Design and optimization of a breast-dedicated SPECT scanner with multi-lofthole collimation

2022 ◽  
Vol 17 (01) ◽  
pp. P01006
Author(s):  
M. Saed ◽  
A. Sadremomtaz ◽  
H. Mahani
Keyword(s):  
Energy Resolution ◽  
High Sensitivity ◽  
Opening Angle ◽  
System Sensitivity ◽  
Design And Optimization ◽  
Step And Shoot ◽  
Spect System ◽  
Septal Penetration ◽  
Higher Sensitivity ◽  
Do So

Abstract Background: the need for simultaneous high-sensitivity and high-resolution breast SPECT imaging mandates to design and optimize dedicated scanners. Therefore, this work aims to design and optimize a novel breast-dedicated SPECT system with multi-lofthole collimator. Materials and Methods: in this research, a novel breast-dedicated scanner is designed and then optimized. The scanner is equipped with a single full-ring multi-lofthole collimation long with modular NaI(Tl) detectors. The step-and-shoot data acquisition was considered with two steps. Then, an analytic optimization was conducted to balance the existing sensitivity-resolution tradeoff. To do so, several scanner geometries were investigated. The optimal configuration maximized the system sensitivity at a given system resolution. Furthermore, the scanner was also modeled within the GATE simulator. Then, detector energy resolution, septal penetration and scattering, and system sensitivity were calculated. Analytic findings were also compared with the simulated ones. Results: the results showed that high sensitivity of about 2 cps/kBq can be obtained for a diameter of lofthole 3.05 mm with a 75° opening angle. Results of GATE simulations showed clinically acceptable performance of the system offering 9% energy resolution for a point source. The septal penetration and scattering were approximately 0.5% and 0.2%, respectively, for cylindrical water phantom and tungsten as collimator material. Conclusion: the designed SPECT scanner provides promising results in terms of sensitivity and spatial resolution and therefore outperforms the traditional multi-pinhole collimation by a much higher sensitivity at a given system resolution.

scholarly journals Performance of SwiftScan planar and single photon emission computed tomography technology using low-energy high-resolution and sensitivity collimator

2020 ◽  
Author(s):  
Takayuki Shibutani ◽  
Masahisa Onoguchi ◽  
Hiroto Yoneyama ◽  
Takahiro Konishi ◽  
Kenichi Nakajima
Keyword(s):  
High Resolution ◽  
Spatial Resolution ◽  
Single Photon ◽  
Photon Emission ◽  
High Sensitivity ◽  
Low Energy ◽  
Emission Computed Tomography ◽  
System Sensitivity ◽  
Photon Emission Computed Tomography ◽  
Spect System

Abstract Background A new low-energy high-resolution-sensitivity (LEHRS) collimator was developed by General Electric Healthcare. SwiftScan planar and SPECT system using LEHRS collimator were formulated to achieve the low-dose and/or short-term acquisition. We demonstrated the performance of SwiftScan planar and SPECT system with LEHRS collimator using phantoms. Methods Line source, cylindrical and flat plastic dish phantoms were used to evaluate the performance of planar and SPECT images for four patterns of Siemens LEHR, GE LEHR, GE LEHRS and SwiftScan using two SPECT-CT scanners. Each phantom was filled with 99mTc solution, and the spatial resolution, sensitivity and image uniformity were calculated from the planar and SPECT data. Results The full-width at half maximum (FWHM) values as system spatial resolution of Siemens LEHR, GE LEHR and GE LEHRS were 7.3, 7.5 and 7.3 mm, respectively. GE LEHRS showed the lower FWHM value by increasing the blend ratio in Clarity 2D processing. The system sensitivities of Siemens LEHR, GE LEHR and GE LEHRS were 88.4, 67.6 and 89.8 cps/MBq, respectively. The system sensitivity of GE LEHRS increased by approximately 30% compared with that of GE LEHR and was similar to that of Siemens LEHR. The FWHM values of SPECT with an FBP method were 10.3, 10.4, 10.4 and 10.3 mm (p = n.s.). The FWHM values of the OSEM method were better with an increase in iteration values. The differential uniformities of Siemens LEHR, GE LEHR, GE LEHRS and GE SwiftScan were 15.3%, 15.1%, 15.4% and 14.6%, respectively, using the FBP method. The differential uniformity of OSEM method was higher with an increase in iteration value. Conclusion The SwiftScan planar and SPECT have a high sensitivity while maintaining the spatial resolution compared with the conventional system.

scholarly journals Performance analysis of a high-sensitivity multi-pinhole cardiac SPECT system with hemi-ellipsoid detectors

