Utility of 3D modelling of the patient's living environment as perceived by occupational therapists.

INTRODUCTION: Visiting a patient's living environment is important for occupational therapists, albeit costly and time consuming. MapIt is a mobile app producing a 3D representation of a home with the possibility of taking measurements. The purpose of this study was to explore the utility of a 3D representation of a patient's home for the clinical practice of occupational therapists. METHODS: Case study in which the unit of analysis was the utility of MapIt as defined by ISO 9241-11:2018 and as perceived by occupational therapists in four different occupational therapy clinical settings (Canada). Onsite observations with 10 occupational therapists (and their patients) were triangulated with data from interviews, diaries, and logbooks. Inductive thematic condensation led to emerging conclusions for each clinical setting, fuelling the next case data collection and analysis. Inter-case analysis was corroborated by additional occupational therapists, through crowdsourcing and expert review. RESULTS: Occupational therapists' clinical reasoning was supported by the MapIt app, enhancing and streamlining their work and inducing adjustments to treatment plans. Occupational therapists saw and measured the patient's environment remotely, to better match person-environment-occupation and promote occupational engagement. MapIt's 3D representations were judged useful to communicate between occupational therapists and stakeholders, to educate, allow continuity, optimise resources, minimise the patient's time on a waitlist for homecare, and save time for everyone. DISCUSSION: MapIt allowed occupational therapists who performed home visits to bring a little of the patients' home to their office, whereas occupational therapists without access to the home could see it and take measurements. MapIt's utility was confirmed for practice in clinical settings and for better continuity of care between settings. CONCLUSION: MapIt makes it possible for occupational therapists to 'walk around' the patient's home remotely, but the possibility of measuring environmental elements is a 3D model's true added value over currently used photos or short videos.

A workflow for the creation of photorealistic 3D cadaveric models using photogrammetry.

Three-dimensional (3D) representations of anatomical specimens are increasingly used as learning resources. Photogrammetry is a well-established technique that can be used to generate 3D models and has only been recently applied to produce visualisations of cadaveric specimens. This study has developed a semi-standardised photogrammetry workflow to produce photorealistic models of human specimens. Eight specimens, each with unique anatomical characteristics, were successfully digitised into interactive 3D models using the described workflow and the strengths and limitations of the technique are described. Various tissue types were reconstructed with apparent preservation of geometry and texture which visually resembled the original specimen. Using this workflow, an institution could digitise their existing cadaveric resources, facilitating the delivery of novel educational experiences.

The SARS-CoV-2 Spike Protein Mutation Explorer: using an interactive application to improve the public understanding of SARS-CoV-2 variants of concern.

Due to the COVID-19 pandemic the virus responsible, SARS-CoV-2, became a source of intense interest for non-expert audiences. The viral spike protein gained particular public interest as the main target for protective immune responses, including those elicited by vaccines. The rapid evolution of SARS-CoV-2 resulted in variations in the spike that enhanced transmissibility or weakened vaccine protection. This created new variants of concern (VOCs). The emergence of VOCs was studied using viral sequence data which was shared through portals such as the online Mutation Explorer of the COVID-19 Genomics UK consortium (COG-UK/ME). This was designed for an expert audience, but the information it contained could be of general interest if suitably communicated. Visualisations, interactivity and animation can improve engagement and understanding of molecular biology topics, and so we developed a graphical educational resource, the SARS-CoV-2 Spike Protein Mutation Explorer (SSPME), which used interactive 3D molecular models and animations to explain the molecular biology underpinning VOCs. User testing showed that the SSPME had better usability and improved participant knowledge confidence and knowledge acquisition compared to COG-UK/ME. This demonstrates how interactive visualisations can be used for effective molecular biology communication, as well as improving the public understanding of SARS-CoV-2 VOCs.

Pores, Pimples and Pathologies: 3D Capture and Detailing of the Human Skin for 3D Medical Visualisation and Fabrication.

Three-dimensional (3D) scanning of the human skin for 3D medical visualisation and printing does not often produce the desired results due to a number of factors including the specularity of human skin, difficulties in scanning fine structures such as the hair and the capabilities of the scanning technologies utilised. Some additional 3D modelling may be required to make the surfaces more suitable for use in the production of anatomical and medical teaching resources, computerised facial depiction and design of bespoke prostheses. Three-dimensional scanned surfaces can be enhanced through digital sculpting and embossing of high-resolution photographs of the human skin.

