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Background: It was aimed to compare conventional surgery and three-dimensional (3D) model-assisted surgery used in the treatment of calcaneal fractures. Materials & Methods: A total of 37 patients with unilateral calcaneal fractures were randomly divided into two groups as a conventional surgery group (n: 19) and a 3D model-assisted surgery group (n: 18). The preoperative, postoperative and last follow up angles of the Bohler and Gissane, calcaneal width and facet height were measured. The duration of the operation, blood loss volume, fluoroscopy usage, instrumentation time for both groups were recorded. Finally, the follow-up AOFAS scores were evaluated. A questionnaire was used to determine the perceptions of the resident doctors about the 3D model. Results: The duration of the operation, blood loss volume, fluoroscopy usage, instrumentation time for 3D model-assisted surgery group were 83.3 +/- 4.6 minutes, 83.6 +/- 4.6 ml, 6.8 +/- 1.4 times and 13.0 +/- 0.8 weeks, and as for conventional group they were 130.0 +/- 5.8 minutes, 105.1 +/- 5.6 minutes, 11.7 +/- 1.5 ml, 22.2 +/- 2.4 times and 13.3 +/- 0.8 weeks, respectively (p < 0.0001). The both groups significantly restored Bohler angle, Gissane angle, calcaneal width and calcaneal facet height after operation (p < 0.0 001). The 3D model-assisted group was significantly more succesful in restoration and protection of achieved correction of calcanel facet height (p < 0.0001). The difference was determined among the groups at the final follow-up examination with respect to the amount of change according the values achieved postop. were significant in Bohler angle (p < 0.001), calcaneal facet height (p < 0.0001) and calcaneal widht (p = 0.017). There was no significant difference between AOFAS scores of the two groups at last follow-up. Resident doctors exhibited high scores of overall satisfaction with the use of a 3D printing model. Conclusions: Compared to the conventional group, the 3D model-assisted group provide successful intervention and reduce operation, instrumentation time and the fluoroscopy usage with less blood loss. Performing 3D-assisted surgery helps the quality of reduction during the surgery and stability of internal fixation to protect achieved reduction at follow-up more succesfully. (C) 2020 Elsevier Ltd. All rights reserved., European Society of Tissue Regeneration in Orthopaedics and Traumatology (ESTROT), This paper is part of a Supplement supported by the European Society of Tissue Regeneration in Orthopaedics and Traumatology (ESTROT).

In this traffic-scene-modeling study, we propose an image-captioning network which incorporates element attention into an encoder-decoder mechanism to generate more reasonable scene captions. A visual-relationship-detecting network is also developed to detect the relative positions of object pairs. Firstly, the traffic scene elements are detected and segmented according to their clustered locations. Then, the image-captioning network is applied to generate the corresponding description of each traffic scene element. The visual-relationship-detecting network is utilized to detect the position relations of all object pairs in the subregion. The static and dynamic traffic elements are appropriately selected and organized to construct a 3D model according to the captions and the position relations. The reconstructed 3D traffic scenes can be utilized for the offline test of unmanned vehicles. The evaluations and comparisons based on the TSD-max, KITTI and Microsoft's COCO datasets demonstrate the effectiveness of the proposed framework.

Background Scapula fracture fixation and implant selection are guided by the fracture pattern and classification which requires accurate understanding and interpretation of the fracture lines. Three-Dimensional (3D) Computed Tomography (CT) based fracture pattern analysis enhances a more accurate understanding of the scapula fracture patterns. The purpose of this study was to create scapula fracture maps and identify the frequent fracture patterns using 3D reconstructed CT images. Method Seventy patients treated for scapular fractures, in a single hospital, were considered for this study. Their CT images were reconstructed into three-dimensional models (3D) and the fracture fragments were virtually reduced. The reduced 3D models were first aligned on a 3D template and 2D images were captured on the Anterior View (AV), Posterior View (PV), and Lateral View (LV). Then each fracture image was aligned on a corresponding 2D template, and the fracture lines were transferred to the template. The three separate views were used to accurately capture the propagation and exit of the fractures through the scapula anatomy. These fracture lines were compiled, and heat maps were generated to identify the frequent fracture zones of the scapula. Result The observed scapula fractures propagated through multiple regions of the bone. Overall, the three most common exit zones in the scapula borders were, lateral border (69%), medial border (67%), and superior border (60%). More specifically, superior lateral border, medial base of the scapula spine, spinoglenoid notch, and mid superior border were the frequent zones of fracture in the scapula body. Simple intraarticular fractures (transverse or oblique type) were the most common (92%) fracture type in the glenoid region. Conclusion Scapula fractures reveal repeatable patterns. The zones of recurrent fracture patterns can be identified from the fracture and heat maps. The graphical plot of fracture and heat maps may assist surgical planning and implant design optimization.

Objective: Catheters and wires are used extensively in cardiac catheterization procedures. Detecting their positions in fluoroscopic X-ray images is important for several clinical applications such as motion compensation and co-registration between 2D and 3D imaging modalities. Detecting the complete length of a catheter or wire object as well as electrode positions on the catheter or wire is a challenging task. Method: In this paper, an automatic detection framework for catheters and wires is developed. It is based on path reconstruction from image tensors, which are eigen direction vectors generated from a multiscale vessel enhancement filter. A catheter or a wire object is detected as the smooth path along those eigen direction vectors. Furthermore, a real-time tracking method based on a template generated from the detection method was developed. Results: The proposed framework was tested on a total of 7,754 X-ray images. Detection errors for catheters and guidewires are 0.56 0.28 mm and 0.68 0.33 mm, respectively. The proposed framework was also tested and validated in two clinical applications. For motion compensation using catheter tracking, the 2D target registration errors (TRE) of 1.8 mm 0.9 mm was achieved. For co-registration between 2D X-ray images and 3D models from MRI images, a TRE of 2.3 0.9 mm was achieved. Conclusion: A novel and fully automatic detection framework and its clinical applications are developed. Significance: The proposed framework can be applied to improve the accuracy of image-guidance systems for cardiac catheterization procedures.

