Patient Re-Identification Based on Deep Metric Learning in Trunk Computed Tomography Images Acquired from Devices from Different Vendors.

During radiologic interpretation, radiologists read patient identifiers from the metadata of medical images to recognize the patient being examined. However, it is challenging for radiologists to identify "incorrect" metadata and patient identification errors. We propose a method that uses a patient re-identification technique to link correct metadata to an image set of computed tomography images of a trunk with lost or wrongly assigned metadata. This method is based on a feature vector matching technique that uses a deep feature extractor to adapt to the cross-vendor domain contained in the scout computed tomography image dataset. To identify "incorrect" metadata, we calculated the highest similarity score between a follow-up image and a stored baseline image linked to the correct metadata. The re-identification performance tests whether the image with the highest similarity score belongs to the same patient, i.e., whether the metadata attached to the image are correct. The similarity scores between the follow-up and baseline images for the same "correct" patients were generally greater than those for "incorrect" patients. The proposed feature extractor was sufficiently robust to extract individual distinguishable features without additional training, even for unknown scout computed tomography images. Furthermore, the proposed augmentation technique further improved the re-identification performance of the subset for different vendors by incorporating changes in width magnification due to changes in patient table height during each examination. We believe that metadata checking using the proposed method would help detect the metadata with an "incorrect" patient identifier assigned due to unavoidable errors such as human error.

Molecular crowding effect in Hantzch pyridine synthesis in polyethylene glycol aqueous solution.

In a molecular crowding environment, the kinetics and thermodynamics differ from those in a diluted solution. Although the molecular crowding effect has been extensively investigated, its fundamental kinetics and thermodynamics remain unclear. In this study, we investigated the change in the rate constant (k) of the Hantzch pyridine reaction in a molecular crowding environment using polyethylene glycol (PEG). While the k value increased to a PEG concentration (CPEG) of 10 vol%, a decreasing trend was observed for CPEG > 20 vol%. This intriguing behavior was analyzed based on the increase in reactant activity due to volume exclusion and the decrease in water activity due to osmotic pressure. Volume exclusion and osmotic pressure had opposing effects on the reaction, which were positive for volume exclusion and negative for osmotic pressure. We found that k decreased when the negative effect of the osmotic pressure surpassed the volume exclusion effect.

Compensation strategy of shoulder synergist muscles is not stereotypical in patients with rotator cuff repair.

Rotator cuff tear is a common shoulder injury that causes shoulder dysfunction and pain. Although surgical repair is the primary treatment for rotator cuff tear, it is well recognized that impaired force exertion of muscles connecting to the involved tendon and subsequent complemental change in the force exertion of synergist muscles persist even after repair. This study aimed to identify the compensation strategy of shoulder abductors by examining how synergist muscles respond to supraspinatus (SSP) muscle force deficit in patients with rotator cuff repair. Muscle shear modulus, an index of muscle force, was assessed for SSP, infraspinatus, upper trapezius, and middle deltoid muscles in repaired and contralateral control shoulders of 15 patients with unilateral tendon repair of the SSP muscle using ultrasound shear wave elastography while the patients passively or actively held their arm in shoulder abduction. In the repaired shoulder, the shear modulus of the SSP muscle declined, whereas that of other synergist muscles did not differ relative to that of the control. To find the association between the affected SSP and each of the synergist muscles, a regression analysis was used to assess the shear moduli at the population level. However, no association was observed between them. At the individual level, there was a tendency of variation among patients with regard to a specific muscle whose shear modulus complementarily increased. These results suggest that the compensation strategy for SSP muscle force deficit varies among individuals, being nonstereotypical in patients with rotator cuff injury.

Resistive Pulse Sensing on a Capillary-Assisted Microfluidic Platform for On-Site Single-Particle Analyses.

