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Sample records for non-invasive blood perfusion

  1. Non-invasive monitoring of peripheral perfusion: an exploration of non-invasive peripheral perfusion monitoring for applications in research & healthcare

    OpenAIRE

    Blaxter, Laurence

    2015-01-01

    The need for real-time, prognostic perfusion data has been widely recognised in clinical practice and academia. Perfusion, the volumetric blood low to tissue, is an important tool for haemodynamic monitoring, since perfusion adequacy is vital to tissue health. Perfusion can serve as both a diagnostic indicator and a fundamental research tool. However, lack of a low cost, easily applied, and non-invasive sensor technology capable of measuring peripheral perfusion in absolute volumetric units i...

  2. Acute changes in liver tumour perfusion measured non-invasively with arterial spin labelling

    Science.gov (United States)

    Johnson, S Peter; Ramasawmy, Rajiv; Campbell-Washburn, Adrienne E; Wells, Jack A; Robson, Mathew; Rajkumar, Vineeth; Lythgoe, Mark F; Pedley, R Barbara; Walker-Samuel, Simon

    2016-01-01

    Background: Non-invasive measures of tumour vascular perfusion are desirable, in order to assess response to vascular targeting (or modifying) therapies. In this study, hepatic arterial spin labelling (ASL) magnetic resonance imaging (MRI) was investigated to measure acute changes in perfusion of colorectal cancer in the liver, in response to vascular disruption therapy with OXi4503. Methods: SW1222 and LS174T tumours were established in the liver of MF1 nu/nu mice via intrasplenic injection. Perfusion and R2* MRI measurements were acquired with an Agilent 9.4T horizontal bore scanner, before and at 90 min after 40 mg kg−1 OXi4503. Results: A significant decrease in SW1222 tumour perfusion was observed (−43±33%, Pchange in tumour perfusion and the proximity to large vessels, with pre-treatment blood flow predictive of subsequent response. Histological evaluation confirmed the onset of necrosis and evidence of heterogeneous response between tumour deposits. Conclusions: Hepatic ASL-MRI can detect acute response to targeted tumour vascular disruption entirely non-invasively. Hepatic ASL of liver tumours has potential for use in a clinical setting. PMID:27031853

  3. Non-Invasive Optical Blood Glucose Measurement

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    Megha C.Pande

    2013-07-01

    Full Text Available The method for noninvasively blood glucose monitoring system is discussed in this paper. Lot of research work has been done in developing the device which is completely noninvasive to avoid the pros & cons because of frequent pricking. In this paper we are trying to analyze the noninvasive blood glucose measurement study in the near infrared region which is the most suitable region for blood glucose measurement. For this purpose we use a technique which is similar to pulseoximetry based on near infrared spectrometry .An infrared light of particular wavelength is passed through fingertip containing an arterial pulse component are derived,thus minimizing influences of basal components such as resting blood volume,skin, muscle and bone.

  4. Non-invasive imaging in detecting myocardial viability: Myocardial function versus perfusion

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    Iqbal A. Elfigih

    2014-12-01

    Full Text Available Coronary artery disease (CAD is the most prevalent and single most common cause of morbidity and mortality [1] with the resulting left ventricular (LV dysfunction an important complication. The distinction between viable and non-viable myocardium in patients with LV dysfunction is a clinically important issue among possible candidates for myocardial revascularization. Several available non-invasive techniques are used to detect and assess ischemia and myocardial viability. These techniques include echocardiography, radionuclide images, cardiac magnetic resonance imaging and recently myocardial computed tomography perfusion imaging. This review aims to distinguish between the available non-invasive imaging techniques in detecting signs of functional and perfusion viability and identify those which have the most clinical relevance in detecting myocardial viability in patients with CAD and chronic ischemic LV dysfunction. The most current available studies showed that both myocardial perfusion and function based on non-invasive imaging have high sensitivity with however wide range of specificity for detecting myocardial viability. Both perfusion and function imaging modalities provide complementary information about myocardial viability and no optimum single imaging technique exists that can provide very accurate diagnostic and prognostic viability assessment. The weight of the body of evidence suggested that non-invasive imaging can help in guiding therapeutic decision making in patients with LV dysfunction.

  5. Injury and repair in perinatal brain injury: Insights from non-invasive MR perfusion imaging.

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    Wintermark, Pia

    2015-03-01

    Injury to the developing brain remains an important complication in critically ill newborns, placing them at risk for future neurodevelopment impairments. Abnormal brain perfusion is often a key mechanism underlying neonatal brain injury. A better understanding of how alternations in brain perfusion can affect normal brain development will permit the development of therapeutic strategies that prevent and/or minimize brain injury and improve the neurodevelopmental outcome of these high-risk newborns. Recently, non-invasive MR perfusion imaging of the brain has been successfully applied to the neonatal brain, which is known to be smaller and have lower brain perfusion compared to older children and adults. This article will present an overview of the potential role of non-invasive perfusion imaging by MRI to study maturation, injury, and repair in perinatal brain injury and demonstrate why this perfusion sequence is an important addition to current neonatal imaging protocols, which already include different sequences to assess the anatomy and metabolism of the neonatal brain.

  6. [The peripheral perfusion pressure: a new non-invasive parameter for the circulatory monitoring of patients (author's transl)].

    Science.gov (United States)

    Huch, A; Lübbers, D W; Huch, R

    1975-01-01

    Heating of a skin area to a temperature of 42 degrees to 44 degrees C produces a certain physiological condition which induces maximal vasodilatation. Detailed experiments have shown that local peripheral vascular resistance of such an area remains constant for several hours. The flow in this area is proportional to the actual perfusion pressure. Relative flow was measured by means of a new type of electrode fixed to the skin like and ECG electrode, and compared with simultaneous intra-arterial blood pressure measruements. The changes in arterial blood pressure were also recorded by the skin electrode. This new parameter is defined as "peripheral perfusion pressure". It is appropiate for non-invasive continuous monitoring of the circulatory system of patients.

  7. An optical approach for non-invasive blood clot testing

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    Kalchenko, Vyacheslav; Brill, Alexander; Fine, Ilya; Harmelin, Alon

    2007-02-01

    Physiological blood coagulation is an essential biological process. Current tests for plasma coagulation (clotting) need to be performed ex vivo and require fresh blood sampling for every test. A recently published work describes a new, noninvasive, in vivo approach to assess blood coagulation status during mechanical occlusion1. For this purpose, we have tested this approach and applied a controlled laser beam to blood micro-vessels of the mouse ear during mechanical occlusion. Standard setup for intravital transillumination videomicroscopy and laser based imaging techniques were used for monitoring the blood clotting process. Temporal mechanical occlusion of blood vessels in the observed area was applied to ensure blood flow cessation. Subsequently, laser irradiation was used to induce vascular micro-injury. Changes in the vessel wall, as well as in the pattern of blood flow, predispose the area to vascular thrombosis, according to the paradigm of Virchow's triad. In our experiments, two elements of Virchow's triad were used to induce the process of clotting in vivo, and to assess it optically. We identified several parameters that can serve as markers of the blood clotting process in vivo. These include changes in light absorption in the area of illumination, as well as changes in the pattern of the red blood cells' micro-movement in the vessels where blood flow is completely arrested. Thus, our results indicate that blood coagulation status can be characterized by non-invasive, in vivo methodologies.

  8. Non-invasive Blood Glucose Quantification Using a Hybrid Sensor

    Directory of Open Access Journals (Sweden)

    Sundararajan JAYAPAL

    2009-02-01

    Full Text Available Diabetes Mellitus is a group of metabolic diseases characterized by high blood sugar (glucose levels which result from defects in insulin secretion. It is very important for the diabetics and normal people to have a correct blood glucose level. The HbA1c test is the most preferred test by renowned doctors for glucose quantification. But this test is an invasive one. At present, there are many available techniques for this purpose but these are mostly invasive or minimally non-invasive and most of these are under research. Among the different methods available, the photo acoustic (PA methods provide a reliable solution since the acoustical energy loss is much less compared to the optical or other techniques. Here a novel framework is presented for blood glucose level measurement using a combination of the HbA1c test and a PA method to get an absolutely consistent and precise, non-invasive technique. The setup uses a pulsed laser diode with pulse duration of 5-15 ns and at a repetition rate of 10 Hz as the source. The detector setup is based on the piezoelectric detection. It consists of a ring detector that includes two double ring sensors that are attached to the ring shaped module that can be worn around the finger. The major aim is to detect the photo acoustic signals from the glycated hemoglobin with the least possible error. The proposed monitoring system is designed with extreme consideration to precision and compatibility with the other computing devices. The results obtained in this research have been studied and analyzed by comparing these with those of in-vitro techniques like the HPLC. The comparison has been plotted and it shows a least error. The results also show a positive drive for using this concept as a basis for future extension in quantifying the other blood components.

  9. Tomographic non-invasive measurements of regional cerebral blood flow

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    Hedde, J.P.; Reischies, W.; Fiegler, R.; Felix, H.; Helmchen, H.; Kanowski, S.

    1984-02-01

    The measurement of the regional cerebral blood flow by means of the dynamic single-photon-emission-computed tomography is a method of examination which is completely free of risk for the patient, causes no inconvenience and can be repeated whenever it seems necessary. This method gives a quantitative explanation for the distribution of the effective cerebral perfusion and can only be substituted by the very complicated positron-emission-computed tomography. As well as the exact assessment of the hemodynamic relevance of cerebral vascular disease, this method enables us to prove whether or not in various types of psychiatric disorders an interference in the regional perfusion exists. This method can also contribute to the clarification of pathogenic mechanisms, as well as to the nosological classification of specific psychopathological conditions.

  10. Blood biomarkers for the non-invasive diagnosis of endometriosis

    NARCIS (Netherlands)

    Nisenblat, Vicki; Bossuyt, Patrick M. M.; Shaikh, Rabia; Farquhar, Cindy; Jordan, Vanessa; Scheffers, Carola S.; Mol, Ben Willem J.; Johnson, Neil; Hull, M. Louise

    2016-01-01

    Background About 10% of reproductive-aged women suffer from endometriosis, a costly chronic disease causing pelvic pain and subfertility. Laparoscopy is the gold standard diagnostic test for endometriosis, but is expensive and carries surgical risks. Currently, there are no non-invasive or minimally

  11. Non-invasive spectroscopy of transfusable red blood cells stored inside sealed plastic blood-bags.

    Science.gov (United States)

    Buckley, K; Atkins, C G; Chen, D; Schulze, H G; Devine, D V; Blades, M W; Turner, R F B

    2016-03-07

    After being separated from (donated) whole blood, red blood cells are suspended in specially formulated additive solutions and stored (at 4 °C) in polyvinyl chloride (PVC) blood-bags until they are needed for transfusion. With time, the prepared red cell concentrate (RCC) is known to undergo biochemical changes that lower effectiveness of the transfusion, and thus regulations are in place that limit the storage period to 42 days. At present, RCC is not subjected to analytical testing prior to transfusion. In this study, we use Spatially Offset Raman Spectroscopy (SORS) to probe, non-invasively, the biochemistry of RCC inside sealed blood-bags. The retrieved spectra compare well with conventional Raman spectra (of sampled aliquots) and are dominated by features associated with hemoglobin. In addition to the analytical demonstration that SORS can be used to retrieve RCC spectra from standard clinical blood-bags without breaking the sterility of the system, the data reveal interesting detail about the oxygenation-state of the stored cells themselves, namely that some blood-bags unexpectedly contain measurable amounts of deoxygenated hemoglobin after weeks of storage. The demonstration that chemical information can be obtained non-invasively using spectroscopy will enable new studies of RCC degeneration, and points the way to a Raman-based instrument for quality-control in a blood-bank or hospital setting.

  12. Non-invasive perfusion imaging by modified STAR using asymmetric inversion slabs (ASTAR)

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    Kimura, Tokunori [Toshiba Nasu Works, Otawara, Tochigi (Japan)

    2000-12-01

    Arterial spin labeling (ASL) such as STAR, EPISTAR, and FAIR have been used as imaging techniques of tissue perfusion and blood vessels (in MRA). We have developed 'ASTAR', a modified version of STAR by using asymmetric inversion slabs. ASTAR solves the problems of suppression of venous inflow and subtraction error of stationary tissue signal caused by the imbalance of signal variations. The signal variations are dependent on MT effects. In order to avoid overlapping the control slab to the tissue (including large veins), the control and tag slabs are arranged asymmetrically to preserve the same offset of modulation frequency. We evaluated both the subtraction error caused by the MT effects, and the imperfection of an IR slab using a stationary phantom. We then measured the vessel signal on the brain of a volunteer, using the above methods. Two indexes were used for the evaluation: ASL signal to control signal ratio (ASLR [%]=100*deltaS/S{sub cont}) and ASL signal to noise ratio (ASLNR=delatS/Noise) where deltaS=|S{sub cont}-S{sub tag}|. Phantom study: each ASLR and ASLNR between ASTAR and EPISTAR was comparable and showed a decrease in noise signal level. This means that the ASL signal from the stationary tissue with an imbalance in MT effects and the imperfection in inversion slab profiles were cancelled out almost perfectly. When calculating CBF, ASLR for zero perfusion stationary tissue should be below 0.1%. We were able to satisfy this requirement in our ASTAR experiment. ASLR and ASLNR in FAIR were 40% larger than in EPISTAR and ASTAR. Volunteer brain study: compared with each ASL image, the MT effects were cancelled out in EPISTAR and ASTAR. Veins (sagittal sinus etc) disappeared in STAR and ASTAR, but were visible in EPISTAR and FAIR. Perfusion signals were similar in ASTAR and EPISTAR, indicating that both cancellation of MT effects and venous inflow from the opposite side of the tag were suppressed in ASTAR. In conclusion, ASTAR is a practical

  13. Finger temperature controller for non-invasive blood glucose measurement

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    Zhang, Xiqin; Ting, Choon Meng; Yeo, Joon Hock

    2010-11-01

    Blood glucose level is an important parameter for doctors to diagnose and treat diabetes. The Near-Infra-Red (NIR) spectroscopy method is the most promising approach and this involves measurement on the body skin. However it is noted that the skin temperature does fluctuate with the environmental and physiological conditions and we found that temperature has important influences on the glucose measurement. In-vitro and in-vivo investigations on the temperature influence on blood glucose measurement have been carried out. The in-vitro results show that water temperature has significant influence on water absorption. Since 90% of blood components are water, skin temperature of measurement site has significant influence on blood glucose measurement. Also the skin temperature is related to the blood volume, blood volume inside capillary vessels changes with skin temperature. In this paper the relationship of skin temperature and signal from the skin and inside tissue was studied at different finger temperatures. Our OGTT (oral glucose tolerance test) trials results show the laser signals follow the skin temperature trend and the correlation of signal and skin temperature is much stronger than the correlation of signal and glucose concentration. A finger heater device is designed to heat and maintain the skin temperature of measurement site. The heater is controlled by an electronic circuit according to the skin temperature sensed by a thermocouple that is put close to the measurement site. In vivo trials were carried out and the results show that the skin temperature significantly influences the signal fluctuations caused by pulsate blood and the average signal value.

  14. Non-invasive assessment of pulmonary blood supply after staged repair of pulmonary atresia.

    OpenAIRE

    Del Torso, S.; Kelly, M J; Kalff, V; Stellin, G; Mee, R B; Venables, A W

    1985-01-01

    Radionuclide studies were performed to determine pulmonary blood flow in six children who had undergone surgery for pulmonary atresia, ventricular septal defect, and hypoplastic pulmonary arteries with or without major aortopulmonary collateral arteries. Lung blood flow was assessed from both particle perfusion lung scans and the pulmonary and systemic phase of a radionuclide dynamic flow study. Five patients had perfusion defects identified on the particle perfusion lung scan. In three of th...

  15. An Investigation of Pulse Transit Time as a Non-Invasive Blood Pressure Measurement Method

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    McCarthy, B M; O' Flynn, B; Mathewson, A, E-mail: brian.mccarthy@tyndall.ie [Tyndall National Institute, UCC, Lee Maltings, Prospect Row, Cork (Ireland)

    2011-08-17

    The objective of this paper is to examine the Pulse Transit Method (PTT) as a non-invasive means to track Blood Pressure over a short period of time. PTT was measured as the time it takes for an ECG R-wave to propagate to the finger, where it is detected by a photoplethysmograph sensor. The PTT method is ideal for continuous 24-hour Blood Pressure Measurement (BPM) since it is both cuff-less and non-invasive and therefore comfortable and unobtrusive for the patient. Other techniques, such as the oscillometric method, have shown to be accurate and reliable but require a cuff for operation, making them unsuitable for long term monitoring. Although a relatively new technique, the PTT method has shown to be able to accurately track blood pressure changes over short periods of time, after which re-calibration is necessary. The purpose of this study is to determine the accuracy of the method.

  16. Parametrically defined cerebral blood vessels as non-invasive blood input functions for brain PET studies

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    Asselin, Marie-Claude; Cunningham, Vincent J.; Amano, Shigeko; Gunn, Roger N.; Nahmias, Claude

    2004-03-01

    A non-invasive alternative to arterial blood sampling for the generation of a blood input function for brain positron emission tomography (PET) studies is presented. The method aims to extract the dimensions of the blood vessel directly from PET images and to simultaneously correct the radioactivity concentration for partial volume and spillover. This involves simulation of the tomographic imaging process to generate images of different blood vessel and background geometries and selecting the one that best fits, in a least-squares sense, the acquired PET image. A phantom experiment was conducted to validate the method which was then applied to eight subjects injected with 6-[18F]fluoro-L-DOPA and one subject injected with [11C]CO-labelled red blood cells. In the phantom study, the diameter of syringes filled with an 11C solution and inserted into a water-filled cylinder were estimated with an accuracy of half a pixel (1 mm). The radioactivity concentration was recovered to 100 ± 4% in the 8.7 mm diameter syringe, the one that most closely approximated the superior sagittal sinus. In the human studies, the method systematically overestimated the calibre of the superior sagittal sinus by 2-3 mm compared to measurements made in magnetic resonance venograms on the same subjects. Sources of discrepancies related to the anatomy of the blood vessel were found not to be fundamental limitations to the applicability of the method to human subjects. This method has the potential to provide accurate quantification of blood radioactivity concentration from PET images without the need for blood samples, corrections for delay and dispersion, co-registered anatomical images, or manually defined regions of interest.

  17. Ability of non-invasive intermittent blood pressure monitoring and a continuous non-invasive arterial pressure monitor (CNAP™) to provide new readings in each 1-min interval during elective caesarean section under spinal anaesthesia.

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    McCarthy, T; Telec, N; Dennis, A; Griffiths, J; Buettner, A

    2012-03-01

    We compared the ability of automated non-invasive intermittent oscillometric blood pressure monitoring with a new device, CNAP(TM) (continuous non-invasive arterial pressure) to provide a new blood pressure reading in each 1-min interval between spinal anaesthesia and delivery during caesarean section. We also compared the accuracy of continuous non-invasive arterial pressure readings with non-invasive blood pressure measurements before spinal anaesthesia. Fifty-nine women participated. The non-invasive and continuous non-invasive monitors displayed new blood pressure readings in a mean of 82% (11%) and 83% (13%) (p = 0.97) of the one-minute intervals between spinal anaesthesia and delivery, respectively. Continuous non-invasive arterial pressure was more likely to fail on two or more consecutive minutes (p=0.001). From the pre-spinal readings, the mean bias, defined as non-invasive-continuous non-invasive arterial pressure, and limits of agreement (±2SD mean bias) for systolic, diastolic and mean blood pressure respectively were +1.3 (±26.0), -2.9 (±21.8) and +2.6 (±20.4) mmHg. The new monitor has disadvantages compared with conventional non-invasive intermittent blood pressure monitoring. Anaesthesia © 2012 The Association of Anaesthetists of Great Britain and Ireland.

  18. Fetal cells in maternal blood: state of the art for non-invasive prenatal diagnosis.

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    Ho, S S; O'Donoghue, K; Choolani, M

    2003-09-01

    In Singapore, 1 in 5 pregnancies occur in mothers > 35 years old and genetic diseases, such as thalassaemia, are common. Current methods for the diagnosis of aneuploidy and monogenic disorders require invasive testing by amniocentesis, chorion villus biopsy or fetal blood sampling. These tests carry a procedure-related risk of miscarriage that is unacceptable to many couples. Development of non-invasive methods for obtaining intact fetal cells would allow accurate prenatal diagnosis for aneuploidy and single gene disorders, without the attendant risks associated with invasive testing, and would increase the uptake of prenatal diagnosis by women at risk. Isolation of fetal erythroblasts from maternal blood should allow accurate non-invasive prenatal diagnosis of both aneuploidies and monogenic disorders. Expression of gamma-globin in maternal erythroblasts and the inability to locate fetal erythroblasts reliably in all pregnancies have prevented its clinical application. In the absence of a highly specific fetal cell marker, enrichment, identification and diagnosis--the 3 components of non-invasive prenatal diagnosis--have clearly defined objectives. Since fetal cells are rare in maternal blood, the sole purpose of enrichment is yield--to recover as many fetal cells as possible--even if purity is compromised at this stage. In contrast, the primary goal of identification is specificity; absolute certainty of fetal origin is required at this stage if the ultimate objective of diagnosis, accuracy, is to be achieved. This review summarises the current state of the art of non-invasive prenatal diagnosis using fetal erythroblasts enriched from maternal blood.

  19. Rheoencephalography (REG) as a Non-Invasive Monitoring Alternative for the Assessment of Brain Blood Flow

    Science.gov (United States)

    2004-09-01

    bioimpedance (rheoencephalography - REG) measurement as a non-invasive, continuous method for assessing the status of cerebral blood flow (CBF) in combat...Dunster KR, Colditz PB, Ward LC. Noninvasive measurement of cerebral bioimpedance for detection of cerebral edema in the neonatal piglet. Brain Res...REG measurements and DC impedance (Ro) were recorded simultaneously on a portable IBM compatible computer using CODAS (DATAQ, Inc., Akron, OH) data

  20. Non-invasive blood glucose detection system based on conservation of energy method.

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    Zhang, Yang; Zhu, Jian-Ming; Liang, Yong-Bo; Chen, Hong-Bo; Yin, Shi-Min; Chen, Zhen-Cheng

    2017-02-01

    The most common method used for minimizing the occurrence of diabetes complications is frequent glucose testing to adjust the insulin dose. However, using blood glucose (BG) meters presents a risk of infection. It is of great importance to develop non-invasive BG detection techniques. To realize high-accuracy, low-cost and continuous glucose monitoring, we have developed a non-invasive BG detection system using a mixed signal processor 430 (MSP430) microcontroller. This method is based on the combination of the conservation-of-energy method with a sensor integration module, which collects physiological parameters, such as the blood oxygen saturation (SPO2), blood flow velocity and heart rate. New methods to detect the basal metabolic rate (BMR) and BV are proposed, which combine the human body heat balance and characteristic signals of photoplethysmography as well dual elastic chambers theory. Four hundred clinical trials on real-time non-invasive BG monitoring under suitable experiment conditions were performed on different individuals, including diabetic patients, senior citizens and healthy adults. A multisensory information fusion model was applied to process these samples. The algorithm (we defined it as DCBPN algorithm) applied in the model combines a decision tree and back propagation neural network, which classifies the physiological and environmental parameters into three categories, and then establishes a corresponding prediction model for the three categories. The DCBPN algorithm provides an accuracy of 88.53% in predicting the BG of new samples. Thus, this system demonstrates a great potential to reliably detect BG values in a non-invasive setting.

  1. Comparison between invasive and non-invasive blood pressure in young, middle and old age.

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    Liu, Bing; Li, Qiao; Qiu, Peng

    2016-06-01

    We aimed to compare simultaneous invasive and non-invasive blood pressure (IBP and NIBP) measurements in young, middle and old age using the data from the Multiparameter Intelligent Monitoring in Intensive Care II (MIMIC II) database. In total, 23,679 blood pressure measurements were extracted from 742 patients, divided into three groups of young, middle and old age. IBP-NIBP differences in systolic/diastolic blood pressure (SBP/DBP) were 0.1 ± 16.5 mmHg/11.0 ± 12.2 mmHg in young age, -2.9 ± 19.8 mmHg/6.9 ± 17.5 mmHg in middle age and -3.2 ± 29.3 mmHg/8.5 ± 19.8 mmHg in old age. The mean and standard deviation (SD) of invasive systolic blood pressure (ISBP)-non-invasive systolic blood pressure (NISBP) differences increased from young to middle then to old age, and the SD of invasive diastolic blood pressure (IDBP)-non-invasive diastolic blood pressure (NIDBP) differences also increased with age. In young, middle and old age, the correlation coefficients were 0.86, 0.79 and 0.53, respectively, between ISBP and NISBP, and 0.78, 0.78 and 0.41 between IDBP and NIDBP. In conclusion, IBP showed good correlation with NIBP in each age category. The agreement between IBP and NIBP measurements was influenced by age category.

  2. Research of transmissive near infrared spectroscopy for non-invasive blood glucose measurement

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    Yang, Wenming; Liao, Ningfang; Li, Yasheng; Shao, Liwei; Huang, Dehuang

    2016-10-01

    Near infrared (NIR) has prospectively applied in non-invasive blood glucose measurement due to glucose absorption among the 1.0-2.5m spectral bands. However, this significant technology is hard to be developed because of other blood components and low signal-to-noise ratio (SNR). In this work, we presented a non-invasive glucose measurement system using Fourier transform spectrometer which will work in fingertips or other human body tissues. A refrigerated InGaAs detector with high quantum efficiency performing well in the range of 1.0-1.7μm wavelength is used to acquire transmissive radiation. Preliminary experiment investigations were set up to test glucose levels of aqueous solutions with different concentrations. The analytical modeling of the interferogram data is based on arithmetic Fourier transform and supported by the curvilineal characterization. Experimental results show the variation of light intensity among different glucose concentrations and emphasize the obvious absorption of glucose in NIR wave-range. This study confirms the suitability that NIR can be developed in non-invasive glucose measurement.

  3. Feasibility of non-invasive optical blood-glucose detection using overtone circular dichroism

    CERN Document Server

    Hokr, Brett H; Meng, Zhaokai; Petrov, Georgi I; Yakovlev, Vladislav V

    2016-01-01

    Diabetes is one of the most debilitating and costly diseases currently plaguing humanity. It is a leading cause of death and dismemberment in the world, and we know how to treat it. Accurate, continuous monitoring and control of blood glucose levels via insulin treatments are widely known to mitigate the majority of detrimental effects caused by the disease. The primary limitation of continuous glucose monitoring is patient non-compliance due to the unpleasant nature of "finger-stick" testing methods. This limitation can be largely, or even completely, removed by non-invasive testing methods. In this report, we demonstrate the vibrational overtone circular dichroism properties of glucose and analyze its use as a method of non-invasive glucose monitoring, capable of assuaging this trillion dollar scourge.

  4. Proposed Application of Fast Fourier Transform in Near Infra Red Based Non Invasive Blood Glucose Monitoring System

    Science.gov (United States)

    Jenie, R. P.; Iskandar, J.; Kurniawan, A.; Rustami, E.; Syafutra, H.; Nurdin, N. M.; Handoyo, T.; Prabowo, J.; Febryarto, R.; Rahayu, M. S. K.; Damayanthi, E.; Rimbawan; Sukandar, D.; Suryana, Y.; Irzaman; Alatas, H.

    2017-03-01

    Worldwide emergence of glycaemic status related health disorders, such as diabetes and metabolic syndrome, is growing in alarming rate. The objective was to propose new methods for non invasive blood glucose level measurement system, based on implementation of Fast Fourier Transform methods. This was an initial-lab-scale-research. Data on non invasive blood glucose measurement are referred from Scopus, Medline, and Google Scholar, from 2011 until 2016, and was used as design references, combined with in house verification. System was developed in modular fashion, based on aforementioned compiled references. Several preliminary tests to understand relationship between LED and photo-diode responses have been done. Several references were used as non invasive blood glucose measurement tools design basis. Solution is developed in modular fashion. we have proven different sensor responses to water and glucose. Human test for non invasive blood glucose level measurement system is needed.

  5. Influence of cholesterol on non-invasive blood glucose sensing studied with NIR spectroscopy

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    Jiang, Jingying; Zhang, Lingling; Gong, Qiliang; Xu, Kexin

    2011-03-01

    There is a growing body of studies suggesting that NIR spectroscopy is feasible to be used to non-invasive blood glucose sensing. However, previous results reported that blood components are very complicated and in which glucose concentration is relatively low. This feature limited the practical application of NIR spectroscopy to in vivo blood glucose detection. This talk aims to elucidate how the cholesterol influences blood glucose sensing. Spectroscopic measurements show that cholesterol appears the similar absorbance peaks to those of glucose within NIR range. Furthermore, PLS modelling results demonstrate that the measurement concentrations of glucose are on the high side while containing cholesterol. For example, when the cholesterol concentration is 200mg/dl, the measurement result of glucose with near-infrared spectroscopy will increase 7.961882mg/dl comparing to cholesterol-free glucose solution. Therefore, it is necessary to take steps to reduce cholesterol's effects.

  6. Research on the multiple linear regression in non-invasive blood glucose measurement.

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    Zhu, Jianming; Chen, Zhencheng

    2015-01-01

    A non-invasive blood glucose measurement sensor and the data process algorithm based on the metabolic energy conservation (MEC) method are presented in this paper. The physiological parameters of human fingertip can be measured by various sensing modalities, and blood glucose value can be evaluated with the physiological parameters by the multiple linear regression analysis. Five methods such as enter, remove, forward, backward and stepwise in multiple linear regression were compared, and the backward method had the best performance. The best correlation coefficient was 0.876 with the standard error of the estimate 0.534, and the significance was 0.012 (sig. regression equation was valid. The Clarke error grid analysis was performed to compare the MEC method with the hexokinase method, using 200 data points. The correlation coefficient R was 0.867 and all of the points were located in Zone A and Zone B, which shows the MEC method provides a feasible and valid way for non-invasive blood glucose measurement.

  7. Modelling, verification, and calibration of a photoacoustics based continuous non-invasive blood glucose monitoring system.

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    Pai, Praful P; Sanki, Pradyut K; Sarangi, Satyabrata; Banerjee, Swapna

    2015-06-01

    This paper examines the use of photoacoustic spectroscopy (PAS) at an excitation wavelength of 905 nm for making continuous non-invasive blood glucose measurements. The theoretical background of the measurement technique is verified through simulation. An apparatus is fabricated for performing photoacoustic measurements in vitro on glucose solutions and in vivo on human subjects. The amplitude of the photoacoustic signals measured from glucose solutions is observed to increase with the solution concentration, while photoacoustic amplitude obtained from in vivo measurements follows the blood glucose concentration of the subjects, indicating a direct proportionality between the two quantities. A linear calibration method is applied separately on measurements obtained from each individual in order to estimate the blood glucose concentration. The estimated glucose values are compared to reference glucose concentrations measured using a standard glucose meter. A plot of 196 measurement pairs taken over 30 normal subjects on a Clarke error grid gives a point distribution of 82.65% and 17.35% over zones A and B of the grid with a mean absolute relative deviation (MARD) of 11.78% and a mean absolute difference (MAD) of 15.27 mg/dl (0.85 mmol/l). The results obtained are better than or comparable to those obtained using photoacoustic spectroscopy based methods or other non-invasive measurement techniques available. The accuracy levels obtained are also comparable to commercially available continuous glucose monitoring systems.

  8. Evaluating the culture of fetal erythroblasts from maternal blood for non-invasive prenatal diagnosis.

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    Chen, H; Griffin, D K; Jestice, K; Hackett, G; Cooper, J; Ferguson-Smith, M A

    1998-09-01

    Fetal erythroblasts circulating in maternal blood are important candidate cells for non-invasive prenatal diagnosis. We have cultured erythroblasts from 16 maternal blood samples, both with and without prior enrichment by magnetic activated cell sorting (MACS), in a semi-solid medium containing growth factors. Individual colonies were examined by PCR with sex chromosome-specific primers and microsatellite marker primers. No conclusive Y-chromosome specific amplification could be demonstrated in any of the 16 cases, even when the mother was confirmed to be carrying a male fetus. All colonies tested by microsatellite marker PCR were of maternal origin. Our results suggest that the probability of obtaining fetal colonies from fetal erythroblasts circulating in maternal blood is very low and that approaches for culturing fetal erythroblasts in vitro cannot yet be used reliably for prenatal diagnosis using current methods for fetal cell enrichment.

  9. Non-invasive blood glucose monitoring with Raman spectroscopy: prospects for device miniaturization

    Science.gov (United States)

    Wróbel, M. S.

    2016-01-01

    The number of patients with diabetes has reached over 350 million, and still continues to increase. The need for regular blood glucose monitoring sparks the interest in the development of modern detection technologies. One of those methods, which allows for noninvasive measurements, is Raman spectroscopy. The ability of infrared light to penetrate deep into tissues allows for obtaining measurements through the skin without its perforation. This paper presents the limitations and possibilities of non-invasive blood glucose monitoring with Raman spectroscopy. Especially focusing on the possibilities for device miniaturization. Such device incorporates a Raman spectrometer, a fiber-optical probe, and a computing device (microcontroller, smartphone, etc.) which calculates the glucose concentration using specialized algorithms. Simplification of device design, as well as turbidity correction technique and a new proposed method of synchronized detection are described.

  10. Limitations of stroke volume estimation by non-invasive blood pressure monitoring in hypergravity.

    Directory of Open Access Journals (Sweden)

    Olivier Manen

    Full Text Available Altitude and gravity changes during aeromedical evacuations induce exacerbated cardiovascular responses in unstable patients. Non-invasive cardiac output monitoring is difficult to perform in this environment with limited access to the patient. We evaluated the feasibility and accuracy of stroke volume estimation by finger photoplethysmography (SVp in hypergravity.Finger arterial blood pressure (ABP waveforms were recorded continuously in ten healthy subjects before, during and after exposure to +Gz accelerations in a human centrifuge. The protocol consisted of a 2-min and 8-min exposure up to +4 Gz. SVp was computed from ABP using Liljestrand, systolic area, and Windkessel algorithms, and compared with reference values measured by echocardiography (SVe before and after the centrifuge runs.The ABP signal could be used in 83.3% of cases. After calibration with echocardiography, SVp changes did not differ from SVe and values were linearly correlated (p<0.001. The three algorithms gave comparable SVp. Reproducibility between SVp and SVe was the best with the systolic area algorithm (limits of agreement -20.5 and +38.3 ml.Non-invasive ABP photoplethysmographic monitoring is an interesting technique to estimate relative stroke volume changes in moderate and sustained hypergravity. This method may aid physicians for aeronautic patient monitoring.

  11. Perfusion index versus non-invasive hemodynamic parameters during insertion of i-gel, classic laryngeal mask airway and endotracheal tube.

    Science.gov (United States)

    Atef, Hosam M; Fattah, Salah Abd; Gaffer, Mohammed Emad Abd; Al Rahman, Ahamed Abd

    2013-03-01

    Perfusion index (PI) is a non-invasive numerical value of peripheral perfusion obtained from a pulse oximeter. In this study, we evaluated the efficacy of PI for detecting haemodynamic stress responses to insertion of i-gel, laryngeal mask airway (LMA) and endotracheal tube and compare, its reliability with the conventional haemodynamic criteria in adults during general anaesthesia. Sixty patients scheduled for elective general surgery under general anaesthesia were randomised to three groups. (i-gel, LMA and ET groups (n=20/group). Heart rate (HR) (positive if ≥10 bpm), systolic blood pressure (SBP), diastolic blood pressure (DBP) (positive if ≥15 mm Hg) and PI (positive if ≤10%) were monitored for 5 min after insertion. SBP, DBP, HR and PI were measured before induction of anaesthesia and before and after insertion of the airway device. Insertion of airway devices produced significant increases in HR, SBP and DBP in LMA and ET groups. Moreover, PI was decreased significantly by 40%, 100% and 100% in the three groups. Using the PI criterion, the sensitivity was 100% (CI 82.4-100.0%). Regarding the SBP and DBP criterions, the sensitivity was 44.4% (CI 24.6-66.3%), 55.6% (CI 33.7-75.4%) respectively. Also, significant change in the mean PI over time (from pre-insertion value to the 1(st) min, 3(rd) min, until the 4(th) min after insertion without regard the device type), (P<0.001). PI is a reliable and easier alternative to conventional haemodynamic criteria for detection of stress response to insertion of i-gel, LMA and ET during propofol fentanyl isoflurane anaesthesia in adult patients.

  12. Perfusion index versus non-invasive hemodynamic parameters during insertion of i-gel, classic laryngeal mask airway and endotracheal tube

    Directory of Open Access Journals (Sweden)

    Hosam M Atef

    2013-01-01

    Full Text Available Background: Perfusion index (PI is a non-invasive numerical value of peripheral perfusion obtained from a pulse oximeter. In this study, we evaluated the efficacy of PI for detecting haemodynamic stress responses to insertion of i-gel, laryngeal mask airway (LMA and endotracheal tube and compare, its reliability with the conventional haemodynamic criteria in adults during general anaesthesia. Methods: Sixty patients scheduled for elective general surgery under general anaesthesia were randomised to three groups. (i-gel, LMA and ET groups ( n=20/group. Heart rate (HR (positive if ≥10 bpm, systolic blood pressure (SBP, diastolic blood pressure (DBP (positive if ≥15 mm Hg and PI (positive if ≤10% were monitored for 5 min after insertion. Main outcome measures: SBP, DBP, HR and PI were measured before induction of anaesthesia and before and after insertion of the airway device. Results: Insertion of airway devices produced significant increases in HR, SBP and DBP in LMA and ET groups. Moreover, PI was decreased significantly by 40%, 100% and 100% in the three groups. Using the PI criterion, the sensitivity was 100% (CI 82.4-100.0%. Regarding the SBP and DBP criterions, the sensitivity was 44.4% (CI 24.6-66.3%, 55.6% (CI 33.7-75.4% respectively. Also, significant change in the mean PI over time (from pre-insertion value to the 1 st min, 3 rd min, until the 4 th min after insertion without regard the device type, ( P<0.001. Conclusion: PI is a reliable and easier alternative to conventional haemodynamic criteria for detection of stress response to insertion of i-gel, LMA and ET during propofol fentanyl isoflurane anaesthesia in adult patients.

  13. Gingival crevicular blood: As a non-invasive screening tool for diabetes mellitus in dental clinics

    Directory of Open Access Journals (Sweden)

    Neema Shetty

    2013-01-01

    Full Text Available Background: A high number of patients with periodontitis may have undiagnosed diabetes. Self-monitoring devices provide a simple method for rapid monitoring of the glucose level in the blood by utilizing a blood sample from the finger, but this method requires a needle puncture to obtain blood. It is possible that gingival crevicular blood (GCB from routine periodontal probing may be a source of blood for glucose measurements. Aim: To establish whether GCB can be used as a non-invasive diagnostic aid in screening for diabetes mellitus during routine periodontal examination. Materials and Methods: The study involved 50 diabetics and 50 non-diabetics, with an age range of 26-66 years. Both diabetic and non-diabetic patients had moderate to severe gingivitis with at least one tooth in the maxillary anterior region showing bleeding upon probing. The Gingival Index and Oral Hygiene Index-Simplified were recorded. Blood oozing from the gingival sulcus/pocket following periodontal pocket probing was collected using a capillary tube and transferred to the test stick of a glucose self-monitoring device (Accu-Chek, Roche Diagnostic, Germany in patients with comparable gingival and oral hygiene status. This value was compared with the peripheral fingerstick blood glucose (PFBG value, which was obtained by pricking the finger tip at the same visit. Statistical analysis was performed using Pearson′s correlation coefficient. Result: There was no statistically significant difference between the gingival crevicular blood glucose (GCBG values and the PFBG values in both the diabetic (P = 0.129, NS and the non-diabetic (P = 0.503, NS groups. Karl Pearson′s product-moment correlation coefficient was calculated, which showed a positive correlation between the two measurements in the diabetic (r = 0.943 as well as the non-diabetic (r = 0.926 groups. Conclusion: The results suggest that GCB can be used as a non-invasive diagnostic aid in screening for diabetes

  14. Non-invasive evaluation of placental blood flow: lessons from animal models.

    Science.gov (United States)

    Mourier, E; Tarrade, A; Duan, J; Richard, C; Bertholdt, C; Beaumont, M; Morel, O; Chavatte-Palmer, P

    2017-03-01

    In human obstetrics, placental vascularisation impairment is frequent as well as linked to severe pathological events (preeclampsia and intrauterine growth restriction), and there is a need for reliable methods allowing non-invasive evaluation of placental blood flow. Uteroplacental vascularisation is complex, and animal models are essential for the technical development and safety assessment of these imaging tools for human clinical use; however, these techniques can also be applied in the veterinary context. This paper reviews how ultrasound-based imaging methods such as 2D and 3D Doppler can provide valuable insight for the exploration of placental blood flow both in humans and animals and how new approaches such as the use of ultrasound contrast agents or ultrafast Doppler may allow to discriminate between maternal (non-pulsatile) and foetal (pulsatile) blood flow in the placenta. Finally, functional magnetic resonance imaging could also be used to evaluate placental blood flow, as indicated by studies in animal models, but its safety in human pregnancy still requires to be confirmed. © 2017 Society for Reproduction and Fertility.

  15. Hybrid model of arm for analysis of regional blood oxygenation in non-invasive optical diagnostics

    Science.gov (United States)

    Nowocień, Sylwester; Mroczka, Janusz

    2017-06-01

    The paper presents a new comprehensive approach to modeling and analysis of processes occurring during the blood flow in the arm's small vessels as well as non-invasive measurement method of mixed venous oxygen saturation. During the work, a meta-analysis of available physiological data was performed and based on its result a hybrid model of forearm vascular tree was proposed. The model, in its structure, takes into account a classical nonlinear hydro-electric analogy in conjunction with light-tissue interaction. Several geometries of arm vascular tree obtained from magnetic resonance angiography (MRA) image were analyzed which allowed to proposed the structure of electrical analog network. Proposed model allows to simulate the behavior of forearm blood flow from the vascular tree mechanics point of view, as well as effects of the impact of cuff and vessel wall mechanics on the recorded photoplethysmographic signals. In particular, it allows to analyze the reaction and anatomical effects in small vessels and microcirculation caused by occlusive maneuver in selected techniques, what was of particular interest to authors and motivation to undertake research in this area. Preliminary studies using proposed model showed that inappropriate selection of occlusion maneuver parameters (e.g. occlusion time, cuff pressure etc.), cause dangerous turbulence of blood flow in the venous section of the vascular tree.

  16. States of low pulmonary blood flow can be detected non-invasively at the bedside measuring alveolar dead space.

    Science.gov (United States)

    Tusman, Gerardo; Suarez-Sipmann, Fernando; Paez, Gabriel; Alvarez, Jorge; Bohm, Stephan H

    2012-06-01

    We tested whether the ratio of alveolar dead space to alveolar tidal volume (VD(alv)/VT(alv)) can detect states of low pulmonary blood flow (PBF) in a non-invasive way. Fifteen patients undergoing cardiovascular surgeries with cardiopulmonary bypass (CPB) were studied. CPB is a technique that excludes the lungs from the general circulation. The weaning of CPB is a model that manipulates PBF in vivo because each time blood flow through the CPB decreases, expected PBF (ePBF) increases. Patients were liberated from CPB in steps of 20 % every 2' starting from 100 % CPB (very low ePBF) to 0 % CPB (100 % ePBF). During constant ventilation, volumetric capnograms were recorded and Bohr's dead space ratio (VD(Bohr)/VT), VD(alv)/VT(alv) and the ratio of airway dead space to tidal volume (VD(aw)/VT) were calculated. Before CPB, VD(Bohr)/VT was 0.36 ± 0.05, VD(aw)/VT 0.21 ± 0.04 and VD(alv)/VT(alv) 0.18 ± 0.06 (mean ± SD). During weaning from CPB, VD(aw)/VT remained unchanged while VD(Bohr)/VT and VD(alv)/VT(alv) decreased with increasing ePBF. At CPB of 80, 60, 40 and 20 % VD(Bohr)/VT was 0.64 ± 0.06, 0.55 ± 0.06, 0.47 ± 0.05 and 0.40 ± 0.04, respectively; p alveolar component of VD(Bohr)/VT increased in proportion to the deficit in lung perfusion.

  17. Non-invasive assessment of functionally relevant coronary artery stenoses with quantitative CT perfusion: preliminary clinical experiences

    Energy Technology Data Exchange (ETDEWEB)

    So, Aaron [Lawson Health Research Institute, Imaging Program, London, Ontario (Canada); Robarts Research Institute, Imaging Research Laboratories, London, Ontario (Canada); University of Western Ontario, Medical Biophysics, London, Ontario (Canada); Wisenberg, Gerald [Lawson Health Research Institute, Imaging Program, London, Ontario (Canada); University of Western Ontario, Medical Biophysics, London, Ontario (Canada); University of Western Ontario, Medical Imaging, London, Ontario (Canada); London Health Sciences Centre, Cardiology, London, Ontario (Canada); Islam, Ali; Amann, Justin; Romano, Walter [University of Western Ontario, Medical Imaging, London, Ontario (Canada); St. Joseph' s Health Care, Radiology, London, Ontario (Canada); Brown, James; Humen, Dennis; Jablonsky, George [London Health Sciences Centre, Cardiology, London, Ontario (Canada); Li, Jian-Ying; Hsieh, Jiang [GE Healthcare, CT Engineering, Waukesha, Wisconsin (United States); Lee, Ting-Yim [Lawson Health Research Institute, Imaging Program, London, Ontario (Canada); Robarts Research Institute, Imaging Research Laboratories, London, Ontario (Canada); University of Western Ontario, Medical Biophysics, London, Ontario (Canada); University of Western Ontario, Medical Imaging, London, Ontario (Canada)

    2012-01-15

    We developed a quantitative Dynamic Contrast-Enhanced CT (DCE-CT) technique for measuring Myocardial Perfusion Reserve (MPR) and Volume Reserve (MVR) and studied their relationship with coronary stenosis. Twenty-six patients with Coronary Artery Disease (CAD) were recruited. Degree of stenosis in each coronary artery was classified from catheter-based angiograms as Non-Stenosed (NS, angiographically normal or mildly irregular), Moderately Stenosed (MS, 50-80% reduction in luminal diameter), Severely Stenosed (SS, >80%) and SS with Collaterals (SSC). DCE-CT at rest and after dipyridamole infusion was performed using 64-slice CT. Mid-diastolic heart images were corrected for beam hardening and analyzed using proprietary software to calculate Myocardial Blood Flow (MBF, in mLmin{sup -1}100 g{sup -1}) and Blood Volume (MBV, in mL100 g{sup -1}) parametric maps. MPR and MVR in each coronary territory were calculated by dividing MBF and MBV after pharmacological stress by their respective baseline values. MPR and MVR in MS and SS territories were significantly lower than those of NS territories (p < 0.05 for all). Logistic regression analysis identified MPR MVR as the best predictor of {>=}50% coronary lesion than MPR or MVR alone. DCE-CT imaging with quantitative CT perfusion analysis could be useful for detecting coronary stenoses that are functionally significant. (orig.)

  18. Non invasive blood flow assessment in diabetic foot ulcer using laser speckle contrast imaging technique

    Science.gov (United States)

    Jayanthy, A. K.; Sujatha, N.; Reddy, M. Ramasubba; Narayanamoorthy, V. B.

    2014-03-01

    Measuring microcirculatory tissue blood perfusion is of interest for both clinicians and researchers in a wide range of applications and can provide essential information of the progress of treatment of certain diseases which causes either an increased or decreased blood flow. Diabetic ulcer associated with alterations in tissue blood flow is the most common cause of non-traumatic lower extremity amputations. A technique which can detect the onset of ulcer and provide essential information on the progress of the treatment of ulcer would be of great help to the clinicians. A noninvasive, noncontact and whole field laser speckle contrast imaging (LSCI) technique has been described in this paper which is used to assess the changes in blood flow in diabetic ulcer affected areas of the foot. The blood flow assessment at the wound site can provide critical information on the efficiency and progress of the treatment given to the diabetic ulcer subjects. The technique may also potentially fulfill a significant need in diabetic foot ulcer screening and management.

  19. A preliminary verification of the floating reference measurement method for non-invasive blood glucose sensing

    Science.gov (United States)

    Min, Xiaolin; Liu, Rong; Fu, Bo; Xu, Kexin

    2017-06-01

    In the non-invasive sensing of blood glucose by near-infrared diffuse reflectance spectroscopy, the spectrum is highly susceptible to the unstable and complicated background variations from the human body and the environment. In in vitro analyses, background variations are usually corrected by the spectrum of a standard reference sample that has similar optical properties to the analyte of interest. However, it is hard to find a standard sample for the in vivo measurement. Therefore, the floating reference measurement method is proposed to enable relative measurements in vivo, where the spectra under some special source-detector distance, defined as the floating reference position, are insensitive to the changes in glucose concentration due to the absorption effect and scattering effect. Because the diffuse reflectance signals at the floating reference positions only reflect the information on background variations during the measurement, they can be used as the internal reference. In this paper, the theoretical basis of the floating reference positions in a semi-infinite turbid medium was discussed based on the steady-state diffusion equation and its analytical solutions in a semi-infinite turbid medium (under the extrapolated boundary conditions). Then, Monte-Carlo (MC) simulations and in vitro experiments based on a custom-built continuous-moving spatially resolving double-fiber NIR measurement system, configured with two types of light source, a super luminescent diode (SLD) and a super-continuum laser, were carried out to verify the existence of the floating reference position in 5%, 10% and 20% Intralipid solutions. The results showed that the simulation values of the floating reference positions are close to the theoretical results, with a maximum deviation of approximately 0.3 mm in 1100-1320 nm. Great differences can be observed in 1340-1400 nm because the optical properties of Intralipid in this region don not satisfy the conditions of the steady

  20. Noninvasive methods of measuring bone blood perfusion

    OpenAIRE

    Dyke, J. P.; Aaron, R.K.

    2010-01-01

    Measurement of bone blood flow and perfusion characteristics in a noninvasive and serial manner would be advantageous in assessing revascularization after trauma and the possible risk of avascular necrosis. Many disease states, including osteoporosis, osteoarthritis, and bone neoplasms, result in disturbed bone perfusion. A causal link between bone perfusion and remodeling has shown its importance in sustained healing and regrowth following injury. Measurement of perfusion and permeability wi...

  1. The mean prehospital machine; accurate prehospital non-invasive blood pressure measurement in the critically ill patient.

    Science.gov (United States)

    Muecke, Sandy; Bersten, Andrew; Plummer, John

    2010-06-01

    Non-invasive blood pressure recordings may be inaccurate in the critically ill patient and measurement difficulties are intensified in the prehospital setting. This may adversely impact upon outcomes for many critically ill patients, particularly those with traumatic brain injury and/or lengthy prehospital times. This study aimed to validate a non-invasive, oscillometric, ambulatory blood pressure measuring device, the Oscar 2, Model 222 (SunTech Medical, Morrisville, USA) during the ambulance transport of critically ill patients. We have previously shown that mean arterial blood pressures observed by Intensive Care Unit nurses from a patient monitor can be considered interchangeable with reference intra-arterial integrated mean pressures. In the current study, we compared non-invasive device mean pressures to intra-arterial pressures observed by retrieval nurses from the patient monitor, during the ambulance transportation of critically ill patients. Device performance was required to fulfil the Association for the Advancement of Medical Instrumentation (AAMI) protocol requirements. Additionally, linear mixed effects analyses and Bland-Altman comparisons were undertaken. For 157 measurements recorded from 23 patients, when the Oscar 2 did not indicate a measurement was associated with a fault, the device fulfilled the AAMI protocol requirements, with a mean error of -1.1 mmHg (standard deviation 7.8 mmHg), 95% confidence intervals (linear mixed effects analysis) -2.9, 0.8; P = 0.26. Bland-Altman plots indicated uniform agreement across a wide range of blood pressures. Sixteen percent of recordings were associated with a patient, environment, or device generated fault. When the Oscar 2 does not indicate a fault has occurred, clinicians may be confident the mean pressure, within acceptable limits, is accurate, even during ambulance motion, administration of high doses of vasopressors and mechanical ventilation. The Oscar 2 appears to be an accurate and rugged out

  2. Non-invasive in Situ Simultaneous Measurement of Multi-parameter Mechanical Properties of Red Blood Cell Membrane

    Institute of Scientific and Technical Information of China (English)

    Jing LI; Yao-Xiong HUANG; Tao JI; Mei TU; Xuan MAO; Wen-Xin CHEN; Guang-Wei CHEN

    2005-01-01

    The purpose of this study was to develop a new dynamic image analyzing technique that will give us the ability to measure the viscoelastic parameters of individual living red blood cells non-invasively, in situ and in real time. With this technique, the bending modulus Kc, the shear elasticityμ and their ratio ε were measured under different temperatures, oxygen partial pressures and osmotic pressures. The results not only show the effects of external conditions on mechanical properties of cell membranes including deformability,flexibility, adhesive ability and plasticity, but also demonstrate that the technique can be used to measure cell membrane parameters continuously under several physiological and pathological conditions.

  3. Adaptive control with self-tuning for non-invasive beat-by-beat blood pressure measurement.

    Science.gov (United States)

    Nogawa, Masamichi; Ogawa, Mitsuhiro; Yamakoshi, Takehiro; Tanaka, Shinobu; Yamakoshi, Ken-ichi

    2011-01-01

    Up to now, we have successfully carried out the non-invasive beat-by-beat measurement of blood pressure (BP) in the root of finger, superficial temporal and radial artery based on the volume-compensation technique with reasonable accuracy. The present study concerns with improvement of control method for this beat-by-beat BP measurement. The measurement system mainly consists of a partial pressurization cuff with a pair of LED and photo-diode for the detection of arterial blood volume, and a digital self-tuning control method. Using healthy subjects, the performance and accuracy of this system were evaluated through comparison experiments with the system using a conventional empirically tuned PID controller. The significant differences of BP measured in finger artery were not showed in systolic (SBP), p=0.52, and diastolic BP (DBP), p=0.35. With the advantage of the adaptive control with self-tuning method, which can tune the control parameters without disturbing the control system, the application area of the non-invasive beat-by-beat measurement method will be broadened.

  4. Enrichment of Fetal Nucleated Red Blood Cells by Multi-core Magnetic Composite Particles for Non-invasive Prenatal Diagnosis

    Institute of Scientific and Technical Information of China (English)

    PAN Ying; ZHANG Ai-chen; WANG Qing; HUANG Wen-jun; QIAO Feng-li; LIU Yu-ping; ZHANG Yu-cheng; HAl De-yang; DU Ying-ting; WANG Wen-yue

    2012-01-01

    A novel kind of multi-core magnetic composite particles,the surfaces of which were respectively modified with goat-anti-mouse IgG and antitransferrin receptor(anti-CD71 ),was prepared.The fetal nucleated red blood cells(FNRBCs) in the peripheral blood of a gravida were rapidly and effectively enriched and separated by the modified multi-core magnetic composite particles in an external magnetic field.The obtained FNRBCs were used for the identification of the fetal sex by means of fluorescence in situ hybridization(FISH) technique.The results demonstrate that the multi-core magnetic composite particles meet the requirements for the enrichment and speration of FNRBCs with a low concentration and the accuracy of detetion for the diagnosis of fetal sex reached to 95%.Moreover,the obtained FNRBCs were applied to the non-invasive diagnosis of Down syndrome and chromosome 3p21 was detected.The above facts indicate that the novel multi-core magnetic composite particles-based method is simple,reliable and cost-effective and has opened up vast vistas for the potential application in clinic non-invasive prenatal diagnosis.

  5. Determination of the reference position in the near-infrared non-invasive blood glucose measurement in vivo

    Science.gov (United States)

    Han, Guang; Liu, Jin; Liu, Rong; Xu, Kexin

    2016-10-01

    Position-based reference measurement method is taken as one of the most promising method in non-invasive measurement of blood glucose based on spectroscopic methodology. Selecting an appropriate source-detector separation as the reference position is important for deducting the influence of background change and reducing the loss of useful signals. Our group proposed a special source-detector separation named floating-reference position where the signal contains only background change, that is to say, the signal at this source-detector separation is uncorrelated with glucose concentration. The existence of floating-reference position has been verified in a three layer skin by Monte Carlo simulation and in the in vitro experiment. But it is difficult to verify the existence of floating-reference position on the human body because the interference is more complex during in vivo experiment. Aiming at this situation, this paper studies the determination of the best reference position on human body by collecting signals at several source-detector separations on the palm and measuring the true blood glucose levels during oral glucose tolerance test (OGTT) experiments of 3 volunteers. Partial least square (PLS) calibration model is established between the signals at every source-detector separation and its corresponding blood glucose levels. The results shows that the correlation coefficient (R) between 1.32 mm to 1.88 mm is lowest and they can be used as reference for background correction. The signal of this special position is important for improving the accuracy of near-infrared non-invasive blood glucose measurement.

