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This clinical report describes how a hollow obturator prosthesis was designed and fabricated for an 82-year-old partially edentulous patient with a large palatal defect. Computer-aided design (CAD) was used to design, articulate, and align the mandibular denture with the obturator prosthesis. The prosthesis was printed, adjusted chairside, rescanned, and made hollow by using a CAD software program. The prosthesis was printed in resin with a dental 3D printer. Quantitative evaluations of clinical (prosthesis dimensions, rest, and occlusal vertical dimensions) and virtual (surface area, volume, weight, interpoint mismatches, spatial overlap) parameters found that the 3D-printed prosthesis required an additional 5% chairside modification. The greatest differences in volume (24.7% less) and weight (22.2% less) were observed when the modified obturator bulb was made hollow via CAD. Hollowing the bulb, therefore, reduced the spatial overlap in volume by 16.8%.

Scientific simulations on high-performance computing (HPC) systems can generate large amounts of floating-point data per run. As compared to lossless compressors, lossy compressors, such as SZ and ZFP, can reduce data volume more aggressively while maintaining the usefulness of the data. However, a reduction ratio of more than two orders of magnitude is almost impossible without seriously distorting the data. In deep learning, the autoencoder has shown potential for data compression. Whether the autoencoder can deliver similar performance on scientific data, however, is unknown. In this paper, we for the first time conduct a comprehensive study on the use of autoencoders to compress real-world scientific data and illustrate several key findings on using autoencoders for scientific data reduction. We implement an autoencoder-based compression prototype to reduce floating-point data. Our study shows that the out-of-the-box implementation needs to be further tuned in order to achieve high compression ratios and satisfactory error bounds. Our evaluation results show that, for most test datasets, the tuned autoencoder outperforms SZ by 2 to 4X, and ZFP by 10 to 50X in compression ratios, respectively. Our practices and lessons learned in this work can direct future optimizations for using autoencoders to compress scientific data.

Background: The relationship between anterior cruciate ligament (ACL) injury and anatomical structures is still a topic of debate. Purpose: The aim of this study was to compare knee geometry in demographically matched ACL-injured and ACL-intact athletes. Methods: We conducted a case-control study comparing 2 groups, each consisting of 55 professional athletes (44 men and 11 women): 1 group with complete ACL tears (cases) and 1 group with intact ACLs (controls). The groups were compared using magnetic resonance imaging (MRI) in terms of intercondylar notch geometry, tibial plateau characteristics, and ACL volume. Results: Among cases and controls, we found the cases had lower notch width (20.24 ± 2.68 mm vs. 22.04 ± 2.56 mm, respectively) and notch width index (0.29 ± 0.03 vs. 0.31 ± 0.03, respectively). The mean ACL volume in the cases (1181.63 mm3 ± 326 mm3) was also lower than in controls (1352.61 mm3 ± 279.84 mm3). The parameters of tibial slope geometry were comparable between groups. In addition, women had lower ACL volume than men (1254 ± 310 mm3 vs. 890 ± 267 mm3, respectively) and higher medial posterior tibial slope (4.76 ± 2.6 vs. 6.63 ± 1.83, respectively). Among cases, women had narrower notch width than men (16.9 ± 2.42 mm vs. 21.08 ± 2.03 mm). However, notch width index was comparable between male (0.3 ± 0.02) and female (0.28 ± 0.03) cases. Conclusion: Our findings suggest that narrow notch width and low ACL volume may enhance the risk of ACL injury among athletes. There was no association found between posterior tibial slope and ACL injury between athletes with injured ACLs and controls. Further study is indicated.

Background The majority of fetal structural defects can be detected in the second trimester, thus this is the main time for screening for structural defects. 3D imaging of the fetal brain does not create a common part of this screening. Methods This prospective observational study was conducted at the Fetal Medicine Center of The Gynecological-Obstetrical Department of the University Hospital Olomouc in years 2017- 2020. The study sample was 451 consecutively scanned morphologically normal fetuses attending for routine second trimester anatomical survey at 20-22 weeks of pregnancy. A transabdominal 3D ultrasound volume acquisition of fetal brain was obtained from an axial and sagittal plane using skull sutures as an acoustic window. Results Both the corpus callosum (CC) and the vermis (VC) were detected in 51.7% of examinations in the sagittal plane, and in 31.7% in the axial plane. In 61.9% of the examinations, there was at least partial detection in both planes. Maternal BMI was found to be the only significant predictor of the quality of imaging in both planes. Conclusion 3D acquisition of fetal brain images in the sagittal plane followed by manipulation of acquired volume was valuable in assessment of corpus callosum and cerebellar vermis. This allows reconstruction of the sagittal plane that can be difficult to obtain in 2D imaging.

Background: Tumor regression grade (TRG) correlates with prognosis in patients with locally advanced rectal cancer (LARC), but there is controversy regarding the use of magnetic resonance imaging (MRI) for determining TRG. This study to evaluate the diagnostic value of change rate in signal intensity (SI) and volume (V) from MRI to TRG following preoperative chemoradiotherapy (CRT) in patiens with LARC.Materials and methods: This retrospective analysis examined 82 LARC patients who were admitted to our institution between Oct 2017 and Oct 2019. Patients underwent pre- and post-CRT T2-weighted (T2W), diffusion-weighted (DW)/apparent diffusion coefficient (ADC), and contrast-enhanced T1-weighted (ceT1W) MRI. Change rate of volume and relative SI ratio(%△V and %△SIR) from each sequence were determined. All LARCs were confirmed pathologically and classified into TRG 0, 1, 2 and 3. Descriptive statistics and receiver operating characteristic (ROC) analysis, with calculation of area under the curve (AUC), were used to compare the diagnostic performances. Results: Sixteen patients had TRG-0, 15 had TRG-1, 35 had TRG-2, and 16 had TRG-3. Except for ADC-%△SIR, the remaining%△V and %△SIR on T1W, DWI, and ceT1W had significant differences among the four groups. %△V and/or %△SIR did not distinguish TRG-1 from TRG-2 nor TRG-2 from TRG-3, but differences between other TRGs were identified by %△V and/or %△SIR on T2W, DWI, and ceT1W. The combined use of DW-%△V and T2W-%△SIR provided the best diagnostic performance in distinguishing of TRG-0 from TRG-2 (AUC: 0.954) and from TRG-3 (AUC: 1.000).Conclusions: Preoperative MRI of LARC patients can determine TRG and may improve selection of the preoperative therapy.

