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Segmentation and Size Measurement of Polyps in CT Colonography [chapter]

J. J. Dijkers, C. van Wijk, F. M. Vos, J. Florie, Y. C. Nio, H. W. Venema, R. Truyen, L. J. van Vliet
2005 Lecture Notes in Computer Science  
We evaluate our method by comparing the automated size measurement with those of two radiologists using scans of a colon phantom.  ...  We present an automatic method for measuring the polyp size. The method is based on a robust segmentation method that grows a surface patch over the entire polyp surface starting from a seed.  ...  The size measurements for polyps are based upon the segmented patches. The edges of these patches are projected along the polyp axis onto a plane.  ... 
doi:10.1007/11566465_88 fatcat:he3yatp7obbbhg73zlkxah7yvy

Size Measurement of Nanoparticle Assembly Using Multilevel Segmented TEM Images

Paisarn Muneesawang, Chitnarong Sirisathitkul
2015 Journal of Nanomaterials  
Multilevel image segmentation is demonstrated as a rapid and accurate method of quantitative analysis for nanoparticle assembly in TEM images.  ...  Furthermore, the method exhibits scale invariance based on comparable results from images of different magnifications.  ...  Thomas Randall Lee for their contributions and suggestions regarding the synthesis of nanoparticles. TEM images were taken with the assistance of Pikul Ratphonsan at the Khon Kaen University.  ... 
doi:10.1155/2015/790508 fatcat:d2fizzrbjbf35pid5h4pezcssq

Segmentation based on measures of contrast, homogeneity, and region size

Sankar K. Pal, Nikhil R. Pal
1987 IEEE Transactions on Systems, Man and Cybernetics  
Abstract -Two algorithms are described for automatic image segmenta tion using a "homogeneity" measure and "Contrast" measure defined on the cooccurrence matrix of the image.  ...  The measure of contrast involves the concept of logarithmic response (adaptibility with background inten sity) of the human visual system.  ...  The following algorithm introduces the concept of size of regions into the composite measure g K K1 (12) and thereby attempts to eliminate the need of a separate merging phase.Letus define where A R size  ... 
doi:10.1109/tsmc.1987.6499294 fatcat:q3dmvnhgrvakzlnyqqbe6r2bhu

Effect of micro-computed tomography voxel size and segmentation method on trabecular bone microstructure measures in mice

Blaine A. Christiansen
2016 Bone Reports  
The Qualitatively Selected segmentation method more consistently estimated trabecular bone volume fraction (BV/TV) and trabecular thickness across different voxel sizes, but the Histogram segmentation  ...  Additionally, the two segmentation methods provided similar trabecular bone outcomes for scans with small nominal voxel sizes, but considerably different outcomes for scans with larger voxel sizes.  ...  The content is solely the responsibility of the author and does not necessarily represent the official views of the National Institutes of Health.  ... 
doi:10.1016/j.bonr.2016.05.006 pmid:27430011 pmcid:PMC4926804 fatcat:wdk5qeqrhjc3nkfwykc7rs6siy

An industrial 3D vision system for size measurement of iron ore green pellets using morphological image segmentation

Matthew J. Thurley, Tobias Andersson
2008 Minerals Engineering  
Literature review highlights that in the area of size measurement of pellets and rocks, no other researchers make this distinction between entirely and partially visible particles.  ...  Sizing is performed based on best-fit-rectangle, classified into size classes based on one quarter of the measured sieving samples, and then compared against the remaining sieve samples.  ...  Swedish research funding body VIN-NOVA, our industry partners, LKAB, Boliden Mining, and SSAB Steel, and to the staff at ProcessIT Innovations for all their efforts in arranging and facilitating the 3D measurement  ... 
doi:10.1016/j.mineng.2007.10.020 fatcat:xiu3fzchjzaipccuwfgnnvzktm

Accuracy of in vitro mandibular volumetric measurements from CBCT of different voxel sizes with different segmentation threshold settings

Ting Dong, Lunguo Xia, Chenglin Cai, Lingjun Yuan, Niansong Ye, Bing Fang
2019 BMC Oral Health  
To determine the accuracy of volumetric measurements of the mandible in vitro by cone-beam computed tomography (CBCT) and to analyze the influence of voxel sizes and segmentation threshold settings on  ...  The second aim was to evaluate the effects of voxel sizes and HU thresholds on volumetric measurements and to assess optimal segment thresholds for different voxel sizes of CBCT volumetric measurement.  ...  The measurements of CBCTscan volumes deviated from those of laser-scan volumes by + 7.67% to − 3.05%, with different HU thresholds of segmentation and voxel sizes ( Table 2 ).  ... 
doi:10.1186/s12903-019-0891-5 pmid:31484529 pmcid:PMC6727515 fatcat:boubncdtzngrbddybm6usbrfdq

