Tomografia computadorizada quantitativa periférica de alta resolução para avaliação de parâmetros morfológicos e funcionais ósseos

Abstract

High resolution peripheral quantitative computed tomography (HR-pQCT) is a new technology commercially available for less than 10 years that allows performing in vivo assessment of bone parameters. HR-pQCT assesses the trabecular thickness, trabecular separation, trabecular number and connectivity density and, in addition, cortical bone density and thickness and total bone volume and density in high-definition mode, which additionally allows obtaining digital constructs of bone microarchitecture. The application of mathematics to captured data, a method called finite element analysis (FEA), allows the estimation of the physical properties of the tissue, simulating supported loads in a non-invasive way. Thus, HR-pQCT simultaneously acquires data previously provided separately by dual energy x-ray absorptiometry (DXA), magnetic resonance imaging and histomorphometry, aggregating biomechanical estimates previously only possible in extracted tissues. This method has a satisfactory reproducibility, with coefficients of variation rarely exceeding 3%. Regarding accuracy, the method shows a fair to good agreement (r(2) = 0.37-0.97). The main clinical application of this method is in the quantification and monitoring of metabolic bone disorders, more fully evaluating bone strength and fracture risk. In rheumatoid arthritis patients, this allows gauging the number and size of erosions and cysts, in addition to joint space. In osteoarthritis, it is possible to characterize the bone marrow edema-like areas that show a correlation with cartilage breakdown. Given its high cost, HR-pQCT is still a research tool, but the high resolution and efficiency of this method reveal advantages over the methods currently used for bone assessment, with a potential to become an important tool in clinical practice.

Bone quality evaluation of experimental osteometabolic disease in Pantanal alligators (Caiman yacare) by High Resolution Computerized Microtomography (μCT)

“…Computerized microtomography is a modern laboratory methodology considered the gold standard examination for bone quality assessment (composition, resistance, and geometry) that also allows understanding etiopathology of diseases (Compston 2006, Vasilić et al 2009, Bouxsein et al 2010, Liu et al 2011, Ritman 2011, Syahrom et al 2011, Gregor et al 2012, Blok et al 2013, Cesar et al 2013, Paolillo 2013, Fernandes 2014, Paolillo et al 2014, Fuller et al 2015. Total porosity (Po (tot), %)of trabecular bone of groups G1, G2, G3, and G4 for Pantanal alligator (Caiman yacare) tibia.…”

“…Computerized microtomography (μCT) is one assessment system widely used in bone evaluation (Ritman 2011, Syahrom et al 2011, Blok et al 2013, Cesar et al 2013, Paolillo 2013, Fernandes 2014, Paolillo et al 2014, and it is considered the gold standard examination for this purpose (Bouxsein et al 2010, Fuller et al 2015. Results from this exam are based on quantitative parameters for both cortical and trabecular bone (Klinck et al 2008).…”

“…Manufacturers develop software according to their own algorithms which generate different results between companies for the same parameters (Bouxsein et al 2010). They refer to morphometric units: trabeculae (trabecular bone) with the definition of shape, number, volume, density, separation, number of connections in between, the average thickness, and the estimate force and resistance; related to the osteon (cortical bone) by measuring porosity and the definition of pore profile as open and closed (Bouxsein et al 2010, Fuller et al 2015.…”

Imaging aspects of Camurati-Engelmann disease

“…8 MRI is as effective as computerized tomography for demonstrating the hyperostotic bone, and the compressive effect on specific cranial nerves (mainly II, VII and VIII) can be characterized well. 2 Perhaps in the near future techniques such as high resolution peripheral quantitative computed tomography (HR-pQCT) 9 could provide additional information.…”

Patient-Specific Bone Multiscale Modelling, Fracture Simulation and Risk Analysis—A Survey

“…The reviewed literature features a certain confusion between the usage of HR-pCT and µCT terminologies [161]. For instance, it could be argued that [159,162] misplaces terminology.…”