Does the intraoperative 3D-flat panel control of the planned implant position lead to an optimization and increased in safety in the anatomically demanding region C1/2?

BACKGROUND: The aim of this study was to evaluate the applicability and advantages of intraoperative imaging using a 3D flat panel in the treatment of C1/2 instabilities. MATERIALS: Prospective single-centered study including surgeries at the upper cervical spine between 06/2016 and 12/2018. Intraoperatively thin K-wires were placed under 2D fluoroscopic control. Then an intraoperative 3D-scan was carried out. The image quality was assessed based on a numeric analogue scale (NAS) from 0 to 10 (0 = worst quality, 10 = perfect quality) and the time for the 3D-scan was measured. Additionally, the wire positions were evaluated regarding malpositions. RESULTS: A total of 58 patients were included (33f, 25 m, average age 75.2 years, r.:18-95) with pathologies of C2: 45 type II fractures according to Anderson/D'Alonzo with or without arthrosis of C1/2, 2 Unhappy triad of C1/2 (Odontoid fracture Type II, anterior or posterior C1 arch-fracture, Arthrosis C1/2) 4 pathological fractures, 3 pseudarthroses, 3 instabilities of C1/2 because of rheumatoid arthritis, 1 C2 arch fracture). 36 patients were treated from anterior [29 AOTAF (combined anterior odontoid and transarticular C1/2 screw fixation), 6 lag screws, 1 cement augmented lag screw] and 22 patients from posterior (regarding to Goel/Harms). The median image quality was 8.2 (r.: 6-10). In 41 patients (70.7%) the image quality was 8 or higher and in none of the patients below 6. All of those 17 patients the image quality below 8 (NAS 7 = 16; 27.6%, NAS 6 = 1, 1.7%), had dental implants. A total of 148 wires were analyzed. 133 (89.9%) showed a correct positioning. In the other 15 (10.1%) cases a repositioning had to be done (n = 8; 5.4%) or it had to be drawn back (n = 7; 4.7%). A repositioning was possible in all cases. The implementation of an intraoperative 3D-Scan took an average of 267 s (r.: 232-310 s). No technical problems occurred. CONCLUSION: Intraoperative 3D imaging in the upper cervical spine is fast and easy to perform with sufficient image quality in all patients. Potential malposition of the primary screw canal can be detected by initial wire positioning before the Scan. The intraoperative correction was possible in all patients. Trial registration German Trials Register (Registered 10 August 2021, DRKS00026644-Trial registration: German Trials Register (Registered 10 August 2021, DRKS00026644- https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00026644 ).

A comparative evaluation of mechanical wear of adhesives used for bonded retainers that underwent brushing for 1 hour under 36 mm of linear action, using computer-aided 3D scan-an in vitro study.

OBJECTIVES: The aim of the present study was to comparatively evaluate the mechanical wear of adhesives used in bonded retainers. MATERIALS AND METHODS: Eighty mandibular acrylic teeth were included in the study that were divided into 4 different groups based upon the composite used. Each acrylic tooth was bonded with a retainer wire and composite of their respective group (Heliosit, Restofill, Tetric-N-flow, and Filtek Z350 XT). These bonded acrylic teeth were subjected to 3D scan in order to evaluate the volume and surface area of the composite. The 3D scans were recorded using MEDIT 3D scanner. After evaluating, the samples were subjected to brushing with the aid of a custom-made brushing simulator using a toothbrush with soft bristles and toothpaste slurry. The samples were subjected to 1 hr of brushing. These samples were again subjected to 3D scans to evaluate (post-test volume and surface area) and underwent statistical analysis. RESULTS: The results showed the Heliosit group exhibited the highest mean volume (1.76 mm3) and surface area (4.81 mm2) difference between the pre-test and post-test values whereas the least mean volume difference (1.10 mm3) and surface area difference (3.21 mm2) were seen in the Tetric-N-flow group. CONCLUSION: All the four composites underwent change in the mean surface area and volume after being subjected to brushing, suggesting that the composites routinely used for bonding fixed bonded lingual retainers are subjected to changes due to abrasion. The Heliosit group, which showed least filler loading among the 4 composites, exhibited least resistance to wear, whereas the Tetric-N-flow group which had highest filler loading among the composites exhibited highest resistance to wear. CLINICAL RELEVANCE: The most crucial phase during orthodontic treatment is the retention phase. This phase is responsible for the long-term results of the treatment. The retainers that are placed in the oral cavity are subjected to changes due to oral environment, chemical changes, and mechanical changes. These changes have a direct effect on the retainers, which tend to alter their properties. Thus, the effects of these changes are to be studied thoroughly.