Combination therapy of three-dimensional (3D) visualisation operative treatment planning system and US-guided percutaneous microwave ablation in larger renal cell carcinomas (D ≥ 4 cm): preliminary results.

PURPOSE: To analyse the clinical outcomes of combination therapy of three-dimensional (3D) visualisation operative treatment planning system and US-guided percutaneous microwave ablation (PMWA) in larger renal cell carcinomas (RCCs) (D ≥ 4 cm). MATERIALS AND METHODS: The results from 20 patients with 20 larger RCCs treated with a 3D visualisation operative treatment planning system and US-guided PMWA were reviewed retrospectively. The patients were followed up by contrast-enhanced images at 1, 3, and 6 months and every 6 months thereafter. The outcomes of overall survival and local tumour progression rate were statistically analysed. RESULTS: The median follow-up period was 26 months. The mean time of ablation for one tumour was 1.1 ± 0.3 sessions. The average number of ablation points of one tumour was 4.5 ± 0.9. The mean output power of ablation was 50.50 ± 2.2 W. The mean time of ablation for one tumour was 1374.4 ± 391.1 s. Artificial ascites was used in 12 (60%) tumours adjacent to the intestinal tract, and thermal monitoring system was used in all tumours (100%). Technical effectiveness and metastasis-free status were achieved in all tumours. The 1- and 2-year local tumour progression rates were both 5%. The cancer-specific survival rate and 2-year overall survival rates were both 100%. No severe major complications occurred. There was no significant difference in creatinine or urea nitrogen before or 3 days after ablation. CONCLUSIONS: Combination therapy of 3D visualisation operative treatment planning system and US-guided PMWA appeared to be a safe and effective technique for the management of larger RCCs, which could improve clinical efficacy.

The horizontal plane appearances of scoliosis: what information can be obtained from top-view images?

PURPOSE: A posterior-anterior vertebral vector is proposed to facilitate visualization and understanding of scoliosis. The aim of this study was to highlight the interest of using vertebral vectors, especially in the horizontal plane, in clinical practice. METHODS: We used an EOS two-/three-dimensional (2D/3D) system and its sterEOS 3D software for 3D reconstruction of 139 normal and 814 scoliotic spines-of which 95 cases were analyzed pre-operatively and post-operatively, as well. Vertebral vectors were generated for each case. Vertebral vectors have starting points in the middle of the interpedicular segment, while they are parallel to the upper plate, ending in the middle of the segment joining the anterior end plates points, thus defining the posterior-anterior axis of vertebrae. To illustrate what information could be obtained from vertebral vector-based top-view images, representative cases of a normal spine and a thoracic scoliosis are presented. RESULTS: For a normal spine, vector projections in the transverse plane are aligned with the posterior-anterior anatomical axis. For a scoliotic spine, vector projections in the horizontal plane provide information on the lateral decompensation of the spine and the lateral displacement of vertebrae. In the horizontal plane view, vertebral rotation and projections of the sagittal curves can also be analyzed simultaneously. CONCLUSIONS: The use of posterior-anterior vertebral vector facilitates the understanding of the 3D nature of scoliosis. The approach used is simple. These results are sufficient for a first visual analysis furnishing significant clinical information in all three anatomical planes. This visualization represents a reasonable compromise between mathematical purity and practical use.

Longitudinal three-dimensional visualisation of autoimmune diabetes by functional optical coherence imaging.

AIMS/HYPOTHESIS: It is generally accepted that structural and functional quantitative imaging of individual islets would be beneficial to elucidate the pathogenesis of type 1 diabetes. We here introduce functional optical coherence imaging (FOCI) for fast, label-free monitoring of beta cell destruction and associated alterations of islet vascularisation. METHODS: NOD mouse and human islets transplanted into the anterior chamber of the eye (ACE) were imaged with FOCI, in which the optical contrast of FOCI is based on intrinsic variations of the index of refraction resulting in a faster tomographic acquisition. In addition, the phase sensitivity allows simultaneous label-free acquisition of vascularisation. RESULTS: We demonstrate that FOCI allows longitudinal quantification of progressive autoimmune insulitis, including the three-dimensional quantification of beta cell volume, inflammation and vascularisation. The substantially increased backscattering of islets is dominated by the insulin-zinc nanocrystals in the beta cell granules. This translates into a high specificity for the functional beta cell volume of islets. Applying FOCI to a spontaneous mouse model of type 1 diabetes, we quantify the modifications of the pancreatic microvasculature accompanying the progression of diabetes and reveal a strong correlation between increasing insulitis and density of the vascular network of the islet. CONCLUSIONS/INTERPRETATION: FOCI provides a novel imaging technique for investigating functional and structural diabetes-induced alterations of the islets. The label-free detection of beta cell volume and infiltration together with vascularisation offers a unique extension to study ACE-transplanted human islets. These results are contributing to a deeper understanding of human islet transplant rejection and label-free in vivo monitoring of drug efficacy.

