease (CGD) to provide clues for early diagnosis of this disease. METHODS: A retrospective analysis was conducted on the clinical data and chest CT scan results of neonates diagnosed with CGD from January 2015 to December 2022 at Anhui Provincial Children's Hospital. RESULTS: Nine neonates with CGD were included, with eight presenting respiratory symptoms as the initial sign. Chest CT findings included: consolidation in all 9 cases; nodules in all 9 cases, characterized by multiple, variably sized scattered nodules in both lungs; masses in 4 cases; cavities in 3 cases; abscesses in 6 cases; bronchial stenosis in 2 cases; pleural effusion, interstitial changes, and mediastinal lymphadenopathy each in 1 case. CT enhancement scans showed nodules and masses with uneven or ring-shaped enhancement; no signs of pulmonary emphysema, lung calcification, halo signs, crescent signs, bronchiectasis, or scar lesions were observed. There was no evidence of rib or vertebral bone destruction. Fungal infections were present in 8 of the 9 cases, including 6 with Aspergillus infections; three of these involved mixed infections with Aspergillus, with masses most commonly associated with mixed Aspergillus infections (3/4). CONCLUSIONS: The primary manifestations of neonatal CGD on chest CT are consolidation, nodules, and/or masses, with Aspergillus as a common pathogen. These features can serve as early diagnostic clues for neonatal CGD.

Radiology of fibrosis. Part I: Thoracic organs.

Sustained injury from factors such as hypoxia, infection, or physical damage may provoke improper tissue repair and the anomalous deposition of connective tissue that causes fibrosis. This phenomenon may take place in any organ, ultimately leading to their dysfunction and eventual failure. Tissue fibrosis has also been found to be central in both the process of carcinogenesis and cancer progression. Thus, its prompt diagnosis and regular monitoring is necessary for implementing effective disease-modifying interventions aiming to reduce mortality and improve overall quality of life. While significant research has been conducted on these subjects, a comprehensive understanding of how their relationship manifests through modern imaging techniques remains to be established. This work intends to provide a comprehensive overview of imaging technologies relevant to the detection of fibrosis affecting thoracic organs as well as to explore potential future advancements in this field.

Sex differences in chest electrical impedance tomography findings.

Objective.Electrical impedance tomography (EIT) has been used to determine regional lung ventilation distribution in humans for decades, however, the effect of biological sex on the findings has hardly ever been examined. The aim of our study was to determine if the spatial distribution of ventilation assessed by EIT during quiet breathing was influenced by biological sex.Approach.219 adults with no known acute or chronic lung disease were examined in sitting position with the EIT electrodes placed around the lower chest (6th intercostal space). EIT data were recorded at 33 images/s during quiet breathing for 60 s. Regional tidal impedance variation was calculated in all EIT image pixels and the spatial distribution of the values was determined using the established EIT measures of centre of ventilation in ventrodorsal (CoVvd) and right-to-left direction (CoVrl), the dorsal and right fraction of ventilation, and ventilation defect score.Main results.After exclusion of one subject due to insufficient electrode contact, 218 data sets were analysed (120 men, 98 women) (age: 53 ± 18 vs 50 ± 16 yr (p= 0.2607), body mass index: 26.4 ± 4.0 vs 26.4 ± 6.6 kg m-2(p= 0.9158), mean ± SD). Highly significant differences in ventilation distribution were identified between men and women between the right and left chest sides (CoVrl: 47.0 ± 2.9 vs 48.8 ± 3.3% of chest diameter (p< 0.0001), right fraction of ventilation: 0.573 ± 0.067 vs 0.539 ± 0.071 (p= 0.0004)) and less significant in the ventrodorsal direction (CoVvd: 55.6 ± 4.2 vs 54.5 ± 3.6% of chest diameter (p= 0.0364), dorsal fraction of ventilation: 0.650 ± 0.121 vs 0.625 ± 0.104 (p= 0.1155)). Ventilation defect score higher than one was found in 42.5% of men but only in 16.6% of women.Significance.Biological sex needs to be considered when EIT findings acquired in upright subjects in a rather caudal examination plane are interpreted. Sex differences in chest anatomy and thoracoabdominal mechanics may explain the results.

Firefighter uncompensable heat stress results in excessive upper body temperatures measured by infrared thermography: Implications for cooling strategies.