Statement of problem The anatomic complexity of the ear challenges conventional maxillofacial prosthetic rehabilitation. The introduction of specialized scanning hardware integrated into computer-aided design and computer-aided manufacturing (CAD-CAM) workflows has mitigated these challenges. Currently, the scanning hardware required for digital data acquisition is expensive and not readily available for prosthodontists in developing regions. Purpose The purpose of this virtual analysis study was to compare the accuracy and precision of 3-dimensional (3D) ear models generated by scanning gypsum casts with a smartphone camera and a desktop laser scanner. Material and methods Six ear casts were fabricated from green dental gypsum and scanned with a laser scanner. The resultant 3D models were exported as standard tessellation language (STL) files. A stereophotogrammetry system was fabricated by using a motorized turntable and an automated microcontroller photograph capturing interface. A total of 48 images were captured from 2 angles on the arc (20 degrees and 40 degrees from the base of the turntable) with an image overlap of 15 degrees, controlled by a stepper motor. Ear 1 was placed on the turntable and captured 5 times with smartphone 1 and tested for precision. Then, ears 1 to 6 were scanned once with a laser scanner and with smartphones 1 and 2. The images were converted into 3D casts and compared for accuracy against their laser scanned counterparts for surface area, volume, interpoint mismatches, and spatial overlap. Acceptability thresholds were set at 0.70 for spatial overlap. Results The test for smartphone precision in comparison with that of the laser scanner showed a difference in surface area of 774.22 ±295.27 mm2 (6.9% less area) and in volume of 4228.60 ±2276.89 mm3 (13.4% more volume). Both acceptability thresholds were also met. The test for accuracy among smartphones 1, 2, and the laser scanner showed no statistically significant differences (P>.05) in all 4 parameters among the groups while also meeting both acceptability thresholds. Conclusions Smartphone cameras used to capture 48 overlapping gypsum cast ear images in a controlled environment generated 3D models parametrically similar to those produced by standard laser scanners.

The topics of sub-specialization and regionalization of care have garnered increased attention among pediatric surgeons. Thyroid surgeries are one such sub-specialty and are commonly concentrated within practices. A national survey was conducted examining current surgeon practices and beliefs surrounding pediatric thyroid surgery.Non-resident members of the American Pediatric Surgical Association (APSA) were surveyed in October 2020. Respondents were stratified based on self-reported thyroid surgical experience. Those who performed thyroid surgery were asked about surgical technique and operative practices; those who did not were asked about referral patterns. All respondents were asked about perceptions surrounding the volume-outcome relationship for pediatric thyroid surgery.Among 1015 APSA members, 405 (40%) responded, with 79% (317/400) practicing at academic hospitals, 58% (232/401) practicing in major metropolitan area, and 41% (161/392) with over 10 years of attending pediatric surgery experience. Most respondents (88%, n = 356) agreed that thyroid surgery volume affects outcome, though wide variation was reported in the annual case threshold for "high volume" surgery. Eighty-four respondents (21%) reported performing ≥ 1 pediatric thyroid surgery in the past year. Of these, 82% routinely use recurrent laryngeal nerve monitoring, 32% routinely send hemithyroidectomy patients home the same day, and there was little consensus surrounding postoperative hypocalcemia management. The majority of respondents endorse performing thyroid procedures with a colleague.Pediatric thyroid surgery appears to be performed by a subset of active pediatric surgeons, most of whom endorse the use of a dual operating team. More evidence is needed to build consensus around additional perioperative practices.

Objective : To evaluate, by means of cone beam computed tomography (CBCT), the volume change of maxillary sinuses in patients that underwent orthodontic maxillary posterior en masse intrusion anchored with miniplates. Materials and Methods : The sample consisted of pretreatment (T1) and posttreatment (T2) CBCT scans obtained from 14 patients (4 male and 10 female), with a mean age of 32.4 years, that underwent orthodontic maxillary posterior en masse intrusion anchored with miniplates in the zygomatic crest. The mean treatment duration was 20 months and the mean intrusion movement was 2.4 mm. Maxillary sinus volume was measured by means of the software ITK SNAP (version 3.8.0) in T1 and T2 CBCT scans. The changes in sinuses volume were calculated by T1-T2 values. Data were analyzed statistically with Wilcoxon test at 5% of level of significance and the method error was analyzed with Wilcoxon test, intraclass correlation and Dahlberg's formula. Results : The mean difference (T1-T2) was -242.85 mm³ (p = 0.396) for the right sinus and -32.5 mm³ (p = 0.875) for the left sinus. A slight increase in the volume of the sinuses was shown although these results were not statistically significant. Conclusion : The orthodontic maxillary posterior en masse intrusion anchored with miniplates did not influence significantly the maxillary sinus volume.

In this paper, a new data augmentation algorithm, named Mask2Defect is proposed. Via prior knowledge based data infusing, this method is able to generate defects with varied features. Large volume of defects with different shapes, severities, scales, rotation angles, spatial locations, and part numbers can be generated in a controllable manner. These generated defects will work as teacher samples to fine-tune the inspection model, and automatically adapt it to a wider range of defects. To be specific, we first encode the prior knowledge into the teacher mask via the Industrial Prior Knowledge Encoder, and render the defect details according to the mask with the Mask-to-Defect Construction Network. Then, the Fake-to-Real Domain Transformation GAN is used to transform the rendered samples from the fake domain into the real defect domain. Experiments reveal that the synthesized image quality of our method outperforms the state-of-the-art generative methods, and the performance of the inspection model in defect classification and localization has also been improved by fine-tuned with the generated samples.