[EN] The digitalization of the historical-architectural heritage for virtual reality (VR) applications is crucial within the contemporary scientific and technical debate for several aspects. In fact, beyond the exploration for education and entertainment purposes, the employment of three-dimensional (3D) reality-based and computer-based models and environments seems to be very promising for performance assessment and risk management as well. Particularly, in order to develop and validate smart, low-cost and user-friendly tools, which might apply even in cases of limited time and budget, the present paper is going to propose a methodological workflow based on thematic virtual tours of 360° scenes, which integrate a variety of informative contents and digital products as external hotspots/switches. The VR tours, where 3D models might play a key role for an accurate representation of relevant parts and/or analytical elaboration of further data, are conceived as flexible and scalable solutions, supporting users, technicians and authorities through remote access, diagnosis of the state of conservation and communication of safety measures. The application of the proposed methods and techniques to a representative case study, the Norman-Swabian Castle of Gioia del Colle (Ba), South Italy, is presented in order to illustrate the achievable results and highlight the benefit of innovative “digital” solutions for data collection, storage and communication, compared to the traditional “analogical” practices. In detail, a Web-GIS platform, developed within a previous research project, is integrated with direct links to three thematic virtual tours that provide added contents for inclusive dissemination (timeline schemes, aerial views, 3D sculptural and architectural details), performance assessment (diagnostic reports, decay maps, 3D reconstructions of technical components) and risk management (exit signs, help instructions, warnings). Thus, the VR tours, while documenting realistically the state of the site, might act as host environments of digital products, at increasing complexity, all displayed according to an intuitive and accessible communication approach.Highlights:• Virtual tours of 360° scenes, linking thematic digital contents, are proposed as intuitive and versatile tools for smart documentation, conservation and protection of historical buildings.• The role of 3D reality-based and computer-based models is discussed toward their integration and correlation within thematic virtual tours of 360° scenes.• The potential of immersive environments for sharing knowledge about conservation issues and training users on safety measures in historic buildings is underlined., [ES] La digitalización del patrimonio histórico-arquitectónico en aplicaciones de realidad virtual (RV) es crucial dentro del actual panorama científico-técnico por varias razones. De hecho, más allá de su exploración con meros fines educativos y de entretenimiento, el empleo de modelos tridimensionales (3D) basados en la realidad y entornos computacionales se muestran igualmente como herramientas muy atractivas en la evaluación del desempeño y la gestión de riesgos. Sobre todo, con el fin de desarrollar y validar herramientas inteligentes, de bajo costo y de fácil empleo, que puedan aplicarse incluso en casos con disponibilidad temporal o presupuesto limitado. El presente trabajo propone un proceso metodológico basado en los desarrollos de recorridos virtuales temáticos de escenas en 360°, que integran una variedad de contenidos informativos y productos digitales como conexiones externas/interruptores. Los recorridos de RV, donde los modelos 3D pueden jugar un papel clave para la representación precisa y/o el análisis de los datos más a fondo, se conciben como soluciones flexibles y escalables, que apoyan a los usuarios, técnicos y autoridades a lo largo de la divulgación pública, el diagnóstico del estado de conservación y la comunicación de las medidas de seguridad que sea necesario adoptar para la conservación integral del patrimonio histórico-arquitectónico. Con el fin de ilustrar los resultados alcanzables mediante la metodología propuesta y resaltar el beneficio de la innovación de soluciones “digitales” en la captura, el almacenamiento y la presentación de datos, en comparación con las prácticas “analógicas” tradicionales, estas técnicas y métodos se aplican a un caso representativo de estudio, el castillo normando-suabo de Gioia del Colle (Ba), sito en el sur de Italia. Concretamente, una plataforma Web-GIS, que se encuentra desarrollada dentro de un proyecto de investigación anterior, integra enlaces directos a tres recorridos virtuales que brindan contenidos para la divulgación inclusiva (esquemas de línea de tiempo, vistas aéreas, detalles arquitectónicos y escultóricos en 3D), evaluación del desempeño (informes de diagnóstico, mapas de descomposición, reconstrucciones 3D de componentes técnicos) y gestión de riesgos (señales de salida, instrucciones de ayuda y advertencias). Por lo tanto, los recorridos de RV, si bien documentan de manera realista el lugar, pueden actuar como entornos de productos digitales, con una creciente complejidad, todos ellos representados de acuerdo a un enfoque de comunicación intuitivo y accesible.

The primary objective of this article is to explore effects of latest development in the area of three dimensional (3D) printing & to assess its abilities, and further undertake helpful reporting. Here the focus is to assess advantages of 3D printing in orthopedics and analyze how 3D printed models help solve complex 3D orthopedics distortions. This study identified that 3D models manufactured by 3D printing models reduce medical parts development cost and surgical planning time. Integrating 3D printing with orthopaedics helps in understanding the conditions of problems and achieving the operation successfully. This technology can enable doctors/surgeons to design, produce, recreate and plan operations more accurately, carefully, and economically. 3D models can assist specialists with a visual comprehension of the patient-particular pathology and life structures. Innovation in 3D printing initiated a scaffold for the virtual outline and execution of medical procedures. This research proposes the utilisation of 3D printers as an elective procedure for the fabrication of parts. It empowers surgeons/patients for better training, education and research. In the future, there is a foreseeable expansion of additive manufacturing in orthopedics.

Ecosystem restoration has been practiced for over a century and is increasingly supported by the emergent applied science of restoration ecology. A prerequisite for successful ecosystem restoration is determining meaningful and measurable goals. This requires tools to monitor success in a standardized way. Photogrammetry uses images to reconstruct landscapes and organisms in three dimensions, enabling non-invasive measurement of key success indicators with unprecedented accuracy. We propose photogrammetry can improve restoration success by: (i) facilitating measurable goals; (ii) innovating and standardizing indicators of success; and (iii) standardizing monitoring. While the case we present is specific to coral reefs, photogrammetry has enormous potential to improve restoration practice in a wide range of ecosystems.

Background Proper use of three-dimensional (3D) models generated from medical imaging data in clinical preoperative planning, training and consultation is based on the preliminary proved accuracy of the replication of the patient anatomy. Therefore, this study investigated the dimensional accuracy of 3D reconstructions of the knee joint generated from computed tomography scans via automatic segmentation by comparing them with 3D models generated through manual segmentation. Methods Three unpaired, fresh-frozen right legs were investigated. Three-dimensional models of the femur and the tibia of each leg were manually segmented using a commercial software and compared in terms of geometrical accuracy with the 3D models automatically segmented using proprietary software. Bony landmarks were identified and used to calculate clinically relevant distances: femoral epicondylar distance; posterior femoral epicondylar distance; femoral trochlear groove length; tibial knee center tubercle distance (TKCTD). Pearson's correlation coefficient and Bland and Altman plots were used to evaluate the level of agreement between measured distances. Results Differences between parameters measured on 3D models manually and automatically segmented were below 1 mm (range: −0.06 to 0.72 mm), except for TKCTD (between 1.00 and 1.40 mm in two specimens). In addition, there was a significant strong correlation between measurements. Conclusions The results obtained are comparable to those reported in previous studies where accuracy of bone 3D reconstruction was investigated. Automatic segmentation techniques can be used to quickly reconstruct reliable 3D models of bone anatomy and these results may contribute to enhance the spread of this technology in preoperative and operative settings, where it has shown considerable potential.