  6. Non-Invasive Monitoring of Temporal and Spatial Blood Flow during Bone Graft Healing Using Diffuse Correlation Spectroscopy.

    Directory of Open Access Journals (Sweden)

    Songfeng Han

    Full Text Available Vascular infiltration and associated alterations in microvascular blood flow are critical for complete bone graft healing. Therefore, real-time, longitudinal measurement of blood flow has the potential to successfully predict graft healing outcomes. Herein, we non-invasively measure longitudinal blood flow changes in bone autografts and allografts using diffuse correlation spectroscopy in a murine femoral segmental defect model. Blood flow was measured at several positions proximal and distal to the graft site before implantation and every week post-implantation for a total of 9 weeks (autograft n = 7 and allograft n = 10. Measurements of the ipsilateral leg with the graft were compared with those of the intact contralateral control leg. Both autografts and allografts exhibited an initial increase in blood flow followed by a gradual return to baseline levels. Blood flow elevation lasted up to 2 weeks in autografts, but this duration varied from 2 to 6 weeks in allografts depending on the spatial location of the measurement. Intact contralateral control leg blood flow remained at baseline levels throughout the 9 weeks in the autograft group; however, in the allograft group, blood flow followed a similar trend to the graft leg. Blood flow difference between the graft and contralateral legs (ΔrBF, a parameter defined to estimate graft-specific changes, was elevated at 1-2 weeks for the autograft group, and at 2-4 weeks for the allograft group at the proximal and the central locations. However, distal to the graft, the allograft group exhibited significantly greater ΔrBF than the autograft group at 3 weeks post-surgery (p < 0.05. These spatial and temporal differences in blood flow supports established trends of delayed healing in allografts versus autografts.

  7. Asynchronicity of facial blood perfusion in migraine.

    Directory of Open Access Journals (Sweden)

    Nina Zaproudina

    Full Text Available Asymmetrical changes in blood perfusion and asynchronous blood supply to head tissues likely contribute to migraine pathophysiology. Imaging was widely used in order to understand hemodynamic variations in migraine. However, mapping of blood pulsations in the face of migraineurs has not been performed so far. We used the Blood Pulsation Imaging (BPI technique, which was recently developed in our group, to establish whether 2D-imaging of blood pulsations parameters can reveal new biomarkers of migraine. BPI characteristics were measured in migraineurs during the attack-free interval and compared to healthy subjects with and without a family history of migraine. We found a novel phenomenon of transverse waves of facial blood perfusion in migraineurs in contrast to healthy subjects who showed synchronous blood delivery to both sides of the face. Moreover, the amplitude of blood pulsations was symmetrically distributed over the face of healthy subjects, but asymmetrically in migraineurs and subjects with a family history of migraine. In the migraine patients we found a remarkable correlation between the side of unilateral headache and the direction of the blood perfusion wave. Our data suggest that migraine is associated with lateralization of blood perfusion and asynchronous blood pulsations in the facial area, which could be due to essential dysfunction of the autonomic vascular control in the face. These findings may further enhance our understanding of migraine pathophysiology and suggest new easily available biomarkers of this pathology.

  8. Asynchronicity of facial blood perfusion in migraine.

    Science.gov (United States)

    Zaproudina, Nina; Teplov, Victor; Nippolainen, Ervin; Lipponen, Jukka A; Kamshilin, Alexei A; Närhi, Matti; Karjalainen, Pasi A; Giniatullin, Rashid

    2013-01-01

    Asymmetrical changes in blood perfusion and asynchronous blood supply to head tissues likely contribute to migraine pathophysiology. Imaging was widely used in order to understand hemodynamic variations in migraine. However, mapping of blood pulsations in the face of migraineurs has not been performed so far. We used the Blood Pulsation Imaging (BPI) technique, which was recently developed in our group, to establish whether 2D-imaging of blood pulsations parameters can reveal new biomarkers of migraine. BPI characteristics were measured in migraineurs during the attack-free interval and compared to healthy subjects with and without a family history of migraine. We found a novel phenomenon of transverse waves of facial blood perfusion in migraineurs in contrast to healthy subjects who showed synchronous blood delivery to both sides of the face. Moreover, the amplitude of blood pulsations was symmetrically distributed over the face of healthy subjects, but asymmetrically in migraineurs and subjects with a family history of migraine. In the migraine patients we found a remarkable correlation between the side of unilateral headache and the direction of the blood perfusion wave. Our data suggest that migraine is associated with lateralization of blood perfusion and asynchronous blood pulsations in the facial area, which could be due to essential dysfunction of the autonomic vascular control in the face. These findings may further enhance our understanding of migraine pathophysiology and suggest new easily available biomarkers of this pathology.

  9. Respiratory rate estimation from the oscillometric waveform obtained from a non-invasive cuff-based blood pressure device.

    Science.gov (United States)

    Pimentel, M A F; Santos, M D; Arteta, C; Domingos, J S; Maraci, M A; Clifford, G D

    2014-01-01

    The presence of respiratory activity in the electrocardiogram (ECG), the pulse oximeter's photoplethysmo-graphic and continuous arterial blood pressure signals is a well-documented phenomenon. In this paper, we demonstrate that such information is also present in the oscillometric signal acquired from automatic non-invasive blood pressure monitors, and may be used to estimate the vital sign respiratory rate (RR). We propose a novel method that combines the information from the two respiratory-induced variations (frequency and amplitude) via frequency analysis to both estimate RR and eliminate estimations considered to be unreliable because of poor signal quality. The method was evaluated using data acquired from 40 subjects containing ECG, respiration and blood pressure waveforms, the latter acquired using an in-house built blood pressure device that is able to connect to a mobile phone. Results demonstrated a good RR estimation accuracy of our method when compared to the reference values extracted from the reference respiration waveforms (mean absolute error of 2.69 breaths/min), which is comparable to existing methods in the literature that extract RR from other physiological signals. The proposed method has been implemented in Java on the Android device for use in an mHealth platform.

  10. Non-invasive estimation and control of inlet pressure in an implantable rotary blood pump for heart failure patients.

    Science.gov (United States)

    Alomari, A H; Savkin, A V; Ayre, P J; Lim, E; Mason, D G; Salamonsen, R F; Fraser, J F; Lovell, N H

    2011-08-01

    We propose a dynamical model for mean inlet pressure estimation in an implantable rotary blood pump during the diastolic period. Non-invasive measurements of pump impeller rotational speed (ω), motor power (P), and pulse width modulation signal acquired from the pump controller were used as inputs to the model. The model was validated over a wide range of speed ramp studies, including (i) healthy (C1), variations in (ii) heart contractility (C2); (iii) afterload (C2, C3, C4), and (iv) preload (C5, C6, C7). Linear regression analysis between estimated and extracted mean inlet pressure obtained from in vivo animal data (greyhound dogs, N = 3) resulted in a highly significant correlation coefficients (R(2) = 0.957, 0.961, 0.958, 0.963, 0.940, 0.946, and 0.959) and mean absolute errors of (e = 1.604, 2.688, 3.667, 3.990, 2.791, 3.215, and 3.225 mmHg) during C1, C2, C3, C4, C5, C6, and C7, respectively. The proposed model was also used to design a controller to regulate mean diastolic pump inlet pressure using non-invasively measured ω and P. In the presence of model uncertainty, the controller was able to track and settle to the desired input within a finite number of sampling periods and minimal error (0.92 mmHg). The model developed herein will play a crucial role in developing a robust control system of the pump that detects and thus avoids undesired pumping states by regulating the inlet pressure within a predefined physiologically realistic limit.

  11. Reliability and validity of non-invasive determined haemoglobin mass and blood volumes

    DEFF Research Database (Denmark)

    Fagoni, Nazzareno; Andersen, Andreas Breenfeldt; Oberholzer, Laura

    2017-01-01

    INTRODUCTION: The carbon monoxide (CO) rebreathing method used for the determination of haemoglobin mass (Hbmass ) is associated with blood sample analysis (in this study: Radiometer ABL800). As an alternative hereto the aim of the present study was to evaluate the use of a portable and non-invas...

  12. blood pressure influence of the the Invasive v. non-invasive ...

    African Journals Online (AJOL)

    1991-02-02

    Feb 2, 1991 ... invasive methods of measuring systemic blood pressure. However, there ..... was not possible due to the lack of a high speed recorder.) 3. A separate .... clinician needs to interpret the measurement in the light of the patient's ...

  13. Non-invasive prediction of blood lactate response to constant power outputs from incremental exercise tests.

    Science.gov (United States)

    Sullivan, C S; Casaburi, R; Storer, T W; Wasserman, K

    1995-01-01

    We determined the ability of gas exchange analyses during incremental exercise tests (IXT) to predict blood lactate levels associated with a range of constant power output cycle ergometer tests. Twenty-seven healthy young men performed duplicate IXT and four 15-min constant power output tests at intensities ranging from moderate to very severe, before and after a training program. End-exercise blood lactate levels were approximated from superficial venous samples obtained 60 s after each constant power output test. From IXT, the power outputs corresponding to peak oxygen uptake (Wmax) and lactic acidosis threshold (WLAT), were determined. We examined the ability of four measures of exercise intensity to predict blood lactate levels for power outputs above the LAT: (1) power output (W), (2) power difference (W-WLAT), (3) power fraction (W/Wmax) and (4) power difference to delta ratio [(W-WLAT)/(Wmax-WLAT)]. Correlation coefficients were r = 0.38, 0.69, 0.75, and 0.81, respectively. The best linear regression prediction equation was: lactate (mmol.l-1) = 12.2[(W-WLAT)/(Wmax-WLAT)] + 0.7 mmol.l-1. This relationship was not significantly affected by training, despite increased values of LAT and peak oxygen uptake. Normalizing exercise intensity to the range of power outputs between WLAT and Wmax provided an estimate of blood lactate response to constant power outputs with a standard error of the estimate of 1.66 mmol.l-1.

  14. [Non invasive prenatal diagnosis. Fetal nucleic acid analysis in maternal blood].

    Science.gov (United States)

    Sesarini, Carla; Argibay, Pablo; Otaño, Lucas

    2010-01-01

    Current prenatal diagnosis of monogeneic and chromosomal diseases, includes invasive procedures which carry a small but significant risk. For many years, analysis of fetal cells in maternal circulation has been studied, however it has failed its clinical use due to the scarcity of these cells and their persistance after delivery. For more than a decade, the presence of cell-free fetal DNA in maternal blood has been identified. These fetal DNA fragments would derive from the placenta and are not detected after delivery, making them a source of fetal material for carrying out diagnosis techniques using maternal blood. However, the vast majority of cell free DNA in maternal circulation is of maternal origin, with the fetal component contributing from 3% to 6% and rising towards term. Available methodologies do not allow separation of fetal from maternal cell free DNA, so current applications have been focused on the analysis of genes not present in the mother, such as Y chromosome sequences, or RHD gene in RhD-negative women, or paternal or de novo mutations. Also, the detection of cell-free fetal RNA in maternal blood offers the possibility of obtaining information regarding genetic expression profiles of embrionic tissues, and using genes expressed only at the feto-placental unit, controls for the presence of fetal material could be established, regardless of maternal genetic tissue. The present article describes the evidences regarding the passage of fetal nucleic acids to maternal circulation, its current prenatal diagnosis application and possible future perspectives.

  15. Regression approach to non-invasive determination of bilirubin in neonatal blood

    Science.gov (United States)

    Lysenko, S. A.; Kugeiko, M. M.

    2012-07-01

    A statistical ensemble of structural and biophysical parameters of neonatal skin was modeled based on experimental data. Diffuse scattering coefficients of the skin in the visible and infrared regions were calculated by applying a Monte-Carlo method to each realization of the ensemble. The potential accuracy of recovering the bilirubin concentration in dermis (which correlates closely with that in blood) was estimated from spatially resolved spectrometric measurements of diffuse scattering. The possibility to determine noninvasively the bilirubin concentration was shown by measurements of diffuse scattering at λ = 460, 500, and 660 nm at three source-detector separations under conditions of total variability of the skin biophysical parameters.

  16. Multivariate regression and discreminant calibration models for a novel optical non-invasive blood glucose measurement method named pulse glucometry.

    Science.gov (United States)

    Yamakoshi, Yasuhiro; Ogawa, Mitsuhiro; Yamakoshi, Takehiro; Tamura, Toshiyo; Yamakoshi, Ken-ichi

    2009-01-01

    A novel optical non-invasive in vivo blood glucose concentration (BGL) measurement technique, named "Pulse Glucometry", was combined with a kernel method; support vector machines. The total transmitted radiation intensity (I(lambda)) and the cardiac-related pulsatile changes superimposed on I(lambda) in human adult fingertips were measured over the wavelength range from 900 to 1700 nm using a very fast spectrophotometer, obtaining a differential optical density (DeltaOD(lambda)) related to the blood component in the finger tissues. Subsequently, a calibration model using paired data of a family of DeltaOD(lambda)s and the corresponding known BGLs was constructed with support vector machines (SVMs) regression instead of using calibration by a conventional primary component regression (PCR) and partial least squares regression (PLS). Secondly, SVM method was applied to make a nonlinear discriminant calibration model for "Pulse glucometry." Our results show that the regression calibration model based on the support vector machines can provide a good regression for the 101 paired data, in which the BGLs ranged from 89.0-219 mg/dl (4.94-12.2 mmol/l). The resultant regression was evaluated by the Clarke error grid analysis and all data points fell within the clinically acceptable regions (region A: 93%, region B: 7%). The discriminant calibration model using SVMs also provided a good result for classification (accuracy rate 84% in the best case).

  17. Non-invasive methods for absolute cerebral blood flow measurement using {sup 99m}Tc-ECD: a study in healthy volunteers

    Energy Technology Data Exchange (ETDEWEB)

    Van Laere, K.; Dierckx, R. [Div. of Nuclear Medicine, Ghent University Hospital (Belgium); Dumont, F. [Radiopharmacy Department, Faculty of Pharmaceutical Sciences, Ghent University, Ghent (Belgium); Koole, M. [Medical Image and Signal Processing Department (MEDISIP), Faculty of Applied Sciences, Ghent University, Ghent (Belgium)

    2001-07-01

    Radionuclide angiography with technetium-99m ethyl cysteinate dimer (ECD) allows non-invasive estimation of absolute cerebral blood flow (CBF), either by graphical Patlak-Gjedde analysis (PGA) or by spectral analysis (SA). Other methods estimate CBF by means of single-point arterial or venous sampling. The aim of this study was to evaluate radionuclide scanning and single-point venous sampling as potential clinical non- to minimally invasive methods for CBF determination in a large set of carefully screened healthy volunteers over the adult age range. Eighty-three carefully screened healthy volunteers (20-81 years, 43 males, 40 females) underwent planar radionuclide angiography with 925 MBq {sup 99m}Tc-ECD. After correction for camera dead-time loss, hemispheric CBF was calculated from brain perfusion indices (BPI): BPI{sup G} for PGA and BPI{sup S} for SA. Of the volunteers, 49 also underwent venous sampling 6 min post injection, from which the lipophilic octanol extraction fraction and hemispheric brain fractionation index (BFI) were determined. All datasets were correlated and evaluated as a function of age and gender. Intrasubject variability for the BPI measurements was assessed in 11 volunteers by repeat study within 2 weeks of the first acquisition. Graphical and spectral analysis BPIs were strongly correlated (R=0.846, P<0.00001). This correlation coefficient increased to R=0.903 for the 74 cases in which graphical analysis was not hampered by temporal tracer retention in cervicobrachial venous valves. The BFI was weakly correlated to both BPI indices (BPI{sup G}: R=0.34, P=0.02; BPI{sup S}: R=0.31, P=0.04). The right hemisphere showed significant asymmetry for BPI{sup S} (AI=2.7%{+-}4.3%, P<0.001), in correspondence with previous {sup 99m}Tc-ECD data. BPI{sup G}, BPI{sup S} and BFI were all inversely related to age, with an increased gradient after the age of 55 years, while there was no significant gender difference. The ratio of BPI{sup G} to BIP{sup S

  18. Relative indexes of cutaneous blood perfusion measured by real-time laser Doppler imaging (LDI) in healthy volunteers.

    Science.gov (United States)

    Seyed Jafari, S Morteza; Schawkat, Megir; Van De Ville, Dimitri; Shafighi, Maziar

    2014-07-01

    We used real-time LDI to study regional variations in microcirculatory perfusion in healthy candidates to establish a new methodology for global perfusion body mapping that is based on intra-individual perfusion index ratios. Our study included 74 (37 female) healthy volunteers aged between 22 and 30 years (mean 24.49). Imaging was performed using a recent microcirculation-imaging camera (EasyLDI) for different body regions of each volunteer. The perfusion values were reported in Arbitrary Perfusion Units (APU). The relative perfusion indexes for each candidate's body region were then obtained by normalization with the perfusion value of the forehead. Basic parameters such as weight, height, and blood pressure were also measured and analyzed. The highest mean perfusion value was reported in the forehead area (259.21APU). Mean perfusion in the measured parts of the body correlated positively with mean forehead value, while there was no significant correlation between forehead blood perfusion values and room temperature, BMI, systolic blood pressure and diastolic blood pressure (p=0.420, 0.623, 0.488, 0.099, respectively). Analysis of the data showed that perfusion indexes were not significantly different between male and female volunteers except for the ventral upper arm area (p=.001). LDI is a non-invasive, fast technique that opens several avenues for clinical applications. The mean perfusion indexes are useful in clinical practice for monitoring patients before and after surgical interventions. Perfusion values can be predicted for different body parts for patients only by taking the forehead perfusion value and using the perfusion index ratios to obtain expected normative perfusion values. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Non-invasive estimation of blood pressure using ultrasound contrast agents

    DEFF Research Database (Denmark)

    Andersen, Klaus Scheldrup; Jensen, Jørgen Arendt

    2009-01-01

    Local blood pressure measurements provide important information on the state of health of organs in the body and can be used to diagnose diseases in the heart, lungs, and kidneys. This paper presents an experimental setup for investigating the ambient pressure sensitivity of a contrast agent using...... measurement series at 485 kPa showed a sensitivity of 0.41 dB/kPa with a correlation coefficient of 0.89. Based on the measurements at 500 kPa, this acoustic driving pressure was concluded to be too high causing the bubbles to be destroyed. The pressure sensitivity for these two measurement series were 0...... diagnostic ultrasound. The setup resembles a realistic clinical setup utilizing a single array transducer for transmit and receive. The ambient pressure sensitivity of SonoVue (Bracco, Milano, Italy) was measured twice using two different acoustic driving pressures, which were selected based on a preliminary...

  20. Agreement between mathematically arterialised venous versus arterial blood gas values in patients undergoing non-invasive ventilation: a cohort study.

    Science.gov (United States)

    Kelly, Anne-Maree; Klim, Sharon; Rees, Stephen E

    2014-10-01

    Blood gas analysis is important for assessment of ventilatory function. Traditionally, arterial analysis has been used. A method for mathematically arterialising venous blood gas values has been developed. Our aim was to validate this method in patients undergoing non-invasive ventilation (NIV) in an emergency department (ED). This post hoc substudy of a prospective cohort study included adult patients undergoing NIV for acute respiratory compromise. When arterial blood gas analysis was required for clinical purposes, a venous sample was also drawn. Mathematically arterialised values were calculated independent of arterial values. Primary outcome of interest was agreement between mathematically arterialised venous and arterial values for pH and pCO2. Bland-Altman agreement plot analysis was used. Eighty sample-pairs (58 patients) were studied. Mean difference for arterial pH (actual-calculated) was 0.01 pH units (95% limits of agreement: -0.04, 0.06). Mean difference for pCO2 (actual-calculated) was -0.06 kPa (95% limits of agreement: -1.34, 1.22). For patients undergoing NIV in an ED, agreement between mathematically arterialised venous values and arterial values was close for pH but only moderate for pCO2. Depending on clinician tolerance for agreement, this method may be a clinically useful alternative to arterial blood gas analysis in the ED. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  1. Comparison of non-invasive blood pressure monitoring using modified arterial applanation tonometry with intra-arterial measurement.

    Science.gov (United States)

    Harju, Jarkko; Vehkaoja, Antti; Kumpulainen, Pekka; Campadello, Stefano; Lindroos, Ville; Yli-Hankala, Arvi; Oksala, Niku

    2017-01-19

    Intermittent non-invasive blood pressure measurement with tourniquets is slow, can cause nerve and skin damage, and interferes with other measurements. Invasive measurement cannot be safely used in all conditions. Modified arterial tonometry may be an alternative for fast and continuous measurement. Our aim was to compare arterial tonometry sensor (BPro(®)) with invasive blood pressure measurement to clarify whether it could be utilized in the postoperative setting. 28 patients who underwent elective surgery requiring arterial cannulation were analyzed. Patients were monitored post-operatively for 2 h with standard invasive monitoring and with a study device comprising an arterial tonometry sensor (BPro(®)) added with a three-dimensional accelerometer to investigate the potential impact of movement. Recordings were collected electronically. The results revealed inaccurate readings in method comparison between the devices based on recommendations by Association for the Advancement of Medical Instrumentation (AAMI). On a Bland-Altman plot, the bias and precision between these two methods was 19.8 ± 16.7 (Limits of agreement - 20.1 to 59.6) mmHg, Spearman correlation coefficient r = 0.61. For diastolic pressure, the difference was 4.8 ± 7.7 (LoA - 14.1 to 23.6) mmHg (r = 0.72), and for mean arterial pressure it was 11.18 ± 11.1 (LoA - 12.1 to 34.2) mmHg (r = 0.642). Our study revealed inaccurate agreement (AAMI) between the two methods when measuring systolic and mean blood pressures during post-operative care. The readings for diastolic pressures were inside the limits recommended by AAMI. Movement increased the failure rate significantly (p arterial tonometry is not an appropriate replacement for invasive blood pressure measurement in these patients.

  2. Non-invasive blood pressure measurement: values, problems and applicability in the common marmoset (Callithrix jacchus).

    Science.gov (United States)

    Mietsch, M; Einspanier, A

    2015-07-01

    The common marmoset (Callithrix jacchus, C. j.) is an established primate model in biomedical research and for human-related diseases. Monitoring of cardiovascular parameters including blood pressure (BP) is important for the health surveillance of these experimental animals and the quantification of diseases or pharmaceutical substances influencing BP. Measurement guidelines for C. j. do not exist yet; therefore, the present study was carried out to establish a practicable protocol based on recommendations of the American College of Veterinary Internal Medicine (ACVIM). Furthermore, BP data of 49 marmosets (13.8-202.4 months of age) were obtained via high-definition oscillometry to further knowledge of physiological parameters and gender-related differences in this primate. The thighs proved to be the most suitable measurement localization, since systolic values were less variable (left 4.03 ± 2.90%, right 5.96 ± 2.77%) compared with the tail (12.7 ± 6.96%). BP values were similar in the morning and in the afternoon (P > 0.05). Data were highly reproducible within and between several sessions on three consecutive days (P > 0.05) as well as over the course of 20 months (P > 0.05). Furthermore, the measurement time for females was significantly shorter than for males (5:14 ± 1:59 min versus 6:50 ± 1:58 min, P = 0.007). Measurement recommendations for the common marmoset were successfully established. Standardized values enabled a reliable comparison of BP parameters, e.g. for cardiovascular, toxicological or metabolic research.

  3. Overview of Five-Years of Experience Performing Non-Invasive Fetal Sex Assessment in Maternal Blood

    Directory of Open Access Journals (Sweden)

    Maria Jose Trujillo-Tiebas

    2013-05-01

    Full Text Available Since the discovery of the presence of fetal DNA in maternal blood, non-invasive fetal sex determination has been the test most widely translated into clinical practice. To date there is no agreement between the different laboratories performing such tests in relation to which is the best protocol. As a consequence there are almost as many protocols as laboratories offering the service, using different methodologies and thus obtaining different diagnostic accuracies. By the end of 2007, after a validation study performed in 316 maternal samples collected between the 5th and 12th week of gestation, the fetal sex determination was incorporated into clinical practice in our Service. The test is performed in the first trimester of pregnancy, and it is offered as part of the genetic counseling process for couples at risk of X-linked disorders. As a general rule and in order to avoid misdiagnosis, two samples at different gestational ages are tested per patient. The analysis is performed by the study of the SRY gene by RT-PCR. Two hundred and twenty six pregnancies have been tested so far in these 5 years. Neither false positives nor false negatives diagnoses have been registered, thus giving a diagnostic accuracy of 100%.

  4. DNA methylome profiling of maternal peripheral blood and placentas reveal potential fetal DNA markers for non-invasive prenatal testing.

    Science.gov (United States)

    Xiang, Yuqian; Zhang, Junyu; Li, Qiaoli; Zhou, Xinyao; Wang, Teng; Xu, Mingqing; Xia, Shihui; Xing, Qinghe; Wang, Lei; He, Lin; Zhao, Xinzhi

    2014-09-01

    Utilizing epigenetic (DNA methylation) differences to differentiate between maternal peripheral blood (PBL) and fetal (placental) DNA has been a promising strategy for non-invasive prenatal testing (NIPT). However, the differentially methylated regions (DMRs) have yet to be fully ascertained. In the present study, we performed genome-wide comparative methylome analysis between maternal PBL and placental DNA from pregnancies of first trimester by methylated DNA immunoprecipitation-sequencing (MeDIP-Seq) and Infinium HumanMethylation450 BeadChip assays. A total of 36 931 DMRs and 45 804 differentially methylated sites (DMSs) covering the whole genome, exclusive of the Y chromosome, were identified via MeDIP-Seq and Infinium 450k array, respectively, of which 3759 sites in 2188 regions were confirmed by both methods. Not only did we find the previously reported potential fetal DNA markers in our identified DMRs/DMSs but also we verified fully the identified DMRs/DMSs in the validation round by MassARRAY EpiTYPER. The screened potential fetal DNA markers may be used for NIPT on aneuploidies and other chromosomal diseases, such as cri du chat syndrome and velo-cardio-facial syndrome. In addition, these potential markers may have application in the early diagnosis of placental dysfunction, such as pre-eclampsia.

  5. Noninvasive quantification of myocardial perfusion heterogeneity by Markovian analysis in SPECT nuclear imaging; Quantification non invasive de l'heterogeneite de la perfusion du myocarde par analyse markovienne en imageries nucleaire SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Pons, G.

    2011-04-28

    Cardiovascular diseases are the leading cause of mortality worldwide, and third of these deaths are caused by coronary artery disease and rupture of vulnerable atherosclerotic plaques. The heterogeneous alteration of the coronary microcirculation is an early phenomenon associated with many cardiovascular risk factors that can strongly predict the subsequent development of coronary artery disease, and lead to the appearance of myocardial perfusion heterogeneity. Nuclear medicine allows the study of myocardial perfusion in clinical routine through scintigraphic scans performed after injection of a radioactive tracer of coronary blood flow. Analysis of scintigraphic perfusion images currently allows the detection of myocardial ischemia, but the ability of the technique to measure the perfusion heterogeneity in apparently normally perfused areas is unknown. The first part of this thesis focuses on a retrospective clinical study to determine the feasibility of myocardial perfusion heterogeneity quantification measured by Thallium-201 single photon emission computed tomography (SPECT) in diabetic patients compared with healthy subjects. The clinical study has demonstrated the ability of routine thallium-201 SPECT imaging to quantify greater myocardial perfusion heterogeneity in diabetic patients compared with normal subjects. The second part of this thesis tests the hypothesis that the myocardial perfusion heterogeneity could be quantified in small animal SPECT imaging by Thallium-201 and/or Technetium-99m-MIBI in an experimental study using two animal models of diabetes, and is correlated with histological changes. The lack of difference in myocardial perfusion heterogeneity between control and diabetic animals suggests that animal models are poorly suited, or that the technology currently available does not seem satisfactory to obtain similar results as the clinical study. (author)

  6. Blood purification and hemo- perfusion

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The method of blood purification is a new overlapping frontierdiscipline which develops quickly in recent years. It helps overcoming many serious and complicated diseases, even including some incurable illnesses.

  7. Noncontact blood perfusion mapping in clinical applications

    Science.gov (United States)

    Iakovlev, Dmitry; Dwyer, Vincent; Hu, Sijung; Silberschmidt, Vadim

    2016-04-01

    Non-contact imaging photoplethysmography (iPPG) to detect pulsatile blood microcirculation in tissue has been selected as a successor to low spatial resolution and slow scanning blood perfusion techniques currently employed by clinicians. The proposed iPPG system employs a novel illumination source constructed of multiple high power LEDs with narrow spectral emission, which are temporally modulated and synchronised with a high performance sCMOS sensor. To ensure spectrum stability and prevent thermal wavelength drift due to junction temperature variations, each LED features a custom-designed thermal management system to effectively dissipate generated heat and auto-adjust current flow. The use of a multi-wavelength approach has resulted in simultaneous microvascular perfusion monitoring at various tissue depths, which is an added benefit for specific clinical applications. A synchronous detection algorithm to extract weak photoplethysmographic pulse-waveforms demonstrated robustness and high efficiency when applied to even small regions of 5 mm2. The experimental results showed evidences that the proposed system could achieve noticeable accuracy in blood perfusion monitoring by creating complex amplitude and phase maps for the tissue under examination.

  8. Comparison of the non-invasive Nexfin® monitor with conventional methods for the measurement of arterial blood pressure in moderate risk orthopaedic surgery patients.

    Science.gov (United States)

    Balzer, Felix; Habicher, Marit; Sander, Michael; Sterr, Julian; Scholz, Stephanie; Feldheiser, Aarne; Müller, Michael; Perka, Carsten; Treskatsch, Sascha

    2016-08-01

    Continuous invasive arterial blood pressure (IBP) monitoring remains the gold standard for BP measurement, but traditional oscillometric non-invasive intermittent pressure (NIBP) measurement is used in most low-to-moderate risk procedures. This study compared non-invasive continuous arterial BP measurement using a Nexfin® monitor with NIBP and IBP monitors. This was a single-centre, prospective, pilot study in patients scheduled for elective orthopaedic surgery. Systolic BP, diastolic BP and mean arterial blood pressure (MAP) were measured by Nexfin®, IBP and NIBP at five intraoperative time-points. Pearson correlation coefficients, Bland-Altman plots and trending ability of Nexfin® measurements were used as criteria for success in the investigation of measurement reliability. A total of 20 patients were enrolled in the study. For MAP, there was a sufficient correlation between IBP/Nexfin® (Pearson = 0.75), which was better than the correlation between IBP/NIBP (Pearson = 0.70). Bland-Altman analysis of the data showed that compared with IBP, there was a higher percentage error for MAPNIBP (30%) compared with MAPNexfin® (27%). Nexfin® and NIBP underestimated systolic BP; NIBP also underestimated diastolic BP and MAP. Trending ability for MAPNexfin® and MAPNIBP were comparable to IBP. Non-invasive BP measurement with Nexfin® was comparable with IBP and tended to be more precise than NIBP. © The Author(s) 2016.

  9. Non-invasive submilligram level quantification of in vivo blood components with slitless high-sensitivity spectrometer and noncooled NIR detector

    Science.gov (United States)

    Kuribayashi, Ryosuke; Furukawa, Hiromitsu

    2015-03-01

    By using a "slit-less" Fourier-transform spectrometer, we demonstrate that cardiac-pulsation amplitude of absorbance can be extracted from 3.5-level absorbance unit (AU) spectra of a human fingertip with a resolution of blood components (water, HbO2, and lipids/proteins) in a fingertip are deduced in the sub-milligram order. The results indicate the capacity of the spectrometer for a portable non-invasive blood monitor as well as for a high-end analytic instrument.

  10. A systematic approach for the accurate non-invasive estimation of blood glucose utilizing a novel light-tissue interaction adaptive modelling scheme

    Energy Technology Data Exchange (ETDEWEB)

    Rybynok, V O; Kyriacou, P A [City University, London (United Kingdom)

    2007-10-15

    Diabetes is one of the biggest health challenges of the 21st century. The obesity epidemic, sedentary lifestyles and an ageing population mean prevalence of the condition is currently doubling every generation. Diabetes is associated with serious chronic ill health, disability and premature mortality. Long-term complications including heart disease, stroke, blindness, kidney disease and amputations, make the greatest contribution to the costs of diabetes care. Many of these long-term effects could be avoided with earlier, more effective monitoring and treatment. Currently, blood glucose can only be monitored through the use of invasive techniques. To date there is no widely accepted and readily available non-invasive monitoring technique to measure blood glucose despite the many attempts. This paper challenges one of the most difficult non-invasive monitoring techniques, that of blood glucose, and proposes a new novel approach that will enable the accurate, and calibration free estimation of glucose concentration in blood. This approach is based on spectroscopic techniques and a new adaptive modelling scheme. The theoretical implementation and the effectiveness of the adaptive modelling scheme for this application has been described and a detailed mathematical evaluation has been employed to prove that such a scheme has the capability of extracting accurately the concentration of glucose from a complex biological media.

  11. Improvement and development of non-invasive blood pressure measurement techniques%无创血压测量技术的改进与进展

    Institute of Scientific and Technical Information of China (English)

    郑理华; 窦建洪; 何兴华; 屠伟峰; 马铭俊; 吴昊

    2013-01-01

    This paper reviews the improvement and development of some general non-invasive blood pressure measurement(NBPM)techniques, e.g. korotkoff sound method, oscillometric method and double cuff method. The new practical techniques and methods at home and abroad and perspective of non-invasive continuous blood pressure measurement(NCBPM)have also been presented systematically in this article, such as arterial tonometry method, arterial volumn clamp method, pulse-wave velocity method, ultrasonic method and the application of wavelet analysis and fuzzy recognition. Finally, it's pointed out that NBPM, especially NCBPM, has a huge market demand. Pulse-wave velocity method can achieve real non-invasive continuous blood pressure measurement and thus has abroad application. Research progress of methods and theories of continuous non-invasive measurement of blood pressure will be a desired direction.%介绍数种常规的无创血压测量方法-柯氏音法、示波法和双袖带法及其改进.重点对国际上连续无创血压测量的新型实用技术、方法及前景进行较为详细的介绍,如动脉张力测量法、动脉容积钳制法、脉搏波速度测量法、超声测压法以及小波分析和模糊识别技术在血压信号处理中的应用等.指出无创血压测量技术,尤其是无创连续血压测量方法有着巨大的市场需求;脉搏波速度测量法能实现真正意义上的连续无创血压测量,因此具有广泛的应用前景,而采用新理论进行连续的无创血压测量将是该领域的目标和发展方向.

  12. [Application of wavelet transform on improving detecting precision of the non-invasive blood components measurement based on dynamic spectrum method].

    Science.gov (United States)

    Li, Gang; Men, Jian-Long; Sun, Zhao-Min; Wang, Hui-Quan; Lin, Ling; Tong, Ying; Zhang, Bao-Ju

    2011-02-01

    Time-varying noises in spectra collection process have influence on the prediction accuracy of quantitative calibration in the non-invasive blood components measurement which is based on dynamic spectrum (DS) method. By wavelet transform, we focused on the absorbance wave of fingertip transmission spectrum in pulse frequency band. Then we increased the signal to noise ratio of DS data, and improved the detecting precision of quantitative calibration. After carrying out spectrum data continuous acquisition of the same subject for 10 times, we used wavelet transform de-noising to increase the average correlation coefficient of DS data from 0.979 6 to 0.990 3. BP neural network was used to establish the calibration model of subjects' blood components concentration values against dynamic spectrum data of 110 volunteers. After wavelet transform de-noising, the correlation coefficient of prediction set increased from 0.677 4 to 0.846 8, and the average relative error was decreased from 15.8% to 5.3%. Experimental results showed that the introduction of wavelet transform can effectively remove the noise in DS data, improve the detecting precision, and accelerate the development of non-invasive blood components measurement based on DS method.

  13. Development of a Phantom Tissue for Blood Perfusion Measurements and Noninvasive Blood Perfusion Estimation in Living Tissue

    OpenAIRE

    Mudaliar, Ashvinikumar

    2007-01-01

    A convenient method for testing and calibrating surface perfusion sensors has been developed. A phantom tissue model is used to mimic the non-directional blood flow of tissue perfusion. A computational fluid dynamics (CFD) model was constructed in Fluent to design the phantom tissue and validate the experimental results. The phantom perfusion system was used with a perfusion sensor based on the clearance of thermal energy. A heat flux gage measures the heat flux response of tissue whe...

  14. Non-invasive diagnostic workup of patients with suspected stable angina by combined computed tomography coronary angiography and magnetic resonance perfusion imaging

    NARCIS (Netherlands)

    S.W.M. Kirschbaum (Sharon); K. Nieman (Koen); T. Springeling (Tirza); A.C. Weustink (Annick); S. Ramcharitar (Steve); C.A.G. van Mieghem (Carlos); A.G. Rossi (Adriano); E. Duckers (Eric); P.W.J.C. Serruys (Patrick); H. Boersma (Eric); P.J. de Feyter (Pim); R.J.M. van Geuns (Robert Jan)

    2011-01-01

    textabstractBackground: To evaluate additional adenosine magnetic resonance perfusion (MRP) imaging in the diagnostic workup of patients with suspected stable angina with computed tomography coronary angiography (CTCA) as first-line diagnostic modality. Methods and Results: Two hundred and thirty sy

  15. Compromised Cerebral Blood Flow(CBF) in Congestive Heart Failure (CHB): non-invasive quantification with {sup 99m}Tc-ECD radionuclide angiography

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae Seung; Kim, Jae Joong; Lim, Ki Chun; Lee, Hee Kyung; Moon, Dae Hyuk [Ulsan University College of Medicine, Seoul (Korea, Republic of)

    2002-07-01

    Recent reports revealed that cerebral metabolism in CHF was abnormally deranged and proposed as a potential marker of disease severity. Since deranged cerebral metabolism in CHF may result from compromised cerebral perfusion, quantification of CHF may be useful for accurate risk stratification of CHF. Therefore, we investigated whether CHF in patients with CHF is compromised and correlated with clinical parameters. Fifteen patients (M/F:11/5, 45{+-}9yr) with CHF (LVEF<40%) and 7 healthy controls (M/F:5/2, 41{+-}8yr) were prospectively studied. All patients underwent radionuclide angiography including cerebral hemispheres and aortic arch using {sup 99m}Tc-ECD. Global CBF was measured non-invasively by the application of Patlak graphical plot analysis. All patients were also evaluated using a standardized protocol that included echocardiography and clinical evaluation. Global CBF (40.3{+-}5.2 ml/min/100g) of the patients with CHF were significantly lower than those (49.7{+-}2.4 ml/min/100g) of controls (p<0.01). Global CBF were correlated with NYHA functional class (r=-0.617, p=0.43), but not correlated with other clinical parameters such as age (r=-0.463, p=0.082), duration (r=0.237, p>0.1), systolic BP (r=-0.063, p>0.5), LVEF (r=-0.13, p>0.1), LV dimension(r=0.139, p>0.5), and PV pressure gradients (r=0.072, p>0.5). Cerebral perfusion of the patients with CHF was compromised and not correlated with cardiopulmonary hemodynamic parameters.

  16. Time-resolved, single-cell analysis of induced and programmed cell death via non-invasive propidium iodide and counterstain perfusion

    Science.gov (United States)

    Krämer, Christina E. M.; Wiechert, Wolfgang; Kohlheyer, Dietrich

    2016-01-01

    Conventional propidium iodide (PI) staining requires the execution of multiple steps prior to analysis, potentially affecting assay results as well as cell vitality. In this study, this multistep analysis method has been transformed into a single-step, non-toxic, real-time method via live-cell imaging during perfusion with 0.1 μM PI inside a microfluidic cultivation device. Dynamic PI staining was an effective live/dead analytical tool and demonstrated consistent results for single-cell death initiated by direct or indirect triggers. Application of this method for the first time revealed the apparent antibiotic tolerance of wild-type Corynebacterium glutamicum cells, as indicated by the conversion of violet fluorogenic calcein acetoxymethyl ester (CvAM). Additional implementation of this method provided insight into the induced cell lysis of Escherichia coli cells expressing a lytic toxin-antitoxin module, providing evidence for non-lytic cell death and cell resistance to toxin production. Finally, our dynamic PI staining method distinguished necrotic-like and apoptotic-like cell death phenotypes in Saccharomyces cerevisiae among predisposed descendants of nutrient-deprived ancestor cells using PO-PRO-1 or green fluorogenic calcein acetoxymethyl ester (CgAM) as counterstains. The combination of single-cell cultivation, fluorescent time-lapse imaging, and PI perfusion facilitates spatiotemporally resolved observations that deliver new insights into the dynamics of cellular behaviour. PMID:27580964

  17. Invasive and non-invasive methods for cardiac output measurement

    Directory of Open Access Journals (Sweden)

    Lavdaniti M.

    2008-01-01

    Full Text Available The hemodynamic status monitoring of high-risk surgical patients and critically ill patients inIntensive Care Units is one of the main objectives of their therapeutic management. Cardiac output is one of the mostimportant parameters for cardiac function monitoring, providing an estimate of whole body perfusion oxygen deliveryand allowing for an understanding of the causes of high blood pressure. The purpose of the present review is thedescription of cardiac output measurement methods as presented in the international literature. The articles documentthat there are many methods of monitoring the hemodynamic status of patients, both invasive and non-invasive, themost popular of which is thermodilution. The invasive methods are the Fick method and thermodilution, whereasthe non-invasive methods are oeshophaegeal Doppler, transoesophageal echocardiography, lithium dilution, pulsecontour, partial CO2 rebreathing and thoracic electrical bioimpedance. All of them have their advantages and disadvantages,but thermodilution is the golden standard for critical patients, although it does entail many risks. The idealsystem for cardiac output monitoring would be non-invasive, easy to use, reliable and compatible in patients. A numberof research studies have been carried out in clinical care settings, by nurses as well as other health professionals, for thepurpose of finding a method of measurement that would have the least disadvantages. Nevertheless, the thermodilutiontechnique remains the most common approach in use today.

  18. The impact of continuous non-invasive arterial blood pressure monitoring on blood pressure stability during general anaesthesia in orthopaedic patients: A randomised trial.

    Science.gov (United States)

    Meidert, Agnes S; Nold, Johanna S; Hornung, Roman; Paulus, Alexander C; Zwißler, Bernhard; Czerner, Stephan

    2017-11-01

    In patients undergoing general anaesthesia, intraoperative hypotension occurs frequently and is associated with adverse outcomes such as postoperative acute kidney failure, myocardial infarction or stroke. A history of chronic hypertension renders patients more susceptible to a decrease in blood pressure (BP) after induction of general anaesthesia. As a patient's BP is generally monitored intermittently via an upper arm cuff, there may be a delay in the detection of hypotension by the anaesthetist. The current study investigates whether the presence of continuous BP monitoring leads to improved BP stability. Randomised, controlled and single-centre study. A total of 160 orthopaedic patients undergoing general anaesthesia with a history of chronic hypertension. The patients were randomised to either a study group (n = 77) that received continuous non-invasive BP monitoring in addition to oscillometric intermittent monitoring, or a control group (n = 83) whose BP was monitored intermittently only. The interval for oscillometric measurements in both groups was set to 3 min. After induction of general anaesthesia, oscillometric BP values of the two groups were compared for the first hour of the procedure. Anaesthetists were blinded to the purpose of the study. BP stability and hypotensive events. There was no difference in baseline BP between the groups. After adjustment for multiple testing, mean arterial BP in the study group was significantly higher than in the control group at 12 and 15 min. Mean ± SD for study and control group, respectively were: 12 min, 102 ± 24 vs. 90 ± 26 mmHg (P = 0.039) and 15 min, 102 ± 21 vs. 90 ± 23 mmHg (P = 0.023). Hypotensive readings below a mean pressure of 55 mmHg occurred more often in the control group (25 vs. 7, P = 0.047). Continuous monitoring contributes to BP stability in the studied population. NCT02519101.

  19. Utility of the microculture method for Leishmania detection in non-invasive samples obtained from a blood bank.

    Science.gov (United States)

    Ates, Sezen Canim; Bagirova, Malahat; Allahverdiyev, Adil M; Kocazeybek, Bekir; Kosan, Erdogan

    2013-10-01

    In recent years, the role of donor blood has taken an important place in epidemiology of Leishmaniasis. According to the WHO, the numbers of patients considered as symptomatic are only 5-20% of individuals with asymptomatic leishmaniasis. In this study for detection of Leishmania infection in donor blood samples, 343 samples from the Capa Red Crescent Blood Center were obtained and primarily analyzed by microscopic and serological methods. Subsequently, the traditional culture (NNN), Immuno-chromatographic test (ICT) and Polymerase Chain Reaction (PCR) methods were applied to 21 samples which of them were found positive with at least one method. Buffy coat (BC) samples from 343 blood donors were analyzed: 15 (4.3%) were positive by a microculture method (MCM); and 4 (1.1%) by smear. The sera of these 343 samples included 9 (2.6%) determined positive by ELISA and 7 (2%) positive by IFAT. Thus, 21 of (6.1%) the 343 subjects studied by smear, MCM, IFAT and ELISA techniques were identified as positive for leishmaniasis at least one of the techniques and the sensitivity assessed. According to our data, the sensitivity of the methods are identified as MCM (71%), smear (19%), IFAT (33%), ELISA (42%), NNN (4%), PCR (14%) and ICT (4%). Thus, with this study for the first time, the sensitivity of a MCM was examined in blood donors by comparing MCM with the methods used in the diagnosis of leishmaniasis. As a result, MCM was found the most sensitive method for detection of Leishmania parasites in samples obtained from a blood bank. In addition, the presence of Leishmania parasites was detected in donor bloods in Istanbul, a non-endemic region of Turkey, and these results is a vital importance for the health of blood recipients.

  20. [Coronary artery blood flow velocity non-invasively measured using a vessel-tracking pulsed Doppler system].

    Science.gov (United States)

    Tateishi, O; Aizawa, O; Okamura, T; Yoshida, T; Furuhata, H; Seo, Y; Iinuma, K; Shiki, E

    1988-09-01

    A newly-developed noninvasive method was used to measure left coronary blood flow during phantom experiments. Two techniques were used in which: (1) the sample position can always be set in a fluctuating vessel using a wall echo-tracking method with a phase-locked-loop, and (2) the Doppler reference signal was generated separately synchronous with the wall echo signal. These techniques were combined, using a commercially available pulsed Doppler apparatus (SSH-40B: Toshiba). Basic experiments were performed using a blood vessel phantom to verify the validity of these systems. Blood flow velocity in the fluctuating tube could be measured clearly using a vessel-tracking method. The blood flow velocity of the left anterior descending artery was measured in three normal subjects and in seven patients from the third intercostal space along the left sternal border. The velocity pattern was characterized by a crescendo-decrescendo shape in diastole. The peak velocity which appeared in diastole ranged from 19 to 69 cm/sec, with no difference by disease entity. However, in all cases, the blood flow velocity signals were marred by extraneous signals, making it impossible to measure blood flow velocity during systole. Further improvement of the system is mandatory in order to use this flowmeter clinically.

  1. Skin blood perfusion and oxygenation colour affect perceived human health.

    Directory of Open Access Journals (Sweden)

    Ian D Stephen

    Full Text Available Skin blood perfusion and oxygenation depends upon cardiovascular, hormonal and circulatory health in humans and provides socio-sexual signals of underlying physiology, dominance and reproductive status in some primates. We allowed participants to manipulate colour calibrated facial photographs along empirically-measured oxygenated and deoxygenated blood colour axes both separately and simultaneously, to optimise healthy appearance. Participants increased skin blood colour, particularly oxygenated, above basal levels to optimise healthy appearance. We show, therefore, that skin blood perfusion and oxygenation influence perceived health in a way that may be important to mate choice.

  2. Xeno- and auto-perfusion of rabbit kidney. Machine perfusion with blood at 37 degrees C

    DEFF Research Database (Denmark)

    Jørgensen, K A; Kemp, E; Barfort, P;

    1985-01-01

    Five rabbit kidneys were perfused with human blood and another five with their own blood in a re-circulating oxygenated system at 37 degrees C. The flow decreased to 2 ml/min. within 30 min. in all xenoperfusions, while none of the autoperfused had decreased to this level by 60 min. Endothelial...

  3. Support vector machines as multivariate calibration model for prediction of blood glucose concentration using a new non-invasive optical method named Pulse Glucometry.

    Science.gov (United States)

    Ogawa, Mitsuhiro; Yamakoshi, Yasuhiro; Satoh, Makoto; Nogawa, Masamichi; Yamakoshi, Takehiro; Tanaka, Shinobu; Rolfe, Peter; Tamura, Toshiyo; Yamakoshi, Ken-ichi

    2007-01-01

    A novel optical non-invasive in vivo blood glucose concentration (BGL) measurement technique, named "Pulse Glucometry", was combined with a kernel method; support vector machines. The total transmitted radiation intensity (I lambda) and the cardiac-related pulsatile changes superimposed on I lambda in human adult fingertips were measured over the wavelength range from 900 to 1700 nm using a very fast spectrophotometer, obtaining a differential optical density (delta OD lambda) related to the blood component in the finger tissues. Subsequently, a calibration model using paired data of a family of delta OD lambda s and the corresponding known BGLs was constructed with support vector machines regression instead of using calibration by a conventional partial least squares regression (PLS). Our results show that the calibration model based on the support vector machines can provide a good regression for the 183 paired data, in which the BGLs ranged from 89.0-219 mg/dl (4.94-12.2 mmol/l). The resultant regression was evaluated by the Clarke error grid analysis and all data points fell within the clinically acceptable regions (region A: 93%, region B: 7%).

  4. Non-invasive estimation of pulsatile flow and differential pressure in an implantable rotary blood pump for heart failure patients.

    Science.gov (United States)

    AlOmari, A H; Savkin, A V; Karantonis, D M; Lim, E; Lovell, N H

    2009-04-01

    We propose dynamical models for pulsatile flow and head estimation in an implantable rotary blood pump. Pulsatile flow and head data were obtained using a circulatory mock loop where fluid solutions with different values of viscosities were used as a blood analogue with varying haematocrit (HCT). Noninvasive measurements of power and pump speed were used with HCT values as inputs to the flow model while the estimated flow was used with the speed as inputs to a head estimation model. Linear regression analysis between estimated and measured flows obtained from a mock loop resulted in a highly significant correlation (R2=0.982) and a mean absolute error (e) of 0.323 L min(-1), while for head, R2=0.933 and e=7.682 mmHg were obtained. R2=0.849 and e=0.584 L min(-1) were obtained when the same model derived in the mock loop was used for flow estimation in ex vivo porcine data (N=6). Furthermore, in the steady state, the solution of the presented flow model can be described by a previously designed and verified static model. The models developed herein will play a vital role in developing a robust control system of the pump flow coping with changing physiological demands.

  5. Comparison of ASL and DCE MRI for the non-invasive measurement of renal blood flow: quantification and reproducibility

    Energy Technology Data Exchange (ETDEWEB)

    Cutajar, Marica; Hales, Patrick W.; Clark, Christopher A.; Gordon, Isky [UCL Institute of Child Health, Imaging and Biophysics Unit, London (United Kingdom); Thomas, David L. [UCL Institute of Neurology, Department of Brain Repair and Rehabilitation, London (United Kingdom); Banks, T. [Great Ormond Street Hospital, Department of Radiology, London (United Kingdom)

    2014-06-15

    To investigate the reproducibility of arterial spin labelling (ASL) and dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) and quantitatively compare these techniques for the measurement of renal blood flow (RBF). Sixteen healthy volunteers were examined on two different occasions. ASL was performed using a multi-TI FAIR labelling scheme with a segmented 3D-GRASE imaging module. DCE MRI was performed using a 3D-FLASH pulse sequence. A Bland-Altman analysis was used to assess repeatability of each technique, and determine the degree of correspondence between the two methods. The overall mean cortical renal blood flow (RBF) of the ASL group was 263 ± 41 ml min{sup -1} [100 ml tissue]{sup -1}, and using DCE MRI was 287 ± 70 ml min{sup -1} [100 ml tissue]{sup -1}. The group coefficient of variation (CV{sub g}) was 18 % for ASL and 28 % for DCE-MRI. Repeatability studies showed that ASL was more reproducible than DCE with CV{sub g}s of 16 % and 25 % for ASL and DCE respectively. Bland-Altman analysis comparing the two techniques showed a good agreement. The repeated measures analysis shows that the ASL technique has better reproducibility than DCE-MRI. Difference analysis shows no significant difference between the RBF values of the two techniques. (orig.)

  6. Cord Blood Karyotyping: A Safe and Non-Invasive Method for Postnatal Testing of Assisted Reproductive Technology Children

    Directory of Open Access Journals (Sweden)

    Shabnam Zarei Moradi

    2016-09-01

    Full Text Available Background: To verify the hypothesis that the incidence of chromosomal abnormalities increases in babies conceived by different assisted reproduction procedures. The availability of the umbilical cord blood encouraged us to study this hypothesis via this method. Materials and Methods: This is a descriptive study, umbilical cord blood samples of assisted reproductive technology (ART children were analyzed with standard cytogenetic techniques (G banding. Karyotyping was possible in 109 cases. Results: The number of abnormal cases was four (3.7%, among which, three cases (2.8% were inherited and only 1 case (0.9% was a de novo translocation. In total, the incidence of de novo chromosomal abnormalities was in the range observed in all live births in the general population (0.7-1%. Conclusion: No significant difference in the incidence of chromosomal abnormality was found between ART and naturally conceived babies. To date, several studies have examined the medical and developmental outcome of ART children and still have not reached a definite conclusion. Genetic counseling is recommended as an integral part of planning of treatment strategies for couples wishing to undergo ART.

  7. Non-invasive and transdermal measurement of blood uric acid level in human by electroporation and reverse iontophoresis

    Directory of Open Access Journals (Sweden)

    Chih-Kuei Lee

    2010-11-01

    Full Text Available Chih-Kuei Lee1, Congo Tak-Shing Ching2–4, Tai-Ping Sun2,3, Chun-Lang Tsai2, Wei Huang5, Hsin-Hung Huang6, Jen-Fu Kuo7, Li-Hang Lai6, Mei-Ya Chien8, Hsin-Hui Tseng9, Hui-Tzu Pan10, Shiow-Yuan Huang4, Hsiu-Li Shieh3, Wei-Hao Liu2, Chia-Ming Liu2, Hsin-Wei Huang21Hopkins Health Management Center, Puli Christian Hospital, Nantou, Taiwan, Republic of China; 2Graduate Institute of Biomedicine and Biomedical Technology, National Chi Nan University, Nantou, Taiwan, Republic of China; 3Department of Electrical Engineering, National Chi Nan University, Nantou, Taiwan, Republic of China; 4Department of Photonics and Communication Engineering, Asia University, Taichung, Taiwan, Republic of China; 5Division of Immunology and Rheumatology, Puli Christian Hospital, Nantou, Taiwan, Republic of China; 6Family Medical Department, Puli Christian Hospital, Nantou, Taiwan, Republic of China; 7Division of Endocrinology and Metabolism, Puli Christian Hospital, Nantou, Taiwan, Republic of China; 8Nutrition Department, Puli Christian Hospital, Nantou, Taiwan, Republic of China; 9Aboriginal Health Care, Puli Christian Hospital, Nantou, Taiwan, Republic of China; 10Department of Medical Research and Education, Puli Christian Hospital, Nantou, Taiwan, Republic of ChinaAbstract: The aim of this study was to find out the optimum combination of electroporation (EP and reverse iontophoresis (RI on noninvasive and transdermal determination of blood uric acid level in humans. EP is the use of high-voltage electric pulse to create nano-channels on the stratum corneum, temporarily and reversibly. RI is the use of small current to facilitate both charged and uncharged molecule transportation across the skin. It is believed that the combination of these two techniques has additional benefits on the molecules’ extraction across the human skin. In vitro studies using porcine skin and diffusion cell have indicated that the optimum mode for transdermal uric acid extraction is the

  8. Non-invasive cerebral blood volume measurement during seizures using multi-channel near infrared spectroscopic topography

    Science.gov (United States)

    Watanabe, Eiju; Maki, Atsushi; Kawaguchi, Fumio; Yamashita, Yuichi; Koizumi, Hideaki; Mayanagi, Yoshiaki

    2000-07-01

    Near infrared spectroscopic topography (NIRS) is widely recognized as a noninvasive method to measure the regional cerebral blood volume (rCBV) dynamics coupled with neuronal activities. We analyzed the rCBV change in the early phase of epileptic seizures in 12 consecutive patients with medically intractable epilepsy. Seizure was induced by bemegride injection. We used eight-channel NIRS in nine cases and 24 channel in three cases. In all of the cases, rCBV increased rapidly after the seizure onset on the focus side. The increased rCBV was observed for about 30 - 60 s. The NIRS method can be applied to monitor the rCBV change continuously during seizures. Therefore, this method may be combined with ictal SPECT as one of the most reliable noninvasive methods of focus diagnosis.