Computed tomography-based three-dimensional visualisation of bone corridors and trajectories for screws in open reduction and internal fixation of symphysis diastasis: a retrospective radiological study.

INTRODUCTION: Typical stabilisation of pelvic open book injuries consists of plate fixation of the symphysis. No previous literature has been published about the evaluation of screw placement and their trajectory with four oblique 4.5 mm screws using a four-hole plate in symphysis diastasis. The aim of this study was to define insertion points and angles of trajectory for crossed screw placement regardless of any plate design based on an analysis of three-dimensional computed tomography data sets. METHODS: One hundred human pelvic CT data sets were collected. Unilateral and bilateral placements of crossed 4.5 mm screws were simulated. Primary outcome measure was successful simulated screw placement without cortical breach. Secondary outcome measures included the anatomical measurements of the screw positions. RESULTS: Simulated screw placement of two oblique screws on each side of the pubic symphysis without cortical breach was achieved in all (100 %) cases. There were a total of 400 screw simulations. Medial screws were longer, lateral screws had higher coronal angles, and the distance between both screws was higher on the right side (p < 0.001 each). The lengths of the right lateral, right medial, left lateral, and left medial screws were 44.9, 65.8, 45.4, and 67.4 mm, respectively. The sagittal angles to the dorsal surface area of the pubic rami were 10.5°, 11.1°, 9.0°, and 11.0°. The coronal angles to the vertical axis of the symphysis measured 39.5°, 16.0°, 33.8°, and 16.8°. The distances between these screws and the medial edge of the pubic crest were 33.5, 8.6, 29.5, and 7.3 mm. Furthermore, certain sex- and side-related differences were noted. CONCLUSIONS: This series provides results about the feasibility and a detailed anatomical description of crossed screw placement. This is of special interest in pelvic surgery for choosing the entry points, safe screw channel parameters, and trajectories.

The evaluation of vasculature in post-mortem angio-computed tomography for anatomy research purposes: method description based on celiac trunk analysis.

BACKGROUND: Anatomical research based on deceased body specimens is a time-consuming process that requires a great deal of skill and time to perform correctly. Three-dimensional medical image analysis is an excellent tool for anatomic evaluation, but it often includes patients with comorbidities in the study group, which can skew the results. The purpose of this study was to develop and evaluate methods for anatomic research based on postmortem contrast-enhanced computed tomography angiography 3D reconstruction of the celiac trunk. MATERIALS AND METHODS: Postmortem contrast-enhanced computed tomography angiography of 105 (28.6% female, age 50.8±18.7) decedents without abdominal trauma or tumor was analyzed. The abdominal portion of the aorta and the celiac trunk with its branches were reconstructed and evaluated. The type of celiac trunk was evaluated. The results were analyzed. RESULTS: The celiac trunk, splenic artery, and common hepatic artery were visualized in all cases. The left gastric artery was visible in 97.1% of cases. The dorsal pancreatic artery was visualized in 61.0% of cases. The most common type of celiac trunk was 1 (88.6%), and the rarest types were 2, 3, and 6 (1.0%). We observed 4 morphologies of the truncus celiacus that did not fit the classification presented previously. CONCLUSIONS: This study has demonstrated that three-dimensional reconstruction of postmortem contrast-enhanced computed tomography is an excellent tool for performing accurate morphometric analyzes for anatomic research purposes. This method can serve as a source for anatomic studies in the healthy population.

Computed 3D visualisation of an extinct cephalopod using computer tomographs.

