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A proton Computed Tomography system for medical applications

JOURNAL OF INSTRUMENTATION 2013年第2期8卷

作者： Sipala, V. Bruzzi, M. Bucciolini, M. Carpinelli, M. Cirrone, G. A. P. Civinini, C. Cuttone, G. Lo Presti, D. Pallotta, S. Pugliatti, C. Randazzo, N. Romano, F. Scaringella, M. Stancampiano, C. Talamonti, C. Tesi, M. Vanzi, E. Zani, M. Univ Sassari I-07100 Sassari Italy INFN Cagliari I-09042 Monserrato CA Italy Univ Florence Dept Energet I-50139 Florence Italy INFN Florence I-50019 Sesto Fiorentino FI Italy Univ Florence Dept Clin Physiopathol I-50134 Florence Italy Azienda Osped Univ Careggi I-50134 Florence Italy Lab Nazl Sud INFN I-95123 Catania Italy Univ Catania Dept Phys I-95123 Catania Italy INFN Catania I-95123 Catania Italy Ctr Studi & Ric I-00184 Rome Italy Museo Stor Fis Enrico Fermi I-00184 Rome Italy

Proton Computed Tomography (pCT) can improve the accuracy of both patient positioning and dose calculation in proton therapy, enabling to accurately reconstruct the electron density distribution of irradiated tissues. A pCT prototype, equipped with a silicon tracker and a YAG:Ce calorimeter, has been manufactured by an Italian collaboration. First tests under proton beam allowed obtaining good quality tomographic images of a non-homogeneous phantom. Manufacturing of a new large area system with real-time data acquisition is under way.

关键词： Instrumentation for hadron therapy computerized Tomography (CT) and Computed Radiography (CR) medical-image reconstruction methods and algorithms, computer-aided so

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A physico-mathematical formulation based on ray equation for reconstructing refraction-based 3-D image of soft tissue

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JOURNAL OF INSTRUMENTATION 2013年第5期8卷

作者： Yuasa, T. Sunaguchi, N. Ichihara, S. Ando, M. Yamagata Univ Yonezawa Yamagata 9928510 Japan KEK Tsukuba Ibaraki 3050801 Japan Nagoya Med Ctr Nagoya Aichi 4600001 Japan Tokyo Univ Sci Noda Chiba 2788510 Japan

Refraction-contrast computed tomography (CT) can image biological soft tissues and soft materials at a high contrast, which cannot be clearly depicted by contemporary CT based on absorption contrast. It reconstructs a distribution of refractive index from projections, whose data each is an angular deviation from incident direction due to refraction by an object, and is acquired by imaging methods using an angular analyzer, e.g., DEI (diffraction enhance imaging), or DFI (dark field imaging). First, a reconstruction algorithm for refraction-contrast CT is derived from the ray equation of a fundamental equation describing refraction phenomena in geometrical optics. Then, in order to demonstrate its efficacy, we performed imaging experiment using DFI-CT imaging system. A reconstructed image of human breast cancer tissue is presented.

关键词： computerized Tomography (CT) and Computed Radiography (CR) medical-image reconstruction methods and algorithms, computer-aided so

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Numerical simulation of the human ear and the dynamic analysis of the middle ear sound transmission

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JOURNAL OF INSTRUMENTATION 2013年第6期8卷

作者： Yao, W. Ma, J. Huang, X. Shanghai Inst Appl Math & Mech Shanghai 200072 Peoples R China Shanghai Univ Dept Civil Engn Shanghai 200072 Peoples R China Fudan Univ Zhongshan Hosp Dept Otolaryngol Shanghai 200032 Peoples R China

Based on the clinical CT of normal right ear, a 3-D ?nite element (FE) model of the human ear consisting of the external ear canal, middle ear(tympanic membrane, ossicular chain, ligaments, tendons), and inner ear (including semicircular canals, vestibular, spiral cochlear) was constructed in this paper. The complicated structures and inner boundary conditions of middle ear were described in this model. Model analysis and acoustic-structure-?uid coupled dynamic frequency response analysis were conducted on the model. The validity of this model was confirmed by comparing the results with published experimental data. The amplitudes and velocities of tympanic membrane and stapes footplate, sound pressure gain across the middle ear, and the cochlear input impedance were derived. Besides, it was concluded that the ear canal can amplify the sound signal in low frequencies. The modes of vibration of middle ear auditory ossicles, oval window and round window have been analysed. This model can well simulate the acoustic behavior with the interaction of external ear, middle ear and inner ear, which can supply more valuable theoretical support for development and improvement of hearing-aid and artificial inner ear.

