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The development of transcatheter mitral valve replacement therapies requires accurate post-processing analysis tools to provide D-shaped mitral annulus dimensions from 3-dimensional (3D) data. The agreement between two semi-automated, software packages to process 3D transesophageal echocardiography (TEE) data for the measurement of the mitral valve annulus dimensions was evaluated. 3DTEE data of patients with moderate–severe mitral regurgitation (MR) were postprocessed with semi-automated, vendor-independent (VI) software and vendor-specific (VS) software. Both post-processing software provided key measurements for the selection of transcatheter valve prosthesis size: annulus area, annulus circumference and the septal-to-lateral distance of the annulus. The intertrigonal distance was provided only by the VS software. The inter- and intra-observer agreements were assessed with Bland–Altman analysis. Of 105 patients (63.8 ± 11 years, 66% male) with MR, 28 had secondary MR, 45 fibroelastic deficiency, and 32 Barlow’s disease. Using VS software, the dimensions for the overall population were 16.1 ± 4.6 cm2 for annulus area, for circumference 14.4 ± 1.9 cm, intertrigonal distance 3.4 ± 0.5 cm and septal-to-lateral distance 3.8 ± 0.6 cm. Similar dimensions were obtained using VI software: 15.7 ± 4.6 cm2 for annulus area, 14.5 ± 2.0 cm for circumference, and 4.1 ± 0.6 cm for septal-to-lateral distance. The inter- and intra-observer agreement for both software programs was excellent. In conclusion, current post-processing software programs for 3DTEE data of the mitral valve annulus provide good reproducibility of key measurements to select the transcatheter prosthesis size.

Abstract Hoof conformation has been linked to catastrophic musculoskeletal injuries. Previous studies have been focused on two-dimensional measurements, thus existing knowledge on three-dimensional hoof analysis is very limited. The objective of this study was to examine the morphogeometric properties of the equine hoof using magnetic resonance imaging technology and provide a benchmark for volumetric internal and external anatomy of the hoof and to investigate the correlation between those measurements. Eighteen horses (5.8 ± 2.6 years) with no known hoof pathologies had undergone magnetic resonance imaging; transverse and mid-sagittal (T1-weighted) images were analyzed. Calibrated digital conformational pictures were also taken. In total, 14 internal and 18 external anatomy measurements were performed using Image J software. Patterns of pairwise correlations were found, that is, the distal phalanx volume was correlated with its width (r = 0.739), but not its length. Digital cushion volume was correlated with its length (r = 0.802). Navicular bone width was correlated with distal phalanx width (r = 0.710), but not deep digital flexor tendon width (r = 0.541). The distal phalanx volume and total hoof volume were correlated with the weight of the horse. Our results provide valuable linear and volumetric data for three-dimensional hoof anatomy and provide valuable information for clinicians and researchers to better identify internal hoof anatomy and differentiate pathological cases. Highlights • Volumetric measurement of healthy equine hoof. • Conformational measurements of the healthy hoof. • Hoof of Standardbred horses without clinical lameness or abnormalities. • Benchmark to characterize morphometric range of a healthy hoof. [ABSTRACT FROM AUTHOR]

Objective Stereoscopic viewing of computed tomographic angiography (CT-A) or magnetic resonance angiograms might increase the diagnostic potential of these imaging techniques. Our aim was to evaluate the benefits of a novel stereoscopic viewing system for aneurysm detection compared with standard monoscopic viewing. Methods Retrospective patient data were used for 2 different evaluations. First, monoscopic and stereoscopic CT-A viewing was compared by 14 clinicians in 10 patients with challenging (i.e., small and initially CT-A negative) aneurysms. Second, stereoscopic CT-As and the reference standard, digital subtraction angiography (DSA), were compared in 15 patients with randomly selected aneurysms by 12 clinicians. The study participants rated the presence and location of any aneurysm and its morphological characteristics. The detection rates and interrater reliability were calculated. Results The first evaluation showed superior aneurysm detection in challenging cases using stereoscopic versus monoscopic CT-A viewing (median: monoscopic, 20%; interquartile range [IQR], 10%–32.5%; stereoscopic, 40%; IQR, 27.5%–42.5%). The interrater reliability analysis revealed good to excellent agreement among raters for aneurysm detection in both viewing modalities (monoscopic, intraclass correlation coefficient [ICC(2,1)], 0.798; 95% confidence interval [CI], 0.549–0.941; stereoscopic viewing, ICC(2,1), 0.895; 95% CI, 0.770–0.968). The second part demonstrated that stereoscopic CT-A viewing is comparable to DSA viewing for aneurysm detection (median: DSA, 80%; IQR, 73%–100%; stereoscopic CT-A, 87%; IQR, 87%–93%). The interrater reliability analysis revealed excellent absolute agreement in aneurysm detection between DSA and stereoscopic CT-A viewing (DSA: ICC(2,1), 0.971; 95% CI, 0.944–0.989; stereoscopic CT-A: ICC(2,1), 0.972; 95% CI, 0.945–0.989). The aneurysm detection rates correlated significantly with the participants' years of experience. Conclusions Stereoscopic viewing of CT-As increases the diagnostic accuracy and represents a promising technique to reduce the need for invasive DSA. Highlights • Stereoscopic viewing of CT-A provides better detection of small aneurysms. • Stereoscopic viewing improves the diagnostic accuracy of CT-A. • Aneurysm detection performance correlated with the rater's years of experience. [ABSTRACT FROM AUTHOR]

Purpose: To assess interobserver variation and efficiency of various measurements on 3-dimensional transvaginal ultrasound (3DTVS) and saline infusion sonography (3D-SIS) for preoperative measurement of deep myometrial invasion (DMI) in endometrial cancer. Materials and Methods: One hundred ten women with atypical endometrial hyperplasia or endometrial adenocarcinoma had preoperative 3D-TVS and 3D-SIS. Endometrial thickness (ET), ET in percent of uterine diameter (PAP) and various volumes were measured. AUC, sensitivity, and specificity of most optimal cut-points, and kappa statistics for observer variation were calculated. Results: PAP identified two-thirds of women with DMI. ET and 3D volume measurements had substantial observer agreement compared to moderate agreement of subjective evaluation of DMI. AUC for measurements ranged 0.63-0.73 for identification of DMI. Subjective evaluation of DMI had highest AUC only marginally improved by adding PAP. Conclusion: Preoperative staging of endometrial cancer is not improved by adding 3D volume measurements to subjective evaluation, but PAP could be used to select women with a high risk of DMI for further MRI. [ABSTRACT FROM AUTHOR]