Capillary-assisted flow is valuable for utilizing microfluidics-based electrical sensing platforms at on-site locations by simplifying microfluidic operations and system construction; however, incorporating capillary-assisted flow in platforms requires easy microfluidic modification and stability over time for capillary-assisted flow generation and sensing performance. Herein, we report a capillary-assisted microfluidics-based electrical sensing platform using a one-step modification of polydimethylsiloxane (PDMS) with polyethylene glycol (PEG). As a model of electrical sensing platforms, this work focused on resistive pulse sensing (RPS) using a micropore in a microfluidic chip for label-free electrical detection of single analytes, and filling the micropore with an electrolyte is the first step to perform this RPS. The PEG-PDMS surfaces remained hydrophilic after ambient storage for 30 d and assisted in generating an electrolyte flow for filling the micropore with the electrolyte. We demonstrated the successful detection and size analysis of micrometer particles and bacterial cells based on RPS using the microfluidic chip stored in a dry state for 30 d. Combining this capillary-assisted microfluidic platform with a portable RPS system makes on-site detection and analysis of single pathogens possible.

Mechanical characteristic of supraspinatus muscle changes independent of its size and intramuscular fat in patient with rotator cuff repair.

PURPOSE: This study aimed i) to investigate the mechanical, morphological, and compositional characteristics of the supraspinatus muscle after rotator cuff repair by using ultrasound shear wave elastography (SWE) and B-mode imaging, and ii) to determine whether the morphological or compositional characteristics are associated with the mechanical characteristic of the supraspinatus during contraction. METHODS: Using SWE and B-mode imaging, active and passive shear moduli, muscle thickness, and echo intensity of the supraspinatus were measured from the repaired and contralateral control shoulders of 22 patients with rotator cuff repair. The shear modulus, muscle thickness, and echo intensity were compared between the repaired and control shoulders. The association between the active shear modulus and the other variables was determined. RESULTS: While the active and passive shear moduli were lower in the repaired shoulder compared to the control, the muscle thickness and echo intensity did not vary between them. Interestingly, the passive shear modulus was positively correlated with the active shear modulus only in the control shoulder. CONCLUSION: The mechanical characteristic of supraspinatus remains impaired, even without degenerative changes in the morphological and compositional characteristics after rotator cuff repair. Furthermore, the association between contractile and elastic characteristics in the supraspinatus was deteriorated in control shoulder.

Patient Identification Based on Deep Metric Learning for Preventing Human Errors in Follow-up X-Ray Examinations.

Biological fingerprints extracted from clinical images can be used for patient identity verification to determine misfiled clinical images in picture archiving and communication systems. However, such methods have not been incorporated into clinical use, and their performance can degrade with variability in the clinical images. Deep learning can be used to improve the performance of these methods. A novel method is proposed to automatically identify individuals among examined patients using posteroanterior (PA) and anteroposterior (AP) chest X-ray images. The proposed method uses deep metric learning based on a deep convolutional neural network (DCNN) to overcome the extreme classification requirements for patient validation and identification. It was trained on the NIH chest X-ray dataset (ChestX-ray8) in three steps: preprocessing, DCNN feature extraction with an EfficientNetV2-S backbone, and classification with deep metric learning. The proposed method was evaluated using two public datasets and two clinical chest X-ray image datasets containing data from patients undergoing screening and hospital care. A 1280-dimensional feature extractor pretrained for 300 epochs performed the best with an area under the receiver operating characteristic curve of 0.9894, an equal error rate of 0.0269, and a top-1 accuracy of 0.839 on the PadChest dataset containing both PA and AP view positions. The findings of this study provide considerable insights into the development of automated patient identification to reduce the possibility of medical malpractice due to human errors.

Application of statistical parametric mapping for comparison of scapular kinematics and EMG.

