scholarly journals Calibrated scintigraphic imaging procedures improve quantitative assessment of the cardiac sympathetic nerve activity

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Koichi Okuda ◽  
Kenichi Nakajima ◽  
Chiemi Kitamura ◽  
Yumiko Kirihara ◽  
Mitsumasa Hashimoto ◽  
...  
Keyword(s):  
Calibration Method ◽  
Imaging Systems ◽  
Imaging Procedures ◽  
Scintigraphic Imaging ◽  
Cardiac Sympathetic Nerve Activity ◽  
Calibration Phantom ◽  
Normal Individuals ◽  
Patients With Heart Failure ◽  
Institutional Differences ◽  
Quantitative Results

AbstractThe 123I-labeled meta-iodobenzylguanidine (MIBG) is an analogue of noradrenaline that can evaluate cardiac sympathetic activity in scintigraphy. Quantitative analysis of 123I-MIBG images has been verified in patients with heart failure and neurodegenerative diseases. However, quantitative results differ due to variations in scintigraphic imaging procedures. Here, we created and assessed the clinical feasibility of a calibration method for 123I-MIBG imaging. The characteristics of scintigraphic imaging systems were determined using an acrylic calibration phantom to generate a multicenter phantom imaging database. Calibration factors corresponding to the scintigraphic imaging procedures were calculated from the database and applied to a clinical study. The results of this study showed that the calibrated analysis eliminated inter-institutional differences among normal individuals. In summary, our standardization methodology for 123I-MIBG scintigraphy could provide the basis for improved diagnostic precision and better outcomes for patients.

Precise calibration method for arbitrary beam trajectories in scanning optical imaging systems

2021 ◽  
Author(s):  
Michał Meina ◽  
Patrycjusz Stremplewski ◽  
Carlos Lopez-Mariscal ◽  
Szymon Tamborski ◽  
Maciej Bartuzel ◽  
...  
Keyword(s):  
Optical Imaging ◽  
Calibration Method ◽  
Imaging Systems

Hybrid calibration method of a wide-view-angle Mueller polarimeter for hyper-numerical-aperture imaging systems

2020 ◽  
Vol 18 (8) ◽  
pp. 081202
Author(s):  
Jianhui Li ◽  
Yanqiu Li ◽  
Ke Liu ◽  
Guodong Zhou ◽  
Lihui Liu ◽  
...  
Keyword(s):  
Numerical Aperture ◽  
Calibration Method ◽  
Imaging Systems

scholarly journals Fluoroscopy-based laser projection system for surgical guidance and its calibration methods

10.29007/m1cq ◽  
2018 ◽  
Author(s):  
Sanghyun Joung ◽  
Hyunwoo Lee ◽  
Chul-Woo Park ◽  
Chnag-Wug Oh ◽  
Il-Hyung Park
Keyword(s):  
Experimental System ◽  
Ccd Camera ◽  
Calibration Method ◽  
Optical Tracking ◽  
Angular Error ◽  
Measurement Unit ◽  
Projection System ◽  
Calibration Phantom ◽  
Calibration Methods ◽  
Laser Module

We have developed a laser projection system, which can project laser on corresponding position to surgical planning drawn at a fluoroscopic image without an optical tracking system. In this paper, we introduce a spatial calibration method between a laser module and a fluoroscope for the laser projection and evaluate its accuracy with a mimic experimental system. The experimental system consists of a laser module, a distance measurement unit and a CCD camera. The laser modules can project arbitrary line on surface by reflecting a point source laser with two galvanometers. We designed a calibration phantom by combining a collimator for accurate laser pattern positioning and stainless steel ball arrays for calculation of an extrinsic parameter of a C-arm fluoroscopy. We set a projection plane having ruler in 400mm distance from the CCD camera, and set 54 points on the screen. The laser module projects points with respect to the set points, and a distance error between set points and projected points and angular error are calculated. The distance errors is 1.5±1.9 mm (average ± standard deviation). Maximum error was 7.5 mm. Angular error was smaller than 2 degrees. The laser projection system and its calibration method shows clinically acceptable accuracy and the clinical application is the next step.

scholarly journals Selenium level in patients with heart failure versus normal individuals

2019 ◽  
Vol 10 (1) ◽  
pp. 210 ◽  
Author(s):  
Rahmatollah Rafiei ◽  
Ahmad Mirdamadi ◽  
Gharae Kahazaipour ◽  
Lotfollah Fouladi
Keyword(s):  
Heart Failure ◽  
Selenium Level ◽  
Normal Individuals ◽  
Patients With Heart Failure

Methods for Post Hoc Quantitative Computed Tomography Bone Density Calibration: Phantom-Only and Regression

2018 ◽  
Vol 140 (9) ◽  
Author(s):  
Jacob M. Reeves ◽  
Nikolas K. Knowles ◽  
George S. Athwal ◽  
James A. Johnson
Keyword(s):  
Computed Tomography ◽  
Quantitative Computed Tomography ◽  
Calibration Method ◽  
Regression Method ◽  
Regression Calibration ◽  
Mineral Density ◽  
Tube Voltage ◽  
Calibration Equation ◽  
Calibration Phantom ◽  
Post Hoc

Quantitative computed tomography (qCT) relies on calibrated bone mineral density data. If a calibration phantom is absent from the CT scan, post hoc calibration becomes necessary. Scanning a calibration phantom after-the-fact and applying that calibration to uncalibrated scans has been used previously. Alternatively, the estimated density is known to vary with CT settings, suggesting that it may be possible to predict the calibration terms using CT settings. This study compares a novel CT setting regression method for post hoc calibration to standard and post hoc phantom-only calibrations. Five cadaveric upper limbs were scanned at 11 combinations of peak tube voltage and current (80–140 kV and 100–300 mA) with two calibration phantoms. Density calibrations were performed for the cadaver scans, and scans of the phantoms alone. Stepwise linear regression determined if the calibration equation terms were predictable using peak tube voltage and current. Peak tube voltage, but not current, was significantly correlated with regression calibration terms. Calibration equation slope was significantly related to the type of phantom (p < 0.001), calibration method (p = 0.026), and peak tube voltage (p < 0.001), but not current (p = 1.000). The calibration equation vertical intercept was significantly related to the type of phantom (p < 0.001), and peak tube voltage (p = 0.006), but not calibration method (p = 0.682), or current (p = 0.822). Accordingly, regression can correlate peak tube voltage with density calibration terms. Suggesting that, while standard qCT calibration is preferable, regression calibration may be an acceptable post hoc method when necessary.

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