1.Evidence that we need more radiation for good health
Chinese Journal of Medical Physics 2002;19(4):193-
In 1958 the speaker believed that background radiation might cause a fatal cancer. In 1970 he believed there was no risk from background or from the small doses received from diagnostic uses of X-rays. Since 1990 he has come to believe that for good health most people need more radiation than they receive from nature. The talk will emphasize the results of two large British radiologists who entered the field between 1955 and 1979, when compared to all other male English physicians of the same age. Had a 29% lower cancer death rate, a 36% lower death rate from non-cancer and a 32% lower death rate from all causes. The chances of such a health improvement being accidental is less than one in one thousand. The lower death rate from all causes results in more than a three year increase in longevity-the same increase in longevity that would result ff all cancer were curable. The US Government sponsored nuclear shipyard worker study shows that the 28,000 nuclear shipyard workers with the greatest radiation doses, when compared to 32,500 shipyard workers who had no on-the-job radiation, had significantly less cancer and a 24% lower death rate from all causes. That is, the nuclear workers had nearly a three-year increase in longevity.The chance of that health improvement being accidental is less than one in ten million billion. The talk will describe a double blind study to test the hypothesis that a moderate dose of ionizing radiation stimulates the immune system of senior citizens in the I.S. Gulf States where cancer mortality is 25% greater than in the mountains, which have about 300% more background radiation than the Gulf States. Radiation deficiency may be a health problem in many areas of the world.
2.Infrastructure for image guided surgery
W.Vannier Michael ; W.Haller John ; C.Ryken Timothy
Chinese Journal of Medical Physics 2002;19(4):219-223,234
Image guided surgery (IGS) requires an integrated environment for seamless acquisition, visualization,manipulation, display, registration and storage of complex data sets. The infrastructure to support IGS integrates image acquisition, networks, presurgical planning, surgical navigation, and archival storage elements. This paper describes the principal components of an integrated IGS environment and an implementation in a large academic medical center. The IGS infrastructure is illustrated for practical applications in neurosurgical case examples.
3.Fast Volume Clipping of Medical Images on GPU
Zhiying ZHU ; Xianglei BU ; Xiaoshan LIN ; Yanli XU
Chinese Journal of Medical Physics 2010;27(2):1731-1733,1740
Objective: When the region of interest is somewhere in the middle of the volumetric data, it will be occluded by other regions of the volumetric data and will be hard to see in the reconstruction of volume rendering. In order to provide doctor with comprehensive, visual and accurate diagnostic information, fast volume dipping of medical images on GPU is proposed in the paper. Methods: The rapid volume clipping is achieved by combining the dipping algorithm with the fast volume rendering algorithm based on GPU. The technique is based on fast volume tendering of medical images on GPU. It works as follows: The space information of the section plane is sent to the shader. Then compare the position of the volume data sets with the section plane to decide whether the data is clipped or not. Our algorithm is different from the algorithm that clipping based on depth stencil. We can see the result that reconstructed from the data sets that remained from any position as long as the section plane is defined. Results: According to the shape the users defined, our algorithm can decide which parts of the volume have to be clipped. Because of using the general graphics hardware acecleration, the proposed method achieves interactive display rate. Conclusions: The experiment shows that the algorithm is significantly fast and can meet the requirements of real-time interactive rendering on the premise of ensuring imaging quality and can be used in surgery simulation and so on.
4.Photodynamic Therapy and Sonodynamic Therapy
Weina LI ; Jiqing YANG ; Yuansheng LIU ; Xuemin QU ; Jun WEN ; Min ZHANG
Chinese Journal of Medical Physics 2010;27(2):1781-1784,1792
Objective: This paper summarized the research status and progress of photodynamic therapy (PDT) and sonodynam-ic therapy (SDT), and we hope this can be a useful reference for clinics or research. Methods: In this review we expound their molecular mechanisms in detail and classify the photosensitizer and sonosensitizer, indicate their applications for the cancer treatment and summarize their new treating modes. PDT and SDT have huge potential for cancer treatment. Results: PDT and SDT have achieved a certain results, whereas there are still many problems, such as tissue oxygen content, new photosensitizer and sonosensitizer, drug dosage and mechanisms of SDT. Conclusions: PDT and SDT, which are new methods for treating cancer, have shown a good application prospect. But PDT has not been universal in clinics and SDT is still in the experiment stage.
5.The study of EEG telemetry technology
Song PENG ; Zuxiang FANG ; Cuiwei YANG ; Qiang LUO
Chinese Journal of Medical Physics 2000;17(4):205-208,210
This Paper brings forward a new technology of EEG Telemetry. Using two FDM channels, the signals can be transmitted through public telephone lines: the EEG signals are transmitted by TDM technology in one channel; the parametes are transmitted to the receiver for identification of data or synchronization in the other channel synchronously. This technology can satisfy almost any routine clinic needs, and also the quahty of transmission is nearly perfect: the distortion is little; distinct noise pollution and shift of base-line do not exist, which is valuable in medical application.