Scapular kinematics and EMG are frequently measured as a functional assessment of the shoulder. Previous studies have compared interval averaging for these time series data, but it is not clear whether this method exactly captures the dynamics of scapular kinematics and muscle activity. Statistical parametric mapping (SPM) can be used to compare time series data. The purpose of this study was to investigate whether there is a difference between the results of SPM and interval averaging (every 10° or 30°) in comparing scapular kinematics, EMG, and EMG ratio. Scapular kinematics and EMG of the upper trapezius (UT), middle trapezius (MT), and lower trapezius (LT) and serratus anterior (SA) were measured in 21 healthy males. Tasks included arm raising and lowering with or without load, and we compared scapular kinematics, EMG, and EMG ratio in the loaded and unloaded conditions. Results suggest disagreement between SPM and interval averaging. Characteristic results are that for scapular kinematics during lowering SPM showed a decrease in upward rotation in only the regions 113-65° and 42-30°, while interval averaging showed a decrease in all range. For EMG during lowering, SPM results were not significantly different in SA over 50-48 and 45-30°, while interval averaging suggested increased activity in all ranges. For EMG ratio during raising, SPM showed no significant difference, while interval averaging showed a decrease in UT/LT during the latter period. These results indicate that SPM provides better resolution regarding effect regions than interval averaging, and suggest that SPM may improve shoulder function assessment accuracy.

Biological fingerprint for patient verification using trunk scout views at various scan ranges in computed tomography.

Immediate verification of whether a patient being examined is correct is desirable, even if the scan ranges change during different examinations for the same patient. This study proposes an advanced biological fingerprint technique for the rapid and reliable verification of various scan ranges in computed tomography (CT) scans of the torso of the same patient. The method comprises the following steps: geometric correction of different scans, local feature extraction, mismatch elimination, and similarity evaluation. The geometric magnification correction was aligned at the scanner table height in the first two steps, and the local maxima were calculated as the local features. In the third step, local features from the follow-up scout image are matched to those in the corresponding baseline scout image via template matching and outlier elimination via a robust estimator. We evaluated the correspondence rate based on the inlier ratio between corresponding scout images. The ratio of inliers between the baseline and follow-up scout images was assessed as the similarity score. The clinical dataset, including chest, abdomen-pelvis, and chest-abdomen-pelvis scans, included 600 patients (372 men, 68 ± 12 years) who underwent two routine torso CT examinations. The highest area under the receiver operating characteristic curve (AUC) was 0.996, which was sufficient for patient verification. Moreover, the verification results were comparable to the conventional method, which uses scout images in the same scan range. Patient identity verification was achieved before the main scan, even in follow-up torso CT, under different scan ranges.

Agreement in rotator cuff muscles measurement between ultrasonography and magnetic resonance imaging.

Background/objective: It is important to assess the atrophy of the rotator cuff to better understand shoulder function and pain. Previously, magnetic resonance imaging has been used for the evaluation of atrophy of rotator cuff muscles, which is time consuming. Therefore, a measurement tool requiring little time and easy accessibility is clinically desirable to be used frequently in rehabilitation. Recently, rotator cuff muscles have been evaluated using ultrasonography. However, little is known about the agreement of evaluation in rotator cuff muscles between magnetic resonance imaging and ultrasonography. The purpose of this study was to demonstrate the agreement between the muscle thickness measurements of supraspinatus, infraspinatus, and teres minor muscles by ultrasonography and the cross-sectional area measured by magnetic resonance imaging in the patient with rotator cuff tears. Methods: A total of 47 patients with rotator cuff tears were enrolled. There were the 37 small tears, four medium tears, and six large tears, and the involved rotator cuff muscles were the supraspinatus in 37 shoulders, and the supraspinatus and infraspinatus in 10 shoulders. The measuring variables were muscle thickness and cross-sectional area of supraspinatus, infraspinatus, and teres minor muscles by using magnetic resonance imaging. Further, the muscle thickness of the rotator cuff were assessed using ultrasonography. A single regression model was used for demonstrating the agreement between the cross-sectional area measurement by magnetic resonance imaging and the muscle thickness measured using ultrasonography and magnetic resonance imaging of rotator cuff muscles. Additionally, the Bland-Altman plots between magnetic resonance imaging and ultrasonography was analyzed. Results: The cross-sectional area were correlated with the muscle thickness measurement of rotator cuff muscles by magnetic resonance imaging, significantly (supraspinatus: r = 0.84, infraspinatus: ρ = 0.63, teres minor: ρ = 0.61, all p < 0.001). There were significant agreements between the cross-sectional area measured by magnetic resonance imaging and muscle thickness measured by ultrasonography (supraspinatus: r = 0.80, infraspinatus: ρ = 0.78, teres minor: ρ = 0.74, all p < 0.001). Bland-Altman plots revealed significant correlations between the average and the difference of the two measurements in supraspinatus (r = 0.36, p = 0.012), infraspinatus (r = 0.38, p < 0.001), and teres minor (r = 0.42, p < 0.001). These results clarified the proportional bias between MRI and US. Conclusion: This study showed that, similar to magnetic resonance imaging, ultrasonography is a useful tool for assessing muscle atrophy of supraspinatus, infraspinatus, and teres minor muscles.