Purpose: Pseudoprogression is often indistinguishable from true tumor progression on conventional 2-dimensional (2D) MRI in glioblastoma multiforme (GBM) patients. The aim of this study was to determine the association between post-gadolinium 3-dimensional (3D) characteristics and clinical state in GBM patients.Methods: Standardized 3D brain MRI studies were performed, and contrast enhancing portions of each tumor were segmented and analyzed, blinded to clinical state, using principal component analysis (PCA), medial axis transformation (MAT), and coverage analysis. Associations between the 3D characteristics of the post-gadolinium enhanced regions and the clinical status of patients were performed.Results: A total of 15 GBM patients [male: 11 (73%); median age (range): 62 years (36-72)] with a median disease duration of 6 months (range 2-24 months) were studied cross-sectionally with 6 (40%) patients identified with tumor progression. Post-gadolinium features corresponding to the group with progressive disease exhibited a more spherical and symmetric shape relative to their stable counterparts (p = 0.005). The predictive value of a more uniformly full post-gadolinium enhanced shell to clinical progression was determined with a sensitivity of 66.7% (95% CI 29.9-92.5), specificity of 100% (54.1-100), and PPV of 100% (p = 0.028, 2-tailed Fisher’s exact test). There did not appear to be an association between the thickness of the contrast enhanced shell to clinical state.Conclusions: The application of 3D technology with post-gadolinium imaging data may inform healthcare providers with new insights into disease states based on spatial, surface, and structural patterns. [ABSTRACT FROM AUTHOR]

One of the most common procedures performed in the foot and ankle is correction of hallux abducto valgus deformity or “bunion surgery.” Most foot and ankle surgeons recognize the challenges associated with defining each patient's individual deformity and selecting the optimal procedure for the best long-term results. Using current 2-dimensional algorithms that focus on the severity of the transverse plane deformity, surgical outcomes have varied. In the past 10 years, high recurrence and complication rates for popular procedures have been reported. In the same period, the reported data have elucidated an evolving anatomic understanding of the bunion deformity, with an expansion to 3 dimensions, including the frontal/coronal plane. We present a new classification and approach for the evaluation and procedure selection for bunion surgery. We hope this conceptual treatise on hallux abducto valgus based on clinical consensus and current data will stimulate academic discussion and further research. This anatomic classification is based on the 3-dimensional anatomy of the first ray. [ABSTRACT FROM AUTHOR]

Objectives: To prospectively evaluate the diagnostic performance of 3‐dimensional (3D) shear wave elastography (SWE) for assessing thyroid nodules. Methods: A total of 176 surgically or cytologically confirmed thyroid nodules (63 malignant and 113 benign) in 176 patients who had undergone conventional ultrasound (US), 2‐dimensional (2D) SWE, and 3D SWE examinations were included in this study. Quantitative elasticity values (mean elasticity, maximum elasticity, and standard deviation of elasticity of a large region of interest and mean elasticity of a 2‐mm region of interest) were measured on 2D and 3D SWE. Diagnostic performances of conventional US, 2D SWE, and 3D SWE were assessed. The role of 2D and 3D SWE in reducing unnecessary fine‐needle aspiration (FNA) for nodules with low suspicion was also evaluated. Results: The diagnostic performances in terms of the area under the receiver operating characteristic curve were 0.612 for conventional US, 0.836 for 2D SWE (P < .001 in comparison with conventional US), and 0.839 for 3D SWE (P < .001 in comparison with conventional US). The mean elasticity achieved the highest diagnostic performance in 2D SWE, whereas the standard deviation of elasticity achieved the highest performance in 3D SWE, although no significant difference was found between them (P > .05). Three‐dimensional SWE increased the specificity in comparison with 2D SWE (88.5% versus 82.3%; P = .039). For the 37 nodules with low suspicion on conventional US imaging, 2D SWE was able to avoid unnecessary FNA in 77.1% (27 of 35) of benign nodules, and 3D SWE further increased the number to 88.6% (31 of 35). Conclusions: Three‐dimensional SWE is a useful tool for predicting thyroid nodule malignancy and reducing unnecessary FNA procedures in thyroid nodules with low suspicion of malignancy. [ABSTRACT FROM AUTHOR]

Background. Validation of three-dimensional (3D) reconstructions of full dental arches with crowns and roots based on cone beam computed tomography (CBCT) imaging represents a key issue in 3D digital dentistry. Objectives. The aim of the study was to search for the most accurate in vivo windowing-based manual tooth segmentation using CBCT. The null hypothesis was that all applied windowing protocols were equivalent in terms of in vivo tooth volume measurement using CBCT. Material and methods. This retrospective study was based on preoperative CBCT images from patients who underwent further tooth extractions for reasons independent of this study. Written informed consent was obtained from all the participants, and the study was approved by the Ethics Committee of Cliniques Universitaires Saint Luc (Brussels, Belgium). The radiological protocol was I-CAT CBCT, 0.3 mm slice thickness, 8 cm × 16 cm field of view, 120 kVp, and 18 mAs. A total of 36 teeth were extracted from 14 patients between the ages of 18 and 68 years. Using 3D Slicer software, segmentations were performed twice by 2 independent observers, with a 1-month time period between the 2 segmentations to study intra- and inter-observer repeatability and reproducibility. Four windowing protocols (level/window) were applied: 1. 1131/1858, 2. 2224/4095, 3. 1131/4095, and 4. AUTO, an automatic protocol provided by default by the software. A total of 576 segmentations were performed. Tooth volumes were automatically calculated using the software. To compare the volumes obtained from CBCT segmentations with a gold-standard method, we laser-scanned the extracted teeth. Results. Excellent intra- and inter-observer intraclass correlations were found for all of the protocols used. The best windowing protocol was 1131/1858 for both observers. Tooth volumes were obtained by manual segmentation of the CBCT images and using windowing protocol 1131/1858. No significantly different tooth volumes were found by laser scanning. Conclusions. Our null hypothesis was rejected. Only windowing protocol 1131/1858 allowed for significantly closer 3D in vivo segmentation of a tooth compared to I-CAT CBCT, with excellent intra-observer repeatability and inter-observer reproducibility. [ABSTRACT FROM AUTHOR]