BACKGROUND: Addressing intensity inhomogeneity is critical in magnetic resonance imaging (MRI) because associated errors can adversely affect post-processing and quantitative analysis of images (i.e., segmentation, registration, etc.), as well as the accuracy of clinical diagnosis. Although several prior methods have been proposed to eliminate or correct intensity inhomogeneity, some significant disadvantages have remained, including alteration of tissue contrast, poor reliability and robustness of algorithms, and prolonged acquisition time. OBJECTIVE: In this study, we propose an intensity inhomogeneity correction method based on volume and surface coils simultaneous reception (VSSR). METHODS: The VSSR method comprises of two major steps: 1) simultaneous image acquisition from both volume and surface coils and 2) denoising of volume coil images and polynomial surface fitting of bias field. Extensive in vivo experiments were performed considering various anatomical structures, acquisition sequences, imaging resolutions, and orientations. In terms of correction performance, the proposed VSSR method was comparatively evaluated against several popular methods, including multiplicative intrinsic component optimization and improved nonparametric nonuniform intensity normalization bias correction methods. RESULTS: Experimental results show that VSSR is more robust and reliable and does not require prolonged acquisition time with the volume coil. CONCLUSION: The VSSR may be considered suitable for general implementation.

Due to the huge volume of point cloud data, storing and transmitting it is currently difficult and expensive in autonomous driving. Learning from the high-efficiency video coding (HEVC) framework, we propose a novel compression scheme for large-scale point cloud sequences, in which several techniques have been developed to remove the spatial and temporal redundancy. The proposed strategy consists mainly of three parts: intracoding, intercoding, and residual data coding. For intracoding, inspired by the depth modeling modes (DMMs), in 3-D HEVC (3-D-HEVC), a cluster-based prediction method is proposed to remove the spatial redundancy. For intercoding, a point cloud registration algorithm is utilized to transform two adjacent point clouds into the same coordinate system. By calculating the residual map of their corresponding depth image, the temporal redundancy can be removed. Finally, the residual data are compressed either by lossless or lossy methods. Our approach can deal with multiple types of point cloud data, from simple to more complex. The lossless method can compress the point cloud data to 3.63% of its original size by intracoding and 2.99% by intercoding without distance distortion. Experiments on the KITTI dataset also demonstrate that our method yields better performance compared with recent well-known methods.

Test costs for large industrial designs increase rapidly in recent years. On-chip test compression hardware has become a pragmatic technology to cut down the overall test costs by reducing test data volume. Determining the input and output channel counts of test compression hardware that results in minimum test data volume is thus a critical issue. In this paper, efficient methods to estimate test pattern counts for an extensive range of input/output counts are developed. These methods require only a small number of ATPG runs. The estimation results can then be utilized to determine the test data volume for each input/output configuration. The configuration with the estimated lowest test data volume thus can be determined. The pattern count results of each configuration for a design can also be used to determine the best suitable configuration when the design is to be embedded in an SoC system.

Objectives This study aimed to determine the correlation between alveolar cleft volume and fenestration and dehiscence in the adjacent alveolar bone in patients with unilateral cleft lip and palate (UCLP) using cone-beam computed tomography (CBCT) sections. Materials and methods In this descriptive, cross-sectional study, CBCT scans of 68 non-syndromic patients with UCLP aged between 6 and14 years were selected. All patients were treated in Iran and had undergone lip and palate repair surgery within the first 3 to 18 months after birth. CBCT scans had been taken after orthodontic expansion and prior to alveolar bone grafting surgery. Cleft volume, fenestration and dehiscence were assessed using Mimics software. Data were analyzed using independent t-test, Kruskal-Wallis test, Spearman's correlation coefficient and logistic regression model. Results The mean alveolar cleft volume was 628.66±172.84 mm3. There was a significant negative correlation between cleft volume and fenestration (P Conclusion The Mimics software can be successfully used to estimate the cleft volume prior to surgical procedures in UCLP patients. The results suggest that the alveolar cleft volume can be used as an aid to assess the periodontal condition of adjacent teeth. The cleft volume has a negative and positive correlation with fenestration and dehiscence respectively.

Background The association between volume and outcomes has led to recommendations that patients undergo surgery at high-volume centers. We aimed to determine if older patients with rectal cancer are undergoing operations at high-volume centers. Methods We identified patients ≥50 years old who underwent rectal cancer resection using the NCDB (2004–2015). Tertiles were used to categorize facility volume and distance traveled. Results Higher facility volume was associated with improved outcomes. Patients >75 years old were less likely than patients 50–59 years old to be treated at high-volume centers. Traveling >16.8 miles was associated with treatment at high-volume facilities, however patients >75 years old were less likely to travel >16.8 miles. Conclusions Higher facility volume is associated with improved outcomes after rectal cancer resection. However, older patients are less likely to be treated at high-volume facilities. Older patients travel shorter distances for care, suggesting that care integration across networks must be optimized.

We present a user-initialized, automated segmentation method for use with echocardiograms (echo). The method uses an iterative Dijkstra's algorithm, a strategic node selection, and a novel cost matrix formulation based on intensity peak prominence, termed the Prominence Iterative Dijkstras algorithm, or ProID. ProID is initialized with three user-input clicks per time-series scan. ProID was tested using artificial echo images representing five different systems. Results showed accurate LV contours and volume estimations as compared to the ground-truth for all systems. Using the CAMUS dataset, we demonstrate ProID maintained similar Dice similarity scores to other automated methods. ProID was then used to analyze a clinical cohort of 66 pediatric patients, including normal and diseased hearts. Output segmentations, end-diastolic, end-systolic volumes, and ejection fraction were compared against manual segmentations from two expert readers. ProID maintained an average Dice score of 0.93 when comparing against manual segmentation. Comparing the two expert readers, the manual segmentations maintained a score of 0.93 which increased to 0.95 when they used ProID. Thus, ProID reduced the inter-operator variability across the expert readers. Overall, this work demonstrates ProID yields accurate boundaries across age groups, disease states, and echo platforms with low computational cost and no need for training data.