Morphology Control of Monomer-Polymer Hybrid Electron Acceptor for Bulk-Heterojunction Solar Cell Based on P3HT and Ti-Alkoxide with Ladder Polymer.

We report the morphology control of a nano-phase-separated structure in the photoactive layer (power generation layer) of organic-inorganic hybrid thin-film solar cells to develop highly functional electronic devices for societal applications. Organic and inorganic-organic hybrid bulk heterojunction solar cells offer several advantages, including low manufacturing costs, light weight, mechanical flexibility, and a potential to be recycled because they can be fabricated by coating them on substrates, such as films. In this study, by incorporating the carrier manager ladder polymer BBL as the third component in a conventional two-component power generation layer consisting of P3HT-the conventional polythiophene derivative and titanium alkoxide-we demonstrate that the phase-separated structure of bulk heterojunction solar cells can be controlled. Accordingly, we developed a discontinuous phase-separated structure suitable for charge transport, obtaining an energy conversion efficiency higher than that of the conventional two-component power generation layer. Titanium alkoxide is an electron acceptor and absorbs light with a wavelength lower than 500 nm. It is highly sensitive to LED light sources, including those used in homes and offices. A conversion efficiency of 4.02% under a 1000 lx LED light source was achieved. Hence, high-performance organic-inorganic hybrid bulk heterojunction solar cells with this three-component system can be used in indoor photovoltaic systems.

[New solutions for automated image recognition and identification: challenges to radiologic technology and forensic pathology].

This is a review on biological fingerprint for radiologic technology and forensic pathology by JSRT and JSMP (https://www.jsmp.org/en).

New solutions for automated image recognition and identification: challenges to radiologic technology and forensic pathology.

This paper outlines the history of biometrics for personal identification, the current status of the initial biological fingerprint techniques for digital chest radiography, and patient verification during medical imaging, such as computed tomography and magnetic resonance imaging. Automated image recognition and identification developed for clinical images without metadata could also be applied to the identification of victims in mass disasters or other unidentified individuals. The development of methods that are adaptive to a wide range of recent imaging modalities in the fields of radiologic technology, patient safety, forensic pathology, and forensic odontology is still in its early stages. However, its importance in practice will continue to increase in the future.

Quantification of muscle coordination underlying basic shoulder movements using muscle synergy extraction.

Numerous muscles around the shoulder joint are required to work in a coordinated manner, even when a basic shoulder movement is executed. Muscle synergy can be utilized as an index to determine muscle coordination. The purpose of the present study was to investigate the muscle coordination among different shoulder muscles underlying basic shoulder movements based on muscle synergy. Thirteen men performed 14 multiplanar shoulder movements; five movements were associated with elevation and lowering, while five were associated with horizontal abduction and adduction. The four additional movements were simple rotations at different positions. Muscle activity was measured from 12 muscle portions using surface electromyography. Using the dimensionality reduction technique, synergies were extracted first for each movement separately ("separate" synergies), and then for the global dataset (containing all movements; "global" synergies). The least number that provided 90% of the variance accounted for was selected as the optimal number of synergies. For each subject, approximately two separate synergies and approximately six global synergies with small residual values were extracted from the separate and global electromyography datasets, respectively. Specific patterns of these muscle synergies in each task were observed during each movement. In the cross-validation method, six global synergies explained 88.0 ± 1.3% of the global dataset. These findings indicate that muscle activities underlying basic shoulder movements are expressed as six units, and these units could be proxies for shoulder muscle coordination.