Weathering Effects on Concrete Objects Based on 3D Scanned Examples and Geometric Features.

In this paper, we introduce a method for simulating the deformation of concrete surfaces due to weathering employing an example-based approach to replicate shape changes observed in real-world objects. A key challenge in implementing this approach is the scarcity of opportunities to measure shapes both before and after the weathering process. To overcome this limitation, we utilize concrete bricks collected from real-world environments as standardized examples, allowing for an analysis of erosion. By measuring erosion based on the estimated original shape, we correlate the characteristics of erosion with geometric features such as curvature and accessibility. We then apply this analysis to simulate new weathering effects in a given input model in alignment with its own geometric features. Our method yields visually compelling results while reproducing the variation of geometric weathering effects.

OptiFit: Computer-Vision-Based Smartphone Application to Measure the Foot from Images and 3D Scans.

The foot is a vital organ, as it stabilizes the impact forces between the human skeletal system and the ground. Hence, precise foot dimensions are essential not only for custom footwear design, but also for the clinical treatment of foot health. Most existing research on measuring foot dimensions depends on a heavy setup environment, which is costly and ineffective for daily use. In addition, there are several smartphone applications online, but they are not suitable for measuring the exact foot shape for custom footwear, both in clinical practice and public use. In this study, we designed and implemented computer-vision-based smartphone application OptiFit that provides the functionality to automatically measure the four essential dimensions (length, width, arch height, and instep girth) of a human foot from images and 3D scans. We present an instep girth measurement algorithm, and we used a pixel per metric algorithm for measurement; these algorithms were accordingly integrated with the application. Afterwards, we evaluated our application using 19 medical-grade silicon foot models (12 males and 7 females) from different age groups. Our experimental evaluation shows that OptiFit could measure the length, width, arch height, and instep girth with an accuracy of 95.23%, 96.54%, 89.14%, and 99.52%, respectively. A two-tailed paired t-test was conducted, and only the instep girth dimension showed a significant discrepancy between the manual measurement (MM) and the application-based measurement (AM). We developed a linear regression model to adjust the error. Further, we performed comparative analysis demonstrating that there were no significant errors between MM and AM, and the application offers satisfactory performance as a foot-measuring application. Unlike other applications, the iOS application we developed, OptiFit, fulfils the requirements to automatically measure the exact foot dimensions for individually fitted footwear. Therefore, the application can facilitate proper foot measurement and enhance awareness to prevent foot-related problems caused by inappropriate footwear.

Condition Monitoring of Railway Crossing Geometry via Measured and Simulated Track Responses.

This paper presents methods for continuous condition monitoring of railway switches and crossings (S&C, turnout) via sleeper-mounted accelerometers at the crossing transition. The methods are developed from concurrently measured sleeper accelerations and scanned crossing geometries from six in situ crossing panels. These measurements combined with a multi-body simulation (MBS) model with a structural track model and implemented scanned crossing geometries are used to derive the link between the crossing geometry condition and the resulting track excitation. From this analysis, a crossing condition indicator Cλ1-λ2, Î³ is proposed. The indicator is defined as the root mean square (RMS) of a track response signal γ that has been band-passed between frequencies corresponding to track deformation wavelength bounds of λ1 and λ2 for the vehicle passing speed (f = v/ λ). In this way, the indicator ignores the quasi-static track response with wavelengths predominantly above λ1 and targets the dynamic track response caused by the kinematic wheel-crossing interaction governed by the crossing geometry. For the studied crossing panels, the indicator C1-0.2 m, Î³ (λ1=1 and λ2=0.2) was evaluated for γ = u, v, or a as in displacements, velocities, and accelerations, respectively. It is shown that this condition indicator has a strong correlation with vertical wheel-rail contact forces that is sustained for various track conditions. Further, model calibrations were performed to measured sleeper displacements for the six investigated crossing panels. The calibrated models show (1) a good agreement between measured and simulated sleeper displacements for the lower frequency quasi-static track response and (2) improved agreement for the dynamic track response at higher frequencies. The calibration also improved the agreement between measurements and simulation for the crossing condition indicator demonstrating the value of model calibration for condition monitoring purposes.