Effects of slice thickness and head rotation when measuring glioma sizes on MRI: in support of volume segmentation versus two largest diameters methods

Pierre Schmitt, Emmanuel Mandonnet, Adrien Perdreau, Elsa D. Angelini
2013 Journal of Neuro-Oncology  
A database of lesions of various shapes and sizes, segmented on 3D-SPGR MRI images, was acquired on 65 patients with low-grade glioma.  ...  This paper presents a study of the effects of scanning parameters variability when assessing glioma sizes on MRI.  ...  We therefore studied size measurements on both segmented lesions and residues as a group of 121 segmented tumors encoded on binary masks with values 0 and 1.  ... 
doi:10.1007/s11060-013-1051-4 pmid:23397270 fatcat:pivjizg2tza3hlv263s3swztym

A Comparative Study of Reproducibility, Reliability and Accuracy in Measuring Mesiodistal Tooth Size Using Four Different Methods — 2D Digital, 3D CBCT, 3D Segmented and 3D Intraoral Scanner Method [chapter]

Vanessa Paredes, Beatriz Tarazona, Natalia Zamora, Yanira Hernandez, Verónica San José
2015 Issues in Contemporary Orthodontics  
After obtaining the four types of models, we proceeded to study the measurement of tooth sizes (Figure 14) . Segmented and 3D CBCT method.  ...  Figure 16 . 16 Scatterplot of points at which measurements of tooth sizes 2D digital Method for 2D versus 3D CBCT segmented Method are compared.  ... 
doi:10.5772/59366 fatcat:meqb7y2xkvfurdtxr4b6vubqzy

PROGNOSTIC VALUE OF MICROVASCULAR OBSTRUCTION AND INFARCT SIZE MEASURED BY CARDIAC MAGNETIC RESONANCE IN PATIENTS WITH ST-SEGMENT ELEVATION MYOCARDIAL INFARCTION: A META-ANALYSIS OF INDIVIDUAL PATIENT DATA

Matthijs van Kranenburg, Michael Magro, Suzanne de Waha, Holger Thiele, Vicente Bodi Peris, Alexandre Cochet, Gert Klug, Edwin Wu, Dan Atar, Peter Bernhardt, Ronak Delewi, Eric Boersma (+2 others)
2013 Journal of the American College of Cardiology  
0.012), prior myocardial infarction (Exp(B) = 2.048, P = 0.012), prior PCI (Exp(B) = 2.243, P = 0.003), TIMI-flow (0, 1 and 2, Exp(B) = 1.869, P = 0.017), MVO-LGE (Exp(B) = 3.654, P = 0.001), infarct size  ...  methods: A multicenter, multivendor meta-analysis of individual patient data was set up. Data from 9 centers (8 studies) from 7 countries were pooled.  ... 
doi:10.1016/s0735-1097(13)60807-4 fatcat:obzzfo5g35bathcvhuevyoidpu

PROGNOSTIC SIGNIFICANCE OF MICROVASCULAR OBSTRUCTION AND INFARCT SIZE MEASURED BY CARDIOVASCULAR MAGNETIC RESONANCE FOR THE ASSESSMENT OF LEFT VENTRICULAR REMODELING IN PATIENTS WITH ST-SEGMENT ELEVATION MYOCARDIAL INFARCTION: INSIGHT FROM A POOLED ANALYSIS OF INDIVIDUAL PATIENT DATA

Matthijs van Kranenburg, Tuncay Yetgin, Olivier Manintveld, Dan Atar, Peter Buser, Edwin Wu, Daniel Lee, Vicente Bodi Peris, Peter Bernhardt, Wolfgang Rottbauer, Ronak Delewi, Eric Boersma (+3 others)
2014 Journal of the American College of Cardiology  
The aim of this study was to determine whether microvascular obstruction and infarct size (IS%LV), assessed by contrast-enhanced cardiovascular magnetic resonance (CE-CMR) early after STEMI, were predictive  ...  Left ventricular (LV) remodeling is a precursor of the development of heart failure and is an important predictor of mortality after STelevation myocardial infarction (STEMI).  ...  The aim of this study was to determine whether microvascular obstruction and infarct size (IS%LV), assessed by contrast-enhanced cardiovascular magnetic resonance (CE-CMR) early after STEMI, were predictive  ... 
doi:10.1016/s0735-1097(14)61141-4 fatcat:quokyhybmjfhxkhkse2cza6hyi

