Anal Bioanal Chem DOI10.1007/s00216-011-4913-7 ORIGINAL PAPER Synchrotron radiation phase-contrast X-ray Ct imaging of acupuncture points Dongming Zhang. Xiaohui Yan. Xinyi Zhang Chenglin liu· Ruishan dang· Tiqiao Xia Received: 28 February 2011/Accepted: 14 March 2011 pringer-Verlag 20 Abstract Three-dimensional (3D) topographic structures of Introduction acupuncture points were investigated by using synchrotron radiation in-line X-ray phase contrast computerized tomogra- Acupuncture has been applied all over the world for several phy. Two acupuncture points, named Zhongji(RN3)and thousand years. Nevertheless, the mechanism of acupunc- Zusanli (ST36), were studied. We found an accumulation of ture is still not well known. Even the structure and the microvessels at each acupuncture point region. Images of the osition of these acupuncture points remain uncertain. vestigate the acupuncture by differe methods. Some valuable discoveries have been made. For Keywords Acupuncture point. Synchrotron radiation example, two visible light emission bands on the surface of X-ray Phase contrast. Microvessel acupuncture points were recorded [1]. The gathering of some trace elements(Ca, Fe, Cu, and Zn)in acupuncture Radiation with Guest Editor Cyril Petibois. ques with Sino Published in the special issue Imaging Techni points was found by the X-ray fluorescence technique [2] Other researchers think that acupuncture points could be D. Zhang·X.Yan·X. Zhang() associated with fascial planes of connective tissue between Synchrotron Radiation Research Center, State Key Laboratory of Surface Physics and Department of Physics, muscles B3, 4]. Despite considerable efforts devoted to probing the anatomy of acupuncture points, however, Shanghai 200433 China characterization of structures of acupuncture points is mail:xy.zhang@fudan.edu.cn elusive. In this report, we study the characteristic acupuncture points by using synchrotron X-ray three- Physics Department of Yancheng Teachers'College, dimensional (3D)imaging to find the structural differences between acupuncture points and the surrounding tissues ond Military Medical University, phase shift rather than the absorption as the imaging signal, 00433. China provides the potential for substantially increased contrast when it is used on biological samples [5, 6]. By calculating Tⅹiao the X-ray phase shift and absorption at the atomic level Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, XPCI was estimated to be more sensitive to light elements Chinese Academy of Sciences, than the absorption-contrast X-ray imaging. Furthermore, by using XPCI together with micro-computed tomography (CT), the X-ray phase contrast computerized tomography P Zhu Beijing Synchrotron Radiation Facility, (XPCT)technique was also developed Various XPCT methods Institute of High Energy Physics, Chinese Academy of Sciences, have been developed over the past decades. They can be Beijing 100039, China classified into interferometric methods [7], diffraction-enhanced Published online: 09 April 2011 2 SpringerORIGINAL PAPER Synchrotron radiation phase-contrast X-ray CT imaging of acupuncture points Dongming Zhang & Xiaohui Yan & Xinyi Zhang & Chenglin Liu & Ruishan Dang & Tiqiao Xiao & Peiping Zhu Received: 28 February 2011 /Accepted: 14 March 2011 # Springer-Verlag 2011 Abstract Three-dimensional (3D) topographic structures of acupuncture points were investigated by using synchrotron radiation in-line X-ray phase contrast computerized tomogra￾phy. Two acupuncture points, named Zhongji (RN3) and Zusanli (ST36), were studied. We found an accumulation of microvessels at each acupuncture point region. Images of the tissues surrounding the acupuncture points do not show such kinds of structure. This is the first time that 3D images have revealed the specific structures of acupuncture points. Keywords Acupuncture point . Synchrotron radiation . X-ray . Phase contrast . Microvessel Introduction Acupuncture has been applied all over the world for several thousand years. Nevertheless, the mechanism of acupunc￾ture is still not well known. Even the structure and the composition of these acupuncture points remain uncertain. In recent years, many researchers have tried to probe the basic structure of acupuncture points and to investigate the physiological mechanism of acupuncture by different methods. Some valuable discoveries have been made. For example, two visible light emission bands on the surface of acupuncture points were recorded [1]. The gathering of some trace elements (Ca, Fe, Cu, and Zn) in acupuncture points was found by the X-ray fluorescence technique [2]. Other researchers think that acupuncture points could be associated with fascial planes of connective tissue between muscles [3, 4]. Despite considerable efforts devoted to probing the anatomy of acupuncture points, however, the characterization of structures of acupuncture points is still elusive. In this report, we study the characteristic of acupuncture points by using synchrotron X-ray three￾dimensional (3D) imaging to find the structural differences between acupuncture points and the surrounding tissues. X-ray phase contrast imaging (XPCI), which uses the phase shift rather than the absorption as the imaging signal, provides the potential for substantially increased contrast when it is used on biological samples [5, 6]. By calculating the X-ray phase shift and absorption at the atomic level, XPCI was estimated to be more sensitive to light elements than the absorption-contrast X-ray imaging. Furthermore, by using XPCI together with micro-computed tomography (CT), the X-ray phase contrast computerized tomography (XPCT) technique was also developed. Various XPCT methods have been developed over the past decades. They can be classified into interferometric methods [7], diffraction-enhanced Published in the special issue Imaging Techniques with Synchrotron Radiation with Guest Editor Cyril Petibois. D. Zhang : X. Yan : X. Zhang (*) Synchrotron Radiation Research Center, State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China e-mail: xy-zhang@fudan.edu.cn C. Liu Physics Department of Yancheng Teachers’ College, Yancheng 224002, China R. Dang The Second Military Medical University, Shanghai 200433, China T. Xiao Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China P. Zhu Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100039, China Anal Bioanal Chem DOI 10.1007/s00216-011-4913-7