Volumetry in Breast Reconstruction: Always New, Always Better?

Although breast surgeries for aesthetic or reconstructive purposes are regularly performed, no focus has been laid on establishing an adequate and reliable volumetry method. While CT and MRI scan represent methods that are already in clinical use, the 3D scan  is a novel and promising tool, easy to use with the possibility to measure the anatomic breast volume in an upright position. Nevertheless, its reliability is broadly underinvestigated. LEVEL OF EVIDENCE V : This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Three-Dimensional Analysis of Definitive Secondary Unilateral Cleft Rhinoplasty Using Cartilage Graft.

OBJECTIVE: Three-dimensional assessment of nasal morphology in patients with unilateral cleft lip nose treated by cartilage graft augmentation. DESIGN: Retrospective study. PATIENTS AND INTERVENTION: Thirteen patients with unilateral cleft lip nose underwent definitive secondary rhinoplasty and postsurgical changes were examined using a three-dimensional (3D) laser scan. MAIN OUTCOME MEASURE: Nasal dorsum length, nasal tip, alar width, and alar base width in frontal view; nasion depth, nasal tip projection, nasal dorsal angle, and nasal tip angle in lateral view; nostril width, nostril height, and nasal tip height in basal view were measured at preoperative (T1: within 6 months), short follow-up (T2: 2-10 weeks), and long follow-up (T3: 9-14 months). RESULTS: A significant change in alar width, alar base width, nostril width, and nostril height at the cleft side, nasal dorsum length, nasion depth, nasal tip projection, and nasal tip height was observed from T1 to T3 follow-up after rhinoplasty (P < .05), whereas the nostril height at the noncleft side was also significantly increased at T2 follow-up but the mean change in height relapsed at T3 follow-up. Alar width, alar base width, and nostril width at the noncleft side, and nasal tip angle did not change significantly after surgery at any follow-up period. CONCLUSIONS: 3D imaging evaluation after secondary cleft rhinoplasty demonstrated improved functional and aesthetic outcomes using a septal or conchal graft.

"Topographic Shift": a new digital approach to evaluating topographic changes of the female breast.

PURPOSE: To assess precise topographic changes of the breast, objective documentation and evaluation of pre- and postoperative results are crucial. New technologies for mapping the body using digital, three-dimensional surface measurements have offered novel ways to numerically assess the female breast. Due to the lack of clear demarcation points of the breast contour, the selection of landmarks on the breast is highly dependent on the examiner, and, therefore, is prone to error when conducting before-after comparisons of the same breast. This study describes an alternative to volumetric measurements, focusing on topographic changes of the female breast, based on three-dimensional scans. METHOD: The study was designed as an interventional prospective study of 10 female volunteers who had planned on having aesthetic breast augmentation with anatomical, textured implants. Three dimensional scans of the breasts were performed intraoperatively, first without and then with breast implants. The topographic change was determined as the mean distance between two three-dimensional layers before and after augmentation. This mean distance is defined as the Topographic Shift. RESULTS: The mean implant volume was 283 cc (SD = 68.6 cc, range = 210-395 cc). The mean Topographic Shift was 7.4 mm (SD = 1.9 mm, range = 4.8-10.7 mm). The mean Topographic Shifts per quadrant were: I: 8.0 mm (SD = 3.3 mm); II: 9.2 mm (SD = 3.1 mm); III: 6.9 mm (SD = 3.5 mm); IV: 1.9 mm (SD = 4.3 mm). CONCLUSION: The Topographic Shift, describing the mean distance between two three-dimensional layers (for example before and after a volume changing therapy), is a new approach that can be used for assessing topographic changes of a body area. It was found that anatomical, textured breast implants cause a topographic change, particularly on the upper breast, in quadrant II, the décolleté.