  9. 24 hr non-invasive ambulatory blood pressure and heart rate monitoring in Parkinson’s Disease

    Directory of Open Access Journals (Sweden)

    Eva eStübner

    2013-05-01

    Full Text Available Non-motor symptoms are now commonly recognized in Parkinson’s Disease (PD and can include dysautonomia. Impairment of cardiovascular autonomic function can occur at any stage of PD but is typically prevalent in advanced stages or related to (anti-parkinsonian drugs and can result in atypical blood pressure (BP readings and related symptoms such as orthostatic hypotension (OH and supine hypertension. OH is usually diagnosed with a head-up-tilt test (HUT or an (active standing test (also known as Schellong test in the laboratory, but 24 hour Ambulatory Blood Pressure Monitoring (ABPM in a home setting may have several advantages, such as providing an overview of symptoms in daily life alongside pathophysiology as well as assessment of treatment interventions. This, however, is only possible if ABPM is administrated correctly and an autonomic protocol (including a diary is followed. which will be discussed in this review. A 24hr ABPM does not only allow the detection of OH, if it is present, but also the assessment of cardiovascular autonomic dysfunction during and after various daily stimuli, such as postprandial and alcohol dependent hypotension, as well as exercise and drug induced hypotension. Furthermore, information about the circadian rhythm of BP and heart rate (HR can be obtained and establish whether or not a patient has a fall of BP at night (i.e. ‘dipper’ vs. non-‘dipper’. The information about nocturnal BP may also allow the investigation or detection of disorders such as sleep dysfunction, nocturnal movement disorders and obstructive sleep apnea, which are common in PD. Additionally, a 24hr ABPM should be conducted to examine the effectiveness of OH therapy. This review will outline the methodology of 24 hr ABPM in PD, summarize findings of such studies in PD and briefly consider common daily stimuli that might affect 24 Hr ABPM.

  10. The effect of blood pressure on non-invasive fractional flow reserve derived from coronary computed tomography angiography

    Energy Technology Data Exchange (ETDEWEB)

    Kurata, Akira [Ehime University Graduate School of Medicine, Department of Radiology, Toon, Ehime (Japan); Erasmus University Medical Center, Department of Radiology, Rotterdam (Netherlands); Coenen, Adriaan; Lubbers, Marisa M.; Nieman, Koen [Erasmus University Medical Center, Department of Radiology, Rotterdam (Netherlands); Erasmus University Medical Center, Departmenet of Cardiology, Rotterdam (Netherlands); Kido, Teruhito; Mochizuki, Teruhito [Ehime University Graduate School of Medicine, Department of Radiology, Toon, Ehime (Japan); Kido, Tomoyuki [Matsuyama Saiseikai Hospital, Department of Radiology, Matsuyama, Ehime (Japan); Yamashita, Natsumi [Clinical Research Center, National Hospital Organization Shikoku Cancer Center, Division of Clinical Biostatistics, Section of Cancer Prevention and Epidemiology, Matsuyama, Ehime (Japan); Watanabe, Kouki [Matsuyama Saiseikai Hospital, Department of Cardiology, Matsuyama, Ehime (Japan); Krestin, Gabriel P. [Erasmus University Medical Center, Department of Radiology, Rotterdam (Netherlands)

    2017-04-15

    The aim of this study is to assess the effect of blood pressure (BP) on coronary computed tomography angiography (CTA) derived computational fractional flow reserve (CTA-FFR). Twenty-one patients who underwent coronary CTA and invasive FFR were retrospectively identified. Ischemia was defined as invasive FFR ≤0.80. Using a work-in-progress computational fluid dynamics algorithm, CTA-FFR was computed with BP measured before CTA, and simulated BPs of 60/50, 90/60, 110/70, 130/80, 150/90, and 180/100 mmHg respectively. Correlation between CTA-FFR and invasive FFR was assessed using Pearson test. The repeated measuring test was used for multiple comparisons of CTA-FFR values by simulated BP inputs. Twenty-nine vessels (14 with invasive FFR ≤0.80) were assessed. The average CTA-FFR for measured BP (134 ± 20/73 ± 12 mmHg) was 0.77 ± 0.12. Correlation between CTA-FFR by measured BP and invasive FFR was good (r = 0.735, P < 0.001). For simulated BPs of 60/50, 90/60, 110/70, 130/80, 150/90, and 180/100 mmHg, the CTA-FFR increased: 0.69 ± 0.13, 0.73 ± 0.12, 0.75 ± 0.12, 0.77 ± 0.11, 0.79 ± 0.11, and 0.81 ± 0.10 respectively (P < 0.05). Measurement of the BP just before CTA is preferred for accurate CTA-FFR simulation. BP variations in the common range slightly affect CTA-FFR. However, inaccurate BP assumptions differing from the patient-specific BP could cause misinterpretation of borderline significant lesions. (orig.)

  11. Assessment of differential pulmonary blood flow using perfusion magnetic resonance imaging: comparison with radionuclide perfusion scintigraphy.

    Science.gov (United States)

    Molinari, Francesco; Fink, Christian; Risse, Frank; Tuengerthal, Siegfried; Bonomo, Lorenzo; Kauczor, Hans-Ulrich

    2006-08-01

    We sought to assess the agreement between lung perfusion ratios calculated from pulmonary perfusion magnetic resonance imaging (MRI) and those calculated from radionuclide (RN) perfusion scintigraphy. A retrospective analysis of MR and RN perfusion scans was conducted in 23 patients (mean age, 60 +/- 14 years) with different lung diseases (lung cancer = 15, chronic obstructive pulmonary disease = 4, cystic fibrosis = 2, and mesothelioma = 2). Pulmonary perfusion was assessed by a time-resolved contrast-enhanced 3D gradient-echo pulse sequence using parallel imaging and view sharing (TR = 1.9 milliseconds; TE = 0.8 milliseconds; parallel imaging acceleration factor = 2; partition thickness = 4 mm; matrix = 256 x 96; in-plane spatial resolution = 1.87 x 3.75 mm; scan time for each 3D dataset = 1.5 seconds), using gadolinium-based contrast agents (injection flow rate = 5 mL/s, dose = 0.1 mmol/kg of body weight). The peak concentration (PC) of the contrast agent bolus, the pulmonary blood flow (PBF), and blood volume (PBV) were computed from the signal-time curves of the lung. Left-to-right ratios of pulmonary perfusion were calculated from the MR parameters and RN counts. The agreement between these ratios was assessed for side prevalence (sign test) and quantitatively (Deming-regression). MR and RN ratios agreed on side prevalence in 21 patients (91%) with PC, in 20 (87%) with PBF, and in 17 (74%) with PBV. The MR estimations of left-to-right perfusion ratios correlated significantly with those of RN perfusion scans (P lung. Further studies in a larger group of patients are required to fully confirm the clinical suitability of this imaging method.

  12. Non-invasive delivery of stealth, brain-penetrating nanoparticles across the blood-brain barrier using MRI-guided focused ultrasound.

    Science.gov (United States)

    Nance, Elizabeth; Timbie, Kelsie; Miller, G Wilson; Song, Ji; Louttit, Cameron; Klibanov, Alexander L; Shih, Ting-Yu; Swaminathan, Ganesh; Tamargo, Rafael J; Woodworth, Graeme F; Hanes, Justin; Price, Richard J

    2014-09-10

    The blood-brain barrier (BBB) presents a significant obstacle for the treatment of many central nervous system (CNS) disorders, including invasive brain tumors, Alzheimer's, Parkinson's and stroke. Therapeutics must be capable of bypassing the BBB and also penetrate the brain parenchyma to achieve a desired effect within the brain. In this study, we test the unique combination of a non-invasive approach to BBB permeabilization with a therapeutically relevant polymeric nanoparticle platform capable of rapidly penetrating within the brain microenvironment. MR-guided focused ultrasound (FUS) with intravascular microbubbles (MBs) is able to locally and reversibly disrupt the BBB with submillimeter spatial accuracy. Densely poly(ethylene-co-glycol) (PEG) coated, brain-penetrating nanoparticles (BPNs) are long-circulating and diffuse 10-fold slower in normal rat brain tissue compared to diffusion in water. Following intravenous administration of model and biodegradable BPNs in normal healthy rats, we demonstrate safe, pressure-dependent delivery of 60nm BPNs to the brain parenchyma in regions where the BBB is disrupted by FUS and MBs. Delivery of BPNs with MR-guided FUS has the potential to improve efficacy of treatments for many CNS diseases, while reducing systemic side effects by providing sustained, well-dispersed drug delivery into select regions of the brain.

  13. Comparative Study of Invasive Blood Pressure and Non-invasive Blood Pressure in General Anesthesia%全身麻醉患者无创血压与有创血压的对比研究

    Institute of Scientific and Technical Information of China (English)

    徐鑫; 吴廷丽; 马正良; 顾小萍

    2015-01-01

    Objective To investigate the differences of invasive blood pressure( IBP) and non-invasive blood pressure( NIBP) in general anesthesia.Methods Eighty-two patients undergoing general anesthesia were divided into four groups depending on invasive systolic blood pressure (ISBP):group A, ISBP≤90mmHg;group B,ISBP 90-120 mmHg;group C, ISBP 120-150mmHg;group D, ISBP>150mmHg.Non-invasive blood pressure and arterial blood pressure was monitored at the same time.Bilateral NIBP and IBP val-ues were compared by paired t-test and linear correlation analysis.Results There was no significant difference between bilateral NIBP of four groups.Invasive systolic blood pressure was lower than bilateral non-invasive systolic blood pressure in group A (P0.05).Arterial diastolic blood pressure was sig-nificantly lower than bilateral non-invasive diastolic blood pressure in group B and C.There was significant correlation between arterial systolic blood pressure and bilateral non-invasive systolic blood pressure (r=0.940,P<0.01).There was significant correlation be-tween arterial diastolic blood pressure and bilateral non-invasive diastolic blood pressure (r=0.925,P<0.01).Conclusion There was significant difference and correlation between arterial blood pressure and non-invasive blood pressure.Arterial blood pressure can be estimated by non-invasive blood pressure in certain blood pressure range.%目的:探讨全身麻醉患者双侧肱动脉无创血压( NIBP)与桡动脉有创动脉压( IBP)的关系。方法于全身麻醉下进行手术的患者82例,麻醉诱导前后及术中同步测量双侧无创血压及有创血压,根据有创收缩压值( ISBP)大小分为A组( ISBP≤90mmHg)、B组(90mmHg<ISBP≤120mmHg)、C组(120mmHg<ISBP≤150mmHg)和D组(ISBP>150mmHg)。对各组数值进行差异分析,并对有创血压和无创血压值做线性相关分析。结果4组患者双侧无创血压无统计学差异(P>0.05);A组有创

  14. A non-invasive miniaturized-wireless laser-Doppler fiber optic sensor for understanding distal fingertip injuries in astronauts

    Science.gov (United States)

    Ansari, Rafat R.; Jones, Jeffrey A.; Pollonini, Luca; Rodriguez, Mikael; Opperman, Roedolph; Hochstein, Jason

    2009-02-01

    During extra-vehicular activities (EVAs) or space walks astronauts over use their fingertips under pressure inside the confined spaces of gloves/space-suite. The repetitive hand motion is a probable cause for discomfort and injuries to the finger-tips. We describe a new wireless fiber-optic probe that can be integrated inside the astronaut glove for non-invasive blood perfusion measurements in distal finger tips. In this preliminary study, we present blood perfusion measurements while performing hand-grip exercises simulating the use of space tools.

  15. Laser Doppler perfusion monitoring and imaging of blood microcirculation

    Science.gov (United States)

    Nilsson, Gert E.; Wardell, Karin

    1994-07-01

    Laser Doppler perfusion monitoring is a method of assessing tissue perfusion based on measurements performed using Doppler broadening of monochromatic light scattered in moving blood cells. Ever since laser Doppler perfusion monitors became available about 15 years ago they have been used in numerous applications in both clinical and laboratory settings. The high spatial resolution has in practice manifested itself as one of the main limitations of the method. The reason for this is the difficulty in attaining reproducible values at successive measurement sites because most skin tissue possesses a substantial variation in blood flow even at adjacent measurement sites. In order to overcome this difficulty the laser Doppler perfusion imager was developed. In this camera-like device, the laser beam successively scans the tissue and the Doppler components of the backscattered light are detected by a remote photodiode. After a scanning procedure is complete, a color-coded perfusion map showing the spatial variation of skin blood flow is displayed on a monitor. The operating principle and early applications of this emerging technology are addressed in further detail.

  16. Evaluation of Influence of Acupuncture and Electro-Acupuncture for Blood Perfusion of Stomach by Laser Doppler Blood Perfusion Imaging

    OpenAIRE

    Zhang Dong; Li Shun-Yue; Wang Shu-You; Ma Hui-Min

    2011-01-01

    The objective of this study is to observe effects of acupuncture and electro-acupuncture (EA) on blood perfusion in the stomach, and probe into the application of laser Doppler blood perfusion imaging technique in the study of the effect of acupuncture and moxibustion on the entrails. In the acupuncture group of 20 rats, acupuncture was given at “Zusanli” (ST 36) and in EA group of 18 rats, EA was applied at “Zusanli” (ST 36), with 18 rats without acupuncture used as control group. Changes of...

  17. Short term non-invasive ventilation post-surgery improves arterial blood-gases in obese subjects compared to supplemental oxygen delivery - a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Zoremba Norbert

    2011-05-01

    Full Text Available Abstract Background In the immediate postoperative period, obese patients are more likely to exhibit hypoxaemia due to atelectasis and impaired respiratory mechanics, changes which can be attenuated by non-invasive ventilation (NIV. The aim of the study was to evaluate the duration of any effects of early initiation of short term pressure support NIV vs. traditional oxygen delivery via venturi mask in obese patients during their stay in the PACU. Methods After ethics committee approval and informed consent, we prospectively studied 60 obese patients (BMI 30-45 undergoing minor peripheral surgery. Half were randomly assigned to receive short term NIV during their PACU stay, while the others received routine treatment (supplemental oxygen via venturi mask. Premedication, general anaesthesia and respiratory settings were standardized. We measured arterial oxygen saturation by pulse oximetry and blood gas analysis on air breathing. Inspiratory and expiratory lung function was measured preoperatively (baseline and at 10 min, 1 h, 2 h, 6 h and 24 h after extubation, with the patient supine, in a 30 degrees head-up position. The two groups were compared using repeated-measure analysis of variance (ANOVA and t-test analysis. Statistical significance was considered to be P Results There were no differences at the first assessment. During the PACU stay, pulmonary function in the NIV group was significantly better than in the controls (p Conclusion Early initiation of short term NIV during in the PACU promotes more rapid recovery of postoperative lung function and oxygenation in the obese. The effect lasted 24 hours after discontinuation of NIV. Patient selection is necessary in order to establish clinically relevant improvements. Trial Registration# DRKS00000751; http://www.germanctr.de

  18. Analysis of peripheral blood dendritic cells as a non-invasive tool in the follow-up of patients with chronic hepatitis C.

    Science.gov (United States)

    Crosignani, Andrea; Riva, Antonio; Della Bella, Silvia

    2016-01-28

    Hepatitis C virus (HCV) has a high propensity to establish chronic infections. Failure of HCV-infected individuals to activate effective antiviral immune responses is at least in part related to HCV-induced impairment of dendritic cells (DCs) that play a central role in activating T cell responses. Although the impact of HCV on DC phenotype and function is likely to be more prominent in the liver, major HCV-induced alterations are detectable in peripheral blood DCs (pbDCs) that represent the most accessible source of DCs. These alterations include numerical reduction, impaired production of inflammatory cytokines and increased production of immunosuppressive IL10. These changes in DCs are relevant to our understanding the immune mechanisms underlying the propensity of HCV to establish persistent infection. Importantly, the non-invasive accessibility of pbDCs renders the analysis of these cells a convenient procedure that can be serially repeated in patient follow-up. Accordingly, the study of pbDCs in HCV-infected patients during conventional treatment with pegylated interferon and ribavirin indicated that restoration of normal plasmacytoid DC count may represent an additional mechanism contributing to the efficacy of the dual therapy. It also identified the pre-treatment levels of plasmacytoid DCs and IL10 as putative predictors of response to therapy. Treatment of chronic HCV infection is changing, as new generation direct-acting antiviral agents will soon be available for use in interferon-free therapeutic strategies. The phenotypic and functional analysis of pbDCs in this novel therapeutic setting will provide a valuable tool for investigating mechanisms underlying treatment efficacy and for identifying predictors of treatment response.

  19. Mucosal blood flow measurements using laser Doppler perfusion monitoring

    Institute of Scientific and Technical Information of China (English)

    Dag Arne Lihaug Hoff; Hans Gregersen; Jan Gunnar Hatlebakk

    2009-01-01

    Perfusion of individual tissues is a basic physiological process that is necessary to sustain oxygenation and nutrition at a cellular level. Ischemia, or the insufficiency of perfusion, is a common mechanism for tissue death or degeneration, and at a lower threshold, a mechanism for the generation of sensory signalling including pain. It is of considerable interest to study perfusion of peripheral abdominal tissues in a variety of circumstances. Microvascular disease of the abdominal organs has been implicated in the pathogenesis of a variety of disorders, including peptic ulcer disease, inflammatory bowel disease and chest pain. The basic principle of laser Doppler perfusion monitoring (LDPM) is to analyze changes in the spectrum of light reflected from tissues as a response to a beam of monochromatic laser light emitted. It reflects the total local microcirculatory blood perfusion, including perfusion in capillaries, arterioles, venules and shunts. During the last 20-25 years, numerous studies have been performed in different parts of the gastrointestinal (GI) tract using LDPM. In recent years we have developed a multi-modal catheter device which includes a laser Doppler probe, with the intent primarily to investigate patients suffering from functional chest pain of presumed oesophageal origin. Preliminary studies show the feasibility of incorporating LDPM into such catheters for performing physiological studies in the GI tract. LDPM has emerged as a research and clinical tool in preference to other methods; but, it is important to be aware of its limitations and account for them when reporting results.

  20. Accuracy Evaluation of Non-invasive Blood Pressure Monitor in Blood Pressure Measurement of Patients with Atrial Fibrillation%无创血压监护仪在心房纤颤病人血压测量中的准确性评价

    Institute of Scientific and Technical Information of China (English)

    胡文志; 周海波

    2014-01-01

    目的:探讨无创血压监护仪在心房纤颤病人血压测量中的准确性。方法对60例心房纤颤病人分别采用无创血压监护仪和汞柱台式血压计进行血压监测,对比其测量结果。结果无创血压监护仪和汞柱台式血压计血压测量结果比较,收缩压无显著差异(P>0.05),而舒张压有显著差异(P<0.05)。结论无创血压监护仪在心房纤颤病人血压测量中的准确性较差,值得临床注意。%Objective To investigate the accuracy of non-invasive blood pressure monitor in blood pressure measurement of patients with atrial fibrillation. Methods The blood pressure of 60 patients with atrial fibrillation was measured by using non-invasive blood pressure monitor and mercury sphygmomanometer, respectively. Then the measuring results of blood pressure of non-invasive blood pressure monitor were compared with those of mercury sphygmomanometer. Results There was no signiifcant difference between the measuring results of blood pressure of non-invasive blood pressure and those of mercury sphygmomanometer on systolic pressure (P>0.05) while there were signiifcant differences between the measuring results of blood pressure of non-invasive blood pressure and those of mercury sphygmomanometer on diastolic pressure (P<0.05). Conclusion It is inaccurate to measure the blood pressure of patients with atrial ifbrillation by using non-invasive blood pressure monitor, which should be paid attention to in clinic.

  1. Assessment of Blood Flow in Hepatocellular Carcinoma: Correlations of Computed Tomography Perfusion Imaging and Circulating Angiogenic Factors

    Directory of Open Access Journals (Sweden)

    Chen-Pin Chou

    2013-08-01

    Full Text Available Hepatocellular carcinoma (HCC is a highly vascular tumor through the process of angiogenesis. To evaluate more non-invasive techniques for assessment of blood flow (BF in HCC, this study examined the relationships between BF of HCC measured by computer tomography (CT perfusion imaging and four circulating angiogenic factors in HCC patients. Interleukin 6 (IL-6, interleukin 8 (IL-8, vascular endothelial growth factor (VEGF, and platelet derived growth factor (PDGF in plasma were measured using Bio-Plex multiplex immunoassay in 21 HCC patients and eight healthy controls. Circulating IL-6, IL-8 and VEGF showed higher concentrations in HCC patients than in controls (p < 0.05, and predicted HCC occurrence better than chance (p < 0.01. Twenty-one patients with HCC received 21-phase liver imaging using a 64-slice CT. Total BF, arterial BF, portal BF, arterial fraction (arterial BF/total BF of the HCC and surrounding liver parenchyma, and HCC-parenchyma ratio were measured using a dual-vessel model. After analyzing the correlations between BF in HCC and four circulating angiogenic factors, we found that the HCC-parenchyma ratio of arterial BF showed a significantly positive correlation with the level of circulating IL-8 (p < 0.05. This circulating biomarker, IL-8, provides a non-invasive tool for assessment of BF in HCC.

  2. PET-measured heterogeneity in longitudinal myocardial blood flow in response to sympathetic and pharmacologic stress as a non-invasive probe of epicardial vasomotor dysfunction

    Energy Technology Data Exchange (ETDEWEB)

    Schindler, Thomas H.; Facta, Alvaro D.; Prior, John O.; Campisi, Roxana; Inubushi, Masayuki; Kreissl, Michael C.; Zhang, Xiao-Li; Sayre, James; Dahlbom, Magnus; Schelbert, Heinrich R. [University of California at Los Angeles, Department of Molecular and Medical Pharmacology, Los Angeles, CA (United States)

    2006-10-15

    We investigated whether a myocardial perfusion gradient during pharmacologically induced hyperemia also occurred during sympathetic stimulation with cold pressor testing (CPT), which commonly induces a paradoxical coronary vasoconstriction in individuals with coronary risk factors. Myocardial blood flow (MBF) was measured in absolute units (ml/g/min) with {sup 13}N-ammonia and PET at rest, during CPT, and during pharmacologic vasodilation in 59 participants with coronary risk factors (''at risk'') and in 43 healthy individuals (controls). MBF was assessed globally as mean MBF, and in the mid and mid-distal myocardium of the left ventricle (LV). A decrease in MBF from mid to mid-distal LV myocardium was defined as MBF difference indicative of a perfusion gradient. The change in mean MBF to CPT ({delta}MBF) in the at-risk group was significantly reduced compared with controls (0.05{+-}0.19 vs 0.31{+-}0.20 ml/g/min, p<0.0001), whereas mean MBF during pharmacologic vasodilation in the at-risk group tended to be lower than in controls (1.72{+-}0.71 vs 2.00{+-}0.64 ml/g/min, p=NS). Absolute MBFs during CPT and pharmacologic vasodilation were significantly lower in the mid-distal than in the mid LV myocardium, resulting in a significant MBF difference in the at-risk group (0.15{+-}0.06 and 0.27{+-}0.12 ml/g/min, p<0.0001) that was not observed in controls (0.007{+-}0.05 and 0.014{+-}0.10 ml/g/min, p=NS). In the at-risk group there was a significant correlation between the difference of mid to mid-distal MBF during CPT and that during pharmacologic vasodilation (r=0.43, p<0.004), suggesting functional alterations of epicardial vessels as the predominant cause for the observed MBF difference. The relative decrease in MBF from the mid to the mid-distal left-ventricular myocardium suggests an intracoronary pressure decline during CPT and pharmacologic vasodilation, which is likely to reflect an impairment of flow-mediated epicardial vasomotor function

  3. Renal perfusion with venous blood extends the permissible suprarenal clamp time in abdominal aortic surgery

    National Research Council Canada - National Science Library

    Pichlmaier, Maximilian; Hoy, Ludwig; Wilhelmi, Mathias; Khaladj, Nawid; Haverich, Axel; Teebken, Omke E

    2008-01-01

    ... suprarenal clamping for aortic reconstructive surgery. Renal perfusion was achieved using a roller pump supplied with venous blood from a central venous catheter under medium-level heparinization to feed two perfusion balloon catheters...

  4. Potential role of blood microRNAs as non-invasive biomarkers for early detection of asymptomatic coronary atherosclerosis in obese children with metabolic syndrome.

    Science.gov (United States)

    Omran, Ahmed; Elimam, Dalia; He, Fang; Peng, Jing; Yin, Fei

    2012-12-01

    The pandemic of the childhood obesity represent a major public health problem all over the world. This leads to detection of many health conditions that were previously considered an adulthood diseases. The rise in the prevalence of the obesity and overweight among children means that the world will face an explosion in the prevalence of the metabolic syndrome (MS), which increases the risk of atherosclerotic disease and death in adulthood. The atherosclerotic process has proved to develop silently for decades during childhood and adolescence before the cardiovascular complications such as myocardial infarction and stroke occur. This means that obese children especially with MS could have heart attacks and suffer from heart disease in an age when they should be very healthy, but most of these data either derived from autopsy findings or studies that confirmed the presence of peripheral atherosclerosis. Very early detection of coronary atherosclerosis in obese children with metabolic syndrome through a non invasive method will be of great importance, allowing for early therapeutic intervention. The discovery of microRNAs (miRNAs) is considered a major scientific breakthrough in the last years; recent studies have suggested a potentially important role of miRNAs in the control of diversity aspects of cardiac functions in health and disease including coronary atherosclerosis. Moreover, circulating miRNAs profiles recently used as a non-invasive biomarker for diagnosis of multiple cardiovascular diseases. The identification of distinct circulating miRNA profiles may impact the development of specific miRNAs as biomarkers in pediatric cardiovascular diseases. Therefore, we postulate that some of these circulating miRNAs may be a potential biomarker for early non-invasive diagnosis of coronary atherosclerosis in very early asymptomatic stage in obese children with metabolic syndrome, giving an excellent chance to fight against the first killer in the adult population in

  5. Scaling of cerebral blood perfusion in primates and marsupials.

    Science.gov (United States)

    Seymour, Roger S; Angove, Sophie E; Snelling, Edward P; Cassey, Phillip

    2015-08-01

    The evolution of primates involved increasing body size, brain size and presumably cognitive ability. Cognition is related to neural activity, metabolic rate and rate of blood flow to the cerebral cortex. These parameters are difficult to quantify in living animals. This study shows that it is possible to determine the rate of cortical brain perfusion from the size of the internal carotid artery foramina in skulls of certain mammals, including haplorrhine primates and diprotodont marsupials. We quantify combined blood flow rate in both internal carotid arteries as a proxy of brain metabolism in 34 species of haplorrhine primates (0.116-145 kg body mass) and compare it to the same analysis for 19 species of diprotodont marsupials (0.014-46 kg). Brain volume is related to body mass by essentially the same exponent of 0.70 in both groups. Flow rate increases with haplorrhine brain volume to the 0.95 power, which is significantly higher than the exponent (0.75) expected for most organs according to 'Kleiber's Law'. By comparison, the exponent is 0.73 in marsupials. Thus, the brain perfusion rate increases with body size and brain size much faster in primates than in marsupials. The trajectory of cerebral perfusion in primates is set by the phylogenetically older groups (New and Old World monkeys, lesser apes) and the phylogenetically younger groups (great apes, including humans) fall near the line, with the highest perfusion. This may be associated with disproportionate increases in cortical surface area and mental capacity in the highly social, larger primates.

  6. Cell-free fetal DNA and intact fetal cells in maternal blood circulation: implications for first and second trimester non-invasive prenatal diagnosis.

    Science.gov (United States)

    Bischoff, Farideh Z; Sinacori, Mina K; Dang, Dianne D; Marquez-Do, Deborah; Horne, Cassandra; Lewis, Dorothy E; Simpson, Joe Leigh

    2002-01-01

    Both intact fetal cells as well as cell-free fetal DNA are present in the maternal circulation and can be recovered for non-invasive prenatal genetic diagnosis. Although methods for enrichment and isolation of rare intact fetal cells have been challenging, diagnosis of fetal chromosomal aneuploidy including trisomy 21 in first- and second-trimester pregnancies has been achieved with a 50-75% detection rate. Similarly, cell-free fetal DNA can be reliably recovered from maternal plasma and assessed by quantitative PCR to detect fetal trisomy 21 and paternally derived single gene mutations. Real-time PCR assays are robust in detecting low-level fetal DNA concentrations, with sensitivity of approximately 95-100% and specificity near 100%. Comparing intact fetal cell versus cell-free fetal DNA methods for non-invasive prenatal screening for fetal chromosomal aneuploidy reveals that the latter is at least four times more sensitive. These preliminary results do not support a relationship between frequency of intact fetal cells and concentration of cell-free fetal DNA. The above results imply that the concentration of fetal DNA in maternal plasma may not be dependent on circulating intact fetal cells but rather be a product of growth and cellular turnover during embryonic or fetal development.

  7. BiSpectral Index (BIS monitoring may detect critical hypotension before automated non-invasive blood pressure (NIBP measurement during general anaesthesia; a case report. [v1; ref status: indexed, http://f1000r.es/2oi

    Directory of Open Access Journals (Sweden)

    Matthew M. J. Smith

    2014-01-01

    Full Text Available A patient undergoing general anaesthesia for neurosurgery exhibited an unexpected sudden decrease in the BiSpectral Index (BIS value to near-zero. This prompted the detection of profound hypotension using non-invasive blood pressure (NIBP measurement and expedited urgent assessment and treatment, with the patient making a full recovery. Widely regarded as a ‘depth of anaesthesia’ monitor, this case demonstrates the potential extra clinical benefit BIS may have in the detection of critical incidents such as anaphylaxis during general anaesthesia.

  8. Blood perfusion construction for infrared face recognition based on bio-heat transfer.

    Science.gov (United States)

    Xie, Zhihua; Liu, Guodong

    2014-01-01

    To improve the performance of infrared face recognition for time-lapse data, a new construction of blood perfusion is proposed based on bio-heat transfer. Firstly, by quantifying the blood perfusion based on Pennes equation, the thermal information is converted into blood perfusion rate, which is stable facial biological feature of face image. Then, the separability discriminant criterion in Discrete Cosine Transform (DCT) domain is applied to extract the discriminative features of blood perfusion information. Experimental results demonstrate that the features of blood perfusion are more concentrative and discriminative for recognition than those of thermal information. The infrared face recognition based on the proposed blood perfusion is robust and can achieve better recognition performance compared with other state-of-the-art approaches.

  9. 基于容积脉搏波的无创连续血压测量系统%A Non-invasive Continuous Blood Pressure Measurement System Based on Plethysmographic Pulse Wave

    Institute of Scientific and Technical Information of China (English)

    梁永波; 陈真诚; 朱健铭; 殷世民

    2013-01-01

    Objective To develop a non-invasive continuous blood pressure measurement system without the cuff based on plethysmographic pulse wave. Methods A blood pressure estimation equation was established by the stepwise regression analysis on blood pressure and pulse wave transit time which was extracted from a single circle of plethysmographic pulse wave, and then the non-invasive continuous blood pressure measurement was realized. Results Compared blood pressure value with detection by the system and Yu-Yue brand mercury sphygmomanometer from various populations, the results indicated that the two methods exhibit good coherence , and the measurement error is better than the Association for the Advancement of Medical Instrumentation (AAMI) recommendation standard. Conclusion Compared with traditional blood pressure measurement method , the non-invasive continuous blood pressure measurement method is more convenient. It can measure blood pressure continuously without cuff and invasion, and may have promising application in the future.%目的 设计一种基于容积脉搏波的无袖套连续血压测量系统.方法 从单一容积脉搏波中提取脉搏波传导时间,经逐步回归分析与血压建立血压估算方程,实现无创连续血压测量.结果 通过对不同人群血压检测,并与鱼跃牌水银血压计进行对比,结果表明该方法和传统方法具有较好的测试一致性,测量误差优于美国医疗仪器促进协会(AAMI)推荐标准.结论 该方法同传统血压测量方法相比,测量方便,可彻底摆脱缚带,并能实现无创连续测量,具有更广阔的应用前景.

  10. Non-invasive hemoglobin monitoring.

    Science.gov (United States)

    Joseph, Bellal; Haider, Ansab; Rhee, Peter

    2016-09-01

    Technology has transformed the practice of medicine and surgery in particular over the last several decades. This change in practice has allowed diagnostic and therapeutic tests to be performed less invasively. Hemoglobin monitoring remains one of the most commonly performed diagnostic tests in the United States. Recently, non-invasive hemoglobin monitoring technology has gained popularity. The aim of this article is to review the principles of how this technology works, pros and cons, and the implications of non-invasive hemoglobin technology particularly in trauma surgery.

  11. Retinal functional imager (RFI): non-invasive functional imaging of the retina.

    Science.gov (United States)

    Ganekal, S

    2013-01-01

    Retinal functional imager (RFI) is a unique non-invasive functional imaging system with novel capabilities for visualizing the retina. The objective of this review was to show the utility of non-invasive functional imaging in various disorders. Electronic literature search was carried out using the websites www.pubmed.gov and www.google.com. The search words were retinal functional imager and non-invasive retinal imaging used in combination. The articles published or translated into English were studied. The RFI directly measures hemodynamic parameters such as retinal blood-flow velocity, oximetric state, metabolic responses to photic activation and generates capillary perfusion maps (CPM) that provides retinal vasculature detail similar to flourescein angiography. All of these parameters stand in a direct relationship to the function and therefore the health of the retina, and are known to be degraded in the course of retinal diseases. Detecting changes in retinal function aid early diagnosis and treatment as functional changes often precede structural changes in many retinal disorders.

  12. 监护仪无创血压质量检测的评估与推广%Evaluation and Popularization of Non-invasive Blood Pressure quality Detection for Monitors

    Institute of Scientific and Technical Information of China (English)

    方河炎; 刘曼芳; 郑峰

    2013-01-01

    目的 对监护仪无创血压示值质量进行评估,(设置输出80/50(60) mmhg、100/65(75) mmhg、120/80(93) mmhg、150/100(116) mmhg及200/150(166) mmHg等5组mmhg参数;设定心率80次/min,评估出各个范围的质量状态.方法使用FLUKE BP Pump2无创血压模拟器内置袖带的质量检测方案,随机抽取南方医院15台HP MP20监护仪和15台GE Dash2500监护仪进行质量检测,采用平均差与标准方差进行分析.结果两种监护仪的实际血压值与设定血压值均存在差异.结论利用血压模拟器对监护仪无创血压质量检测,并结合数理统计学知识分析,此方案具有可行性,可推广到呼吸机流量、输液泵流速及除颤/起搏仪的质量检测与评估.%Objective To evaluate quality of non-invasive blood pressure value of monitors, set the output 80/50 (60), 100/65 (75), 120/80 (93), 150/100 (116) and 200/150 (166) and heart rate 80 beats/min, to assess the quality status of each range. Methods To use the FLUKE BP Pump2 non-invasive blood pressure simulator, the built-in cuff quality detection program, randomly select 15 HP MP20 monitors and 15 GE Dash2500 monitor from Nanfang Hospital to carry out quality detection. The mean difference and standard deviation are analyzed. Results The actual blood pressure value and set blood pressure value of the two monitors are different. Conclusion The program which uses a pressure simulator to test quality of non-invasive blood pressure for monitors, and analysis based on the knowledge of mathematical statistics, can be extended to the ventilator flow, infusion pump flow rate and quality detection and evaluation of defibrillator/pacemaker.

  13. Non-invasive measurement of hepatic oxygenation by an oxygen electrode in human orthotopic liver transplantation.

    Science.gov (United States)

    Seifalian, A M; Mallett, S; Piasecki, C; Rolles, K; Davidson, B R

    2000-06-01

    Precise evaluation of graft reperfusion is difficult in clinical liver transplantation. The oxygen electrode (OE) is a novel technique to detect blood flow indirectly by measuring the quantity of oxygen which can diffuse from the hepatic tissue to the surface electrode. Application of the surface OE does not influence the liver blood flow or parenchymal perfusion. Adequate graft oxygenation is essential to the outcome of organ transplantation and has not previously been analysed intra-operatively in liver transplant recipients. The OE was applied to the surface of the graft intra-operatively in 22 human liver grafts after restoring portal vein and hepatic artery inflow. OE readings were compared with liver blood flow using an electromagnetic flowmeter (EMF). Intra-operative haemodynamics and donor organ parameters known to influence graft function were correlated with the OE readings. There was a significant correlation (r=0.89; poxygenation using the OE and total liver blood flow measured by EMF. The tissue oxygenation measurements were reproducible with a coefficient of variation of 5%. The hepatic tissue oxygenation increased significantly from baseline following venous reperfusion of the graft (282+/-23 vs 3107+/-288 (+/-SE) nA, poxygen perfusion. There was significant negative correlation (r=0.80, poxygenation. The OE provides a reliable, cheap and non-invasive method of monitoring liver graft oxygenation and perfusion during transplantation.

  14. A SEMICONDUCTOR-LASER USED FOR DIRECT MEASUREMENT OF THE BLOOD PERFUSION OF TISSUE

    NARCIS (Netherlands)

    DEMUL, FFM; KOELINK, MH; WEIJERS, AL; GREVE, J; AARNOUDSE, JG; GRAAFF, R; DASSEL, ACM

    1993-01-01

    An instrument consisting merely of a semiconductor laser in its own housing was used to measure the blood perfusion in tissue. Use is made of the feedback of Doppler-scattered light to the photodiode in the laser housing. A recording perfusion of a finger under occlusion of blood flow in the arm is

  15. SELF-MIXING LASER-DOPPLER VELOCIMETRY OF LIQUID FLOW AND OF BLOOD PERFUSION IN TISSUE

    NARCIS (Netherlands)

    DEMUL, FFM; KOELINK, MH; WEIJERS, AL; GREVE, J; AARNOUDSE, JG; GRAAFF, R; DASSEL, ACM

    1992-01-01

    The velocimetry method of self-mixing, i.e., the feedback of Doppler-scattered light into the laser cavity, is used for the measurement of liquid flow and of blood perfusion in human tissue. The method is eIucidated by the registration of the blood perfusion of a finger under repeated occlusion of t

  16. PERFUSION PRESSURE AND RENAL BLOOD FLOW: THEIR RELATIONSHIP AND DIFFERENCES

    Directory of Open Access Journals (Sweden)

    Carlos G. Musso, MD. PhD.1,2, Manuel Vilas, MD.

    2014-05-01

    Full Text Available The concepts of renal perfusion pressure (RPP and renal blood flow (RBF are usually confused, but although they are intimately related, they are not strictly the same. RPP originates from the minute cardiac volume and is, therefore, the cause of RBF, which generates glomerular filtration and as a consequence, also induces the urinary flow. On the other hand, whereas RPP can be subject to fluctuations, the same happens to RBF though at a much lower level due to the existence of physiological mechanisms, such as self-regulation of the flow and tubule-glomerular feed-back. We conclude that there is a dependence of the RBF in relation with RPP, with the former acting as the final responsible of the glomerular filtration.

  17. Non-invasive neural stimulation

    Science.gov (United States)

    Tyler, William J.; Sanguinetti, Joseph L.; Fini, Maria; Hool, Nicholas

    2017-05-01

    Neurotechnologies for non-invasively interfacing with neural circuits have been evolving from those capable of sensing neural activity to those capable of restoring and enhancing human brain function. Generally referred to as non-invasive neural stimulation (NINS) methods, these neuromodulation approaches rely on electrical, magnetic, photonic, and acoustic or ultrasonic energy to influence nervous system activity, brain function, and behavior. Evidence that has been surmounting for decades shows that advanced neural engineering of NINS technologies will indeed transform the way humans treat diseases, interact with information, communicate, and learn. The physics underlying the ability of various NINS methods to modulate nervous system activity can be quite different from one another depending on the energy modality used as we briefly discuss. For members of commercial and defense industry sectors that have not traditionally engaged in neuroscience research and development, the science, engineering and technology required to advance NINS methods beyond the state-of-the-art presents tremendous opportunities. Within the past few years alone there have been large increases in global investments made by federal agencies, foundations, private investors and multinational corporations to develop advanced applications of NINS technologies. Driven by these efforts NINS methods and devices have recently been introduced to mass markets via the consumer electronics industry. Further, NINS continues to be explored in a growing number of defense applications focused on enhancing human dimensions. The present paper provides a brief introduction to the field of non-invasive neural stimulation by highlighting some of the more common methods in use or under current development today.

  18. Photoacoustic & pulsed laser-doppler monitoring of blood concentration and perfusion in tissue

    OpenAIRE

    Kolkman, Roy Gerardus Maria

    2002-01-01

    In medicine there are situations that require continuous bedside monitoring of perfusion and blood volume. Such a situation can occur when children are born prematurely. Those children have a high risk to develop a handicap, which is most likely caused by cerebral damage due to impaired brain perfusion. Monitoring cerebral perfusion can provide information for preventive treatment. In this thesis we have explored the potential of photoacoustics and laser Doppler flowmetry for measurement of c...

  19. Scintigraphic control of blood vessels in regional perfusion with cytostatics

    Energy Technology Data Exchange (ETDEWEB)

    Blazek, J.; Broz, J. (Krajska Nemocnice s Poliklinikou, Ceske Budejovice (Czechoslovakia))

    1982-12-01

    After administration of sup(99m)Tc-MAA or sup(113m)In-MAA into the perfusion system during regional perfusion therapy with cytostatics of malignomas in the maxillo-facial area it is possible to obtain by subsequent scintigraphic visualization of the distribution of radioactivity an accurate topographic picture of the perfusion in the appropriate area. The method is free from complications and there are no contraindications. The paper is supplemented by scintigrams.

  20. Radionuclide Tracers for Myocardial Perfusion Imaging and Blood Flow Quantification.

    Science.gov (United States)

    deKemp, Robert A; Renaud, Jennifer M; Klein, Ran; Beanlands, Rob S B

    2016-02-01

    Myocardial perfusion imaging is performed most commonly using Tc-99m-sestamibi or tetrofosmin SPECT as well as Rb-82-rubidium or N-13-ammonia PET. Diseased-to-normal tissue contrast is determined by the tracer retention fraction, which decreases nonlinearly with flow. Reduced tissue perfusion results in reduced tracer retention, but the severity of perfusion defects is typically underestimated by 20% to 40%. Compared to SPECT, retention of the PET tracers is more linearly related to flow, and therefore, the perfusion defects are measured more accurately using N-13-ammonia or Rb-82.

  1. NON-INVASIVE PRENATAL DIAGNOSIS: A REVIEW

    Directory of Open Access Journals (Sweden)

    Madhusudan Dey, Sumita Agarwal and Sumedha Sharma

    2013-04-01

    Full Text Available ABSTRACT: Aneuploidies are one of the important causes of perinatal morbidity and mortality. Initially screening for aneuploidies started with maternal age risk estimation. Later on, serum testing for biochemical markers and ultrasound markers were added. Women detected to be at high risk for aneuploidies were offered invasive testing. Recently, various methods including non-invasive prenatal testing (NIPT by analysis of cell-free fetal DNA (cffDNA in maternal blood has shown promise for highly accurate detection of common fetal autosomal trisomies. Incorporating these new non-invasive technologies into clinical practice will impact the current prenatal screening paradigm for fetal aneuploidy, in which genetic counselling plays an integral role. The advantage of the technique being elimination of risks such as miscarriage associated with invasive diagnostic procedures. But then this new technique has its own set of technical limitations and ethical issues at present and further research is required before implementation. Data was obtained through a literature search via Pubmed and Google as well as detailed search of our library database.

  2. Non-invasive light observer

    CERN Document Server

    Morichetti, Francesco; Carminati, Marco; Ferrari, Giorgio; Sampietro, Marco; Strain, Michael; Sorel, Marc; Melloni, Andrea

    2013-01-01

    Photonic technologies lack non-invasive monitoring tools to inspect the light inside optical waveguides. This is one of the main barriers to large scale of integration, even though photonic platforms are potentially ready to host several thousands of elements on a single chip. Here, we demonstrate non-invasive light observation in silicon photonics devices by exploiting photon interaction with intra-gap energy states localized at the waveguide surface. Light intensity is measured through a ContactLess Integrated Photonic Probe (CLIPP) that introduces no measurable extra-photon absorption and a phase perturbation as low as 0.2 mrad, comparable to thermal fluctuations of less than 3 mK. Multipoint light monitoring is demonstrated with a sensitivity of -30 dBm and a dynamic range of 40 dB. CLIPP technology is simple, inherently CMOS compatible, and scalable to hundreds of probing points per chip. This concept provides a viable way to real-time conditioning and feedback control of densely-integrated photonic syst...

  3. The effects of scraping therapy on local temperature and blood perfusion volume in healthy subjects.

    Science.gov (United States)

    Xu, Qin-Yan; Yang, Jin-Sheng; Zhu, Bing; Yang, Li; Wang, Ying-Ying; Gao, Xin-Yan

    2012-01-01

    Objective. We aim to study the therapeutic effects of scraping by investigating the changes of temperature and local blood perfusion volume in healthy subjects after scraping stimulation, and to explore the mechanism of scraping stimulation from the points of microcirculation and energy metabolism. Methods. Twenty-three health subjects were included in this study. Local blood perfusion volume and body surface temperature was detected at 5 min before scraping stimulation, 0, 15, 30, 60 and 90 min after scraping using Laser Doppler imager and infrared thermograph. Results. Significant increase was noted in the blood perfusion volume in the scraping area within 90 minutes compared to the baseline level and non-scraping area (P scraping area, an increase of body temperature with an average of 1°C was observed after scraping stimulation (P Scraping can significantly improve the blood perfusion volume and increase the temperature in the scraping area, promoting the local blood circulation and energy metabolism.

  4. Retinal hemodynamic oxygen reactivity assessed by perfusion velocity, blood oximetry and vessel diameter measurements

    DEFF Research Database (Denmark)

    Klefter, Oliver Niels; Lauritsen, Anne Øberg; Larsen, Michael

    2015-01-01

    PURPOSE: To test the oxygen reactivity of a fundus photographic method of measuring macular perfusion velocity and to integrate macular perfusion velocities with measurements of retinal vessel diameters and blood oxygen saturation. METHODS: Sixteen eyes in 16 healthy volunteers were studied at two...... measurements may provide comprehensive information about retinal metabolism....

  5. Steroid concentrations in plasma, whole blood and brain: effects of saline perfusion to remove blood contamination from brain.

    Directory of Open Access Journals (Sweden)

    Matthew D Taves

    Full Text Available The brain and other organs locally synthesize steroids. Local synthesis is suggested when steroid levels are higher in tissue than in the circulation. However, measurement of both circulating and tissue steroid levels are subject to methodological considerations. For example, plasma samples are commonly used to estimate circulating steroid levels in whole blood, but steroid levels in plasma and whole blood could differ. In addition, tissue steroid measurements might be affected by blood contamination, which can be addressed experimentally by using saline perfusion to remove blood. In Study 1, we measured corticosterone and testosterone (T levels in zebra finch (Taeniopygia guttata plasma, whole blood, and red blood cells (RBC. We also compared corticosterone in plasma, whole blood, and RBC at baseline and after 60 min restraint stress. In Study 2, we quantified corticosterone, dehydroepiandrosterone (DHEA, T, and 17β-estradiol (E₂ levels in the brains of sham-perfused or saline-perfused subjects. In Study 1, corticosterone and T concentrations were highest in plasma, significantly lower in whole blood, and lowest in RBC. In Study 2, saline perfusion unexpectedly increased corticosterone levels in the rostral telencephalon but not other regions. In contrast, saline perfusion decreased DHEA levels in caudal telencephalon and diencephalon. Saline perfusion also increased E₂ levels in caudal telencephalon. In summary, when comparing local and systemic steroid levels, the inclusion of whole blood samples should prove useful. Moreover, blood contamination has little or no effect on measurement of brain steroid levels, suggesting that saline perfusion is not necessary prior to brain collection. Indeed, saline perfusion itself may elevate and lower steroid concentrations in a rapid, region-specific manner.

  6. Establishing baseline levels of trace elements in blood and skin of bottlenose dolphins in Sarasota Bay, Florida: Implications for non-invasive monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Bryan, Colleen E. [National Institute of Standards and Technology, Hollings Marine Laboratory, 331 Fort Johnson Road, Charleston, South Carolina 29412 (United States); College of Charleston, Grice Marine Laboratory, 205 Fort Johnson Road, Charleston, South Carolina 29412 (United States)], E-mail: colleen.bryan@nist.gov; Christopher, Steven J. [National Institute of Standards and Technology, Hollings Marine Laboratory, 331 Fort Johnson Road, Charleston, South Carolina 29412 (United States); Balmer, Brian C.; Wells, Randall S. [Chicago Zoological Society c/o Mote Marine Laboratory, 1600 Ken Thompson Parkway, Sarasota, Florida 34236 (United States)

    2007-12-15

    Several major unusual mortality events occurring in recent years have increased the level of concern for the health of bottlenose dolphin populations along the United States Atlantic and Gulf of Mexico coasts. Trace element concentrations were examined in a population of free-ranging dolphins in Sarasota Bay, Florida, in order to develop a benchmark for future comparisons within and between populations. Whole blood (n = 51) and skin (n = 40) samples were collected through capture and release health assessment events during 2002-2004. Samples were analyzed for Al, V, Cr, Mn, Cu, Zn, As, Se, Rb, Sr, Mo, Cd, and Pb by inductively coupled plasma mass spectrometry (ICPMS) and Hg via atomic fluorescence spectrometry (AFS). Trace element concentrations (wet mass) in skin were 2 to 45 times greater than blood, except Cu was approximately 1.5 times higher in blood. Statistically strong correlations (p < 0.05) were found for V, As, Se, Rb, Sr, and Hg between blood and skin demonstrating that these tissues can be used as effective non-lethal monitoring tools. The strongest correlation was established for Hg (r = 0.9689) and concentrations in both blood and skin were above the threshold at which detrimental effects are observed in other vertebrate species. Female dolphins had significantly greater Hg concentrations in blood and skin and Pb concentrations in skin, relative to males. Calves exhibited significantly lower V, As, and Hg concentrations in blood and V and Hg concentrations in skin, relative to other age classes. Rubidium and Cu concentrations in skin were greatest in subadults and calves, respectively. In blood, V, Zn, and As concentrations were significantly greater in winter, relative to summer, and the opposite trend was observed for Rb and Sr concentrations. In skin, Cu and Zn concentrations were significantly greater in winter, relative to summer, and the opposite trend was observed for Mn, Rb, Cd, and Pb concentrations. The baseline concentrations and trends

  7. Availability of Floating-Reference Theory to Non-Invasive Blood Component Measurement by Optical Technology%血液成分无创光学检测中浮动基准理论的适用性

    Institute of Scientific and Technical Information of China (English)

    蒋景英; 龚启亮; 徐可欣

    2012-01-01

    Based on the studies of floating-reference theory(FRT) applied to non-invasive optical blood glucose sensing, this paper further investigated the availability of FRT in measuring other blood compo-nents, like bilirubin. According to the conditions of the radial reference location, the results of Monte Carlo simulation show no appearance of radial reference location in non-invasive bilirubin measurement. While the study on the replacement effect of bilirubin and water shows that, at the wavelength of 524 run, the absorption value of bilirubin solution has no relationship with its concentration. Therefore, this wave-length is regarded as the reference wavelength, and in the further study, it can be used to remove the in-fluence caused by the change of environment and background. In general, the application of FRT in blood glucose and bilirubin shows the specificity of floating reference location and floating reference wave-length in measuring different blood components by optical technology within the designated wavelength, which further improves and extends the application of FRT.%在浮动基准理论(FRT)应用于血糖无创光学检测研究成果的基础上,进一步研究其在其他血液成分(如胆红素)无创光学检测中的适用性.根据径向检测基准位置存在的条件,经蒙特卡洛模拟的结果表明胆红素测量中难以找到浮动基准位置;而通过研究胆红素与水的置换效应,发现在波长524 nm处吸光度值与胆红素的浓度无关,将该波长作为基准波长,实际测量中可以用于去除背景噪声和环境干扰.综合FRT在血糖及胆红素两种不同血液成分中应用的研究结果表明:对于不同检测成分,在相应的检测波段,浮动基准位置和浮动基准波长有一定的特异性,从而进一步完善和扩展了FRT的应用领域.

  8. TNO finger pressure reference guide: guide for the non-invasive finger blood pressure measurement and recording systems Portapres and Finometer

    NARCIS (Netherlands)

    2001-01-01

    With Portapres and Finometer continuous beat-to-beat finger blood pressure is measured. Although it is relatively easy to perform measurements, a basic understanding of the principles of the device is recommended to obtain reliable measurements. This reference guide addresses the volume-clamp method

  9. Remote non-invasive stereoscopic imaging of blood vessels: first in-vivo results of a new multispectral contrast enhancement technology

    NARCIS (Netherlands)

    Wieringa, F.P.; Mastik, F.; Cate, F.J. ten; Neumann, H.A.M.; Steen, A.F.W. van der

    2006-01-01

    We describe a contactless optical technique selectively enhancing superficial blood vessels below variously pigmented intact human skin by combining images in different spectral bands. Two CMOS-cameras, with apochromatic lenses and dual-band LED-arrays, simultaneously streamed Left (L) and Right (R)

  10. TNO finger pressure reference guide: guide for the non-invasive finger blood pressure measurement and recording systems Portapres and Finometer

    NARCIS (Netherlands)

    2001-01-01

    With Portapres and Finometer continuous beat-to-beat finger blood pressure is measured. Although it is relatively easy to perform measurements, a basic understanding of the principles of the device is recommended to obtain reliable measurements. This reference guide addresses the volume-clamp method

  11. Remote non-invasive stereoscopic imaging of blood vessels: first in-vivo results of a new multispectral contrast enhancement technology

    NARCIS (Netherlands)

    Wieringa, F.P.; Mastik, F.; Cate, F.J. ten; Neumann, H.A.M.; Steen, A.F.W. van der

    2006-01-01

    We describe a contactless optical technique selectively enhancing superficial blood vessels below variously pigmented intact human skin by combining images in different spectral bands. Two CMOS-cameras, with apochromatic lenses and dual-band LED-arrays, simultaneously streamed Left (L) and Right (R)

  12. Continuous blood pressure monitoring via non-invasive radial artery applanation tonometry and invasive arterial catheter demonstrates good agreement in patients undergoing colon carcinoma surgery.

    Science.gov (United States)

    Sun, Jing; Chen, Hanjian; Zheng, Jun; Mao, Bin; Zhu, Shengmei; Feng, Jingyi

    2016-12-20

    Radial artery applanation tonometry (RAAT) has been developed and utilized for continuous arterial pressure monitoring. However, evidence is lacking to clinically verify the RAAT technology and identify appropriate patient groups before routine clinical use. This study aims to evaluate the RAAT technology by comparing systolic blood pressure (SBP), mean blood pressure (MBP) and diastolic blood pressure (DBP) values in patients undergoing colon carcinoma surgery. Blood Pressure (BP) values obtained via RAAT (TL-300, Tensys Medical Inc., San Diego, CA, USA) and conventional arterial catheterization from 30 colon carcinoma surgical patients were collected and compared via Bland-Atman method, linear regression and 4-quadrant plot concordance analysis. For SBPs, MBPs and DBPs, means of the differences (±standard deviation; 95% limits of agreement) were -0.9 (±7.6; -15.7 to 13.9) mmHg, 3.1 (±6.5; -9.6 to 15.8) mmHg and 4.3 (±7.4; -10.3 to 18.8) mmHg, respectively. Linear regression coefficients of determination were 0.8706 for SBPs, 0.8353 for MBPs and 0.6858 for DBPs. Four-quadrant concordance correlation coefficients were 0.8740, 0.8522 and 0.7108 for SBPs, MBPs and DBPs, respectively. A highly selected patient collective undergoing colon carcinoma surgery was studied. BP measurements obtained via the TL-300 had clinically acceptable agreement with that acquired invasively using an arterial catheter. For use in clinical routine, it is necessary to take measures for improvement regarding movement artifacts and dilution of noise. A large sample size of patients under various conditions is also needed to further evaluate the RAAT technology before clinically routine use.

  13. Progress of MIR Non-Invasive Blood Glucose Determination and Effect of Stratum Corneum%中红外无创血糖研究进展并论角质层影响

    Institute of Scientific and Technical Information of China (English)

    陈星旦; 王动民; 卢启鹏; 丁海泉

    2011-01-01

    The progress of non-invasive blood glucose determination based on mid-infrared spectroscopy is introduced firstly. After this, the effect of stratum corneum (SC) on blood glucose determination is studied by experiment while interstitial fluid (ISF) is collected on the skin surface. Using the spectra of simulated ISF, partial least square regression (PLSR) calibration model of glucose determination is established, and the value of root mean squares error of cross validation (RMSECV) is 9.6 mg/dL. While including the interference of stratum corneum from three volenteers individually, three RMSECV are obtained, and they are 17.4, 16.3 and 17.1 mg/dL, respectively. The results show that the effects of SC from different volenteers are the same nearly; including the interference of SC, the accuracy of the non-invasive blood glucose determination based on attenuated total reflection mid-infrared spectroscopy can reach 18 mg/dL.%在介绍中红外无创血糖研究进展的基础上,实验探讨了组织液渗透到手指皮肤表面时,角质层对血糖测量的影响.加入角质层干扰信息前,用偏最小二乘法(PLSR)建立了模拟组织液中葡萄糖定标模型,其内部交叉验证均方差(RMSECV)为9.6 mg/dL;加入三个志愿者手指皮肤吸收的干扰信息后,所得三个模型的RMSECV分别为17.4,16.3和17.1 mg/dL.结果表明,当组织液渗透到手指皮肤表面时,不同志愿者的角质层对定标模型的影响程度大致相同;计入角质层的干扰,中红外光谱无创血糖的检测精度有望达到18 mg/dL.