关键词： medical-image reconstruction methods and algorithms, computer-aided so Simulation methods and programs image reconstruction in medical imaging computerized Tomography (CT) and Computed Radiography (CR)

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Experimental investigation of mouse kidney aging with SR PCI technology

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JOURNAL OF INSTRUMENTATION 2013年第8期8卷

作者： Yifeng, P. Zehua, Z. Guohao, D. Tiqiao, X. Hongjie, X. Peiping, Z. Shanghai Univ Tradit Chinese Med Putuo Hosp Radiol Dept Shanghai 200062 Peoples R China Chinese Acad Sci Shanghai Inst Appl Phys Shanghai 201204 Peoples R China Chinese Acad Sci Inst High Energy Phys Beijing 100049 Peoples R China

Objective. Basing on the coherence character of the Synchrotron radiation (SR), the mouse kidney study is performed using the propagation-based phase-contrast imaging (PCI) technology which as one approach of the phase contrasts imaging (PCI). The aim of this paper was to visualize the kidney at different ages and evaluate the latent value of aging mechanism with SR phase contrast imaging technology. methods. The experiments were performed at the BL13W1 line of the SSRF (the Shanghai synchrotron radiation facility), the samples were soaked in 10% formalin solution, the mouse kidneys at different ages were imaged on the shelf in the propagation-based phase-contrast imaging setup and captured with CCD. The captured images were analyzed and compared. Results. When the distance is 50 cm between the samples and imaging plate, good contrast and high resolution were obtained in the propagation-based phase-contrast imaging (PCI), as such renal capsule revealed well, and the resolution reach to 30 micron;there is significant difference in the shape and vessels structures among the mouse kidneys at different age. Conclusion. The PCI is good for the applying of main light element organization imaging, the difference in shape and vessels structure between the young and old mouse kidney maybe indicated at some extent with the propagation-based phase-contrast imaging technology.

关键词： X-ray monochromators Instrumentation for synchrotron radiation accelerators medical-image reconstruction methods and algorithms, computer-aided so Accelerator Applications

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Imaging characters of the lung cancer phantoms under the simulative clinical condition performed with hard X-ray in-line holography

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JOURNAL OF INSTRUMENTATION 2013年第7期8卷

作者： Zhang, J. Chen, Y. Li, G. Jiang, X. Chinese Acad Sci Inst High Energy Phys Beijing Peoples R China

The simulative lung cancer tissues under the approximate clinical condition were imaged using in-line holography method with 35 keV synchrotron radiation hard X-ray. The millimeter scale simulative cancer phantoms showed adequate contrast to lung tissues in our experiment. It demonstrates that in-line holography method with synchrotron radiation hard X-ray promises to be a potential sensitive method for the early detection of lung cancer. The image contrast, standard deviation (SD) and normalized standard deviation (NSD) of different areas were calculated. It shows that the traditional method of contrast calculation does not always give a convincible result in image judgment;a standard deviation map of image taken with a proper distance of sample to detector (DSD) will correspond well to the projecting image and supply effective assistance in diagnostic judgment.

关键词： X-ray radiography and digital radiography (DR) Inspection with x-rays medical-image reconstruction methods and algorithms, computer-aided so

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MPGD for breast cancer prevention: a high resolution and low dose radiation medical imaging

MPGD for breast cancer prevention: a high resolution and low...

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2nd International Conference on Micro Pattern Gaseous Detectors

作者： Gutierrez, R. M. Cerquera, E. A. Manana, G. Univ Antonio Narino Ctr Invest Ciencias Basicas & Aplicadas Bogota Colombia Univ Antonio Narino Fac Ingn Biomed & Elect Bogota Colombia

Early detection of small calcifications in mammograms is considered the best preventive tool of breast cancer. However, existing digital mammography with relatively low radiation skin exposure has limited accessibility and insufficient spatial resolution for small calcification detection. Micro Pattern Gaseous Detectors (MPGD) and associated technologies, increasingly provide new information useful to generate images of microscopic structures and make more accessible cutting edge technology for medical imaging and many other applications. In this work we foresee and develop an application for the new information provided by a MPGD camera in the form of highly controlled images with high dynamical resolution. We present a new Super Detail image (S-DI) that efficiently profits of this new information provided by the MPGD camera to obtain very high spatial resolution images. Therefore, the method presented in this work shows that the MPGD camera with SD-I, can produce mammograms with the necessary spatial resolution to detect microcalcifications. It would substantially increase efficiency and accessibility of screening mammography to highly improve breast cancer prevention.

关键词： Pattern recognition, cluster finding, calibration and fitting methods Micropattern gaseous detectors (MSGC, GEM, THGEM, RETHGEM, MHSP, MICROPIC, MICROMEGAS, InGrid, etc) medical-image reconstruction methods and algorithms, computer-aided so X-ray mammography and scinto- and MRI-mammography

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Development of a gamma-ray imager using a large area monolithic 4x4 MPPC array for a future PET scanner

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JOURNAL OF INSTRUMENTATION 2012年第1期7卷

作者： Nakamori, T. Kato, T. Kataoka, J. Miura, T. Matsuda, H. Sato, K. Ishikawa, Y. Yamamura, K. Kawabata, N. Ikeda, H. Sato, G. Kamada, K. Waseda Univ Res Inst Sci & Engn Shinjuku Ku Tokyo Japan Hamamatsu Photon KK Div Solid State Hamamatsu Shizuoka Japan ISAS JAXA Chuo Ku Sagamihara Kanagawa Japan Furukawa Co Ltd Mat Res Lab Tsukuba Ibaraki 3050856 Japan