The Study of Using 3D Scan Technique to Evaluate the Expanding Method of Ear Reconstruction Before Operation.

PURPOSE: Three-dimensional scanning technology was used to measure the expansion of the area and size of auricular skin to meet the normal standard of the external ear before ear reconstruction among microtia patients. MATERIALS AND METHODS: The skin surface area of microtia patients was measured by three-dimensional scanner: the surface area (S), vertical length (A), vertical curve length (B), transverse length (C), transverse curve length data (D), and then taking the average. Corresponding measurements in healthy adults were also obtained: surface area (S0), the vertical curve length (B0), and transverse curve length (D0) of the normal external ear were obtained by scanning normal adult male ears with reference to the range of the vertical length and the transverse straight length. Mean surface area (S and S0), vertical curve length (B and B0), and transverse curve length (D and D0) were compared between microtia patients and healthy adults. RESULTS: The surface area, vertical curve length, and transverse curve length were statistically significantly higher among healthy adults. CONCLUSIONS: With the amount of expanded water injection of 120-130 ml, the expanded skin still does not reach the standard of the normal external ear in terms of skin surface area and size. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Analysis of 3D Scan Measurement Distribution with Application to a Multi-Beam Lidar on a Rotating Platform.

Multi-beam lidar (MBL) rangefinders are becoming increasingly compact, light, and accessible 3D sensors, but they offer limited vertical resolution and field of view. The addition of a degree-of-freedom to build a rotating multi-beam lidar (RMBL) has the potential to become a common solution for affordable rapid full-3D high resolution scans. However, the overlapping of multiple-beams caused by rotation yields scanning patterns that are more complex than in rotating single beam lidar (RSBL). In this paper, we propose a simulation-based methodology to analyze 3D scanning patterns which is applied to investigate the scan measurement distribution produced by the RMBL configuration. With this purpose, novel contributions include: (i) the adaption of a recent spherical reformulation of Ripley's K function to assess 3D sensor data distribution on a hollow sphere simulation; (ii) a comparison, both qualitative and quantitative, between scan patterns produced by an ideal RMBL based on a Velodyne VLP-16 (Puck) and those of other 3D scan alternatives (i.e., rotating 2D lidar and MBL); and (iii) a new RMBL implementation consisting of a portable tilting platform for VLP-16 scanners, which is presented as a case study for measurement distribution analysis as well as for the discussion of actual scans from representative environments. Results indicate that despite the particular sampling patterns given by a RMBL, its homogeneity even improves that of an equivalent RSBL.

Prospective 3D analysis of facial soft tissue augmentation with calcium hydroxylapatite.

BACKGROUND: Facial rejuvenation is an expanding field with an increasing number of treatment modalities. Several non-autologous filler materials are available for soft tissue augmentation. Calcium hydroxylapatite (CaOH) is aimed at increasing collagen neosynthesis and thereby producing long-term augmentation effects. Despite a multitude of observational reports, the field is suffering from lack of quantitative morphometric evaluation methods. OBJECTIVE: The objective of this proof-of-principle study was to investigate whether the effects of facial tissue augmentation with CaOH (RADIESSE™) can be quantified and followed up using 3D surface scanning. METHODS: 3 female subjects received augmentation of the mid and lower face with CaOH. The faces were recorded prior, directly after, and two weeks and six months after the injection using standardized photos and 3D scanning. Computational analysis allowed quantifying the change in volume and displacement of the facial surface. Additionally, a patient satisfaction questionnaire was administered. RESULTS: In all subjects, increase in facial volume could be quantified and was present after two weeks and six months. CONCLUSIONS: 3D surface scanning is an adequate tool for objective quantification of changes after facial augmentation with filler materials. Persistent volume augmentation after CaOH injections could be quantified after two weeks and six months. Evidence level: IV.