In the aviation industry, cable bracket is one of the most common parts. The traditional assembly state inspection method of cable bracket is to manually compare by viewing 3D models. The purpose of this paper is to address the problem of inefficiency of traditional inspection method. In order to solve the problem that machine learning algorithm requires large dataset and manually labeling of dataset is a laborious and time-consuming task, a simulation platform is developed to automatically generate synthetic realistic brackets images with pixel-level annotations based on 3D digital mock-up. In order to obtain accurate shapes of brackets from 2D image, a brackets recognizer based on Mask R-CNN is trained. In addition, a semi-automatic cable bracket inspection method is proposed. With this method, the inspector can easily obtain the inspection result only by taking a picture with a portable device, such as augmented reality (AR) glasses. The inspection task will be automatically executed via bracket recognition and matching. The experimental result shows that the proposed method for automatically labeling dataset is valid and the proposed cable bracket inspection method can effectively inspect cable bracket in the aircraft. Finally, a prototype system based on client-server framework has been developed for validation purpose.

This study aims to model climate change based on rainfall, air temperature, pressure, humidity and wind with grADS software and create a global warming module. This research uses 3D model, define, design, and develop. The results of the modeling of the five climate elements consist of the annual average temperature in Indonesia in 2009-2015 which is between 29oC to 30.1oC, the horizontal distribution of the annual average pressure in Indonesia in 2009-2018 is between 800 mBar to 1000 mBar, the horizontal distribution the average annual humidity in Indonesia in 2009 and 2011 ranged between 27-57, in 2012-2015, 2017 and 2018 it ranged between 30-60, during the East Monsoon, the wind circulation moved from northern Indonesia to the southern region Indonesia. During the west monsoon, the wind circulation moves from the southern part of Indonesia to the northern part of Indonesia. The global warming module for SMA/MA produced is feasible to use, this is in accordance with the value given by the validate of 69 which is in the appropriate category and the response of teachers and students through a 91% questionnaire.

BACKGROUND The quadriceps femoris may be a reliable reference to proper alignment in total knee arthroplasty (TKA). We previously showed the quadriceps vector (QV) to be the most parallel to the spherical axis (SA-center hip to center medial condyle) for healthy knees. The purpose of this study was to determine whether the QV is the most parallel to the SA in knees with varus osteoarthritis (OA). METHODS CT imaging for 35 varus OA and 40 healthy Japanese knees was used to construct 3D models of the femur, patella and each quadriceps component for each subject. The QV was calculated using principal component analysis for direction and was compared with the relationship of the QV to the measurement axes of the lower extremity, including the anatomical, mechanical and spherical axes. RESULTS The direction of the QV for the OA knee group was different from that for the healthy knee group in 3D space (medio-lateral direction: women, p = 0.532, men, p = 0.540; antero-posterior direction: women, p = 0.141, men, p

Multimedia data play an important role in many areas such as business, medicine, and entertainment. Multimedia contents are often vulnerable to malicious interventions due to the advancement in multimedia innovations. It is, therefore, highly necessary to verify the integrity and authenticity of multimedia content through appropriate security measures. This increases the need to establish a range of watermarking schemes for several security purposes, including copyrights and authentication. Digital watermarking has proven an effective and influential approach for 3D models among various other authentication strategies. In this study, an in-depth review of different types of 3D model representations, watermarking techniques in spectral and spatial domains along with most common attacks that can be applied to them are presented. The paper concludes with a set of observations along with some of the research issues and challenges which are needed to be studied further.

The study aimed at introducing a digital method of locating the osteotomy position of the zygomatic arch during surgery and analyze the accuracy of this method. Patients with a prominent zygomatic bone who underwent zygomatic arch osteotomy and reduction in the orthognathic surgery department of our hospital were selected. Preoperative and postoperative computed tomography (CT) data of the patients were imported into modeling and analysis software Mimics 23.0 in DICOM format to construct 3D models of the zygomatic bone and zygomatic arch region. The data were obtained by locating the simulated osteotomy position of the zygomatic arch before the surgery, applying the digitally modeled osteotomy position of the zygomatic arch during the surgery, and locating the actual osteotomy position of the zygomatic arch after the surgery. The accuracy of the experimental method was verified by matching the preoperative simulation data with the postoperative osteotomy data. A Wilcoxon rank sum test was performed to compare the 20 cases’ osteotomy positions obtained by preoperative simulation with the actual postoperative position. There was no significant difference in zygomatic arch osteotomy position between the preoperative simulation and the real postoperative position (Z=-1.867, P=0.062). The digital method to locate the zygomatic arch osteotomy seems to show an acceptable accuracy to achieve the proper osteotomy position and, therefore, should adopted whenever appropriate.

There is a growing demand for information and computational technology for surgeons help with surgical planning as well as prosthetics design. The two-dimensional images are registered to the three-dimensional (3D) model for high efficiency. To reconstruct the 3D model of knee joint including bone structure and main soft tissue structure, the evaluation and analysis of sports injury and rehabilitation treatment are detailed in this study. Mimics 10.0 was used to reconstruct the bone structure, ligament, and meniscus according to the pulse diffusion-weighted imaging sequence (PDWI) and stir sequences of magnetic resonance imaging (MRI). Excluding congenital malformations and diseases of the skeletal muscle system, MRI scanning was performed on bilateral knee joints. Proton weighted sequence (PDWI sequence) and stir pulse sequence were selected for MRI. The models were imported into Geomagic Studio 11 software for refinement and modification, and 3D registration of bone structure and main soft tissue structure was performed to construct a digital model of knee joint bone structure and accessory cartilage and ligament structure. The 3D knee joint model including bone, meniscus, and collateral ligament was established. Reconstruction and image registration based on mimics and Geomagic Studio can build a 3D model of knee joint with satisfactory morphology, which can meet the requirements of teaching, motion simulation, and biomechanical analysis.

Estimates of interstellar extinction are essential in a broad range of astronomical research. In the last decades, several maps and models of the large scale interstellar extinction in the Galaxy have been published. However, these maps and models have been developed in different programming languages, with different user interfaces and input/output formats, which makes using and comparing results from these maps and models difficult. To address this issue, we have developed a tool called GALExtin (\url{http://www.galextin.org}) - that estimates interstellar extinction based on both 3D models/maps and 2D maps available. The user only needs to provide a list with coordinates (and distance) and to choose a model/map. GALExtin will then provide an output list with extinction estimates. It can be implemented in any other portal or model that requires interstellar extinction estimates. Here, a general overview of GALExtin is presented, along with its capabilities, validation, performance and some results., Comment: 12 pages, 2 figures

This article discusses the implementation of digital technologies in the mining industry, as well as the economic effect of their implementation. The advantages of using 3D models, “smart ear” systems, “Blast movement technology” are substantiated. It was determined that Industry 4.0 opens up new prospects for the development of the mining industry, creating opportunities for productivity growth with improved labor safety. Thanks to the introduction of geotechnology - Mining 4.0 (Industry 4.0 in the mining industry), including such modern digital technologies as deserted robotic complexes of mining and quarry equipment, ubiquitous digital telemetry, the Internet of Things and machine-to-machine communications, digital 3D modeling and artificial intelligence in the mining industry becomes a high-tech production. The author analyzed the forms of penetration of Industry 4.0 technologies into the mining industries and the international experience of using Mining 4.0, showing the advantages of the further development of geotechnology in a new technological era and the economic effect of their use.

