Value of tissue harmonic imaging (THI) and contrast harmonic imaging (CHI) in detection and characterisation of breast tumours

The purpose of this study was to investigate the extent to which tissue harmonic imaging (THI), speckle reduction imaging (SRI), spatial compounding (SC) and contrast can improve detection and differentiation of breast tumours. We examined 38 patients (14 benign, 24 malignant tumours) with different combinations of THI, SRI and SC. The effect on delineation, margin, tissue differentiation and posttumoral phenomena was evaluated with a three-point score. Additionally, 1oo not palpable tumours (diameters: 4–15 mm) were examined by contrast harmonic imaging (CHI) with power Doppler. After bolus injection (0.5 ml Optison), vascularisation and enhancement were observed for 20 min. The best combination for detection of margin, infiltration, echo pattern and posterior lesion boundary was the combination of SRI level 2 with SC low. THI was helpful for lesions OF more than 1 cm depth. In native Power Doppler, vessels were found in 54 of 100 lesions. Within 5 min after contrast medium (CM) injection, marginal and penetrating vessels increased in benign and malignant tumours and central vessels mostly in carcinomas (p<0.05). A diffuse CM accumulation was observed up to 20 min after injection in malignant tumours only (p<0.05). THI, SRI and SC improved delineation and tissue differentiation. Second-generation contrast agent allowed detection of tumour vascularisation with prolonged enhancement

Geological, Physical and Chemical Foundations

Modern tidal flats are coastal geomorphological features with a recentgeologic history (Holocene period, 10,000 YBP) that are found globally, underdifferent climatic, hydrodynamic and sedimentological regimes. They are primarilycharacterized by fine-grained sedimentary deposits (silt and clay) that present uniquephysical and chemical properties, in comparison to other sediment types. The input ofsediments to mudflats can be either riverine, from offshore, and/or from the erosion ofcoastal sedimentary deposits. Tides and tidal currents are the dominant hydrodynamicforces shaping mudflats, with wave action playing a secondary role. Theoccurrence of intermittent or temporary flooding and the presence of variable redox(oxidation-reduction) conditions are typical features of mudflat sediments. Thetemporally and spatially variable changes from aerobic, oxidized states of mudflatsediment and porewater to anaerobic, reduced states drive particular redox reactionsthat govern the characteristic chemical processes and biogeochemical functioningthat distinguish mudflats from other coastal settings. Mudflat sediments are not inert;the high surface area:volume ratio of fine-grained sediment particles offers a vast andstructurally-complex landscape for colonization by microbes that rely on surfaceadhesionprocesses. Photosynthetic microalgae belonging to several taxonomicgroups (collectively known as microphytobenthos MPB) are the dominant microorganismsgrowing in association with sedimentary particles, and forming a biofilmlayer on top. In addition to physical forces, living benthic communities modifysediment properties as part of their normal physiology (micro- and macro-biota)and feeding, movement, and burrowing activity (meio- and macrofauna), especiallyin relation to stabilization and destabilization processes. These may ultimately havemarked effects on sediment stability and geomorphology. The interplay between suchbiological processes and sediments in mudflats is currently an active field of research.Fil: Pan, Jeronimo. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Geología de Costas y del Cuaternario. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto de Geología de Costas y del Cuaternario; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Pratolongo, Paula Daniela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; ArgentinaFil: Cuadrado, Diana Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentin