15 research outputs found
Analysis of the reproducibility of the gray values and noise of a direct digital radiography system
Radiological and histopathological evaluation of experimentally-induced periapical lesion in rats
On resolution enhancement of capillary based scanning X-ray microfluorescence spectroscopy
From Malawi to Middlesex: the case of the Arbutus Drill Cover System as an example of the cost-saving potential of frugal innovations for the UK NHS
Background Musculoskeletal disease is one of the leading clinical and economic burdens of the UK health system, and the resultant demand for orthopaedic care is only set to increase. One commonly used and one of the most expensive hardware in orthopaedic surgery is the surgical drill and saw. Given financial constraints, the National Health Service (NHS) needs an economic way to address this recurring cost. We share evidence of one frugal innovation with potential for contributing to the NHSâ efficiency saving target of ÂŁ22 billion by 2020. Methods Exploratory case study methodology was used to develop insights and understanding of the innovations potential for application in the NHS. Following a global search for potential frugal innovations in surgery, the Arbutus Drill Cover System was identified as an innovation with potential to deliver significant cost savings for the NHS in the UK. Results The Arbutus Drill Cover System is up to 94% cheaper than a standard surgical drill available in the UK. Clinical and laboratory tests show that performance, safety and usability are as good as current offerings in high-income countries and significantly better than hand drills typically used in low-and-middle-income countries. The innovation meets all regulatory requirements to be a medical device in the Europe and North America. Conclusions The innovation holds promise in reducing upfront and life span costs for core equipment used in orthopaedic surgery without loss of effectiveness or safety benchmarks. However, the innovation needs to navigate complicated and decentralised procurement processes and clinicians and healthcare leaders need to overcome cognitive bias
Hydroxyapatite granule/carrier composites promote new bone formation in cortical defects
BACKGROUND: A great deal of interest has been focused on finding substitutes for autogenous bone grafts. Among the most interesting materials are different calcium phosphate compositions (e.g., hydroxyapatite [HA]), due to their biocompatible properties in hard and soft tissue.PURPOSE: The bone response to porous ceramic HA granules in combination with two lipid and one polysaccharide carrier was evaluated in an experimental bone defect model in rabbits.MATERIALS AND METHODS: Circular defects (Ă 4 mm) were made in both tibias of 32 rabbits. The 64 defects were divided into four groups. Group A was augmented with a composite of HA granules and a phospholipid-diacetyl-glycerol carrier, group B with HA granules and a phospholipid carrier, group C received HA granules and a sodium hyaluronan carrier, and group D served as control. The animals were killed after 6 weeks and ground sections were evaluated using light microscopic morphometry. X-ray microfluorescence (XRF) was applied in order to evaluate the suitability of this method to examine bone-biomaterial interfaces. Calcium distribution was studied using x-ray fluorescence line scans at selected interface regions of two sections in group B.RESULTS: The HA/phospholipid composites were easier to shape and handle than the HA/hyaluronan composite. Group A had 36% newly formed bone area within the defect. Groups B and C showed significantly more newly formed bone within the defect (47% and 49%, respectively) compared to the control group (31%). The XRF analysis revealed that the amount of calcium in the newly formed bone was similar to that observed for the HA granules and slightly lower when compared to the mature, lamellar bone.CONCLUSIONS: Synchrotron radiation may be a new, suitable technique to study the interface between bone and biomaterials with regard to mineral content. The results suggest that HA granule/lipid and HA granule/hyaluronan composites have interesting properties as bone-substitute materials
Digital images obtained with a digital camera are not associated with a loss of critical information â a preliminary study
Digitizing radiographic films: a simple way to evaluate indirect digital images
OBJECTIVES: This study applied a simple method to evaluate the performance of three digital devices (two scanners and one digital camera) using the reproducibility of pixel values attributed to the same radiographic image. METHODS: Using the same capture parameters, a radiographic image was repeatedly digitized in order to determine the variability of pixel values given to the image throughout the digitization process. One coefficient value was obtained and was called pixel value reproducibility. RESULTS: A significant difference in pixel values was observed among the three devices for the digitized images (ANOVA, p<0.00001). There was significant pixel value variability at the same digitization conditions for one scanner and the digital camera. CONCLUSIONS: Digital devices may assign pixel values differently in consecutive digitization depending on the optical density of the radiographic image and the equipment. The pixel value reproducibility was not satisfactory as tested for two devices. It is maybe advisable knowing the digitization variations regarding pixel values whenever using digital radiography images in longitudinal clinical examinations