Purpose: The aim of this study was to determine the efficacy of using 3D printing models in the learning process of orbital anatomy and pathology by ophthalmology residents. Methods: A quasi-experimental study was performed with 24 residents of ophthalmology at Mashhad University of Medical Sciences. Each stratum was randomized into two groups. The educational booklets were distributed, and various forms of orbital 3D models were printed from orbital computed tomography (CT) scans. Knowledge enhancement on the topics was measured by comparing pretest and posttest scores. Results: Thirteen residents who were trained using traditional methods were deemed the control group; while 11 residents who were trained using the 3D printed models were classed as the intervention group. The control group was younger than the intervention group (P = 0.047). The results showed that there was a statistically significant difference in the total posttest scores between the two groups. Based on the repeated measures of the analysis of variance (ANOVA), score variables were significant between the two groups (P = 0.008). Interestingly, the use of the 3D educational model was more effective and statistically significant with the year one residents as compared to the year two residents (P = 0.002). Conclusion: This study is the first one in Iran quantifying the effects of learning using 3D printed models in medical education. In fact, 3D modeling training is seemingly effective in teaching ophthalmic residents. As residents have never encountered such technology before, their experience using 3D models proved to be satisfactory and had a surprising positive effect on the learning process through visual training.

Over the past 20 years, 3D (three-dimensional) technology has become widespread as an advanced method for creating digital models of objects. This direction of science is used not only in the technical and space fields, but in the storage and protection of pharmaceuticals, museum exhibits and other cultural values in the form of digital data. Currently, the method based on laser scanning is of particular importance for obtaining accurate images among wide-sector methods for constructing digital models of objects. Although the limited application of the method is associated with financial and economic problems, the accuracy of data, the creation of artificial objects, characters using various editors and programs, their animation, as well as harmony with real objects and interiors have become key factors in the spread of this technology. The article analyzes the process of obtaining a three-dimensional image of a model using two cameras using three-dimensional graphics editors. Keywords: 3D technology, digital model, graphic representation, Monge method, modeling.

Study design Experimental study. Objectives The goal of this study was to develop a 3D-printed pedicle subtraction osteotomy (PSO) guide plate system. A 3D model and postoperative CT data were used to evaluate the accuracy of osteotomy with this system. Summary of background data The key to the success of spinal orthopaedic treatment is an effectively performed osteotomy. A 3D-printed osteotomy plate can be used for preoperative surgical planning. Due to the anatomical complexity of the spinal region, the clinical application of 3D-printed osteotomy plates remains challenging. Methods The CT scans of 10 patients with thoracolumbar spinal deformities were obtained in the DICOM format. The diseased vertebrae and adjacent vertebrae were reconstructed and reduced by computer-aided design (CAD) software, and an osteotomy plate was designed for the diseased vertebrae. The 3D-printed spinal model and osteotomy plate were used to simulate the operation for PSO. After the operation, the vertebral body treated by osteotomy underwent a CT scan, and the findings were compared with the preoperative design to evaluate the osteotomy accuracy. Results The new 3D guide plate and spine model were used to successfully simulate 10 cases of PSO, and the comparison of the preoperative and postoperative states indicated that the osteotomy outcomes were excellent. Conclusions The new 3D-printed PSO guide plate system can be used for preoperative osteotomy planning and demonstrates good accuracy. The results can be used to develop 3D-printed plans for PSO in clinical practice.Level of Evidence: 3.

Objective The low accuracy limits the use of fibular free flap (FFF). We apply digital navigation and 3D printing model technology in mandibular reconstruction to improve FFF’s accuracy. Methods 34 patients who underwent with FFF to repair mandibular defects were divided into Navigation Group (13 cases, using digital navigation and 3D printing model) and Control Group (21 cases, only 3D printing model). We retrospectively reviewed patients’ hospitalization information and evaluated patients by subjective and objective items, such as UW-Qol scale, CT data. Results The operation time of Navigation Group was higher significantly than Control Group (10.36 ± 1.87vs9.00 ± 1.34 h).There were no significant differences in early postoperative complications. The Qol score of appearance, motion, anxiety were higher significantly in Navigation Group. The CT results showed that mandibular angle deviation and chin deflection of Navigation Group were better significantly than Control Group (1.72 ± 1.29° vs 3.69 ± 1.67°, 2.45 ± 1.39 vs 5.19 ± 2.13 mm). Conclusions The digital navigation can improve FFF’s accuracy in mandibular reconstruction. It doesn’t significantly increase complications. The digital navigation’s installation and operation methods should be simplified to shorter operation time and expand its application.

Objectives To compare the geometric accuracy and measurement reliability of 3-dimensional (3D) reconstructed models of the mandible created from cone beam computed tomography (CBCT) images obtained with 0.2-mm and 0.4-mm voxel sizes with the reference standard model and compare the accuracy of the CBCT-based models to each other. Study design The reference standard 3D model of a dry human mandible was obtained using a white light scanner. The mandible was scanned with CBCT 10 times at each voxel size. The models created from the CBCT data were compared with the reference standard by using a point-based rigid registration algorithm where the distance differences between the superimposed CBCT models and the reference standard model were recorded. The measurements derived from the 2 CBCT-based scans were also compared. Results Mean deviations from the reference standard for 0.2-mm and 0.4-mm voxel scans were 0.4342 mm and 0.4580 mm, respectively (P ≥ .16). The CBCT scans with both 0.2-mm and 0.4-mm voxels produced good measurement reliability and did not significantly differ from each other (P ≥ .20). Conclusions CBCT scans with 0.2-mm and 0.4-mm voxel sizes delivered similarly accurate models. Larger voxels can be used to minimize radiation exposure.