Thermodynamically Stable o-Quinodimethane: Synthesis, Structure, and Reactivity.

Thermal isomerization of cyclobutaphenanthrene to o-quinodimethane was investigated. Sterically congested substituents or electron-donating substituents on the four-membered ring promoted the ring-opening, affording o-quinodimethane in a relatively stable form. Isolation of the newly prepared o-quinodimethane allowed its structural elucidation and investigation of its potential reactivities. Dual [4+2] cycloaddition of an aryne and o-quinodimethane afforded tetrabenzopentacene, demonstrating the synthetic application of the isolated compound.

Comparison of shoulder muscle strength, cross-sectional area, acromiohumeral distance, and thickness of the supraspinatus tendon between symptomatic and asymptomatic patients with rotator cuff tears.

BACKGROUND: The purpose of this study was to demonstrate the differences in shoulder muscle strength, cross-sectional area of the rotator cuff muscles, acromiohumeral distance, and supraspinatus tendon thickness between symptomatic and asymptomatic patients with rotator cuff tears. METHODS: Thirty-two symptomatic patients and 23 asymptomatic patients with rotator cuff tears participated in this study. Data of the patients with any type of tear and supraspinatus tear were analyzed. We evaluated the isometric torque, cross-sectional area of the rotator cuff muscles, supraspinatus tendon thickness, acromiohumeral distance, range of motion, and Western Ontario Rotator Cuff Index. RESULTS: Asymptomatic patients showed greater isometric torque of shoulder abduction and internal rotation than symptomatic patients with any type of tear (P ≤ .01). Asymptomatic patients also demonstrated greater cross-sectional area of the supraspinatus (P < .01); however, there was no significant difference in the cross-sectional area of the other cuff muscles. There was also no significant difference in the supraspinatus tendon thickness (P = .10). The acromiohumeral distance at 90° of shoulder abduction was larger (P = .04) in asymptomatic patients. Additionally, similar tendencies were observed in the results of patients with supraspinatus tears, except for the isometric torque of shoulder external rotation. This torque was greater (P < .01) in asymptomatic patients. CONCLUSION: Asymptomatic patients showed greater shoulder range of motion, muscle strength of shoulder abduction and internal rotation, small occupation ratio of supraspinatus tendon thickness as a percentage of acromiohumeral distance, and large cross-sectional area of supraspinatus.

Synthesis of Enantiopure C2-Symmetric Anthracenophane and Dimerization En Route to Multiple-Bridged Cyclophanes.

We report the stereocontrolled synthesis of enantiopure C2-symmetric anthracenophanes and their derivatization to D2-symmetric multiple-bridged cyclophanes via photoinduced [4 + 4] dimerization.

Effect of different trunk postures on scapular muscle activities and kinematics during shoulder external rotation.

BACKGROUND: Shoulder external rotation at abduction (ER) is a notable motion in overhead sports because it could cause strong stress to the elbow and shoulder joint. However, no study has comprehensively investigated the effect of different trunk postures during ER. This study aimed to investigate the effect of different trunk postures on scapular kinematics and muscle activities during ER. METHODS: Fourteen healthy men performed active shoulder external rotation at 90° of abduction with the dominant arm in 15 trunk postures. At maximum shoulder external rotation in 15 trunk postures, including 4 flexion-extension, 6 trunk rotation, and 4 trunk side-bending postures, as well as upright posture as a control, scapular muscle activities and kinematics were recorded using surface electromyography and an electromagnetic tracking device, respectively. The data obtained in the flexion-extension, trunk rotation, and trunk side-bending postures were compared with those obtained in the upright posture. RESULTS: In the flexion-extension condition, scapular posterior tilt and external rotation significantly decreased, but the muscle activities of the lower trapezius and infraspinatus significantly increased in maximum trunk flexion. Moreover, scapular upward rotation and the activity of the serratus anterior significantly increased in maximum trunk extension. In the rotation condition, scapular posterior tilt and external rotation significantly decreased, but the activity of the serratus anterior significantly increased in the maximum contralateral trunk rotation posture. In the trunk side-bending condition, scapular posterior tilt and the external rotation angle significantly decreased. CONCLUSION: Trunk postures affected scapular kinematics and muscle activities during ER. Our results suggest that different trunk postures activate the lower trapezius and serratus anterior, which induce scapular posterior tilt.