This research sought to evaluate the thermal zones of the upper body and firefighter personal protective equipment (PPE) immediately following uncompensable heat stress (0.03 °C increase/min). We hypothesized that the frontal portion of the head and the inside of the firefighter helmet would be the hottest as measured by infrared thermography. This hypothesis was due to previous research demonstrating that the head accounts for ∼8-10% of the body surface area, but it accounts for ∼20% of the overall body heat dissipation during moderate exercise. Twenty participants performed a 21-min graded treadmill exercise protocol (Altered Modified Naughton) in an environmental chamber (35 °C, 50 % humidity) in firefighter PPE. The body areas analyzed were the frontal area of the head, chest, abdomen, arm, neck, upper back, and lower back. The areas of the PPE that were analyzed were the inside of the helmet and the jacket. The hottest areas of the body post-exercise were the frontal area of the head (mean: 37.3 ± 0.4 °C), chest (mean: 37.5 ± 0.3 °C), and upper back (mean: 37.3 ± 0.4 °C). The coldest area of the upper body was the abdomen (mean: 36.1 ± 0.4 °C). The peak temperature of the inside of the helmet increased (p < 0.001) by 9.8 °C from 27.7 ± 1.6 °C to 37.4 ± 0.7 °C, and the inside of the jacket increased (p < 0.001) by 7.3 °C from 29.2 ± 1.7 °C to 36.5 ± 0.4 °C. The results of this study are relevant for cooling strategies for firefighters.

Is there a connection between spine alignment, chest mobility, shoulder joint and respiratory parameters of patients with ankylosing spondylitis?

INTRODUCTION: Ankylosing spondylitis is chronic progressive disease, which decrease functions of musculoskeletal system including chest area. Those changes influences respiratory mechanics, worsen conditions of proper ventilation of lungs. OBJECTIVES: Rating of functional and respiratory parameters and dependence between them at patients with ankylosing spondylitis. MATERIALS & METHODS: The study included 45 patients with diagnosed ankylosing spondylitis. Chest and upper limbs mobility, resting spinal curvature alignment were assessed, and respiratory parameters were measured in a plethysmographic chamber JAGGER MasterScreen Body. RESULTS: Ankylosing spondylitis patients had lower respiratory parameters especially sReff, and FRC. Restriction of chest and upper limbs mobility was also demonstrated. Forward head extension was observed based on the occipital wall test. Correlations between functional parameters and correlations between functional and respiratory parameters were shown, in particular MIP, MEP, sReff, Rtot, TLC, ERV. CONCLUSIONS: The study confirmed a decrease in functional and respiratory parameters in the examined patients with ankylosing spondylitis compared to the applicable standards. A significant relationship was found between functional parameters in the upper body and respiratory parameters, which worsen with increasing thoracic dysfunction. The obtained results indicate the directions of therapy that should be taken into account to improve respiratory parameters and reduce respiratory dysfunction in these patients. Chest-focused physiotherapy appears to be an important element in improving function in patients with ankylosing spondylitis.

Biomechanical properties of the human superficial fascia: Site-specific variability and anisotropy of abdominal and thoracic regions.

Superficial fascia is a fibrofatty tissue found throughout the body. Initially described in relation to hernias, it has only recently received attention from the scientific community due to new evidence on its role in force transmission and structural integrity of the body. Considering initial difficulties in its anatomical identification, to date, a characterization of the superficial fascia through mechanical tests is still lacking. The mechanical properties of human superficial fasciae of abdominal and thoracic districts (back) of different subjects (n = 4) were then investigated, focusing on anisotropy and viscoelasticity. Experimental tests were performed on samples taken in two perpendicular directions according to body planes (cranio-caudal and latero-medial axes). Data collected from two different uniaxial tensile protocols, failure (i.e., ultimate tensile strength and strain at break, Young's modulus and toughness) and stress-relaxation (i.e., residual stress), were processed and then grouped for statistical analysis. Failure tests confirmed tissue anisotropy, revealing the stiffer nature of the latero-medial direction compared to the cranio-caudal one, for both the districts (with a ratio of the respective Young's moduli close to 2). Furthermore, the thoracic region exhibited significantly greater strength and resultant Young's modulus compared to the abdomen (with greater results along the latero-medial direction, such as 6.13 ± 3.11 MPa versus 0.85 ± 0.39 MPa and 24.87 ± 15.23 MPa versus 3.19 ± 1.62 MPa, respectively). On the contrary, both regions displayed similar strain at break (varying between 38 and 47%), with no clear dependence from the loading directions. Stress-relaxation tests highlighted the viscous behavior of the superficial fascia, with no significant differences in the stress decay between directions and districts (35-38% of residual stress after 300 s). All these collected results represent the starting point for a more in-depth knowledge of the mechanical characterization of the superficial fascia, which can have direct implications in the design, implementation, and effectiveness of site-specific treatments.

