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This study aims to generate different three-dimensional (3D) foam models using computer tomography (CT) scan and solid continuum techniques. The generated foam models were used to study deformation mechanism and the elastic-plastic behaviour with the existing experimental foam behaviour.

CT scan model was generated by combing 2D images of foam in MIMICS software. Afterwards, it was imported in ABAQUS/CAE software. However, solid continuum model was generated in ABAQUS/CAE software by using crushable foam properties. Then, the generated foam models were sets boundary conditions for a compression test.

CT scans capture the actual morphology of foam sample which may directly an image based finite element foam model. The sectional views of both the models were used to observe deformation mechanism on compression. The real compressive behaviour of foam was visualised in CT-Scan foam model. It was observed that CT-scan model was the more accurate modelling method than crushable foam model.

The internal structure of foam is very complex and difficult to analyse. Therefore, CT-scanning may be the accurate method for capturing the macro-level detailing of foam structure. A CT-scan foam model can be used for multiple times for mechanical analysis using a simulation software, which may reduce the manufacturing and the experimental cost and time.

The topic of human skeletal analysis is a sensitive subject in North America. Laws and regulations surrounding research of human skeletal material make it difficult to use these remains to characterize various populations. Recent technology has the potential to solve this dilemma. Three-dimensional (3D) scanning creates virtual models of this material, and stores the information, allowing future studies on the material. The paper aims to discuss these issues.

To assess the potential of this methodology, the authors compared processing time, accuracy and costs of computer tomography (CT) scanner to the Artec Eva portable 3D surface scanner. Using both methodologies the authors scanned and 3D printed one adult individual. The authors hypothesize that the Artec Eva will create digital replicas of <5 percent error based on Buikstra and Ubelaker standard osteometric measurements. Error was tested by comparing the measurements of the skeletal material to the Artec data, CT data and 3D printed data.

Results show that larger bones recorded by the Artec Eva have <5 percent error of the original specimen while smaller more detailed images have >5 percent error. The CT images are closer to <5 percent accuracy, with few bones still >5 percent error. The Artec Eva scanner is inexpensive in comparison to a CT machine, but takes twice as long to process the Eva’s data. The Artec Eva is sufficient in replication of larger elements, but the CT machine is still a preferable means of skeletal replication, particularly for small elements.

This research paper is unique because it compares two common forms of digitization, which has not been done. The authors believe this paper would be of value to natural history curators and various researchers.

The purpose of this paper is to describe a novel, nanomaterial‐based X‐ray imaging technology, developed at the University of North Carolina.

The paper describes a unique X‐ray source, based on field emission from a carbon nanotube (CNT) cold cathode and discusses its application to computer tomography (CT).

CNT‐based X‐ray sources are shown to offer improved performance over conventional thermionic devices and allow the design of gantry‐free, stationary CT systems with faster scanning speeds and better image quality. The field emission technology has been commercialised by Xintek and a joint venture with Siemens, XinRay Systems, aims to commercialise CT imagers based on the technology.

The paper describes a novel approach to the generation of X‐rays and its use in medical CT imaging systems.

Computer tomography (CT) for 3D reconstruction entails a huge number of coplanar fan‐beam projections for each of a large number of 2D slice images, and excessive radiation intensities and dosages. For some applications its rate of throughput is also inadequate. A technique for overcoming these limitations is outlined.Design methodology/approach – A novel method to reconstruct 3D surface models of objects is presented, using, typically, ten, 2D projective images. These images are generated by relative motion between this set of objects and a set of ten fanbeam X‐ray sources and sensors, with their viewing axes suitably distributed in 2D angular space.Findings – The method entails a radiation dosage several orders of magnitude lower than CT, and requires far less computational power. Experimental results are given to illustrate the capability of the techniquePractical implications – The substantially lower cost of the method and, more particularly, its dramatically lower irradiation make it relevant to many applications precluded by current techniquesOriginality/value – The method can be used in many applications such as aircraft hold‐luggage screening, 3D industrial modelling and measurement, and it should also have important applications to medical diagnosis and surgery.

The purpose of this paper is to generate facsimiled rapid prototyping (RP) models for medical analysis that demands an answer about the accuracy of medical models.

The RP technology for anatomical biomodeling is the accurate RP procedure of milling and joining, a method that is used to produce high accurate functional prototypes. To fabricate medical prototypes with RP, there is a need to get appropriate data information. Along that process, image data will be taken by computer‐tomography (CT) images as data basis. The key process is to generate a digital three‐dimensional (3D) model that represents the original object as best as possible. To be able to make a statement about the accuracy of such a model the necessary parameters run along a CT scan are of interest.

A case study using a generated test model is presented in order to show the process accuracy in relation to the chosen scan parameters. The quality of editing CT images for a 3D‐reconstruction as a necessary pre‐process for RP is, to an important degree, based on the used scan parameters.

This paper represents a cutting‐edge analysis that gives answers about the constrictive accuracy that is achievable for medical RP models.

The purpose of this paper is to present a robotic motion compensation system, using ultrasound images, to assist orthopedic surgery. The robotic system can compensate for femur movements during bone drilling procedures. Although it may have other applications, the system was thought to be used in hip resurfacing (HR) prosthesis surgery to implant the initial guide tool. The system requires no fiducial markers implanted in the patient, by using only non-invasive ultrasound images.

