scholarly journals Interior region-of-interest reconstruction using a small, nearly piecewise constant subregion

2011 ◽  
Vol 38 (3) ◽  
pp. 1307-1312 ◽  
Author(s):  
Katsuyuki Taguchi ◽  
Jingyan Xu ◽  
Somesh Srivastava ◽  
Benjamin M. W. Tsui ◽  
Jochen Cammin ◽  
...  
Keyword(s):  
Region Of Interest ◽  
Interior Region ◽  
Piecewise Constant

scholarly journals A General Total Variation Minimization Theorem for Compressed Sensing Based Interior Tomography

2009 ◽  
Vol 2009 ◽  
pp. 1-3 ◽  
Author(s):  
Weimin Han ◽  
Hengyong Yu ◽  
Ge Wang
Keyword(s):  
Compressed Sensing ◽  
Total Variation ◽  
General Theorem ◽  
Region Of Interest ◽  
Delta Function ◽  
Piecewise Constant Function ◽  
Mathematical Tool ◽  
Total Variation Minimization ◽  
Piecewise Constant ◽  
Dirac Delta

Recently, in the compressed sensing framework we found that a two-dimensional interior region-of-interest (ROI) can be exactly reconstructed via the total variation minimization if the ROI is piecewise constant (Yu and Wang, 2009). Here we present a general theorem charactering a minimization property for a piecewise constant function defined on a domain in any dimension. Our major mathematical tool to prove this result is functional analysis without involving the Dirac delta function, which was heuristically used by Yu and Wang (2009).

Semi-permeable Filters for Interior Region of Interest Dose Reduction in X-ray Microscopy

2021 ◽  
pp. 61-66
Author(s):  
Yixing Huang ◽  
Leonid Mill ◽  
Robert Stoll ◽  
Lasse Kling ◽  
Oliver Aust ◽  
...  
Keyword(s):  
Dose Reduction ◽  
Region Of Interest ◽  
Interior Region ◽  
X Ray

scholarly journals Multi Source Translation Based Projection Completion for Interior Region of Interest Tomography with CBCT

2022 ◽  
Author(s):  
Tan Chuandong ◽  
Haijun Yu ◽  
yarui xi ◽  
Li Lei ◽  
mingjuan liao ◽  
...  
Keyword(s):  
Region Of Interest ◽  
Interior Region

scholarly journals Exact Interior Reconstruction from Truncated Limited-Angle Projection Data

2008 ◽  
Vol 2008 ◽  
pp. 1-6 ◽  
Author(s):  
Yangbo Ye ◽  
Hengyong Yu ◽  
Ge Wang
Keyword(s):  
Analytic Continuation ◽  
Prior Knowledge ◽  
Classical Theory ◽  
Region Of Interest ◽  
Projection Data ◽  
Filtered Backprojection ◽  
Interior Region ◽  
Volume Of Interest ◽  
Interior Volume ◽  
Limited Angle

Using filtered backprojection (FBP) and an analytic continuation approach, we prove that exact interior reconstruction is possible and unique from truncated limited-angle projection data, if we assume a prior knowledge on a subregion or subvolume within an object to be reconstructed. Our results show that (i) the interior region-of-interest (ROI) problem and interior volume-of-interest (VOI) problem can be exactly reconstructed from a limited-angle scan of the ROI/VOI and a 180 degree PI-scan of the subregion or subvolume and (ii) the whole object function can be exactly reconstructed from nontruncated projections from a limited-angle scan. These results improve the classical theory of Hamaker et al. (1980).

scholarly journals Piecewise-Constant-Model-Based Interior Tomography Applied to Dentin Tubules

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Peng He ◽  
Biao Wei ◽  
Steve Wang ◽  
Stuart R. Stock ◽  
Hengyong Yu ◽  
...  
Keyword(s):  
Volume Rendering ◽  
Region Of Interest ◽  
Field Of View ◽  
Reconstruction Method ◽  
Angular Range ◽  
Filtered Backprojection ◽  
Truncated Data ◽  
Piecewise Constant ◽  
Piecewise Constant Model