  14. Blood perfusion and pH monitoring in organs by laser-induced fluorescence spectroscopy

    Science.gov (United States)

    Vari, Sandor G.; Papazoglou, Theodore G.; Pergadia, Vani R.; Stavridi, Marigo; Snyder, Wendy J.; Papaioannou, Thanassis; Duffy, J. T.; Weiss, Andrew B.; Thomas, Reem; Grundfest, Warren S.

    1994-01-01

    Sensitivity of laser-induced fluorescence spectroscopy (LIFS) in detecting a change in tissue pH, and blood perfusion was determined. Rabbits were anesthetized, paralyzed, and mechanically ventilated. The arterial and venous blood supplies of the kidney were isolated and ligated to alter the perfusion. The femoral artery was cannulated to extract samples for blood gas analysis. A 308-nm XeCl was used as an excitation source. A 600 micrometers core diameter fiber was used for fluorescence acquisition, and the spectra analyzed by an optical multichannel analyzer (EG & G, OMA III). the corresponding intensity ratio R equals INADH / ICOLL was used as an index for respiratory acidosis. Blood perfusion was assessed using the following algorithm: (IELAS minus ICOLL) divided by (INADH minus ICOLL). The intensity ratio linearly decreased with the reduction of blood perfusion. When we totally occluded the artery the ratio decreased tenfold when compared to the ratio of a fully perfused kidney. Results of monitoring blood acidosis by laser-induced fluorescence spectroscopy shows a significant trend between pH and intensity ratio. Since all the slopes were negative, there is an obvious significant correlation between the pH and NADH.COLLAGEN RATIO. Blue-light-induced fluorescence measurements and ratio fluorometry is a sensitive method for monitoring blood perfusion and acidity or alkalinity of an organ.

  15. The Influence of Oxytocin on the Blood Perfusion of Uterine Fibroids: Contrast-enhanced Ultrasonography Evaluation

    Directory of Open Access Journals (Sweden)

    Yang Wang

    2016-03-01

    Conclusion: This CEUS study demonstrated that the use of parenteral oxytocin can significantly reduce the blood perfusion of the uterine fibroids, which may help to enhance the therapeutic efficacy for high intensity focused ultrasound ablation of uterine fibroids.

  16. Blood temperature and perfusion to exercising and non-exercising human limbs

    DEFF Research Database (Denmark)

    González-Alonso, José; Calbet, José A. L.; Boushel, Robert

    2015-01-01

    NEW FINDINGS: What is the central question of this study? Temperature-sensitive mechanisms are thought to contribute to blood-flow regulation, but the relationship between exercising and non-exercising limb perfusion and blood temperature is not established. What is the main finding and its...... importance? The close coupling among perfusion, blood temperature and aerobic metabolism in exercising and non-exercising extremities across different exercise modalities and activity levels and the tight association between limb vasodilatation and increases in plasma ATP suggest that both temperature......- and metabolism-sensitive mechanisms are important for the control of human limb perfusion, possibly by activating ATP release from the erythrocytes.  Temperature-sensitive mechanisms may contribute to blood-flow regulation, but the influence of temperature on perfusion to exercising and non-exercising human...

  17. Muscle Tissue Saturation Compared With Muscle Tissue Perfusion During Low Blood Flows

    DEFF Research Database (Denmark)

    Thomassen, Sisse Anette; Kjærgaard, Benedict; Olsen Alstrup, Aage Kristian

    2017-01-01

    OBJECTIVE: To investigate whether changes in muscle tissue perfusion measured with positron emission tomography would be reflected by parallel changes in muscle tissue oxygen saturation (StO2) measured using near-infrared spectroscopy during high and low blood flow levels achieved using...... blood flow of either 47.5 or 35 mL/kg/min was applied for 1 hour followed by a blood flow of 60 mL/kg/min for an additional hour. Regional StO2 was measured continuously by placing a near-infrared spectroscopy electrode on the skin above the gracilis muscle of the noncannulated back leg. Muscle tissue...... systemic ischemia during low CPB blood flow. StO2 remained high until muscle tissue perfusion decreased to about 50%, after which StO2 paralleled the linear decrease in muscle tissue perfusion. CONCLUSION: In an experimental CPB animal model, StO2 was stable until muscle tissue perfusion was reduced...

  18. The Effects of Scraping Therapy on Local Temperature and Blood Perfusion Volume in Healthy Subjects

    OpenAIRE

    Qin-Yan Xu; Jin-Sheng Yang; Bing Zhu; Li Yang; Ying-Ying Wang; Xin-Yan Gao

    2012-01-01

    Objective. We aim to study the therapeutic effects of scraping by investigating the changes of temperature and local blood perfusion volume in healthy subjects after scraping stimulation, and to explore the mechanism of scraping stimulation from the points of microcirculation and energy metabolism. Methods. Twenty-three health subjects were included in this study. Local blood perfusion volume and body surface temperature was detected at 5 min before scraping stimulation, 0, 15, 30, 60 and 90 ...

  19. Diagnóstico prenatal no invasivo: Ácidos nucleicos de origen fetal en sangre materna Non invasive prenatal diagnosis: Fetal nucleic acid analysis in maternal blood

    Directory of Open Access Journals (Sweden)

    Carla Sesarini

    2010-12-01

    decade, the presence of cell-free fetal DNA in maternal blood has been identified. These fetal DNA fragments would derive from the placenta and are not detected after delivery, making them a source of fetal material for carrying out diagnosis techniques using maternal blood. However, the vast majority of cell free DNA in maternal circulation is of maternal origin, with the fetal component contributing from 3% to 6% and rising towards term. Available methodologies do not allow separation of fetal from maternal cell free DNA, so current applications have been focused on the analysis of genes not present in the mother, such as Y chromosome sequences, or RHD gene in RhD-negative women, or paternal or de novo mutations. Also, the detection of cell-free fetal RNA in maternal blood offers the possibility of obtaining information regarding genetic expression profiles of embrionic tissues, and using genes expressed only at the feto-placental unit, controls for the presence of fetal material could be established, regardless of maternal genetic tissue. The present article describes the evidences regarding the passage of fetal nucleic acids to maternal circulation, its current prenatal diagnosis application and possible future perspectives.

  20. A pilot study using laser-based technique for non-invasive diagnostics of hypertensive conditions in mice

    Science.gov (United States)

    Litvinova, Karina S.; Ahmad, Shakil; Wang, Keqing; Rafailov, Ilya E.; Sokolovski, Sergei G.; Zhang, Lin; Rafailov, Edik U.; Ahmed, Asif

    2016-02-01

    Endothelial dysfunction is directly linked to preeclampsia, a maternal hypertensive condition that is life threating for both the mother and the baby. Epidemiological studies show that women with a history of pre-eclampsia have an elevated risk for cardiovascular disease. Here we report a new non-invasive diagnostic test for preeclampsia in mice that allows us to non-invasively assess the condition of the animals during the experiment and treatment in established models of preeclampsia. A laser-based multifunctional diagnostics system (LAKK-M) was chosen to carry out non-invasive analysis of multiple parameters. The device was used to simultaneously record the microcirculatory blood flow and oxygen saturation, as well as fluorescence levels of endogenous fluorophores. Preliminary experiments were conducted on adenoviral (Ad-)- mediated overexpression of sFlt-1 (Ad-sFlt-1) to mimic preeclampsialike symptoms in mice. The recorded data displayed the ability of the LAKK-M diagnostics device to detect significant differences in perfusion measurements between the control and Ad-sFlt-1 treatment. Preliminary results provide a potential avenue to employ these diagnostics technology to monitor and aid in maintaining control of live animal conditions throughout the experiment and treatment.

  1. [Study on optimal selection of structure of vaneless centrifugal blood pump with constraints on blood perfusion and on blood damage indexes].

    Science.gov (United States)

    Hu, Zhaoyan; Pan, Youlian; Chen, Zhenglong; Zhang, Tianyi; Lu, Lijun

    2012-12-01

    This paper is aimed to study the optimal selection of structure of vaneless centrifugal blood pump. The optimal objective is determined according to requirements of clinical use. Possible schemes are generally worked out based on structural feature of vaneless centrifugal blood pump. The optimal structure is selected from possible schemes with constraints on blood perfusion and blood damage indexes. Using an optimal selection method one can find the optimum structure scheme from possible schemes effectively. The results of numerical simulation of optimal blood pump showed that the method of constraints of blood perfusion and blood damage is competent for the requirements of selection of the optimal blood pumps.

  2. Measuring blood delivery to solitary pulmonary nodules using perfusion magnetic resonance imaging

    Science.gov (United States)

    Zheng, Wei; Wang, Zhifeng; Shen, Li; Gao, Ling; Ford, James C.; Makedon, Fillia S.; Pearlman, Justin D.

    2006-03-01

    With perfusion magnetic resonance imaging (pMRI), perfusion describes the amount of blood passing through a block of tissue in a certain period of time. In pMRI, the tissue having more blood passing through will show higher intensity value as more contrast-labeled blood arrives. Perfusion reflects the delivery of essential nutrients to a block of tissue, and is an important parameter for the tissue status. Considering solitary pulmonary nodules (SPN), perfusion differences between malignant and benign nodules have been studied by different techniques. Much effort has been put into its characterization. In this paper, we proposed and implemented extraction of the SPN time intensity profile to measure blood delivery to solitary pulmonary nodules, describing their perfusion effects. In this method, a SPN time intensity profile is created based on intensity values of the solitary pulmonary nodule in lung pMRI images over time. This method has two steps: nodule tracking and profile clustering. Nodule tracking aligns the solitary pulmonary nodule in pMRI images taken at different time points, dealing with nodule movement resulted from breathing and body movement. Profile clustering implements segmentation of the nodule region and extraction of the time intensity profile of a solitary pulmonary nodule. SPN time intensity profiles reflect patterns of blood delivery to solitary pulmonary nodules, giving us a description of perfusion effect and indirect evidence of tumor angiogenesis. Analysis on SPN time intensity profiles will help the diagnosis of malignant nodules for early lung cancer detection.

  3. Hepatic blood perfusion estimated by dynamic contrast-enhanced computed tomography in pigs

    DEFF Research Database (Denmark)

    Winterdahl, Michael; Sørensen, Michael; Keiding, Inger Susanne;

    2012-01-01

    The aim of this study was to determine whether dynamic contrast-enhanced computed tomography (DCE-CT) and the slope method can provide absolute measures of hepatic blood perfusion from the hepatic artery (HA) and portal vein (PV) at experimentally varied blood flow rates.......The aim of this study was to determine whether dynamic contrast-enhanced computed tomography (DCE-CT) and the slope method can provide absolute measures of hepatic blood perfusion from the hepatic artery (HA) and portal vein (PV) at experimentally varied blood flow rates....

  4. Alginate/PEG based microcarriers with cleavable crosslinkage for expansion and non-invasive harvest of human umbilical cord blood mesenchymal stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Li, Chunge [Tianjin Key Laboratory of Composite and Functional Materials, School of Materials Science and Engineering, Tianjin University, No. 92, Weijin Road, Tianjin 300072 (China); Qian, Yufeng [Department of Chemistry and Biochemistry, University of Texas at Austin, 2500 Speedway, Austin, TX 78712 (United States); Zhao, Shuang [Tianjin Key Laboratory of Composite and Functional Materials, School of Materials Science and Engineering, Tianjin University, No. 92, Weijin Road, Tianjin 300072 (China); Yin, Yuji, E-mail: yinyuji@tju.edu.cn [Tianjin Key Laboratory of Composite and Functional Materials, School of Materials Science and Engineering, Tianjin University, No. 92, Weijin Road, Tianjin 300072 (China); Li, Junjie, E-mail: li41308@tju.edu.cn [Tianjin Key Laboratory of Composite and Functional Materials, School of Materials Science and Engineering, Tianjin University, No. 92, Weijin Road, Tianjin 300072 (China); Department of Advanced Interdisciplinary Studies, Institute of Basic Medical Sciences and Tissue Engineering Research Center, Academy of Military Medical Sciences, No. 27, Taiping Road, Beijing 100850 (China)

    2016-07-01

    Porous microcarriers are increasingly used to expand and harvest stem cells. Generally, the cells are harvested via proteolytic enzyme treatment, which always leads to damages to stem cells. To address this disadvantage, a series of alginate/PEG (AL/PEG) semi-interpenetrating network microcarriers are prepared in this study. In this AL/PEG system, the chemically cross-linked alginate networks are formed via the reaction between carboxylic acid group of alginate and di-terminated amine groups of cystamine. PEG is introduced to modulate the degradation of microcarriers, which does not participate in this cross-linked reaction, while it interpenetrates in alginate network via physical interactions. In addition, chitosan are coated on the surface of AL/PEG to improve the mechanical strength via the electrostatic interactions. Biocompatible fibronectin are also coated on these microcarriers to modulate the biological behaviors of cells seeded in microcarriers. Results suggest that the size of AL/PEG microcarriers can be modulated via adjusting the contents and molecular weight of PEG. Moreover, the microcarriers are designed to be degraded with cleavage of disulfide crosslinkage. By changing the type and concentration of reductant, the ratio of AL to PEG, and the magnitude of chitosan coating, the degradation ability of AL/PEG microcarriers can be well controlled. In addition, AL/PEG microcarriers can support the attachment and proliferation of human umbilical cord blood mesenchymal stem cells (hUCB-MSCs). More importantly, the expanded hUCB-MSCs can be detached from microcarriers after addition of reductant, which indeed reduce the cell damage caused by proteolytic enzyme treatment. Therefore, it is convinced that AL/PEG based microcarriers will be a promising candidate for large-scale expansion of hUCB-MSCs. - Graphical abstract: Alginate/PEG IPN microcarriers can support the attachment and expansion of hUCB-MSCs. More importantly, the expanded cells can be harvested

  5. Non-invasive, neuron-specific gene therapy by focused ultrasound-induced blood-brain barrier opening in Parkinson's disease mouse model.

    Science.gov (United States)

    Lin, Chung-Yin; Hsieh, Han-Yi; Chen, Chiung-Mei; Wu, Shang-Rung; Tsai, Chih-Hung; Huang, Chiung-Yin; Hua, Mu-Yi; Wei, Kuo-Chen; Yeh, Chih-Kuang; Liu, Hao-Li

    2016-08-10

    Focused ultrasound (FUS)-induced with microbubbles (MBs) is a promising technique for noninvasive opening of the blood-brain barrier (BBB) to allow targeted delivery of therapeutic substances into the brain and thus the noninvasive delivery of gene vectors for CNS treatment. We have previously demonstrated that a separated gene-carrying liposome and MBs administration plus FUS exposure can deliver genes into the brain, with the successful expression of the reporter gene and glial cell line-derived neurotrophic factor (GDNF) gene. In this study, we further modify the delivery system by conjugating gene-carrying liposomes with MBs to improve the GDNF gene-delivery efficiency, and to verify the possibility of using this system to perform treatment in the 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced animal disease model. FUS-BBB opening was verified by contrast-enhanced MRI, and GFP gene expression was verified via in vivo imaging system (IVIS). Western blots as well as enzyme-linked immunosorbent assay (ELISA) were conducted to measure protein expression, and immunohistochemistry (IHC) was conducted to test the Tyrosine hydroxylase (TH)-neuron distribution. Dopamine (DA) and its metabolites as well as dopamine active transporter (DAT) were quantitatively analyzed to show dopaminergic neuronal dopamine secretion/activity/metabolism. Motor performance was evaluated by rotarod test weekly. Results demonstrated that the LpDNA-MBs (gene-liposome-MBs) complexes successfully serve as gene carrier and BBB-opening catalyst, and outperformed the separated LpDNA/MBs administration both in terms of gene delivery and expression. TH-positive IHC and measurement of DA and its metabolites DOPAC and HVA confirmed improved neuronal function, and the proposed system also provided the best neuroprotective effect to retard the progression of motor-related behavioral abnormalities. Immunoblotting and histological staining further confirmed the expression of reporter genes in

  6. Low perfusion index affects the difference in glucose level between capillary and venous blood

    Directory of Open Access Journals (Sweden)

    Acar N

    2014-11-01

    Full Text Available Nurdan Acar,1 Hamit Ozcelik,1 Arif Alper Cevik,1 Engin Ozakin,1 Goknur Yorulmaz,2 Nur Kebapci,2 Ugur Bilge,3 Muzaffer Bilgin4 1Emergency Department, 2Endocrinology Department, 3Family Medicine Department, 4Biostatistics Department, Medical School, Eskisehir Osmangazi University, Eskisehir, Turkey Aim: In emergency cases, finger stick testing is primarily used to check the blood glucose value of patients since it takes longer to obtain the venous value. In critical patients, under conditions that cause an increase in metabolic state and level of stress, there occurs considerable difference in glucose levels between capillary and venous measurements. This study aimed to investigate the comparability of capillary and venous glucose values, according to the perfusion index level obtained with the Masimo Radical-7® device, in critical patients aged 18 years and over.Method: We conducted this prospective and observational study in the emergency department of the Eskisehir Osmangazi University hospital between November 3, 2008 and February 2, 2009.Results: The blood glucose of 300 critical patients was checked by finger stick in the emergency unit. The participants with normal vital signs had perfusion index between 0 and 5; the results obtained by the two methods were more consistent for perfusion index values of 6 and over. The results were most consistent in aged participants with normal vital sign findings and low perfusion index and in young patients with high perfusion index. In the cases where at least one of the vital signs was abnormal, the glucose values obtained by the two methods were more consistent when the perfusion index was 6 or over. In this group, independently from the perfusion index value, the consistency was higher in younger patients compared with aged patients.Conclusion: In the emergency department, perfusion index value measured by Masimo Radical-7 and capillary blood glucose levels can serve in blood sugar management in

  7. Clinical and Experimental Study of Effects of Rhubarb on Gastrointestinal Blood Flow Perfusion in Critical Illness

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective: To investigate the effect of rhubarb on gastrointestinal blood perfusion in critical illness and hemorrhagic shocked rats.Methods: Clinical Study: Sixty-four septic patients, who suffered from stress ulcer, were treated with rhubarb at a dose of 25 mg/kg. Twenty-five non-septic patients were taken as control. The gastrointestinal perfusion was evaluated by intramural pH (pHi). Animal study: SD rats were anesthetized with intraperitoneal sodium pentobarbital at a dose of 20 mg/kg. Blood-letting were performed in the animals. Blood pressure reduced to 5.32 kPa and maintained for 120 mins. They were resuscitated at the end of shock by reinfusing all of the shed blood. The rats were randomly divided into four groups: Normal control, shock group, therapeutic group (shocked rats were treated with 50 mg/kg rhubarb at the end of shock) and rhubarb group (normal rats were treated with rhubarb). Laser Doppler was applied to estimate the gastrointestinal blood perfusion. Results: Clinical Study: The gastrointestinal pHi in septic patients was much lower than that in the control, whereas rhubarb could obviously elevate gastrointestinal pHi (P<0.001). In addition, rhubarb also had good effect on gastric hemorrhage caused by stress ulcer. Animal Study: Although the shocked rats were resuscitated completely, their gastrointestinal blood perfusion was much lower than that in the control. Rhubarb could significantly improve the blood perfusion in gastrointestinal mucosa and mesentery (P<0.01). Furthermore, rhubarb also increase the gastrointestinal perfusion in normal rats. Conclusion: Rhubarb could improve gastrointestinal blood perfusion in critical illness and shocked rats.

  8. Development and performance evaluation of Time-over-Threshold based digital PET (TODPET2) scanner using SiPM/Ce:GAGG-arrays for non-invasive measurement of blood RI concentrations

    Science.gov (United States)

    Yoshino, M.; Kamada, K.; Shoji, Y.; Yoshikawa, A.; Shimazoe, K.; Lipovec, A.; Takahashi, H.; Fujiwara, K.; Takahashi, M.; Momose, T.; Ito, S.; Tsutsumi, K.; Endo, T.; Sato, H.; Usuki, Y.

    2017-02-01

    We developed Time-over-Threshold based digital PET (TODPET2) tomograph using silicon photomultipliers (SiPM) arrays coupled with pixelized Ce:Gd3(Ga, Al)5O12 (Ce:GAGG) scintillators dedicated for non-invasive measurement of blood RI concentrations. The detector consists of 1.57 × 1.57 mm2 SiPM chips and 1.6 × 1.6 × 15 mm3 Ce:GAGG scintillators arranged on a 12 × 12 channel, both working as individual readout systems. After the development of the detector, we fabricated the PET gantry composed of 8 pieces of SiPM/Ce:GAGG detector array which signals were sent to the current-comparing type time-over-threshold (TOT) ASIC for individual readout of pixels. The PET scanner which we developed has 25 mm axial field-of-view (FOV) and 60 mm transaxial FOV. The spatial resolution reconstructed with maximum likelihood estimation method (MLEM) is 0.98 mm (FWHM) at the center of FOV. The sensitivity of the system is measured to be 1.31% using 22Na point source. Finally, timing response to changes in RI concentration was also measured using 5 mm diameter syringe injected with several concentrations of 18FDG.

  9. Effects of vascular elastosis on uterine blood flow and perfusion in anesthetized mares.

    Science.gov (United States)

    Esteller-Vico, A; Liu, I K M; Vaughan, B; Steffey, E P; Brosnan, R J

    2015-04-01

    In the uterus of the mare, data obtained using transrectal Doppler ultrasonography indicate that uterine blood flow (UBF) is dynamic and changes throughout the estrous cycle. Degenerative lesions in the uterus are associated with subfertility and infertility. Among these lesions, vascular elastosis has been reported in aged, multiparous, and infertile mares. Angiosis of the uterine vasculature could potentially compromise UBF. The objectives of this experiment are to determine levels of UBF and perfusion of reproductively healthy mares and compare them to levels of subfertile/infertile mares affected by uterine vascular elastosis. Twenty mares were classified on the basis of degree of vascular degeneration and stage of cycle. A fluorescent microsphere technique was used to measure reproductive organ perfusion, where microspheres were injected into the left ventricle of the heart and became trapped in capillary beds in proportion to blood flow and tissue perfusion. The reproductive tract was removed, sectioned, and the fluorescent intensity evaluated to measure blood flow and perfusion. Additionally, full-thickness samples of the uterine wall were examined postmortem to further assess the degree of vascular degeneration in all layers of uterine wall. The mean value of uterine perfusion for the control mares during estrus (n = 5) was higher (P perfusion was not different (P > 0.05) during estrus (n = 5) and diestrus (n = 5); 5.9 and 7.2 mL/min/100g, respectively. Uterine perfusion in subfertile/infertile mares affected by elastosis was lower than that of control mares during both estrus (P perfusion between the control and elastosis groups indicate that elastosis of the uterine vasculature is associated with decreased uterine perfusion during both phases of the estrous cycle. In the uterus, a compromise in UBF could have implications in endometrial glandular development, postbreeding endometritis, uterine clearance, development of the conceptus, and

  10. Numerical simulation of blood flow in femoral perfusion: comparison between side-armed femoral artery perfusion and direct femoral artery perfusion.

    Science.gov (United States)

    Kitamura, Shingo; Shirota, Minori; Fukuda, Wakako; Inamura, Takao; Fukuda, Ikuo

    2016-12-01

    Computational numerical analysis was performed to elucidate the flow dynamics of femoral artery perfusion. Numerical simulation of blood flow was performed from the right femoral artery in an aortic model. An incompressible Navier-Stokes equation and continuity equation were solved using computed flow dynamics software. Three different perfusion models were analyzed: a 4.0-mm cannula (outer diameter 15 French size), a 5.2-mm cannula (18 French size) and an 8-mm prosthetic graft. The cannula was inserted parallel to the femoral artery, while the graft was anastomosed perpendicular to the femoral artery. Shear stress was highest with the 4-mm cannula (172 Pa) followed by the graft (127 Pa) and the 5.2-mm cannula (99 Pa). The cannula exit velocity was high, even when the 5.2-mm cannula was used. Although side-armed perfusion with an 8-mm graft generated a high shear stress area near the point of anastomosis, flow velocity at the external iliac artery was decreased. The jet speed decreased due to the Coanda effect caused by the recirculation behind sudden expansion of diameter, and the flow velocity maintains a constant speed after the reattachment length of the flow. This study showed that iliac artery shear stress was lower with the 5.2-mm cannula than with the 4-mm cannula when used for femoral perfusion. Side-armed graft perfusion generates a high shear stress area around the anastomotic site, but flow velocity in the iliac artery is slower in the graft model than in the 5.2-mm cannula model.

  11. SPECT Myocardial Blood Flow Quantitation Concludes Equivocal Myocardial Perfusion SPECT Studies to Increase Diagnostic Benefits.

    Science.gov (United States)

    Chen, Lung-Ching; Lin, Chih-Yuan; Chen, Ing-Jou; Ku, Chi-Tai; Chen, Yen-Kung; Hsu, Bailing

    2016-01-01

    Recently, myocardial blood flow quantitation with dynamic SPECT/CT has been reported to enhance the detection of coronary artery disease in human. This advance has created important clinical applications to coronary artery disease diagnosis and management for areas where myocardial perfusion PET tracers are not available. We present 2 clinical cases that undergone a combined test of 1-day rest/dipyridamole-stress dynamic SPECT and ECG-gated myocardial perfusion SPECT scans using an integrated imaging protocol and demonstrate that flow parameters are capable to conclude equivocal myocardial perfusion SPECT studies, therefore increasing diagnostic benefits to add value in making clinical decisions.

  12. A low-cost, small volume circuit for autologous blood normothermic perfusion of rabbit organs.

    Science.gov (United States)

    Worner, Murray; Poore, Samuel; Tilkorn, Daniel; Lokmic, Zerina; Penington, Anthony J

    2014-04-01

    We have designed a laboratory extracorporeal normothermic blood perfusion system for whole organs (e.g., kidney) that achieves pulsatile flow, low levels of hemolysis, and a blood priming volume of 60 mL or less. Using this uniquely designed extracorporeal circuit, we have achieved perfusion of two isolated ex vivo constructs. In the first experiment, we successfully perfused a rabbit epigastric flap based on the femoral vessels. In the second experiment, we were able to perfuse the isolated rabbit kidney for 48 h (range for all kidneys was 12-48 h) with excellent urine output, normal arterial blood gasses at 24 h, and normal ex vivo kidney histology at the conclusion of the experiments. These parameters have not been achieved before with any known or previously published laboratory extracorporeal circuits. The study has implications for prolonged organ perfusion prior to transplantation and for tissue engineering of vascularized tissues, such as by the perfusion of decellularized organs.

  13. Non invasive evaluation of the coronary atherosclerosis illness in patients with silent ischemia: utility of the SPECT of myocardial perfusion. Electric, angiographic and image correlation; Valoracion no invasiva de la enfermedad ateroesclerosa coronaria en pacientes con isquemia silente: utilidad del SPECT de perfusion miocardica. Correlacion electrica, angiografica y de imagen

    Energy Technology Data Exchange (ETDEWEB)

    Puente B, A.; Roffe G, F.; Aceves C, J.; Gomez A, E. [Hospital Centro Medico Nacional 20 de Noviembre, ISSSTE, Mexico D.F. (Mexico)

    2005-07-01

    The objective of the work was to determine the utility of the SPECT (Single Photon Emission Computerized Tomography) of myocardial perfusion for the ischemia detection in asymptomatic patients with Coronary Atherosclerosis Illness. It was concluded that the SPECT of myocardial perfusion has a high sensitivity (97%) for the silent ischemia diagnosis.

  14. Skin Blood Perfusion and Cellular Response to Insertion of Insulin Pen Needles With Different Diameters

    DEFF Research Database (Denmark)

    Præstmark, Kezia Ann; Stallknecht, Bente Merete; Bo Jensen, Casper

    2014-01-01

    Today most research on pen needle design revolves around pain perception statements through clinical trials, but these are both costly, timely, and require high sample sizes. The purpose of this study was to test if tissue damage, caused by different types of needles, can be assessed by evaluating...... skin blood perfusion response around needle insertion sites. Three common sized pen needles of 28G, 30G, and 32G as well as hooked 32G needles, were inserted into the neck skin of pigs and then removed. Laser Speckle Contrast Analysis was used to measure skin blood perfusion for 20 minutes after......, but there was a trend of an increased response with increasing needle diameter. Skin blood perfusion response to pen needle insertions rank according to needle diameter, and the tissue response caused by hooked 32G needles corresponds to that of 28G needles. The relation between needle diameter and trauma when...

  15. Pattern of brain blood perfusion in tinnitus patients using technetium-99m SPECT imaging

    Directory of Open Access Journals (Sweden)

    Saeid Mahmoudian

    2012-01-01

    Full Text Available Background and Purpose: Tinnitus is associated with an increased activity in central auditory system as demonstrated by neuroimaging studies. Brain perfusion scanning using single photon emission computed tomography (SPECT was done to understand the pattern of brain blood perfusion of tinnitus subjects and find the areas which are mostly abnormal in these patients. Materials and Methods: A number of 122 patients with tinnitus were enrolled to this cross-sectional study. They underwent SPECT and magnetic resonance imaging (MRI of brain, and the images were fused to find the regions with abnormal perfusion. Results: SPECT scan results were abnormal in 101 patients (83%. Most patients had bilateral abnormal perfusion (N = 65, 53.3%, and most subjects had abnormality in middle-temporal gyrus (N = 83, 68% and temporoparietal cortex (N = 46, 37.7%. Patients with multifocal involvement had the least mean age than other 2 groups (patients with no abnormality and unifocal abnormality (P value = 0.045. Conclusions: Brain blood perfusion pattern differs in patient with tinnitus than others. These patients have brain perfusion abnormality, mostly in auditory gyrus (middle temporal and associative cortex (temporoparietal cortex. Multifocal abnormalities might be due to more cognitive and emotional brain centers involvement due to tinnitus or more stress and anxiety of tinnitus in the young patients.

  16. Consistenyc of perioperative invasive blood pressure m easurement with non-invasive blood pressure measurement for lower extremities in patients undergoing general anesth esia%全麻手术患者围术期下肢有创血压与无创血压的一致性分析

    Institute of Scientific and Technical Information of China (English)

    衣晓卓; 李天发; 王红霞; 夏豪; 周期

    2016-01-01

    目的:分析全麻手术患者围术期下肢有创血压与无创血压的一致性。方法选取行神经外科手术的患者30例,均行静脉全身麻醉。术中及术后同时监测患者脚踝部的无创血压及同侧足背动脉的有创血压,对两种血压进行比较。结果在手术开始后0~4 h内,有创测量脚踝部的收缩压及舒张压测量值均高于无创测量(P<0.05),在手术开始后4~16 h,两种测量方法的收缩压及舒张压测量值比较,差异无统计学意义(P>0.05)。两种测量方法对全麻手术患者围术期下肢收缩压及舒张压的监测一致性均好(Kappa=0.70,0.79)。结论监测全麻手术患者围术期下肢无创血压和有创血压一致性好,但仍存在一定差异,在手术中要根据患者的具体情况选取血压的测量方式。%Objective To analyze the consistency of perioperative invasive blood pressure measurement with non -invasive blood pressure measurement for lower extremities in patients undergoing general anesthesia .Methods Thirty patients receiving neurosurgery were enrolled and underwent intravenous general anesthesia .The non-invasive blood pressure of the ankle and the invasive blood pressure of the ipsilateral dorsal artery were monitored in all cases during surgery and after surgery .The results of the two blood pressure measurements were compared.Results Within 0-4 hours after the surgery starting,the systolic blood pressure and diastolic blood pressure of the ankle measured by the invasive method were higher than those measured by the non -invasive method(P<0.05).Within 4-16 hours after the surgery starting ,there was no significant difference in the systolic blood pressure or diastolic blood pressure between two methods .For patientsundergoing general anesthesia ,good consistency existed between the two measurements for perioperative systolic blood pressure and diastolic blood pressure of lower extremities (Kappa

  17. Three-dimensional optical micro-angiography maps directional blood perfusion deep within microcirculation tissue beds in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ruikang K [Department of Biomedical Engineering, Oregon Health and Science University, Portland, OR 97237 (United States)

    2007-12-07

    Optical micro-angiography (OMAG) is a recently developed method of imaging localized blood perfusion at capillary level resolution within microcirculatory beds. This paper reports that the OMAG is capable of directional blood perfusion mapping in vivo. This is achieved simply by translating the mirror located in the reference arm back and forth while 3D imaging is performed. The mirror which moves toward the incident beam gives the blood perfusion that flows away from the beam direction and vice versa. The approach is experimentally demonstrated by imaging of a flow phantom and then cerebro-vascular perfusion of a live mouse with cranium intact.

  18. Non-invasive ventilation for cystic fibrosis.

    Science.gov (United States)

    Moran, Fidelma; Bradley, Judy M; Piper, Amanda J

    2017-02-20

    Non-invasive ventilation may be a means to temporarily reverse or slow the progression of respiratory failure in cystic fibrosis by providing ventilatory support and avoiding tracheal intubation. Using non-invasive ventilation, in the appropriate situation or individuals, can improve lung mechanics through increasing airflow and gas exchange and decreasing the work of breathing. Non-invasive ventilation thus acts as an external respiratory muscle. This is an update of a previously published review. To compare the effect of non-invasive ventilation versus no non-invasive ventilation in people with cystic fibrosis for airway clearance, during sleep and during exercise. We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register comprising references identified from comprehensive electronic database searches, handsearching relevant journals and abstract books of conference proceedings. We searched the reference lists of each trial for additional publications possibly containing other trials.Most recent search: 08 August 2016. Randomised controlled trials comparing a form of pressure preset or volume preset non-invasive ventilation to no non-invasive ventilation used for airway clearance or during sleep or exercise in people with acute or chronic respiratory failure in cystic fibrosis. Three reviewers independently assessed trials for inclusion criteria and methodological quality, and extracted data. Ten trials met the inclusion criteria with a total of 191 participants. Seven trials evaluated single treatment sessions, one evaluated a two-week intervention, one evaluated a six-week intervention and one a three-month intervention. It is only possible to blind trials of airway clearance and overnight ventilatory support to the outcome assessors. In most of the trials we judged there was an unclear risk of bias with regards to blinding due to inadequate descriptions. The six-week trial was the only one judged to have a low risk of bias for all

  19. Multi-detector CT perfusion

    Directory of Open Access Journals (Sweden)

    Ashraf M. Enite

    2016-09-01

    Conclusion: CTP is a promising non-invasive technique assessing the efficacy, predicting early response to local treatment therapies and monitoring tumor recurrence. It assesses the degree of post therapy tumor perfusion especially the degree of arterialization.

  20. Validation of non-invasive haemodynamic methods in patients with liver disease

    DEFF Research Database (Denmark)

    Brittain, Jane M; Busk, Troels M; Møller, Søren

    2017-01-01

    , SBP, DBP and HR were measured non-invasively and by femoral artery catheterization. CO was measured non-invasively and by indicator dilution technique. The non-invasive pressure monitoring was considered acceptable with a bias (accuracy) and a SD (precision) not exceeding 5 and 8 mmHg, respectively......Patients with advanced cirrhosis often present a hyperdynamic circulation characterized by a decrease in systolic and diastolic blood pressure (SBP and DBP), and an increase in heart rate (HR) and cardiac output (CO). Accurate assessment of the altered circulation can be performed invasively......; however, due to the disadvantages of this approach, non-invasive methods are warranted. The purpose of this study was to compare continuous non-invasive measurements of haemodynamic variables by the Finometer and the Task Force Monitor with simultaneous invasive measurements. In 25 patients with cirrhosis...

  1. Subtracted dynamic MR perfusion source images (sMRP-SI) provide collateral blood flow assessment in MCA occlusions and predict tissue fate

    Energy Technology Data Exchange (ETDEWEB)

    Villringer, Kersten; Serrano-Sandoval, Rafael; Galinovic, Ivana; Ostwaldt, Ann-Christin; Brunecker, Peter; Fiebach, Jochen B. [Charite-Universitaetsmedizin, Academic Neuroradiology, Center for Stroke Research (CSB), Berlin (Germany); Grittner, Ulrike [Charite, Universitaetsmedizin Berlin, Center for Stroke Research, Berlin (Germany); Charite, Department for Biostatistics and Clinical Epidemiology, Berlin (Germany); Schneider, Alice [Charite, Universitaetsmedizin Berlin, Center for Stroke Research, Berlin (Germany); Rocco, Andrea [Charite, Department of Neurology and Center for Stroke Research, Berlin (Germany)

    2016-05-15

    Collateral blood flow is accepted as a predictive factor of tissue fate in ischemic stroke. Thus, we aimed to evaluate a new method derived from MR perfusion source images to assess collateral flow in patients with ICA/MCA occlusions. A total of 132 patients of the prospective 1000+ study were examined. MR perfusion source images were assessed according to Δimg{sub n} = img{sub n} + 1 - img{sub n} - 1 using the five-grade Higashida collateral flow rating system. Higashida scores were correlated to mismatch (MM) volume, mismatch ratio, day 6 FLAIR lesion volumes and day 90 mRS. Patients with Higashida scores 3 and 4 had significantly lower admission NIHSS, smaller FLAIR day 6 lesion volumes (p < 0.001) and higher rates of better long-term outcome (mRS 0-2, p = 0.002). There was a linear trend for the association of Higashida grade 1 (p = 0.002) and 2 (p = 0.001) with unfavourable outcome (day 90 mRS 3-6), but no significant association was found for MM volume, MM ratio and day 90 mRS. Inter-rater agreement was 0.58 (95 % CI 0.43-0.73) on day 1, 0.70 (95 % CI 0.58-0.81) on day 2. sMRP-SI Higashida score offers a non-invasive collateral vessel and tissue perfusion assessment of ischemic tissue. The predictive value of Higashida rating proved superior to MM with regard to day 90 mRS. (orig.)

  2. Blood-brain barrier permeability imaging using perfusion computed tomography

    Directory of Open Access Journals (Sweden)

    Avsenik Jernej

    2015-06-01

    Full Text Available Background. The blood-brain barrier represents the selective diffusion barrier at the level of the cerebral microvascular endothelium. Other functions of blood-brain barrier include transport, signaling and osmoregulation. Endothelial cells interact with surrounding astrocytes, pericytes and neurons. These interactions are crucial to the development, structural integrity and function of the cerebral microvascular endothelium. Dysfunctional blood-brain barrier has been associated with pathologies such as acute stroke, tumors, inflammatory and neurodegenerative diseases.

  3. Blood-brain barrier permeability imaging using perfusion computed tomography

    OpenAIRE

    Avsenik Jernej; Bisdas Sotirios; Popovic Katarina Surlan

    2015-01-01

    Background. The blood-brain barrier represents the selective diffusion barrier at the level of the cerebral microvascular endothelium. Other functions of blood-brain barrier include transport, signaling and osmoregulation. Endothelial cells interact with surrounding astrocytes, pericytes and neurons. These interactions are crucial to the development, structural integrity and function of the cerebral microvascular endothelium. Dysfunctional blood-brain barrier has been associated with patholog...

  4. Dynamic Perfusion CT Assessment of the Blood-Brain Barrier Permeability : First Pass versus Delayed Acquisition

    NARCIS (Netherlands)

    Dankbaar, J. W.; Hom, J.; Schneider, T.; Cheng, S. -C.; Lau, B. C.; van der Schaaf, I.; Virmani, S.; Pohlman, S.; Dillon, W. P.; Wintermark, M.

    2008-01-01

    BACKGROUND AND PURPOSE: The Patlak model has been applied to first-pass perfusion CT (PCT) data to extract information on blood-brain barrier permeability (BBBP) to predict hemorrhagic transformation in patients with acute stroke. However, the Patlak model was originally described for the delayed st

  5. Dynamic Perfusion CT Assessment of the Blood-Brain Barrier Permeability : First Pass versus Delayed Acquisition

    NARCIS (Netherlands)

    Dankbaar, J. W.; Hom, J.; Schneider, T.; Cheng, S. -C.; Lau, B. C.; van der Schaaf, I.; Virmani, S.; Pohlman, S.; Dillon, W. P.; Wintermark, M.

    2008-01-01

    BACKGROUND AND PURPOSE: The Patlak model has been applied to first-pass perfusion CT (PCT) data to extract information on blood-brain barrier permeability (BBBP) to predict hemorrhagic transformation in patients with acute stroke. However, the Patlak model was originally described for the delayed st

  6. LASER-DOPPLER VELOCIMETRY AND MONTE-CARLO SIMULATIONS ON MODELS FOR BLOOD PERFUSION IN TISSUE

    NARCIS (Netherlands)

    DEMUL, FFM; KOELINK, MH; KOK, ML; HARMSMA, PJ; GREVE, J; GRAAFF, R; AARNOUDSE, JG

    1995-01-01

    Laser Doppler flow measurements and Monte Carlo simulations on small blood perfusion flow models at 780 nm are presented and compared. The dimensions of the optical sample volume are investigated as functions of the distance of the laser to the detector and as functions of the angle of penetration o

  7. The relationship between red blood cell deformability metrics and perfusion of an artificial microvascular network.

    Science.gov (United States)

    Sosa, Jose M; Nielsen, Nathan D; Vignes, Seth M; Chen, Tanya G; Shevkoplyas, Sergey S

    2014-01-01

    The ability of red blood cells (RBC) to undergo a wide range of deformations while traversing the microvasculature is crucial for adequate perfusion. Interpretation of RBC deformability measurements performed in vitro in the context of microvascular perfusion has been notoriously difficult. This study compares the measurements of RBC deformability performed using micropore filtration and ektacytometry with the RBC ability to perfuse an artificial microvascular network (AMVN). Human RBCs were collected from healthy consenting volunteers, leukoreduced, washed and exposed to graded concentrations (0-0.08%) of glutaraldehyde (a non-specific protein cross-linker) and diamide (a spectrin-specific protein cross-linker) to impair the deformability of RBCs. Samples comprising cells with two different levels of deformability were created by adding non-deformable RBCs (hardened by exposure to 0.08% glutaraldehyde) to the sample of normal healthy RBCs. Ektacytometry indicated a nearly linear decline in RBC deformability with increasing glutaraldehyde concentration. Micropore filtration showed a significant reduction only for concentrations of glutaraldehyde higher than 0.04%. Neither micropore filtration nor ektacytometry measurements could accurately predict the AMVN perfusion. Treatment with diamide reduced RBC deformability as indicated by ektacytometry, but had no significant effect on either micropore filtration or the AMVN perfusion. Both micropore filtration and ektacytometry showed a linear decline in effective RBC deformability with increasing fraction of non-deformable RBCs in the sample. The corresponding decline in the AMVN perfusion plateaued above 50%, reflecting the innate ability of blood flow in the microvasculature to bypass occluded capillaries. Our results suggest that in vitro measurements of RBC deformability performed using either micropore filtration or ektacytometry may not represent the ability of same RBCs to perfuse microvascular networks. Further

  8. The Relationship Between Some Complete Blood Count Parameters and Myocardial Perfusion: A Scintigraphic Approach.

    Science.gov (United States)

    Ozdemir, Semra; Barutcu, Ahmet; Gazi, Emine; Tan, Yusuf Ziya; Turkon, Hakan

    2015-01-01

    Recent studies have shown that there is a relationship between some inflammatory and biochemical markers derived from complete blood count (CBC) such as neutrophil/lymphocyte (N/L) ratio, platelet/lymphocyte (P/L) ratio, platelet distribution width (PDW), red blood cell distribution width (RDW), and coronary artery disease (CAD). The aim of this study was to determine N/L ratio, P/L ratio, PDW values, and RDW values, which are associated with myocardial perfusion in patients diagnosed with CAD. This study included 262 patients (149 with myocardial ischemia/infarction and 113 with normal myocardial perfusion) undergoing myocardial perfusion scintigraphy (MPS) with CBC within 90 days of MPS. Myocardial perfusion parameters such as summed stress score and summed difference score (SDS) were compared with N/L ratio, P/L ratio, PDW values, and RDW values. Neutrophil counts and N/L ratios were significantly higher in patients diagnosed with myocardial ischemia and/or infarct. However, there was no statistically significant relationship between myocardial perfusion abnormalities and P/L ratio, PDW values, and RDW values. This study showed that N/L ratio is related to myocardial ischemia/infarction and correlated to left ventricular ejection fraction (LVEF).

  9. Non-invasive sensing for food reassurance.

    Science.gov (United States)

    Xiaobo, Zou; Xiaowei, Huang; Povey, Malcolm

    2016-03-01

    Consumers and governments are increasingly interested in the safety, authenticity and quality of food commodities. This has driven attention towards non-invasive sensing techniques used for rapid analyzing these commodities. This paper provides an overview of the state of the art in, and available alternatives for, food assurance based on non-invasive sensing techniques. The main food quality traits of interest using non-invasive sensing techniques are sensory characteristics, chemical composition, physicochemical properties, health-protecting properties, nutritional characteristics and safety. A wide range of non-invasive sensing techniques, from optical, acoustical, electrical, to nuclear magnetic, X-ray, biosensor, microwave and terahertz, are organized according to physical principle. Some of these techniques are now in a period of transition between experimental and applied utilization and several sensors and instruments are reviewed. With continued innovation and attention to key challenges, such non-invasive sensors and biosensors are expected to open up new exciting avenues in the field of portable and wearable wireless sensing devices and connecting with mobile networks, thus finding considerable use in a wide range of food assurance applications. The need for an appropriate regulatory framework is emphasized which acts to exclude unwanted components in foods and includes needed components, with sensors as part of a reassurance framework supporting regulation and food chain management. The integration of these sensor modalities into a single technological and commercial platform offers an opportunity for a paradigm shift in food reassurance.

  10. Evaluating perfusion of thoracic spinal cord blood using CEUS during thoracic spinal stenosis decompression surgery.

    Science.gov (United States)

    Ling, J; Jinrui, W; Ligang, C; Wen, C; Xiaoguang, L; Liang, J

    2015-01-13

    Study design:A clinical study in human spinal cord.Objectives:To evaluate changes in spinal cord blood perfusion in patients with thoracic spinal stenosis using contrast-enhanced ultrasonography and to semiquantitatively analyze blood perfusion changes in compressed spinal cord before and after ventral decompression.Setting:Ultrasound department of a university hospital.Methods:Twelve patients with confirmed thoracic spinal stenosis who needed decompression surgery participated. They underwent an intravenous injection of a contrast agent before and after ventral decompression. Quantitative analysis software (Philips Healthcare, Bothell, WA, USA) was used to perform time-intensity curve (TIC) analysis. The enhanced intensity (ΔI), rise time (ΔT) and slope of the TIC (β) were separately calculated; t-tests of the independent samples were performed on the indicators.Results:The TICs showed no significant differences between compressed spinal cord and normal spinal cord in ΔT, enhanced ΔI and β (P= 0.46, P=0.23 and P=0.16, respectively). After ventral decompression, ΔI of the originally compressed spinal cord increased substantially (P= 0.04) compared with ΔI of the normal spinal cord; however, the ΔT and β showed no significant differences (P= 0.18 and P=0.09, respectively). Comparison of the blood perfusion parameters (that is, ΔT and ΔI) of the compressed spinal cords before and after ventral decompression showed no significant differences (P=0.14 and P=0.12, respectively), but β showed significant difference (P=0.02).Conclusion:Contrast-enhanced ultrasonography can dynamically display spinal cord blood perfusion. The characteristics of blood perfusion can be semiquantitatively analyzed using a software technique.Spinal Cord advance online publication, 13 January 2015; doi:10.1038/sc.2014.213.

  11. Non-invasive matrices in human biomonitoring: a review.

    Science.gov (United States)

    Esteban, Marta; Castaño, Argelia

    2009-02-01

    Humans and other living organisms are exposed to a variety of chemical pollutants that are released into the environment as a consequence of anthropogenic activities. Environmental pollutants are incorporated into the organism by different routes and can then be stored and distributed in different tissues, which leads to an internal concentration that can induce different alterations, adverse effects and/or diseases. Control measures should be taken to avoid these effects and human biomonitoring is a very useful tool that can contribute to this aim. Human biomonitoring uses different matrices to measure the target chemicals depending on the chemical, the amount of matrix necessary for the analysis and the detection limit (LOD) of the analytical technique. Blood is the ideal matrix for most chemicals due to its contact with the whole organism and its equilibrium with organs and tissues where chemicals are stored. However, it has an important disadvantage of being an invasive matrix. The development of new methodology and modern analytical techniques has allowed the use of other matrices that are less or non-invasive, such as saliva, urine, meconium, nails, hair, and semen or breast milk. The presence of a chemical in these matrices reflects an exposure, but correlations between levels in non-invasive matrices and blood must be established to ensure that these levels are related to the total body burden. The development of new biomarkers that are measurable in these matrices will improve non-invasive biomonitoring. This paper reviews studies that measure Cd, Pb, Hg, polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polycyclic aromatic hydrocarbons (PAHs), polybrominated diphenyl ethers (PBDEs), organochlorine pesticides and phthalates in non-invasive matrices, the most used techniques for measurements and what alternative techniques are available.

  12. Abolished ventilation and perfusion of lung caused by blood clot in the left main bronchus

    DEFF Research Database (Denmark)

    Afzelius, P; Bergmann, A; Henriksen, J H

    2015-01-01

    /Q) scintigraphy with single-photon emission CT (SPECT)/CT. V/Q SPECT/CT demonstrated abolished ventilation due to obstruction of the left main bronchus and markedly reduced perfusion of the entire left lung, a condition that was completely reversed after removal of a blood clot. We present the first pictorially......It is generally assumed that the lungs possess arterial autoregulation associated with bronchial obstruction. A patient with pneumonia and congestive heart failure unexpectedly developed frequent haemoptysis. High-resolution CT and diagnostic CT were performed as well as ventilation/perfusion (V...

  13. The Evaluation of Light Conditions Influence and Corrections upon Doppler Blood Perfusion Imagining

    Directory of Open Access Journals (Sweden)

    Jan Kubicek

    2016-01-01

    Full Text Available The paper deals with theoretical and experimental research of the ambient light influence upon the measuring reliability of the perfusion maps by the laser Doppler method using the device PeriScan PIM 3. The main applicable result of the analysis is a set of recommendations for the standardization, the improving of reliability and the compactness of the blood perfusion measuring in the clinical practise. The improvement of examination brings more accurate results and contributes to the optimization of diagnostic process and therapy.

  14. Effect of blood flow on muscle lactate release studied in perfused rat hindlimb

    DEFF Research Database (Denmark)

    Pilegaard, H; Bangsbo, Jens; Henningsen, P

    1995-01-01

    The influence of blood flow on muscle lactate and H+ release as well as muscle glyconeogenesis was studied in the perfused rat hindlimb. After 2 min of supramaximal stimulation the perfusate flow rate was 7 (F7), 12 (F12), or 18 (F18) ml/min for 30 min. Perfusate samples were drawn frequently...... and muscle samples were obtained before stimulation, immediately after stimulation, and at 3, 10, and 30 min of recovery from soleus, white gastrocnemius (WG) and red gastrocnemius. During the first 5 min of recovery lactate release was 35-39% lower (P F7 than in F12 and F18...... but with no differences in total release during recovery. In F7 the concentration of lactate was higher (P F7 than in F12 and F18. The difference...

  15. Effect of treppe on isovolumic function in the isolated blood-perfused mouse heart.

    Science.gov (United States)

    Brooks, W W; Apstein, C S

    1996-08-01

    The effects of treppe on left ventricular function in the isolated mouse heart perfused with physiological buffer or with erythrocyte-rich buffer were compared. Left ventricular systolic and diastolic pressures were measured in the isovolumically contracting (balloon in the left ventricle) mouse hearts. Hearts were isolated from 12 adult Swiss-Webster mice and perfused at constant pressure (approximately 85 mmHg) via the aorta. Perfusate consisted of non-recirculating oxygenated Krebs-Henseleit (KH) solution without or with washed cow red blood cells at a hematocrit of 20% (KH-RBC20). The measured ionized calcium concentration of the perfusates were adjusted to 2.2 mmol/l and the temperature held constant at 37 degrees C. Left ventricular systolic pressure, its derivative and diastolic pressures were recorded via a pressure transducer attached to a small latex balloon which was placed in the left ventricle through a left atrial incision. The balloon volume was adjusted to achieve an end-diastolic pressure of 4-8 mmHg. Left ventricular (LV) developed pressure averaged 111 +/- 4 (mean +/- S.E.M.) with KH alone and 108 +/- 4 mmHg with KH-RBC20 while the coronary flows were 3.1 +/- 0.18 and 0.95 +/- 0.15 ml/min respectively. In both KH solution alone and KH-RBC20, developed pressure remained relatively stable from 3 to 5 Hz while +/- dp/dt increased approximately 10% above values observed at 3 Hz. During KH perfusion with increasing stimulation rates, left ventricular pressure and +/- dP/dt, to a lesser extent, decreased while end-diastolic pressure markedly increased at stimulation rates higher than 5 Hz. However, KH-RBC20 perfusion prevented the marked increase in diastolic pressure with increasing stimulation rates (from 5 to 10 Hz). No significant difference in left ventricular developed pressure or +/dP/dt response to treppe were in evidence between groups. These results demonstrate that diastolic function of the isovolumically contracting mouse heart is sensitive

  16. Arterial and portal venous liver perfusion using selective spin labelling MRI

    Energy Technology Data Exchange (ETDEWEB)

    Schalkx, Hanke J.; Petersen, Esben T.; Veldhuis, Wouter B.; Leeuwen, Maarten S. van; Bosch, Maurice A.A.J. van den [University Medical Center Utrecht, Department of Radiology, HP E.01.132, Postbus 85500, Utrecht (Netherlands); Peters, Nicky H.G.M. [Atrium Medical Center Parkstad, Department of Radiology, Heerlen (Netherlands); Pluim, Josien P.W.; Stralen, Marijn van [University Medical Center Utrecht, Image Sciences Institute, Utrecht (Netherlands)

    2015-06-01

    To investigate the feasibility of selective arterial and portal venous liver perfusion imaging with spin labelling (SL) MRI, allowing separate labelling of each blood supply. The portal venous perfusion was assessed with a pulsed EPISTAR technique and the arterial perfusion with a pseudo-continuous sequence. To explore precision and reproducibility, portal venous and arterial perfusion were separately quantified in 12 healthy volunteers pre- and postprandially (before and after meal intake). In a subgroup of 6 volunteers, the accuracy of the absolute portal perfusion and its relative postprandial change were compared with MRI flow measurements of the portal vein. The portal venous perfusion significantly increased from 63 ± 22 ml/100g/min preprandially to 132 ± 42 ml/100g/min postprandially. The arterial perfusion was lower with 35 ± 22 preprandially and 22 ± 30 ml/100g/min postprandially. The pre- and postprandial portal perfusion using SL correlated well with flow-based perfusion (r{sup 2} = 0.71). Moreover, postprandial perfusion change correlated well between SL- and flow-based quantification (r{sup 2} = 0.77). The SL results are in range with literature values. Selective spin labelling MRI of the portal venous and arterial blood supply successfully quantified liver perfusion. This non-invasive technique provides specific arterial and portal venous perfusion imaging and could benefit clinical settings where contrast agents are contraindicated. (orig.)

  17. Non-Invasive In Vivo Characterization of Breast Tumors Using Photon Migration Spectroscopy

    Directory of Open Access Journals (Sweden)

    Bruce J. Tromberg

    2000-01-01

    Full Text Available Frequency-domain photon migration (FDPM is a noninvasive optical technique that utilizes intensity-modulated, near-infrared (NIR light to quantitatively measure optical properties in thick tissues. Optical properties (absorption, μa, and scattering, μs′, parameters derived from FDPM measurements can be used to construct low-resolution (0.5 to 1 cm functional images of tissue hemoglobin (total, oxy-, and deoxyforms, oxygen saturation, blood volume fraction, water content, fat content and cellular structure. Unlike conventional NIR transillumination, FDPM enables quantitative analysis of tissue absorption and scattering parameters in a single non-invasive measurement. The unique functional information provided by FDPM makes it well-suited to characterizing tumors in thick tissues. In order to test the sensitivity of FDPM for cancer diagnosis, we have initiated clinical studies to quantitatively determine normal and malignant breast tissue optical and physiological properties in human subjects. Measurements are performed using a non-invasive, multi-wavelength, diode-laser FDPM device optimized for clinical studies. Results show that ductal carcinomas (invasive and in situ and benign fibroadenomas exhibit 1.25 to 3-fold higher absorption than normal breast tissue. Within this group, absorption is greatest for measurements obtained from sites of invasive cancer. Optical scattering is approximately 20% greater in pre-menopausal versus post-menopausal subjects due to differences in gland/cell proliferation and collagen/fat content. Spatial variations in tissue scattering reveal the loss of differentiation associated with breast disease progression. Overall, the metabolic demands of hormonal stimulation and tumor growth are detectable using photon migration techniques. Measurements provide quantitative optical property values that reflect changes in tissue perfusion, oxygen consumption, and cell/matrix development.