Estimation of Human Body Volume (BV) from Anthropometric Measurements Based on Three-Dimensional (3D) Scan Technique.

BACKGROUND: This study aimed to develop estimation formulae for the total human body volume (BV) of adult males using anthropometric measurements based on a three-dimensional (3D) scanning technique. Noninvasive and reliable methods to predict the total BV from anthropometric measurements based on a 3D scan technique were addressed in detail. METHODS: A regression analysis of BV based on four key measurements was conducted for approximately 160 adult male subjects. Eight total models of human BV show that the predicted results fitted by the regression models were highly correlated with the actual BV (p < 0.001). RESULTS: Two metrics, the mean value of the absolute difference between the actual and predicted BV (V error) and the mean value of the ratio between V error and actual BV (RV error), were calculated. The linear model based on human weight was recommended as the most optimal due to its simplicity and high efficiency. CONCLUSIONS: The proposed estimation formulae are valuable for estimating total body volume in circumstances in which traditional underwater weighing or air displacement plethysmography is not applicable or accessible. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Estimating the Dead Space Volume Between a Headform and N95 Filtering Facepiece Respirator Using Microsoft Kinect.

N95 filtering facepiece respirator (FFR) dead space is an important factor for respirator design. The dead space refers to the cavity between the internal surface of the FFR and the wearer's facial surface. This article presents a novel method to estimate the dead space volume of FFRs and experimental validation. In this study, six FFRs and five headforms (small, medium, large, long/narrow, and short/wide) are used for various FFR and headform combinations. Microsoft Kinect Sensors (Microsoft Corporation, Redmond, WA) are used to scan the headforms without respirators and then scan the headforms with the FFRs donned. The FFR dead space is formed through geometric modeling software, and finally the volume is obtained through LS-DYNA (Livermore Software Technology Corporation, Livermore, CA). In the experimental validation, water is used to measure the dead space. The simulation and experimental dead space volumes are 107.5-167.5 mL and 98.4-165.7 mL, respectively. Linear regression analysis is conducted to correlate the results from Kinect and water, and R(2) = 0.85.

EEG electrodes and where to find them: automated localization from 3D scans.

OBJECTIVE: The accurate localization of electroencephalography (EEG) electrode positions is crucial for accurate source localization. Recent advancements have proposed alternatives to labor-intensive, manual methods for spatial localization of the electrodes, employing technologies such as 3D scanning and laser scanning. These novel approaches often integrate Magnetic Resonance Imaging (MRI) as part of the pipeline in localizing the electrodes. The limited global availability of MRI data restricts its use as a standard modality in several clinical scenarios. This limitation restricts the use of these advanced methods. Approach: In this paper, we present a novel, versatile approach that utilizes 3D scans to localize EEG electrode positions with high accuracy. Importantly, while our method can be integrated with MRI data if available, it is specifically designed to be highly effective even in the absence of MRI, thus expanding the potential for advanced EEG analysis in various resource-limited settings. Our solution implements a two- tiered approach involving landmark/fiducials localization and electrode localization, creating an end-to-end framework. Main results: The efficacy and robustness of our approach have been validated on an extensive dataset containing over 400 3D scans from 278 subjects. The framework identifies pre-auricular points and achieves correct electrode positioning accuracy in the range of 85.7% to 91.0%. Additionally, our framework includes a validation tool that permits manual adjustments and visual validation if required. Significance: This study represents, to the best of the authors' knowledge, the first validation of such a method on a substantial dataset, thus ensuring the robustness and generalizability of our innovative approach. Our findings focus on developing a solution that facilitates source localization, contributing to the critical discussion on balancing cost effectiveness with methodological accuracy to promote wider adoption in both research and clinical settings.