The femur location in the operating room is obtained by processing ultrasound (USA) and computer tomography (CT) images, obtained, respectively, in the intra-operative and pre-operative scenarios. During surgery, the bone position and orientation is obtained by registration of USA and CT three-dimensional (3D) point clouds, using an optical measurement system and also passive markers attached to the USA probe and to the drill. The system description, image processing, calibration procedures and results with simulated and real experiments are presented and described to illustrate the system in operation.

The robotic system can compensate for femur movements, during bone drilling procedures. In most experiments, the update was always validated, with errors of 2 mm/4°.

The navigation system is based entirely on the information extracted from images obtained from CT pre-operatively and USA intra-operatively. Contrary to current surgical systems, it does not use any type of implant in the bone to track the femur movements.

This study aims to provide an overview of rapid prototyping (RP) and shows the potential of this technology in the field of medicine as reported in various journals and proceedings. This review article also reports three case studies from open literature where RP and associated technology have been successfully implemented in the medical field.

Key publications from the past two decades have been reviewed.

This study concludes that use of RP-built medical model facilitates the three-dimensional visualization of anatomical part, improves the quality of preoperative planning and assists in the selection of optimal surgical approach and prosthetic implants. Additionally, this technology makes the previously manual operations much faster, accurate and cheaper. The outcome based on literature review and three case studies strongly suggests that RP technology might become part of a standard protocol in the medical sector in the near future.

The article is beneficial to study the influence of RP and associated technology in the field of medicine.

This paper aims to study the influence of the binder saturation level on the accuracy and on the mechanical properties of three-dimensional (3D)-printed scaffolds for bone tissue engineering.

To study the influence of the liquid binder volume on the models accuracy, two quality test plates with different macropore sizes were designed and produced. For the mechanical and physical characterisation, cylindrical specimens were used. The models were printed using a calcium phosphate powder, which was characterised in terms of composition, particle size and morphology, by X-ray diffraction (XRD), laser diffraction and Scanning electron microscopy (SEM) analysis. The sample’s physical characterisation was made using the Archimedes method (porosity), SEM, micro-computer tomography (CT) and digital scan techniques, while the mechanical characterisation was performed by means of uniaxial compressive tests. Strength distribution was analysed using a statistical Weibull approach, and the dependence of the compressive strength on the porosity was discussed.

The saturation level is determinant for the structural characteristics, accuracy and strength the models produced by three-dimensional printing (3DP). Samples printed with the highest saturation showed higher compressive strengths (24 MPa), which are over the human trabecular bone. The models printed with lower saturations presented the highest accuracy and pore interconnectivity.

This study allowed to acquire important knowledge concerning the effects of shell/core saturation on the overall performance of the 3DP. With this information it is possible to devise scaffolds with the required properties for bone scaffold engineering.

This case study aims to demonstrate the strengths of the Lean Six Sigma (LSS) methodology to improve the acute ischemic stroke (AIS) treatment rates and reduce process lead time at Baruch Padeh Medical Center (BPMC), a rural hospital in the Galilee region of Northern Israel. The LSS project redefined the BPMC stroke care pathway and increased its efficacy.

The LSS methodology was implemented in September 2017 by integrating lean principles and the Six Sigma DMAIC (Define–Measure–Analyze–Improve–Control). Existing procedures, field observation, ad hoc measurement and in-depth interviews were utilized, and the GEMBA method was implemented to identify root cause and improve actions optimizing the stroke pathway.

The presented case shows the usefulness of the LSS methodology in improving quality performance in a rural hospital. The intervention allowed the BPMC to improve the intravenous tissue plasminogen activator (IV-tPA) administration rate (+15.2%), reducing the process lead time. The lead time of door-to-computer tomography decreased from 52 to 26 min, and the door-to-needle time decreased from 94 to 75 min.

The present case study shows the implementation of the LSS methodology aimed to improve the IV-tPA administration rate and reduce the stroke pathway lead time in a rural hospital. The case demonstrates the potential for the LSS methodology to support the AIS pathway optimization and represents a guide for healthcare organizations located in rural areas.

In plastic reconstruction surgeries, total auricular reconstruction for microtia is a real challenge. Presently, autogenous costal cartilage and MEDPOR are the chosen materials but none can satisfy the requirements of orthopaedic operation. The purpose of this paper is to examine how to fabricate an ear scaffold with a good shape.

A new approach to form the auricle framework is described. CT scan data of the patient's contralateral “good ear” are used to generate a 3D reconstruction model of the new ear. This model is then imported into rapid prototyping (RP) software to slice. The sliced data drive the fused deposition modeling (FDM) machine to build the ear framework layer by layer. Based on the actual shape of the computer model, FDM technology produces a real feel ear framework to match the size of the opposite good ear.

An artificial human ear was built using FDM technology based on CT images. The auricular framework with polyurethane was a porous structure with good flexibility and biocompatibility. After implanting into the mouse, a real life human ear appeared on the back of the mouse. The experiment indicated that this method provided an efficient way to macrotia reconstruction.

The freeform fabrication technique combined with CT image reconstruction could provide an efficient way to produce a porous structure and solve the framework carving problem in microtia reconstruction.