Owing to the inefficiency to hide large volume of secret data for the reversible data hiding (RDH) image steganography approaches, we propose two improved RDH based approaches, such as (1) improved dual image based least significant bit (LSB) matching with reversibility, and (2) n-rightmost bit replacement (n-RBR) and modified pixel value differencing (MPVD). The first approach extends the ability of LSB matching with reversibility using dual images. Whereas the second approach utilizes four identical cover images for secret data embedding using two phases, such as (1) n-rightmost bit replacement (n-RBR) and (2) modified pixel value differencing (MPVD). In the n-RBR phase, n bits of secret data are embedded in the pair of two neighboring pixels of the first two identical images, where 1 ≤ n ≤ 4. Correspondingly, the MPVD phase uses the third and fourth identical images for hiding the secret data. Experimental results with respect to peak signal-to-noise ratio (PSNR), embedding capacity (EC), structural similarity index (SSIM), and the comparative analysis with recently proposed state-of-art approaches exhibit the superiority of the proposed approach. Besides reversibility, the proposed approach ensures high fidelity to salt and pepper (S&P) noise, RS analysis, and pixel difference histogram (PDH) analysis.

Background Given the complexity of living donor hepatectomy, it is expected that high hospital volume will better outcomes. This study aims to evaluate post-operative outcomes for living donor hepatectomy in a medium volume liver transplant centre and compare to outcomes in high volume centres. Also, it serves as a validation tool for framework of structure-process-outcome model for safe living donor hepatectomy program. Methods 204 donors who underwent donor hepatectomy between June 1996 to September 2019 were reviewed retrospectively and compared to outcomes in high volume centres. Results At 6 months, overall donor morbidity rate was 20/204 (9.8%). Wound complications were most common at 5/204 (2.5%). Majority of complications were either Clavien grade 1 or 2 and only 3 donors had Clavien grade 3 complications. There was zero donor mortality. Discussion Our centre's donor morbidity rate of 9.8% is the one of the lowest reported in the published literature. With increased experience, stringent donor selection and enhanced perioperative care by a multi-disciplinary team, outcomes in a medium volume centre can match the outcomes reported in high volume centres. The framework for quality in terms of structure, process and outcomes is presented which can be adopted for developing programs.

Introduction This study aims to define the impact that the novel Coronavirus Disease 2019 (COVID-19) pandemic has had on the volume of common plastic and reconstructive procedures. Methods TrinetX is a national, federated database that was utilitzed in surveying plastic and reconstructive procedural volumes among 53 Healthcare organizations (HCO) between March 2018 and May 2021. This timeframe was divided into pre-pandemic (March 2018 to February 2020) and pandemic periods (March 2020 to May 2021). Each period was then sub-divided into the four seasons of the year and mean monthly procedural volume per HCO was compared. A student's t-tests comparing pre-pandemic and pandemic seasonal mean procedural volumes were used for statistical analysis. Results A total of 366,032 patient encounters among 53 HCO were included. The average seasonal volume per HCO of all procedures decreased from 872.11 procedures during pre-pandemic seasons to 827.36 during pandemic seasons. Spring 2020 volumes declined for most procedures as 15 of 24 (63%) assessed procedure categories experienced statistically significant decreases. Spring 2021 experienced rebounds with 15 of 24 (63%) assessed procedures showing statistically significant increases. Conclusion During the pandemic period, the average procedural volume per HCO of 14 procedure categories was significantly less than the pre-pandemic average procedural volume. As a whole, there was a inverse relationship between new United States COVID-19 cases and plastic and reconstructive surgery procedure volumes.

Background: Manual segment target volumes were time-consuming and inter-observer variability couldn’t be avoided. With the development of computer science, auto-segmentation had the potential to solve this problem. Objective: To evaluate the accuracy and stability of Atlas-based and deep-learning-based auto-segmentation of the intermediate risk clinical target volume, composed of CTV2 and CTVnd, for nasopharyngeal carcinoma quantitatively. Methods and Materials: A cascade-deep-residual neural network was constructed to automatically segment CTV2 and CTVnd by deep learning method. Meanwhile, a commercially available software was used to automatically segment the same regions by Atlas-based method. The datasets included contrast computed tomography scans from 102 patients. For each patient, the two regions were manually delineated by one experienced physician. The similarity between the two auto-segmentation methods was quantitatively evaluated by Dice similarity coefficient, the 95th Hausdorff distance, volume overlap error and relative volume difference, respectively. Statistical analyses were performed using the ranked Wilcoxon test. Results: The average Dice similarity coefficient (±standard deviation) given by the deep-learning- based and Atlas-based auto-segmentation were 0.84(±0.03) and 0.74(±0.04) for CTV2, 0.79(±0.02) and 0.68(±0.03) for CTVnd, respectively. For the 95th Hausdorff distance, the corresponding values were 6.30±3.55 mm and 9.34±3.39 mm for CTV2, 7.09±2.27 mm and 14.33±3.98 mm for CTVnd. Besides, volume overlap error and relative volume difference could also predict the same situations. Statistical analyses showed significant difference between the two auto-segmentation methods (p Conclusions: Compared with the Atlas-based segmentation approach, the deep-learning-based segmentation method performed better both in accuracy and stability for meaningful anatomical areas other than organs at risk.

BACKGROUND: When assessing the volume of pulmonary nodules on computed tomography (CT) images, there is an inevitable discrepancy between values based on the diameter-based volume calculation and the voxel-counting method, which is derived from the Euclidean distance measurement method on pixel/voxel-based digital image. We aimed to evaluate the ability of a modified diameter measurement method to reduce the discrepancy, and we determined a conversion equation to equate volumes derived from different methods. METHODS: Two different anthropomorphic phantoms with subsolid and solid nodules were repeatedly scanned under various settings. Nodules in CT images were detected and segmented using a fully automated algorithm and the volume was calculated using three methods: the voxel-counting method (V(vc)), diameter-based volume calculation (V(d)), and a modified diameter-based volume calculation (V(d+)(1)), in which one pixel spacing was added to the diameters in the three axes (x-, y-, and z-axis). For each nodule, V(d) and V(d)(+1) were compared to V(vc) by computing the absolute percentage error (APE) as follows: APE =100 × (V – V(vc))/V(vc). Comparisons between APE(d) and APE(d+1) according to CT parameter setting were performed using the Wilcoxon signed-rank test. The Jonckheere-Terpstra test was used to evaluate trends across the four different nodule sizes. RESULTS: The deep learning-based computer-aided diagnosis (DL-CAD) successfully detected and segmented all nodules in a fully automatic manner. The APE was significantly less with V(d+1) than with V(d) (Wilcoxon signed-rank test, P