The Effects of Integration Time and Size-of-Source on the Temperature Measurement of Segmented Chip Formation Using Infrared Thermography

Jarred C. Heigel, Eric P. Whitenton
2009 ASME 2009 International Manufacturing Science and Engineering Conference, Volume 2   unpublished
This paper illustrates the errors due to integration time and size-of-source effects when measuring the temperature of segmented chip formation using infrared (IR) thermography.  ...  In this study, an ideal infrared camera is simulated to understand the effects of integration time and size-of-source on the measurement.  ...  ACKNOWLEDGMENTS The authors would like to thank Robert Ivester, Johannes Soons, and Alkan Donmez of NIST for their support.  ... 
doi:10.1115/msec2009-84319 fatcat:rrggetddvjegrj22fl6vxm3jnm

Evaluation of Segmentation Techniques Using Region Size and Boundary Information [chapter]

D. P. Dogra, A. K. Majumdar, S. Sural
2009 Lecture Notes in Computer Science  
A measure is proposed to evaluate four well referred segmentation algorithms. The metric proposed in this work is composed of both size and boundary of segments.  ...  In computer vision, unsupervised segmentation algorithms, although of great interest, often suffer from lack of a well-defined measure to evaluate.  ...  Thus, a measure that considers both size and boundary of regions can be of great use in defining segmentation accuracy.  ... 
doi:10.1007/978-3-642-11164-8_46 fatcat:lflx2sginvhuxjbwbjavpo27mi

Retinal Structure and Gene Therapy Outcome in Retinoschisin-Deficient Mice Assessed by Spectral-Domain Optical Coherence Tomography

Yong Zeng, Ronald S. Petralia, Camasamudram Vijayasarathy, Zhijian Wu, Suja Hiriyanna, Hongman Song, Ya-Xian Wang, Paul A. Sieving, Ronald A. Bush
2016 Investigative Ophthalmology and Visual Science  
Correlation of width and area measurements of cavity size Cavity segmentation and size measurement using Image J.  ...  ON: optic nerve; IS: inner segment; OS: outer segment. Scale bar: 100 m. Measurements are shown in the figure. The average of these eight measurements was used as the cavity size for each retina.  ... 
doi:10.1167/iovs.15-18920 pmid:27409484 pmcid:PMC4968785 fatcat:zyrfouz4mzeetkwovalvqta7ge

Discrepancy between frequency domain optical coherence tomography and intravascular ultrasound in human coronary arteries and in a phantom in vitro coronary model

In-Cheol Kim, Chang-Wook Nam, Yun-Kyeong Cho, Hyoung-Seob Park, Hyuck-Jun Yoon, Hyungseop Kim, In-Sung Chung, Seongwook Han, Seung-Ho Hur, Yoon-Nyun Kim, Kwon-Bae Kim
2016 International Journal of Cardiology  
FD-OCT measurements were larger, particularly in non-stented than stented segments, and diameter was smaller by QCA vs. IVUS or FD-OCT.  ...  ) and intravascular ultrasound (IVUS) measurements in a phantom coronary model and in human coronary arteries within and outside stented segments.  ...  measurement of definite vessel size [20] .  ... 
doi:10.1016/j.ijcard.2016.07.080 pmid:27434362 fatcat:2ndnynmyxbdkfcljfo64aphrwi

X-Ray Beam Segment Size and Entrance Location Effects on the Integral Quality Monitor (IQM®) Signal and Usefulness in Predicting Complex Segment Output Signals

2020 Journal of Biomedical Physics and Engineering  
The dependence of signals on segment size, shape, location and combination was investigated.  ...  A method of correcting predicted signals in smaller segments needs to be laid down to get a better match with measured signals.  ...  Conflict of Interest None  ... 
doi:10.31661/jbpe.v0i0.1162 pmid:32802788 pmcid:PMC7416101 fatcat:gcgejookgjcxriv2vdrzxnpe6i
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