This paper presents a mathematical formulation for solving a 3-dimensional and multifloor plant layout problem with safety considerations. The presented model is formulated as a mixed integer non-linear programming (MINLP) model and quantifies risk by utilizing Dow’s fire and explosion index (Dow’s F&EI) system. The applicability of the model is demonstrated by an illustrative example regarding layout optimization for the C3MR liquefaction processes. [ABSTRACT FROM AUTHOR]

Purpose: To develop a 3‐dimensional free‐breathing cardiovascular MR technique for quantifying the variation in left ventricular end‐diastolic volume (LVEDV) during the respiratory cycle. Methods: A 3‐dimensional radial trajectory with double golden‐angle ordering was used for free‐running data acquisition during free breathing in healthy volunteers (N = 8). A respiratory self‐gating signal was extracted from the center of k‐space, and data were retrospectively binned into eight respiratory phases in end‐diastole. Three‐dimensional image volumes with 2‐mm isotropic spatial resolution were reconstructed with conjugate‐gradient sensitivity encoding for acquisition durations of 4.5, 9, and 25 min. The LVEDV was manually segmented for each respiratory phase and acquisition duration. Results: Respiratory‐induced variation expressed as minimum LVEDV (during mid‐inspiration) relative to maximum LVEDV (during mid‐expiration) was 5.9 ± 0.3% for 4.5 min, 5.3 ± 0.4% for 9 min (P = 0.64 versus 4.5 min), and 5.0 ± 0.4% for 25 min (P = 0.25 versus 4.5 min, and P = 1.00 versus 9 min). Conclusions: The proposed technique enables high spatial‐resolution quantification of the respiratory variation in LVEDV during free breathing in under 5 min, and was found to be 5 to 6% for healthy volunteers. Magn Reson Med 79:2693–2701, 2018. © 2017 International Society for Magnetic Resonance in Medicine. [ABSTRACT FROM AUTHOR]

We present here a new approach to simulating three-dimensional (3D) vertex etching, which is applicable to quartz crystals and other crystals. In this paper, we describe the theoretical method behind this approach and give details regarding processing the vertex, processing the edges, distinguishing four types of vertexes, and determining the etching depth of each vertex point. [ABSTRACT FROM AUTHOR]

Purpose: Three-dimensional (3D) printing was invented in 1983 but has only just begun to influence medicine and surgery. Conversion of digital images into physical models demonstrates promise to revolutionize multiple domains of surgery. In the field of uro-oncology, researchers and clinicians have recognized the potential of this technology and are working towards making it an integral part of urological practice. We review current literature regarding 3D printing and other 3D technology in the field of urology.Method: A comprehensive assessment of contemporary literature was performed according to a modified PRISMA analysis for the purposes of this narrative review article. Medical databases that were searched included: Web of Science, EMBASE and Cochrane databases. Articles assessed were limited only to English-language peer-reviewed articles published between 1980 and 2017. The search terms used were “3D”, “3-dimensional”, “printing”, “printing technology”, “urology”, “surgery”. Acceptable articles were reviewed and incorporated for their merit and relevance with preference given for articles with high impact, original research and recent advances.Results: Thirty-five publications were included in final analysis and discussion.Conclusions: The area of 3D printing in Urology shows promising results, but further research is required and cost reduction must occur before clinicians fully embrace its use. As costs continue to decline and diversity of materials continues to expand, research and clinical utilization will increase. Recent advances have demonstrated the potential of this technology in the realms of education and surgical optimization. The generation of personalized organs using 3D printing scaffolding remains the ‘holy grail’ of this technology. [ABSTRACT FROM AUTHOR]

Introduction: Acromegaly is a rare, chronic, disfiguring, and debilitating disease caused, in 90% of cases, by a benign monoclonal growth hormone-secreting pituitary adenoma. The present study aimed to assess left ventricular (LV) rotational and twist mechanics in acromegalic patients and to compare their results to age- and gender-matched healthy controls.Methods: The present study comprised 24 acromegalic patients, from which 4 were excluded due to insufficient image quality (mean age: 57.8 ± 13.7 years, 7 men). The control group consisted of 18 age- and gender-matched healthy individuals (mean age: 54.8 ± 6.9 years, 8 men).Results: In 4 out of 20 acromegalic patients, LV showed near absence of twist, as the so-called LV "rigid body rotation" (RBR). Between all acromegalic patients without LV-RBR and controls, both LV basal (-3.76 ± 1.73 vs. -6.17 ± 2.66°, P = .004) and apical rotation (6.12 ± 4.03 vs. 10.81 ± 3.65°, P = .001) and LV twist (9.88 ± 4.74 vs. 16.98 ± 3.88°, P < .001) differed significantly. Between active and nonactive acromegaly subgroups, only the time-to-peak LV twist (377 ± 78 vs. 229 ± 97 ms, P = .005) showed significant difference.Conclusions: Acromegaly is associated with impaired LV rotation and twist as assessed by 3-dimensional speckle tracking echocardiography. LV-RBR is a frequent phenomenon in acromegaly. [ABSTRACT FROM AUTHOR]

An industrial application is presented to validate a finite element analysis of 3-dimensional, nonlinear eddy-current problems with periodic excitation. The harmonic- balance method and the fixed-point technique are applied to get the steady state solution using the finite element method. The losses occurring in steel reinforcements underneath a reactor due to induced eddy-currents are computed and compared to measurements.