  18. Applicability of non-invasively collected matrices for human biomonitoring

    Directory of Open Access Journals (Sweden)

    Nickmilder Marc

    2009-03-01

    Full Text Available Abstract With its inclusion under Action 3 in the Environment and Health Action Plan 2004–2010 of the European Commission, human biomonitoring is currently receiving an increasing amount of attention from the scientific community as a tool to better quantify human exposure to, and health effects of, environmental stressors. Despite the policy support, however, there are still several issues that restrict the routine application of human biomonitoring data in environmental health impact assessment. One of the main issues is the obvious need to routinely collect human samples for large-scale surveys. Particularly the collection of invasive samples from susceptible populations may suffer from ethical and practical limitations. Children, pregnant women, elderly, or chronically-ill people are among those that would benefit the most from non-invasive, repeated or routine sampling. Therefore, the use of non-invasively collected matrices for human biomonitoring should be promoted as an ethically appropriate, cost-efficient and toxicologically relevant alternative for many biomarkers that are currently determined in invasively collected matrices. This review illustrates that several non-invasively collected matrices are widely used that can be an valuable addition to, or alternative for, invasively collected matrices such as peripheral blood sampling. Moreover, a well-informed choice of matrix can provide an added value for human biomonitoring, as different non-invasively collected matrices can offer opportunities to study additional aspects of exposure to and effects from environmental contaminants, such as repeated sampling, historical overview of exposure, mother-child transfer of substances, or monitoring of substances with short biological half-lives.

  19. The blood perfusion and NADH/FAD content combined analysis in patients with diabetes foot

    Science.gov (United States)

    Dremin, Victor V.; Sidorov, Victor V.; Krupatkin, Alexander I.; Galstyan, Gagik R.; Novikova, Irina N.; Zherebtsova, Angelina I.; Zherebtsov, Evgeny A.; Dunaev, Andrey V.; Abdulvapova, Zera N.; Litvinova, Karina S.; Rafailov, Ilya E.; Sokolovski, Sergei G.; Rafailov, Edik U.

    2016-03-01

    Skin blood microcirculation and the metabolism activity of tissue were examined on the patients with type 2 diabetes. Laser Doppler flowmetry (LDF) with 1064 nm laser light source and fluorescence spectroscopy (FS) with excitation light of 365 nm and 450 nm have been used to monitor the blood perfusion and the content of coenzymes NADH and FAD. Concluding, the proposed combined LDF and tissue FS approach allows to identify the significant violations in the blood microcirculation and metabolic activity for type 2 diabetes patients.

  20. Photoacoustic imaging of blood perfusion in tissue and phantoms

    Science.gov (United States)

    Pilatou, Magdalena C.; Kolkman, Roy G. M.; Hondebrink, Erwin; Bolt, Rene A.; de Mul, Frits F. M.

    2001-06-01

    To localize and monitor the blood content in tissue we developed a very sensitive photo-acoustical detector. PVDF has been used as piezo-electric material. In this detector also fibers for the illumination of the sample are integrated. Resolution is about 20 (m in depth and about 50-100 m laterally). We use 532 nm light. We will show how photoacoustics can be used for measuring the thickness of tissue above bone. We will also report measurements on tissue phantoms: e.g. a vessel delta from the epigastric artery branching of a Wistar rat, filled with an artificial blood-resembling absorber. The measurements have been carried out on phantoms containing vessels at several depths. Signal processing was enhanced by Fourier processing of the data.

  1. Non invasive prenatal diagnosis: analysis of circulating fetal DNA and cells in maternal blood El diagnóstico prenatal no invasor: análisis de células y ADN fetal circulantes en la sangre materna

    Directory of Open Access Journals (Sweden)

    Diana Cecilia Jaramillo Posada

    2009-11-01

    Full Text Available

    Prenatal non invasive diagnosis by means of analyses of foetal DNA or cells circulating in maternal blood is one of the most promising areas of obstetrics. Among maternal diseases that could be diagnosed by these methods, or whose behaviour could be predicted, are preeclampsia, growth restriction and preterm labour. Some foetal conditions that could be detected are sex, chromosomal anomalies and single-gene defects. However, these are complex and expensive techniques that are not regularly performed in health care institutions. With this review we intend to provide the readers with up to date information on the main techniques available for the study of circulating foetal cells and DNA, and on their possible clinical applications. The review was based on a search for journals indexed up to 2008 in Pubmed, Scielo and Latindex. Especially relevant articles were chosen by the authors.

    El diagnóstico prenatal temprano y no invasor por medio del análisis de células o ADN fetales circulantes en la sangre materna es un área prometedora de la obstetricia moderna. Entre las enfermedades que se pueden diagnosticar o cuyo comportamiento es posible predecir por estos métodos se encuentran la preeclampsia, la restricción del crecimiento intrauterino y el parto pretérmino. Algunas condiciones fetales que podrían detectarse son el sexo, ciertas anomalías cromosómicas y los defectos de un solo gen. Sin

  2. A Surface Heat Disturbance Method for Measuring Local TIssue Blood Perfusion Rate

    Institute of Scientific and Technical Information of China (English)

    PengJianshu; TianYongquan

    1996-01-01

    A non-damage method for measuring local tissue blood perfusion rate by surface heat disturbance and its two special embodiments for realizing this measurement are presented in this paper,In the derivation of mathematical model,the Pennes equation is used,and two parameters which are very diffcult to be known-the arterial blood temperature Ta and the metabolic heat generation rate qm,have been eliminated.So if has provided a feasible basis for application.In this paper,the performance and the adaptable condition of the measurement method and its structure peculiarities are discussed over a wide variety of parameters.Moreover,the effectiveness of the measurement method has been demonstrated by means of the quantitative measurement of tissue in vitro,the comparative measurement of animal under artificial perfusion and the dependence measurement in human body.

  3. Displaying perfusion MRI images as color intensity projections

    CERN Document Server

    Hoefnagels, Friso; Sanchez, Ester; Lagerwaard, Frank J

    2007-01-01

    Dynamic susceptibility-weighted contrast-enhanced (DSC) MRI or perfusion-MRI plays an important role in the non-invasive assessment of tumor vascularity. However, the large number of images provided by the method makes display and interpretation of the results challenging. Current practice is to display the perfusion information as relative cerebral blood volume maps (rCBV). Color intensity projections (CIPs) provides a simple, intuitive display of the perfusion-MRI data so that regional perfusion characteristics are intrinsically integrated into the anatomy structure the T2 images. The ease of use and quick calculation time of CIPs should allow it to be easily integrated into current analysis and interpretation pipelines.

  4. Phthalate monoesters in perfusate from a dual placenta perfusion system, the placenta tissue and umbilical cord blood

    DEFF Research Database (Denmark)

    Mose, Tina; Mortensen, Gerda K; Hedegaard, Morten;

    2006-01-01

    Fetal exposure to phthalates may be associated with adverse reproductive effects, including cryptorchidism and decreased semen quality. Information about human placental transfer is needed to qualify the hypotheses. A dual recirculating placenta perfusion system to monitor concentrations of eight...... phthalate monoesters in fetal and maternal perfusates was established. In addition to perfusate background measures of phthalate monoesters, the concentrations in umbilical cord plasma and placenta tissue were measured. Monomethyl phthalate (mMP), monoethyl phthalate (mEP), monobutyl phthalate (m...

  5. Hepatic Blood Perfusion Estimated by Dynamic Contrast-Enhanced Computed Tomography in Pigs Limitations of the Slope Method

    Science.gov (United States)

    Winterdahl, Michael; Sørensen, Michael; Keiding, Susanne; Mortensen, Frank V.; Alstrup, Aage K. O.; Hansen, Søren B.; Munk, Ole L.

    2012-01-01

    Objective To determine whether dynamic contrast-enhanced computed tomography (DCE-CT) and the slope method can provide absolute measures of hepatic blood perfusion from hepatic artery (HA) and portal vein (PV) at experimentally varied blood flow rates. Materials and Methods Ten anesthetized 40-kg pigs underwent DCE-CT during periods of normocapnia (normal flow), hypocapnia (decreased flow), and hypercapnia (increased flow), which was induced by adjusting the ventilation. Reference blood flows in HA and PV were measured continuously by surgically-placed ultrasound transit-time flowmeters. For each capnic condition, the DCE-CT estimated absolute hepatic blood perfusion from HA and PV were calculated using the slope method and compared with flowmeter based absolute measurements of hepatic perfusions and relative errors were analyzed. Results The relative errors (mean±SEM) of the DCE-CT based perfusion estimates were −21±23% for HA and 81±31% for PV (normocapnia), 9±23% for HA and 92±42% for PV (hypocapnia), and 64±28% for HA and −2±20% for PV (hypercapnia). The mean relative errors for HA were not significantly different from zero during hypo- and normocapnia, and the DCE-CT slope method could detect relative changes in HA perfusion between scans. Infusion of contrast agent led to significantly increased hepatic blood perfusion, which biased the PV perfusion estimates. Conclusions Using the DCE-CT slope method, HA perfusion estimates were accurate at low and normal flow rates whereas PV perfusion estimates were inaccurate and imprecise. At high flow rate, both HA perfusion estimates were significantly biased. PMID:22836307

  6. Effect of hemodialysis combined blood perfusion on micro inflammation and nutrition status of diabetic nephropathy patients

    Institute of Scientific and Technical Information of China (English)

    Jin-Lin Xie; Qin-Qi Nie; Xia-Fei Li

    2015-01-01

    Objective:To study the effect of hemodialysis combined blood perfusion on micro inflammation and nutrition status of diabetic nephropathy patients.Methods: 118 cases of diabetic nephropathy patients received treatment in our hospital from December 2012 to December 2014 were chose for study and randomly divided into two groups. Observation group received hemodialysis combined blood perfusion, while control group received pure hemodialysis therapy. Then nutrition status indexes, biochemical indexes and inflammation response degrees were compared.Results:(1) nutrition status indexes: compared with control group, serum Hb and Alb levels of observation group showed increasing trend, MAC and MAMC showed ncreasing trend; (2) biochemical indexes: compared with control group, serum mRNA levels of IGF-1β,PA, TRF, RBP of observation group showed increasing trend; (3) inflammation response degrees: compared with control group, serum IL-17, IL-22, IL-1β, TGF-β1, SAA levels of observation group showed decreased trend.Conclusion: hemodialysis combined blood perfusion treatment can effectively reduce inflammation in patients with diabetic nephropathy and improve general nutritional status.

  7. Improved Perfusion MR Imaging Assessment of Intracerebral Tumor Blood Volume and Antiangiogenic Therapy Efficacy in a Rat Model with Ferumoxytol

    OpenAIRE

    Gahramanov, Seymur; Muldoon, Leslie L; Li, Xin; Neuwelt, Edward A.

    2011-01-01

    Our findings suggest that, at perfusion MR imaging, more consistent estimations of relative cerebral blood volume are provided with ferumoxytol than with gadolinium-based contrast agents regardless of the permeability of the tumor vasculature.

  8. Anastomotic leakage in rectal cancer surgery: The role of blood perfusion

    Institute of Scientific and Technical Information of China (English)

    Martin; Ruteg?rd; J?rgen; Ruteg?rd

    2015-01-01

    Anastomotic leakage after anterior resection for rectal cancer remains a common and often devastating complication. Preoperative risk factors for anastomotic leakage have been studied extensively and are used for patient selection, especially whether to perform a diverting stoma or not. From the current literature,data suggest that perfusion in the rectal stump rather than in the colonic limb may be more important for the integrity of the colorectal anastomosis. Moreover, available research suggests that the mid and upper rectum is considerably more vascularized than the lower part, in which the posterior compartment seems most vulnerable. These data fit neatly with the observation that anastomotic leaks are far more frequent in patients undergoing total compared to partial mesorectal excision, and also that most leaks occur dorsally. Clinical judgment has been shown to ineffectively assess anastomotic viability, while promising methods to measure blood perfusion are evolving. Much interest has recently been turned to near-infrared light technology, enhanced with fluorescent agents, which enables intraoperative perfusion assessment. Preliminary data are promising, but large-scale controlled trials are lacking. With maturation of such technology, perfusion measurements may in the future inform the surgeon whether anastomoses are at risk. In high colorectal anastomoses, anastomotic revision might be feasible, while a diverting stoma could be fashioned selectively instead of routinely for low anastomoses.

  9. [Changes in palmar skin blood flow, perfusion index and temperature during endoscopic thoracic sympathectomy].

    Science.gov (United States)

    Asano, Maiko; Tanaka, Motoshige; Kusaka, Hitomi; Sakai, Masato; Minami, Toshiaki

    2010-12-01

    In endoscopic thoracic sympathectomy (ETS), it is required to perform accurate cautery of the sympathetic trunk. Monitoring of palmar skin blood flow and temperature has been used to assess the efficacy of ETS. This study investigated whether Perfusion Index (PI) is useful in assessing palmar skin blood flow and temperature in ETS. We studied 5 patients (1 man, 4 women) with palmar hyperhidrosis who had undergone a total of 10 ETS procedures. We measured skin blood flow, temperature and PI during ETS and evaluated the results. Significant correlations were found between increases in skin blood flow and PI after ETS in cases with the palmar skin temperature just before ETS of below 35 degrees C. In these cases, we can substitute increases in PI with increases in skin blood flow during ETS.

  10. Non-invasive imaging of microcirculation: a technology review

    Directory of Open Access Journals (Sweden)

    Eriksson S

    2014-12-01

    Full Text Available Sam Eriksson,1,2 Jan Nilsson,1,2 Christian Sturesson1,2 1Department of Surgery, Clinical Sciences Lund, Lund University, 2Skåne University Hospital, Lund, Sweden Abstract: Microcirculation plays a crucial role in physiological processes of tissue oxygenation and nutritional exchange. Measurement of microcirculation can be applied on many organs in various pathologies. In this paper we aim to review the technique of non-invasive methods for imaging of the microcirculation. Methods covered are: videomicroscopy techniques, laser Doppler perfusion imaging, and laser speckle contrast imaging. Videomicroscopy techniques, such as orthogonal polarization spectral imaging and sidestream dark-field imaging, provide a plentitude of information and offer direct visualization of the microcirculation but have the major drawback that they may give pressure artifacts. Both laser Doppler perfusion imaging and laser speckle contrast imaging allow non-contact measurements but have the disadvantage of their sensitivity to motion artifacts and that they are confined to relative measurement comparisons. Ideal would be a non-contact videomicroscopy method with fully automatic analysis software. Keywords: laser speckle contrast imaging, sidestream dark-field, orthogonal polarization spectral imaging, laser Dopplerimaging

  11. [Non-invasive assessment of liver fibrosis].

    Science.gov (United States)

    Cohen-Ezra, Oranit; Ben-Ari, Ziv

    2015-03-01

    Chronic liver diseases represent a major public health problem, accounting for significant morbidity and mortality worldwide. Prognosis and management of chronic liver diseases depend on the amount of liver fibrosis. Liver biopsy has long remained the gold standard for assessment of liver fibrosis. Liver biopsy is an invasive procedure with associated morbidity, it is rarely the cause for mortality, and has a few limitations. During the past two decades, in an attempt to overcome the limitations of liver biopsy, non-invasive methods for the evaluation of liver fibrosis have been developed, mainly in the field of viral hepatitis. This review will focus on different methods available for non-invasive evaluation of liver fibrosis including a biological approach which quantifies serum levels of biomarkers of fibrosis and physical techniques which measure liver stiffness by transient elastography, ultrasound or magnetic resonance based elastography, their accuracy, advantages and disadvantages.

  12. Non-invasive Mapping of Cardiac Arrhythmias.

    Science.gov (United States)

    Shah, Ashok; Hocini, Meleze; Haissaguerre, Michel; Jaïs, Pierre

    2015-08-01

    Since more than 100 years, 12-lead electrocardiography (ECG) is the standard-of-care tool, which involves measuring electrical potentials from limited sites on the body surface to diagnose cardiac disorder, its possible mechanism, and the likely site of origin. Several decades of research has led to the development of a 252-lead ECG and computed tomography (CT) scan-based three-dimensional electro-imaging modality to non-invasively map abnormal cardiac rhythms including fibrillation. These maps provide guidance towards ablative therapy and thereby help advance the management of complex heart rhythm disorders. Here, we describe the clinical experience obtained using non-invasive technique in mapping the electrical disorder and guide the catheter ablation of atrial arrhythmias (premature atrial beat, atrial tachycardia, atrial fibrillation), ventricular arrhythmias (premature ventricular beats), and ventricular pre-excitation (Wolff-Parkinson-White syndrome).

  13. Ultrasonic non invasive techniques for microbiological instrumentation

    Science.gov (United States)

    Elvira, L.; Sierra, C.; Galán, B.; Resa, P.

    2010-01-01

    Non invasive techniques based on ultrasounds have advantageous features to study, characterize and monitor microbiological and enzymatic reactions. These processes may change the sound speed, viscosity or particle distribution size of the medium where they take place, which makes possible their analysis using ultrasonic techniques. In this work, two different systems for the analysis of microbiological liquid media based on ultrasounds are presented. In first place, an industrial application based on an ultrasonic monitoring technique for microbiological growth detection in milk is shown. Such a system may improve the quality control strategies in food production factories, being able to decrease the time required to detect possible contaminations in packed products. Secondly, a study about the growing of the Escherichia coli DH5 α in different conditions is presented. It is shown that the use of ultrasonic non invasive characterization techniques in combination with other conventional measurements like optical density provides complementary information about the metabolism of these bacteria.

  14. Investigation of source-detector separation optimization for an implantable perfusion and oxygenation sensor for liver blood vessels

    Energy Technology Data Exchange (ETDEWEB)

    Baba, Justin S [ORNL; Akl, Tony [Texas A& M University; Cote, Gerard L. [Texas A& M University; Wilson, Mark A. [University of Pittsburgh School of Medicine, Pittsburgh PA; Ericson, Milton Nance [ORNL

    2011-01-01

    An implanted system is being developed to monitor transplanted liver health during the critical 7-10 day period posttransplantation. The unit will monitor organ perfusion and oxygen consumption using optically-based probes placed on both the inflow and outflow blood vessels, and on the liver parenchymal surface. Sensing probes are based on a 3- wavelength LED source and a photodiode detector. Sample diffuse reflectance is measured at 735, 805, and 940 nm. To ascertain optimal source-to-photodetector spacing for perfusion measurement in blood vessels, an ex vivo study was conducted. In this work, a dye mixture simulating 80% blood oxygen saturation was developed and perfused through excised porcine arteries while collecting data for various preset probe source-to-photodetector spacings. The results from this study demonstrate a decrease in the optical signal with decreasing LED drive current and a reduction in perfusion index signal with increasing probe spacing. They also reveal a 2- to 4-mm optimal range for blood vessel perfusion probe source-to-photodetector spacing that allows for sufficient perfusion signal modulation depth with maximized signal to noise ratio (SNR). These findings are currently being applied to guide electronic configuration and probe placement for in vivo liver perfusion porcine model studies.

  15. Laser speckle contrast imaging of skin blood perfusion responses induced by laser coagulation

    Energy Technology Data Exchange (ETDEWEB)

    Ogami, M; Kulkarni, R; Wang, H; Reif, R; Wang, R K [University of Washington, Department of Bioengineering, Seattle, Washington 98195 (United States)

    2014-08-31

    We report application of laser speckle contrast imaging (LSCI), i.e., a fast imaging technique utilising backscattered light to distinguish such moving objects as red blood cells from such stationary objects as surrounding tissue, to localise skin injury. This imaging technique provides detailed information about the acute perfusion response after a blood vessel is occluded. In this study, a mouse ear model is used and pulsed laser coagulation serves as the method of occlusion. We have found that the downstream blood vessels lacked blood flow due to occlusion at the target site immediately after injury. Relative flow changes in nearby collaterals and anastomotic vessels have been approximated based on differences in intensity in the nearby collaterals and anastomoses. We have also estimated the density of the affected downstream vessels. Laser speckle contrast imaging is shown to be used for highresolution and fast-speed imaging for the skin microvasculature. It also allows direct visualisation of the blood perfusion response to injury, which may provide novel insights to the field of cutaneous wound healing. (laser biophotonics)

  16. Laser speckle contrast imaging of skin blood perfusion responses induced by laser coagulation

    Science.gov (United States)

    Ogami, M.; Kulkarni, R.; Wang, H.; Reif, R.; Wang, R. K.

    2014-08-01

    We report application of laser speckle contrast imaging (LSCI), i.e., a fast imaging technique utilising backscattered light to distinguish such moving objects as red blood cells from such stationary objects as surrounding tissue, to localise skin injury. This imaging technique provides detailed information about the acute perfusion response after a blood vessel is occluded. In this study, a mouse ear model is used and pulsed laser coagulation serves as the method of occlusion. We have found that the downstream blood vessels lacked blood flow due to occlusion at the target site immediately after injury. Relative flow changes in nearby collaterals and anastomotic vessels have been approximated based on differences in intensity in the nearby collaterals and anastomoses. We have also estimated the density of the affected downstream vessels. Laser speckle contrast imaging is shown to be used for highresolution and fast-speed imaging for the skin microvasculature. It also allows direct visualisation of the blood perfusion response to injury, which may provide novel insights to the field of cutaneous wound healing.

  17. Validation of non-invasive arterial pressure monitoring during carotid endarterectomy.

    Science.gov (United States)

    Heusdens, J F; Lof, S; Pennekamp, C W A; Specken-Welleweerd, J C; de Borst, G J; van Klei, W A; van Wolfswinkel, L; Immink, R V

    2016-09-01

    Patients undergoing carotid endarterectomy require strict arterial blood pressure (BP) control to maintain adequate cerebral perfusion. In this study we tested whether non-invasive beat-to-beat Nexfin finger BP (BPfin) can replace invasive beat-to-beat radial artery BP (BPrad) in this setting. In 25 consecutive patients (median age 71 yr) scheduled for carotid endarterectomy and receiving general anaesthesia, BPfin and BPrad were monitored simultaneously and ipsilaterally during the 30-min period surrounding carotid artery cross-clamping. Validation was guided by the standard set by the Association for the Advancement of Medical Instrumentation (AAMI), which considers a BP monitor adequate when bias (precision) is <5 (8) mm Hg, respectively. BPfin vs BPrad bias (precision) was -3.3 (10.8), 6.1 (5.7) and 3.5 (5.2) mm Hg for systolic, diastolic, and mean BP, respectively. One subject was excluded due to a poor quality BP curve. In another subject, mean BPfin overestimated mean BPrad by 13.5 mm Hg. Mean BPfin could be considered as an alternative for mean BPrad during a carotid endarterectomy, based on the AAMI criteria. In 23 of 24 patients, the use of mean BPfin would not lead to decisions to adjust mean BPrad values outside the predefined BP threshold. NCT01451294. © The Author 2016. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  18. Repeated Microsphere Delivery for Serial Measurement of Regional Blood Perfusion in the Chronically Instrumented, Conscious Canine

    Science.gov (United States)

    Bartoli, Carlo R.; Okabe, Kazunori; Akiyama, Ichiro; Coull, Brent; Godleski, John J.

    2008-01-01

    INTRODUCTION For chronic, repeated hemodynamic studies in conscious dogs, we designed and tested a chronically instrumented canine, microsphere delivery model. The goals of this study were to investigate the accuracy of repeated estimations of blood perfusion using fluorescent-labeled microspheres and to develop and validate a chronic preparation that permits consecutive estimations in the same conscious animal over an extended protocol. METHODS Via thoracotomy, 9 dogs were instrumented with left atrial appendage and aortic vascular access catheters connected to subcutaneous vascular access ports (VAPs). Four animals received 7 serial injections of 1.6 million 15μm microspheres (total: 11.2 million), and five animals received 8 serial injections of 2.25 million microspheres (total: 18 million) over the course of 11 or 18 weeks. RESULTS All catheters have remained bidirectionally patent during protocol for 14.9±0.8 (Mean±SEM) weeks. Sphere accumulation did not significantly alter global myocardial (p=0.69, p=0.25), renal (p=0.92, p=0.12), hepatic (p=0.84, p=0.32), or splenic (p=0.33, p=0.70) blood perfusion in either set of animals. CONCLUSIONS Catheters remained bidirectionally patent for months, did not interfere with the hemodynamic responses of the preparation, and allowed repeat percutaneous injection of microspheres and withdrawal of reference arterial blood from within conscious canines. Eight serial injections totaling 18 million microspheres over 18 weeks did not alter regional myocardial, hepatic, renal, or splenic blood flow. This dependable, chronic, percutaneous arterial access preparation provides a means for examining acute and long-term effects of pathophysiological, pharmaceutical, and environmental influences on regional arterial blood perfusion in conscious, large animals. PMID:17632127

  19. Longterm treatment with endothelin receptor antagonist bosentan and iloprost improves fingertip blood perfusion in systemic sclerosis.

    Science.gov (United States)

    Cutolo, Maurizio; Ruaro, Barbara; Pizzorni, Carmen; Ravera, Francesca; Smith, Vanessa; Zampogna, Giuseppe; Paolino, Sabrina; Seriolo, Bruno; Cimmino, Marco; Sulli, Alberto

    2014-05-01

    To evaluate the longterm effects of endothelin-1 (ET-1) antagonism on peripheral blood perfusion (PBP) in patients with systemic sclerosis (SSc). Twenty-six patients with SSc already receiving cyclic intravenous iloprost (ILO) for severe Raynaud phenomenon were enrolled. Thirteen patients continued the treatment for a further 3 years (ILO group) and 13 patients, because of the appearance of digital ulcers, received in addition bosentan (BOS; 125 mg twice/day) for 3 years (ILO + BOS group). Both PBP at fingertips and nailfold microangiopathy were evaluated yearly by laser Doppler flowmetry and nailfold videocapillaroscopy, respectively. A progressive significant increase of PBP was observed in the ILO + BOS group during the 3 followup years (p = 0.0007, p = 0.0002, p = 0.01, respectively). In contrast, an insignificant progressive decrease of PBP was observed in the ILO group. Difference of perfusion between the PBP evaluations at basal temperature and at 36 °C (to test capillary dilation capacity), was found progressively decreased during the 3-year followup only in the ILO group (p = 0.05, p = 0.26, p = 0.09, respectively). A progressive increase of nailfold capillary number was observed only in the ILO + BOS group after 2 and 3 years of followup (p = 0.05). Longterm treatment of SSc patients with ET-1 antagonism, in combination with ILO, seems to increase fingertip blood perfusion, as well as both capillary dilation capacity and number.

  20. Effects of Electroacupuncture Stimulation at "Zusanli" Acupoint on Hepatic NO Release and Blood Perfusion in Mice.

    Science.gov (United States)

    Wang, Shu-You; Zhang, Dong; Tang, Li-Mei; Li, Shun-Yue; Wen, Mei; Song, Xiao-Jing

    2015-01-01

    The study is to observe the influence of electroacupuncture (EA) stimulation at "Zusanli" (ST36) on the release of nitric oxide (NO) and blood perfusion (BP) in the liver and further explore whether the hepatic blood perfusion (HBP) changes were regulated by EA ST36 induced NO in nitric oxide synthase inhibited mice. The HBP change of the mice was detected by laser speckle perfusion imaging (LSPI) before and after being given interventions, and the NO in liver tissue was detected by nitric acid reductase in each group. The NO levels and HBP in the L-NAME group were significantly lower than those in the control group (P < 0.01). The NO level and HBP increase in EA group were significantly higher than those in control group (P < 0.05). The NO level in the L-NAME EA group was slightly higher than that in the L-NAME group. The HBP increase in the L-NAME EA group was not statistically significant. These results showed that EA could accelerate the synthesis of NO and thereby increase HBP via vasodilation in liver tissue.

  1. Evaluation of tumor blood flow after feeder embolization in meningiomas by arterial spin-labeling perfusion magnetic resonance imaging.

    Science.gov (United States)

    Kawaji, Hiroshi; Koizumi, Shinichiro; Sakai, Naoto; Yamasaki, Tomohiro; Hiramatsu, Hisaya; Kanoko, Yusuke; Kamiya, Mika; Yamashita, Shuhei; Takehara, Yasuo; Sakahara, Harumi; Namba, Hiroki

    2013-10-01

    Preoperative embolization changes the amount of blood flow and pattern of flow distribution in meningioma. Tumor blood flow was investigated in eight meningioma patients before and after embolization using arterial spin-labeling (ASL) perfusion imaging. Although blood flow was significantly reduced in the whole tumor after embolization, changes in flow distribution patterns varied from one case to another. The findings suggest that evaluation of post-embolization tumor blood flow by ASL perfusion imaging would be useful in the surgical planning of meningioma.

  2. Increased brainstem perfusion, but no blood-brain barrier disruption, during attacks of migraine with aura.

    Science.gov (United States)

    Hougaard, Anders; Amin, Faisal M; Christensen, Casper E; Younis, Samaira; Wolfram, Frauke; Cramer, Stig P; Larsson, Henrik B W; Ashina, Messoud

    2017-06-01

    See Moskowitz (doi:10.1093/brain/awx099) for a scientific commentary on this article.The migraine aura is characterized by transient focal cortical disturbances causing dramatic neurological symptoms that are usually followed by migraine headache. It is currently not understood how the aura symptoms are related to the headache phase of migraine. Animal studies suggest that cortical spreading depression, the likely mechanism of migraine aura, causes disruption of the blood-brain barrier and noxious stimulation of trigeminal afferents leading to activation of brainstem nuclei and triggering of migraine headache. We used the sensitive and validated technique of dynamic contrast-enhanced high-field magnetic resonance imaging to simultaneously investigate blood-brain barrier permeability and tissue perfusion in the brainstem (at the level of the lower pons), visual cortex, and brain areas of the anterior, middle and posterior circulation during spontaneous attacks of migraine with aura. Patients reported to our institution to undergo magnetic resonance imaging during the headache phase after presenting with typical visual aura. Nineteen patients were scanned during attacks and on an attack-free day. The mean time from attack onset to scanning was 7.6 h. We found increased brainstem perfusion bilaterally during migraine with aura attacks. Perfusion also increased in the visual cortex and posterior white matter following migraine aura. We found no increase in blood-brain barrier permeability in any of the investigated regions. There was no correlation between blood-brain barrier permeability, brain perfusion, and time from symptom onset to examination or pain intensity. Our findings demonstrate hyperperfusion in brainstem during the headache phase of migraine with aura, while the blood-brain barrier remains intact during attacks of migraine with aura. These data thus contradict the preclinical hypothesis of cortical spreading depression-induced blood-brain barrier

  3. A review on the non-invasive evaluation of skeletal muscle oxygenation

    Science.gov (United States)

    Halim, A. A. A.; Laili, M. H.; Aziz, N. A.; Laili, A. R.; Salikin, M. S.; Rusop, M.

    2016-07-01

    The aim of this review is to conduct a feasibility study of non-invasive evaluation in skeletal muscle oxygenation. This non-invasive evaluation could extract many information using a safe non-invasive method regarding to the oxygenation and microcirculation status in human blood muscle. This brief review highlights the progress of the application of NIRS to evaluate skeletal muscle oxygenation in various activity of human nature from the historical point of view to the present advancement. Since the discovery of non-invasive optical method during 1992, there are many non-invasive techniques uses optical properties on human subject such as near infrared spectroscopy NIRS, optical topography, functional near infrared spectroscopy fNIRS and imaging fNIRI. Furthermore, in this paper we discuss the light absorption potential (LAP) towards chromophores content inside human muscle. Modified beer lambert law was studied in order to build a better understanding toward LAP between chromophores under tissue multilayers in human muscle. This paper will describe the NIRS principle and the basis for its proposed used in skeletal muscle oxygenation. This will cover the advantages and limitation of such application. Thus, these non-invasive techniques could open other possibilities to study muscle performance diagnosis.

  4. Non-invasive quantitative pulmonary V/Q imaging using Fourier decomposition MRI at 1.5T

    Energy Technology Data Exchange (ETDEWEB)

    Kjoerstad, Aasmund; Corteville, Dominique M.R.; Zoellner, Frank G.; Schad, Lothar R. [Heidelberg Univ., Medical Faculty Mannheim (Germany). Computer Assisted Clinical Medicine; Henzler, Thomas [Heidelberg Univ., Medical Faculty Mannheim (Germany). Inst. of Clinical Radiology and Nuclear Medicine; Schmid-Bindert, Gerald [Heidelberg Univ., Medical Faculty Mannheim (Germany). Interdisciplinary Thoracic Oncology

    2015-07-01

    Techniques for quantitative pulmonary perfusion and ventilation using the Fourier Decomposition method were recently demonstrated. We combine these two techniques and show that ventilation-perfusion (V/Q) imaging is possible using only a single MR acquisition of less than thirty seconds. The Fourier Decomposition method is used in combination with two quantification techniques, which extract baselines from within the images themselves and thus allows quantification. For the perfusion, a region assumed to consist of 100% blood is utilized, while for the ventilation the zero-frequency component is used. V/Q-imaging is then done by dividing the quantified ventilation map with the quantified perfusion map. The techniques were used on ten healthy volunteers and fifteen patients diagnosed with lung cancer. A mean V/Q-ratio of 1.15±0.22 was found for the healthy volunteers and a mean V/Q-ratio of 1.93±0.83 for the non-afflicted lung in the patients. Mean V/Q-ratio in the afflicted (tumor-bearing) lung was found to be 1.61±1.06. Functional defects were clearly visible in many of the patient images, but 5 of 15 patient images had to be excluded due to artifacts or low SNR, indicating a lack of robustness. Conclusion Non-invasive, quantitative V/Q-imaging is possible using Fourier Decomposition MRI. The method requires only a single acquisition of less than 30 seconds, but robustness in patients remains an issue.

  5. Non-invasive measurement of hemoglobin: assessment of two different point-of-care technologies.

    Directory of Open Access Journals (Sweden)

    Etienne Gayat

    Full Text Available BACKGROUND: Measurement of blood hemoglobin (Hb concentration is a routine procedure. Using a non-invasive point-of-care device reduces pain and discomfort for the patient and allows time saving in patient care. The aims of the present study were to assess the concordance of Hb levels obtained non-invasively with the Pronto-7 monitor (version 2.1.9, Masimo Corporation, Irvine, USA or with the NBM-200MP monitor (Orsense, Nes Ziona, Israel and the values obtained from the usual colorimetric method using blood samples and to determine the source of discordance. METHODS AND FINDINGS: We conducted two consecutive prospective open trials enrolling patients presenting in the emergency department of a university hospital. The first was designed to assess Pronto-7™ and the second NBM-200MP™. In each study, the main outcome measure was the agreement between both methods. Independent factors associated with the bias were determined using multiple linear regression. Three hundred patients were prospectively enrolled in each study. For Pronto-7™, the absolute mean difference was 0.56 g.L(-1 (95% confidence interval [CI] 0.41 to 0.69 with an upper agreement limit at 2.94 g.L(-1 (95% CI [2.70;3.19], a lower agreement limit at -1.84 g.L(-1 (95% CI [-2.08;-1.58] and an intra-class correlation coefficient at 0.80 (95% CI [0.74;0.84]. The corresponding values for the NBM-200MP™ were 0.21 [0.02;0.39], 3.42 [3.10;3.74], -3.01 [-3.32;-2.69] and 0.69 [0.62;0.75]. Multivariate analysis showed that age and laboratory values of hemoglobin were independently associated with the bias when using Pronto-7™, while perfusion index and laboratory value of hemoglobin were independently associated with the bias when using NBM-200MP™. CONCLUSION: Despite a relatively limited bias in both cases, the large limits of agreement found in both cases render the clinical usefulness of such devices debatable. For both devices, the bias is independently and inversely associated

  6. Single photon emission CT perfusion imaging of cerebral blood flow of early syphilis patients

    Institute of Scientific and Technical Information of China (English)

    施辛; 吴锦昌; 刘增礼; 唐军; 苏玉华

    2003-01-01

    Objective To injvestigate the cerebral blood flow of patients with early syphilis. Methods 99Tcm-ECD as brain perfusion imaging agent was used in single photon emission computed tomography (SPECT) for 32 patients with early syphilis and 15 controls. Visual analyses were made on every BSPECT image. Results The 32 patients with early syphilis had general, patchy hypoperfusion of cerebral blood flow. Fourteen of the 32 patients had 48 episodes of marked patchy hypoperfusion of rCBF. The responsible areas of hypoperfusion in a patchy distribution involved the left frontal lobe (6 episodes), right frontal lobe (3), left parietal lobe (7), right parietal lobe (6), left temporal lobe (11), right temporal lobe (5), left occipital lobe (3), left basal ganglia (3), cerebellum (1), and nerve nuceus (1). No abnormality was found in the control group.Conclusions Cerebral blood flow abnormalities exist in patients with early syphilis. General patchy hypoperfusion on SPECT imaging is common.

  7. A liver perfusion model for studies of selective adherence and transient halting of portal blood leukocytes in sinusoids.

    Science.gov (United States)

    Durowicz, Sergiusz; Olszewski, Waldemar L

    2003-01-15

    Portal blood leukocytes play an important, but still poorly defined, role in the immune processes of the liver. In our previous studies, we showed that certain leukocyte subsets are selectively halted in the liver. These cells marginate in sinusoids and, together with resident Kupffer and endothelial sinusoidal cells, participate in antiviral and antitumor processes. The molecular mechanisms of margination and cooperation with resident sinusoidal cells require clarification. However, in vivo harvesting of portal blood leukocytes is associated with cumbersome cannulation of portal and hepatic veins and manipulation of the liver, causing major disturbances in splanchnic blood flow and liver blood supply, totally distorting sinusoidal blood perfusion and leukocyte margination. To overcome these difficulties, we have developed an in situ normothermic rat liver perfusion model permitting quantitative observations of blood leukocyte extraction in sinusoids. First, liver was flushed through the portal vein and the effluent leukocytes, named liver-associated leukocytes (LAL1), were collected from hepatic veins. Then, the liver was perfused for 60 min with 50 ml of blood using a semiclosed perfusion system. Upon completion of perfusion, the liver portal vasculature was flushed again to retrieve the leukocytes extracted from the perfusing blood (LAL2). These cells were characterized with respect to their phenotype and cytotoxicity. The mean leukocyte count of the washout before perfusion was 1.04+/-0.2x10(6)/g of liver tissue and 0.9+/-0.1x10(6)/g after 60 min of perfusion, indicating retention by the perfused liver, the live leukocyte extracting capacity. To further evaluate the efficiency of perfusion, FITC-labelled leukocytes were added to the perfusing leukocyte-free blood. Around 95% of the postperfusion washout LALs were FITC(+). Heat-killed leukocytes did not marginate in sinusoids. Preincubation of leukocytes with substances able to lower adhesion capacity, such as

  8. Non-invasive distress evaluation in preterm newborn infants.

    Science.gov (United States)

    Manfredi, C; Bocchi, L; Orlandi, S; Calisti, M; Spaccaterra, L; Donzelli, G P

    2008-01-01

    With the increased survival of very preterm infants, there is a growing concern for their developmental outcomes. Infant cry characteristics reflect the development and possibly the integrity of the central nervous system. In this paper, relationships between fundamental frequency (F(0)) and vocal tract resonance frequencies (F(1)-F(3)) are investigated for a set of preterm newborns, by means of a multi-purpose voice analysis tool (BioVoice), characterised by high-resolution and tracking capabilities. Also, first results about possible distress occurring during cry in preterm newborn infants, as related to the decrease of central blood oxygenation, are presented. To this aim, a recording system (Newborn Recorder) has been developed, that allows synchronised, non-invasive monitoring of blood oxygenation and audio recordings of newborn infant's cry. The method has been applied to preterm newborns at the Intensive Care Unit, A.Meyer Children Hospital, Firenze, Italy.

  9. Coupled modeling of tumour angiogenesis, tumour growth,and blood perfusion

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    This paper proposes a more realistic mathematical simulation method to investigate the dynamic process of tumour angio-genesis by fully coupling the vessel growth,tumour growth and associated blood perfusion.The tumour growth and angiogenesis are coupled by the chemical microenvironment and the cell-matrix interaction.The haemodynamic calculation is carried out on the new vasculature,and an estimation of vessel collapse is made according to the wall shear stress criterion.The results are consistent with phy...

  10. Infrared thermography: A non-invasive window into thermal physiology.

    Science.gov (United States)

    Tattersall, Glenn J

    2016-12-01

    Infrared thermography is a non-invasive technique that measures mid to long-wave infrared radiation emanating from all objects and converts this to temperature. As an imaging technique, the value of modern infrared thermography is its ability to produce a digitized image or high speed video rendering a thermal map of the scene in false colour. Since temperature is an important environmental parameter influencing animal physiology and metabolic heat production an energetically expensive process, measuring temperature and energy exchange in animals is critical to understanding physiology, especially under field conditions. As a non-contact approach, infrared thermography provides a non-invasive complement to physiological data gathering. One caveat, however, is that only surface temperatures are measured, which guides much research to those thermal events occurring at the skin and insulating regions of the body. As an imaging technique, infrared thermal imaging is also subject to certain uncertainties that require physical modelling, which is typically done via built-in software approaches. Infrared thermal imaging has enabled different insights into the comparative physiology of phenomena ranging from thermogenesis, peripheral blood flow adjustments, evaporative cooling, and to respiratory physiology. In this review, I provide background and guidelines for the use of thermal imaging, primarily aimed at field physiologists and biologists interested in thermal biology. I also discuss some of the better known approaches and discoveries revealed from using thermal imaging with the objective of encouraging more quantitative assessment.

  11. Use of Doppler ultrasound for non-invasive urodynamic diagnosis

    Directory of Open Access Journals (Sweden)

    Hideo Ozawa

    2009-01-01

    Full Text Available Objectives: A totally non-invasive transperineal urodynamic technique using Doppler ultrasonography has been developed. Methods: Since normal urine does not have blood cells, urine was thought not to produce the Doppler effects. However, basic studies confirmed that the decrease of pressure at high velocity (Bernouilli effect caused dissolved gas to form microbubbles, which are detected by Doppler ultrasonography. Subjects sat and the probe was advanced via remote control to achieve gentle contact with the perineal skin. The digital uroflow data signals and the color Doppler ultrasound video images were processed on a personal computer. The flow-velocity curves from two sites; the distal prostatic urethra just above the external sphincter (V1 and the sphincteric urethra (V2 were plotted against time. The parameters of both the pressure-flow studies and the Doppler ultrasound urodynamic studies were compared in men who had various degrees of obstruction. Results: Functional cross-sectional area at prostatic urethra (A1, calculated by Q max /V1, was lower in the group of bladder outlet obstruction (BOO vs. control group. Velocity ratio (VR, which was calculated by V1/V2, was the parameter having the best correlation with BOO index, though A1 had a similar correlation. This method is viable to diagnose the degree of BOO. Conclusions: The development of non-invasive Doppler ultrasound videourodynamics (Doppler UDS will dramatically expand the information on voiding function.

  12. Non-invasive assessment of the liver using imaging

    Science.gov (United States)

    Thorling Thompson, Camilla; Wang, Haolu; Liu, Xin; Liang, Xiaowen; Crawford, Darrell H.; Roberts, Michael S.

    2016-12-01

    Chronic liver disease causes 2,000 deaths in Australia per year and early diagnosis is crucial to avoid progression to cirrhosis and end stage liver disease. There is no ideal method to evaluate liver function. Blood tests and liver biopsies provide spot examinations and are unable to track changes in function quickly. Therefore better techniques are needed. Non-invasive imaging has the potential to extract increased information over a large sampling area, continuously tracking dynamic changes in liver function. This project aimed to study the ability of three imaging techniques, multiphoton and fluorescence lifetime imaging microscopy, infrared thermography and photoacoustic imaging, in measuring liver function. Collagen deposition was obvious in multiphoton and fluorescence lifetime imaging in fibrosis and cirrhosis and comparable to conventional histology. Infrared thermography revealed a significantly increased liver temperature in hepatocellular carcinoma. In addition, multiphoton and fluorescence lifetime imaging and photoacoustic imaging could both track uptake and excretion of indocyanine green in rat liver. These results prove that non-invasive imaging can extract crucial information about the liver continuously over time and has the potential to be translated into clinic in the assessment of liver disease.

  13. Non-Invasive Mechanic Ventilation Using in Flail Chest, Caused By Blunt Chest Trauma

    Directory of Open Access Journals (Sweden)

    Serdar Onat

    2008-01-01

    Full Text Available A 75-year-old woman admitted our faculty emergency room with shortness of breath, and chest pain after traffic accident’s second hour. She was diagnosed as bilateral multipl rib fractures, left clavicula fracture, and left flail chest by phsical and radiological examinations. She was transfered to Chest Surgery Depatment’s intensive care unit. The patient was undergone non-invasive mask mechanic ventilation support, because of the decreasing of blood oxygen saturation and increasing of arteriel blood partial carbondioxide pressure. The treatment of non-invasive mechanic ventilation was succesfull for ventilation support. With this report, we would like to attentioned that non-invasive mechanic ventilation for blunt chest trauma patients could be used succesfully and could be used instead of endotracheal invasive mechanic ventilation.

  14. Non-invasive Evaluation for Epilepsy Surgery

    Science.gov (United States)

    IWASAKI, Masaki; JIN, Kazutaka; NAKASATO, Nobukazu; TOMINAGA, Teiji

    2016-01-01

    Epilepsy surgery is aimed to remove the brain tissues that are indispensable for generating patient’s epileptic seizures. There are two purposes in the pre-operative evaluation: localization of the epileptogenic zone and localization of function. Surgery is planned to remove possible epileptogenic zone while preserving functional area. Since no single diagnostic modality is superior to others in identifying and localizing the epileptogenic zone, multiple non-invasive evaluations are performed to estimate the location of the epileptogenic zone after concordance between evaluations. Essential components of non-invasive pre-surgical evaluation of epilepsy include detailed clinical history, long-term video-electroencephalography monitoring, epilepsy-protocol magnetic resonance imaging (MRI), and neuropsychological testing. However, a significant portion of drug-resistant epilepsy is associated with no or subtle MRI lesions or with ambiguous electro-clinical signs. Additional evaluations including fluoro-deoxy glucose positron emission tomography (FDG-PET), magnetoencephalography and ictal single photon emission computed tomography can play critical roles in planning surgery. FDG-PET should be registered on three-dimensional MRI for better detection of focal cortical dysplasia. All diagnostic tools are complementary to each other in defining the epileptogenic zone, so that it is always important to reassess the data based on other results to pick up or confirm subtle abnormalities. PMID:27627857

  15. Heat-washout measurements compared to distal blood pressure and perfusion in orthopaedic patients with foot ulcers

    DEFF Research Database (Denmark)

    Midttun, M; Azad, B B S; Broholm, R

    2015-01-01

    Distal blood pressure and local skin perfusion pressure were compared to measurement of blood flow rate (BFR) measured by the heat-washout method in orthopaedic patients with and without diabetes, all with a foot ulcer in one foot, compared to healthy controls. The correlation was good between heat...

  16. Abdominal perfusion computed tomography.

    Science.gov (United States)

    Ogul, Hayri; Bayraktutan, Ummugulsum; Kizrak, Yesim; Pirimoglu, Berhan; Yuceler, Zeynep; Sagsoz, M Erdem; Yilmaz, Omer; Aydinli, Bulent; Ozturk, Gurkan; Kantarci, Mecit

    2013-02-01

    The purpose of this article is to provide an up to date review on the spectrum of applications of perfusion computed tomography (CT) in the abdomen. New imaging techniques have been developed with the objective of obtaining a structural and functional analysis of different organs. Recently, perfusion CT has aroused the interest of many researchers who are studying the applicability of imaging modalities in the evaluation of abdominal organs and diseases. Per-fusion CT enables fast, non-invasive imaging of the tumor vascular physiology. Moreover, it can act as an in vivo biomarker of tumor-related angiogenesis.

  17. Effect of Acupuncture Signal after Brachial Plexus Blockade on Cerebral Blood Perfusion and Brain Cell Function

    Institute of Scientific and Technical Information of China (English)

    任永功; 郭长春; 贾少微

    2003-01-01

    Objective: Using single photon emission computed tomography (SPECT) to observe the influence of the up-transmitting of acupuncture signal into the brain in health volunteers whose nerve trunk was blocked by anesthetics. Methods: Thirty-one healthy volunteers were divided into two groups, the control group of 20 cases, and the brachial plexus blockade (BPB) group of 11 cases, with supraclavicular BPB route adopted. With the control group 2 acupoints were randomly selected (Hegu and Quchi of both sides), while with the BPB group Hegu and Quchi of anesthetic arm side were selected. Siemens ECAM/ICON SPECT system was used to conduct brain imaging using double imaging assay before acupuncture and 99mTc-ECD imaging agent during acupuncture for cerebral perfusion. The data were quantitatively analyzed by blood functional changing rate (BFCR%) mathematics model. Results: Before acupuncture, the control and BPB groups showed insignificant change by SPECT, but after electro-acupuncture (EA), the control group displayed improved motor and sensory cortex excitability in basal nuclei, contra-lateral thalamus, parietal and frontal lobe; while BPB group was characterized with reduction of the blood perfusion and cell function of contra-lateral thalamus of anesthetized arm. The difference between the two groups was significant (P<0.01). Conclusion: (1) After BPB, the up-transmitting of the acupuncture signal via upper limb into the brain, and its strength was impaired or blocked; (2) After BPB, the effect of acupuncture on cerebral perfusion and brain cell function of contra-lateral thalamus was impaired or blocked.

  18. Blood Perfusion in Microfluidic Models of Pulmonary Capillary Networks: Role of Geometry and Hematocrit

    Science.gov (United States)

    Stauber, Hagit; Waisman, Dan; Sznitman, Josue; Technion-IIT Team; Department of Neonatology Carmel Medical Center; Faculty of Medicine-Technion IIT Collaboration

    2015-11-01

    Microfluidic platforms are increasingly used to study blood microflows at true physiological scale due to their ability to overcome manufacturing obstacle of complex anatomical morphologies, such as the organ-specific architectures of the microcirculation. In the present work, we utilize microfluidic platforms to devise in vitro models of the underlying pulmonary capillary networks (PCN), where capillary lengths and diameters are similar to the size of RBCs (~ 5-10 μm). To better understand flow characteristics and dispersion of red blood cells (RBCs) in PCNs, we have designed microfluidic models of alveolar capillary beds inspired by the seminal ``sheet flow'' model of Fung and Sobin (1969). Our microfluidic PCNs feature confined arrays of staggered pillars with diameters of ~ 5,7 and 10 μm, mimicking the dense structure of pulmonary capillary meshes. The devices are perfused with suspensions of RBCs at varying hematocrit levels under different flow rates. Whole-field velocity patterns using micro-PIV and single-cell tracking using PTV are obtained with fluorescently-labelled RBCs and discussed. Our experiments deliver a real-scale quantitative description of RBC perfusion characteristics across the pulmonary capillary microcirculation.

  19. Quantifying single microvessel permeability in isolated blood-perfused rat lung preparation.

    Science.gov (United States)

    Kandasamy, Kathirvel; Parthasarathi, Kaushik

    2014-01-01

    The isolated blood-perfused lung preparation is widely used to visualize and define signaling in single microvessels. By coupling this preparation with real time imaging, it becomes feasible to determine permeability changes in individual pulmonary microvessels. Herein we describe steps to isolate rat lungs and perfuse them with autologous blood. Then, we outline steps to infuse fluorophores or agents via a microcatheter into a small lung region. Using these procedures described, we determined permeability increases in rat lung microvessels in response to infusions of bacterial lipopolysaccharide. The data revealed that lipopolysaccharide increased fluid leak across both venular and capillary microvessel segments. Thus, this method makes it possible to compare permeability responses among vascular segments and thus, define any heterogeneity in the response. While commonly used methods to define lung permeability require postprocessing of lung tissue samples, the use of real time imaging obviates this requirement as evident from the present method. Thus, the isolated lung preparation combined with real time imaging offers several advantages over traditional methods to determine lung microvascular permeability, yet is a straightforward method to develop and implement.

  20. Lung perfusion in hemorrhagic shock of rats. The effects of resuscitation with whole blood, saline or hes 6%

    Energy Technology Data Exchange (ETDEWEB)

    Turhanoglu, S.; Kaya, S.; Kararmaz, A.; Turhanoglu, A.D. [Dicle Univ., Diyarbakir (Turkey). Medical School

    2001-12-01

    This study was undertaken to determine the effects of various resuscitation regimens on lung perfusion following resuscitation from hemorrhagic shock. Fourty male Sprague-Dawley rats (250-300 g) were used. The rats were divided randomly into four groups (n=10 for each) and were sedated with intramuscular ketamine (100 mg/kg). We measured blood pressure, rectal temperature and lung perfusion using radioscintigraphy with a technetium colloid indicator. The systolic blood pressure was decreased 75% by removing blood via v. jugularis in the first three groups and group 4 was accepted as the control group, and blood volume was not diminished. Then the first three groups were resuscitated with autologous blood containing 125 units heparine/ml in group 1, saline in group 2, and hydroxyethyl starch (HES) 6% in group 3. After the correction of hypovolemia, all animals were injected 100 Bg (0.1 cc) technetium 99m macroaggregated albumin ({sup 99m}Tc MAA) via penil vein. After injection of {sup 99m}Tc MAA, 3 minutes fixed images were detected by a {gamma} camera in posterior position at 15 minutes and 5 hours. {sup 99m}Tc MMA ''wash out'' rate in lung was determined quantitatively at 5 hours. Compared to a control group, lung perfusion was decreased significantly in groups resuscitated with saline, and HES 6% while perfusion was restored with autologous blood. We conclude that heparinized autologous blood saved lung capillary circulation in hemorrhagic shock in rats. (author)

  1. Comparable Cerebral Blood Flow in Both Hemispheres During Regional Cerebral Perfusion in Infant Aortic Arch Surgery.

    Science.gov (United States)

    Rüffer, André; Tischer, Philip; Münch, Frank; Purbojo, Ariawan; Toka, Okan; Rascher, Wolfgang; Cesnjevar, Robert Anton; Jüngert, Jörg

    2017-01-01

    Cerebral protection during aortic arch repair can be provided by regional cerebral perfusion (RCP) through the innominate artery. This study addresses the question of an adequate bilateral blood flow in both hemispheres during RCP. Fourteen infants (median age 11 days [range, 3 to 108]; median weight, 3.6 kg [range, 2.8 to 6.0 kg]) undergoing RCP (flow rate 54 to 60 mL · kg(-1) · min(-1)) were prospectively included. Using combined transfontanellar/transtemporal two- and three-dimensional power/color Doppler sonography, cerebral blood flow intensity in the main cerebral vessels was displayed. Mean time average velocities were measured with combined pulse-wave Doppler in the basilar artery, and both sides of the internal carotid, anterior, and medial cerebral arteries. In addition, bifrontal regional cerebral oximetry (rSO2) was assessed. Comparing both hemispheres, measurements were performed at target temperature (28°C) during full-flow total body perfusion (TBP) and RCP. A regular circle of Willis with near-symmetric blood flow intensity to both hemispheres was visualized in all infants during both RCP and TBP. In the left internal carotid artery, blood flow direction was mixed (retrograde, n = 5; antegrade, n = 8) during TBP and retrograde during RCP. Comparison between sides showed comparable cerebral time average velocities and rSO2, except for higher time average velocities in the right internal carotid artery (TBP p = 0.019, RCP p = 0.09). Unilateral comparison between perfusion methods revealed significantly higher rSO2 in the right hemisphere during TBP (82% ± 9%) compared with RCP (74% ± 11%, p = 0.036). Bilateral assessment of cerebral rSO2 and time average velocity in the main great cerebral vessels suggests that RCP is associated with near-symmetric blood flow intensity to both hemispheres. Further neurodevelopmental studies are necessary to verify RCP for neuroprotection during aortic arch repair. Copyright © 2017 The Society of Thoracic

  2. Tissue perfusion in neonates undergoing open-heart surgery using autologous umbilical cord blood or donor blood components.

    Science.gov (United States)

    Chasovskyi, K; Fedevych, O; McMullan, D M; Mykychak, Y; Vorobiova, G; Zhovnir, V; Yemets, I

    2015-09-01

    This study evaluates the hemoglobin-oxygen relationship and tissue perfusion during cardiopulmonary bypass (CPB) in neonates undergoing open-heart surgery using autologous umbilical cord blood or donor blood components. We compared perioperative hematocrit (Hct), fetal hemoglobin (HbF), p(50)O(2), pH, pCO(2), serum lactate, duration of mechanical ventilation and intensive care unit (ICU) length of stay in neonates undergoing open-heart surgery using autologous umbilical cord blood (Group I, N=45) or donor blood components (Group II, N=65). The groups were similar with respect to diagnosis, weight, type of procedure, duration of CPB and duration of myocardial ischemia. Mean p(50)O(2) was significantly lower in Group I during CPB (19.7 vs. 22.3 mmHg, p=0.004) and at the end of CPB (20.1 vs. 22.8 mmHg, p=0.003). Median peak lactate during CPB was higher in Group I (4.8 vs. 2.2 mmol/l, pblood, tissue oxygen delivery appears to be preserved in neonates who undergo open-heart surgery using autologous umbilical cord blood. © The Author(s) 2014.

