Volume images

Among 3D tomographic systems the systems, capable to reconstruct the complete volume image of object for one scanning session, are of interest. 

Detailed description of a porous microstructure is an essential prerequisite for unveiling the influence of pore morphology on the underlying two-phase behavior. This can be achieved either by 3-D volume imaging or by constructing a digital microstructure based on stochastic reconstruction models. Non-invasive techniques, such as X-ray micro-tomography, are the popular methods for 3-D... 

Figure 10-10 Volume images of the underground formations in the Minamikayabe area predicted by smooth (top panel) and focusing (bottom panel) inversion.

Figure 10-10 shows the volume images of the models predicted by smooth (top panel) and focusing (bottom panel) inversion. The inversion results are consistent with the 2-D interpretation results of Takasugi et al., (1992), and with 3-D inversion results obtained by QL inversion (Zhdanov et ah, 2000). 

Most types of selective excitation can be modified for simultaneous excitation of n slices or volume elements. Such an approach is advantageous when a limited number of slices or volume elements, but not the entire 3D object, needs to be investigated. By suitable coding of the volume information in n experiments an improvement in signal-to-noise ratio of can be gained [Boll, Miill]. Compared to 3D volume imaging, multislice and multi-volume techniques (cf. Section 9.1) suffer from the lack of achieving well-defined boundaries. 

These include contact force imaging (CFI) mode, in which the tip is scanned across the sample surface at constant force, tapping mode in which the tip oscillates close to the surface enabling either the forces or phase relationships between load and displacement to be used to form the image, and local force spectroscopy or force/volume imaging in which the variation of force with tip/sample separation at a point can be used to study local interachons. 

Ezzeddine, M.A., et al., CT angiography with whole brain perfused blood volume imaging added clinical value in the assessment of acute stroke. Stroke, 2002. 33(4) p. 959-66. 

Gaboriaud, E, Parcha, B. S., Gee, M. L., Holden, J. A., and StrugneU, R. A. 2008. SpatiaUy resolved force spectroscopy of bacterial surfaces using force-volume imaging. Colloids Surfaces B-Biointerfaces 62, 206-213. 

We meet this case in technics. For instance, in an optical microscope, lenses fulfil the direct and inverse Fourier transforms the light is focused by a condenser onto the object, then diffracted, then collected by an objective, and finally the image is taken by a video camera and seen on a screen. The form of the object is seen as an intensity pattern that is a flat distribution of the optical density, because the phases of the waves forming the image are lost. A holographic technique, which always uses an interference of scattered rays with a reference beam having a known phase, allows the restoration of a volume image of the object. 

In conclusion, real-time registration and fusion of pre-procedure CT volume images with intra-procedure US are feasible and accurate in the experimental setting. Further studies are warranted to validate the system under clinical conditions. For simple biopsies, an experienced interventional radiologist will not ask for such a guidance tool and, given the cost and availability, US and CT guidance... 

Fig. 1.2a-c. A multimodality fusion imaging system (Virtual Navigator System, Esaote SpA, Genoa, ltaly)-real-time registration and fusion of pre-procedure CT volume images with intraprocedure US-used for a percutaneous radiofrequency ablation of an hepatocellular carcinoma targeting of the lesion (a), needle placement (b) and evaluation of the ablation zone... 

Vidholm E, Nystrom I (2005) A haptic interaction technique for volume images based on gradient diffusion. In Proc. First Joint Eurohaptics Conference and Symposium on Haptic Interfaces for Virtual Environment and Teleoperator Systems, pp 336-341... 

As mentioned above, the spm is mostly limited to sampling the near-sinface region of a polymer system. A new technique based on tmafm has been developed to enable volume imaging with the spm. This study tracked a series of height and phase images of a styrene-butadiene-styrene (SBS) triblock polymer microdomain as the surface was being removed 7.5 nm at a time with a plasma etcher. These data are illustrated in Figure 10 (65). 

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