Two-dimensional (2D) strain analysis is constrained by geometry-dependent reference directions of deformation (i.e. radial, circumferential, and longitudinal) following the assumption of cylindrical chamber architecture. Three-dimensional (3D) principal strain analysis may overcome such limitations by referencing intrinsic (i.e. principal) directions of deformation. This study aimed to demonstrate clinical feasibility of 3D principal strain analysis from routine 2D cine MRI with validation to strain from 2D tagged cine analysis and 3D speckle tracking echocardiography. Thirty-one patients undergoing cardiac MRI were studied. 3D strain was measured from routine, multi-planar 2D cine SSFP images using custom software designed to apply 4D deformation fields to 3D cardiac models to derive principal strain. Comparisons of strain estimates versus those by 2D tagged cine, 2D non-tagged cine (feature tracking), and 3D speckle tracking echocardiography (STE) were performed. Mean age was 51 ± 14 (36% female). Mean LV ejection fraction was 66 ± 10% (range 37-80%). 3D principal strain analysis was feasible in all subjects and showed high inter- and intra-observer reproducibility (ICC range 0.83-0.97 and 0.83-0.98, respectively-p < 0.001 for all directions). Strong correlations of minimum and maximum principal strain were respectively observed versus the following: 3D STE estimates of longitudinal (r = 0.81 and r = -0.64), circumferential (r = 0.76 and r = -0.58) and radial (r = -0.80 and r = 0.63) strain (p < 0.001 for all); 2D tagged cine estimates of longitudinal (r = 0.81 and r = -0.81), circumferential (r = 0.87 and r = -0.85), and radial (r = -0.76 and r = 0.81) strain (p < 0.0001 for all); and 2D cine (feature tracking) estimates of longitudinal (r = 0.85 and -0.83), circumferential (r = 0.88 and r = -0.87), and radial strain (r = -0.79 and r = 0.84, p < 0.0001 for all). 3D principal strain analysis is feasible using routine, multi-planar 2D cine MRI and shows high reproducibility with strong correlations to 2D conventional strain analysis and 3D STE-based analysis. Given its independence from geometry-related directions of deformation this technique may offer unique benefit for the detection and prognostication of myocardial disease, and warrants expanded investigation. [ABSTRACT FROM AUTHOR]

Background and Purpose: There remains a need to further refine the ability of clinicians to differentiate multiple sclerosis (MS) from other disease etiologies. Here, we illustrate the value of 3-dimensional (3D) geometric shape and surface lesion characteristics between disease states.Methods: Standardized 3-Tesla 3D brain magnetic resonance imaging studies were performed on enrolled MS and nonspecific white matter (NSWM) patients. Focal supratentorial lesions were identified, reconstructed using maximum intensity projection, manually segmented, and 3D printed. Printed 3D models were randomly evaluated by three blinded raters for selected shape and surface characteristics. Regression models adjusting for age, disease duration, and individual patient effects were applied to assess lesion characteristics between patient groups. Patient-level and latent class analyses between groups were performed.Results: A total of 1,001 supratentorial lesions were analyzed (710 MS; 291 NSWM) from 30 patients (19 with confirmed MS [11 female; median age = 33.6 years, range: 26.9-54.5], median disease duration = 2.2 years [.4-19.4]), 11 with verified nonspecific white matter (NSWM) disease without MS (11 female; median age = 55.0 years, range: 27.9-66.2). Lesions originating from MS in comparison to NSWM patients demonstrated a higher percentage of asymmetry (75.9% vs. 43%; OR: 4.39 [2.37-8.12]; P < .001), complex surface morphologies (65.9% vs. 27.8%; OR: 2.3 [1.74-3.05]; P < .001), and were multilobular (11.0% vs. .3%, P < .001), and elongated (12.8% vs. 2.4%, P < .001) in shape. Spatially, these traits were of higher frequency within the juxtacortical, deep white matter, and periventricular regions.Conclusion: Three-dimensional lesion data may provide new biologic insights related to injury along with offering another approach for determining the origin of lesion types. [ABSTRACT FROM AUTHOR]

Purpose To develop and evaluate a free breathing respiratory self-gated isotropic resolution technique for left ventricular (LV) volume measurements. Methods A 3D radial trajectory with double golden-angle ordering was used for free-running data acquisition during free breathing in 9 healthy volunteers. A respiratory self-gating signal was extracted from the center of k -space and used with the electrocardiogram to bin all data into 3 respiratory and 25 cardiac phases. 3D image volumes were reconstructed and the LV endocardial border was segmented. LV volume measurements and reproducibility from 3D free breathing cine were compared to conventional 2D breath-held cine. Results No difference was found between 3D free breathing cine and 2D breath-held cine with regards to LV ejection fraction, stroke volume, end-systolic volume and end-diastolic volume ( P < 0.05 for all). The test-retest differences did not differ between 3D free breathing cine and 2D breath-held cine ( P < 0.05 for all). Conclusion 3D free breathing cine and conventional 2D breath-held cine showed similar values and test-retest repeatability for LV volumes in healthy volunteers. 3D free breathing cine enabled retrospective sorting and arbitrary angulation of isotropic data, and could correctly measure LV volumes during free breathing acquisition. [ABSTRACT FROM AUTHOR]

Atomically thin materials, such as graphene, are the ultimate building blocks for nanoscale devices. But although their synthesis and handling today are routine, all efforts thus far have been restricted to flat natural geometries, since the means to control their three-dimensional (3D) morphology has remained elusive. Here we show that, just as a blacksmith uses a hammer to forge a metal sheet into 3D shapes, a pulsed laser beam can forge a graphene sheet into controlled 3D shapes in the nanoscale. The forging mechanism is based on laser-induced local expansion of graphene, as confirmed by computer simulations using thin sheet elasticity theory. [ABSTRACT FROM AUTHOR]