The first 3D visualisation of a heteromorph cephalopod species from the Southern Alps (Dolomites, northern Italy) is presented. Computed tomography, palaeontological data and 3D reconstructions were included in the production of a movie, which shows a life reconstruction of the extinct organism. This detailed reconstruction is according to the current knowledge of the shape and mode of life as well as habitat of this animal. The results are based on the most complete shell known thus far of the genus Dissimilites. Object-based combined analyses from computed tomography and various computed 3D facility programmes help to understand morphological details as well as their ontogentical changes in fossil material. In this study, an additional goal was to show changes in locomotion during different ontogenetic phases of such fossil, marine shell-bearing animals (ammonoids). Hence, the presented models and tools can serve as starting points for discussions on morphology and locomotion of extinct cephalopods in general, and of the genus Dissimilites in particular. The heteromorph ammonoid genus Dissimilites is interpreted here as an active swimmer of the Tethyan Ocean. This study portrays non-destructive methods of 3D visualisation applied on palaeontological material, starting with computed tomography resulting in animated, high-quality video clips. The here presented 3D geometrical models and animation, which are based on palaeontological material, demonstrate the wide range of applications, analytical techniques and also outline possible limitations of 3D models in earth sciences and palaeontology. The realistic 3D models and motion pictures can easily be shared amongst palaeontologists. Data, images and short clips can be discussed online and, if necessary, adapted in morphological details and motion-style to better represent the cephalopod animal.

Nanoscape, a data-driven 3D real-time interactive virtual cell environment.

Our understanding of cellular and structural biology has reached unprecedented levels of detail, and computer visualisation techniques can be used to create three-dimensional (3D) representations of cells and their environment that are useful in both teaching and research. However, extracting and integrating the relevant scientific data, and then presenting them in an effective way, can pose substantial computational and aesthetic challenges. Here we report how computer artists, experts in computer graphics and cell biologists have collaborated to produce a tool called Nanoscape that allows users to explore and interact with 3D representations of cells and their environment that are both scientifically accurate and visually appealing. We believe that using Nanoscape as an immersive learning application will lead to an improved understanding of the complexities of cellular scales, densities and interactions compared with traditional learning modalities.

The accuracy and precision of body mass estimation in non-avian dinosaurs.

Inferring the body mass of fossil taxa, such as non-avian dinosaurs, provides a powerful tool for interpreting physiological and ecological properties, as well as the ability to study these traits through deep time and within a macroevolutionary context. As a result, over the past 100 years a number of studies advanced methods for estimating mass in dinosaurs and other extinct taxa. These methods can be categorized into two major approaches: volumetric-density (VD) and extant-scaling (ES). The former receives the most attention in non-avian dinosaurs and advanced appreciably over the last century: from initial physical scale models to three-dimensional (3D) virtual techniques that utilize scanned data obtained from entire skeletons. The ES approach is most commonly applied to extinct members of crown clades but some equations are proposed and utilized in non-avian dinosaurs. Because both approaches share a common goal, they are often viewed in opposition to one another. However, current palaeobiological research problems are often approach specific and, therefore, the decision to utilize a VD or ES approach is largely question dependent. In general, biomechanical and physiological studies benefit from the full-body reconstruction provided through a VD approach, whereas large-scale evolutionary and ecological studies require the extensive data sets afforded by an ES approach. This study summarizes both approaches to body mass estimation in stem-group taxa, specifically non-avian dinosaurs, and provides a comparative quantitative framework to reciprocally illuminate and corroborate VD and ES approaches. The results indicate that mass estimates are largely consistent between approaches: 73% of VD reconstructions occur within the expected 95% prediction intervals of the ES relationship. However, almost three quarters of outliers occur below the lower 95% prediction interval, indicating that VD mass estimates are, on average, lower than would be expected given their stylopodial circumferences. Inconsistencies (high residual and per cent prediction deviation values) are recovered to a varying degree among all major dinosaurian clades along with an overall tendency for larger deviations between approaches among small-bodied taxa. Nonetheless, our results indicate a strong corroboration between recent iterations of the VD approach based on 3D specimen scans suggesting that our current understanding of size in dinosaurs, and hence its biological correlates, has improved over time. We advance that VD and ES approaches have fundamentally (metrically) different advantages and, hence, the comparative framework used and advocated here combines the accuracy afforded by ES with the precision provided by VD and permits the rapid identification of discrepancies with the potential to open new areas of discussion.

Application of macro photography in dental materials science.

OBJECTIVES: The goal of this study was to show the potential of the inexpensive macro photography technique for application in various fields of contemporary dental materials science. The method was used for studying surface characteristics for fractographic evaluation, topography analysis, and for the measurement of optical properties such as translucency and opalescence. MATERIALS AND METHODS: The variable test setup consisted of a digital camera with macro or microscopic objectives (combined with a lens tube and an objective adapter). The distance between object surface and objectives was controlled by an automatic stacking unit with a software-controlled mobile object slide. The exposure was carried out by LED light sources and a standard illuminant (D55). RESULTS: Highly resolved pictures with fine details, high focal depth, flexible imaging by adjusting the illuminates in different angles, and the possibility of 3D topography imaging are the main reasons why macro photography proved to be a suitable imaging method for fractographic analyses. The automatic focal stacking technique was a powerful tool for imaging distinct topographies in high-resolution with nearly unlimited focal depth and 3D surface visualisation. Translucency as well as opalescence, measured with the macro photography produced differed from the measurements performed with a conventional spectrophotometer. CONCLUSIONS: The modular structure of the cost-effective macro photography setup enables diverse applications such as identification of material groups, fractography analysis, and 3D surface visualisation. Quantification of colour, translucency, as well as opalescence under condition of the microscopic scale requires further research.

