RESUMEN
The challenging problem of computational bioimage analysis receives growing attention from life sciences. Fluorescence microscopy is capable of simultaneously visualizing multiple molecules by staining with different fluorescent dyes. In the analysis of the result multichannel images, segmentation of ROIs resembles only a first step which must be followed by a second step towards the analysis of the ROI's signals in the different channels. In this paper we present a system that combines image segmentation and information visualization principles for an integrated analysis of fluorescence micrographs of tissue samples. The analysis aims at the detection and annotation of cells of the Islets of Langerhans and the whole pancreas, which is of great importance in diabetes studies and in the search for new anti-diabetes treatments. The system operates with two modules. The automatic annotation module applies supervised machine learning for cell detection and segmentation. The second information visualization module can be used for an interactive classification and visualization of cell types following the link-and-brush principle for filtering. We can compare the results obtained with our system with results obtained manually by an expert, who evaluated a set of example images three times to account for his intra-observer variance. The comparison shows that using our system the images can be evaluated with high accuracy which allows a considerable speed up of the time-consuming evaluation process.
Asunto(s)
Células del Tejido Conectivo/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador , Microscopía Fluorescente , Páncreas/diagnóstico por imagen , Semántica , Células del Tejido Conectivo/clasificación , Humanos , Reconocimiento de Normas Patrones Automatizadas , RadiografíaRESUMEN
INTRODUCTION: Ultrasound is widely used for imaging purposes and as an adjunct to physiotherapy. Low-intensity pulsed ultrasound (LIPUS), having removed the thermal component found at higher intensities, is used to improve bone healing. However, its potential role in soft-tissue healing is still under investigation. MATERIAL AND METHODS: We searched on Medline using the keywords: low-intensity pulsed ultrasound, LIPUS and LIPUS and soft-tissue healing. Thirty-two suitable articles were identified. RESULTS: Research, mainly pre-clinical, so far has shown encouraging result, with LIPUS able to promote healing in various soft tissues such as cartilage, inter-vertebral disc, etc. The effect on the bone-tendon junction, however, is primarily on bone. The role of LIPUS in treating tendinopathies is questionable. Adequately powered human studies with standardisation of intensities and dosages of LIPUS for each target tissue are needed.
Asunto(s)
Células del Tejido Conectivo/diagnóstico por imagen , Traumatismos de los Tejidos Blandos/diagnóstico por imagen , Terapia por Ultrasonido/métodos , Ultrasonografía Doppler de Pulso/métodos , Humanos , Resultado del Tratamiento , Terapia por Ultrasonido/economíaRESUMEN
BACKGROUND: In humans, connective tissue forms a complex, interconnected network throughout the body that may have mechanosensory, regulatory and signaling functions. Understanding these potentially important phenomena requires non-invasive measurements of collagen network structure that can be performed in live animals or humans. The goal of this study was to show that ultrasound can be used to quantify dynamic changes in local connective tissue structure in vivo. We first performed combined ultrasound and histology examinations of the same tissue in two subjects undergoing surgery: in one subject, we examined the relationship of ultrasound to histological images in three dimensions; in the other, we examined the effect of a localized tissue perturbation using a previously developed robotic acupuncture needling technique. In ten additional non-surgical subjects, we quantified changes in tissue spatial organization over time during needle rotation vs. no rotation using ultrasound and semi-variogram analyses. RESULTS: 3-D renditions of ultrasound images showed longitudinal echogenic sheets that matched with collagenous sheets seen in histological preparations. Rank correlations between serial 2-D ultrasound and corresponding histology images resulted in high positive correlations for semi-variogram ranges computed parallel (r = 0.79, p < 0.001) and perpendicular (r = 0.63, p < 0.001) to the surface of the skin, indicating concordance in spatial structure between the two data sets. Needle rotation caused tissue displacement in the area surrounding the needle that was mapped spatially with ultrasound elastography and corresponded to collagen bundles winding around the needle on histological sections. In semi-variograms computed for each ultrasound frame, there was a greater change in the area under the semi-variogram curve across successive frames during needle rotation compared with no rotation. The direction of this change was heterogeneous across subjects. The frame-to-frame variability was 10-fold (p < 0.001) greater with rotation than with no rotation indicating changes in tissue structure during rotation. CONCLUSION: The combination of ultrasound and semi-variogram analyses allows quantitative assessment of dynamic changes in the structure of human connective tissue in vivo.