Ultrasound (US) examination of the common carotid artery was compared with a through-plane magnetic resonance imaging (MRI) sequence to validate a recently proposed technique for 3-D US vector flow imaging. Data from the first volunteer examined were used as the training set, before volume flow and peak velocities were calculated for the remaining eight volunteers. Peak systolic velocities (PSVs) and volume flow obtained with 3-D US were, on average, 34% higher and 24% lower than those obtained with MRI, respectively. A high correlation was observed for PSV (r = 0.79), whereas a lower correlation was observed for volume flow (r = 0.43). The overall standard deviations were ±5.7% and ±5.7% for volume flow and PSV with 3-D US, compared with ±2.7% and ±3.2% for MRI. Finally, the data were re-processed with a change in the parameter settings for the echo-canceling filter to investigate its influence on overall performance. PSV was less affected by the re-processing, whereas the difference in volume flow between 3-D vector flow imaging and MRI was reduced to -9%, and with an improved overall standard deviation of ±4.7%. The results illustrate the feasibility of using 3-D US for precise and angle-independent volume flow and PSV estimation in vivo. [ABSTRACT FROM AUTHOR]

Background The goals of this study were to evaluate the reliability of a quantitative 3-dimensional computed tomography (Q3DCT) technique for measurement of the capitellar osteochondritis dissecans (OCD) surface area, to analyze OCD distribution using a mapping technique, and to investigate associations between Q3DCT lesion quantification and demographic characteristics and/or clinical examination findings. Methods We identified patients with capitellar OCD who presented to our orthopedic sports medicine practice between January 2001 and January 2016 and who had undergone a preoperative computed tomography scan (slice thickness ≤1.25 mm). A total of 17 patients with a median age of 15 years (range, 12-23 years) were included in this study. Three-dimensional polygon models were reconstructed after osseous structures were marked in 3 planes. Surface areas of the OCD lesion as well as the capitellum were measured. Observer agreement was assessed with the intraclass correlation coefficient (ICC). Heat maps were created to visualize OCD distribution. Results Measurements of the OCD surface area showed almost perfect intraobserver agreement (ICC, 0.99; confidence interval [CI], 0.98-0.99) and interobserver agreement (ICC, 0.93; CI, 0.86-0.97). Measurements of the capitellar surface area also showed almost perfect intraobserver agreement (ICC, 0.97;CI, 0.91-0.99) and interobserver agreement (ICC, 0.86; CI, 0.46-0.96). The median OCD surface area was 101 mm 2 (range, 49-217 mm 2 ). On the basis of OCD heat mapping, the posterolateral zone of the capitellum was most frequently affected. OCDs in which the lateral wall was involved were associated with larger lesion size ( P  = .041), longer duration of symptoms ( P  = .030), and worse elbow extension ( P  = .013). Conclusions The ability to quantify the capitellar OCD surface area and lesion location in a reliable manner using Q3DCT and a mapping technique should be considered when detailed knowledge of lesion size and location is desired. [ABSTRACT FROM AUTHOR]

Recent development in artificial neural networks has led to an increase in performance, but also in complexity and size. This poses a significant challenge for the exploration and analysis of the spatial structure and temporal behaviour of such networks. Several projects for the 3D visualisation of neural networks exist, but they focus largely on the exploration of the spatial structure alone, and are using standard 2D screens as output and mouse and keyboard as input devices. In this article, we present NeuVis, a framework for an intuitive and immersive 3D visualisation of spiking neural networks in virtual reality, allowing for a larger variety of input and output devices. We apply NeuVis to NeuCube, a 3-dimensional spiking neural network learning framework, significantly improving the user's abilities to explore, analyse, and also debug the network. Finally, we discuss further venues of development and alternative render methods that are currently under development and will increase the visual accuracy and realism of the visualisation, as well as further extending its analysis and exploration capabilities. [ABSTRACT FROM AUTHOR]

Super-resolution light microscopy, correlative light and electron microscopy, and volume electron microscopy are revolutionising the way in which biological samples are examined and understood. Here, we combine these approaches to deliver super-accurate correlation of fluorescent proteins to cellular structures. We show that YFP and GFP have enhanced blinking properties when embedded in acrylic resin and imaged under partial vacuum, enabling in vacuo single molecule localisation microscopy. In conventional section-based correlative microscopy experiments, the specimen must be moved between imaging systems and/or further manipulated for optimal viewing. These steps can introduce undesirable alterations in the specimen, and complicate correlation between imaging modalities. We avoided these issues by using a scanning electron microscope with integrated optical microscope to acquire both localisation and electron microscopy images, which could then be precisely correlated. Collecting data from ultrathin sections also improved the axial resolution and signal-to-noise ratio of the raw localisation microscopy data. Expanding data collection across an array of sections will allow 3-dimensional correlation over unprecedented volumes. The performance of this technique is demonstrated on vaccinia virus (with YFP) and diacylglycerol in cellular membranes (with GFP). [ABSTRACT FROM AUTHOR]

The purpose of this study was to summarize and evaluate results of three-dimensional (3D-) planned corrective osteotomies of malunited distal radius fractures. 3D-planning techniques provide the possibility to address 3D-deformity that conventional planning methods might not address. We systematically searched PubMed, EMBASE and the Cochrane library for studies that performed a 3D-planned corrective osteotomy on patients with a malunited distal radius fracture. Fifteen studies with a total of 68 patients were included in the analysis. In 96% of cases, the preoperatively present palmar tilt, radial inclination and ulnar variance showed statistically significant improvement postoperatively with restoration to within 5° or 2 mm of their normal values. Mean flexion-extension, pro-supination and grip strength showed statistically significant improvement (p\0.05). Complications were reported in 11 out of 68 patients (16%). With the current advances in 3D printing technology, 3D-planned corrective osteotomies seem a promising technique in the treatment of complex distal radius malunions. Level of evidence IV Systematic review of case series, Level IV. [ABSTRACT FROM AUTHOR]