[Not Available].

UNLABELLED: Laparoscopy requires the development of technical skills distinct from those used in open procedures. Several factors extending the learning curve of laparoscopy include ergonomic and technical difficulties, such as the fulcrum effect and limited degrees of freedom. This study aimed to establish the impact of four variables on performance of two simulated laparoscopic tasks. METHODS: Six subjects including novice (n=2), intermediate (n=2) and expert surgeons completed two tasks: 1) four running sutures, 2) simple suture followed by surgeon's knot plus four square knots. Task variables were suturing angle (left/right), needle holder type (standard/articulating) and visualisation (2D/3D). Each task with a given set of variables was completed twice in random order. The endpoints included suturing task completion time, average and maximum distance from marks and knot tying task completion time. RESULTS: Suturing task completion time was prolonged by 45-degree right angle suturing, articulating needle holder use and lower skill levels (all P < 0.0001). Accuracy also decreased with articulating needle holder use (both P < 0.0001). 3D vision affected only maximum distance (P=0.0108). For the knot tying task, completion time was greater with 45-degree right angle suturing (P=0.0015), articulating needle holder use (P < 0.0001), 3D vision (P=0.0014) and novice skill level (P=0.0003). Participants felt that 3D visualisation offered subjective advantages during training. CONCLUSIONS: Results suggest construct validity. A 3D personal head display and articulating needle holder do not immediately improve task completion times or accuracy and may increase the training burden of laparoscopic suturing and knot tying.

Unveiling the invisible: mathematical methods for restoring and interpreting illuminated manuscripts.

The last 50 years have seen an impressive development of mathematical methods for the analysis and processing of digital images, mostly in the context of photography, biomedical imaging and various forms of engineering. The arts have been mostly overlooked in this process, apart from a few exceptional works in the last 10 years. With the rapid emergence of digitisation in the arts, however, the arts domain is becoming increasingly receptive to digital image processing methods and the importance of paying attention to this therefore increases. In this paper we discuss a range of mathematical methods for digital image restoration and digital visualisation for illuminated manuscripts. The latter provide an interesting opportunity for digital manipulation because they traditionally remain physically untouched. At the same time they also serve as an example for the possibilities mathematics and digital restoration offer as a generic and objective toolkit for the arts.

Validation of a Magnetic Resonance Imaging-based Auto-contouring Software Tool for Gross Tumour Delineation in Head and Neck Cancer Radiotherapy Planning.

AIMS: To carry out statistical validation of a newly developed magnetic resonance imaging (MRI) auto-contouring software tool for gross tumour volume (GTV) delineation in head and neck tumours to assist in radiotherapy planning. MATERIALS AND METHODS: Axial MRI baseline scans were obtained for 10 oropharyngeal and laryngeal cancer patients. GTV was present on 102 axial slices and auto-contoured using the modified fuzzy c-means clustering integrated with the level set method (FCLSM). Peer-reviewed (C-gold) manual contours were used as the reference standard to validate auto-contoured GTVs (C-auto) and mean manual contours (C-manual) from two expert clinicians (C1 and C2). Multiple geometric metrics, including the Dice similarity coefficient (DSC), were used for quantitative validation. A DSC≥0.7 was deemed acceptable. Inter- and intra-variabilities among the manual contours were also validated. The two-dimensional contours were then reconstructed in three dimensions for GTV volume calculation, comparison and three-dimensional visualisation. RESULTS: The mean DSC between C-gold and C-auto was 0.79. The mean DSC between C-gold and C-manual was 0.79 and that between C1 and C2 was 0.80. The average time for GTV auto-contouring per patient was 8 min (range 6-13 min; mean 45 s per axial slice) compared with 15 min (range 6-23 min; mean 88 s per axial slice) for C1. The average volume concordance between C-gold and C-auto volumes was 86.51% compared with 74.16% between C-gold and C-manual. The average volume concordance between C1 and C2 volumes was 86.82%. CONCLUSIONS: This newly designed MRI-based auto-contouring software tool shows initial acceptable results in GTV delineation of oropharyngeal and laryngeal tumours using FCLSM. This auto-contouring software tool may help reduce inter- and intra-variability and can assist clinical oncologists with time-consuming, complex radiotherapy planning.