Variations in volume; Breast size in trans women in relation to timing of testosterone suppression.

CONTEXT: Breast development is an important outcome for trans women receiving gender affirming hormone therapy (GAHT). Limited breast development has been reported, possibly because of testosterone exposure during puberty. The impact of puberty suppression (PS) on breast development is unclear. OBJECTIVE: To investigate the impact of PS and timing of PS prior to GAHT on breast volume and satisfaction. DESIGN: Cross-sectional study. SETTING: Tertiary gender identity clinic. PARTICIPANTS: 60 trans women (aged 17-57 years) after 4.5±1.7 years of GAHT were included of whom 23 initiated PS early in puberty (Tanner stage G2-3), 17 late in puberty (Tanner stage G4-5), and 20 started GAHT in adulthood without prior PS. MAIN OUTCOME MEASURES: Breast volume measured with a 3D scanner and breast satisfaction measured with a questionnaire. Comparisons of breast volumes were adjusted for fat percentage. RESULTS: Median breast volume was 115ml (IQR 68; 203), i.e. bra cup-size

Measuring the esthetic outcome using a three-dimensional facial scanner after parotidectomy and application of vascularized fat flaps.

BACKGROUND: Parotidectomy can affect facial symmetry. Our study evaluated the symmetry of different facial areas and upper neck after total parotidectomy and filling the area with vascularized fat flap (VFF). METHODS: Facial symmetry was evaluated in eight patients and a control group matched in terms of gender and age, using a three-dimensional (3D) facial scanner. The operated side was compared with the non-operated side and the symmetry compared with that of the control group. Scanning was performed either within the first year (group 1; n = 5) or after 3 years (group 2; n = 3) postoperatively. RESULTS: The patients' cheek and neck areas were found to be significantly more asymmetric, but the cheek area in group 2 was significantly more symmetrical when compared with group 1. CONCLUSION: VFF appeared to achieve similar facial symmetry to the matched non-operated group. Time had a positive impact on the facial symmetry. The neck area was the most asymmetric, and proved to be unreliable, regardless of whether any procedure was performed or not.

Lesion segmentation using 3D scan and deep learning for the evaluation of facial portwine stain birthmarks.

BACKGROUND: Portwine stain (PWS) birthmarks are congenital vascular malformations. The quantification of PWS area is an important step in lesion classification and treatment evaluation. AIMS: The aim of this study was to evaluate the combination of 3D scan with deep learning for automated PWS area quantization. MATERIALS AND METHODS: PWS color was measured using a portable spectrophotometer. PWS patches (29.26-45.82 cm2) of different color and shape were generated for 2D and 3D PWS model. 3D images were acquired by a handheld 3D scanner to create texture maps. For semantic segmentation, an improved DeepLabV3+ network was developed for PWS lesion extraction from texture mapping of 3D images. In order to achieve accurate extraction of lesion regions, the convolutional block attention module (CBAM) and DENSE were introduced and the network was trained under Ranger optimizer. The performance of different backbone networks for PWS lesion extraction were also compared. RESULTS: IDeepLabV3+ (Xception) showed the best results in PWS lesion extraction and area quantification. Its mean Intersection over Union (MIou) was 0.9797, Mean Pixel Accuracy (MPA) 0.9908, Accuracy 0.9989, Recall 0.9886 and F1-score 0.9897, respectively. In PWS area quantization, the mean value of the area error rate of this scheme was 2.61 ± 2.33. CONCLUSIONS: The new 3D method developed in this study was able to achieve accurate quantification of PWS lesion area and has potentials for clinical applications.

Effects of 10 KM run on foot morphology and bilateral symmetry in male recreational runners.