We report the development of a monolithic MPPC array, which consists of 3x3mm(2) elements arranged as a 4x4 array manufactured by Hamamatsu applicable to next generation PET scanners. We show that the MPPC is suitable for time of flight PET applications by simple measurement using coincident back-to-back 511 keV gamma rays. We demonstrated that the MPPC has much better timing resolution of similar to 600 ps than the APD. We coupled the monolithic MPPC array with the Ce:LYso and Pr:LuAG scintillator matrices as gamma-ray detectors. The energy resolutions were evaluated as similar to 14% with 662 keV gamma-rays and the Ce: LYso achieved the best. We also used a resistor network readout circuit with some optimization. The averaged positional resolution is estimated as similar to 0.27 mm in both x and y directions, while the energy resolution of each pixel was 9.9% for 662 keV gamma rays. Finally we applied the GHz class fast sampling waveform acquisition system to improve performance, and demonstrated efficient noise reduction by the clear detection of 22 keV gamma rays.

关键词： Gamma camera, SPECT, PET PET/CT, coronary CT angiography (CTA) medical-image reconstruction methods and algorithms, computer-aided so

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A CT-ultrasound-coregistered augmented reality enhanced image-guided surgery system and its preliminary study on brain-shift estimation

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JOURNAL OF INSTRUMENTATION 2012年第8期7卷

作者： Huang, C. H. Hsieh, C. H. Lee, J. D. Huang, W. C. Lee, S. T. Wu, C. T. Sun, Y. N. Wu, Y. T. Chang Gung Univ Dept Elect Engn Tao Yuan Taiwan Chang Gung Mem Hosp Dept Neurosurg Tao Yuan Taiwan Natl Cheng Kung Univ Dept Comp Sci & Informat Engn Tainan 70101 Taiwan Natl Yang Ming Univ Dept Biomed Imaging & Radiol Sci Taipei 112 Taiwan

With the combined view on the physical space and the medical imaging data, augmented reality (AR) visualization can provide perceptive advantages during image-guided surgery (IGS). However, the imaging data are usually captured before surgery and might be different from the up-to-date one due to natural shift of soft tissues. This study presents an AR-enhanced IGS system which is capable to correct the movement of soft tissues from the pre-operative CT images by using intra-operative ultrasound images. First, with reconstructing 2-D free-hand ultrasound images to 3-D volume data, the system applies a Mutual-Information based registration algorithm to estimate the deformation between pre-operative and intra-operative ultrasound images. The estimated deformation transform describes the movement of soft tissues and is then applied to the pre-operative CT images which provide high-resoultion anatomical information. As a result, the system thus displays the fusion of the corrected CT images or the real-time 2-D ultrasound images with the patient in the physical space through a head mounted display device, providing an immersive augmented-reality environment. For the performance validation of the proposed system, a brain phantom was utilized to simulate brain-shift scenario. Experimental results reveal that when the shift of an artificial tumor is from 5mm similar to 12mm, the correction rates can be improved from 32% similar to 45% to 87% similar to 95% by using the proposed system.

关键词： Multi-modality systems medical-image reconstruction methods and algorithms, computer-aided so Algoritms and software for radiotherapy Pattern recognition, cluster finding, calibration and fitting methods

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A feasibility study of digital tomosynthesis for volumetric dental imaging

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JOURNAL OF INSTRUMENTATION 2012年第3期7卷

作者： Cho, M. K. Kim, H. K. Youn, H. Kim, S. S. Pusan Natl Univ Sch Mech Engn Pusan 609735 South Korea Pusan Natl Univ Ctr Adv Med Engn Res Pusan 609735 South Korea Pusan Natl Univ Dept Orthodont Yangsan Si 626770 Gyeongnam South Korea

We present a volumetric dental tomography method that compensates for insufficient projection views obtained from limited-angle scans. The reconstruction algorithm is based on the backprojection filtering method which employs apodizing filters that reduce out-of-plane blur artifacts and suppress high-frequency noise. In order to accompolish this volumetric imaging two volume-reconstructed datasets are synthesized. These individual datasets provide two different limited-angle scans performed at orthogonal angles. The obtained reconstructed images, using less than 15% of the number of projection views needed for a full skull phantom scan, demonstrate the potential use of the proposed method in dental imaging applications. This method enables a much smaller radiation dose for the patient compared to conventional dental tomography.

关键词： computerized Tomography (CT) and Computed Radiography (CR) medical-image reconstruction methods and algorithms, computer-aided so X-ray radiography and digital radiography (DR)

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MPGD for breast cancer prevention: a high resolution and low dose radiation medical imaging

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JOURNAL OF INSTRUMENTATION 2012年第7期7卷

作者： Gutierrez, R. M. Cerquera, E. A. Manana, G. Univ Antonio Narino Ctr Invest Ciencias Basicas & Aplicadas Bogota Colombia Univ Antonio Narino Fac Ingn Biomed & Elect Bogota Colombia

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