Micro-CTvlab: A web based virtual gallery of biological specimens using X-ray microtomography (micro-CT).

BACKGROUND: During recent years, X-ray microtomography (micro-CT) has seen an increasing use in biological research areas, such as functional morphology, taxonomy, evolutionary biology and developmental research. Micro-CT is a technology which uses X-rays to create sub-micron resolution images of external and internal features of specimens. These images can then be rendered in a three-dimensional space and used for qualitative and quantitative 3D analyses. However, the online exploration and dissemination of micro-CT datasets are rarely made available to the public due to their large size and a lack of dedicated online platforms for the interactive manipulation of 3D data. Here, the development of a virtual micro-CT laboratory (Micro-CTvlab) is described, which can be used by everyone who is interested in digitisation methods and biological collections and aims at making the micro-CT data exploration of natural history specimens freely available over the internet. NEW INFORMATION: The Micro-CTvlab offers to the user virtual image galleries of various taxa which can be displayed and downloaded through a web application. With a few clicks, accurate, detailed and three-dimensional models of species can be studied and virtually dissected without destroying the actual specimen. The data and functions of the Micro-CTvlab can be accessed either on a normal computer or through a dedicated version for mobile devices.

Neural and endocranial anatomy of Triassic phytosaurian reptiles and convergence with fossil and modern crocodylians.

Phytosaurs are a clade of large, carnivorous pseudosuchian archosaurs from the Late Triassic with a near cosmopolitan distribution. Their superficial resemblance to longirostrine (long-snouted) crocodylians, such as gharials, has often been used in the past to infer ecological and behavioural convergence between the two groups. Although more than thirty species of phytosaur are currently recognised, little is known about the endocranial anatomy of this clade. Here, we describe the endocranial anatomy (including the brain, inner ear, neurovascular structures and sinus systems) of the two non-mystriosuchine phytosaurs Parasuchus angustifrons (="Paleorhinus angustifrons") and Ebrachosuchus neukami from the Late Triassic of Germany based on digital reconstructions. Results show that the endocasts of both taxa are very similar to each other in their rostrocaudally elongate morphology, with long olfactory tracts, weakly demarcated cerebral regions and dorsoventrally short endosseous labyrinths. In addition, several sinuses, including large antorbital sinuses and prominent dural venous sinuses, were reconstructed. Comparisons with the endocranial anatomy of derived phytosaurs indicate that Phytosauria is united by the presence of elongate olfactory tracts and longitudinally arranged brain architecture-characters which are also shared with Crocodyliformes. However, a substantial morphological variability is observed in the cephalic and pontine flexure and the presence of a pineal organ across the different phytosaur species. These results suggest that the endocranial anatomy in Phytosauria generally follows a plesiomorphic pattern, with moderate variation within the clade likely resulting from divergent sensory and behavioural adaptations.

Visualising gait symmetry/asymmetry from acceleration data.

Accelerometry-based quantification of gait symmetry/asymmetry is a promising approach for objectively evaluating gait dysfunctions. An important step in the application of this method in clinical settings is to develop reliable gait asymmetry measures and tools for visualising them to create easy-to-understand presentations for both clinicians and patients. This paper describes a new self-adaptive algorithm for estimating motion trajectory from acceleration data and visualising the degree of its asymmetry in 3D space. Two new parameters are introduced to capture asymmetric walking patterns based on the assessment of 3D autocorrelation and biphasicity of the motion trajectory. The performance of our algorithm is confirmed by analysing gait data collected from 245 healthy subjects. The proposed method may be clinically useful in tracking the process of recovering from pathology or injury after rehabilitation.

Studying the microanatomy of the heart in three dimensions: a practical update.

The structure and function of the heart needs to be understood in three dimensions. We give a brief historical summary of the methods by which such an understanding has been sought, and some practical details of the relatively new technique of micro-CT with iodine contrast enhancement in samples from rat and rabbit. We discuss how the improved anatomical detail available in fixed cadaveric hearts will enhance our ability to model and to understand the integrated function of the cardiomyocytes, conducting tissues, and fibrous supporting structures that generate the pumping function of the heart.