  3. Measurement of brain perfusion, blood volume, and blood-brain barrier permeability, using dynamic contrast-enhanced T(1)-weighted MRI at 3 tesla

    DEFF Research Database (Denmark)

    Larsson, Henrik B W; Courivaud, Frédéric; Rostrup, Egill

    2009-01-01

    Assessment of vascular properties is essential to diagnosis and follow-up and basic understanding of pathogenesis in brain tumors. In this study, a procedure is presented that allows concurrent estimation of cerebral perfusion, blood volume, and blood-brain permeability from dynamic T(1)-weighted...

  4. Comparison of microsphere-equivalent blood flow (15O-water PET) and relative perfusion (99mTc-tetrofosmin SPECT) in myocardium showing metabolism-perfusion mismatch.

    Science.gov (United States)

    Schaefer, Wolfgang M; Nowak, Bernd; Kaiser, Hans-Juergen; Koch, Karl-Christian; Block, Stephan; vom Dahl, Juergen; Buell, Udalrich

    2003-01-01

    Myocardial perfusion imaging with (99m)Tc-tetrofosmin is based on the assumption of a linear correlation between myocardial blood flow (MBF) and tracer uptake. However, it is known that (99m)Tc-tetrofosmin uptake is directly related to energy-dependent transport processes, such as Na(+)/H(+) ion channel activity, as well as cellular and mitochondrial membrane potentials. Therefore, cellular alterations that affect these energy-dependent transport processes ought to influence (99m)Tc-tetrofosmin uptake independently of blood flow. Because metabolism ((18)F-FDG)-perfusion ((99m)Tc-tetrofosmin) mismatch myocardium (MPMM) reflects impaired but viable myocardium showing cellular alterations, MPMM was chosen to quantify the blood flow-independent effect of cellular alterations on (99m)Tc-tetrofosmin uptake. Therefore, we compared microsphere-equivalent MBF (MBF_micr; (15)O-water PET) and (99m)Tc-tetrofosmin uptake in MPMM and in "normal" myocardium. Forty-two patients with severe coronary artery disease, referred for myocardial viability diagnostics, were examined using (18)F-FDG PET and (99m)Tc-tetrofosmin perfusion SPECT. Relative (18)F-FDG and (99m)Tc-tetrofosmin uptake values were calculated using 18 segments per patient. Normal myocardium and MPMM myocardium were classified using a previously validated (99m)Tc-tetrofosmin SPECT/(18)F-FDG PET score. In addition, (15)O-water PET was performed to assess kinetic-modeled MBF (MBF_kin), the water-perfusable tissue fraction (PTF), and the resulting MBF_micr (MBF_kin x PTF), which is comparable to tracer uptake values. (99m)Tc-tetrofosmin uptake and MBF_micr values were calculated for all normal and MPMM segments and averaged within their respective classifications. Mean relative (99m)Tc-tetrofosmin uptake was 86% +/- 1% in normal myocardium and 56% +/- 1% in MPMM, showing a significant difference (P micr in MPMM myocardium was 0.60 +/- 0.03 mL x min(-1) x mL(-1), which did not significantly differ from normal myocardium (0

  5. Distribution of lung blood on modified bilateral Glenn shunt evaluated by Tc-99m-MAA lung perfusion scintigraphy

    Science.gov (United States)

    Si, Biao; Luan, Zhao-sheng; Wang, Tong-jian; Ning, Yan-song; Li, Na; Zhu, Meng; Liu, Zhong-min; Ding, Guang-hong; Qiao, Bin

    2016-01-01

    Abstract The aim of the present study was to determine the distribution of lung blood in a modified bilateral Glenn procedure designed in our institute with lung perfusion scintigraphy. Sixteen consecutive patients who underwent modified bilateral Glenn operation from 2011 to 2014 were enrolled in the study. The control group consisted of 7 patients who underwent bidirectional Glenn shunt. Radionuclide lung perfusion scintigraphy was performed using Tc-99m-macro aggregated albumin (MAA) in all patients. For the patients in modified bilateral Glenn group, the time at which the radioactivity accumulation peaked did not differ significantly between the right and left lung field (t = 0.608, P = 0.554). The incidence of perfusion abnormality in each lung lobe also did not differ significantly (P = 0.426 by Fisher exact test). The radioactive counts were higher in the right lung than in the left lung, but the difference was not statistically significant (t = 1.502, P = 0.157). Radioactive perfusion in the lower lung field was significantly greater than that in the upper field (t = 4.368, P lung to that in left lung was significantly lower in the modified bilateral Glenn group (t = 3.686, P = 0.002). Lung perfusion scintigraphy confirmed the benefit of the modified bilateral Glenn shunt with regard to more balanced blood perfusion in both lungs. PMID:27661042

  6. Dynamic CT myocardial perfusion imaging.

    Science.gov (United States)

    Caruso, Damiano; Eid, Marwen; Schoepf, U Joseph; Jin, Kwang Nam; Varga-Szemes, Akos; Tesche, Christian; Mangold, Stefanie; Spandorfer, Adam; Laghi, Andrea; De Cecco, Carlo N

    2016-10-01

    Non-invasive cardiac imaging has rapidly evolved during the last decade due to advancements in CT based technologies. Coronary CT angiography has been shown to reliably assess coronary anatomy and detect high risk coronary artery disease. However, this technique is limited to anatomical assessment, thus non-invasive techniques for functional assessment of the heart are necessary. CT myocardial perfusion is a new CT based technique that provides functional assessment of the myocardium and allows for a comprehensive assessment of coronary artery disease with a single modality when combined with CTA. This review aims to discuss dynamic CT myocardial perfusion as a new technique in the assessment of CAD.

  7. [Non-invasive prenatal testing: challenges for future implementation].

    Science.gov (United States)

    Henneman, Lidewij; Page-Chrisiaens, G C M L Lieve; Oepkes, Dick

    2015-01-01

    The non-invasive prenatal test (NIPT) is an accurate and safe test in which blood from the pregnant woman is used to investigate if the unborn child possibly has trisomy 21 (Down's syndrome), trisomy 18 (Edwards' syndrome) or trisomy 13 (Patau syndrome). Since April 2014 the NIPT has been available in the Netherlands as part of the TRIDENT implementation project for those in whom the first trimester combined test showed an elevated risk (> 1:200) of trisomy, or on medical indication, as an alternative to chorionic villous sampling or amniocentesis. Since the introduction of the NIPT the use of these invasive tests, which are associated with a risk of miscarriage, has fallen steeply. The NIPT may replace the combined test. Also the number of conditions that is tested for can be increased. Modification of current prenatal screening will require extensive discussion, but whatever the modification, careful counseling remains essential to facilitate pregnant women's autonomous reproductive decision making.

  8. Non-invasive prenatal testing: ethics and policy considerations.

    Science.gov (United States)

    Vanstone, Meredith; King, Carol; de Vrijer, Barbra; Nisker, Jeff

    2014-06-01

    New technologies analyzing fetal DNA in maternal blood have led to the wide commercial availability of non-invasive prenatal testing (NIPT). We present here for clinicians the ethical and policy issues related to an emerging practice option. Although NIPT presents opportunities for pregnant women, particularly women who are at increased risk of having a baby with an abnormality or who are otherwise likely to access invasive prenatal testing, NIPT brings significant ethics and policy challenges. The ethical issues include multiple aspects of informed decision-making, such as access to counselling about the possible results of the test in advance of making a decision about participation in NIPT. Policy considerations include issues related to offering and promoting a privately available medical strategy in publicly funded institutions. Ethics and policy considerations merge in NIPT with regard to sex selection and support for persons living with disabilities.

  9. Non-invasive ambient pressure estimation using non-linear ultrasound contrast agents

    DEFF Research Database (Denmark)

    Andersen, Klaus Scheldrup

    Many attempts to find a non-invasive procedure to measure the blood pressure locally in the body have been made. This dissertation focuses on the approaches which utilize highly compressible ultrasound contrast agents as ambient pressure sensors. The literature within the topic has been reviewed...

  10. Xueshuantong improves cerebral blood perfusion in elderly patients with lacunar infarction

    Institute of Scientific and Technical Information of China (English)

    Qifeng Gui; Yunmei Yang; Shihong Ying; Minming Zhang

    2013-01-01

    A total of 64 patients with acute lacunar infarction were enrolled within 24 hours of onset. The patients received conventional therapy (antiplatelet drugs and hypolipidemic drugs) alone or conventional therapy plus 450 mg Xueshuantong once a day. The main ingredient of the Xueshuantong lyophilized powder used for injection was Panax notoginseng saponins. Assessments were made at admission and at discharge using the National Institutes of Health Stroke Scale, the Activity of Daily Living and the Mini-Mental State Examination. Additionally, the relative cerebral blood flow, relative cerebral blood volume and relative mean transit time in the region of interest were calculated within 24 hours after the onset of lacunar infarction, using dynamic susceptibility contrast magnetic resonance perfusion imaging technology. Patients underwent a follow-up MRI scan after 4 weeks of treatment. There was an improvement in the Activity of Daily Living scores and a greater reduction in the scores on the National Institutes of Health Stroke Scale in the treatment group than in the control group. However, the Mini-Mental State Examination scores showed no significant differences after 4 weeks of treatment. Compared with the control group, the relative cerebral blood flow at discharge had increased and showed a greater improvement in the treatment group. Furthermore, there was a reduction in the relative mean transit time at discharge and the value was lower in the treatment group than in the control group. The experimental findings indicate that Xueshuantong treatment improves neurological deficits in elderly patients with lacunar infarction, and the mechanism may be related to increased cerebral perfusion.

  11. A non-invasive method to produce pressure ulcers of varying severity in a spinal cord-injured rat model.

    Science.gov (United States)

    Ahmed, A K; Goodwin, C R; Sarabia-Estrada, R; Lay, F; Ansari, A M; Steenbergen, C; Pang, C; Cohen, R; Born, L J; Matsangos, A E; Ng, C; Marti, G P; Abu-Bonsrah, N; Phillips, N A; Suk, I; Sciubba, D M; Harmon, J W

    2016-12-01

    Experimental study. The objective of this study was to establish a non-invasive model to produce pressure ulcers of varying severity in animals with spinal cord injury (SCI). The study was conducted at the Johns Hopkins Hospital in Baltimore, Maryland, USA. A mid-thoracic (T7-T9) left hemisection was performed on Sprague-Dawley rats. At 7 days post SCI, rats received varying degrees of pressure on the left posterior thigh region. Laser Doppler Flowmetry was used to record blood flow. Animals were killed 12 days after SCI. A cardiac puncture was performed for blood chemistry, and full-thickness tissue was harvested for histology. Doppler blood flow after SCI prior to pressure application was 237.808±16.175 PFUs at day 7. Following pressure application, there was a statistically significant decrease in blood flow in all pressure-applied groups in comparison with controls with a mean perfusion of 118.361±18.223 (Ppressure ulcer formation in the setting of a SCI. Histological analysis revealed different stages of injury corresponding to the amount of pressure the animals were exposed to with decreased blood flow immediately after the insult along with a subsequent marked increase in blood flow the next day, conducive to an ischemia-reperfusion injury (IRI) and a possible inflammatory response following tissue injury. Following ischemia and hypoxia secondary to microcirculation impairment, free radicals generate lipid peroxidation, leading to ischemic tissue damage. Future studies should be aimed at measuring free radicals during this period of increased blood flow, following tissue ischemia.

  12. Multislice Analysis of Blood Flow Values in CT Perfusion Studies of Lung Cancer

    Science.gov (United States)

    Malavasi, Silvia; Barone, Domenico; Gavelli, Giampaolo

    2017-01-01

    Objectives. Tumour heterogeneity represents a key issue in CT perfusion (CTp), where all studies are usually based on global mean or median values of perfusion maps, often computed on whole tumour. We sought to determine whether, and to what extent, such global values can be representative of tumour heterogeneity, with respect to single slices, and could be used for therapy assessment. Materials and Methods. Twelve patients with one primary non-small cell lung cancer lesion were enrolled in this study, for a total amount of 26 CTp examinations and 118 slices. Mean and median blood flow (BF) values, calculated voxel-based, were computed on each slice and the whole tumour. To measure functional heterogeneity, entropy was calculated on BF values as well. Results. Most of the slices were not represented by the global BF values computed on the whole tumour. In addition, there are a number of lesions having equivalent global BF values, but they are composed of slices having very different heterogeneity distributions, that is, entropy values. Conclusions. Global mean/median BF values of the single slices separately should be considered for clinical assessment, only if interpreted through entropy computed on BF values. The numerical equivalence between global BF values of different lesions may correspond to different clinical status, thus inducing possible errors in choice of therapy when considering global values only. PMID:28164118

  13. Cerebral blood volume imaging by flat detector computed tomography in comparison to conventional multislice perfusion CT.

    Science.gov (United States)

    Struffert, Tobias; Deuerling-Zheng, Yu; Kloska, Stephan; Engelhorn, Tobias; Boese, Jan; Zellerhoff, Michael; Schwab, Stefan; Doerfler, Arnd

    2011-04-01

    We tested the hypothesis that Flat Detector computed tomography (FD-CT) with intravenous contrast medium would allow the calculation of whole brain cerebral blood volume (CBV) mapping (FD-CBV) and would correlate with multislice Perfusion CT (PCT). Twenty five patients were investigated with FD-CBV and PCT. Correlation of the CBV maps of both techniques was carried out with measurements from six anatomical regions from both sides of the brain. Mean values of each region and the correlation coefficient were calculated. Bland-Altman analysis was performed to compare the two different imaging techniques. The image and data quality of both PCT and FD-CBV were suitable for evaluation in all patients. The mean CBV values of FD-CBV and PCT showed only minimal differences with overlapping standard deviation. The correlation coefficient was 0.79 (p < 0.01). Bland-Altman analysis showed a mean difference of -0.077 ± 0.48 ml/100 g between FD-CBV and PCT CBV measurements, indicating that FD-CBV values were only slightly lower than those of PCT. CBV mapping with intravenous contrast medium using Flat Detector CT compared favourably with multislice PCT. The ability to assess cerebral perfusion within the angiographic suite may improve the management of ischaemic stroke and evaluation of the efficacy of dedicated therapies.

  14. Quantification of blood perfusion using 3D power Doppler: an in-vitro flow phantom study

    Science.gov (United States)

    Raine-Fenning, N. J.; Ramnarine, K. V.; Nordin, N. M.; Campbell, B. K.

    2004-01-01

    Three-dimensional (3D) power Doppler data is increasingly used to assess and quantify blood flow and tissue perfusion. The objective of this study was to assess the validity of common 3D power Doppler ‘vascularity’ indices by quantification in well characterised in-vitro flow models. A computer driven gear pump was used to circulate a steady flow of a blood mimicking fluid through various well characterised flow phantoms to investigate the effect of the number of flow channels, flow rate, depth dependent tissue attenuation, blood mimic scatter particle concentration and ultrasound settings. 3D Power Doppler data were acquired with a Voluson 530D scanner and 7.5 MHz transvaginal transducer (GE Kretz). Virtual Organ Computer-aided Analysis software (VOCAL) was used to quantify the vascularisation index (VI), flow index (FI) and vascularisation-flow index (VFI). The vascular indices were affected by many factors, some intuitive and some with more complex or unexpected relationships (e.g. VI increased linearly with an increase in flow rate, blood mimic scatter particle concentration and number of flow channels, and had a complex dependence on pulse repetition frequency). Use of standardised settings and appropriate calibration are required in any attempt at relating ‘vascularity indices’ with flow.

  15. Perfusion MRI (dynamic susceptibility contrast imaging) with different measurement approaches for the evaluation of blood flow and blood volume in human gliomas

    DEFF Research Database (Denmark)

    Thomsen, H; Steffensen, E; Larsson, Elna-Marie

    2012-01-01

    technique arterial spin labelling (ASL) presently provides measurement only of cerebral blood flow (CBF), which has not been widely used in human brain tumor studies. Purpose: To assess if measurement of blood flow is comparable with measurement of blood volume in human biopsy-proven gliomas obtained by DSC......, and glioblastomas. Results: rCBF and rCBV measurements obtained with the maximum perfusion method were correlated when normalized to white matter (r ¼ 0.60) and to the cerebellum (r ¼ 0.49). Histogram analyses of rCBF and rCBV showed that mean and median values as well as skewness and peak position were correlated......-MRI using two different regions for normalization and two different measurement approaches. Material and Methods: Retrospective study of 61 patients with different types of gliomas examined with DSC perfusion MRI. Regions of interest (ROIs) were placed in tumor portions with maximum perfusion on rCBF and r...

  16. Compression-tracking photoacoustic perfusion and microvascular pressure measurements

    Science.gov (United States)

    Choi, Min; Zemp, Roger

    2017-03-01

    We propose a method to measure blood pressure of small vessels non-invasively and in-vivo: by combining PA imaging with compression US. Using this method, we have shown pressure-lumen area tracking, as well as estimation of the internal vessel pressure, located 2 mm deep in tissue. Additionally, reperfusion can be tracked by measuring the total PA signal within a region of interest (ROI) after compression has been released. The ROI is updated using cross-correlation based displacement tracking1. The change in subcutaneous perfusion rates can be seen when the temperature of the hand of a human subject drops below the normal.

  17. Effects of permanent magnets on resting skin blood perfusion in healthy persons assessed by laser Doppler flowmetry and imaging.

    Science.gov (United States)

    Mayrovitz, H N; Groseclose, E E; Markov, M; Pilla, A A

    2001-10-01

    Effects on skin blood perfusion of permanent ceramic magnets [0.1 T (1000 G) surface field], individually (disk shaped, 4 cm diameter x 1 cm thick) or in the form of a 11 x 7 in pad ( approximately 28 x 17.8 cm) with an array of 16 rectangular magnets (4.5 x 2.2 cm), were investigated in 16 female volunteers (27.4 +/- 1.7 years, range 21-48 years) using three separate protocols. In protocol A, a disk magnet was placed on the palmar surface of the hand in contact with the thenar eminence (n = 5). In protocol B, the magnet was placed on the hand dorsum overlying the thenar eminence (n = 5). In protocol C, the entire palm and fingers rested on the magnetic pad (n = 6). Magnets were in place for 36 min on one hand, and a sham was in place on the other hand. Blood perfusion was measured on the middle finger dorsum by laser Doppler flowmetry (LDF) and on the index finger by laser Doppler imaging (LDI). Perfusion measurements were simultaneously taken in sham and magnet exposed hands, before and during the entire magnet exposure interval. Magnetic field effects were tested by comparing skin blood perfusion sequences in magnet and sham exposed regions. Results showed no significant changes in either LDF or LDI perfusion at magnet or sham sites during exposure, nor were there any significant differences between sham and magnet sites for any protocol. Measurements of skin temperature at the LDF measurement sites also showed no significant change. It is concluded that in the healthy subjects studied with normal, unstressed circulation, magnets of the type and for the duration used, showed no detectible effect on skin blood perfusion in the anatomical area studied.

  18. Fade responses at neuroeffector junction to vagal stimulation in the isolated, blood-perfused dog atrium.

    Science.gov (United States)

    Furukawa, Y; Saegusa, K; Ogiwara, Y; Chiba, S

    1988-01-01

    Effects of physostigmine and of beating rate on the negative chronotropic and inotropic responses to tonic intramural parasympathetic nerve stimulation at a frequency of 5 Hz for 2 min were investigated, using the isolated, blood-perfused dog atrium which was pretreated with propranolol. The responses to stimulation reached a maximum, and then "faded" back toward the control levels during stimulation. Before physostigmine, the fade of the inotropic response was consistently observed but the fade of the chronotropic response was minimal. Both the maximum effect and the fade of the chronotropic response were augmented dose-dependently by physostigmine in spontaneously beating atria. Physostigmine increased the maximum chronotropic response to infusion of acetylcholine (ACh) but did not potentiate the fade response. These results suggest that the potentiation of the fade of the chronotropic response to stimulation after physostigmine is due to decreases in the amount of ACh at the neuroeffector junction. The maximum negative inotropic responses were dose-dependently potentiated similarly by physostigmine in isolated spontaneously beating or paced atria. The fade of the inotropic response in spontaneously beating atria was decreased along with reduction of the rate by physostigmine, whereas the fades in paced atria at 2 and 3 Hz were not changed, showing that decreases in rate during stimulation influenced the reduction of the fade. Increases in contractile force induced by infusion of CaCl2 did not alter the maximum and fade responses to stimulation in 2 Hz paced atria. The blood flow into an isolated atrium was not changed detectably during stimulation. These results suggest that the fade of the inotropic response to parasympathetic nerve stimulation is related subsidiarily to acetylcholinesterase or washout of ACh at the neuroeffector junction in isolated perfused atria.

  19. Non-Invasive, Simultaneous Quantification of Vascular Oxygenation and Glucose Uptake in Tissue

    Science.gov (United States)

    Rajaram, Narasimhan; Reesor, Andrew F.; Mulvey, Christine S.; Frees, Amy E.; Ramanujam, Nirmala

    2015-01-01

    We report the development of non-invasive, fiber-based diffuse optical spectroscopy for simultaneously quantifying vascular oxygenation (SO2) and glucose uptake in solid tumors in vivo. Glucose uptake was measured using a fluorescent glucose analog, 2-[N-(7-nitrobenz-2-oxa-1,3-diaxol-4-yl)amino]-2-deoxyglucose (2-NBDG). Quantification of label-free SO2 and 2-NBDG-fluorescence-based glucose uptake 60 minutes after administration of the tracer (2-NBDG60) was performed using computational models of light-tissue interaction. This study was carried out on normal tissue and 4T1 and 4T07 murine mammary tumor xenografts in vivo. Injection of 2-NBDG did not cause a significant change in optical measurements of SO2, demonstrating its suitability as a functional reporter of tumor glucose uptake. Correction of measured 2-NBDG-fluorescence for the effects of absorption and scattering significantly improved contrast between tumor and normal tissue. The 4T1 and 4T07 tumors showed significantly decreased SO2, and 4T1 tumors demonstrated increased 2-NBDG60 compared with normal tissue (60 minutes after the administration of 2-NBDG when perfusion-mediated effects have cleared). 2-NBDG-fluorescence was found to be highly sensitive to food deprivation-induced reduction in blood glucose levels, demonstrating that this endpoint is indeed sensitive to glycolytic demand. 2-NBDG60 was also found to be linearly related to dose, underscoring the importance of calibrating for dose when comparing across animals or experiments. 4T1 tumors demonstrated an inverse relationship between 2-NBDG60 and SO2 that was consistent with the Pasteur effect, particularly when exposed to hypoxic gas breathing. Our results illustrate the potential of optical spectroscopy to provide valuable information about the metabolic status of tumors, with important implications for cancer prognosis. PMID:25635865

  20. Non-invasive, simultaneous quantification of vascular oxygenation and glucose uptake in tissue.

    Directory of Open Access Journals (Sweden)

    Narasimhan Rajaram

    Full Text Available We report the development of non-invasive, fiber-based diffuse optical spectroscopy for simultaneously quantifying vascular oxygenation (SO2 and glucose uptake in solid tumors in vivo. Glucose uptake was measured using a fluorescent glucose analog, 2-[N-(7-nitrobenz-2-oxa-1,3-diaxol-4-ylamino]-2-deoxyglucose (2-NBDG. Quantification of label-free SO2 and 2-NBDG-fluorescence-based glucose uptake 60 minutes after administration of the tracer (2-NBDG60 was performed using computational models of light-tissue interaction. This study was carried out on normal tissue and 4T1 and 4T07 murine mammary tumor xenografts in vivo. Injection of 2-NBDG did not cause a significant change in optical measurements of SO2, demonstrating its suitability as a functional reporter of tumor glucose uptake. Correction of measured 2-NBDG-fluorescence for the effects of absorption and scattering significantly improved contrast between tumor and normal tissue. The 4T1 and 4T07 tumors showed significantly decreased SO2, and 4T1 tumors demonstrated increased 2-NBDG60 compared with normal tissue (60 minutes after the administration of 2-NBDG when perfusion-mediated effects have cleared. 2-NBDG-fluorescence was found to be highly sensitive to food deprivation-induced reduction in blood glucose levels, demonstrating that this endpoint is indeed sensitive to glycolytic demand. 2-NBDG60 was also found to be linearly related to dose, underscoring the importance of calibrating for dose when comparing across animals or experiments. 4T1 tumors demonstrated an inverse relationship between 2-NBDG60 and SO2 that was consistent with the Pasteur effect, particularly when exposed to hypoxic gas breathing. Our results illustrate the potential of optical spectroscopy to provide valuable information about the metabolic status of tumors, with important implications for cancer prognosis.

  1. Parametric investigation of heating due to magnetic fluid hyperthermia in a tumor with blood perfusion

    Energy Technology Data Exchange (ETDEWEB)

    Liangruksa, Monrudee [Department of Engineering Science and Mechanics, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061 (United States); Ganguly, Ranjan [Department of Power Engineering, Jadavpur University, Kolkata 700098 (India); Puri, Ishwar K., E-mail: ikpuri@vt.ed [Department of Engineering Science and Mechanics, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061 (United States)

    2011-03-15

    Magnetic fluid hyperthermia (MFH) is a cancer treatment that can selectively elevate the tumor temperature without significantly damaging the surrounding healthy tissue. Optimal MFH design requires a fundamental parametric investigation of the heating of soft materials by magnetic fluids. We model the problem of a spherical tumor and its surrounding healthy tissue that are heated by exciting a homogeneous dispersion of magnetic nanoparticles infused only into the tumor with an external AC magnetic field. The key dimensionless parameters influencing thermotherapy are the Peclet, Fourier, and Joule numbers. Analytical solutions for transient and steady hyperthermia provide correlations between these parameters and the portions of tumor and healthy tissue that are subjected to a threshold temperature beyond which they are damaged. Increasing the ratio of the Fourier and Joule numbers also increases the tumor temperature, but doing so can damage the healthy tissue. Higher magnetic heating is required for larger Peclet numbers due to the larger convection heat loss that occurs through blood perfusion. A comparison of the model predictions with previous experimental data for MFH applied to rabbit tumors shows good agreement. The optimal MFH conditions are identified based on two indices, the fraction I{sub T} of the tumor volume in which the local temperature is above a threshold temperature and the ratio I{sub N} of the damaged normal tissue volume to the tumor tissue volume that also lies above it. The spatial variation in the nanoparticle concentration is also considered. A Gaussian distribution provides efficacy while minimizing the possibility of generating a tumor hot spot. Varying the thermal properties of tumor and normal tissue alters I{sub T}and I{sub N} but the nature of the temperature distribution remains unchanged. - Research highlights: > Analytical model of magnetic fluid hyperthermia of tumor tissue perfused with magnetic nanoparticles that is surrounded

  2. Assessment of local changes of cerebral perfusion and blood concentration by ultrasound harmonic B-mode contrast measurement in piglet.

    NARCIS (Netherlands)

    Wijk, M.C. van; Klaessens, J.H.G.M.; Hopman, J.C.W.; Liem, K.D.; Thijssen, J.M.

    2003-01-01

    This study tested the hypothesis that changes in the blood concentration, and possibly in the perfusion, of different areas in the brain can be assessed by the use of ultrasound contrast agent (CA) and (linear) echo densitometry. The experiments were performed with piglets (n=3) under general anesth

  3. Optimal Duration of Acquisition for Dynamic Perfusion CT Assessment of Blood-Brain Barrier Permeability Using the Patlak Model

    NARCIS (Netherlands)

    Hom, J.; Dankbaar, J. W.; Schneider, T.; Cheng, S. -C.; Bredno, J.; Wintermark, M.

    2009-01-01

    BACKGROUND AND PURPOSE: A previous study demonstrated the need to use delayed acquisition rather than first-pass data for accurate blood-brain barrier permeability surface product (BBBP) calculation from perfusion CT (PCT) according to the Patlak model, but the optimal duration of the delayed acquis

  4. Carbon dioxide induced changes in cerebral blood flow and flow velocity: Role of cerebrovascular resistance and effective cerebral perfusion pressure

    NARCIS (Netherlands)

    F. Grüne (Frank); S. Kazmaier (Stephan); R.J. Stolker (Robert J.); G.H. Visser (Gerhard Henk); A. Weyland (Andreas)

    2015-01-01

    textabstractIn addition to cerebrovascular resistance (CVR) zero flow pressure (ZFP), effective cerebral perfusion pressure (CPPe) and the resistance area product (RAP) are supplemental determinants of cerebral blood flow (CBF). Until now, the interrelationship of PaCO2 -induced changes in CBF, CVR,

  5. Absolute Versus Relative Myocardial Blood Flow by Dynamic CT Myocardial Perfusion Imaging in Patients With Anatomic Coronary Artery Disease

    NARCIS (Netherlands)

    Wichmann, Julian L.; Meinel, Felix G.; Schoepf, U. Joseph; Lo, Gladys G.; Choe, Yeon Hyeon; Wang, Yining; Vliegenthart, Rozemarijn; Varga-Szemes, Akos; Muscogiuri, Giuseppe; Cannao, Paola M.; De Cecco, Carlo N.

    2015-01-01

    OBJECTIVE. The purpose of this study was to evaluate differences in the diagnostic accuracy of absolute and relative territorial myocardial blood flow (MBF) derived from stress dynamic CT myocardial perfusion imaging (MPI) for the detection of significant coronary artery stenosis. MATERIALS AND METH

  6. Non-invasive diagnostic methods in dentistry

    Science.gov (United States)

    Todea, Carmen

    2016-03-01

    The paper, will present the most important non-invasive methods for diagnostic, in different fields of dentistry. Moreover, the laser-based methods will be emphasis. In orthodontics, 3D laser scanners are increasingly being used to establish database for normative population and cross-sectional growth changes but also to asses clinical outcomes in orthognatic surgical and non-surgical treatments. In prevention the main methods for diagnostic of demineralization and caries detection in early stages are represented by laser fluorescence - Quantitative Light Florescence (QLF); DiagnoDent-system-655nm; FOTI-Fiberoptic transillumination; DIFOTI-Digital Imaging Fiberoptic transillumination; and Optical Coherence Tomography (OCT). In odontology, Laser Doppler Flowmetry (LDF) is a noninvasive real time method used for determining the tooth vitality by monitoring the pulp microcirculation in traumatized teeth, fractured teeth, and teeth undergoing different conservative treatments. In periodontology, recently study shows the ability of LDF to evaluate the health of gingival tissue in periodontal tissue diseases but also after different periodontal treatments.

  7. Comprehensive model for simultaneous MRI determination of perfusion and permeability using a blood-pool agent in rats rhabdomyosarcoma

    Energy Technology Data Exchange (ETDEWEB)

    Bazelaire, Cedric de [Saint Louis Hospital, Radiology Department, Paris (France); Siauve, Nathalie; Fournier, Laure; Clement, Olivier; Kerviler, Eric de; Cuenod, Charles Andre [George Pompidou European Hospital, Radiology Department, Paris (France); Frouin, Frederique [INSERM U494, Faculte de Medecine Pitie-Salpetriere, Paris (France); Robert, Philippe [Guerbet Laboratoire Guerbet, Recherche et Developpement, Paris (France)

    2005-12-01

    To present a new compartmental analysis model developed to simultaneously measure tissue perfusion and capillary permeability in a tumor using MRI and a macromolecular contrast medium. Rhadomyosarcomas were implanted subcutaneously in 20 rats and studied by 1.5-T MRI using a fast gradient echo sequence (2D fast SPGR TR/TE/{alpha} 13 ms/1.2 ms/60 ) after injection of a macromolecular contrast medium. The left ventricle and tumor signal intensities were converted into concentrations and modeled using compartmental analysis, yielding tumor perfusion F, distribution volume V{sub distribution}, volume transfer constant K{sup trans}, rate constant of influx k{sub pe}, and initial extraction (fraction) E. Tumor perfusion was F=43{+-}29 ml.min{sup -1}.100 g{sup -1}. The permeability study allowed the measurement of k{sub pe}=0.37{+-}0.12 min{sup -1} and K{sup trans}=0.01{+-}0.0031 min{sup -1}. The blood volume could be assimilated to the distribution volume (V{sub distribution}=2.9{+-}1.01%) since the capillary leakage was small. The simultaneous assessment of perfusion and permeability allowed quantification of the initial extraction (fraction) E=2.34{+-}1.05%. Quantification of both tumor perfusion and capillary leakage is feasible using MRI using a macromolecular blood pool agent. The method should improve tumor characterization. (orig.)

  8. Spatio-temporal cerebral blood flow perfusion patterns in cortical spreading depression

    Science.gov (United States)

    Verisokin, Andrey Yu.; Verveyko, Darya V.; Postnov, Dmitry E.

    2017-04-01

    Cortical spreading depression (CSD) is an example of one of the most common abnormalities in biophysical brain functioning. Despite the fact that there are many mathematical models describing the cortical spreading depression (CSD), most of them do not take into consideration the role of redistribution of cerebral blood flow (CBF), that results in the formation of spatio-temporal patterns. The paper presents a mathematical model, which successfully explains the CBD role in the CSD process. Numerical study of this model has revealed the formation of stationary dissipative structures, visually analogous to Turing structures. However, the mechanism of their formation is not diffusion. We show these structures occur due to another type of spatial coupling, that is related to tissue perfusion rate. The proposed model predicts that at similar state of neurons the distribution of blood flow and oxygenation may by different. Currently, this effect is not taken into account when the Blood oxygen-level dependent (BOLD) contrast imaging used in functional magnetic resonance imaging (fMRI). Thus, the diagnosis on the BOLD signal can be ambiguous. We believe that our results can be used in the future for a more correct interpretation of the data obtained with fMRI, NIRS and other similar methods for research of the brain activity.

  9. Perfusion-weighted imaging and dynamic 4D angiograms for the estimation of collateral blood flow in lacunar infarction.

    Science.gov (United States)

    Förster, Alex; Mürle, Bettina; Böhme, Johannes; Al-Zghloul, Mansour; Kerl, Hans U; Wenz, Holger; Groden, Christoph

    2016-10-01

    Although lacunar infarction accounts for approximately 25% of ischemic strokes, collateral blood flow through anastomoses is not well evaluated in lacunar infarction. In 111 lacunar infarction patients, we analyzed diffusion-weighted images, perfusion-weighted images, and blood flow on dynamic four-dimensional angiograms generated by use of Signal Processing In NMR-Software. Blood flow was classified as absent (type 1), from periphery to center (type 2), from center to periphery (type 3), and combination of type 2 and 3 (type 4). On diffusion-weighted images, lacunar infarction was found in the basal ganglia (11.7%), internal capsule (24.3%), corona radiata (30.6%), thalamus (24.3%), and brainstem (9.0%). In 58 (52.2%) patients, perfusion-weighted image showed a circumscribed hypoperfusion, in one (0.9%) a circumscribed hyperperfusion, whereas the remainder was normal. In 36 (62.1%) patients, a larger perfusion deficit (>7 mm) was observed. In these, blood flow was classified type 1 in four (11.1%), 2 in 17 (47.2%), 3 in 9 (25.0%), and 4 in six (16.7%) patients. Patients with lacunar infarction in the posterior circulation more often demonstrated blood flow type 2 and less often type 3 (p = 0.01). Detailed examination and graduation of blood flow in lacunar infarction by use of dynamic four-dimensional angiograms is feasible and may serve for a better characterization of this stroke subtype.

  10. Assessment of hemodynamics in precancerous lesion of hepatocellular carcinoma: Evaluation with MR perfusion

    Institute of Scientific and Technical Information of China (English)

    Sheng Guan; Wei-Dong Zhao; Kang-Rong Zhou; Wei-Jun Peng; Feng Tang; Jian Mao

    2007-01-01

    AIM: To investigate the hemodynamic changes in a precancerous lesion model of hepatocellular carcinoma (HCC).METHODS: Hemodynamic changes in 18 Wistar rats were studied with non-invasive magnetic resonance (MR)perfusion. The changes induced by diethylnitrosamine (DEN) developed into liver nodular lesions due to hepatic cirrhosis during the progression of carcinogenesis.The MR perfusion data [positive enhancement integral (PEI)] were compared between the nodular lesions corresponding well with MR images and pathology and their surrounding hepatic parenchyma.RESULTS: A total of 46 nodules were located by MR imaging and autopsy, including 22 dysplastic nodules (DN), 9 regenerative nodules (RN), 10 early HCCs and 5 overt HCCs. Among the 22 DNs, 6 were low-grade DN (LGDN) and 16 were high-grade DN (HGDN). The average PEI of RN, DN, early and overt HCC was 205.67± 31.17, 161.94 ± 20.74, 226.09 ± 34.83, 491.86 ±44.61 respectively, and their liver parenchyma nearby was 204.84 ± 70.19. Comparison of the blood perfusion index between each RN and its surrounding hepatic parenchyma showed no statistically significant difference (P = 0.06). There were significant differences in DN (P = 0.02). During the late hepatic arterial phase, the perfusion curve in DN declined. DN had an iso-signal intensity at the early hepatic arterial phase and a low signal intensity at the portal venous phase. Of the 10early HCCs, 4 demonstrated less blood perfusion and 6 displayed minimally increased blood flow compared to the surrounding parenchyma. Five HCCs showed significantly increased blood supply compared to the surrounding parenchyma (P = 0.02).CONCLUSION: Non-invasive MR perfusion can detect changes in blood supply of precancerous lesions.

  11. Perfusion-weighted MR imaging in persistent hemiplegic migraine

    Energy Technology Data Exchange (ETDEWEB)

    Mourand, Isabelle; Menjot de Champfleur, Nicolas; Carra-Dalliere, Clarisse; Le Bars, Emmanuelle; Bonafe, Alain; Thouvenot, Eric [Hopital Gui de Chauliac, Service de Neuroradiologie, Montpellier (France); Roubertie, Agathe [Hopital Gui de Chauliac, Service de Neuropediatrie, Montpellier (France)

    2012-03-15

    Hemiplegic migraine is a rare type of migraine that has an aura characterized by the presence of motor weakness, which may occasionally last up to several days, and then resolve without sequela. Pathogenesis of migraine remains unclear and, recently, perfusion-weighted imaging (PWI) has provided a non-invasive method to study hemodynamic changes during acute attacks. Two female patients were admitted in our hospital suffering from prolonged hemiparesis. In both cases, they underwent MRI examination using a 1.5 T magnet including axial diffusion-weighted and perfusion sequences. From each perfusion MRI acquisition two regions of interest were delineated on each hemisphere and, the index of flow, cerebral blood volume, mean transit time, and time to peak were recorded and asymmetry indices from each perfusion parameter were calculated. Perfusion alterations were detected during the attacks. In one case, we observed, after 3 h of left hemiparesia, hypoperfusion of the right hemisphere. In the other case, who presented a familial hemiplegic migraine attack, on the third day of a persistent aura consisting of right hemiplegia and aphasia, PWI revealed hyperperfusion of the left hemisphere. Asymmetry indices for temporal parameters (mean transit time and time to peak) were the most sensitive. These findings resolved spontaneously after the attacks without any permanent sequel or signs of cerebral ischemia on follow-up MRI. PWI should be indicated for patients with migraine attacks accompanied by auras to assess the sequential changes in cerebral perfusion and to better understand its pathogenesis. (orig.)

  12. Correction of disorders in tissue perfusion, blood coagulation and fibrinolysis with Orbita apparatus on terahertz waves of cell metabolites

    Directory of Open Access Journals (Sweden)

    Vyacheslav F. Kirichuk

    2013-02-01

    Full Text Available This article contains information on principle of operation, technical parameters and possible application of Orbita {transliteration from Russian} apparatus for hemodynamic, fibrinolytic and peripheral perfusion disorders treatment. A single exposure to terahertz waves emitted by Orbita apparatus, corresponding to frequencies of molecular absorption and emission spectra of atmospheric oxygen (129.0 GHz, completely cures coagulant and fibrinolytic disorders of animals with acute immobilization stress. A course of treatment with electromagnetic waves corresponding to frequencies of molecular absorption and emission spectra of nitrogen oxide (150.176 – 150.664 leads to normalization of disrupted peripheral tissue perfusion parameters of animal undergoing treatment and stimulates basal and induced output of nitrogen oxide. This leads to decrease in peripheral vascular resistance to microcirculation and increase in blood flow to microvasculature. Experimental data provided in this article serves as a proof of viability of Orbita apparatus for treatment of coagulant, fibrinolytic and tissue perfusion disorders.

  13. Albumin modulates S1P delivery from red blood cells in perfused microvessels: mechanism of the protein effect.

    Science.gov (United States)

    Adamson, R H; Clark, J F; Radeva, M; Kheirolomoom, A; Ferrara, K W; Curry, F E

    2014-04-01

    Removal of plasma proteins from perfusates increases vascular permeability. The common interpretation of the action of albumin is that it forms part of the permeability barrier by electrostatic binding to the endothelial glycocalyx. We tested the alternate hypothesis that removal of perfusate albumin in rat venular microvessels decreased the availability of sphingosine-1-phosphate (S1P), which is normally carried in plasma bound to albumin and lipoproteins and is required to maintain stable baseline endothelial barriers (Am J Physiol Heart Circ Physiol 303: H825-H834, 2012). Red blood cells (RBCs) are a primary source of S1P in the normal circulation. We compared apparent albumin permeability coefficients [solute permeability (Ps)] measured using perfusates containing albumin (10 mg/ml, control) and conditioned by 20-min exposure to rat RBCs with Ps when test perfusates were in RBC-conditioned protein-free Ringer solution. The control perfusate S1P concentration (439 ± 46 nM) was near the normal plasma value at 37 °C and established a stable baseline Ps (0.9 ± 0.4 × 10(-6) cm/s). Ringer solution perfusate contained 52 ± 8 nM S1P and increased Ps more than 10-fold (16.1 ± 3.9 × 10(-6) cm/s). Consistent with albumin-dependent transport of S1P from RBCs, S1P concentrations in RBC-conditioned solutions decreased as albumin concentration, hematocrit, and temperature decreased. Protein-free Ringer solution perfusates that used liposomes instead of RBCs as flow markers failed to maintain normal permeability, reproducing the "albumin effect" in these mammalian microvessels. We conclude that the albumin effect depends on the action of albumin to facilitate the release and transport of S1P from RBCs that normally provide a significant amount of S1P to the endothelium.

  14. Estimation of rat muscle blood flow by microdialysis probes perfused with ethanol, [14C]ethanol, and 3H2O

    DEFF Research Database (Denmark)

    Stallknecht, B; Donsmark, M; Enevoldsen, L H;

    1999-01-01

    We used the perfused rat hindquarter to evaluate whether the microdialysis ethanol technique can be used to qualitatively estimate nutritive skeletal muscle blood flow. Four microdialysis probes were inserted in different hindlimb muscles in each of 16 rats. Hindquarters were perfused at blood flow...... rates ranging from 0 to 21 ml. 100 g-1. min-1. The microdialysis probes were perfused at 2 microliter/min with perfusate containing ethanol, [14C]ethanol, and 3H2O. Within and between experiments outflow-to-inflow ratios (o/i) generally varied inversely with blood flow. When a low flow or no flow...... was maintained in hindquarters, o/i ratios first increased with time (for at least 60 min) and then leveled off. The long time constant impaired detection of rapid oscillations in blood flow, especially at low blood flow rates. Contractions per se apparently decreased o/i ratios independent of blood flow...

  15. Cerebral misery perfusion diagnosed using hypercapnic blood-oxygenation-level-dependent contrast functional magnetic resonance imaging: a case report

    Directory of Open Access Journals (Sweden)

    D'Souza Olympio

    2010-02-01

    Full Text Available Abstract Introduction Cerebral misery perfusion represents a failure of cerebral autoregulation. It is an important differential diagnosis in post-stroke patients presenting with collapses in the presence of haemodynamically significant cerebrovascular stenosis. This is particularly the case when cortical or internal watershed infarcts are present. When this condition occurs, further investigation should be done immediately. Case presentation A 50-year-old Caucasian man presented with a stroke secondary to complete occlusion of his left internal carotid artery. He went on to suffer recurrent seizures. Neuroimaging demonstrated numerous new watershed-territory cerebral infarcts. No source of arterial thromboembolism was demonstrable. Hypercapnic blood-oxygenation-level-dependent-contrast functional magnetic resonance imaging was used to measure his cerebrovascular reserve capacity. The findings were suggestive of cerebral misery perfusion. Conclusions Blood-oxygenation-level-dependent-contrast functional magnetic resonance imaging allows the inference of cerebral misery perfusion. This procedure is cheaper and more readily available than positron emission tomography imaging, which is the current gold standard diagnostic test. The most evaluated treatment for cerebral misery perfusion is extracranial-intracranial bypass. Although previous trials of this have been unfavourable, the results of new studies involving extracranial-intracranial bypass in high-risk patients identified during cerebral perfusion imaging are awaited. Cerebral misery perfusion is an important and under-recognized condition in which emerging imaging and treatment modalities present the possibility of practical and evidence-based management in the near future. Physicians should thus be aware of this disorder and of recent developments in diagnostic tests that allow its detection.

  16. Optimizing non-invasive radiofrequency hyperthermia treatment for improving drug delivery in 4T1 mouse breast cancer model

    Science.gov (United States)

    Ware, Matthew J.; Krzykawska-Serda, Martyna; Chak-Shing Ho, Jason; Newton, Jared; Suki, Sarah; Law, Justin; Nguyen, Lam; Keshishian, Vazrik; Serda, Maciej; Taylor, Kimberly; Curley, Steven A.; Corr, Stuart J.

    2017-03-01

    Interactions of high-frequency radio waves (RF) with biological tissues are currently being investigated as a therapeutic platform for non-invasive cancer hyperthermia therapy. RF delivers thermal energy into tissues, which increases intra-tumoral drug perfusion and blood-flow. Herein, we describe an optical-based method to optimize the short-term treatment schedules of drug and hyperthermia administration in a 4T1 breast cancer model via RF, with the aim of maximizing drug localization and homogenous distribution within the tumor microenvironment. This method, based on the analysis of fluorescent dyes localized into the tumor, is more time, cost and resource efficient, when compared to current analytical methods for tumor-targeting drug analysis such as HPLC and LC-MS. Alexa-Albumin 647 nm fluorphore was chosen as a surrogate for nab-paclitaxel based on its similar molecular weight and albumin driven pharmacokinetics. We found that RF hyperthermia induced a 30–40% increase in Alexa-Albumin into the tumor micro-environment 24 h after treatment when compared to non-heat treated mice. Additionally, we showed that the RF method of delivering hyperthermia to tumors was more localized and uniform across the tumor mass when compared to other methods of heating. Lastly, we provided insight into some of the factors that influence the delivery of RF hyperthermia to tumors.

  17. Reducing body fat with altitude hypoxia training in swimmers: role of blood perfusion to skeletal muscles.

    Science.gov (United States)

    Chia, Michael; Liao, Chin-An; Huang, Chih-Yang; Lee, Wen-Chih; Hou, Chien-Wen; Yu, Szu-Hsien; Harris, M Brennan; Hsu, Tung-Shiung; Lee, Shin-Da; Kuo, Chia-Hua

    2013-02-28

    Swimmers tend to have greater body fat than athletes from other sports. The purpose of the study was to examine changes in body composition after altitude hypoxia exposure and the role of blood distribution to the skeletal muscle in swimmers. With a constant training volume of 12.3 km/day, young male swimmers (N = 10, 14.8 ± 0.5 years) moved from sea-level to a higher altitude of 2,300 meters. Body composition was measured before and after translocation to altitude using dual-energy X-ray absorptiometry (DXA) along with 8 control male subjects who resided at sea level for the same period of time. To determine the effects of hypoxia on muscle blood perfusion, total hemoglobin concentration (THC) was traced by near-infrared spectroscopy (NIRS) in the triceps and quadriceps muscles under glucose-ingested and insulin-secreted conditions during hypoxia exposure (16% O2) after training. While no change in body composition was found in the control group, subjects who trained at altitude had unequivocally decreased fat mass (-1.7 ± 0.3 kg, -11.4%) with increased lean mass (+0.8 ± 0.2 kg, +1.5%). Arterial oxygen saturation significantly decreased with increased plasma lactate during hypoxia recovery mimicking 2,300 meters at altitude (~93% versus ~97%). Intriguingly, hypoxia resulted in elevated muscle THC, and sympathetic nervous activities occurred in parallel with greater-percent oxygen saturation in both muscle groups. In conclusion, the present study provides evidence that increased blood distribution to the skeletal muscle under postprandial condition may contribute to the reciprocally increased muscle mass and decreased body mass after a 3-week altitude exposure in swimmers.

  18. Non-invasive monitoring of endocrine status in laboratory primates: methods, guidelines and applications

    Science.gov (United States)

    Heistermann, M.

    2010-11-01

    During the past three decades, non-invasive methods for assessing physiological, in particular endocrine, status have revolutionized almost all areas of primatology, including behavioural ecology, reproductive biology, stress research, conservation and last but not least management of primates in captivity where the technology plays an integral role in assisting the husbandry, breeding and welfare of many species. Non-invasive endocrine methods make use of the fact that hormones circulating in blood are secreted into saliva or deposited in hair and are eliminated from the body via urinary and faecal excretion. The choice of which matrix to use for hormonal assessment depends on a range of factors, including the type of information required, the measurement techniques involved, species differences in hormone metabolism and route of excretion and the practicality of sample collection. However, although sample collection is usually relatively easy, analysing hormones from these non-invasively collected samples is not as easy as many people think, particularly not when dealing with a new species. In this respect, the importance of a careful validation of each technique is essential in order to generate meaningful and accurate results. This paper aims to provide an overview of the available non-invasive endocrine-based methodologies, their relative merits and their potential areas of application for assessing endocrine status in primates, with special reference to captive environments. In addition, general information is given about the most important aspects and caveats researchers have to be aware of when using these methodologies.

  19. Non-invasive Technology for Arterial Blood Pressure Signal Based on Photo-diode%基于光电二极管的动脉血压信号无损监测技术

    Institute of Scientific and Technical Information of China (English)

    熊元姣

    2015-01-01

    用红外发光二极管和光电二极管组成的光耦合指套,放置在人身体的指尖部位,通过检测人体末梢组织在动脉舒张和收缩时对红外光的吸收度变化率,来检测人体动脉血压信号的异常。红外发射二极管的驱动采用PWM信号调制的恒流驱动,光电二极管接收穿透人体后的红外光并转换成微弱的电信号,再经过前置放大、倒相、压控二阶低通滤波、陷波电路、A/D 转换等处理后,MCU 从采集的数据中提取有关动脉血压信号的特征值,实现血压信号异常的无损连续监测。%An optical coupling finger stall, composed of IR LED and photo-diode, is placed at fingertip, when the IR transmission light intensity across a finger changes with the diastole and systole of arterial blood pressure, the inverter current of photo-diode varies. Therefore, the arterial blood pressure anomalies can be detected according to the changes. The drive current of IR LED, controlled by PWM is constant in the process of detection. The voltage signal converted by photo-diode is very week, so that it can easily be disturbed. The signal must be processed by the pre-amplification circuit, second order filter circuit, and wave trap. Finally, the data from A/D converter is collected and processed by MCU.

  20. Compact Laser Doppler Flowmeter (LDF Fundus Camera for the Assessment of Retinal Blood Perfusion in Small Animals.

    Directory of Open Access Journals (Sweden)

    Marielle Mentek

    Full Text Available Noninvasive techniques for ocular blood perfusion assessment are of crucial importance for exploring microvascular alterations related to systemic and ocular diseases. However, few techniques adapted to rodents are available and most are invasive or not specifically focused on the optic nerve head (ONH, choroid or retinal circulation. Here we present the results obtained with a new rodent-adapted compact fundus camera based on laser Doppler flowmetry (LDF.A confocal miniature flowmeter was fixed to a specially designed 3D rotating mechanical arm and adjusted on a rodent stereotaxic table in order to accurately point the laser beam at the retinal region of interest. The linearity of the LDF measurements was assessed using a rotating Teflon wheel and a flow of microspheres in a glass capillary. In vivo reproducibility was assessed in Wistar rats with repeated measurements (inter-session and inter-day of retinal arteries and ONH blood velocity in six and ten rats, respectively. These parameters were also recorded during an acute intraocular pressure increase to 150 mmHg and after heart arrest (n = 5 rats.The perfusion measurements showed perfect linearity between LDF velocity and Teflon wheel or microsphere speed. Intraclass correlation coefficients for retinal arteries and ONH velocity (0.82 and 0.86, respectively indicated strong inter-session repeatability and stability. Inter-day reproducibility was good (0.79 and 0.7, respectively. Upon ocular blood flow cessation, the retinal artery velocity signal substantially decreased, whereas the ONH signal did not significantly vary, suggesting that it could mostly be attributed to tissue light scattering.We have demonstrated that, while not adapted for ONH blood perfusion assessment, this device allows pertinent, stable and repeatable measurements of retinal blood perfusion in rats.

  1. Dynamic subcortical blood flow during male sexual activity with ecological validity : A perfusion NRI study

    NARCIS (Netherlands)

    Georgiadis, Janniko R.; Farrell, Michael J.; Boessen, Ruud; Denton, Derek A.; Gavrilescu, Maria; Kortekaas, Rudie; Renken, Remco J.; Hoogduin, Johannes M.; Egan, Gary F.

    This study used arterial spin labeling (ASL) fMRI to measure brain perfusion in a group of healthy men under conditions that closely resembled customary sexual behavior. Serial perfusion measures for 30 min during two self-limited periods of partnered penis stimulation, and during post-stimulatory

  2. Three distinct phases of VF during global ischemia in the isolated blood-perfused pig heart.

    Science.gov (United States)

    Huizar, Jose F; Warren, Mark D; Shvedko, Alexander G; Kalifa, Jérôme; Moreno, Javier; Mironov, Sergey; Jalife, José; Zaitsev, Alexey V

    2007-09-01

    Changes in ventricular fibrillation (VF) organization occurring after the onset of global ischemia are relevant to defibrillation and survival but remain poorly understood. We hypothesized that ischemia-specific dynamic instability of the action potential (AP) causes a loss of spatiotemporal periodicity of propagation and broadening of the electrocardiogram (ECG) frequency spectrum during VF in the ischemic myocardium. We recorded voltage-sensitive fluorescence of di-4-ANEPPS (anterior left ventricle, 35 x 35 mm, 64 x 64 pixels) and the volume-conducted ECG in six blood-perfused hearts during 10 min of VF and global ischemia. We used coefficient of variation (CV) to estimate variability of AP amplitude, AP duration, and diastolic interval (CV-APA, CV-APD, and CV-DI, respectively). We computed excitation median frequency (Median_F), spectral width of the AP and ECG (SpW-AP and SpW-ECG, respectively), wavebreak incidence (WBI), and recurrence of propagation direction (RPD). We found three distinct phases of local VF dynamics: "relatively periodic" (broadening of the ECG spectrum during VF evolution.

  3. Fade of the responses of the isolated, blood-perfused dog atrium to cholinergic interventions.

    Science.gov (United States)

    Furukawa, Y; Martin, P; Levy, M N

    1984-05-01

    In the isolated, blood-perfused, canine right atrium, intramural parasympathetic nerve stimulation and intra-arterial infusions of acetylcholine induced substantial negative chronotropic and inotropic responses. The responses to parasympathetic stimulation reached their maximum values quickly, and then usually faded back toward control levels over the next 1 or 2 min of stimulation. The fade of the responses at high stimulation frequencies (greater than or equal to 30 Hz) was significantly greater than that at lower frequencies. The inotropic responses to acetylcholine infusion (1 microgram/min) faded slightly but significantly, whereas the chronotropic responses did not fade at all. These results suggest that the fade of the cardiac responses to parasympathetic stimulation is mainly ascribable to a progressive reduction in the rate of acetylcholine release from the nerve endings, especially at higher stimulation frequencies. The fade of the inotropic responses was more pronounced and had a longer time course than that of the chronotropic responses. Furthermore, the fade of the inotropic responses diminished significantly as the response magnitude was augmented by an increase in stimulation voltage. Conversely, the fade of chronotropic responses was not significantly affected by this intervention. These differences in the inotropic and chronotropic responses to neural stimulation, and the occurrence of a slight fade of the inotropic response to acetylcholine infusion, suggest that in addition to the predominant prejunctional mechanism, a postjunctional phenomenon may also be partly responsible for the fade of the inotropic response to cholinergic interventions.