PURPOSE To investigate the volumetric facial soft tissue changes associated with wearing complete dentures using 3D face scans. MATERIALS AND METHODS Forty volunteers, 20 men and 20 women, were recruited for the study and treated with maxillary and mandibular complete dentures. Six facial scans were taken of each subject. Three scans were wearing a complete denture, and three without them. The 3D face scans were captured with the volunteers in three mouth positions: closed, relaxed, and smiling. Each scan was superimposed in order to analyze and quantify the linear measurements of 14 soft tissue landmarks and the total volume that the subject gained with the prosthesis. RESULTS Three variables were evaluated in each analysis: gender, mouth attitude, and age category. In the analysis of the soft tissue landmarks, there was a significant effect of age, with patients older than 75 years showing the greatest changes (P < .05). The landmarks that showed the most changes were those located around the mouth. In the volume analysis, the variable with the highest influence was gender, with men gaining more volume than women (P < .05). CONCLUSION Complete dentures have a significant effect on volumetric change in perioral tissues. These changes are marked in patients older than 75 years. Compared to women, men depicted greater volumetric changes with complete dentures. These results open a new avenue for clinicians and developers using face scans to design future restorations for edentulous patients.

This paper proposes a new method to reduce CT (computed tomography) artifacts by using multiple X-ray CT scanning in which CT data fusion is combined with optimized selection of a combination of scan angles. Industrial X-ray CT has been widely used for investigating industrial parts including metals, which cause various CT artifacts. These CT artifacts reduce the quality of X-ray CT images, and prevent precise measurements. Our multiple X-ray CT scanning approach focuses on CT artifacts distribution estimation, which including scan angle combination optimization, multiple CT volume registration, and CT volume fusion. To demonstrate our method, we selected multiple optimal scan angles and conducted volume fusion on industrial parts included metals and resins. Our approach effectively reduced CT artifacts. Our experiments also showed that additional scans successively reduced metal artifacts in various regions, suggesting that our scan angle selection method successfully selected an optimal combination of scan angles.

The emergence of 3D point clouds (3DPCs) is promoting the rapid development of immersive communication, autonomous driving, and so on. Due to the huge data volume, the compression of 3DPCs is becoming more and more attractive. We propose a novel and efficient color attribute compression method for static 3DPCs. First, a 3DPC is partitioned into several sub-point clouds by color distribution analysis. Each sub-point cloud is then decomposed into a lot of 3D blocks by an improved k-d tree-based decomposition algorithm. Afterwards, a novel virtual adaptive sampling-based sparse representation strategy is proposed for each 3D block to remove the redundancy among points, in which the bases of the graph transform (GT) and the discrete cosine transform (DCT) are used as candidates of the complete dictionary. Experimental results over 10 common 3DPCs demonstrate that the proposed method can achieve superior or comparable coding performance when compared with the current state-of-the-art methods.

Characterization of Peyronie’s disease (PD) involves manual goniometry and penile length measurement. These techniques neglect volume loss or hourglass deformities. Inter-provider variability complicates accuracy. Using 3D-printed models, we aimed to evaluate measurement accuracy and variability and establish computational assessment workflows. Five digital phantoms were created: 13.0 cm cylinder, 13.0 cm hourglass cylinder, 15.0 cm cylinder with 40° angulation, 12.0 cm straight penis, and 12.9 cm PD penis with 68° angulation and hourglass. Lengths, volumes, and angles were determined computationally. Each phantom was 3D-printed. Ten urology providers determined lengths, angles, and volumes with measuring tape, goniometer, and volume calculator. Provider versus computational measurements were compared to determine accuracy using t-tests or Wilcoxon rank-sum tests. No significant differences were observed between manual assessment of length of penile models and designed length in penile models. Average curvature angles from providers for bent cylinder and PD phantoms were 38.3° ± 3.9° (p = 0.25) and 57.5° ± 7.2° (p = 0.006), respectively. When assessing for volume, hourglass cylinder and bent cylinder showed significant differences between designed volume and provider averages. All assessments of length, angle, and volume showed significant provider variability. Our results suggest manual measurements suffer from inaccuracy and variability. Computational workflows are useful for improved accuracy and volume assessment.

Urinary bladder volume monitoring can benefit from contactless measurements, as alternative to the traditional medical methods of transurethral catheterization or ultrasound examination. The emerging modality of Magnetic Induction Tomography (MIT) offers the possibility for estimation of the intravesical volume in the physiological and pathological states using conductivity map reconstructions of the tissues present in the pelvic region. Within MIT, eddy currents originating from the conductive urine can produce their own magnetic field in response to an external magnetic source that is susceptible of being detected outside the body by means of a static ring of sensing coils. However, the ill-conditioned and ill-posed nature of the MIT Inverse Problem make the numerical implementation and conductivity estimation highly laborious. In this paper, we present a rotational frame model based on the MIT principles with application in urodynamic studies, which allows to extend the number of contactless measurements without increasing the overall dimension of the simulation domain, at the expense of solving multiple MIT Forward Problems. On the inversion process, the single-step Gauss-Newton method with Laplacian regularizer is recruited to estimate the bladder volume non-invasively and remotely (estimation error of 19%) using a simplified (quasi 2D) approximation to the distribution of eddy currents in the examined region, therefore paving the way for this technique to surpass the current limitations found in intravesical volume monitoring.

Three-dimensional ultrasound (US) of abdominal aortic aneurysms (AAAs) is limited by the field-of-view of the 3D-US transducer. To obtain an extended field-of-view (XFoV), two transducer navigation system-assisted US protocols have been developed: XFoV-2D and XFoV-3D. In this study, the XFoV US protocols were compared with the currently available 3D-US protocol with standard field-of-view (FoV-st) and the established gold standard, computed tomography angiography (CTA). A total of 65 patients with AAA were included, and AAA imaging was processed offline with prototype software. The novel XFoV-2D and XFoV-3D protocols allowed for assessment of full AAA volume in significantly more patients (45/65 [69%] and 43/65 [66%], respectively), compared with the current 3D-US standard, FoV-st (30/65 [46%] patients). The mean difference in AAA volume estimation between each XFoV US protocol and 3-D CTA differed significantly (XFoV-2D: 16.9 mL, XFoV-3D: 7.6 mL, p = 0.002), indicating that XFoV-3D agreed best with 3D-CTA. No significant difference was found in the variance of full AAA volume quantification between each XFoV US protocol and CTA (p = 0.49). It is concluded that the XFoV US protocols improved the generation of full AAA volumes compared with the currently available 3D-US technology, with AAA volume estimates comparable to CTA estimates.