Dentin is a hierarchically structured biomineralized composite material, and dentin’s tubules are difficult to study in situ. Nano-CT provides the requisite resolution, but the field of view typically contains only a few tubules. Using a plate-like specimen allows reconstruction of a volume containing specific tubules from a number of truncated projections typically collected over an angular range of about 140°, which is practically accessible. Classical computed tomography (CT) theory cannot exactly reconstruct an object only from truncated projections, needless to say a limited angular range. Recently, interior tomography was developed to reconstruct a region-of-interest (ROI) from truncated data in a theoretically exact fashion via the total variation (TV) minimization under the condition that the ROI is piecewise constant. In this paper, we employ a TV minimization interior tomography algorithm to reconstruct interior microstructures in dentin from truncated projections over a limited angular range. Compared to the filtered backprojection (FBP) reconstruction, our reconstruction method reduces noise and suppresses artifacts. Volume rendering confirms the merits of our method in terms of preserving the interior microstructure of the dentin specimen.

SU-F-J-183: Interior Region-Of-Interest Tomography by Using Inverse Geometry System

2016 ◽  
Vol 43 (6Part11) ◽  
pp. 3450-3450
Author(s):  
K Kim ◽  
D Kim ◽  
S Kang ◽  
T Kim ◽  
D Shin ◽  
...  
Keyword(s):  
Region Of Interest ◽  
Interior Region ◽  
Inverse Geometry

A technique for protecting delicate specimens during processing

1989 ◽  
Vol 47 ◽  
pp. 982-983
Author(s):  
R.J. Mount ◽  
R.V. Harrison
Keyword(s):  
Basilar Membrane ◽  
Low Cost ◽  
Organ Of Corti ◽  
Region Of Interest ◽  
Sensory Epithelium ◽  
Physical Damage ◽  
Air Drying ◽  
Specimen Handling ◽  
Two Component

The sensory end organ of the ear, the organ of Corti, rests on a thin basilar membrane which lies between the bone of the central modiolus and the bony wall of the cochlea. In vivo, the organ of Corti is protected by the bony wall which totally surrounds it. In order to examine the sensory epithelium by scanning electron microscopy it is necessary to dissect away the protective bone and expose the region of interest (Fig. 1). This leaves the fragile organ of Corti susceptible to physical damage during subsequent handling. In our laboratory cochlear specimens, after dissection, are routinely prepared by the O-T- O-T-O technique, critical point dried and then lightly sputter coated with gold. This processing involves considerable specimen handling including several hours on a rotator during which the organ of Corti is at risk of being physically damaged. The following procedure uses low cost, readily available materials to hold the specimen during processing ,preventing physical damage while allowing an unhindered exchange of fluids.Following fixation, the cochlea is dehydrated to 70% ethanol then dissected under ethanol to prevent air drying. The holder is prepared by punching a hole in the flexible snap cap of a Wheaton vial with a paper hole punch. A small amount of two component epoxy putty is well mixed then pushed through the hole in the cap. The putty on the inner cap is formed into a “cup” to hold the specimen (Fig. 2), the putty on the outside is smoothed into a “button” to give good attachment even when the cap is flexed during handling (Fig. 3). The cap is submerged in the 70% ethanol, the bone at the base of the cochlea is seated into the cup and the sides of the cup squeezed with forceps to grip it (Fig.4). Several types of epoxy putty have been tried, most are either soluble in ethanol to some degree or do not set in ethanol. The only putty we find successful is “DUROtm MASTERMENDtm Epoxy Extra Strength Ribbon” (Loctite Corp., Cleveland, Ohio), this is a blue and yellow ribbon which is kneaded to form a green putty, it is available at many hardware stores.

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