2018 ◽  
Vol 46 (1) ◽  
pp. 116-126 ◽  
Author(s):  
Narayan Bhusal ◽  
Joyoni Dey ◽  
Jingzhu Xu ◽  
Kesava Kalluri ◽  
Arda Konik ◽  
...  
Keyword(s):  
Performance Analysis ◽  
High Sensitivity ◽  
Cardiac Spect ◽  
Spect System

Development Of PVDF Thick Film Interdigitated Capacitors For Pressure Measurement On Flexible Melinex Substrates

2005 ◽  
Vol 870 ◽  
Author(s):  
Arous Arshak ◽  
Khalil Arshak ◽  
Deirdre Morris ◽  
Olga Korostynska ◽  
Essa Jafer
Keyword(s):  
Polymer Film ◽  
Thick Film ◽  
Pressure Measurement ◽  
Pressure Sensors ◽  
High Sensitivity ◽  
Strain Gauges ◽  
Interdigitated Electrodes ◽  
Higher Sensitivity

AbstractIn this work, a PVDF thick film paste was deposited onto interdigitated electrodes to form a capacitor. Two different substrates, alumina and Melinex® were used. Capacitors, fabricated on alumina substrates were tested as strain gauges, and showed a high sensitivity with low hysteresis. Capacitors on Melinex® substrates were tested as pressure sensors by adhering them to planar and cylindrical surfaces and subjecting them to pressures up to 300 kPa. Their sensitivity and hysteresis during cycling were examined and compared. It was found that sensors on cylindrical surfaces showed a higher sensitivity, however the hysteresis was also increased. It is thought that this is due to instabilities in the polymer film, accentuated by stretching of the substrate.

Plastic Optical Fiber Sensor for Detection of Ethanol Concentrations

2020 ◽  
Vol 307 ◽  
pp. 84-89
Author(s):  
Aisyah Hanim Surani ◽  
Affa Rozana Abdul Rashid ◽  
N. Arsad ◽  
Amna Afiqah Nasution Hakim
Keyword(s):  
Optical Fiber ◽  
Evanescent Wave ◽  
Optical Fiber Sensor ◽  
High Sensitivity ◽  
Deionized Water ◽  
Plastic Optical Fiber ◽  
Polymer Optical Fiber ◽  
Ethanol Sensor ◽  
Output Ratio ◽  
Higher Sensitivity

An optimized study of tapered polymer optical fiber (POF) for measurement of different concentration of ethanol in deionized water (0.5%-3.5%) is proposed and demonstrated. This sensor operated based on evanescent wave absorption principle. The cladding of PMMA based POF is removed using organic solvents which can be used to create tapered POF. The unclad length around 1 cm and 3 cm as well as the waist diameters of POF in the range of 5 mm and 8 mm were compared for their efficiency as an ethanol sensor based on power output ratio values. Tapered POF with smaller waist diameter and longer tapered length showed higher sensitivity as ethanol sensor. Therefore, by tailoring the length and tapered diameter of POF, high sensitivity of ethanol sensor can be fabricated.

Design and optimization of a high sensitivity joint torque sensor for robot fingers

Measurement ◽  
2020 ◽  
Vol 152 ◽  
pp. 107328
Author(s):  
Kang Han ◽  
Liheng Chen ◽  
Mingyi Xia ◽  
Qinwen Wu ◽  
Zhenbang Xu ◽  
...  
Keyword(s):  
High Sensitivity ◽  
Joint Torque ◽  
Torque Sensor ◽  
Design And Optimization ◽  
Joint Torque Sensor

Design and Optimization of a Highly Sensitive and Linearity Piezoresistive Pressure Sensor Based on a Combination of Cross Beam-Peninsula-Membrane Structure

2017 ◽  
Author(s):  
Tran Anh Vang ◽  
Xianmin Zhang ◽  
Benliang Zhu
Keyword(s):  
Pressure Sensor ◽  
Pressure Sensors ◽  
Single Crystal Silicon ◽  
High Sensitivity ◽  
Crystal Silicon ◽  
Nonlinearity Error ◽  
Trade Off ◽  
Design And Optimization ◽  
Piezoresistive Pressure Sensor ◽  
Piezoresistive Pressure Sensors