Foot morphology and arch integrity do not remain constant during a running bout. Previous studies have reported inconsistent changes in foot sizes and arch parameters and this discrepancy may be related to the variation in their test duration, e.g., 15-min treadmill run vs. 30 KM trial. Hence, this study sought to evaluate the change in foot morphology, arch integrity and bilateral symmetry after a 10 KM run among 19 male recreational runners. Before and after the run, a portable foot scanner was used to capture the 3-dimensional foot images and measure foot dimensions in both weight-bearing and non-weight-bearing conditions. Foot arch integrity was quantified by arch height ratio, arch height index, and arch stiffness index (ASI). Bilateral symmetry was evaluated by calculating the symmetry index. Increased foot length (p = 0.007; η p 2 = 0.18) and decreased ball girth (p = 0.038; η p 2 = 0.11) were demonstrated following the run with absolute differences of less than 2 mm. Navicular height, dorsum height, arch height ratio and arch height index significantly decreased after the run (p < 0.001; η p 2 ≥0.30) whereas ASI increased (p < 0.001, η p 2 = 0.33) and navicular height drop reduced (p < 0.001, η p 2 = 0.37). Significances of symmetry index were only demonstrated for navicular height (p = 0.019, effect size = 0.37) and arch height ratio (p = 0.019, effect size = 0.42). A few changes in foot morphology were detected but a reduction in foot arch height was demonstrated, which may give shoe manufacturers insights into shoe design. Male recreational runners were recommended to choose shoes with arch support for maintaining foot arch function during a 10 KM run.

Demonstration of Cosmetic Improvement After Cranioplasty Using a Personalized 3D-Printed Mold for Creating Polymethylmethacrylate Implants With a Simplified Process.

BACKGROUND: Although personalized polymethylmethacrylate (PMMA) implant production molds for cranioplasty are costly and time-consuming, they allow for better-quality implants. The researchers quantitatively tested the contribution of simplified, low-cost techniques to cosmetic improvement. METHODS: PMMA prosthesis was placed in a 25-year-old male patient due to osteolysis in the bone flap removed after decompression surgery. A single-sided mold was three-dimensional (3D) printed before the surgery, and the prosthesis was produced during the surgery. In addition, the change in cranial asymmetry was evaluated using a 3D surface scanner after surgery. RESULTS: The mold took half an hour to design and 5 hours to print. The mold cost about 2 dollars. The root means square (RMS) value measured to determine cranial asymmetry decreased from 5.4 mm to 2.8 mm postoperatively. The patient stated that he was pretty satisfied with the cosmetic result. CONCLUSIONS: Simple design techniques developed can offer low-cost, fast-design alternative solutions with satisfactory cosmetic results for low-income countries and patients.

Prediction of presence and severity of metabolic syndrome using regional body volumes measured by a multisensor white-light 3D scanner and validation using a mobile technology.

Aims: To test whether an index based on the combination of demographics and body volumes obtained with a multisensor 3D body volume (3D-BV) scanner and biplane imaging using a mobile application (myBVI®) will reliably predict the severity and presence of metabolic syndrome (MS). Methods and results: We enrolled 1280 consecutive subjects who completed study protocol measurements, including 3D-BV and myBVI®. Body volumes and demographics were screened using the least absolute shrinkage and selection operator to select features associated with an MS severity score and prevalence. We randomly selected 80% of the subjects to train the models, and performance was assessed in 20% of the remaining observations and externally validated on 133 volunteers who prospectively underwent myBVI® measurements. The mean ± SD age was 43.7 ± 12.2 years, 63.7% were women, body mass index (BMI) was 28.2 ± 6.2 kg/m2, and 30.2% had MS and an MS severity z-score of -0.2 ± 0.9. Features ß coefficients equal to zero were removed from the model, and 14 were included in the final model and used to calculate the body volume index (BVI), demonstrating an area under the receiving operating curve (AUC) of 0.83 in the validation set. The myBVI® cohort had a mean age of 33 ± 10.3 years, 61% of whom were women, 10.5% MS, an average MS severity z-score of -0.8, and an AUC of 0.88. Conclusion: The described BVI model was associated with an increased severity and prevalence of MS compared with BMI and waist-to-hip ratio. Validation of the BVI had excellent performance when using myBVI®. This model could serve as a powerful screening tool for identifying MS.