Brain death is defined as permanent loss of the brain functions. The evaluation of it has many meanings, such as the relief of organ transplantation stress and family burden. However, it is hard to be judged precisely. The standard clinical tests are expensive, time consuming and even dangerous, and some auxiliary methods have limitations. Functional near infrared spectroscopy (fNIRS), monitoring cerebral hemodynamic responses noninvasively, evaluate brain death in some papers published, but there is no discussion about which experimental mode can monitor brain death patient more sensitively. Here, we attempt to use our fNIRS to evaluate brain death and find which experimental mode is effective. In order to discuss the problem, we detected eleven brain death patients and twenty normal patients under natural state. They were provided different fraction of inspiration O2 (FIO2) in different phase. We found that the ratio of ∆[HbO2] (the concentration changes in oxyhemoglobin) to ∆[Hb] (the concentration changes in deoxyhemoglobin) in brain death patients is significantly higher than normal patients in FIO2 experiment. Combined with the data analysis result, restore oxygen change process and low-high-low paradigm is more sensitively.
Deep vein thrombosis (DVT), happening in inpatients usually and especially with the postoperative population, is a serious disease characterized by an increased incidence. The venography is the golden standard to diagnose DVT. However, it involves invasive contrast agent injection and give patients physical and mental pressure. Functional nearinfrared spectroscopy (fNIRS) has been reported recently to diagnose DVT. Thrombolytic therapy activates the dissolution system with an exogenous activator that dissolves coronary thrombosis. The vena cava filter is a medical filter used for the treatment of thrombosis and the prevention of pulmonary embolism. Here we attempt to use portable NIRS for the DVT monitoring in the whole process of vena cava filter implantation and thrombolytic treatment, and contrast the patients of untreated, vena cava filter implantation and thrombolytic treatment. 19 DVT patients and 12 normal subjects were recruited. Thereinto, 7 patients have taken vena cava filter implantation, and 6 patients have taken the thrombolytic treatment. It was found that deoxyhemoglobins (Δ[Hb]) fluctuates and even increases in DVT. After vena cava filter implantation, Δ[Hb] increases first, then decreases. However, it emerges the rising trend and converge to the curves of normal subjects in thrombolytic treatment. The oxyhemoglobins (Δ[HbO2]) emerges opposite trend in most paradigms. The findings reveal the potential of fNIRS for monitoring DVT and therapeutic effect evaluation of thrombolysis and vena cava filters.
KEYWORDS: Photons, Head, Tissue optics, Absorption, Monte Carlo methods, Near infrared spectroscopy, Brain activation, Sensors, 3D modeling, Data modeling
Near infrared spectroscopy (NIRS) and diffuse correlation spectroscopy (DCS) has been used to measure brain activation, which are clinically important. Monte Carlo simulation has been applied to the near infrared light propagation model in biological tissue, and has the function of predicting diffusion and brain activation. However, previous studies have rarely considered hair and hair follicles as a contributing factor. Here, we attempt to use MCVM (Monte Carlo simulation based on 3D voxelized media) to examine light transmission, absorption, fluence, spatial sensitivity distribution (SSD) and brain activation judgement in the presence or absence of the hair follicles. The data in this study is a series of high-resolution cryosectional color photograph of a standing Chinse male adult. We found that the number of photons transmitted under the scalp decreases dramatically and the photons exported to detector is also decreasing, as the density of hair follicles increases. If there is no hair follicle, the above data increase and has the maximum value. Meanwhile, the light distribution and brain activation have a stable change along with the change of hair follicles density. The findings indicated hair follicles make influence of NIRS in light distribution and brain activation judgement.
KEYWORDS: Geography, 3D modeling, Information technology, Analytical research, Mathematical modeling, Systems modeling, Information science, Photonics, Visualization, Current controlled current source
The paper describes the model of research and method of investment environment evaluation of China and introduces the
related geography information system frame. Through the analysis and research of information relatedness law of things,
the relationship of complicated and instantaneous of information can be held. This can lead to the research thought and
method of complicated problems solution such as investment environment evaluation and sustained development. And it
can be used to simulate, evaluate and forecast the situation of regional macro nature, society, economics and investment
environment evaluation through the synergy application of relevant information technology. It can serve well to regional
sustained development.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.