ABSTRACT Similar to most biological tissues, the biomechanical, and functional characteristics of the Achilles tendon are closely related to its composition and microstructure. It is commonly reported that type I collagen is the predominant component of tendons and is mainly responsible for the tissue's function. Although elastin has been found in varying proportions in other connective tissues, previous studies report that tendons contain very small quantities of elastin. However, the morphology and the microstructural relationship among the elastic fibres, collagen, and cells in tendon tissue have not been well examined. We hypothesize the elastic fibres, as another fibrillar component in the extracellular matrix, have a unique role in mechanical function and microstructural arrangement in Achilles tendons. It has been shown that elastic fibres present a close connection with the tenocytes. The close relationship of the three components has been revealed as a distinct, integrated and complex microstructural network. Notably, a 'spiral' structure within fibril bundles in Achilles tendons was observed in some samples in specialized regions. This study substantiates the hierarchical system of the spatial microstructure of tendon, including the mapping of collagen, elastin and tenocytes, with 3-dimensional confocal images. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1203-1214, 2017. [ABSTRACT FROM AUTHOR]

The aim of this prospective study was to correlate the postoperative 3-dimensional facial changes in skeletal class III deformity with sagittal jaw movements in 84 patients who had been treated by one piece Le Fort I maxillary advancement only (n = 18), mandibular setback only (n = 38), or both procedures (n = 28). At the times of evaluation before and six months after operation all patients had fixed orthodontic appliances. Soft tissue changes were evaluated on optical 3-dimensional scans, while lateral cephalograms were superimposed to assess sagittal jaw movements. Three-dimensional surface facial scans were divided into 11 regions. We modelled soft tissue changes in each region by linear regression with maxillary (point A) and mandibular (point B) sagittal movements as predictors, and adjusted for sex, age, body mass index, type of operation, and interincisal angle. We found the highest values of regression coefficients (around 0.5) for the sagittal movements of the variables points A and B within the regions of the upper and lower lips. This meant that for each mm of maxillary advancement and mandibular setback, the soft tissue moved 0.5 mm. In the sides of the face the regression coefficients were between 0.1 and 0.3, as were those within regions indirectly affected by the operations. [ABSTRACT FROM AUTHOR]

Objective Three-dimensional (3D)-printing technology is being employed in a variety of medical and surgical specialties to improve patient care and advance resident physician training. As the costs of implementing 3D printing have declined, the use of this technology has expanded, especially within surgical specialties. This article explores the types of 3D printing available, highlights the benefits and drawbacks of each methodology, provides examples of how 3D printing has been applied within the field of otolaryngology-head and neck surgery, discusses future innovations, and explores the financial impact of these advances. Data Sources Articles were identified from PubMed and Ovid MEDLINE. Review Methods PubMed and Ovid Medline were queried for English articles published between 2011 and 2016, including a few articles prior to this time as relevant examples. Search terms included 3-dimensional printing, 3 D printing, otolaryngology, additive manufacturing, craniofacial, reconstruction, temporal bone, airway, sinus, cost, and anatomic models. Conclusions Three-dimensional printing has been used in recent years in otolaryngology for preoperative planning, education, prostheses, grafting, and reconstruction. Emerging technologies include the printing of tissue scaffolds for the auricle and nose, more realistic training models, and personalized implantable medical devices. Implications for Practice After the up-front costs of 3D printing are accounted for, its utilization in surgical models, patient-specific implants, and custom instruments can reduce operating room time and thus decrease costs. Educational and training models provide an opportunity to better visualize anomalies, practice surgical technique, predict problems that might arise, and improve quality by reducing mistakes. [ABSTRACT FROM AUTHOR]

A comparative study of 3-dimensional textured glass morphologies with variable haze value and chemical texturing of the glass substrates was conducted to enhance light trapping in silicon (Si) thin film solar cells (TFSCs). The light trapping characteristics of periodic honeycomb structures show enhanced transmittance and haze ratio in numerical and experimental approaches. The periodic honeycomb structure of notched textures is better than a random or periodic carved structure. It has high transmittance of ∼95%, and haze ratio of ∼52.8%, and the haze property of the angular distribution function of transmittance shows wide scattering angles in the long wavelength region because of the wide spacing and aspect ratio of the texture. The numerical and experimental approaches of the 3-D texture structures in this work will be useful in developing high-performance Si TFSCs with light trapping. [ABSTRACT FROM AUTHOR]

Ultrasound (US) allows real-time tumor assessment. We evaluated the volumetric limits of 2-D and 3-D US, compared with magnetic resonance imaging (MRI), with a prospective institutional review board-approved clinical evaluation of US-to-MRI volumetric correlation. US images of pre- and post-neoadjuvant breast cancers were obtained. Volume discrepancy was evaluated with the non-parametric Wilcoxon signed-rank test. Expected inter-observer variability <14% was evaluated as relative paired difference (RPD); clinical relevance was gauged with the volumetric standard error of the mean (SEM). For 42 patients, 133 of 170 US examinations were evaluable. For tumors ≤20 cm3, both highly correlated to MRI with RPD within inter-observer variability and Pearson's correlation up to 0.86 (0.80 before and 0.86 after neoadjuvant chemotherapy, respectively). Lesions 20-40 cm3 had US-to-MRI discrepancy within inter-observer variability for 2-D (RPD: 13%), but not 3-D (RPD: 27%) US (SEM: 1.47 cm3 for 2-D, SEM: 2.28 cm3 for 3-D), suggesting clinical utility. Tumors >40 cm3 correlated poorly. Tumor volumes ≤20 cm3 exhibited a good correlation to MRI. Studies of clinical applications are warranted. [ABSTRACT FROM AUTHOR]

Glioblastoma (GBM) is the most aggressive adult primary brain tumor with nearly universal treatment resistance and recurrence. The mainstay of therapy remains maximal safe surgical resection followed by concurrent radiation therapy and temozolomide chemotherapy. Despite intensive investigation, alternative treatment options, such as immunotherapy or targeted molecular therapy, have yielded limited success to achieve long-term remission. This difficulty is partly due to the lack of pre-clinical models that fully recapitulate the intratumoral and intertumoral heterogeneity of GBM and the complex tumor microenvironment. Recently, GBM 3D organoids originating from resected patient tumors, genetic manipulation of induced pluripotent stem cell (iPSC)-derived brain organoids and bio-printing or fusion with non-malignant tissues have emerged as novel culture systems to portray the biology of GBM. Here, we highlight several methodologies for generating GBM organoids and discuss insights gained using such organoid models compared to classic modeling approaches using cell lines and xenografts. We also outline limitations of current GBM 3D organoids, most notably the difficulty retaining the tumor microenvironment, and discuss current efforts for improvements. Finally, we propose potential applications of organoid models for a deeper mechanistic understanding of GBM and therapeutic development., Competing Interests: All authors have no conflict of interests to declare., (© The Author(s) 2023. Published by Oxford University Press.)