Objective: The aim of this study is to investigate the effect of complex decongestive physiotherapy (CDP) plus intermittent pneumatic compression (IPC) applications on upper extremity circumference and volume in patients with lipedema. Methods and Results: All participants included in the study were included in a treatment protocol consisting of CDP and IPC. The Perometer 400 NT was used in the measurement of upper extremity volume and circumference before and after treatment. The measurements were performed in four reference points. According to the Perometer results before and after CDP, statistically significant reduction was found in the circumference of 3 of the 4 points of measurements performed in each of the left and right upper extremities. When the volume assessments were compared, it was seen that statistically significant reduction was found in the volume of both limbs. Conclusion: A treatment program consisting of CDP and IPC can be effective in reducing the circumference and volume of the arm in patients with upper extremity lipedema. So, CDP applications can help prevent the development of complications such as lipolymphedema, hypertension, and heart failure. Clinical Trial Registration number: NCT04643392 https://register.clinicaltrials.gov/prs/app/action/SelectProtocol?sid=S000AF9B&selectaction=Edit&uid=U00055NT&ts=2&cx=-3oevdw.

The Weather Surveillance Radar-1988 Doppler (WSR-88D) network has undergone several improvements in the last decade with the upgrade to dual-polarization capabilities and the ability for forecasters to rescan the lowest levels of the atmosphere more frequently through the use of Supplemental Adaptive Intra-volume Scanning (SAILS). SAILS reduces the revisit period for scanning the lowest 1 km of the atmosphere but comes at the cost of a longer delay between scans at higher altitudes. This study quantifies how often radar volume coverage patterns (VCPs) and all available SAILS options are used during the issuance of 148 882 severe thunderstorm and 18 263 tornado warnings, and near 10 474 tornado, 58 934 hail, and 127 575 wind reports in the dual-polarization radar era. A large majority of warnings and storm reports were measured with a VCP providing denser low-level sampling coverage. More frequent low-level updates were employed near tornado warnings and reports compared to severe thunderstorm warnings and hail or wind hazards. Warnings issued near a radar providing three extra low-level scans (SAILSx3) were more likely to be verified by a hazard with a positive lead time than warnings with fewer low-level scans. However, extra low-level scans were more frequently used in environments supporting organized convection as shown using watches issued by the Storm Prediction Center. In recent years, the number of midlevel radar elevation scans is declining per hour, which can adversely affect the tracking of convective polarimetric signatures, like ZDR columns, which were found above the lowest elevation angle in over 99% of cases examined.

Background: Lymphedema (LE) is a significant clinical problem for breast cancer survivors. While the water displacement test and circumferential assessment using a tape measure (TM) are common methods to assess differences in arm volumes, faster and more reliable methods are needed. Study purposes, in breast cancer survivors (n = 294), were to compare the average total arm volumes and interlimb volume ratios for women with and without a history of LE, using a TM and three-dimensional (3D), whole-body surface scanner (3D scan); compare the level of agreement between arm volumes and interlimb volume ratios obtained using the two devices; and evaluate the percent agreement between the two measures in classifying cases of LE using three accepted thresholds. Methods and Results: Measurements were done using a spring-loaded TM and Fit3D ProScanner. Paired t-tests and Bland-Altman analyses were used to achieve the study aims. For circumference and volume comparisons, compared with the 3D scan, values obtained using the TM were consistently smaller. In terms of level of agreement, the Bland-Altman analyses demonstrated large biases and wide limits of agreement for the calculated arm volumes and volume ratios. In terms of the classification of caseness, using the 200-mL interlimb volume difference criterion resulted in 81.6% overall agreement; using the >10% volume difference between the affected and unaffected arms resulted in 78.5% overall agreement; and using the volume ratio ≥1.04 criterion resulted in 62.5% overall agreement. For all three accepted threshold criteria, the percentage of cases was significantly different between the TM and 3D scan techniques. Conclusions: The 3D technology evaluated in this study has the potential to be used for self-initiated surveillance for LE. With improvements in landmark identification and software modifications, it is possible that accurate and reliable total arm volumes can be calculated and used for early detection.

Modern advanced phasor measurement units are developed with ultrahigh reporting rates to meet the demand for monitoring the power systems dynamics in detail. Due to the large volume of data, the communication and storage systems are seriously challenged with the presence of ultrahigh-density (UHD) synchrophasor and point-on-wave (POW) data. Therefore, it is an urgent task to compress the UHD data for more efficient communication and data storage. This article proposes several methods to compress the synchrophasor and POW data in a lossless manner. First, an improved time-series special compression (ITSSC) method is proposed to compress the UHD frequency data. Second, a delta-difference Huffman method is combined with the time-series special compression algorithm to compress the UHD phase angle data. Finally, a cyclical high-order delta modulation method is proposed to compress the UHD POW data. The proposed models are extensively tested and compared with different existing lossless compression algorithms using the field-collected synchrophasor and POW data at different reporting rates. The results indicate that the proposed algorithms are efficient in performing lossless compression for the UHD synchrophasor and POW data in real time.