  4. The effect of home oxygen therapy and non-invasive bi-level positive pressure ventilation on blood gas changes and the life quality in patients with overlap syndrome%家庭氧疗及双水平无创通气对重叠综合征患者血气分析结果和生活质量的影响

    Institute of Scientific and Technical Information of China (English)

    姚桂飞; 冯加喜; 龚柳阳

    2012-01-01

    Objective To investigate the effect of home oxygen therapy and non-invasive bi-level positive ventilation ( BiPAP) on blood gas changes and life quality of patients with overlap syndrome. Methods 38 patients with home oxygen therapy treatment and 42 patients with BiPAP treatment were selected, and blood gas analysis ( pH, PaO2 ,and PaCO2 values) and questionnaire of life quality were used to analyze the home oxygen therapy and non-invasive bi-level positive ventilation (BiPAP) on blood gas changes and life quality. Results Blood pH and PaO2 of BiPAP group after treatment were significantly higher than those before treatment (P <0. 05). Blood PaCO2 of BiPAP group after treatment were significantly lower than those before treatment (P <0. 05) . There was no significant differ-ence between blood PH,PO2 and blood PaCO2 of home oxygen therapy group before and after treatment. Blood pH and PaO2 BiPAP group increased with time during the treatment period ( P < 0. 05 ) , and blood PaC02 of BiPAP group decreased gradually the normal level(P <0.05) ,there was no significant difference between blood pH,PaO2 and blood PaC02 of home oxygen therapy group during the treatment period. Life quality of the patients of BiPAP group significantly was improved,but not in the home oxygen therapy group. Conclusion The non-invasive bi-level positive pressure ventilation (BiPAP) can improve effect blood gas changes and life quality of patients with overlap syndrome more significant than the home oxygen therapy.%目的 探讨家庭氧疗及双水平无创通气对重叠综合征患者血气分析结果和生活质量的影响.方法 38例经家庭氧疗和42例经双水平无创通气治疗的重叠综合征患者,分析治疗前后患者血液中pH、PaO2,PaCO2值变化情况,并通过调查问卷方式分析治疗前后生活质量.结果 双水平无创通气组治疗后血pH和血PaO2均显著高于治疗前(均P<0.05),血PaCO2显著低于治疗前(P<0.05);家庭氧疗

  5. Thermal behavior of human eye in relation with change in blood perfusion, porosity, evaporation and ambient temperature.

    Science.gov (United States)

    Rafiq, Aasma; Khanday, M A

    2016-12-01

    Extreme environmental and physiological conditions present challenges for thermal processes in body tissues including multi-layered human eye. A mathematical model has been formulated in this direction to study the thermal behavior of the human eye in relation with the change in blood perfusion, porosity, evaporation and environmental temperatures. In this study, a comprehensive thermal analysis has been performed on the multi-layered eye using Pennes' bio-heat equation with appropriate boundary and interface conditions. The variational finite element method and MATLAB software were used for the solution purpose and simulation of the results. The thermoregulatory effect due to blood perfusion rate, porosity, ambient temperature and evaporation at various regions of human eye was illustrated mathematically and graphically. The main applications of this model are associated with the medical sciences while performing laser therapy and other thermoregulatory investigation on human eye.

  6. Early CT perfusion changes and blood-brain barrier permeability after aneurysmal subarachnoid hemorrhage

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, Amanda; Bharatha, Aditya [University of Toronto, Department of Medical Imaging, Toronto, ON (Canada); De Oliveira Manoel, Airton Leonardo; Kouzmina, Ekaterina [St. Michael' s Hospital, Toronto (Canada); Burgers, Kyle; Lee, Ting [Robarts Research Institute, London (Canada); Macdonald, R.L. [St. Michael' s Hospital, Department of Neurosurgery, Toronto (Canada)

    2015-08-15

    Early brain injury (EBI) can occur within 72 h of aneurysmal subarachnoid hemorrhage (aSAH). The objective of this study was to determine if there are differences in early CTP parameters (<72 h) with respect to delayed cerebral ischemia (DCI), cerebral infarction, and functional outcome. We performed a prospective cohort study of aSAH patients admitted to a single tertiary care center. MTT, CBF and blood-brain barrier permeability (PS) were quantified with CTP within 72 h of aneurysm rupture. Primary outcomes were functional outcome by the Modified Rankin Scale (mRS) at 3 months and cerebral infarction. Secondary outcome was the development of DCI. Differences between early CTP parameters were determined with respect to primary and secondary outcomes. Fifty aSAH patients were included in the final analysis. MTT was significantly higher in patients who developed DCI (6.7 ± 1.2 vs 5.9 ± 1.0; p = 0.03) and cerebral infarction (7.0 ± 1.2 vs 5.9 ± 0.9; p = 0.007); however, no difference in MTT was found between patients with and without a poor outcome (mRS > 2). Early CBF and PS did not differ with respect to functional outcome, DCI, and cerebral infarction. Elevated MTT within 72 h of aneurysm rupture is associated with DCI and cerebral infarction but not with long-term functional outcome. Blood-brain barrier permeability, as assessed by CT perfusion, was not associated with DCI or worse outcome in this cohort. (orig.)

  7. Non-invasive photo acoustic approach for human bone diagnosis.

    Science.gov (United States)

    Thella, Ashok Kumar; Rizkalla, James; Helmy, Ahdy; Suryadevara, Vinay Kumar; Salama, Paul; Rizkalla, Maher

    2016-12-01

    The existing modalities of bone diagnosis including X-ray and ultrasound may cite drawback in some cases related to health issues and penetration depth, while the ultrasound modality may lack image quality. Photo acoustic approach however, provides light energy to the acoustic wave, enabling it to activate and respond according to the propagating media (which is type of bones in this case). At the same time, a differential temperature change may result in the bio heat response, resulting from the heat absorbed across the multiple materials under study. In this work, we have demonstrated the features of using photo acoustic modality in order to non-invasively diagnose the type of human bones based on their electrical, thermal, and acoustic properties that differentiate the output response of each type. COMSOL software was utilized to combine both acoustic equations and bio heat equations, in order to study both the thermal and acoustic responses through which the differential diagnosis can be obtained. In this study, we solved both the acoustic equation and bio heat equations for four types of bones, bone (cancellous), bone (cortical), bone marrow (red), and bone marrow (yellow). 1 MHz acoustic source frequency was chosen and 10(5) W/m(2) power source was used in the simulation. The simulation tested the dynamic response of the wave over a distance of 5 cm from each side for the source. Near 2.4 cm was detected from simulation from each side of the source with a temperature change of within 0.5 K for various types of bones, citing a promising technique for a practical model to detect the type of bones via the differential temperature as well as the acoustic was response via the multiple materials associated with the human bones (skin and blood). The simulation results suggest that the PA technique may be applied to non-invasive diagnosis for the different types of bones, including cancerous bones. A practical model for detecting both the temperature change via

  8. Pulmonary perfusion with oxygenated blood or custodiol HTK solution during cardiac surgery for postoperative pulmonary function in COPD patients

    DEFF Research Database (Denmark)

    Buggeskov, Katrine B; Wetterslev, Jørn; Secher, Niels H;

    2013-01-01

    Five to thirty percent of patients undergoing cardiac surgery present with chronic obstructive pulmonary disease (COPD) and have a 2- to 10-fold higher 30-day mortality risk. Cardiopulmonary bypass (CPB) creates a whole body systemic inflammatory response syndrome (SIRS) that could impair pulmona...... function. Impaired pulmonary function can, however, be attenuated by pulmonary perfusion with oxygenated blood or custodiol HTK (histidine-tryptophan-ketoglutarate) solution....

  9. Oxygen saturation, red blood cell tissue fraction and speed resolved perfusion - A new optical method for microcirculatory assessment.

    Science.gov (United States)

    Jonasson, Hanna; Fredriksson, Ingemar; Pettersson, Anders; Larsson, Marcus; Strömberg, Tomas

    2015-11-01

    We have developed a new fiber-optic system that combines diffuse reflectance spectroscopy (DRS) and laser Doppler Flowmetry (LDF) for a multi-modal assessment of the microcirculation. Quantitative data is achieved with an inverse Monte Carlo algorithm based on an individually adaptive skin model. The output parameters are calculated from the model and given in absolute units: hemoglobin oxygen saturation (%), red blood cell (RBC) tissue fraction (%), and the speed resolved RBC perfusion separated into three speed regions; 0-1mm/s, 1-10mm/s and above 10mm/s (% mm/s). The aim was to explore microcirculatory parameters using the new optical method, integrating DRS and LDF in a joint skin model, during local heating of the dorsal foot and venous and arterial occlusion of the forearm in 23 healthy subjects (age 20-28years). There were differences in the three speed regions in regard to blood flow changes due to local heating, where perfusion for high speeds increased the most. There was also a high correlation between changes in oxygenation and changes in perfusion for higher speeds. Oxygen saturation at baseline was 44% on foot, increasing to 83% at plateau after heating. The larger increase in perfusion for higher speeds than for lower speeds together with the oxygenation increase during thermal provocation, shows a local thermoregulatory blood flow in presumably arteriolar dermal vessels. In conclusion, there are improved possibilities to assess microcirculation using integrated DRS and LDF in a joint skin model by enabling both oxygenation and speed resolved blood flow assessment simultaneously and in the same skin site. Output parameters in absolute units may also yield new insights about the microcirculatory system.

  10. Non-invasive Imaging of Human Embryonic Stem Cells

    OpenAIRE

    Hong, Hao; Yang, Yunan; Zhang, Yin; Cai, Weibo

    2010-01-01

    Human embryonic stem cells (hESCs) hold tremendous therapeutic potential in a variety of diseases. Over the last decade, non-invasive imaging techniques have proven to be of great value in tracking transplanted hESCs. This review article will briefly summarize the various techniques used for non-invasive imaging of hESCs, which include magnetic resonance imaging (MRI), bioluminescence imaging (BLI), fluorescence, single-photon emission computed tomography (SPECT), positron emission tomography...

  11. Non-invasive prediction of oesophageal varices in cirrhosis

    Institute of Scientific and Technical Information of China (English)

    Sambit Sen; William JH Griffiths

    2008-01-01

    Non-invasive predictors of varices in cirrhosis would reduce the need for screening endoscopies. Platelet count and spleen size have been shown to be useful parameters, in mixed groups of cirrhotics with different aetiologies. We evaluated this in two homogeneous groups with cirrhosis due to hepatitis C and alcohol.Non-invasive predictors appear promising in the former group, but less so in the latter group.

  12. Non-invasive, Focused Ultrasound-Facilitated Gene Delivery for Optogenetics

    Science.gov (United States)

    Wang, Shutao; Kugelman, Tara; Buch, Amanda; Herman, Mathieu; Han, Yang; Karakatsani, Maria Eleni; Hussaini, S. Abid; Duff, Karen; Konofagou, Elisa E.

    2017-01-01

    Optogenetics, a widely used technique in neuroscience research, is often limited by its invasive nature of application. Here, we present a noninvasive, ultrasound-based technique to introduce optogenetic channels into the brain by temporarily opening the blood-brain barrier (BBB). We demonstrate the efficiency of the method developed and evaluate the bioactivity of the non-invasively introduced channelrhodopsin channels by performing stimulation in freely behaving mice.

  13. Effect of a distal protection device on epicardial blood flow and myocardial perfusion in primary percutaneous coronary intervention

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objective: The beneficial effect of percutaneous coronary intervention (PCI) in patients with acute myocardial infarction (AMI) has been well established, but there is the problem of no-reflow phenomenon which is an adverse prognostic factor in primary PCI. In the present study the effect of a distal protection device (PercuSurge GuardWire; GW) on epicardial blood flow and myocardial perfusion was evaluated. Methods and Results: Patients with AMI were randomly divided into 2 groups, the GW and the control groups. The GW group included 52 patients with AMI who underwent primary PCI with GW protection and the control group included 60 patients who underwent primary PCI without GW protection. Epicardial blood flow in the infarct-related artery (IRA) and myocardial perfusion were evaluated according to the thrombolysis in myocardial infarction (TIMI) flow grade and the myocardial blush grade (MBG). We found TIMI score of 3 was obtained significantly more frequently in the GW group (96%) than in the control group (80%). The MBG score of 3 was obtained also significantly greater in the GW group (65%) than in the control group (33%). Conclusion: Primary PCI with GW protection can significantly improve epicardial blood flow and myocardial perfusion.

  14. Flow measurements in a blood-perfused collagen vessel using x-ray micro-particle image velocimetry.

    Science.gov (United States)

    Antoine, Elizabeth; Buchanan, Cara; Fezzaa, Kamel; Lee, Wah-Keat; Rylander, M Nichole; Vlachos, Pavlos

    2013-01-01

    Blood-perfused tissue models are joining the emerging field of tumor engineering because they provide new avenues for modulation of the tumor microenvironment and preclinical evaluation of the therapeutic potential of new treatments. The characterization of fluid flow parameters in such in-vitro perfused tissue models is a critical step towards better understanding and manipulating the tumor microenvironment. However, traditional optical flow measurement methods are inapplicable because of the opacity of blood and the thickness of the tissue sample. In order to overcome the limitations of optical method we demonstrate the feasibility of using phase-contrast x-ray imaging to perform microscale particle image velocimetry (PIV) measurements of flow in blood perfused hydrated tissue-representative microvessels. However, phase contrast x-ray images significantly depart from the traditional PIV image paradigm, as they have high intensity background, very low signal-to-noise ratio, and volume integration effects. Hence, in order to achieve accurate measurements special attention must be paid to the image processing and PIV cross-correlation methodologies. Therefore we develop and demonstrate a methodology that incorporates image preprocessing as well as advanced PIV cross-correlation methods to result in measured velocities within experimental uncertainty.

  15. Flow measurements in a blood-perfused collagen vessel using x-ray micro-particle image velocimetry.

    Directory of Open Access Journals (Sweden)

    Elizabeth Antoine

    Full Text Available Blood-perfused tissue models are joining the emerging field of tumor engineering because they provide new avenues for modulation of the tumor microenvironment and preclinical evaluation of the therapeutic potential of new treatments. The characterization of fluid flow parameters in such in-vitro perfused tissue models is a critical step towards better understanding and manipulating the tumor microenvironment. However, traditional optical flow measurement methods are inapplicable because of the opacity of blood and the thickness of the tissue sample. In order to overcome the limitations of optical method we demonstrate the feasibility of using phase-contrast x-ray imaging to perform microscale particle image velocimetry (PIV measurements of flow in blood perfused hydrated tissue-representative microvessels. However, phase contrast x-ray images significantly depart from the traditional PIV image paradigm, as they have high intensity background, very low signal-to-noise ratio, and volume integration effects. Hence, in order to achieve accurate measurements special attention must be paid to the image processing and PIV cross-correlation methodologies. Therefore we develop and demonstrate a methodology that incorporates image preprocessing as well as advanced PIV cross-correlation methods to result in measured velocities within experimental uncertainty.

  16. Factors affecting the lung perfused blood volume in patients with intrapulmonary clots after anti-coagulation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Okada, Munemasa, E-mail: radokada@yamaguchi-u.ac.jp [Department of Radiology, Yamaguchi University Graduate School of Medicine 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan); Masuda, Yu [4th Grade of 6-year Medicine Doctor Program, Department of Medicine, Yamaguchi University Faculty of Medicine and Health Sciences 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan); Nakashima, Yoshiteru [Department of Radiology, Yamaguchi Grand Medical Center, Oosaki 77, Hofu, Yamaguchi 747-8511 (Japan); Nomura, Takafumi; Nakao, Sei [Department of Radiology, Yamaguchi University Graduate School of Medicine 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan); Suga, Kazuyoshi [Department of Radiology, St Hills Hospital, Imamurakita 3-7-18, Ube, Yamaguchi 755-0155 (Japan); Kido, Shoji [Computer-aided Diagnosis and Biomedical Imaging Research Biomedical Engineering, Applied Medical Engineering Science Graduate School of Medicine, Yamaguchi University, Tokiwadai 2-16-1, Ube, Yamaguchi 755-8611 (Japan); Matsunaga, Naofumi [Department of Radiology, Yamaguchi University Graduate School of Medicine 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan)

    2015-08-15

    Highlights: • Dual-energy CT can provide morphological and functional lung images in the same examination. • The subsequent dual-energy CT demonstrates the increased whole lung perfused blood volume (V{sub 120}) despite the residual intrapulmonary clots after treatment in one examination. • The increased whole lung perfusion (V{sub 120}) and a decreased low perfusion volume (V{sub 5}) result in the improvement in the low perfusion rate (%V{sub 5}) in the patients with acute pulmonary embolism after treatment. - Abstract: Objectives: Factors affecting the improvement in the lung perfused blood volume (LPBV) were evaluated based on the presence of intrapulmonary clots (IPCs) after anti-coagulation therapy using 64-slice dual-energy CT. Materials and methods: 96 patients exhibiting venous thromboembolism underwent initial and repeated LPBV examinations between December 2008 and July 2014. Fifteen patients were excluded due to pulmonary comorbidities, and a total of 81 patients were included in this study. Acute pulmonary embolism (PE) was diagnosed in 46 of the patients (56.7%). LPBV images were three-dimensionally reconstructed with two threshold ranges: 1–120 HU (V{sub 120}) and 1–5 HU (V{sub 5}), and the relative value of V{sub 5} per V{sub 120} expressed as %V{sub 5}. These values were subsequently compared with indicators of the severity of PE, such as the D-dimer level, heart rate and CT measurements. This study was approved by the local ethics committee. Results: In patients with IPCs, the D-dimer, V{sub 5} and %V{sub 5}values were significantly larger (p ≤ 0.01) in the initial LPBV, although these differences disappeared in subsequent LPBV after treatment. The right ventricular (RV) diameter, RV/left ventricular (RV/LV) diameter ratio and %V{sub 5} values were also significantly reduced, whereas the V{sub 5} value did not significantly decrease (p = 0.07), but V{sub 120} value significantly increased (p < 0.001) after treatment. However, in

  17. Comparison of cerebral blood volume and permeability in preoperative grading of intracranial glioma using CT perfusion imaging

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Bei; Ling, Hua Wei; Chen, Ke Min [Shanghai Jiaotong University, Department of Radiology, Ruijin Hospital, School of Medicine, Shanghai (China); Jiang, Hong [Shanghai Jiaotong University, Department of Pathology, Ruijin Hospital, School of Medicine, Shanghai (China); Zhu, Yan Bo [Shanghai Jiaotong University, Department of Neurosurgery, Ruijin Hospital, School of Medicine, Shanghai (China)

    2006-10-15

    Regional cerebral blood volume (rCBV) and permeability surfaces (rPS) permit in vivo assessment of glioma microvasculature, which provides quite important pathophysiological information in grading gliomas. The aim of our study was to simultaneously examine rCBV and rPS in glioma patients to determine their correlation with histological grade using CT perfusion imaging. A total of 22 patients with gliomas underwent multislice CT perfusion imaging preoperatively. Low-grade and high-grade groups were categorized corresponding to WHO grade II gliomas and WHO grade III or IV gliomas, respectively, as determined by histopathological examination. rCBVs and rPSs were obtained from regions of maximal abnormality in tumor parenchyma on CBV and PS color perfusion maps. Perfusion parameters were compared using the Kruskal-Wallis test in order to evaluate the differences in relation to tumor grade. The Pearson coefficients of rCBV and rPS for each tumor grade were assessed using SPSS 13.0 software. (orig.)

  18. Double-echo perfusion-weighted MR imaging: basic concepts and application in brain tumors for the assessment of tumor blood volume and vascular permeability

    OpenAIRE

    Uematsu, Hidemasa; Maeda, Masayuki

    2006-01-01

    Perfusion-weighted magnetic resonance (MR) imaging using contrast agents plays a key role in characterizing tumors of the brain. We have shown that double-echo perfusion-weighted MR imaging (DEPWI) is potentially useful in assessing brain tumors. Quantitative indices, such as tumor blood volume, are obtained using DEPWI, which allows correction of underestimation of tumor blood volume due to leakage of contrast agents from tumor vessels, in addition to simultaneous acquisition of tumor vessel...

  19. Non-invasive optical mapping of the piglet brain in real time

    Science.gov (United States)

    Fantini, Sergio; Franceschini, Maria Angela; Gratton, Enrico; Hueber, Dennis; Rosenfeld, Warren; Maulik, Dev; Stubblefield, Phillip; Stankovic, Mikjan

    1999-04-01

    We have performed non-invasive, real-time optical mapping of the piglet brain during a subcortical injection of autologous blood. The time resolution of the optical maps is 192 ms, thus allowing us to generate a real-time video of the growing subcortical hematoma. The increased absorption at the site of blood injection is accompanied by a decreased absorption at the contralateral brain side. This contralateral decrease in the optical absorption and the corresponding time traces of the cerebral hemoglobin parameters are consistent with a reduced cerebral blood flow caused by the increased intracranial pressure.

  20. Three-dimensional whole-brain perfused blood volume imaging with multimodal CT for evaluation of acute ischaemic stroke

    Energy Technology Data Exchange (ETDEWEB)

    Lu, J.; Zhang, M.; Cao, Y. [Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing (China); Ma, Q. [Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing (China); Chen, J. [Healthcare, Siemens Ltd. China, Beijing (China); Ji, X. [Department of Neurosurgery Xuanwu Hospital, Capital Medical University, Beijing (China); Li, K., E-mail: imaging@yeah.ne [Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing (China)

    2011-06-15

    Aim: To determine the diagnostic value of integrating three-dimensional perfused blood volume (3D PBV) with multimodal computed tomography (CT) [non-enhanced CT (NECT), CT perfusion (CTP), and CT angiography (CTA)] in acute ischaemic stroke. Materials and methods: NECT, CTP, and CTA were performed in 25 acute ischaemic stroke patients. The ischaemia detection rate of 3D PBV was compared with the results of baseline NECT and CTP. The correlation of ischaemic lesion volume between 3D PBV, CTP images, and follow-up NECT were analysed. Results: NECT demonstrated ischaemic signs in 12 of 25 patients with proven infarction. CTP maps of cerebral blood flow (CBF), cerebral blood volume (CBV), and time to peak (TTP) all demonstrated perfusion deficits in 21 of 25 patients. However, 3D PBV demonstrated perfusion deficits in all of the 25 patients. Among the 25 patients, a strong correlation was found between PBV and the follow-up NECT infarct (r = 0.858). The correlation between CTP and the follow-up NECT infarct as following: CBF (r = 0.718), CBV (r = 0.785), and TTP (r = 0.569). In 14 thrombolytic patients, strong correlation was found between the ischaemic volume on 3D PBV and follow-up NECT (r = 0.798). Conclusion: In acute stroke patients, the combination of 3D PBV and multimodal CT (NECT, CTP, and CTA) can improve the detection rate of ischaemia and enable assessment of the full extent of ischaemia, which correlates well with follow-up NECT.

  1. Myocardial perfusion quantification using the T1 -based FAIR-ASL method: the influence of heart anatomy, cardiopulmonary blood flow and look-locker readout.

    Science.gov (United States)

    Kampf, Thomas; Helluy, Xavier; Gutjahr, Fabian T; Winter, Patrick; Meyer, Cord B; Jakob, Peter M; Bauer, Wolfgang R; Ziener, Christian H

    2014-05-01

    The quantification of myocardial perfusion using a Look-Locker flow-sensitive alternating inversion recovery- arterial spin labeling experiment is considered. Due to the anatomy of the heart, a substantial but unintended partial inversion of the inflowing blood occurs during the slice-selective inversion. Both, the partial inversion as well as the Look-Locker pulse train, influence the myocardial perfusion quantification and are addressed in this work. The mean relaxation time approximation is used to calculate the monoexponential relaxation time of the signal in perfused tissue under Look-Locker readout. The left ventricular blood serves as an approximation of the inflowing blood in the description of FAIR-ASL measurements with global and slice-selective inversion to correctly quantify the myocardial perfusion. The analysis shows that the myocardial perfusion can be overestimated if the T1 -based quantification method is not adapted respecting the Look-Locker pulse train explicitly. Additionally, it turns out that without correction for the partial inversion of the blood pool during the slice-selective inversion the myocardial perfusion is underestimated. It is shown that the Look-Locker readout as well as the nonideal slice-selective inversion experiment have a considerable influence and have to be included properly to correctly quantify myocardial perfusion. Copyright © 2013 Wiley Periodicals, Inc.

  2. Non-invasive investigation in patients with inflammatory joint disease

    Institute of Scientific and Technical Information of China (English)

    Elisabetta Dal Pont; Renata DТncá; Antonino Caruso; Giacomo Carlo Sturniolo

    2009-01-01

    Gut inflammation can occur in 30%-60% of patients with spondyloarthropathies. However, the presence of such gut inflammation is underestimated, only 27% of patients with histological evidence of gut inflammation have intestinal symptoms, but subclinical gut inflammation is documented in two-thirds of patients with inflammatory joint disease. There are common genetic and immunological mechanisms behind concomitant inflammation in the joints and intestinal tract. A number of blood tests, e.g. erythrocyte sedimentation rate, orosomucoid, C-reactive protein, and white cell and platelet counts, are probably the most commonly used laboratory markers of inflammatory disease, however, these tests are difficult to interpret in arthropathies associated with gut inflammation, since any increases in their blood levels might be attributable to either the joint disease or to gut inflammation. Consequently, it would be useful to have a marker capable of separately identifying gut inflammation. Fecal proteins, which are indirect markers of neutrophil migration in the gut wall, and intestinal permeability, seem to be ideal for monitoring intestinal inflammation:they are easy to measure non-invasively and are specific for intestinal disease in the absence of gastrointestinal infections.Alongside the traditional markers for characterizing intestinal inflammation, there are also antibodies, in all probability generated by the immune response to microbial antigens and auto-antigens, which have proved useful in establishing the diagnosis and assessing the severity of the condition, as well as the prognosis and the risk of complications. In short, noninvasive investigations on the gut in patients with rheumatic disease may be useful in clinical practice for a preliminary assessment of patients with suspected intestinal disease.

  3. Prediction of residual lung function after lung surgery, and examination of blood perfusion in the pre- and postoperative lung using three-dimensional SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Shimatani, Shinji [Toho Univ., Tokyo (Japan). School of Medicine

    2001-01-01

    In order to predict postoperative pulmonary function after lung surgery, preoperative {sup 99m}Tc-macroaggregated albumin (MAA) lung perfusion scans with single-photon emission computed tomography (SPECT) were performed. Spirometry was also performed before and 4-6 months after surgery in 40 patients. In addition, changes in blood perfusion in the pre- and postoperative lung were examined by postoperative lung perfusion scans in 18 of the 40 patients. We measured the three-dimensional (3-D) imaging volume of the operative and contralateral lungs using the volumes rendering method at blood perfusion thresholds of 20, 50 and 75%, utilizing {sup 99m}Tc-MAA lung perfusion, and predicted pulmonary function by means of the measured volumes. We examined the correlation between predicted and the measured values of postoperative pulmonary function, forced vital capacity (FVC) and forced expiratory volume in one second (FEV{sub 1.0}). The correlation between FEV{sub 1.0} predicted by SPECT (threshold 50%) and measured postoperative lung function resembled that between lung function predicted by the standard planar method and measured FEV{sub 1.0} in the lobectomy group. We then examined the ratios of both pre- and postoperative blood perfusion volumes obtained using 3-D imaging at lung perfusion threshold ranges of 10% each (PV20-29, PV30-39) to pre- and postoperative total perfusion (PV20-100). In the lobectomy group, the postoperative PV20-29/PV20-100 value was significantly higher for the operative side lung than the preoperative PV20-29/PV20-100 value, and the postoperative PV50-59, 60-69, 70-79, 80-89 and 90-100/PV20-100 values were significantly lower than the respective preoperative values. However, in the contralateral lung, the respective pre- and postoperative PV/PV20-100 values were almost identical. These findings suggest that the rate of low blood perfusion increased while the rate of middle to high perfusion decreased in the lobectomy group in the operative

  4. The lognormal perfusion model for disruption replenishment measurements of blood flow: in vivo validation.

    Science.gov (United States)

    Hudson, John M; Leung, Kogee; Burns, Peter N

    2011-10-01

    Dynamic contrast enhanced ultrasound (DCE-US) is evolving as a promising tool to noninvasively quantify relative tissue perfusion in organs and solid tumours. Quantification using the method of disruption replenishment is best performed using a model that accurately describes the replenishment of microbubble contrast agents through the ultrasound imaging plane. In this study, the lognormal perfusion model was validated using an exposed in vivo rabbit kidney model. Compared against an implanted transit time flow meter, longitudinal relative flow measurement was (×3) less variable and correlated better when quantification was performed with the lognormal perfusion model (Spearman r = 0.90, 95% confidence interval [CI] = 0.05) vs. the prevailing mono-exponential model (Spearman r = 0.54, 95% CI = 0.18). Disruption-replenishment measurements using the lognormal perfusion model were reproducible in vivo to within 12%.

  5. Can perfusion CT assessment of primary colorectal adenocarcinoma blood flow at staging predict for subsequent metastatic disease? A pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Goh, Vicky [Mount Vernon Hospital, Paul Strickland Scanner Centre, Northwood (United Kingdom); Halligan, Steve [University College Hospital, Department of Academic Radiology, London (United Kingdom); Wellsted, David M. [University of Hertfordshire, Health Research and Development Support Unit, Hatfield (United Kingdom); Bartram, Clive I. [St Mark' s Hospital, Intestinal Imaging Centre, Harrow (United Kingdom)

    2009-01-15

    We aimed to determine whether perfusion CT measurements at colorectal cancer staging may predict for subsequent metastatic relapse. Fifty two prospective patients underwent perfusion CT at staging to estimate tumour blood flow, blood volume, mean transit time, and permeability surface area product. Patients considered metastasis free and suitable for surgery underwent curative resection subsequently. At final analysis, a median of 48.6 months post-surgery, patients were divided into those who remained disease free, and those with subsequent metastases. Vascular parameters for these two groups were compared using t-testing, and receiver operator curve analysis was performed to determine the sensitivity and specificity of these vascular parameters for predicting metastases. Thirty seven (71%) patients underwent curative surgery; data were available for 35: 26 (74%) remained disease free; 9 (26%) recurred (8 metastatic, 1 local). Tumour blood flow differed significantly between disease-free and metastatic patients (76.0 versus 45.7 ml/min/100 g tissue; p=0.008). With blood flow <64 ml/min/100 g tissue, sensitivity and specificity (95% CI) for development of metastases were 100% (60-100%) and 73% (53-87%), respectively. Our preliminary findings suggest that primary tumour blood flow might potentially be a useful predictor warranting further study. (orig.)

  6. Cortical perfusion index: A predictor of acute rejection in transplanted kidneys

    Energy Technology Data Exchange (ETDEWEB)

    Atkins, H.L.; Oster, Z.H.; Anaise, D.; Wein, S.; Waltzer, W.; Gonder, A.; Cooch, E.; Rapaport, F.T.

    1985-05-01

    The presently available non-invasive methods for the diagnosis of acute rejection crisis (ARC) of renal transplants are not satisfactory. However, the need for such a test is of paramount clinical importance. A prospective study of 74 post-transplantation events in renal allograft recipients was performed. Clinical, surgical exploration and biopsy data were correlated with TC-99m DTPA scintigraphy using the following indices: Global perfusion index (GPI), cortical perfusion index (CPI), medullary perfusion index (MPI), the peak-to-plateau ratio (P/P), iliac artery peak to renal peak time (delta-P) and washout half-time (T1/2). Of the 74 events, 24 were proven to be due to acute rejection crisis (ARC), 13 were of ureteral obstruction, 18 various nephropathies and 19 in stable renal transplant function. The P/P, delta-P and T1/2 were not good predictors of ARC; the sensitivity was 79%, 79% and 80% respectively. The sensitivity of the GPI was 58% and the specificity was 87%. The cortical perfusion index rated better: specificity=84% and sensitivity=87%. However, the best indicator of ARC seemed to be the percent increase in cortical perfusion index over previous values obtained during stable graft function. Thus the sensitivity was found to be 91% and specificity was 96%. The difference between global and cortical perfusion indices reflects shunting of blood for cortex to medulla. This study suggest that the cortical perfusion index (CPI) and the percent increase in CPI can be used to non-invasively diagnose acute renal allograft rejection.

  7. Effects of Electroacupuncture Stimulation at “Zusanli” Acupoint on Hepatic NO Release and Blood Perfusion in Mice

    Directory of Open Access Journals (Sweden)

    Shu-you Wang

    2015-01-01

    Full Text Available The study is to observe the influence of electroacupuncture (EA stimulation at “Zusanli” (ST36 on the release of nitric oxide (NO and blood perfusion (BP in the liver and further explore whether the hepatic blood perfusion (HBP changes were regulated by EA ST36 induced NO in nitric oxide synthase inhibited mice. The HBP change of the mice was detected by laser speckle perfusion imaging (LSPI before and after being given interventions, and the NO in liver tissue was detected by nitric acid reductase in each group. The NO levels and HBP in the L-NAME group were significantly lower than those in the control group (P<0.01. The NO level and HBP increase in EA group were significantly higher than those in control group (P<0.05. The NO level in the L-NAME EA group was slightly higher than that in the L-NAME group. The HBP increase in the L-NAME EA group was not statistically significant. These results showed that EA could accelerate the synthesis of NO and thereby increase HBP via vasodilation in liver tissue.

  8. Effects of Electroacupuncture Stimulation at “Zusanli” Acupoint on Hepatic NO Release and Blood Perfusion in Mice

    Science.gov (United States)

    Wang, Shu-you; Zhang, Dong; Tang, Li-mei; Li, Shun-yue; Wen, Mei; Song, Xiao-jing

    2015-01-01

    The study is to observe the influence of electroacupuncture (EA) stimulation at “Zusanli” (ST36) on the release of nitric oxide (NO) and blood perfusion (BP) in the liver and further explore whether the hepatic blood perfusion (HBP) changes were regulated by EA ST36 induced NO in nitric oxide synthase inhibited mice. The HBP change of the mice was detected by laser speckle perfusion imaging (LSPI) before and after being given interventions, and the NO in liver tissue was detected by nitric acid reductase in each group. The NO levels and HBP in the L-NAME group were significantly lower than those in the control group (P < 0.01). The NO level and HBP increase in EA group were significantly higher than those in control group (P < 0.05). The NO level in the L-NAME EA group was slightly higher than that in the L-NAME group. The HBP increase in the L-NAME EA group was not statistically significant. These results showed that EA could accelerate the synthesis of NO and thereby increase HBP via vasodilation in liver tissue. PMID:25649678

  9. Dynamic Susceptibility Contrast Perfusion Magnetic Resonance Imaging Demonstrates Reduced Periventricular Cerebral Blood Flow in Dogs with Ventriculomegaly

    Directory of Open Access Journals (Sweden)

    Martin J. Schmidt

    2017-08-01

    Full Text Available The nature of ventriculomegaly in dogs is still a matter of debate. Signs of increased intraventricular pressure and atrophy of the cerebral white matter have been found in dogs with ventriculomegaly, which would imply increased intraventricular pressure and, therefore, a pathological condition, i.e., to some extent. Reduced periventricular blood flow was found in people with high elevated intraventricular pressure. The aim of this study was to compare periventricular brain perfusion in dogs with and without ventriculomegaly using perfusion weighted-magnetic-resonance-imaging to clarify as to whether ventriculomegaly might be associated with an increase in intraventricular pressure. Perfusion was measured in 32 Cavalier King Charles spaniels (CKCS with ventriculomegaly, 10 CKCSs were examined as a control group. Cerebral blood flow (CBF was measured using free-hand regions of interest (ROI in five brain regions: periventricular white matter, caudate nucleus, parietal cortex, hippocampus, and thalamus. CBF was significantly lower in the periventricular white matter of the dogs with ventriculomegaly (p = 0.0029 but not in the other ROIs. Reduction of periventricular CBF might imply increase of intraventricular pressure in ventriculomegaly.

  10. Carbon dioxide induced changes in cerebral blood flow and flow velocity: role of cerebrovascular resistance and effective cerebral perfusion pressure.

    Science.gov (United States)

    Grüne, Frank; Kazmaier, Stephan; Stolker, Robert J; Visser, Gerhard H; Weyland, Andreas

    2015-09-01

    In addition to cerebrovascular resistance (CVR) zero flow pressure (ZFP), effective cerebral perfusion pressure (CPPe) and the resistance area product (RAP) are supplemental determinants of cerebral blood flow (CBF). Until now, the interrelationship of PaCO2-induced changes in CBF, CVR, CPPe, ZFP, and RAP is not fully understood. In a controlled crossover trial, we investigated 10 anesthetized patients aiming at PaCO2 levels of 30, 37, 43, and 50 mm Hg. Cerebral blood flow was measured with a modified Kety-Schmidt-technique. Zero flow pressure and RAP was estimated by linear regression analysis of pressure-flow velocity relationships of the middle cerebral artery. Effective cerebral perfusion pressure was calculated as the difference between mean arterial pressure and ZFP, CVR as the ratio CPPe/CBF. Statistical analysis was performed by one-way RM-ANOVA. When comparing hypocapnia with hypercapnia, CBF showed a significant exponential reduction by 55% and mean VMCA by 41%. Effective cerebral perfusion pressure linearly decreased by 17% while ZFP increased from 14 to 29 mm Hg. Cerebrovascular resistance increased by 96% and RAP by 39%; despite these concordant changes in mean CVR and Doppler-derived RAP correlation between these variables was weak (r=0.43). In conclusion, under general anesthesia hypocapnia-induced reduction in CBF is caused by both an increase in CVR and a decrease in CPPe, as a consequence of an increase in ZFP.

  11. Non-invasive prenatal paternity testing from maternal blood.

    Science.gov (United States)

    Wagner, Jasenka; Dzijan, Snjezana; Marjanović, Damir; Lauc, Gordan

    2009-01-01

    Prenatal paternity analysis can be performed only after invasive sampling of chorionic villi or amnionic fluid. Aiming to enable noninvasive paternity testing, we attempted to amplify fetal alleles from maternal plasma. Cell-free DNA was isolated from plasma of 20 pregnant women and amplified with ampFLSTR Identifiler and ampFLSTR Yfiler kits. Unfortunately, autosomal fetal alleles were heavily suppressed by maternal DNA, and the only locus that was reliably amplified with AmpFLSTR Identifiler kit was amelogenin, which revealed only fetal gender. Much better success was obtained with AmpFLSTR Yfiler kit, which, in the case of male fetuses, successfully amplified between six and 16 fetal loci. All amplified fetal alleles matched the alleles of their putative fathers, confirming the tested paternity. To the best of our knowledge, this is a first report of noninvasive prenatal paternity testing.

  12. Non-invasive Estimation of Pressure Gradients in Pulsatile Flow using Ultrasound

    DEFF Research Database (Denmark)

    Olesen, Jacob Bjerring; Villagómez Hoyos, Carlos Armando; Traberg, Marie Sand

    2014-01-01

    This paper investigates how pressure gradients in a pulsatile flow environment can be measured non-invasively using ultrasound. The presented set-up is based on vector velocity fields measured on a blood mimicking fluid moving at a peak flow rate of 1 ml/s through a constricted vessel. Fields of ...... and standard deviation of 10% and 13%, respectively, relative to peak estimated gradient. The paper concludes that maps of pressure gradients can be measured non-invasively using ultrasound with a precision of more than 85%......This paper investigates how pressure gradients in a pulsatile flow environment can be measured non-invasively using ultrasound. The presented set-up is based on vector velocity fields measured on a blood mimicking fluid moving at a peak flow rate of 1 ml/s through a constricted vessel. Fields...... of pressure gradients are calculated using the Navier-Stokes equations. Flow data are acquired to a depth of 3 cm using directional synthetic aperture flow imaging on a linear array transducer producing 1500 image frames of velocity estimates per second. Scans of a carotid bifurcation phantom with a 70...

  13. Effects of Dynamic Changes in Ultrasound Attenuation and Blood Perfusion on Lesion Formation of Multiple focus Pattern during Ultrasound Surgery

    Institute of Scientific and Technical Information of China (English)

    ZHANG Chen-xi; BAI Jing-feng; CHEN Ya-zhu

    2007-01-01

    A nonlinear finite-element program was developed to simulate the dynamic evolution of coagulation in tissue considering temperature and thermal-dose dependence of the ultrasound attenuation and blood perfusion rate.The effects of these dynamic parameters on the lesion formation were investigated in the particular case of ultrasound hepatic ablation with bi-focus intensity pattern.The results of simulations were compared that incorporate dynamic changes of ultrasound attenuation and perfusion and results that neglect these effects.The result shows that thermal-dose-dependent ultrasound attenuation is the dominating factor in the full dynamic model.If the dynamic ultrasound attenuation is ignored, a relatively significant underestimation of the temperature rise appears in the focal plane and the region next to the focal plane, resulting in an underestimation in predicting diameter of coagulation.Higher heating intensity leads to greater underestimation.

  14. Blood perfusion values of laser speckle contrast imaging and laser Doppler flowmetry: is a direct comparison possible?

    Science.gov (United States)

    Binzoni, Tiziano; Humeau-Heurtier, Anne; Abraham, Pierre; Mahe, Guillaume

    2013-05-01

    Laser Doppler flowmetry (LDF) and laser speckle contrast imaging (LSCI) allow the monitoring of microvascular blood perfusion. The relationship between the measurements obtained by these two techniques remains unclear. In the present contribution, we demonstrate, experimentally and theoretically, that skin blood flow measurements obtained by LDF and LSCI techniques cannot be compared directly even after "classical" normalization procedure. This technical problem is generated by the nonlinear relationship existing between LDF and LSCI flow data. The experiments have been performed on five healthy voluntary subjects (forearm) by using repeated ischemia/reperfusion cycles to induce the necessary skin blood flow changes. LDF and LSCI data were simultaneously acquired on the same region of interest. Considering the importance of this problem from the clinical point of view, it is concluded that the definition of new corrected algorithms for LSCI is probably a mandatory step that must be taken into account if LDF and LSCI blood flow have to be compared.

  15. TIPS bilateral noise reduction in 4D CT perfusion scans produces high-quality cerebral blood flow maps

    Energy Technology Data Exchange (ETDEWEB)

    Mendrik, Adrienne M; Van Ginneken, Bram; Viergever, Max A [Image Sciences Institute, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht (Netherlands); Vonken, Evert-jan; De Jong, Hugo W; Riordan, Alan; Van Seeters, Tom; Smit, Ewoud J; Prokop, Mathias, E-mail: a.m.mendrik@gmail.com [Radiology Department, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht (Netherlands)

    2011-07-07

    Cerebral computed tomography perfusion (CTP) scans are acquired to detect areas of abnormal perfusion in patients with cerebrovascular diseases. These 4D CTP scans consist of multiple sequential 3D CT scans over time. Therefore, to reduce radiation exposure to the patient, the amount of x-ray radiation that can be used per sequential scan is limited, which results in a high level of noise. To detect areas of abnormal perfusion, perfusion parameters are derived from the CTP data, such as the cerebral blood flow (CBF). Algorithms to determine perfusion parameters, especially singular value decomposition, are very sensitive to noise. Therefore, noise reduction is an important preprocessing step for CTP analysis. In this paper, we propose a time-intensity profile similarity (TIPS) bilateral filter to reduce noise in 4D CTP scans, while preserving the time-intensity profiles (fourth dimension) that are essential for determining the perfusion parameters. The proposed TIPS bilateral filter is compared to standard Gaussian filtering, and 4D and 3D (applied separately to each sequential scan) bilateral filtering on both phantom and patient data. Results on the phantom data show that the TIPS bilateral filter is best able to approach the ground truth (noise-free phantom), compared to the other filtering methods (lowest root mean square error). An observer study is performed using CBF maps derived from fifteen CTP scans of acute stroke patients filtered with standard Gaussian, 3D, 4D and TIPS bilateral filtering. These CBF maps were blindly presented to two observers that indicated which map they preferred for (1) gray/white matter differentiation, (2) detectability of infarcted area and (3) overall image quality. Based on these results, the TIPS bilateral filter ranked best and its CBF maps were scored to have the best overall image quality in 100% of the cases by both observers. Furthermore, quantitative CBF and cerebral blood volume values in both the phantom and the

  16. TIPS bilateral noise reduction in 4D CT perfusion scans produces high-quality cerebral blood flow maps

    Science.gov (United States)

    Mendrik, Adriënne M.; Vonken, Evert-jan; van Ginneken, Bram; de Jong, Hugo W.; Riordan, Alan; van Seeters, Tom; Smit, Ewoud J.; Viergever, Max A.; Prokop, Mathias

    2011-07-01

    Cerebral computed tomography perfusion (CTP) scans are acquired to detect areas of abnormal perfusion in patients with cerebrovascular diseases. These 4D CTP scans consist of multiple sequential 3D CT scans over time. Therefore, to reduce radiation exposure to the patient, the amount of x-ray radiation that can be used per sequential scan is limited, which results in a high level of noise. To detect areas of abnormal perfusion, perfusion parameters are derived from the CTP data, such as the cerebral blood flow (CBF). Algorithms to determine perfusion parameters, especially singular value decomposition, are very sensitive to noise. Therefore, noise reduction is an important preprocessing step for CTP analysis. In this paper, we propose a time-intensity profile similarity (TIPS) bilateral filter to reduce noise in 4D CTP scans, while preserving the time-intensity profiles (fourth dimension) that are essential for determining the perfusion parameters. The proposed TIPS bilateral filter is compared to standard Gaussian filtering, and 4D and 3D (applied separately to each sequential scan) bilateral filtering on both phantom and patient data. Results on the phantom data show that the TIPS bilateral filter is best able to approach the ground truth (noise-free phantom), compared to the other filtering methods (lowest root mean square error). An observer study is performed using CBF maps derived from fifteen CTP scans of acute stroke patients filtered with standard Gaussian, 3D, 4D and TIPS bilateral filtering. These CBF maps were blindly presented to two observers that indicated which map they preferred for (1) gray/white matter differentiation, (2) detectability of infarcted area and (3) overall image quality. Based on these results, the TIPS bilateral filter ranked best and its CBF maps were scored to have the best overall image quality in 100% of the cases by both observers. Furthermore, quantitative CBF and cerebral blood volume values in both the phantom and the

  17. Utility of Transcutaneous Capnography for Optimization of Non-Invasive Ventilation Pressures.

    Science.gov (United States)

    Chhajed, Prashant N; Gehrer, Simone; Pandey, Kamlesh V; Vaidya, Preyas J; Leuppi, Joerg D; Tamm, Michael; Strobel, Werner

    2016-09-01

    Nocturnal Non-invasive Positive Pressure Ventilation (NPPV) is the treatment of choice in patients with chronic hypercapnic respiratory failure due to hypoventilation. Continuous oxygen saturation measured with a pulse oximeter provides a surrogate measure of arterial oxygen saturation but does not completely reflect ventilation. Currently, Partial Pressure of Arterial (PaCO2) measured by arterial blood analysis is used for estimating the adequacy of ventilatory support and serves as the gold standard. To examine the safety, feasibility and utility of cutaneous capnography to re-titrate the non-invasive positive pressure ventilation settings in patients with chronic hypercapnic respiratory failure due to hypoventilation. Twelve patients with chronic hypercapnic respiratory failure prospectively underwent complete polysomnography and cutaneous capnography measurement on the ear lobe. Non-invasive ventilation pressures were adjusted with the aim of normalizing cutaneous carbon dioxide or at least reducing it by 10 to 15 mmHg. Sensor drift for cutaneous carbon dioxide of 0.7 mmHg per hour was integrated in the analysis. Mean baseline cutaneous carbon dioxide was 45.4 ± 6.5 mmHg and drift corrected awake value was 45.1 ± 8.3 mmHg. The correlation of baseline cutaneous carbon dioxide and the corrected awake cutaneous carbon dioxide with arterial blood gas values were 0.91 and 0.85 respectively. Inspiratory positive airway pressures were changed in nine patients (75%) and expiratory positive airway pressures in eight patients (66%). Epworth sleepiness score before and after the study showed no change in five patients, improvement in six patients and deterioration in one patient. Cutaneous capnography is feasible and permits the optimization of non-invasive ventilation pressure settings in patients with chronic hypercapnic respiratory failure due to hypoventilation. Continuous cutaneous capnography might serve as an important additional tool to complement diurnal

  18. Non-invasive mechanic ventilation in treating acute respiratory failure

    Directory of Open Access Journals (Sweden)

    Federico Lari

    2009-12-01

    Full Text Available Non invasive ventilation (NIV in acute respiratory failure (ARF improve clinical parameters, arterial blood gases, decrease mortality and endo tracheal intubation (ETI rate also outside the intensive care units (ICUs. Objective of this study is to verify applicability of NIV in a general non respiratory medical ward. We enrolled 68 consecutive patients (Pts with Hypoxemic or Hyper capnic ARF: acute cardiogenic pulmonary edema (ACPE, exacerbation of chronic obstructive pulmonary disease (COPD, Pneu - monia, acute lung injury / acute respiratory distress syndrome (ALI/ARDS. NIV treatment was CPAP or PSV + PEEP. 12 Pts (18,5% met primary endpoint (NIV failure: 11 Pts (17% needed ETI (5ALI/ARDS p < 0,0001, 6COPD 16,6%, 1 Patient (1,5% died (Pneumonia. No Pts with ACPE failed (p = 0,0027. Secondary endpoints: significant improvement in Respiratory Rate (RR, Kelly Score, pH, PaCO2, PaO2 vs baseline. Median duration of treatment: 16:06 hours: COPD 18:54, ACPE 4:15. Mean length of hospitalisation: 8.66 days. No patients discontinued NIV, no side effects. Results are consistent with literature. Hypoxemic ARF related to ALI/ARDS and pneumonia show worst outcome: it is not advisable to manage these conditions with NIV outside the ICU. NIV for ARF due to COPD and ACPE is feasible, safe and effective in a general medical ward if selection of Pts, staff’s training and monitoring are appropriate. This should encourage the diffusion of NIV in this specific setting. According to strong evidences in literature, NIV should be considered a first line and standard treatment in these clinical conditions irrespective of the setting.

  19. Linking non-invasive parametric MRI with invasive physiological measurements (MR-PHYSIOL): towards a hybrid and integrated approach for investigation of acute kidney injury in rats.

    Science.gov (United States)

    Pohlmann, A; Cantow, K; Hentschel, J; Arakelyan, K; Ladwig, M; Flemming, B; Hoff, U; Persson, P B; Seeliger, E; Niendorf, T

    2013-04-01

    Acute kidney injury of various origins shares a common link in the pathophysiological chain of events: imbalance between renal medullary oxygen delivery and oxygen demand. For in vivo assessment of kidney haemodynamics and oxygenation in animals, quantitative but invasive physiological methods are established. A very limited number of studies attempted to link these invasive methods with parametric Magnetic Resonance Imaging (MRI) of the kidney. Moreover, the validity of parametric MRI (pMRI) as a surrogate marker for renal tissue perfusion and renal oxygenation has not been systematically examined yet. For this reason, we set out to combine invasive techniques and non-invasive MRI in an integrated hybrid setup (MR-PHYSIOL) with the ultimate goal to calibrate, monitor and interpret parametric MR and physiological parameters by means of standardized interventions. Here we present a first report on the current status of this multi-modality approach. For this purpose, we first highlight key characteristics of renal perfusion and oxygenation. Second, concepts for in vivo characterization of renal perfusion and oxygenation are surveyed together with the capabilities of MRI for probing blood oxygenation-dependent tissue stages. Practical concerns evoked by the use of strong magnetic fields in MRI and interferences between MRI and invasive physiological probes are discussed. Technical solutions that balance the needs of in vivo physiological measurements together with the constraints dictated by small bore MR scanners are presented. An early implementation of the integrated MR-PHYSIOL approach is demonstrated including brief interventions of hypoxia and hyperoxia. Acta Physiologica © 2013 Scandinavian Physiological Society.

  20. State-of-the-Art Sensor Technology in Spain: Invasive and Non-Invasive Techniques for Monitoring Respiratory Variables

    Directory of Open Access Journals (Sweden)

    Christian Domingo

    2010-05-01

    Full Text Available The interest in measuring physiological parameters (especially arterial blood gases has grown progressively in parallel to the development of new technologies. Physiological parameters were first measured invasively and at discrete time points; however, it was clearly desirable to measure them continuously and non-invasively. The development of intensive care units promoted the use of ventilators via oral intubation ventilators via oral intubation and mechanical respiratory variables were progressively studied. Later, the knowledge gained in the hospital was applied to out-of-hospital management. In the present paper we review the invasive and non-invasive techniques for monitoring respiratory variables.

  1. Long-term pressure monitoring with arterial applanation tonometry : a non-invasive alternative during clinical intervention?

    NARCIS (Netherlands)

    Matthys, Koen S; Kalmar, Alain F; Struys, Michel M R F; Mortier, Eric P; Avolio, Alberto P; Segers, Patrick; Verdonck, Pascal R

    2008-01-01

    Arterial tonometry is a non-invasive technique for continuous registration of arterial pressure waveforms. This study aims to assess tonometric blood pressure recording (TBP) as an alternative for invasive long-term bedside monitoring. A prospective study was set up where patients undergoing neurosu

  2. Non-medical applications of non invasive prenatal testing: ethical issues and apllicabilities

    OpenAIRE

    Tasinato, Paola

    2013-01-01

    The possibility of obtaining material for foetal molecular analysis without the need of invasive procedures has been a long wished improvement of practice in prenatal diagnostics. The demonstration of the presence of foetal cells and circulating foetal free-DNA in a sample of mother-to-be’s blood promised that a non-invasive approach for prenatal diagnostics is near to becoming a reality. The presence of foetal cells (albeit in low numbers) in maternal blood has been known since 1893, when...

  3. Dose reduction in dynamic perfusion CT of the brain: effects of the scan frequency on measurements of cerebral blood flow, cerebral blood volume, and mean transit time

    Energy Technology Data Exchange (ETDEWEB)

    Wiesmann, Martin [University of Munich, Department of Neuroradiology, Muenchen (Germany); Klinikum der Universitaet Muenchen - Grosshadern, Abteilung fuer Neuroradiologie, Muenchen (Germany); Berg, Scott; Stoeckelhuber, B.M. [University of Luebeck, Department of Radiology, Luebeck (Germany); Bohner, G.; Klingebiel, R. [University Medicine Berlin, Department of Neuroradiology, Charite, Berlin (Germany); Schoepf, V.; Yousry, I.; Linn, J. [University of Munich, Department of Neuroradiology, Muenchen (Germany); Missler, U. [Evangelisches Krankenhaus Duisburg-Nord, Department of Neuroradiology, Duisburg (Germany)

    2008-12-15

    The influence of the frequency of computed tomography (CT) image acquistion on the diagnostic quality of dynamic perfusion CT (PCT) studies of the brain was investigated. Eight patients with clinically suspected acute ischemia of one hemisphere underwent PCT, performed on average 3.4 h after the onset of symptoms. Sixty consecutive images per slice were obtained with individual CT images obtained at a temporal resolution of two images per second. Eight additional data sets were reconstructed with temporal resolutions ranging from one image per second to one image per 5 s. Cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) measurements were performed in identical regions of interest. Two neuroradiologists evaluated the PCT images visually to identify areas of abnormal perfusion. Perfusion images created up to a temporal resolution of one image per 3 s were rated to be diagnostically equal to the original data. Even at one image per 4 s, all areas of infarction were identified. Quantitative differences of CBF, CBV and MTT measurements were {<=}10% up to one image per 3 s. For PCT of the brain, temporal resolution can be reduced to one image per 3 s without significant compromise in image quality. This significantly reduces the radiation dose of the patient. (orig.)

  4. Blood perfusion in osteomyelitis studied with [(15)O]water PET in a juvenile porcine model

    DEFF Research Database (Denmark)

    Jødal, Lars; Nielsen, Ole L; Afzelius, Pia;

    2017-01-01

    BACKGROUND: Osteomyelitis is a serious disease which can be difficult to treat despite properly instituted antibiotic therapy. This appears to be related at least partly to degraded vascularisation in the osteomyelitic (OM) lesions. Studies of perfusion in OM bones are, however, few and not quant......BACKGROUND: Osteomyelitis is a serious disease which can be difficult to treat despite properly instituted antibiotic therapy. This appears to be related at least partly to degraded vascularisation in the osteomyelitic (OM) lesions. Studies of perfusion in OM bones are, however, few...... that perfusion will be less elevated in OM lesions than in soft tissue (ST) infection. The study comprised 11 juvenile pigs with haematogenous osteomyelitis induced by injection of Staphylococcus aureus into the right femoral artery 1 week before scanning (in one pig, 2 weeks). The pigs were dynamically PET...

  5. Non-Invasive Glucose Measurement by Use of Metabolic Heat Conformation Method

    Directory of Open Access Journals (Sweden)

    Junfeng Li

    2008-05-01

    Full Text Available A non-invasive glucose measurement system based on the method of metabolic heat conformation (MHC is presented in this paper. This system consists of three temperature sensors, two humidity sensors, an infrared sensor and an optical measurement device. The glucose level can be deduced from the quantity of heat dissipation, blood flow rate of local tissue and degree of blood oxygen saturation. The methodology of the data process and the measurement error are also analyzed. The system is applied in a primary clinical test. Compared with the results of a commercial automated chemistry analyzer, the correlation coefficient of the collected data from the system is 0.856. Result shows that the correlation coefficient improves when the factor of heat dissipated by evaporation of the skin is added in. A non-invasive method of measuring the blood flow rate of local tissue by heat transmission between skin and contacted conductor is also introduced. Theoretical derivation and numerical simulation are completed as well. The so-called normalized difference mean (NDM is chosen to express the quantity of the blood flow rate. The correlation coefficient between the blood flow rates by this method and the results of a Doppler blood flow meter is equal to 0.914.