Bottom-up butterfly model with thorax-pitch control and wing-pitch flexibility.

The diversity in butterfly morphology has attracted many people around the world since ancient times. Despite morphological diversity, the wing and body kinematics of butterflies have several common features. In the present study, we constructed a bottom-up butterfly model, whose morphology and kinematics are simplified while preserving the important features of butterflies. The present bottom-up butterfly model is composed of two trapezoidal wings and a rod-shaped body with a thorax and abdomen. Its wings are flapped downward in the downstroke and backward in the upstroke by changing the geometric angle of attack (AOA). The geometric AOA is determined by the thorax-pitch and wing-pitch angles. The thorax-pitch angle is actively controlled by abdominal undulation, and the wing-pitch angle is passively determined because of a rotary spring representing the basalar and subalar muscles connecting the wings and thorax. We investigated the effectiveness of abdominal undulation for thorax-pitch control and how wing-pitch flexibility affects aerodynamic-force generation and thorax-pitch control, through numerical simulations using the immersed boundary-lattice Boltzmann method. As a result, the thorax-pitch angle perfectly follows the desired angle through abdominal undulation. In addition, there is an optimal wing-pitch flexibility that maximizes the flying speed in both the forward and upward directions, but the effect of wing-pitch flexibility on thorax-pitch control is not significant. Finally, we compared the flight behavior of the present bottom-up butterfly model with that of an actual butterfly. It was found that the present model does not reproduce reasonable body kinematics but can provide reasonable aerodynamics in butterfly flights.

[Research of electrical impedance tomography based on multilayer artificial neural network optimized by Hadamard product for human-chest models].

Electrical impedance tomography (EIT) is a non-radiation, non-invasive visual diagnostic technique. In order to improve the imaging resolution and the removing artifacts capability of the reconstruction algorithms for electrical impedance imaging in human-chest models, the HMANN algorithm was proposed using the Hadamard product to optimize multilayer artificial neural networks (MANN). The reconstructed images of the HMANN algorithm were compared with those of the generalized vector sampled pattern matching (GVSPM) algorithm, truncated singular value decomposition (TSVD) algorithm, backpropagation (BP) neural network algorithm, and traditional MANN algorithm. The simulation results showed that the correlation coefficient of the reconstructed images obtained by the HMANN algorithm was increased by 17.30% in the circular cross-section models compared with the MANN algorithm. It was increased by 13.98% in the lung cross-section models. In the lung cross-section models, some of the correlation coefficients obtained by the HMANN algorithm would decrease. Nevertheless, the HMANN algorithm retained the image information of the MANN algorithm in all models, and the HMANN algorithm had fewer artifacts in the reconstructed images. The distinguishability between the objects and the background was better compared with the traditional MANN algorithm. The algorithm could improve the correlation coefficient of the reconstructed images, and effectively remove the artifacts, which provides a new direction to effectively improve the quality of the reconstructed images for EIT.

Congenital Chest Lesions and Interventions.

Anomalies of the fetal chest require advanced imaging with ultrasound and MR imaging as well as expertise on the part of the interpreting pediatric radiologist. Congenital diaphragmatic hernia and congenital lung malformation are the most frequently seen, and in both conditions, the radiologist should provide both detailed anatomic description and measurement data for prognostication. This article provides a detailed approach to imaging the anatomy, in-depth explanation of available measurements and prognostic value, and keys to identifying candidates for fetal intervention. Less common congenital lung tumors and mediastinal and chest wall masses are also reviewed.

Measuring gait parameters from a single chest-worn accelerometer in healthy individuals: a validation study.

Digital health technologies (DHTs) are increasingly being adopted in clinical trials, as they enable objective evaluations of health parameters in free-living environments. Although lumbar accelerometers notably provide reliable gait parameters, embedding accelerometers in chest devices, already used for vital signs monitoring, could capture a more comprehensive picture of participants' wellbeing, while reducing the burden of multiple devices. Here we assess the validity of gait parameters measured from a chest accelerometer. Twenty healthy adults (13 females, mean ± sd age: 33.9 ± 9.1 years) instrumented with lumbar and chest accelerometers underwent in-lab and outside-lab walking tasks, while monitored with reference devices (an instrumented mat, and a 6-accelerometers set). Gait parameters were extracted from chest and lumbar accelerometers using our open-source Scikit Digital Health gait (SKDH-gait) algorithm, and compared against reference values via Bland-Altman plots, Pearson's correlation, and intraclass correlation coefficient. Mixed effects regression models were performed to investigate the effect of device, task, and their interaction. Gait parameters derived from chest and lumbar accelerometers showed no significant difference and excellent agreement across all tasks, as well as good-to-excellent agreement and strong correlation against reference values, thus supporting the deployment of a single multimodal chest device in clinical trials, to simultaneously measure gait and vital signs.Trial Registration: The study was reviewed and approved by the Advarra IRB (protocol number: Pro00043100).