The normal human adult kidney contains between 300,000 and 1 million nephrons (the functional units of the kidney). Nephrons develop at the tips of the branching ureteric duct, and therefore ureteric duct branching morphogenesis is critical for normal kidney development. Current methods for analysing ureteric branching are mostly qualitative and those quantitative methods that do exist do not account for the 3- dimensional (3D) shape of the ureteric "tree". We have developed a method for measuring the total length of the ureteric tree in 3D. This method is described and preliminary data are presented. The algorithm allows for performing a semi-automatic segmentation of a set of grey level confocal images and an automatic skeletonisation of the resulting binary object. Measurements of length are automatically obtained, and numbers of branch points are manually counted. The final representation can be reconstructed by means of 3D volume rendering software, providing a fully rotating 3D perspective of the skeletonised tree, making it possible to identify and accurately measure branch lengths. Preliminary data shows the total length estimates obtained with the technique to be highly reproducible. Repeat estimates of total tree length vary by just 1-2%. We will now use this technique to further define the growth of the ureteric tree in vitro, under both normal culture conditions, and in the presence of various levels of specific molecules suspected of regulating ureteric growth. The data obtained will provide fundamental information on the development of renal architecture, as well as the regulation of nephron number.

For the steady forced convection cooling of an isothermal spherical object in an axially symmetric incompressible fluid flow at high Péclet numbers, where the heat transport occurs mainly in a thin thermal boundary layer near the surface of the object, the relation: N u ∝ P e 1 / 2 or N u ∝ P e 1 / 3 between the Nusselt number and the Péclet number is generally found. In this paper we investigate for the general case of a 3-dimensional object immersed in a 3-d incompressible fluid flow the connection between these two characteristic numbers and obtain a similar relation: N u   ∝   P e 1 / k + 2 with integer values k ≥ 0 , where k depends only on the boundary conditions of the fluid flow field at the surface of the object. [ABSTRACT FROM AUTHOR]

Background The Assessment of Pneumatization of the Paranasal Sinuses (APPS) score is a novel and validated instrument for comprehensively evaluating the pneumatization pattern of the sinuses. Previous studies on the relationship between sinus pneumatization and clinical parameters have been hindered by cumbersome volume analysis. The purpose of this study was to determine whether the APPS score correlates with total sinus volume. Methods Semiautomated 3-dimensional (3D) volume analysis of 20 consecutive sinus computed tomography (CT) scans was performed. Total paranasal sinus volume (TSV) for each scan was then calculated. Relative total paranasal sinus volume (RTSV) was calculated by dividing TSV by the volume of the right globe. An independent reviewer then scored each CT scan using the APPS instrument. The elapsed time to perform 3D analysis and APPS scoring was recorded for each CT scan. Results The APPS score was strongly correlated with TSV by Pearson's correlation coefficient ( r = 0.893). The coefficient of determination ( r2) was 0.797. The APPS score was also strongly correlated with RTSV ( r = 0.851, r2 = 0.724). The mean elapsed time of 3D volume analysis for each CT scan was significantly greater than for APPS scoring (1187 vs. 37 seconds, p < 0.001). Conclusion The APPS score correlates strongly with both TSV and RTSV. Evaluation of paranasal sinus pneumatization by APPS score is also significantly faster than a semiautomated method for 3D volumes. The APPS instrument can be used to study large populations for relationships between clinical parameters and sinus volume. [ABSTRACT FROM AUTHOR]

Modern neuroscience often relies upon artistic renderings to illustrate key aspects of anatomy. These renderings can be in 2 or even 3 dimensions. Three-dimensional renderings are especially helpful in conceptualizing highly complex aspects of neuroanatomy which otherwise are not visually apparent in 2 dimensions or even intact biological samples themselves. Here, we provide 3 dimensional renderings of the gross- and cellular-anatomy of the rodent olfactory tubercle. Based upon standing literature and detailed investigations into rat brain specimens, we created biologically inspired illustrations of the olfactory tubercle in 3 dimensions as well as its connectivity with olfactory bulb projection neurons, the piriform cortex association fiber system, and ventral pallidum medium spiny neurons. Together, we intend for these illustrations to serve as a resource to the neuroscience community in conceptualizing and discussing this highly complex and interconnected brain system with established roles in sensory processing and motivated behaviors. [ABSTRACT FROM AUTHOR]

