The usefulness of SwiftScan technology for bone scintigraphy using a novel anthropomorphic phantom

AbstractThe aim of this study was to demonstrate the usefulness of SwiftScan with a low-energy high-resolution and sensitivity (LEHRS) collimator for bone scintigraphy using a novel bone phantom simulating the human body. SwiftScan planar image of lateral view was acquired in clinical condition; thereafter, each planar image of different blend ratio (0–80%) of Crality 2D processing were created. SwiftScan planar images with reduced acquisition time by 25–75% were created by Poisson’s resampling processing. SwiftScan single photon emission computed tomography (SPECT) was acquired with step-and-shoot and continuous mode, and SPECT images were reconstructed using a three-dimensional ordered subset expectation maximization incorporating attenuation, scatter and spatial resolution corrections. SwiftScan planar image showed a high contrast to noise ratio (CNR) and low percent of the coefficient of variance (%CV) compared with conventional planar image. The CNR of the tumor parts in SwiftScan SPECT was higher than that of the conventional SPECT image of step and shoot acquisition, while the %CV showed the lowest value in all systems. In conclusion, SwiftScan planar and SPECT images were able to reduce the image noise compared with planar and SPECT image with a low-energy high-resolution collimator, so that SwiftScan planar and SPECT images could be obtained a high CNR. Furthermore, the SwiftScan planar image was able to reduce the acquisition time by 25% when the blend ratio of Clarity 2D processing set to more than 40%.

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dSPIC: a deep SPECT image classification network for automated multi-disease, multi-lesion diagnosis

BMC Medical Imaging ◽

10.1186/s12880-021-00653-w ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Qiang Lin ◽

Chuangui Cao ◽

Tongtong Li ◽

Zhengxing Man ◽

Yongchun Cao ◽

...

Keyword(s):

Image Classification ◽

Bone Scintigraphy ◽

Data Augmentation ◽

Spect Imaging ◽

Whole Body ◽

Geometric Transformation ◽

Imaging Data ◽

Generative Adversarial Network ◽

Spect Image ◽

Spect Images

Abstract Background Functional imaging especially the SPECT bone scintigraphy has been accepted as the effective clinical tool for diagnosis, treatment, evaluation, and prevention of various diseases including metastasis. However, SPECT imaging is brightly characterized by poor resolution, low signal-to-noise ratio, as well as the high sensitivity and low specificity because of the visually similar characteristics of lesions between diseases on imaging findings. Methods Focusing on the automated diagnosis of diseases with whole-body SPECT scintigraphic images, in this work, a self-defined convolutional neural network is developed to survey the presence or absence of diseases of concern. The data preprocessing mainly including data augmentation is first conducted to cope with the problem of limited samples of SPECT images by applying the geometric transformation operations and generative adversarial network techniques on the original SPECT imaging data. An end-to-end deep SPECT image classification network named dSPIC is developed to extract the optimal features from images and then to classify these images into classes, including metastasis, arthritis, and normal, where there may be multiple diseases existing in a single image. Results A group of real-world data of whole-body SPECT images is used to evaluate the self-defined network, obtaining a best (worst) value of 0.7747 (0.6910), 0.7883 (0.7407), 0.7863 (0.6956), 0.8820 (0.8273) and 0.7860 (0.7230) for accuracy, precision, sensitivity, specificity, and F-1 score, respectively, on the testing samples from the original and augmented datasets. Conclusions The prominent classification performance in contrast to other related deep classifiers including the classical AlexNet network demonstrates that the built deep network dSPIC is workable and promising for the multi-disease, multi-lesion classification task of whole-body SPECT bone scintigraphy images.

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

10.21203/rs.3.rs-23631/v1 ◽

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.