The sensitivity and linearity trade-off problem has become the hotly important issues in designing the piezoresistive pressure sensors. To solve these trade-off problems, this paper presents the design, optimization, fabrication, and experiment of a novel piezoresistive pressure sensor for micro pressure measurement based on a combined cross beam - membrane and peninsula (CBMP) structure diaphragm. Through using finite element method (FEM), the proposed sensor performances as well as comparisons with other sensor structures are simulated and analyzed. Compared with the cross beam-membrane (CBM) structure, the sensitivity of CBMP structure sensor is increased about 38.7 % and nonlinearity error is reduced nearly 8%. In comparison with the peninsula structure, the maximum non-linearity error of CBMP sensor is decreased about 40% and the maximum deflection is extremely reduced 73%. Besides, the proposed sensor fabrication is performed on the n-type single crystal silicon wafer. The experimental results of the fabricated sensor with CBMP membrane has a high sensitivity of 23.4 mV/kPa and a low non-linearity of −0.53% FSS in the pressure range 0–10 kPa at the room temperature. According to the excellent performance, the sensor can be applied to measure micro-pressure lower than 10 kPa.

SU-FF-I-49: The Effects of Magnetic Field On Energy Resolution and Linearity in SPECT System

2005 ◽  
Vol 32 (6Part3) ◽  
pp. 1915-1915
Author(s):  
S Rasaneh ◽  
H Rajabi ◽  
M Farsinejad
Keyword(s):  
Magnetic Field ◽  
Energy Resolution ◽  
Spect System

Synthesis and Detection Experiments of a Biomolecule Detection Probe Based on Fluorescence Changes

2014 ◽  
Vol 998-999 ◽  
pp. 336-339
Author(s):  
Jun Wang ◽  
Da Hai Ren
Keyword(s):  
Energy Transfer ◽  
Fluorescence Intensity ◽  
Fluorescence Probe ◽  
Resonance Energy Transfer ◽  
Resonance Energy ◽  
High Sensitivity ◽  
Fluorescence Probes ◽  
Biomolecule Detection ◽  
Detection Probe ◽  
Higher Sensitivity

The sensitivity of fluorescence probes built upon the resonance energy transfer is not high enough at present. We built a fluorescence probe with high sensitivity (SA-488-sub-nanogold) by means of the fluorochrome Alexa488 (SA-488) labeled by streptavidin, nanogold, and biotin-subpeptide. When the fluorescence molecule SA-488 binds with the nanogold by biotin-subpeptide, the fluorescence intensity will be suppressed because of resonance energy transfer. If there are molecules under test, the energy transfer will be blocked, by which we can get the molecule content from the fluorescence intensity. Using this probe, we acquired a lower detection limit and a higher sensitivity for biotin detection.

scholarly journals A comparison of the 33-item Hypomania Checklist with the 33-item Hypomania Checklist-external assessment for the detection of bipolar disorder in adolescents

2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Xu Chen ◽  
Wei Bai ◽  
Na Zhao ◽  
Sha Sha ◽  
Teris Cheung ◽  
...  
Keyword(s):  
Bipolar Disorder ◽  
Predictive Value ◽  
Area Under The Curve ◽  
High Sensitivity ◽  
Adverse Outcomes ◽  
Clinical Settings ◽  
External Assessment ◽  
Appropriate Treatment ◽  
Youden’S Index ◽  
Higher Sensitivity

Abstract Background Adolescents with bipolar disorder (BD) are often misdiagnosed as having major depressive disorder (MDD), which delays appropriate treatment and leads to adverse outcomes. The aim of this study was to compare the performance of the 33-item Hypomania Checklist (HCL-33) with the 33-item Hypomania Checklist- external assessment (HCL-33-EA) in adolescents with BD or MDD. Methods 147 adolescents with BD and 113 adolescents with MDD were consecutively recruited. The HCL-33 and HCL-33-EA were completed by patients and their carers, respectively. The sensitivity, positive predictive value (PPV), specificity, negative predictive value (NPV), and area under the curve (AUC) were calculated and compared between the two instruments, using cut-off values based on the Youden’s index. Results The total scores of the HCL-33 and HCL-33-EA were positively and significantly correlated (rs = 0.309, P < 0.001). Compared to the HCL-33, the HCL-33-EA had higher sensitivity and NPV (HCL-33: sensitivity = 0.58, NPV = 0.53; HCL-33-EA: sensitivity = 0.81, NPV = 0.60), while the HCL-33 had higher specificity and PPV (HCL-33: specificity = 0.61, PPV = 0.66; HCL-33-EA: specificity = 0.37, PPV = 0.63). Conclusion Both the HCL-33 and HCL-33-EA seem to be useful for screening depressed adolescents for BD. The HCL-33-EA would be more appropriate for distinguishing BD from MDD in adolescents due to its high sensitivity in Chinese clinical settings.

Sign in / Sign up

Export Citation Format

Share Document