OBJECTIVE The optimal treatment paradigm for large arteriovenous malformations (AVMs) is controversial. One approach is volume-staged stereotactic radiosurgery (VS-SRS). The authors previously reported efficacy of VS-SRS for large AVMs in a multiinstitutional cohort; here they focus on risk of symptomatic adverse radiation effects (AREs). METHODS This is a multicentered retrospective review of patients treated with a planned prospective volume staging approach to stereotactically treat the entire nidus of an AVM, with volume stages separated by intervals of 3–6 months. A total of 9 radiosurgical centers treated 257 patients with VS-SRS between 1991 and 2016. The authors evaluated permanent, transient, and total ARE events that were symptomatic. RESULTS Patients received 2–4 total volume stages. The median age was 33 years at the time of the first SRS volume stage, and the median follow-up was 5.7 years after VS-SRS. The median total AVM nidus volume was 23.25 cm3 (range 7.7–94.4 cm3), with a median margin dose per stage of 17 Gy (range 12–20 Gy). A total of 64 patients (25%) experienced an ARE, of which 19 were permanent. Rather than volume, maximal linear dimension in the Z (craniocaudal) dimension was associated with toxicity; a threshold length of 3.28 cm was associated with an ARE, with a 72.5% sensitivity and a 58.3% specificity. In addition, parietal lobe involvement for superficial lesions and temporal lobe involvement for deep lesions were associated with an ARE. CONCLUSIONS Size remains the dominant predictor of toxicity following SRS, but overall rates of AREs were lower than anticipated based on baseline features, suggesting that dose and size were relatively dissociated through volume staging. Further techniques need to be assessed to optimize outcomes.

In this study, a maximum volume sampling model is proposed to improve the accuracy and efficiency of reliability computation. An ellipsoid is constructed with the maximum volume approach in a safe domain, and a new maximum volume optimization method is proposed. The sampling model only computes the samples outside the ellipsoid, which considerably enhances computational efficiency. Furthermore, the uniform sampling strategy and Givens transformation are adopted to efficiently solve the maximum volume optimization model. A series system example, a three-dimensional rock slope example, and an arch bridge example are tested to verify the validity of the proposed maximum volume sampling model. The results indicate that the maximum volume sampling model displays high accuracy and efficiency.

Classification algorithms face difficulties when one or more classes have limited training data. We are particularly interested in classification trees, due to their interpretability and flexibilit...

In this paper we study numerically and experimentally non-reversible deformation of anisotropic, semi-flexible fibre networks. We formulate a Discrete Element Model (DEM) with bonded particles to simulate uniaxial compression of such networks and use this model to describe and quantify the effect of elasto-plastic fibre contacts and fibre-fibre adhesion on non-reversible deformation. Our results show that inter-fibre adhesion plays a role for compression in a low solid volume fraction range where adhesive forces can overcome fibre deformation forces and moments. Also, elasto-plastic contacts between fibres become important at higher solid volume fractions when the yield criterion is exceeded. The combined case of fibres having elasto-plastic contacts and adhesion shows a significant synergetic effect leading to a degree of non-reversible deformation of the network far beyond that of networks with only elasto-plastic fibre contacts or inter-fibre adhesion.

A new correction method for laser Doppler velocimetry (LDV) measurement volume effects on the time-averaged velocity statistics is proposed by considering the probability density function of streamwise fluctuating velocity and the streamwise cross-sectional area of the measurement volume. The proposed correction method is fundamentally different from previous correction methods using a laser intensity profile of LDV. We propose a simple equation to correct the measurement volume effects. By using the equation and calculating both measurement locations and volumes precisely, the correction for the measurement volume effects on time-averaged velocity statistics can be performed on the basis of LDV measurement data. By comparing with the correction method proposed by Durst et al. (1995), the two correction methods provide almost the same results. In addition, the validity and applicability to high Reynolds numbers or low spatial resolution conditions of the two correction methods are confirmed.

PURPOSE To investigate the accuracy of a segment-counting method in predicting lung function and volume after stapler-based thoracoscopic segmentectomy in comparison with lobectomy. METHODS Between 2014 and 2018, patients who underwent these procedures were retrospectively reviewed. Thoracic computed tomography and spirometry data before and 1 year after the surgery were assessed. We evaluated the differences between the predicted values using a segment-counting method and the actual postoperative values for lung function and volume in each group. Sub-analyses were also performed to assess the impact of the number of staples and resected segments in predicting patient outcomes. RESULTS We included 116 patients (segmentectomy, 69; lobectomy, 47). Actual postoperative lung function and volume values matched the predicted values in the stapler-based segmentectomy group, and significantly exceeded the predictions in the lobectomy group (P

Background Studies of the hospital volume-outcome relationship have highlighted that a greater volume activity improves patient outcomes. While this finding has been known for years, most studies to date have failed to delve into what underlies this relationship. Objective This study aimed to shed light on the basis of the hospital volume effect on patient outcomes by comparing treatment modalities for epithelial ovarian carcinoma patients. Data An exhaustive dataset of 355 patients in first-line treatment for Epithelial Ovarian Carcinoma (EOC) in 2012 in three regions of France was used. These regions account for 15% of the metropolitan French population. Methods In the presence of endogeneity induced by a reverse causality between hospital volume and patient outcomes, we used an instrumental variable approach. Hospital volume of activity was instrumented by the distance from patients’ homes to their hospital, the population density, and the median net income of patient municipalities. Results Based on our parameter estimates, we found that the rate of complete tumor resection would increase by 15.5 percentage points with centralized care, and by 8.3 percentage points if treatment decisions were coordinated by high-volume centers compared to decentralized care. Conclusion As volume alone is an imperfect correlate of quality, policy-makers need to know what volume is a proxy for in order to devise volume-based policies.

This document presents a simulation-based method for the polyhedra packing problem (PPP). This problem refers to packing a set of irregular polyhedra (convex and concave) into a cuboid with the objective of minimizing the cuboid’s volume, considering non-overlapping and containment constraints. The PPP has applications in additive manufacturing and packing situations where volume is at a premium. The proposed approach uses Unity® as the simulation environment and considers nine intensification and two diversification movements. The intensification movements induce the items within the cuboid to form packing patterns allowing the cuboid to decrease its size with the help of gravity-like accelerations. On the other hand, the diversification movements are classic transition operators such as removal and filling of pieces and enlargement of the container, which allow searching on different solution neighborhoods. All simulated movements were hybridized with a probabilistic tabu search. The proposed methodology (with and without the hybridization) was compared by benchmarking with all previous works solving the PPP with irregular items. Results show that satisfactory solutions were reached in a short time; even a few published results were improved.