Biological fingerprint using scout computed tomographic images for positive patient identification.

PURPOSE: Management of patient identification is an important issue that should be addressed to ensure patient safety while using modern healthcare systems. Patient identification errors can be mainly attributed to human errors or system problems. An error-tolerant system, such as a biometric system, should be able to prevent or mitigate potential misidentification occurrences. Herein, we propose the use of scout computed tomography (CT) images for biometric patient identity verification and present the quantitative accuracy outcomes of using this technique in a clinical setting. METHODS: Scout CT images acquired from routine examinations of the chest, abdomen, and pelvis were used as biological fingerprints. We evaluated the resemblance of the follow-up with the baseline image by comparing the estimates of the image characteristics using local feature extraction and matching algorithms. The verification performance was evaluated according to the receiver operating characteristic (ROC) curves, area under the ROC curves (AUC), and equal error rates (EER). The closed-set identification performance was evaluated according to the cumulative match characteristic curves and rank-one identification rates (R1). RESULTS: A total of 619 (383 males, 236 females, age range 21-92 years) patients who underwent baseline and follow-up chest-abdomen-pelvis CT scans on the same CT system were analyzed for verification and closed-set identification. The highest performances of AUC, EER, and R1 were 0.998, 1.22%, and 99.7%, respectively, in the considered evaluation range. Furthermore, to determine whether the performance decreased in the presence of metal artifacts, the patients were classified into two groups, namely scout images with (255 patients) and without (364 patients) metal artifacts, and the significance test was performed for two ROC curves using the unpaired Delong's test. No significant differences were found between the ROC performances in the presence and absence of metal artifacts when using a sufficient number of local features. Our proposed technique demonstrated that the performance was comparable to that of conventional biometrics methods when using chest, abdomen, and pelvis scout CT images. Thus, this method has the potential to discover inadequate patient information using the available chest, abdomen, and pelvis scout CT image; moreover, it can be applied widely to routine adult CT scans where no significant body structure effects due to illness or aging are present. CONCLUSIONS: Our proposed method can obtain accurate patient information available at the point-of-care and help healthcare providers verify whether a patient's identity is matched accurately. We believe the method to be a key solution for patient misidentification problems.

Comparison of scapular upward rotation during arm elevation in the scapular plane in healthy volunteers and patients with rotator cuff tears pre- and post-surgery.

BACKGROUND: Function loss caused by rotator cuff tears alters the scapular orientation, however, few prior studies have reported on scapular movements after rotator cuff repair. The purpose was to determine the scapular orientations before and after rotator cuff repair. METHODS: We recruited 14 healthy controls, 10 small and six massive rotator cuff tear in patients. The scapular upward rotation during arm elevation was analyzed using fluoroscopic imaging. FINDINGS: Before surgery, both rotator cuff groups demonstrated greater scapular upward rotation compared to healthy controls. Two months postoperation, the analyses showed significant differences between the patients with small rotator cuff tears and healthy controls at arm elevations of 90°, and between patients with both rotator cuff tear groups and healthy controls at arm elevations of 120°. At five months post-operation, significant differences still existed between the healthy controls and both rotator cuff groups. In regard to the temporal effects in the patients with small rotator cuff tears, the scapular upward rotation decreased significantly over time (2-5 months postoperation) at arm elevations of 120°. We did not identify a main effect owing to time in the patients with massive rotator cuff tears. INTERPRETATION: In patients with small rotator cuff tears, scapular upward rotation was reduced over the period of 2-5 months postoperation, however, the patients with massive rotator cuff tears showed greater scapular upward rotation throughout the experimental period. The results suggested that the execution of the rehabilitation program should consider that the tear size could affect scapular motion.