DKCNN: Improving deep kernel convolutional neural network-based COVID-19 identification from CT images of the chest.

BACKGROUND: An efficient deep convolutional neural network (DeepCNN) is proposed in this article for the classification of Covid-19 disease. OBJECTIVE: A novel structure known as the Pointwise-Temporal-pointwise convolution unit is developed incorporated with the varying kernel-based depth wise temporal convolution before and after the pointwise convolution operations. METHODS: The outcome is optimized by the Slap Swarm algorithm (SSA). The proposed Deep CNN is composed of depth wise temporal convolution and end-to-end automatic detection of disease. First, the datasets SARS-COV-2 Ct-Scan Dataset and CT scan COVID Prediction dataset are preprocessed using the min-max approach and the features are extracted for further processing. RESULTS: The experimental analysis is conducted between the proposed and some state-of-art works and stated that the proposed work effectively classifies the disease than the other approaches. CONCLUSION: The proposed structural unit is used to design the deep CNN with the increasing kernel sizes. The classification process is improved by the inclusion of depth wise temporal convolutions along with the kernel variation. The computational complexity is reduced by the introduction of stride convolutions are used in the residual linkage among the adjacent structural units.

¿Será realmente una verdadera comunicación interventricular? / Could it really be a true ventricular septal defect?

Ventricular septal defect (VSD) is one of the most common congenital defects. It has a wide variety of clinical spectrum of presentation depending on the location and size of the defect. Generally, small restrictive VSDs present spontaneous closure during follow-up. A clinical case is presented with suspected persistent perimembranous VSD, with described intraoperative anatomical findings of aneurysmal cribriform membrane, ruling out VSD.

La comunicación interventricular (CIV) es uno de los defectos congénitos más comunes. Tiene una amplia variedad de espectro clínico de presentación dependiendo de la localización y tamaño del defecto. Por lo general, en los CIV restrictivos pequeños presentan un cierre espontáneo durante el seguimiento. Se presenta un caso clínico con sospecha de CIV perimembranosa persistente, con hallazgos anatómicos intraoperatorios descritos de membrana cribiforme aneurismática descartandose CIV.

Digital phantom versus patient-specific radiation dosimetry in adult routine thorax CT examinations.

PURPOSE: The aim of this study was to compare the organ doses assessed through a digital phantom-based and a patient specific-based dosimetric tool in adult routine thorax computed tomography (CT) examinations with reference to physical dose measurements performed in anthropomorphic phantoms. METHODS: Two Monte Carlo based dose calculation tools were used to assess organ doses in routine adult thorax CT examinations. These were a digital phantom-based dosimetry tool (NCICT, National Cancer Institute, USA) and a patient-specific individualized dosimetry tool (ImpactMC, CT Imaging GmbH, Germany). Digital phantoms and patients were classified in four groups according to their water equivalent diameter (Dw). Normalized to volume computed tomography dose index (CTDIvol), organ dose was assessed for lungs, esophagus, heart, breast, active bone marrow, and skin. Organ doses were compared to measurements performed using thermoluminescent detectors (TLDs) in two physical anthropomorphic phantoms that simulate the average adult individual as a male (Alderson Research Labs, USA) and as a female (ATOM Phantoms, USA). RESULTS: The average percent difference of NCICT to TLD and ImpactMC to TLD dose measurements across all organs in both sexes was 13% and 6%, respectively. The average ± 1 standard deviation in dose values across all organs with NCICT, ImpactMC, and TLDs was ± 0.06 (mGy/mGy), ± 0.19 (mGy/mGy), and ± 0.13 (mGy/mGy), respectively. Organ doses decreased with increasing Dw in both NCICT and ImpactMC. CONCLUSION: Organ doses estimated with ImpactMC were in closer agreement to TLDs compared to NCICT. This may be attributed to the inherent property of ImpactMC methodology to generate phantoms that resemble the realistic anatomy of the examined patient as opposed to NCICT methodology that incorporates an anatomical discrepancy between phantoms and patients.