Background For visually impaired or blind patients, the experience of pregnancy sets them apart from nondisabled people for whom viewing of the first ultrasound has become a social and emotional milestone. Objective We proposed the use of 3D-printed models to allow the societal inclusion of visually impaired or blind expectant parents. Patient involvement Visually impaired expectant parents were proposed to touch a 3D printed sensory vector of their prenatal classic ultrasonography. Methods After a classic ultrasound assessment was performed, selected volumes were processed and 3D-printed with acrylonitrile butadiene styrene. Patient satisfaction was recorded after they manipulated the models. Results A total of 42 prenatal 3D prints were for 12 expectant parents, used during 20 ultrasonographic sessions with visually impaired or blind expectant parents. During 13 of them (65%), it was the mother who was affected by a visual loss whereas the father was the parent affected by the disability during 7 sessions (35%). The parent affected by the disability was congenitally blind and Braille-reader in 9 ultrasonography sessions (45%). All expectant visually impaired or blind parents expressed very significant satisfaction with the use of 3D models for inclusive use. Discussion We have shown that acrylonitrile butadiene styrene-printed models improve the sonographic experience of visually impaired or blind expectant parents. They can thereby perform their own mental representation process by extrapolating sensory information obtained from the 3D tactile support. Practical value These low-cost 3D-printed models improve the inclusion of visually impaired or blind expectant parents, by offering them a sensory vector of information.

Epignathus is a rare congenital orofacial teratoma that arises from the sphenoid region of the palate or the pharynx. It occurs in approximately 1:35,000 to 1:200,000 live births representing 2% to 9% of all teratomas. We present the case of a newborn of 39.4 weeks of gestation with a tumor that occupied the entire oral cavity. The patient was delivered by cesarean section. Oral resection was managed by pediatric surgery. Plastic surgery used virtual 3-dimensional models to establish the extension, and depth of the tumor. Bloc resection and reconstruction of the epignathus were performed. The mass was diagnosed as a mature teratoma associated with cleft lip and palate, nasoethmoidal meningocele that conditions hypertelorism, and a pseudomacrostoma. Tridimensional technology was applied to plan the surgical intervention. It contributed to a better understanding of the relationships between the tumor and the adjacent structures. This optimized the surgical approach and outcome.

Micro-osteoperforation (MOP), a minimally invasive technique for accelerating the rate of orthodontic tooth movement has been research extensively, but with varied clinical results.To compare the efficacy of one-time versus two-time micro-osteoperforation on the rate of maxillary canine retraction, its influence on anchorage loss, canine angulation and the levels of interleukin (IL-1β) in gingival crevicular fluid (GCF).The split-mouth study included 16 patients in which the left and right sides were randomly allocated to the control side (one-time MOP) and experimental side (two-time MOP). MOP was performed on both sides distal to the maxillary canines and canine retraction was carried out using NiTi closed coil springs (150gm) and direct anchorage with miniscrew implants. The second MOP was performed on experimental side one month after the first MOP. The rate of canine movement was assessed using 3D model superimposition over a period of six months. The type of tooth movement, anchorage loss and levels of IL-1β were also evaluated.Sixteen patients (mean age, 17.87±3.34 years) were analysed for a rate of canine retraction, anchorage loss, and type of tooth movement, while 15 patients were analysed for IL-1β. The rate was significantly higher on two-time MOP side after two months (P0.001). No statistical difference was found in anchorage loss and controlled tipping of canines was observed. The IL-1β levels immediately after 2The two-time intervention of MOP is more efficacious than one-time MOP in accelerating tooth movement.

Material artifacts play an important role in many learning environments. Such artifacts can include sketches, manipulatives, 3D models, toys and games, or the scrap materials found in makerspaces. ...

The aim of this paper is to present the use of 3D models and augmented reality (AR) to study and communicate architectural and urban values and, therefore, favor the development of dedicated forms of “smart heritage”. The study rises from a reflection on the concept of “heritage”, as defined in the international documents, intended as an evolving idea that puts together tangible and intangible aspects. Moreover, digital technologies favor “phygital” applications where the digital dimension support the traditional ones. In this way, AR allows the superimposition of multimedia information to heritage, respecting the historical matter of the artefacts, and supporting a “smart heritage” application. In particular, mobile AR, with real-time and ubiquitous visualizations, offers the opportunity to show past urban and architectural configurations to investigate and describe the transformations that have led to the current configuration, and consequently highlighting the present historical and architectural values of the buildings. Two case studies are presented: the square of St. Basilio Monastery, with its historical transformations, and the Basilica of Collemaggio, a pivotal building in the rites of “Perdonanza Celestiniana”.

Archaeological sites in urban areas are often poorly integrated with the modern urban fabric and appear as “trenches” at a lower level than the road. They become neglected and unvalued places. The study of archaeological ruins in urban centres must involve archaeologists and architects to integrate restoration, enhancement and improvement of physical and visual accessibility projects. New digital technologies can improve these activities thanks to 3D models, “digital replicas” that allow even remote study (especially during a pandemic). The paper presents the case study of a private Roman-imperial bath in Catania. The open-air site is located at a depth of 3 metres above the road level and is not exploited. Our study consisted of historical-bibliographical research, direct and SfM surveys that allowed creating a high-resolution textured 3D model. We have extracted orthophotos and sections for geometric and technical-constructive analyses and recognition of decay from this model. We drew up an archaeological restoration and valorisation design. In addition, we imported the model into the Sketchfab portal. So, we enriched the mesh with information from the analyses employing specific tags about annotations, 2D drawings, historical and technical-scientific information. In this way, the model becomes an interactive document to monitor over time the conservation state, validate the restoration design and contribute to the valorisation of the site. This is an easy tool of exchange between all involved users (researchers, professions and students). Thus, the digital replica also represents a very high potential for dissemination purposes.

Through the implementation of the free website/smartphone application Sketchfab, we have found a simple means to introduce 3D visual tools into the chemistry classroom. Sketchfab stores 3D models and animations with free cross-platform accessibility. Blender is a free 3D modeling tool that has been used to prepare models and animations for dissemination via Sketchfab. By combining these two tools, we have created and are currently maintaining an ever-growing free library of interactive 3D models on various chemistry topics. Through the Sketchfab smartphone application, these models are viewable in augmented reality on most devices. Topics include molecular motion, isomerism, molecular orbital theory, chirality, and polymerization.