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Performance Evaluation of a Novel Type of Low-Energy Electron Microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100180525 ◽

1990 ◽

Vol 48 (1) ◽

pp. 354-355

Author(s):

Bertholdand Senftinger ◽

Helmut Liebl

Keyword(s):

Electron Microscope ◽

High Resolution ◽

Field Strength ◽

Numerical Aperture ◽

Low Energy ◽

Energy Electron ◽

High Resolution Imaging ◽

Lens System ◽

Resolution Imaging ◽

Low Energy Electron

During the last few years the investigation of clean and adsorbate-covered solid surfaces as well as thin-film growth and molecular dynamics have given rise to a constant demand for high-resolution imaging microscopy with reflected and diffracted low energy electrons as well as photo-electrons. A recent successful implementation of a UHV low-energy electron microscope by Bauer and Telieps encouraged us to construct such a low energy electron microscope (LEEM) for high-resolution imaging incorporating several novel design features, which is described more detailed elsewhere.The constraint of high field strength at the surface required to keep the aberrations caused by the accelerating field small and high UV photon intensity to get an improved signal-to-noise ratio for photoemission led to the design of a tetrode emission lens system capable of also focusing the UV light at the surface through an integrated Schwarzschild-type objective. Fig. 1 shows an axial section of the emission lens in the LEEM with sample (28) and part of the sample holder (29). The integrated mirror objective (50a, 50b) is used for visual in situ microscopic observation of the sample as well as for UV illumination. The electron optical components and the sample with accelerating field followed by an einzel lens form a tetrode system. In order to keep the field strength high, the sample is separated from the first element of the einzel lens by only 1.6 mm. With a numerical aperture of 0.5 for the Schwarzschild objective the orifice in the first element of the einzel lens has to be about 3.0 mm in diameter. Considering the much smaller distance to the sample one can expect intense distortions of the accelerating field in front of the sample. Because the achievable lateral resolution depends mainly on the quality of the first imaging step, careful investigation of the aberrations caused by the emission lens system had to be done in order to avoid sacrificing high lateral resolution for larger numerical aperture.

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Optimization of spectral-domain optical coherence tomography with a supercontinuum source for in vivo motion detection of low reflective outer hair cells in guinea pig cochleae

Optical Review ◽

10.1007/s10043-021-00654-8 ◽

2021 ◽

Author(s):

Fumiaki Nin ◽

Samuel Choi ◽

Takeru Ota ◽

Zhang Qi ◽

Hiroshi Hibino

Keyword(s):

Optical Coherence Tomography ◽

High Resolution ◽

Guinea Pig ◽

Hair Cells ◽

Sensory Epithelium ◽

Outer Hair Cells ◽

Acquisition Time ◽

Total Acquisition Time ◽

Sd Oct

AbstractSound evokes sub-nanoscale vibration within the sensory epithelium. The epithelium contains not only immotile cells but also contractile outer hair cells (OHCs) that actively shrink and elongate synchronously with the sound. However, the in vivo motion of OHCs has remained undetermined. The aim of this work is to perform high-resolution and -accuracy vibrometry in live guinea pigs with an SC-introduced spectral-domain optical coherence tomography system (SD-OCT). In this study, to reveal the effective contribution of SC source in the recording of the low reflective materials with the short total acquisition time, we compare the performances of the SC-introduced SD-OCT (SCSD-OCT) to that of the conventional SD-OCT. As inanimate comparison objects, we record a mirror, a piezo actuator, and glass windows. For the measurements in biological materials, we use in/ex vivo guinea pig cochleae. Our study achieved the optimization of a SD-OCT system for high-resolution in vivo vibrometry in the cochlear sensory epithelium, termed the organ of Corti, in mammalian cochlea. By introducing a supercontinuum (SC) light source and reducing the total acquisition time, we improve the axial resolution and overcome the difficulty in recording the low reflective material in the presence of biological noise. The high power of the SC source enables the system to achieve a spatial resolution of 1.72 ± 0.00 μm on a mirror and reducing the total acquisition time contributes to the high spatial accuracy of sub-nanoscale vibrometry. Our findings reveal the vibrations at the apical/basal region of OHCs and the extracellular matrix, basilar membrane.