Mit dem erfolgten Bau der Linie U4 von der Station “Jungfernstieg” zur Station “HafenCity Universität” wurde die westliche und zentrale HafenCity mit einem leistungsfähigen, öffentlichen Personennahverkehr (ÖPNV) bereits erschlossen. Die neuen in Planung befindlichen Quartiere der östlichen HafenCity erfordern ebenfalls eine leistungsfähige ÖPNV‐Erschließung. Hierfür wird die U4 von der Haltestelle “HafenCity Universität” bis zur Haltestelle “Elbbrücken” verlängert. Bei der Baumaßnahme “U4 Tunnel Baakenhafen und Trog Baakenwerder Straße” (nachstehend T+T genannt) handelt es sich um ein ca. 710 m langes Rahmentunnelbauwerk sowie ein ca. 230 m langes Rahmentrogbauwerk als WU‐Beton‐Konstruktion. Die Strecke wird auf gesamter Länge zweigleisig ausgeführt. Die Errichtung der Ingenieurbauwerke erfolgt im Schutz wasserdichter Schlitzwandbaugruben mit rückverankerten Unterwasserbetonsohlen. Insbesondere die Planung und Ausführung der Rückverankerungen im Trogbereich erfordern eine hohe Planungs‐ und Ausführungsqualität, um Kollisionen mit im Baufeld vorhandenen Bauwerken und Rückverankerungen Dritter zu vermeiden. Für solche Planungsaufgaben ist eine dreidimensionale Ankerplanung unverzichtbar und bietet viele Vorteile sowohl in der Planung als auch bei der Qualitätssicherung während der Ausführung. U4 Hamburg HafenCity – tunnel Baakenhafen and trough Baakenwerder Straße (T+T) – anchor planning 3‐D in the interactive dialogue with planners and executors With the completing of the construction of the subway line U4 from the station “Jungfernstieg” to the station “HafenCity Universität” the western and central part of the HafenCity were connected to an efficient public transport. The new quarters in the eastern part of the HafenCity that are currently planned also need an efficient public transport. For this purpose the line U4 will be extended from the station “HafenCity Universität” to the station “Elbbrücken”. The building project “U4 Tunnel Baakenhafen und Trog Baakenwerder Straße” (hereafter called T+T) involves an approximately 710 m long tunnel as well as an approximately 230 m long trough construction made of waterproof concrete. The line will be executed double tracked. The installation of the civil engineering structure will be done in the protection of a watertight excavation pit made out of diaphragm walls and an anchored underwater concrete base. In particular the planning and execution of the grouted anchors in the area of the trough require a high quality in planning and execution to avoid collisions with other existing structures and anchors. For such planning tasks a 3‐dimensional planning of the anchors is essential and offers many advantages for planning as well as quality assurance during the construction work. [ABSTRACT FROM AUTHOR]

The serpentine flow channel can be considered as one of the most common and practical channel layouts for a polymer electrolyte membrane fuel cell (PEMFC) since it ensures an effective and efficient removal of water produced in a cell with acceptable parasitic load. Water management is one of the key issues to improve the cell performance since at low operating temperatures in PEMFC, water vapor condensation starts easily and accumulates the liquid water droplet within the flow channels, thus affecting the chemical reactions and reducing the fuel cell performance. In this article, a comprehensive three dimensional numerical simulation is carried out to understand the water droplet mobility in a serpentine gas flow channel for a wide range of surface properties, inlet air velocities, droplet positions (center or off-center, bottom or top) and droplet sizes by deploying a finite volume based methodology. The liquid-gas interface is tracked following the volume-of-fluid (VOF) method. The droplet transport is found to be greatly influenced by the surface wettability properties, inlet velocities, number of droplets emerged and initial droplet positions. Super hydrophobic surface property is not always preferable for designing the gas flow channels. It depends upon the inlet velocity conditions, droplet positions, number of droplets and surface properties. [ABSTRACT FROM AUTHOR]

Sophisticated three-dimensional animation and video compositing software enables the creation of complex multimedia instructional movies. However, if the design of such presentations does not take account of cognitive load and multimedia theories, then their effectiveness as learning aids will be compromised. We investigated the use of animated images versus still images by creating two versions of a 4-min multimedia presentation on vascular neuroeffector transmission. One version comprised narration and animations, whereas the other animation comprised narration and still images. Fifty-four undergraduate students from level 3 pharmacology and physiology undergraduate degrees participated. Half of the students watched the full animation, and the other half watched the stills only. Students watched the presentation once and then answered a short essay question. Answers were coded and marked blind. The "animation" group scored 3.7 (SE: 0.4; out of 11), whereas the "stills" group scored 3.2 (SE: 0.5). The difference was not statistically significant. Further analysis of bonus marks, awarded for appropriate terminology use, detected a significant difference in one class (pharmacology) who scored 0.6 (SE: 0.2) versus 0.1 (SE: 0.1) for the animation versus stills group, respectively (P = 0.04). However, when combined with the physiology group, the significance disappeared. Feedback from students was extremely positive and identified four main themes of interest. In conclusion, while increasing student satisfaction, we do not find strong evidence in favor of animated images over still images in this particular format. We also discuss the study design and offer suggestions for further investigations of this type. [ABSTRACT FROM AUTHOR]

Objective The aim of the study was to investigate the performance of dynamic 3-dimensional contrast-enhanced ultrasound (3D-CEUS) on assessment of efficacy of local ablation therapy of hepatocellular carcinoma (HCC) with contrast-enhanced computed tomography (CT) as reference standard. Methods Eighty-nine HCC lesions from 75 patients undergoing ultrasound-guided percutaneous thermal ablation or chemical ablation were studied by both dynamic 3D-CEUS and contrast-enhanced CT 1 month after ablation. Imaging results from two imaging modalities were evaluated independently by experienced readers to determine whether the treated lesions were ablated incompletely (residual unablated tumor) or completely. Sensitivity, specificity, positive and negative predictive values, and accuracy to identify incomplete ablation were calculated for dynamic 3D-CEUS imaging with contrast-enhanced CT as reference standard. Results Contrast-enhanced CT reported that 80.9% (72/89) of all the treated lesions were completely ablated and 19.1% (17/89) were incompletely ablated. The dynamic 3D-CEUS identified 82.0% (73/89) and 18.0% (16/89) of lesions as completely and incompletely ablated, respectively. With contrast-enhanced CT as the reference standard, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of dynamic 3D-CEUS for identifying residual unablated tumor were 88.2% (15/17), 98.6% (71/72), 93.8% (15/16), 97.3% (71/73), and 96.6% (86/89), respectively. The Kappa value for identifying residual unablated tumor between contrast-enhanced CT and dynamic 3D-CEUS was 0.89. Conclusions Dynamic 3D-CEUS is highly consistent with contrast-enhanced CT in assessment of efficacy of HCC ablation and has potential to serve as an alternative to contrast-enhanced CT in the follow-up assessment after HCC ablation. [ABSTRACT FROM AUTHOR]