Introduction:Adolescents with CHD require transition to specialised adult-centred care. Previous studies have shown that adolescents’ knowledge of their medical condition is correlated with transition readiness. Three-dimensional printed models of CHD have been used to educate medical trainees and patients, although no studies have focused on adolescents with CHD. This study investigates the feasibility of combining patient-specific, digital 3D heart models with tele-education interventions to improve the medical knowledge of adolescents with CHD.Methods:Adolescent patients with CHD, aged between 13 and 18 years old, were enrolled and scheduled for a tele-education session. Patient-specific digital 3D heart models were created using images from clinically indicated cardiac magnetic resonance studies. The tele-education session was performed using commercially available, web-conferencing software (Zoom, Zoom Video Communications Inc.) and a customised software (Cardiac Review 3D, Indicated Inc.) incorporating an interactive display of the digital 3D heart model. Medical knowledge was assessed using pre- and post-session questionnaires that were scored by independent reviewers.Results:Twenty-two adolescents completed the study. The average age of patients was 16 years old (standard deviation 1.5 years) and 56% of patients identified as female. Patients had a variety of cardiac defects, including tetralogy of Fallot, transposition of great arteries, and coarctation of aorta. Post-intervention, adolescents’ medical knowledge of their cardiac defects and cardiac surgeries improved compared to pre-intervention (p < 0.01).Conclusions:Combining patient-specific, digital 3D heart models with tele-education sessions can improve adolescents’ medical knowledge and may assist with transition to adult-centred care.

Astrocytes connect the vasculature to neurons mediating the supply of nutrients and biochemicals. They are involved in a growing number of physiological and pathophysiological processes that result from biophysical, physiological, and molecular interactions in this neuro-glia-vascular ensemble (NGV). The lack of a detailed cytoarchitecture severely restricts the understanding of how they support brain function. To address this problem, we used data from multiple sources to create a data-driven digital reconstruction of the NGV at micrometer anatomical resolution. We reconstructed 0.2 mm3 of the rat somatosensory cortex with 16 000 morphologically detailed neurons, 2500 protoplasmic astrocytes, and its microvasculature. The consistency of the reconstruction with a wide array of experimental measurements allows novel predictions of the NGV organization, allowing the anatomical reconstruction of overlapping astrocytic microdomains and the quantification of endfeet connecting each astrocyte to the vasculature, as well as the extent to which they cover the latter. Structural analysis showed that astrocytes optimize their positions to provide uniform vascular coverage for trophic support and signaling. However, this optimal organization rapidly declines as their density increases. The NGV digital reconstruction is a resource that will enable a better understanding of the anatomical principles and geometric constraints, which govern how astrocytes support brain function.

Background: A reliable assessment of the ankle using weightbearing radiography remains challenging. Semiautomated 3-dimensional (3D) measurements derived from weightbearing computed tomography (WBCT) scans may provide a more reliable approach. Methods: Thirty healthy individuals without any foot and ankle disorder were analyzed. We assessed 6 widely used ankle parameters (4 angles and 2 distances) using either semiautomated 3D (based on WBCT scans) or traditional 2-dimensional (2D; based on conventional radiographs) measurements. The reliability and discrepancy between both techniques were compared using intraclass correlation coefficients and the Bland-Altman method. Results: Five of 6 variables showed a lower reliability when derived from 2D measurements. The mean of 3 variables differed between the techniques: the 3D technique assessed that the talonavicular coverage angle was 18.9 degrees higher, the axial talocalcaneal angle was 5.5 degrees higher, and the talocalcaneal overlap was 3.7 mm lower when compared with 2D measurements. Conclusion: Semiautomated 3D measurements derived from WBCT scans provide more reliable information on ankle alignment compared with 2D measurements based on weightbearing radiographs. Future studies may show to what extent these parameters could contribute to current diagnostic algorithms and treatment concepts. Level of Evidence: Not applicable.

Face shield is one of the important PPE (Personal Protective Equipment) for health workers in health services in the era of the COVID-19 pandemic as it is today. The limited number of face shield will certainly hamper the health services provided by the hospital. This Community Services activity was carried out at RSI Sultan Agung and RSIGM Sultan Agung to provide training on making face shield independently and also maintenance, so that face shield is more durable and not easily damaged. The tool used is a 3D printer which is easy to operate. 3D Printing technology will produce solid objects, and not like printing a sheet of paper on a printer that is commonly used. Design 3D models using CAD software. This activity was attended by 80 participants. 91.25% of participants are interested in making their own face shields as an effort to meet the need for face shields From the Community Services activities, around 100 face shields were produced which were handed over to the hospital.

We present WireRoom , a computational framework for the intelligent design of abstract 3D wire art to depict a given 3D model. Our algorithm generates a set of 3D wire shapes from the 3D model with informative, visually pleasing, and concise structures. It is achieved by solving a dynamic travelling salesman problem on the surface of the 3D model with a multi-path expansion approach. We introduce a novel explorative computational design procedure by taking the generated wire shapes as candidates, avoiding manual design of the wire shape structure. We compare our algorithm with a baseline method and conduct a user study to investigate the usability of the framework and the quality of the produced wire shapes. The results of the comparison and user study confirm that our framework is effective for producing informative, visually pleasing, and concise wire shapes.

Three-dimensional printing is a technology in expansion in the medical field. It also presents many applications in orthopedics. Our review article aims to describe 3D printing, types of 3D printers, and its use in the orthopedic field. 3D models can be created using tomography scans. Those models can then be manipulated, even simulating surgeries. It is possible to print biomodels, which will help us understand deformities and plan surgeries. Orthopedic surgeons must be updated in these disruptive technologies that may help their daily practice. Level of Evidence V, Expert opinion. RESUMO A impressão 3D é uma tecnologia em expansão na medicina, possuindo diversas utilidades na ortopedia. O objetivo deste artigo de revisão é descrever o que é a impressão 3D, seus tipos e suas aplicações na ortopedia. Modelos em 3 dimensões podem ser criados a partir da tomografia computadorizada. Estes modelos podem ser manipulados em softwares específicos, onde inclusive cirurgias podem ser simuladas. Utilizando impressoras 3D podemos criar biomodelos que nos ajudam a compreender deformidades e planejar cirurgias. É importante que o ortopedista se mantenha atualizado nestas novas tecnologias disruptivas que podem auxiliar muito no seu dia a dia. Nível de Evidência V, Opinião do especialista.