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The Role of Bone Scintigraphy with SPECT/CT in the Characterization and Early Diagnosis of Stage 0 Charcot Neuroarthropathy

Journal of Clinical Medicine ◽

10.3390/jcm9124123 ◽

2020 ◽

Vol 9 (12) ◽

pp. 4123

Author(s):

Raju Ahluwalia ◽

Ahmad Bilal ◽

Nina Petrova ◽

Krishna Boddhu ◽

Chris Manu ◽

...

Keyword(s):

Computed Tomography ◽

Early Diagnosis ◽

Bone Scintigraphy ◽

Photon Emission ◽

Emission Computed Tomography ◽

Charcot Foot ◽

Bone Pathology ◽

Charcot Neuroarthropathy ◽

Focal Uptake ◽

Stage 1

We describe the use of Single Photon Emission Computed Tomography/Computed Tomography (SPECT/CT) in the investigation and diagnosis of Charcot neuroarthropathy (CN) in patients with a hot swollen foot but normal radiographs and clinical suspicion of CN, usually termed Stage 0. This was a retrospective cohort review of 46 diabetes patients who underwent 3 phase bone scintigraphy with “High Resolution” SPECT/CT. The imaging demonstrated that Stage 0 Charcot foot has a distinct bone pathology, which can be classified into three groups: (1) fractures on Computed Tomography (CT) with accompanying focal uptake of tracer on SPECT, (2) bony abnormalities apart from fracture on CT with focal uptake of tracer on SPECT, and (3) normal CT but focal bony uptake of tracer on SPECT. The CT component of SPECT/CT detected bony fractures in 59% of patients. Early treatment with below knee cast and follow-up for 24 months showed only 4 patients who developed Stage 1 Eichenholtz Charcot foot. Our findings support the use of 3 phase bone scintigraphy with SPECT/CT in the characterization and early diagnosis of CN. Stage 0 Charcot foot has a distinct bone pathology which requires urgent treatment to prevent progression to Stage 1 Eichenholtz Charcot foot. If SPECT/CT is unavailable, CT alone will detect bone fracture in 59% patients.

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High resolution neutron scattering study of low-energy magnetic excitations in Nd2-xCexCuO4

Annalen der Physik ◽

10.1002/andp.2065080208 ◽

2010 ◽

Vol 508 (2) ◽

pp. 197-202

Author(s):

M. Loewenhaupt ◽

A. Metz ◽

N. M. Pyka ◽

D. McK. Paul ◽

J. Martin ◽

...

Keyword(s):

High Resolution ◽

Neutron Scattering ◽

Low Energy ◽

Magnetic Excitations ◽

Scattering Study ◽

Neutron Scattering Study

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Interaction Between Basal Stacking Faults and Prismatic Inversion Domain Boundaries in GaN

MRS Proceedings ◽

10.1557/proc-639-g3.44 ◽

2000 ◽

Vol 639 ◽

Cited By ~ 1

Author(s):

Philomela Komninou ◽

Joseph Kioseoglou ◽

Eirini Sarigiannidou ◽

George P. Dimitrakopulos ◽

Thomas Kehagias ◽

...

Keyword(s):

Electron Microscopy ◽

High Resolution ◽

Stacking Faults ◽

High Resolution Electron Microscopy ◽

High Energy ◽

Low Energy ◽

Inversion Domain ◽

Resolution Electron ◽

Domain Boundaries ◽

Inversion Domain Boundaries

ABSTRACTThe interaction of growth intrinsic stacking faults with inversion domain boundaries in GaN epitaxial layers is studied by high resolution electron microscopy. It is observed that stacking faults may mediate a structural transformation of inversion domain boundaries, from the low energy types, known as IDB boundaries, to the high energy ones, known as Holt-type boundaries. Such interactions may be attributed to the different growth rates of adjacent domains of inverse polarity.

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