6.Changes of macrophages stimulated by ConA after hyperthermia
Hong WANG ; Lin YANG ; Shenqiu LUO ; Xiaodong MA
Chinese Journal of Medical Physics 2001;18(1):42-43,45
Changes of rats peritoneal macrophages after hyperthermia were stimulated by ConA with ACAS 570 Interactive Laser Cytometer. The results show that the influx of Ca2+ increased further and the macrophages endocytosis enhanced the lysosomal pH fluctuated quickly, which was benefit for lysosomal content excretion, thus enhanced the lysosome activity.
7.Dosimetric Comparison of Inverse Three-Dimensional Conformal Radiotherapy and Intensity Modulated Radiotherapy for Non-Ssmall Cell Lung Cancer
Fuli ZHANG ; Weidong XU ; Junmao GAO ; Jianping CHEN ; Ping WANG ; Mingmin ZHENG
Chinese Journal of Medical Physics 2010;27(2):1704-1707,1720
Objective: To compare inverse three-dimensional conformal radiotherapy (Inv 3D-CRT) and intensity modulated ra-diotherapy (IMRT) for non-small cell lung cancer. Methods: For a cohort of 10 patients, Inv 3D-CRT and three groups of IMRT plannings were designed for per patient. The prescribed dose was 60 Gy/2 Gy/30f, 95% of the planning target volume received this dose. Dose was computed with a commercially available TPS using convolution/superposition (CS) algorithm. Plans were compared according to the PTV_(95)V_(20) ratio (PTV_(95)V_(20)) and D_(max)-D_(min). Results: Compared with Inv 3D-CRT, the PTV_(95)V_(20) ratio of three groups of IMRT increased by 1.08 (P = 0.014), 0.72 (P = 0.089) and 0.42 (P = 0.318), respectively. Conclusions: For NSCLC, IMRT can reduce the dose to the lungs compared with inverse 3D-CRT by improving the conformity of the plan and is worth spreading in clinical work.
8.Study on effect of base-material to distribution of microwave field
Jiancai ZHAI ; Liqung SHI ; Xianguang MA
Chinese Journal of Medical Physics 2000;17(4):225-226,228
A free space condition for the microwave radiation field for research will be needed, but different application microwave rields are not easy to satisfy this condition for the existence of interfaces of different medium. In the research, metal materials, insulator materials and ground materials are used as base-material to examine their effects upon the distribution of microwave field. Some rules are discovered.
9.Study on distribution of blood pressure in the cardiovascular system of rat
Qiushi ZHANG ; You ZHANG ; Yuming II ; Cheng ZHANG
Chinese Journal of Medical Physics 2000;17(4):243-244,246,248
Purpose:To study the distribution of blood pressure in the cardiovascular system of rat. Method:The experimental animal is Wistar rat (n=lS). The blood pressure in different parts of the cardiovascular system were recorded with a 4-channel polygraph system under closing condition. This method is more exact than that of manometer. Results:Our experiments demonstrated the following distribution of blood pressure in the cardiovascular system of rat. (1) The left ventricular systolic pressure(LVSP ) was 145.00+15.16 mmHg and the aortal systolic pressure(ASP ) was 126.87+11.16 mmHg. The LVSP was higher than ASP. The right ventricular systolic pressure(RVSP ) was 35.04+3.95 mrnHg and the pulmonary arterial systolic pressure(PASP) was 27.0313.46 mmHg. The RVSP was higher than PASP. This distribution of blood pressure was different with human. (2) On Value and range, the blood pressure in vascular system of rat (including A SP、A DP、MA P、PA SP、PA DP、MPA P、CVP、 WP)were clese to human. Conclusion: (1) The LVSPwas higher than ASP and the RVSP was higher than PASP. This distribution of blood pressure of rat was different with human. (2) The LVSP and RVSP of rat were higher when compared with human and the blood pressure distribution of other parts in the vascular system of rat was close to human
10.Research of Functional Connectivity Based on Independent Component Analysis and Temporal Correlation Analysis
Xinmei XU ; Huinan WANG ; Wei HUANG
Chinese Journal of Medical Physics 2008;25(1):477-480,483
Objective: Combining spatial independent component analysis (sICA) with temporal correlation analysis to investigate the functional connectivity of human brain using resting state fMRI. Methods: First, activated area was localized by performing sICA on the data from block design run, then one of the activated brain areas was chosen as a region of interest (ROI)and low frequency correlations between ROI and other regions were calculated in resting state to detect the functional connectivity networks. To validate the method, neural connectivity to primary motor cortex was assessed using this method during a resting state. Results: Functional connectivity network of motor cortex was detected, including primary motor cortex (M1), supplementary motor area (SMA), primary sensory cortex (S1), dorsal premotor cortex (PMd) and posterior parietal somatosensory association area (PSAAp). The connectivity implied by the resting state correlation was far more similar to the connectivity established by non-imaging methods. Conclusion: Functional connectivity of human motor primary cortex was investigated by combining sICA with temporal correlation using resting fMRI data. It provided a simple and noninvasive method for the research of brain functional connectivity.