We present a rare case of double-outlet right ventricle with pulmonary atresia and discontinuous branch pulmonary arteries supplied by bilateral ducti from a right aortic arch. To our knowledge, this is only the second documented case of double-outlet right ventricle with bilateral ducti. (Level of Difficulty: Advanced.), Central Illustration

Introduction: Numerous classifications have been developed to assess tibial plateau fractures (TPF). Of these, the Schatzker system is the most widely reported in the literature yet this system is limited in its characterisation of morphological fracture features underlying the fracture location. The purpose of this study was to compare 3D morphological features of TPFs across different Schatzker types. Methods: This study retrospectively analysed preoperative TPF imaging data to reconstruct 3D models of the fractures. Ninety-one fractures (29 female, 62 male) were analysed and classified using Schatzker. Fracture location across Schatzker types was compared based on division of the articular surface into six ‘zones’. Additionally, morphological characteristics of the fractures were compared based on fracture type, including; the number, volume and shape of the fragments. Results: Schatzker II, IV and VI fractures were most common, making up 41%, 16% and 20%, respectively. Type II fractures commonly involved both the lateral and central aspect of the tibial plateau, similarly, type IV fractures incorporated the lateral condyle in most cases. Considering the morphological metrics, statistically significant differences were observed between Schatzker types for the number of; total, articular, cortical and volumetrically significant (all P < 0.001) fragments along with the volume of both primary (P < 0.001) and secondary (P = 0.02) fragments. Discussion: Assessment of underlying fracture characteristics in addition to fracture location can serve to provide greater detail relating to fracture morphology, which has the potential to assist with both surgical decision making and assessment of postoperative outcomes. Incorporating this information as part of a hierarchical or multifactorial framework for classifying fractures may help distinguish subtle differences between fracture types that are classifiable using the most current systems. Refereed/Peer-reviewed

Educational videos are traditional means of communicating scientific findings to a broader audience. Nowadays, they are also a very common medium in distant teaching. However, creating videos using the existing software tools can be very challenging for inexperienced users. Also, the student’s engagement in standard videos is often very limited as the experience and exploration of the presented phenomena is indirect and far from being interactive. To overcome this, we propose a novel tool, called VRdeo, for creating and presenting educational material that utilizes the advantages of virtual reality (VR). Each stage of the production is represented by an operating mode, where the user acts in a predefined role. VRdeo is a versatile platform that enables tutors to immerse into the virtual scene, explore 3D models of scientific data, and record a narrated story where the tutor is an active element, represented by a virtual avatar. The recording can be exported as a virtual scene. The observers (e.g., students) can then enter such a scene where they can move around and have several options for replaying and interacting with the tutor’s story. In cases when the observer cannot use a virtual reality device, VRdeo enables to generate a traditional 2D video as well. To evaluate VRdeo, we asked several experts in diverse fields for their feedback and conducted a user study with students, which gave us valuable information about its usefulness for both creating and consuming the narrated stories.

Dental anatomy is an integrated, core fundamental dental course, which prepares students for all future clinical dental courses. This study aimed to build up an online dental learning platform of micro-computed tomography-based three-dimensional (3D) tooth models with pulp cavity, and to further evaluate its effectiveness for dental anatomy education using a cohort study. First, ninety-six extracted permanent teeth were scanned by micro-computed tomography and the enamel, dentine, and pulp cavity of each was distinguished by different grey-scale intensities using Mimics software. Three-dimensional images allowed further discrimination and insights into permanent three-rooted premolars, central tip, and dental diseases including deep caries and wedge-shaped defects. Furthermore, a second mesiobuccal canal (MB2) in maxillary permanent molar teeth and Vertucci type III root canal configuration in mandibular anterior teeth could be detected using the 3D analytical tool. A digitized 3D tooth model learning platform was implemented. Lastly, two groups of dental students were assessed to evaluate the effect of 3D models on dental anatomy education. Participants in the Digital group were allowed to use the online dental learning platform freely after class, while the participants in the Traditional group were not. Assessment quizzes showed that participants' scores improved in the Digital group with the use of the learning platform compared with scores in the Traditional group. A questionnaire survey indicated that the participants had a positive attitude towards the 3D models. Thus, adding digital 3D resources to a traditional curriculum may have a positive effect on academic achievements.

Nowadays, Double Skin Façades (DSFs) are popular technologies adopted for both new and existing buildings. Since their introduction, new configurations and materials started to be tested to improve the DSF energy behaviour and function. Such complex technologies, able to improve comfort conditions of occupied spaces and decrease building energy requirement, are strictly related to the design phase that should be carefully evaluated. The correct prediction of air fluxes inside the DSF cavity, in fact, is highly influenced by the adopted analysis hypothesis and settings. Moreover, the absence of multiple experimental campaigns and empirical validations in the sector represents the major concerns for scientists and researchers. Among the possible numerical approaches for studying DSFs, Computational Fluid Dynamics (CFD) analyses confirm to be the most suitable solution. The CFD modelling activity presented in this paper intends to compare various Double Façade configurations by adopting bi- and three-dimensional domains and different turbulence models. According to the obtained results, 2D simulations can predict airflows inside and around the DSF channel with good approximation and reasonable computational effort. Moreover, the velocity profiles estimated by the turbulence formulations are in good accordance, underling only a few slight variations in proximity to the DSF layers.

Enhancing the appearance of physical prototypes with digital elements, also known as mixed prototyping, has demonstrated to be a valuable approach in the product development process. However, the adoption is limited also due to the high time and competence required for authoring the digital contents. This paper presents a content authoring tool that aims to improve the user acceptance by reducing the specific competence required, which is needed for segmentation and UV mapping of the 3D model used to implement a mixed prototype. Part of the tasks related to 3D modelling software, in fact, has been transferred to simpler manual tasks applied onto the physical prototype. Moreover, the proposed tool can recognise these manual inputs thanks to a computer-vision algorithm and automatically manage the segmentation and UV mapping tasks, freeing time for the user in a task that otherwise would require complete engagement. To preliminarily evaluate effectiveness and potential of the tool, it has been used in a case study to build up the mixed prototype of a coffee machine. The result demonstrated that the tool can correctly segment the 3D model of a physical prototype in its relevant parts and generate their corresponding UV maps.

This review details the state of the art in research on top coal drawing mechanisms in Longwall top coal caving (LTCC) by examining the relevant literature over the last two decades. It starts with an introduction of the brief history and basic procedures of LTCC. The framework of research on the drawing mechanism, basic concepts, and some theoretical models of LTCC are detailed in sect. research framework of top coal drawing mechanism. The authors note that the Top coal drawbody (TCD), Top coal boundary (TCB) and Top coal recovery ratio (TCRR) are key factors in the drawing mechanism. The Body–boundary–ratio (BBR) research system has been the classic framework for research over the last 20 years. The modified Bergmark–Roos model, which considers the effects of the supporting rear canopy, flowing velocity of top coal, and its shape factor, is optimal for characterizing the TCD. A 3D model to describe the TCB that considers the thicknesses of the coal seam and roof strata is reviewed. In sect. physical testing and numerical simulation, the physical tests and numerical simulations in the literature are classified for ease of bibliographical review, and classic conclusions regarding the drawing mechanism of top coal are presented and discussed with elaborate illustrations and descriptions. The deflection of the TCD is noted, and is caused by the shape of the rear canopy. The inclined coal seam always induces a larger TCD, and a deflection in the TCD has also been observed in it. The effects of the drawing sequence and drawing interval on the TCRR are reviewed, where a long drawing interval is found to lead to significant loss of top coal. Its flowing behavior and velocity distribution are also presented. Sect. practical applications of drawing mechanisms for LTCC mines 4 summarizes over 10 cases where the TCRR of LTCC mines improved due to the guidance of the drawing mechanism. The final section provides a summary of the work here and some open questions. Prospective investigations are highlighted to give researchers guidance on promising issues in future research on LTCC.