The digitisation of heritage is being rapidly realised in many parts of the world thanks to LiDAR technology. In addition to the simple digital preservation of heritage, 3D acquisition makes it possible to monitor the structural condition and assess possible damage. This paper presents a method for modelling the lost volume of a heritage bridge. The selected case study is the Fillaboa bridge, in Salvaterra de Miño, Spain, which has two cutwaters with the same cutting angle, one of which is damaged and has a stone loss. The bridge was acquired with a Terrestrial Laser Scanner. The method consists of the following processes. First, the walls of the whole cutwater are segmented and aligned by Iterative Closest Point algorithm over the damaged cutwater. Second, the distance between the two point clouds is calculated and the damaged area is delimited in both point clouds. And third, the alpha shape algorithm is applied to model the point cloud of the damaged area to a polygon. By searching for the optimal alpha radius, the polygon that best fits the damaged volume is generated. The proposed method also allows digital reconstruction of the damaged area, although it is sensitive to acquisition problems, which require manual interventions in the processing. The accuracy of the method is mainly dependent on the acquired point cloud registration (with an RMS error of 60mm) and the ICP registration error (31mm). Its use is limited to the existence of two geometries that allow superposition: one in good condition and one damaged to compare.

This study aims to investigate the relationship of the persistence of metopic suture (PMS), frontal sinus volume (FSV), and olfactory fossa depth (OFD).Tomography scans of 1,603 patients aged 18-65 years were evaluated for the presence of PMS. In the study, 74 PMS cases and 74 controls were included. The appearance of each individual's frontal sinus was classified as aplasia, hypoplasia, or normal. Two observers independently measured the lateral lamella length (LLL), OFD, and FSV. Interobserver agreement was evaluated with the intraclass correlation coefficient (ICC) and Cohen's kappa coefficient (κ).The prevalence of PMS was found to be 4.99% [95% confidence interval (CI): 4.03-6.17]. The PMS group had five times higher hypoplasia/aplasia than the controls (52.70%, 95% CI: 41.48-63.66 and 10.81%, 95% CI: 5.58-19.91, respectively; p0.001). An "almost perfect" agreement was detected among observers for the frontal sinus appearance classification: κ=0.807, p0.001. The ICC of continuous measurements for OFD, LLL, and FSV, respectively, presented "excellent" reliability: 0.956, 0.958, and 0.981, with p0.001 for each. LLL was shorter, OFD was shallower, and FSV was smaller in the PMS group than the control group (p0.001). There was a moderate positive correlation between OFD, LLL, and FSV (r=0.306, r=0.302).This study interprets that the presence of PMS is related frontal sinus development and volume. With PMS, a smaller FS, shorter lateral lamella, and shallower olfactory fossa may be expected.Bu çalışma, persistan metopik sütür (PMS) ile olfaktör fossa derinliği (OFD), ve frontal sinüs volümü (FSV) arasındaki ilişkiyi araştırmayı amaçlamaktadır.Yaşları 18-65 arasında değişen 1.603 hastanın tomografileri PMS varlığı açısından değerlendirildi. Yetmiş dört PMS olgusu ve 74 kontrol çalışmaya dahil edildi. Her bireyin frontal sinüs görünümü aplazi, hipoplazi veya normal olarak sınıflandırıldı. Lateral lamella uzunluğu (LLU), OFD ve FSV ölçümleri iki gözlemci tarafından bağımsız olarak yapıldı. Gözlemciler arası uyum değerlendirilirken, sürekli değişkenler için sınıf içi korelasyon katsayısı (ICC) ve Cohen’s kappa katsayısı (κ) kullanıldı.PMS prevalansı %4,99 [güven aralığı (GA) %95: 4,03-6,17] olarak bulundu. Hipoplazi/aplazi, PMS grubunda kontrol grubuna göre beş kat daha fazlaydı (sırasıyla %52,70; GA %95: 41,48-63,66 ve %10,81; GA %95: 5,58-19,91, p0,001). Frontal sinüs görünüm sınıflandırması için gözlemciler arasında “mükemmel” bir uyum tespit edildi: κ=0,807, p0,001. OFD, LLU ve FSV için ICC “mükemmel” güvenilirlik sundu: Her biri için sırasıyla 0,956, 0,958 ve 0,981 ve p0,001. PMS grubunda, LLU daha kısaydı, OFD daha sığdı ve FSV, kontrol grubuna göre daha küçüktü (her biri için p0,001). OFD, LLU ve FSV arasında orta derecede pozitif korelasyon vardı (r=0,306, r=0,302).Bu çalışmanın sonucunda, PMS’nin frontal sinüs gelişimi ve volümü ile ilişkili olduğu bulunmuştur. PMS varlığında daha küçük bir FS, daha kısa lateral lamella ve daha az derin olfaktör fossa beklenebilir.

Aim To assess the impact of the COVID-19 outbreak on trends in hospital admissions and number of diagnostic and therapeutic procedures in the largest tertiary vascular center in Hungary. Patients and Methods A retrospective analysis was carried out. The first wave of the COVID-19 pandemic occurred approximately from March 15 until June 1 in Hungary. We have compared the same period of 2020 to 2019. Electronic medical records were reviewed for the clinical status of the patients and treatment-related information. Results The total number of diagnostic angiographies and therapeutic interventions in 2020 (N = 233) decreased significantly (P = 0.046) compared to 2019 (N = 373). The ratio of Fontaine stage I–II cases to Fontaine stage III–IV cases for both diagnostic angiographies and therapeutic interventions was significantly lower (OR, 2.11; 95% CI, 1.26–3.59; P = 0.007 and OR, 3.22; 95% CI, 1.67–6.52; P < 0.001) in 2020 (0.36 and 0.27) than in 2019 (0.77 and 0.89). There was also a negative but not significant change in the number of supra-aortic (including internal carotid artery stenting) (P = 0.128) and other vascular therapeutic interventions (superior vena caval stenting, hemodialysis access percutaneous transluminal angioplasty [PTA], visceral artery/vein PTA/stenting, embolization) (P = 0.452) in 2020 (N = 16 and N = 21) compared to 2019 (N = 39 and N = 37). Conclusion The first wave of the COVID-19 pandemic had a negative effect on the total number of endovascular procedures in the largest tertiary vascular center in Hungary.