Telemedicine allows experts to assess patients in remote locations, enabling quality convenient, cost-effective care. To help assess foot wounds remotely, we investigated the reliability of a novel optical imaging system employing a three-dimensional camera and disposable optical marker. We first examined inter- and intraoperator measurement variability (correlation coefficient) of five clinicians examining three different wounds. Then, to assess of the system's ability to identify key clinically relevant features, we had two clinicians evaluate 20 different wounds at two centers, recording observations on a standardized form. Three other clinicians recorded their observations using only the corresponding three-dimensional images. Using the in-person assessment as the criterion standard, we assessed concordance of the remote with in-person assessments. Measurement variation of area was 3.3% for intraoperator and 11.9% for interoperator; difference in clinician opinion about wound boundary location was significant. Overall agreement for remote vs. in-person assessments was good, but was lowest on the subjective clinical assessments, e.g., value of debridement to improve healing. Limitations of imaging included inability to show certain characteristics, e.g., moistness or exudation. Clinicians gave positive feedback on visual fidelity. This pilot study showed that a clinician viewing only the three-dimensional images could accurately measure and assess a diabetic foot wound remotely.

Aims Measurement of wound size can predict healing and provide information to guide treatment. This study assesses a novel optical wound imaging system that creates a three-dimensional image of the ulcer.Methods Using a new camera-based digital system and traditional elliptical wound measurements, 36 foot ulcers from 31 patients (aged 44-94 years, median 70 years) were examined during a 12-week period at two centres. Median diabetes duration was 18 years (range 6-56 years). Seventeen percent had Type 1 diabetes, 93% had peripheral neuropathy and 57% had peripheral artery disease. Twenty-five were reviewed consecutively, resulting in 76 ulcer examinations. Median ulcer size was 94 mm 2 , with size ranging from 3.1 to 2195 mm 2 .Results Pearson, Spearman and Kendall rank coefficients showed a strong correlation (in all cases P < 0.001) between digital measurements of wounds against traditional hand-measured estimates. Intra-observer variation of wound length using digital elliptical measurement (DEM) gave a coefficient of variation of < 3.0%. Interobserver variation of wound length using DEM was < 6.5%. Variation from a standard known-size wound area was < 8.0% across 30 trials.Conclusions This study shows a strong correlation between digital and traditional measurement techniques. The system can be easily deployed in routine clinical practice, providing an objective visual record, allowing remote in-depth analysis.Diabet. Med. 26, 93-96 (2009)

We present a technique which allows capture of 3D surface geometry and a useful class of BRDFs using extremely simple equipment. A standard digital camera with an attached flash serves as a portable capture device, which may be used to sample geometry to very high resolution, as well as supplying samples over a large portion of the 4D space on which the BRDF is defined. Importantly, it allows capture of extended samples which may have spatially varying (inhomogeneous) BRDF. We demonstrate the system by capturing the geometry of complex materials with varying albedo and BRDF. We show in-situ capture of materials such as a brick wall and a human hand. The limitations of the system are that samples should be roughly planar, and that the BRDF should have some diffuse component in order that a first approximation to the normals can be computed. However, given the simplicity and ease of use of the system (it takes a few minutes to carefully capture a hand), and the ability to capture extended surfaces without any range capture device such as a laser scanner we argue that it is a valuable addition to the range of real-world BRDF capture systems in the literature. We extend standard photometric stereo techniques by moving both the camera and the light source. By incorporating automatic parallax correction we allow the capture of surfaces which are quite far from planar.

Abbreviations: (2D) two-dimensional, (3D) three-dimensional, (app) application, (EMR) electronic medical recordKeywords: diabetic foot, imaging, technology, wound healing, wounds AbstractA significant arising complication in the care of patients with diabetes is increased susceptibility to chronic wounds, including diabetic foot ulcers and pressure sores. This is driven by, e.g., neuropathy and peripheral arterial disease. It is well recognized that best practice in wound care requires wound assessment, including measurement, on presentation and regularly throughout the treatment program. Proper assessment is necessary to ensure that the most appropriate and cost-effective therapy is used at all times, with quantitative measurement necessary to track the efficacy of the chosen approach. A documented assessment can also assist patient-clinician dialog and discussion within the multidisciplinary team. Remote evaluation and assessment of the wound is also of increasing importance and practicality through the use of a telemedicine approach. There has been considerable progress in the space of imaging for wounds, including systems that include threedimensional measurement and telemedicine features. This literature review examines the available options and reviews the clinical evidence for measurement accuracy, scope for remote assessment, and published user feedback on the systems. J Diabetes Sci Technol 2013;7(5):1190-1194 SYMPOSIUMFoot ulcers are one of the most common complications of diabetes, affecting up to 25% of patients during their lifetime 1 and frequently resulting in hospitalization. 2-4Diabetic foot ulcers are also associated with significant morbidity and mortality, 5 with 80% of all diabetes-related lower extremity amputation being preceded by a foot ulcer. 6 Together with prevention strategies, proper management must be a mainstay in the approach to curbing the burden associated with foot ulcers.Accurate recognition and monitoring of ulcer characteristics facilitates benchmarking therapeutic response. Further, if research into new agents/interventions for wound healing should continue to inform practice, it is essential that ulcer characteristics are well defined in order to (i) enable comparison between studies, (ii) determine which patients/ulcers derive the most benefits from a particular therapeutic approach, and (iii) allow accurate monitoring of wound healing in order to guide clinical decision making.

Accurate and reliable tracking of the 3D position of human heads is a continuing research problem in computer vision. This paper addresses the specific problem of model-based tracking with a generic deformable 3D head model. Following the work of Vetter and Blanz, a collection of head models is obtained from a 3D scanner, registered and parameterized to give a generic head model which is linearly parameterized by a small number of parameters. This is the 3D analogue of Cootes and Taylor's active appearance models. We cast tracking as a parameter estimation problem, and note that many existing solutions to the problem-such as CONDENSATION and Kalman filtering-are analogous to nonlinear optimization strategies in numerical analysis. We show how careful analysis of the error function, parameterization of the model pose parameters, and choice of optimizer allows us to robustly track 3D head pose in digital video camera footage of quickly moving heads.