The present paper focuses on the project for the Tate Modern extension by Herzog & de Meuron, and in particular on the detailing of one of its most singular elements, the brick facade. Used to control the massive amount of data coming from the existing 336,000 bricks that form the outer skin of the building, digital scripting allowed the generation of a flexible 3D model that supported the visualisation and testing of the complex geometric issues that this material brought out in the construction of the facade. Even though this parametric tool played an important part in the decision-making process, it was just one of the factors in a design methodology marked by an enriching interplay between digital technologies and analogue methods, with modelling standing at the core of the whole process.

The purpose of this in vitro study was to quantify the bone resected from the proximal femur during hip arthroscopy using metrics generated from magnetic resonance imaging (MRI) and computed tomography (CT) reconstructed three-dimensional (3D) bone models. Seven cadaveric hemi-pelvises underwent both a 1.5 T MRI and CT scan before and following an arthroscopic proximal femoral osteochondroplasty. The images from MRI and CT were segmented to generate 3D proximal femoral surface models. A validated 3D--3D registration method was used to compare surface--to--surface distances between the 3D models before and following surgery. The new metrics of maximum height, mean height, surface area and volume, were computed to quantify bone resected during osteochondroplasty. Stability of the metrics across imaging modalities was established through paired sample t--tests and bivariate correlation. Bivariate correlation analyses indicated strong correlations between all metrics (r = 0.728--0.878) computed from MRI and CT derived models. There were no differences in the MRI- and CT-based metrics used to quantify bone resected during femoral osteochondroplasty. Preoperative- and postoperative MRI and CT derived 3D bone models can be used to quantify bone resected during femoral osteochondroplasty, without significant differences between the imaging modalities.

In this paper, we derive the weak form for clamped plates composed of incompressible neo-Hookean material from the uniformly valid asymptotic plate theory. By using the finite-element software COMSOL, we study the numerical solutions of the weak form. We show the accuracy and the efficiency of the weak form by comparing the numerical results for the two-dimensional weak form and a three-dimensional model. As a basis for comparison we choose numerical values of the displacement, the second Piola–Kirchhoff stress, and the Green–Lagrange strain at the bottom. The numerical simulations are performed for three different cases of thickness–span ratios, including (1) very thin plate, (2) thin plate, and (3) moderately thick plate. The results show that the uniformly valid plate theory is a reliable and implementable plate theory for even moderately thick plates with large deformations.

Objective Aneurysm volume quantification (AVQ) using the equation of ellipsoid volume is widely used although it is inaccurate. Furthermore, AVQ with 3-dimensional (3D) rendered data has limitations in general use. A novel universal method for AVQ is introduced for any diagnostic modality and application to any shape of aneurysms. Methods Relevant AVQ studies published from January 1997 to June 2019 were identified to determine common methods of AVQ. The basic idea is to eliminate the normal artery volume from 3D model with the aneurysm. After Digital Imaging and Communications in Medicine (DICOM) data is converted and exported to stereolithography (STL) file format, the 3D STL model is modified to remove the aneurysm and the volume difference between the 3D model with/without the aneurysm is defined as the aneurysm volume. Fifty randomly selected aneurysms from DICOM database were used to validate the different AVQ methods. Results We reviewed and categorized AVQ methods in 121 studies. Approximately 60% used the ellipsoid method, while 24% used the 3D model. For 50 randomly selected aneurysms, volumes were measured using 3D Slicer, RadiAnt, and ellipsoid method. Using 3D Slicer as the reference, the ratios of mean difference to mean volume obtained by RadiAnt and ellipsoid method were -1.21±7.46% and 4.04±30.54%, respectively. The deviations between RadiAnt and 3D Slicer were small despite of aneurysm shapes, but those of ellipsoid method and 3D Slicer were large. Conclusion In spite of inaccuracy, ellipsoid method is still mostly used. We propose a novel universal method for AVQ that is valid, low cost, and easy to use.

In the future, the application of quantitative imaging and computational analysis will reduce the burden on radiologists. We herein report 8 pilot cases both with and without intrahepatic biliary stricture (IHBS) diseases which have been analyzed with the novel analytical system MRCP+ (Perspectum Ltd., Oxford, UK). The colored and well-visualized 3D models of the entire biliary trees could be obtained in all 8 cases. Three representative cases did not show dilated regions in the intrahepatic bile ducts. Cases diagnosed as a pancreatico-biliary maljunction showed slightly increased dilated visualization in the extrahepatic duct. Except in a case with severe stenosis resulting from hepatolithiasis, the number of visualized intrahepatic bile ducts tended to be decreased and the volume of biliary tree and the total length of stricture and dilatation were also decreased. However, the number of IHBS or dilatation was unchanged. The number of strictures obtained by MRCP+ and the subjective counts of stenosis from a radiologist was not found to be correlated. In a case of severe stenosis at the left lateral bile duct, the number of intrahepatic biliary dilatations was increased. The latest computerized 3D modeling technology was found to be useful in visualizing the alteration of intraluminal diameter of the entire biliary trees at a glance, which can provide the automatic diagnosis of IHBS diseases at an earlier phase.

Objectives The present study evaluated the effect of rapid maxillary expansion (RME) on the morphology of the upper airway (UA) by calculating cross-sectional areas and volumes and comparing the effect in patients with a normal-sized adenoid with the effect in patients with an enlarged adenoid. Study design: Seventeen patients met the inclusion criteria. We constructed 3D models of the UA on cone-beam computed tomography images to calculate cross-sectional areas and volumes at the levels of the nasopharyngeal, retropalatal, and retroglossal airways. Patients were divided into two groups: group 1 was comprised of patients with an adenoidal nasopharyngeal (AN) ratio < 0.6 and group 2 with an AN ratio ≥ 0.6. Paired samples t-tests assessed any area and volumetric changes of the UA after RME. Changes in degree of nasal obstruction, calculated as the AN ratio, was then compared for the two groups. An independent samples t-test compared volumetric changes in the nasopharynx between the two groups before and after RME. Results Changes in cross-sectional areas and volumes of the UA due to RME were not significant. The effects of RME on AN ratio (11 % vs 0 %) and nasopharyngeal volume (36.8 % vs 5.97%) were somewhat larger in group 2 patients who had adenoid-associated nasal obstruction compared with group 1 patients with a normal-sized adenoid; however, the differences were not significant. Conclusions After RME, the patients with an enlarged adenoid had more increases in nasopharyngeal volume compared with those with normal adenoid, despite there was no significant difference.