  6. Non-Invasive Glucose Measurement by Use of Metabolic Heat Conformation Method.

    Science.gov (United States)

    Tang, Fei; Wang, Xiaohao; Wang, Dongsheng; Li, Junfeng

    2008-05-21

    A non-invasive glucose measurement system based on the method of metabolic heat conformation (MHC) is presented in this paper. This system consists of three temperature sensors, two humidity sensors, an infrared sensor and an optical measurement device. The glucose level can be deduced from the quantity of heat dissipation, blood flow rate of local tissue and degree of blood oxygen saturation. The methodology of the data process and the measurement error are also analyzed. The system is applied in a primary clinical test. Compared with the results of a commercial automated chemistry analyzer, the correlation coefficient of the collected data from the system is 0.856. Result shows that the correlation coefficient improves when the factor of heat dissipated by evaporation of the skin is added in. A non-invasive method of measuring the blood flow rate of local tissue by heat transmission between skin and contacted conductor is also introduced. Theoretical derivation and numerical simulation are completed as well. The so-called normalized difference mean (NDM) is chosen to express the quantity of the blood flow rate. The correlation coefficient between the blood flow rates by this method and the results of a Doppler blood flow meter is equal to 0.914.

  7. Non-invasive brain stimulation in early rehabilitation after stroke.

    Science.gov (United States)

    Blesneag, A V; Popa, L; Stan, A D

    2015-01-01

    The new tendency in rehabilitation involves non-invasive tools that, if applied early after stroke, promote neurorecovery. Repetitive transcranial magnetic stimulation and transcranial direct current stimulation may correct the disruption of cortical excitability and effectively contribute to the restoration of movement and speech. The present paper analyses the results of non-invasive brain stimulation (NIBS) trials, highlighting different aspects related to the repetitive transcranial magnetic stimulation frequency, transcranial direct current stimulation polarity, the period and stimulation places in acute and subacute ischemic strokes. The risk of adverse events, the association with motor or language recovery specific training, and the cumulative positive effect evaluation are also discussed.

  8. Perfusion MRI (dynamic susceptibility contrast imaging) with different measurement approaches for the evaluation of blood flow and blood volume in human gliomas

    Energy Technology Data Exchange (ETDEWEB)

    Thomsen, H. (Den Sundhedsfaglige Kandidatuddannelse, Aarhus Universitet Bygning 1264, Aarhus (Denmark); University College Nordjylland, Aalborg (Denmark)), Email: hnt@ucn.dk; Steffensen, E. (Aalborg Hospital/Aarhus University Hospital, Department of Radiology, Aalborg (Denmark)); Larsson, E. M. (Aalborg Hospital/Aarhus University Hospital, Department of Radiology, Aalborg (Denmark); Uppsala University Hospital, Department of Radiology, Uppsala (Sweden))

    2012-02-15

    Background. Perfusion magnetic resonance imaging (MRI) is increasingly used in the evaluation of brain tumors. Relative cerebral blood volume (rCBV) is usually obtained by dynamic susceptibility contrast (DSC) MRI using normal appearing white matter as reference region. The emerging perfusion technique arterial spin labelling (ASL) presently provides measurement only of cerebral blood flow (CBF), which has not been widely used in human brain tumor studies. Purpose. To assess if measurement of blood flow is comparable with measurement of blood volume in human biopsy-proven gliomas obtained by DSC-MRI using two different regions for normalization and two different measurement approaches. Material and Methods. Retrospective study of 61 patients with different types of gliomas examined with DSC perfusion MRI. Regions of interest (ROIs) were placed in tumor portions with maximum perfusion on rCBF and rCBV maps, with contralateral normal appearing white matter and cerebellum as reference regions. Larger ROIs were drawn for histogram analyses. The type and grade of the gliomas were obtained by histopathology. Statistical comparison was made between diffuse astrocytomas, anaplastic astrocytomas, and glioblastomas. Results. rCBF and rCBV measurements obtained with the maximum perfusion method were correlated when normalized to white matter (r = 0.60) and to the cerebellum (r = 0.49). Histogram analyses of rCBF and rCBV showed that mean and median values as well as skewness and peak position were correlated (0.61 < r < 0.93), whereas for kurtosis and peak height, the correlation coefficient was about 0.3 when comparing rCBF and rCBV values for the same reference region. Neither rCBF nor rCBV quantification provided a statistically significant difference between the three types of gliomas. However, both rCBF and rCBV tended to increase with tumor grade and to be lower in patients who had undergone resection/treatment. Conclusion. rCBF measurements normalized to white matter

  9. Comparison of blood flow models and acquisitions for quantitative myocardial perfusion estimation from dynamic CT

    Science.gov (United States)

    Bindschadler, Michael; Modgil, Dimple; Branch, Kelley R.; La Riviere, Patrick J.; Alessio, Adam M.

    2014-04-01

    Myocardial blood flow (MBF) can be estimated from dynamic contrast enhanced (DCE) cardiac CT acquisitions, leading to quantitative assessment of regional perfusion. The need for low radiation dose and the lack of consensus on MBF estimation methods motivates this study to refine the selection of acquisition protocols and models for CT-derived MBF. DCE cardiac CT acquisitions were simulated for a range of flow states (MBF = 0.5, 1, 2, 3 ml (min g)-1, cardiac output = 3, 5, 8 L min-1). Patient kinetics were generated by a mathematical model of iodine exchange incorporating numerous physiological features including heterogenenous microvascular flow, permeability and capillary contrast gradients. CT acquisitions were simulated for multiple realizations of realistic x-ray flux levels. CT acquisitions that reduce radiation exposure were implemented by varying both temporal sampling (1, 2, and 3 s sampling intervals) and tube currents (140, 70, and 25 mAs). For all acquisitions, we compared three quantitative MBF estimation methods (two-compartment model, an axially-distributed model, and the adiabatic approximation to the tissue homogeneous model) and a qualitative slope-based method. In total, over 11 000 time attenuation curves were used to evaluate MBF estimation in multiple patient and imaging scenarios. After iodine-based beam hardening correction, the slope method consistently underestimated flow by on average 47.5% and the quantitative models provided estimates with less than 6.5% average bias and increasing variance with increasing dose reductions. The three quantitative models performed equally well, offering estimates with essentially identical root mean squared error (RMSE) for matched acquisitions. MBF estimates using the qualitative slope method were inferior in terms of bias and RMSE compared to the quantitative methods. MBF estimate error was equal at matched dose reductions for all quantitative methods and range of techniques evaluated. This suggests that

  10. Characteristic patterns of cerebral blood perfusion and cognitive impairment in patients with Parkinsons disease

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Y. J.; Park, M. J.; Cha, J. G.; Kim, S. H.; Kim, J. W.; Kang, D. Y. [Dong-A University College of medicine, Pusan (Korea, Republic of)

    2005-07-01

    Parkinsons disease (PD) is a neurodegenerative disorder that represents cognitive impairment as well as motor symptoms. Even in the early stages of PD, cognitive alterations can be demonstrated by careful neuropsychological test. The purposes of this study are to investigate the pattern of cognitive impairment and the regional cerebral blood flow (rCBF) using Tc-99m HMPAO SPECT in patients with PD. One hundred and twenty two patients with PD and 35 control subjects participated in this study. Patients with PD who had dementia clinically or K-MMSE score below 25 points or with severe motor dysfunction to interfere with the tests were also excluded. They were all matched for age (61{+-}10 vs 61{+-}8), education periods (8.8{+-}4.9 vs 8.8{+-}4.5), and K-MMSE score (27{+-}1.6 vs 27{+-}1.5). All subjects were evaluated using the Seoul Neuropsychological Screening Battery (SNSB) and Tc-99m HMPAO SPECT with SPM software to measure rCBF. Patients with PD performed worse in digit span backward, Rey Complex Figure Test, visual memory, semantic fluency, stroop test, and alternating hand movement test(p<0.05) compared with control group. On SNSB test, 100 patients (82.0%) showed some abnormalities. Eighty-six patients (70.5%) showed frontal dysfunction, 47 (38.5%) memory impairment, 33 (27.0%) language dysfunction, 25 (20.5%) attention deficit and 22 (18.3%) visuospatial dysfunction in the order of frequency. Eight patients with PD showed single memory domain MCI and 28 single non-memory domain MCI (20 frontal dysfunction). Multiple domain MCI was found in 64 patients with PD. SPM analysis of the SPECT image revealed multiple perfusion deficit in the both frontal, temporal, both limbic lobes, Lt. parietal and Lt. Putamen. It is concluded that abnormalities of cognitive function be detected very commonly in patients with PD. MCI in PD patients is most frequently involved in the item of frontal lobe function. SPECT image might be helpful to explain cognitive impairment in some

  11. Dynamic subcortical blood flow during male sexual activity with ecological validity: a perfusion fMRI study.

    Science.gov (United States)

    Georgiadis, Janniko R; Farrell, Michael J; Boessen, Ruud; Denton, Derek A; Gavrilescu, Maria; Kortekaas, Rudie; Renken, Remco J; Hoogduin, Johannes M; Egan, Gary F

    2010-03-01

    This study used arterial spin labeling (ASL) fMRI to measure brain perfusion in a group of healthy men under conditions that closely resembled customary sexual behavior. Serial perfusion measures for 30 min during two self-limited periods of partnered penis stimulation, and during post-stimulatory periods, revealed novel sexual activity-related cerebral blood flow (rCBF) changes, mainly in subcortical parts of the brain. Ventral pallidum rCBF was highest during the onset of penile erection, and lowest after the termination of penis stimulation. The perceived level of sexual arousal showed the strongest positive association with rCBF in the right basal forebrain. In addition, our results demonstrate that distinct subregions of the hypothalamus and cingulate cortex subserve opposite functions during human male sexual behavior. The lateral hypothalamus and anterior part of the middle cingulate cortex showed increased rCBF correlated with penile erection. By contrast, the anteroventral hypothalamus and subgenual anterior cingulate cortex exhibited rCBF changes correlated with penile detumescence after penile stimulation. Continuous rapid and high-resolution brain perfusion imaging during normal sexual activity has provided novel insights into the central mechanisms that control male sexual arousal. Copyright (c) 2009 Elsevier Inc. All rights reserved.

  12. Prediction of oesophageal varices in patients with primary biliary cirrhosis by non-invasive markers

    Science.gov (United States)

    Gao, Lili; Li, Hanwei; Han, Jun; Zhang, Weihui

    2017-01-01

    Introduction Preliminary data suggested that non-invasive methods could be useful to assess presence of oesophageal varices (OV) in liver cirrhosis. The primary objectives were to investigate non-invasive markers for diagnosing and grading OV in patients with primary biliary cirrhosis. Material and methods This study included a total of 106 consecutive treatment-naive patients with primary biliary cirrhosis (PBC). Results of physical examination, blood tests, and abdominal ultrasound scan (USS) were measured. Performance of non-invasive markers for OV was expressed as sensitivity, specificity, positive, and negative predictive values (PPV, NPV), accuracy, and area under the curve (AUC). Results Oesophageal varices were found in 54 (50.9%) and large OV in 28 of the 106 patients. Variables found to differ significantly between patients with any grade or large and without OV included increased spleen length, increased portal vein diameter, low platelet count, and low levels of albumin or low γ-glutamyltranspeptidase (γ-GTP) values. Area under the receiver operating characteristic curve showed that spleen length (cutoff = 156.0) had AUC 0.753 (95% CI: 0.657–0.849), and high NPV (82.1%) to exclude any grade OV. Large OV could be excluded with NPV 70.6% by spleen length. Conclusions Predictive risk factors that use readily available laboratory results and ultrasound scan results may reliably identify esophageal varices in patients with PBC. PMID:28261290

  13. Assessment of lung function using a non-invasive oscillating gas-forcing technique.

    Science.gov (United States)

    Clifton, Lei; Clifton, David A; Hahn, Clive E W; Farmery, Andrew D

    2013-10-01

    Conventional methods for monitoring lung function can require complex, or special, gas analysers, and may therefore not be practical in clinical areas such as the intensive care unit (ICU) or operating theatre. The system proposed in this article is a compact and non-invasive system for the measurement and monitoring of lung variables, such as alveolar volume, airway dead space, and pulmonary blood flow. In contrast with conventional methods, the compact apparatus and non-invasive nature of the proposed method could eventually allow it to be used in the ICU, as well as in general clinical settings. We also propose a novel tidal ventilation model using a non-invasive oscillating gas-forcing technique, where both nitrous oxide and oxygen are used as indicator gases. Experimental results are obtained from healthy volunteers, and are compared with those obtained using a conventional continuous ventilation model. Our findings show that the proposed technique can be used to assess lung function, and has several advantages over conventional methods such as compact and portable apparatus, easy usage, and quick estimation of cardiopulmonary variables.

  14. Perfusion Linearity and Its Applications

    CERN Document Server

    Pianykh, Oleg

    2010-01-01

    Perfusion analysis computes blood flow parameters (blood volume, blood flow, mean transit time) from the observed flow of contrast agent, passing through the patient's vascular system. Perfusion deconvolution has been widely accepted as the principal numerical tool for perfusion analysis, and is used routinely in clinical applications. This extensive use of perfusion in clinical decision-making makes numerical stability and robustness of perfusion computations vital for accurate diagnostics and patient safety. The main goal of this paper is to propose a novel approach for validating numerical properties of perfusion algorithms. The approach is based on Perfusion Linearity Property (PLP), which we find in perfusion deconvolution, as well as in many other perfusion techniques. PLP allows one to study perfusion values as weighted averages of the original imaging data. This, in turn, uncovers hidden problems with the existing deconvolution techniques, and may be used to suggest more reliable computational approac...

  15. Thyroid perfusion imaging as a diagnostic tool in Graves' disease. Arterial spin labeling magnetic resonance imaging vs. colour-coded Doppler ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Muessig, K. [University Hospital of Duesseldorf (Germany). Dept. of Metabolic Diseases; Leibniz Center for Diabetes Research, Duesseldorf (Germany). Inst. for Clinical Diabetology; University Hospital of Tuebingen (Germany). Div. of Endocrinology, Diabetes, Nephrology, Angiology, and Clinical Chemistry; Schraml, C.; Schwenzer, N.F. [University Hospital of Tuebingen (Germany). Dept. of Radiology, Section on Experimental Radiology; University Hospital of Tuebingen (Germany). Dept. of Radiology, Diagnostic and Interventional Radiology; Rietig, R.; Balletshofer, B. [University Hospital of Tuebingen (Germany). Div. of Endocrinology, Diabetes, Nephrology, Angiology, and Clinical Chemistry; Martirosian, P.; Haering, H.U.; Schick, F. [University Hospital of Tuebingen (Germany). Dept. of Radiology, Section on Experimental Radiology; Claussen, C.D. [University Hospital of Tuebingen (Germany). Dept. of Radiology, Diagnostic and Interventional Radiology

    2012-12-15

    Purpose: Though increased thyroid perfusion assessed by colour-coded Doppler ultrasound (CDUS) is characteristic of Graves' disease (GD), sometimes perfusion assessment by CDUS is not possible. In these cases, arterial spin labelling (ASL), a novel magnetic resonance imaging (MRI) technique allowing non-invasive thyroid perfusion quantification, may have additional diagnostic value. We aimed to evaluate the potential of ASL-MRI for assessment of increased blood perfusion in patients with GD compared to CDUS. Materials and Methods: Thyroid perfusion was measured by CDUS (volume flow rate calculated from pulsed wave Doppler signals and vessel diameter) and ASL-MRI at 1.5 T in 7 patients with GD and 10 healthy controls. Results: In patients with GD, average perfusion in both thyroid lobes was markedly increased compared to controls. Both techniques applied for volume related perfusion as well as absolute volume flow in thyroid feeding vessels provided similar results (all p = 0.0008). Using a cut-off value of 22 ml/min for the volume flow rate assessed by CDUS in the four feeding vessels allowed discrimination between patients with GD and controls in all cases. After adjusting thyroid perfusion for the differences in organ volume, both CDUS and ASL revealed also complete discrimination between health and disease. Conclusion: Thyroid perfusion measurement by ASL-MRI reliably discriminate GD from normal thyroid glands. In patients in whom thyroid arteries cannot be depicted by CDUS for technical or anatomical reasons, ASL-MRI may have additional diagnostic value. (orig.)

  16. Color-coded perfused blood volume imaging using multidetector CT: initial results of whole-brain perfusion analysis in acute cerebral ischemia

    Energy Technology Data Exchange (ETDEWEB)

    Kloska, Stephan P.; Fischer, Tobias; Fischbach, Roman; Heindel, Walter [University of Muenster, Department of Clinical Radiology, Muenster (Germany); Nabavi, Darius G.; Dittrich, Ralf; Ringelstein, E.B. [University of Muenster, Department of Neurology, Muenster (Germany); Ditt, Hendrik; Klotz, Ernst [Siemens AG, Medical Solutions, Forchheim (Germany)

    2007-09-15

    Computed tomography (CT) is still the primary imaging modality following acute stroke. To evaluate a prototype of software for the calculation of color-coded whole-brain perfused blood volume (PBV) images from CT angiography (CTA) and nonenhanced CT (NECT) scans, we studied 14 patients with suspected acute ischemia of the anterior cerebral circulation. PBV calculations were performed retrospectively. The detection rate of ischemic changes in the PBV images was compared with NECT. The volume of ischemic changes in PBV was correlated with the infarct volume on follow-up examination taking potential vessel recanalization into account. PBV demonstrated ischemic changes in 12/12 patients with proven infarction and was superior to NECT (8/12) in the detection of early ischemia. Moreover, PBV demonstrated the best correlation coefficient with the follow-up infarct volume (Pearson's R = 0.957; P = 0.003) for patients with proven recanalization of initially occluded cerebral arteries. In summary, PBV appears to be more accurate in the detection of early infarction compared to NECT and mainly visualizes the irreversibly damaged ischemic tissue. (orig.)

  17. In Vivo, Non-Invasive Characterization of Human Bone by Hybrid Broadband (600-1200 nm) Diffuse Optical and Correlation Spectroscopies

    Science.gov (United States)

    Pagliazzi, Marco; Negredo, Eugènia; Martelli, Fabrizio; Farina, Andrea; Dalla Mora, Alberto; Lindner, Claus; Farzam, Parisa; Pérez-Álvarez, Núria; Puig, Jordi; Taroni, Paola; Pifferi, Antonio; Durduran, Turgut

    2016-01-01

    Non-invasive in vivo diffuse optical characterization of human bone opens a new possibility of diagnosing bone related pathologies. We present an in vivo characterization performed on seventeen healthy subjects at six different superficial bone locations: radius distal, radius proximal, ulna distal, ulna proximal, trochanter and calcaneus. A tailored diffuse optical protocol for high penetration depth combined with the rather superficial nature of considered tissues ensured the effective probing of the bone tissue. Measurements were performed using a broadband system for Time-Resolved Diffuse Optical Spectroscopy (TRS) to assess mean absorption and reduced scattering spectra in the 600–1200 nm range and Diffuse Correlation Spectroscopy (DCS) to monitor microvascular blood flow. Significant variations among tissue constituents were found between different locations; with radius distal rich of collagen, suggesting it as a prominent location for bone related measurements, and calcaneus bone having highest blood flow among the body locations being considered. By using TRS and DCS together, we are able to probe the perfusion and oxygen consumption of the tissue without any contrast agents. Therefore, we predict that these methods will be able to evaluate the impairment of the oxygen metabolism of the bone at the point-of-care. PMID:27997565

  18. Non-invasive prenatal testing for aneuploidy and beyond

    DEFF Research Database (Denmark)

    Dondorp, Wybo; de Wert, Guido; Bombard, Yvonne

    2015-01-01

    This paper contains a joint ESHG/ASHG position document with recommendations regarding responsible innovation in prenatal screening with non-invasive prenatal testing (NIPT). By virtue of its greater accuracy and safety with respect to prenatal screening for common autosomal aneuploidies, NIPT ha...

  19. Eyeblink Conditioning: A Non-Invasive Biomarker for Neurodevelopmental Disorders

    Science.gov (United States)

    Reeb-Sutherland, Bethany C.; Fox, Nathan A.

    2015-01-01

    Eyeblink conditioning (EBC) is a classical conditioning paradigm typically used to study the underlying neural processes of learning and memory. EBC has a well-defined neural circuitry, is non-invasive, and can be employed in human infants shortly after birth making it an ideal tool to use in both developing and special populations. In addition,…

  20. Non-invasive terahertz field imaging inside parallel plate waveguides

    DEFF Research Database (Denmark)

    Iwaszczuk, Krzysztof; Andryieuski, Andrei; Lavrinenko, Andrei

    2011-01-01

    We present a non-invasive broadband air photonic method of imaging of the electric field of THz pulses propagating inside a tapered parallel plate waveguide. The method is based on field-enhanced second harmonic generation of the fundamental laser beam in an external electric field. We apply...

  1. Measuring and modulating the brain with non-invasive stimulation

    NARCIS (Netherlands)

    Munneke, M.A.M

    2014-01-01

    The overall goal of the studies in this thesis was the use of non-invasive brain stimulation for measuring and modulating corticospinal excitability and to study the possibility of therapeutic modulation of excitability in some neurological disorders. Brain modulation to reduce the over-excitability

  2. Non-invasive diagnosis and management of ectopic pregnancy

    NARCIS (Netherlands)

    van Mello, N.M.

    2013-01-01

    The work presented in this thesis begins with a focus on non-invasive diagnostic methods for ectopic pregnancy. The heterogeneity found in studies on diagnostic tests for ectopic pregnancy has led to an international recommendation on uniform definitions of early pregnancy complications. Hereafter,

  3. Non-invasive in vivo measurement of macular carotenoids

    Science.gov (United States)

    Lambert, James L. (Inventor); Borchert, Mark S. (Inventor)

    2009-01-01

    A non-invasive in vivo method for assessing macular carotenoids includes performing Optical Coherence Tomography (OCT) on a retina of a subject. A spatial representation of carotenoid levels in the macula based on data from the OCT of the retina can be generated.

  4. Potential diagnostic consequences of applying non-invasive prenatal testing

    DEFF Research Database (Denmark)

    Petersen, Olav Bjørn; Vogel, I; Ekelund, C

    2014-01-01

    OBJECTIVES: Targeted non-invasive prenatal testing (NIPT) tests for trisomies 21, 18 and 13 and sex chromosome aneuploidies and could be an alternative to traditional karyotyping. The aim of this study was to determine the risk of missing other abnormal karyotypes of probable phenotypic...

  5. New developments in non-invasive coronary imaging

    NARCIS (Netherlands)

    Dikkers, Riksta

    2008-01-01

    Coronary artery disease, and especially ischemic heart disease, is a major concern in Western society. To reduce mortality and morbidity early detection and treatment is important. Ideally, early detection should be non-invasive, fast and cheap. Coronary angiography (CAG) is a reliable technique to

  6. Non-invasive imaging of human embryonic stem cells.

    Science.gov (United States)

    Hong, Hao; Yang, Yunan; Zhang, Yin; Cai, Weibo

    2010-09-01

    Human embryonic stem cells (hESCs) hold tremendous therapeutic potential in a variety of diseases. Over the last decade, non-invasive imaging techniques have proven to be of great value in tracking transplanted hESCs. This review article will briefly summarize the various techniques used for non-invasive imaging of hESCs, which include magnetic resonance imaging (MRI), bioluminescence imaging (BLI), fluorescence, single-photon emission computed tomography (SPECT), positron emission tomography (PET), and multimodality approaches. Although the focus of this review article is primarily on hESCs, the labeling/tracking strategies described here can be readily applied to other (stem) cell types as well. Non-invasive imaging can provide convenient means to monitor hESC survival, proliferation, function, as well as overgrowth (such as teratoma formation), which could not be readily investigated previously. The requirement for hESC tracking techniques depends on the clinical scenario and each imaging technique will have its own niche in preclinical/clinical research. Continued evolvement of non-invasive imaging techniques will undoubtedly contribute to significant advances in understanding stem cell biology and mechanisms of action.

  7. Non-invasive diagnosis and management of ectopic pregnancy

    NARCIS (Netherlands)

    van Mello, N.M.

    2013-01-01

    The work presented in this thesis begins with a focus on non-invasive diagnostic methods for ectopic pregnancy. The heterogeneity found in studies on diagnostic tests for ectopic pregnancy has led to an international recommendation on uniform definitions of early pregnancy complications. Hereafter,

  8. New developments in non-invasive coronary imaging

    NARCIS (Netherlands)

    Dikkers, Riksta

    2008-01-01

    Coronary artery disease, and especially ischemic heart disease, is a major concern in Western society. To reduce mortality and morbidity early detection and treatment is important. Ideally, early detection should be non-invasive, fast and cheap. Coronary angiography (CAG) is a reliable technique to

  9. Measuring and modulating the brain with non-invasive stimulation

    NARCIS (Netherlands)

    Munneke, M.A.M

    2014-01-01

    The overall goal of the studies in this thesis was the use of non-invasive brain stimulation for measuring and modulating corticospinal excitability and to study the possibility of therapeutic modulation of excitability in some neurological disorders. Brain modulation to reduce the over-excitability

  10. Non-invasive assessment of maternal hemodynamics in early pregnancy

    NARCIS (Netherlands)

    van der Graaf, Anne Marijn; Zeeman, Gerda G.; Groen, Henk; Roberts, Claire; Dekker, Gus A.

    2013-01-01

    Objectives: Non-invasive assessment of maternal hemodynamics in early pregnancy may be promising in evaluating maternal hemodynamic (mal)adaptation to pregnancy. We explored usage of applanation tonometry and Doppler ultrasound for assessment of cardiac output (CO), systemic vascular resistance (SVR

  11. Quantitative evaluation of MR perfusion imaging using blood pool contrast agent in subjects without pulmonary diseases and in patients with pulmonary embolism

    Energy Technology Data Exchange (ETDEWEB)

    Hansch, Andreas; Hinneburg, Uta [University Hospital Jena, Institute of Diagnostic and Interventional Radiology II, Jena (Germany); University Hospital Jena, Institute of Diagnostic and Interventional Radiology II, Gera (Germany); Kohlmann, Peter; Laue, Hendrik [Fraunhofer MEVIS - Institute for Medical Image Computing, Bremen (Germany); Boettcher, Joachim [SRH Klinikum Gera, Institute of Diagnostic and Interventional Radiology, Gera (Germany); Malich, Ansgar [Suedharzkrankenhaus Nordhausen, Institute of Diagnostic and Interventional Radiology, Nordhausen (Germany); Wolf, Gunter [University Hospital Jena, Department of Internal Medicine III, Jena (Germany); Pfeil, Alexander [University Hospital Jena, Institute of Diagnostic and Interventional Radiology II, Jena (Germany); University Hospital Jena, Institute of Diagnostic and Interventional Radiology II, Gera (Germany); University Hospital Jena, Department of Internal Medicine III, Jena (Germany)

    2012-08-15

    To assess the feasibility of time-resolved parallel three-dimensional magnetic resonance imaging (MRI) for quantitative analysis of pulmonary perfusion using a blood pool contrast agent. Quantitative perfusion analysis was performed using novel software to assess pulmonary blood flow (PBF), pulmonary blood volume (PBV) and mean transit time (MTT) in a quantitative manner. The evaluation of lung perfusion in the normal subjects showed an increase of PBF, PBV ventrally to dorsally (gravitational direction), and the highest values at the upper lobe, with a decrease to the middle and lower lobe (isogravitational direction). MTT showed no relevant changes in either the gravitational or isogravitational directions. In comparison with normally perfused lung areas (in diseased patients), the pulmonary embolism (PE) regions showed a significantly lower mean PBF (20 {+-} 0.6 ml/100 ml/min, normal region 94 {+-} 1 ml/100 ml/min; P < 0.001), mean PBV (2 {+-} 0.1 ml/100 ml, normal region 9.8 {+-} 0.1 ml/100 ml; P < 0.001) and mean MTT (3.8 {+-} 0.1 s; normal region 6.3 {+-} 0.1; P < 0.001). Our results demonstrate the feasibility of using time-resolved dynamic contrast-enhanced MRI to determine normal range and regional variation of pulmonary perfusion and perfusion deficits in patients with PE. (orig.)

  12. [Blood perfusion in different facial acupoint areas and its changes after acupuncture stimulation of Hegu (LI 4) displayed by laser Doppler imager in healthy volunteers].

    Science.gov (United States)

    Wang, Shu-You; Qu, Xiao-Xiao; Song, Xiao-Jing; Li, Shun-Yue; Ma, Hui-Min; Zhang, Dong

    2012-12-01

    To observe the blood perfusion levels in different facial acupoint regions and changes after acupuncture stimulation of Hegu (LI 4). Thirty healthy volunteer subjects were equally divided into control group and acupuncture group. Blood perfusion levels of different facial acupoint areas were detected using a Laser Doppler Imager. Acupuncture stimulation was applied to bilateral Hegu (LI 4) by using two filiform needles which were manipulated for a while till "Deqi", followed by keeping them in position for 30 min. The needles were then manipulated once again every 10 min. The blood perfusion levels of facial acupoint regions were from 0.73 to 1.17 PU in healthy volunteers, with relatively higher levels being in Juliao (ST 3), Kouheliao (LI 19), Sibai (ST 2) and Chengqi (ST 1) regions and relatively lower levels in Xiaguan (ST 7), Qianzheng (Ex-HN) and Sizhukong (TE 23) regions, but without significant difference between the isonym acupoint areas of the bilateral face in the control group. Following acupuncture stimulation of bilateral Hegu (LI 4), the blood perfusion volumes were remarkably increased in the acupoint regions on bilateral sides of the face (P < 0.05, P < 0.01). Acupuncture of Hegu (LI 4) can effectively increase blood perfusion volume of the acupoint areas of the bilateral face in healthy volunteers.

  13. Perfusion magnetic resonance imaging with continuous arterial spin labeling: methods and clinical applications in the central nervous system

    Energy Technology Data Exchange (ETDEWEB)

    Detre, John A. E-mail: detre@mail.med.upenn.edu; Alsop, David C

    1999-05-01

    Several methods are now available for measuring cerebral perfusion and related hemodynamic parameters using magnetic resonance imaging (MRI). One class of techniques utilizes electromagnetically labeled arterial blood water as a noninvasive diffusible tracer for blood flow measurements. The electromagnetically labeled tracer has a decay rate of T1, which is sufficiently long to allow perfusion of the tissue and microvasculature to be detected. Alternatively, electromagnetic arterial spin labeling (ASL) may be used to obtain qualitative perfusion contrast for detecting changes in blood flow, similar to the use of susceptibility contrast in blood oxygenation level dependent functional MRI (BOLD fMRI) to detect functional activation in the brain. The ability to obtain blood flow maps using a non-invasive and widely available modality such as MRI should greatly enhance the utility of blood flow measurement as a means of gaining further insight into the broad range of hemodynamically related physiology and pathophysiology. This article describes the biophysical considerations pertaining to the generation of quantitative blood flow maps using a particular form of ASL in which arterial blood water is continuously labeled, termed continuous arterial spin labeling (CASL). Technical advances permit multislice perfusion imaging using CASL with reduced sensitivity to motion and transit time effects. Interpretable cerebral perfusion images can now be reliably obtained in a variety of clinical settings including acute stroke, chronic cerebrovascular disease, degenerative diseases and epilepsy. Over the past several years, the technical and theoretical foundations of CASL perfusion MRI techniques have evolved from feasibility studies into practical usage. Currently existing methodologies are sufficient to make reliable and clinically relevant observations which complement structural assessment using MRI. Future technical improvements should further reduce the acquisition times

  14. Measurement of myocardial perfusion using magnetic resonance

    DEFF Research Database (Denmark)

    Fritz-Hansen, T.; Jensen, L.T.; Larsson, H.B.

    2008-01-01

    Cardiac magnetic resonance imaging (MRI) has evolved rapidly. Recent developments have made non-invasive quantitative myocardial perfusion measurements possible. MRI is particularly attractive due to its high spatial resolution and because it does not involve ionising radiation. This paper reviews...... myocardial perfusion imaging with MR contrast agents: methods, validation and experiences from clinical studies. Unresolved issues still restrict the use of these techniques to research although clinical applications are within reach Udgivelsesdato: 2008/12/8...

  15. ORIGINAL ARTICLES Effect of Acupuncture Signal after Brachial Plexus Blockade on Cerebral Blood Perfusion and Brain Cell Function

    Institute of Scientific and Technical Information of China (English)

    RENYong-gong; JIAShao-wei

    2003-01-01

    Objective:Using single photon emission computed tomography (SPECT)to observe the influence of the up-transmitting of acupuncture signal into the brain in health volunteers whose nerve trunk was blocked by anesthetics.Methods:Thirty-one healthy volunteers were divided into two groups,the control group of 20 cases,and the brachial plexus blockade(BPB)group of 11cases,with supraclavicular BPB route adopted.With the control group 2 acupoints were randomly selected(Hegu and Quchi of both sides),while with the BPB group Hegu and Quchi of anesthetic arm side were selected.Siemens ECAM/ICON SPECT system was used to conduct brain imaging using double imaging assay before acupuncture and 99m Tc-ECD imaging agent during acupuncture for cerebral perfusion.The data were quantitatively ana-lyzed by blood functional changing rate (BFCR%) mathematics model.Results:Before acupuncture,the control and BPB groups showed insignificant change by SPECT, but after electro-acupuncture(EA),the control group displayed improved motor and sensory cortex excitability in basal nuclei,contra-lateral thal-amus,parietal and frontal lobe; while BPB group was characterized with reduction of the blood perfusion and cell function of contra-lateral thalamus of anesthetized arm.The difference between the two groups was significant(P<0.01).Conclusion:(1)After BPB,the up-transmitting of the acupuncture signal viaupper limb into the brain,and its strength was impaired or blocked; (2)After BPB, the effect of acupunc-ture on cerebral perfusion and brain cell function of contra-lateral thalamus was impaired or blocked.

  16. 应用新型抗胎儿血红蛋白抗体富集母体循环中胎儿有核红细胞%Enrichment of circulating fetal nucleated red blood cell for non-invasive prenatal diagnosis with a new polyclonal antibody specific to fetal hemoglobin

    Institute of Scientific and Technical Information of China (English)

    汤冬玲; 周新; 李艳; 郑芳; 李从荣; 荣媛

    2008-01-01

    目的 利用多肽合成技术制备抗胎儿血红蛋白(fetal hem-oglobin,HBF)γ链的抗体,探讨其用于检测孕妇外周血中胎儿有核红细胞(nucleated red blood cell,NRBC)进行无创性产前基因诊断的可行性.方法 针对胎儿血红蛋白的特异性抗原表位,选定第69~78位HbF-γ特异的11个氨基酸残基的肽段为免疫原,将人工合成的胎儿血红蛋白γ链的多肽与载体蛋白(KLH)偶联,佐剂乳化后免疫羊,制备羊抗人胎儿血红蛋白的抗血清,经蛋白G纯化,HbF特异性抗体标记、识别、显微操作法富集32例孕周为22~39周的孕妇外周血中的胎儿有核红细胞,引物延伸预扩增后,利用9个短串联重复序列(short tandem repeat,STR)的复合扩增方法对富集的阳性细胞进行扩增,用于孕妇外周血中富集的HbF阳性细胞胎儿来源的遗传学鉴定.结果 经HbF多克隆抗体标记,32名孕妇外周血中均发现与HbF呈阳性反应的胎儿NRBC,并具有鲜明的形态学特征,光学显微镜下可见NRBC细胞质呈棕黄色,核浆比例较低,苏木素复染后胞核呈蓝色,明显区别于其他细胞,每份样本出现NRBC 0.6~1.8个/ml,共计183个,平均为1.3个/ml,经STR多态性基因位点鉴定,准确率为90.6%.结论 利用多肽合成技术制备的抗胎儿血红蛋白γ链的抗体能有效识别母血中的胎儿有核红细胞,可应用于无创性产前基因诊断,具备良好的应用前景.%Objective To investigate the feasibility of a new polyclonal antibody specific to fetal hemoglobin (HbF) and its application in enrichment of circulating fetal nucleated red blood cell(NRBC) for non-invasive prenatal diagnosis. Methods A polyclonal antibody against a synthetic peptide comprising residues 69-78 of the γ-chain of HbF was prepared and conjugated to carrier protein KLH as the immunogen according to the specific antigenic determinant. The peptide-KLH solution was mixed with freund's complete or incomplete adjuvant and

  17. Investigation of hepatic blood perfusion by laser speckle imaging and changes of hepatic vasoactive substances in mice after electroacupuncture.

    Science.gov (United States)

    Song, Xiao-Jing; Zhang, Dong; Wang, Shu-You; Li, Shun-Yue

    2014-01-01

    The study was conducted to observe the effect of electroacupuncture (EA) on hepatic blood perfusion (HBP) and vascular regulation. We investigated 60 male anesthetized mice under the following 3 conditions: without EA stimulation (control group); EA stimulation at Zusanli (ST36 group); EA stimulation at nonacupoint (NA group) during 30 min. The HBP was measured using the laser speckle perfusion imaging (LSPI). The level of nitric oxide (NO), endothelin-1 (ET-1), and noradrenaline (NE) in liver tissue was detected by biochemical methods. Results were as follows. At each time point, HBP increase in ST36 group was higher than that in the NA group in anesthetized mice. HBP gradually decreased during 30 min in control group. The level of NO in ST36 group was higher than that in NA group. The level of both ET-1 and NE was the highest in control group, followed by NA group and ST36 group. It is concluded that EA at ST36 could increase HBP possibly by increasing the blood flow velocity (BFV), changing vascular activity, increasing the level of NO, and inhibiting the level of ET-1 in liver tissue.

  18. Investigation of Hepatic Blood Perfusion by Laser Speckle Imaging and Changes of Hepatic Vasoactive Substances in Mice after Electroacupuncture

    Directory of Open Access Journals (Sweden)

    Xiao-jing Song

    2014-01-01

    Full Text Available The study was conducted to observe the effect of electroacupuncture (EA on hepatic blood perfusion (HBP and vascular regulation. We investigated 60 male anesthetized mice under the following 3 conditions: without EA stimulation (control group; EA stimulation at Zusanli (ST36 group; EA stimulation at nonacupoint (NA group during 30 min. The HBP was measured using the laser speckle perfusion imaging (LSPI. The level of nitric oxide (NO, endothelin-1 (ET-1, and noradrenaline (NE in liver tissue was detected by biochemical methods. Results were as follows. At each time point, HBP increase in ST36 group was higher than that in the NA group in anesthetized mice. HBP gradually decreased during 30 min in control group. The level of NO in ST36 group was higher than that in NA group. The level of both ET-1 and NE was the highest in control group, followed by NA group and ST36 group. It is concluded that EA at ST36 could increase HBP possibly by increasing the blood flow velocity (BFV, changing vascular activity, increasing the level of NO, and inhibiting the level of ET-1 in liver tissue.

  19. Comparison of Acupuncture Effect on Blood Perfusion between Needling Nonacupoint on Meridian and Needling Nonacupoint off Meridian

    Directory of Open Access Journals (Sweden)

    Wei-Bo Zhang

    2013-01-01

    Full Text Available To verify the ancient theory of rather missing the acupoint than missing the meridian, acupuncture at nonacupoint on meridian and acupuncture at nonacupoint off meridian were performed, respectively. The blood perfusion (BP on the calf around bladder meridian area was measured with a laser Doppler perfusion imager before, during, and after acupuncture. The whole scanning field was divided into seven subareas, and mean BP on each area was calculated. The ratio of mean BP between a subarea and a reference subarea was gotten, and then the change rate was calculated as ratio change rate (RCR. The results showed that RCR on bladder meridian area and around Chengshan (BL57 during or after acupuncture at nonacupoint on meridian was significantly higher than that at nonacupoint off meridian, which supports the ancient theory. Such differences may be attributable to some factors that can facilitate the signals transmission and produce a better acupuncture effect, such as richer nerve terminals, blood vessels, and mast cells which can produce stronger signals on the acupoints and the low hydraulic resistance channel along meridians which plays a role of signal transmitting channel to get a better effect of acupuncture.

  20. Value or waste: Perfusion imaging following radiofrequency ablation - early experience.

    Science.gov (United States)

    Thieme, Stefan F; Vahldiek, Janis L; Tummler, Katja; Poch, Franz; Gemeinhardt, Ole; Hiebl, Bernhard; Lehmann, Kai S; Hamm, B; Niehues, Stefan M

    2015-01-01

    Radiofrequency ablation (RFA) is an evolving technique in treatment of hepatic malignant tumors. By heating local tissue it leads to coagulative necrotic areas around the ablation probe. Temperature falls with increasing distance to the probe, risking incomplete necrosis at the margins of the RFA-induced lesion. Therefore, immediate non-invasive and precise detection of incomplete ablation is necessary for early enlargement of the ablation if needed. This in vivo pig study compares early experiences of immediate post-interventional computed tomography (CT) perfusion volume analysis to macroscopic and CT image evaluation in healthy pig liver. RFA was performed in vivo in healthy pig livers. Different CT perfusion algorithms (Maximum slope analysis and Patlak plot) were used to quantify three different perfusion parameters. Data points were acquired from rectangular grids. These grids were semiautomatically overlayed to macroscopic images documented after liver explantation. Each data point was visually assigned to zones defined as "inner" and "outer necrotic zone", "margin" or "vital tissue". Significant differences between necrotic zones and vital tissue are shown for equivalent blood volume (p <  0.0001), arterial flow (p <  0.01) and flow extraction product (p <  0.001). Looking at equivalent blood volume and flow extraction product, there were also significant differences (EquivBV: p <  0.0001, FE: p <  0.001) between margins, necrotic and vital areas. In a porcine model these early results could show that all of the used CT perfusion parameters allowed discrimination of necrosis from vital tissue after RFA at high levels of significance. In addition, the parameters EquivBV and FE that give an estimate of the tissue blood volume and the permeability, were able to precisely discern different zones also seen macroscopically. From this data CT perfusion analysis could be precise tool for measurement and visualization of ablated liver lesions and

  1. Failure of P-selectin blockade alone to protect the liver from ischemia-reperfusion injury in the isolated blood-perfused rat liver

    Institute of Scientific and Technical Information of China (English)

    Samuel Wyllie; Neal R Barshes; Feng-Qin Gao; Saul J Karpen; John A Goss

    2008-01-01

    AIM: To determine if blockade of P-selectin in the isolated blood-perfused cold ex vivo rat liver model protects the liver from ischemia-reperfusion injury. METHODS: The effect of P-selectin blockade was assessed by employing an isolated blood-perfused cold ex vivo rat liver with or without P-selectin antibody treatment before and after 6 h of cold storage in University of Wisconsin solution.RESULTS: In our isolated blood-perfused rat liver model, pre-treatment with P-selectin antibody failed to protect the liver from ischemia-reperfusion injury, as judged by the elevated aspartate aminotransferase activity. In addition, P-selectin antibody treatment did not significantly reduced hepatic polymorphonuclear leukocyte accumulation after 120 min of perfusion. Histological evaluation of liver sections obtained at 120 min of perfusion showed significant oncotic necrosis in liver sections of both ischemic control and P-selectin antibody-treated groups. However, total bile production after 120 min of perfusion was significantly greater in P-selectin antibody-treated livers, compared to control livers. No significant difference in P-selectin and ICAM-1 mRNAs and proteins, GSH, GSSG, and nuclear NF-κB was found between control and P-selectin antibody-treated livers.CONCLUSION: In conclusion, we have shown that blockade of P-selectin alone failed to reduced polymorphonuclear leukocyte accumulation in the liver and protect hepatocytes from ischemia-reperfusion injury in the isolated blood-perfused cold-ex vivo rat liver model.

  2. Distribution of lung blood on modified bilateral Glenn shunt evaluated by Tc-99m-MAA lung perfusion scintigraphy: A retrospective study.

    Science.gov (United States)

    Si, Biao; Luan, Zhao-Sheng; Wang, Tong-Jian; Ning, Yan-Song; Li, Na; Zhu, Meng; Liu, Zhong-Min; Ding, Guang-Hong; Qiao, Bin

    2016-09-01

    The aim of the present study was to determine the distribution of lung blood in a modified bilateral Glenn procedure designed in our institute with lung perfusion scintigraphy. Sixteen consecutive patients who underwent modified bilateral Glenn operation from 2011 to 2014 were enrolled in the study. The control group consisted of 7 patients who underwent bidirectional Glenn shunt. Radionuclide lung perfusion scintigraphy was performed using Tc-99m-macro aggregated albumin (MAA) in all patients. For the patients in modified bilateral Glenn group, the time at which the radioactivity accumulation peaked did not differ significantly between the right and left lung field (t = 0.608, P = 0.554). The incidence of perfusion abnormality in each lung lobe also did not differ significantly (P = 0.426 by Fisher exact test). The radioactive counts were higher in the right lung than in the left lung, but the difference was not statistically significant (t = 1.502, P = 0.157). Radioactive perfusion in the lower lung field was significantly greater than that in the upper field (t = 4.368, P lung to that in left lung was significantly lower in the modified bilateral Glenn group (t = 3.686, P = 0.002). Lung perfusion scintigraphy confirmed the benefit of the modified bilateral Glenn shunt with regard to more balanced blood perfusion in both lungs.

  3. Blood Pressure is Associated With Cerebral Blood Flow Alterations in Patients With T2DM as Revealed by Perfusion Functional MRI.

    Science.gov (United States)

    Xia, Wenqing; Rao, Hengyi; Spaeth, Andrea M; Huang, Rong; Tian, Sai; Cai, Rongrong; Sun, Jie; Wang, Shaohua

    2015-12-01

    Type 2 diabetes mellitus (T2DM) and hypertension are both associated with cognitive impairment and brain function abnormalities. We investigated whether abnormal cerebral blood flow (CBF) patterns exists in T2DM patients and possible relationships between aberrant CBF and cognitive performance. Furthermore, we examined the influence of hypertension on CBF alterations in T2DM patients. T2DM patients (n = 38) and non-T2DM subjects (n = 40) were recruited from clinics, hospitals, and normal community health screenings. Cerebral blood flow images were collected and analyzed using arterial spin labeling perfusion functional magnetic resonance imaging (fMRI). Regions with major CBF differences between T2DM patients and non-T2DM controls were detected via 1-way ANOVA. The interaction effects between hypertension and T2DM for CBF alterations were also examined. Correlation analyses illustrated the association between CBF values and cognitive performance and between CBF and blood pressure. Compared with non-T2DM controls, T2DM patients exhibited decreased CBF, primarily in the visual area and the default mode network (DMN); decreased CBF in these regions was correlated with cognitive performance. There was a significant interaction effect between hypertension and diabetes for CBF in the precuneus and the middle occipital gyrus. Additionally, blood pressure correlated negatively with CBF in T2DM patients.T2DM patients exhibited reduced CBF in the visual area and DMN. Hypertension may facilitate a CBF decrease in the setting of diabetes. T2DM patients may benefit from blood pressure control to maintain their brain perfusion through CBF preservation.

  4. Non-invasive continuous arterial pressure monitoring with Nexfin does not sufficiently replace invasive measurements in critically ill patients.

    Science.gov (United States)

    Hohn, A; Defosse, J M; Becker, S; Steffen, C; Wappler, F; Sakka, S G

    2013-08-01

    In this study, we tested the reliability of a non-invasive finger-cuff-based continuous arterial blood pressure monitoring device (Nexfin, BMEYE, Amsterdam, NL) in critically ill surgical patients. Invasive intra-arterial and non-invasive arterial pressure measurements from 25 patients during a 4-h period were compared at five time points. Correlation and linear regression analysis were used and mean bias, precision [sd of bias] and limits of agreement (LOA) [bias (2.0 sd)] were calculated using the Bland-Altman method. Eight data pairs were excluded because of error message from the non-invasive technique, and thus a total of 117 data pairs were analysed. Overall, correlation between mean arterial pressure (MAP) was r(2)=0.50. Bias, precision, and LOA between invasive and non-invasive MAP were 6 (12) and -18 to +30 mm Hg. In patients requiring norepinephrine (83 data pairs), correlation was r(2)=0.28 and bias, precision, and LOA were 6 (13) and -20 to +32 mm Hg, whereas in patients not receiving norepinephrine (34 data pairs) r(2) was 0.80 and mean bias, precision, and LOA were 6 (11) and -16 to +28 mm Hg. In patients with peripheral oedema (49 data pairs), r(2) was 0.40 and mean bias, precision and LOA were 7 (15) and -23 to +37 mm Hg. In patients without oedema (64 data pairs), r(2) was 0.66 and mean bias, precision, and LOA were 5 (9) and -13 to +23 mm Hg. Non-invasive blood pressure monitoring with Nexfin does not seem to be sufficiently accurate to replace intra-arterial invasive blood pressure measurements in critically ill patients.

  5. Double-echo perfusion-weighted MR imaging: basic concepts and application in brain tumors for the assessment of tumor blood volume and vascular permeability

    Energy Technology Data Exchange (ETDEWEB)

    Uematsu, Hidemasa [University of Fukui, Department of Radiology, Faculty of Medical Sciences, Fukui (Japan); Maeda, Masayuki [Mie University School of Medicine, Department of Radiology, Mie (Japan)

    2006-01-01

    Perfusion-weighted magnetic resonance (MR) imaging using contrast agents plays a key role in characterizing tumors of the brain. We have shown that double-echo perfusion-weighted MR imaging (DEPWI) is potentially useful in assessing brain tumors. Quantitative indices, such as tumor blood volume, are obtained using DEPWI, which allows correction of underestimation of tumor blood volume due to leakage of contrast agents from tumor vessels, in addition to simultaneous acquisition of tumor vessel permeability. This article describes basic concepts of DEPWI and demonstrates clinical applications in brain tumors. (orig.)

  6. Non-invasive assessment of static scatterer concentration in phantom body fluids using laser speckle contrast analysis technique

    Science.gov (United States)

    Jayanthy, A. K.; Sujatha, N.; Ramasubba Reddy, M.

    2011-04-01

    An adequate amount of supply of blood to the body organs is essential for the optimum survival and function of the cells. The Red Blood Cells (RBC) which are the most abundant cells of the blood transports hemoglobin which in turn carries oxygen from the lungs to the tissues. And hence its concentration in blood is an important factor. In this paper, we are presenting LAser Speckle Contrast Analysis (LASCA) as a tool for analyzing RBC concentration. Preliminary results obtained using body fluid such as blood mimicking phantoms are presented here. The technique described provides a non-contact, non-scanning and whole field method for assessing RBC concentration non-invasively.

  7. MR mapping of temperature and perfusion for hyperthermia therapy

    Science.gov (United States)

    Wlodarczyk, Waldemar; Vlad, Julia; Lange, Thomas; Wust, Peter; Felix, Roland

    2001-05-01

    The promising results, recently obtained in phantom experiments employing the MR-based proton resonance frequency (PRF) method as a non-invasive tool for the temperature monitoring of hyperthermia therapy, are not easily reproduced in vivo. One of the reasons is the impact of perfusion changes on the PRF-measured temperature. In our experiments in vivo, heat was supplied on one side of the volunteers knee or pelvis by a rubber hose with circulating warm water (50iC). The PRF method was calibrated by the constant temperature sensitivity of pure water of 0.011 ppm/iC. MR mapping of perfusion changes was based on T2*-weighted tracking of the first-pass kinetics of contrast agent. The hemodynamic parameters of regional blood volume (rBV) and mean transit time (MTT) were extracted by fitting pixel-by-pixel the first- pass kinetics to the gamma-variate model. Special attention was directed to improve a quality of the automatic non-linear fit at low signal-to-noise values. The distributions of PRF- based temperature changes show large areas of apparently high temperature elevations (exceeding 10iC) in regions close to the heat source, and others with just as large temperature decays in more distant regions. Areas of apparently high temperature elevations correlate with areas of blood flow increase and vice versa. In conclusion, the visible heat- induced PRF changes in vivo are primarily perfusion changes, which mask the much smaller true temperature changes.

  8. Trends in Nanomaterial-Based Non-Invasive Diabetes Sensing Technologies.

    Science.gov (United States)

    Makaram, Prashanth; Owens, Dawn; Aceros, Juan

    2014-04-21

    Blood glucose monitoring is considered the gold standard for diabetes diagnostics and self-monitoring. However, the underlying process is invasive and highly uncomfortable for patients. Furthermore, the process must be completed several times a day to successfully manage the disease, which greatly contributes to the massive need for non-invasive monitoring options. Human serums, such as saliva, sweat, breath, urine and tears, contain traces of glucose and are easily accessible. Therefore, they allow minimal to non-invasive glucose monitoring, making them attractive alternatives to blood measurements. Numerous developments regarding noninvasive glucose detection techniques have taken place over the years, but recently, they have gained recognition as viable alternatives, due to the advent of nanotechnology-based sensors. Such sensors are optimal for testing the amount of glucose in serums other than blood thanks to their enhanced sensitivity and selectivity ranges, in addition to their size and compatibility with electronic circuitry. These nanotechnology approaches are rapidly evolving, and new techniques are constantly emerging. Hence, this manuscript aims to review current and future nanomaterial-based technologies utilizing saliva, sweat, breath and tears as a diagnostic medium for diabetes monitoring.

  9. Targets and probes for non-invasive imaging of β-cells

    Energy Technology Data Exchange (ETDEWEB)

    Jodal, Andreas; Behe, Martin [Paul Scherrer Institut, Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Villigen (Switzerland); Schibli, Roger [Paul Scherrer Institut, Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Villigen (Switzerland); ETH Zurich, Department of Chemistry and Applied Biosciences, Zurich (Switzerland)

    2017-04-15

    β-cells, located in the islets of the pancreas, are responsible for production and secretion of insulin and play a crucial role in blood sugar regulation. Pathologic β-cells often cause serious medical conditions affecting blood glucose level, which severely impact life quality and are life-threatening if untreated. With 347 million patients, diabetes is one of the most prevalent diseases, and will continue to be one of the largest socioeconomic challenges in the future. The diagnosis still relies mainly on indirect methods like blood sugar measurements. A non-invasive diagnostic imaging modality would allow direct evaluation of β-cell mass and would be a huge step towards personalized medicine. Hyperinsulinism is another serious condition caused by β-cells that excessively secrete insulin, like for instance β-cell hyperplasia and insulinomas. Treatment options with drugs are normally not curative, whereas curative procedures usually consist of the resection of affected regions for which, however, an exact localization of the foci is necessary. In this review, we describe potential tracers under development for targeting β-cells with focus on radiotracers for PET and SPECT imaging, which allow the non-invasive visualization of β-cells. We discuss either the advantages or limitations for the various tracers and modalities. This article concludes with an outlook on future developments and discuss the potential of new imaging probes including dual probes that utilize functionalities for both a radioactive and optical moiety as well as for theranostic applications. (orig.)

  10. Trends in Nanomaterial-Based Non-Invasive Diabetes Sensing Technologies

    Directory of Open Access Journals (Sweden)

    Prashanth Makaram

    2014-04-01

    Full Text Available Blood glucose monitoring is considered the gold standard for diabetes diagnostics and self-monitoring. However, the underlying process is invasive and highly uncomfortable for patients. Furthermore, the process must be completed several times a day to successfully manage the disease, which greatly contributes to the massive need for non-invasive monitoring options. Human serums, such as saliva, sweat, breath, urine and tears, contain traces of glucose and are easily accessible. Therefore, they allow minimal to non-invasive glucose monitoring, making them attractive alternatives to blood measurements. Numerous developments regarding noninvasive glucose detection techniques have taken place over the years, but recently, they have gained recognition as viable alternatives, due to the advent of nanotechnology-based sensors. Such sensors are optimal for testing the amount of glucose in serums other than blood thanks to their enhanced sensitivity and selectivity ranges, in addition to their size and compatibility with electronic circuitry. These nanotechnology approaches are rapidly evolving, and new techniques are constantly emerging. Hence, this manuscript aims to review current and future nanomaterial-based technologies utilizing saliva, sweat, breath and tears as a diagnostic medium for diabetes monitoring.

  11. Skin Rejuvenation with Non-Invasive Pulsed Electric Fields

    Science.gov (United States)

    Golberg, Alexander; Khan, Saiqa; Belov, Vasily; Quinn, Kyle P.; Albadawi, Hassan; Felix Broelsch, G.; Watkins, Michael T.; Georgakoudi, Irene; Papisov, Mikhail; Mihm, Martin C., Jr.; Austen, William G., Jr.; Yarmush, Martin L.

    2015-05-01

    Degenerative skin diseases affect one third of individuals over the age of sixty. Current therapies use various physical and chemical methods to rejuvenate skin; but since the therapies affect many tissue components including cells and extracellular matrix, they may also induce significant side effects, such as scarring. Here we report on a new, non-invasive, non-thermal technique to rejuvenate skin with pulsed electric fields. The fields destroy cells while simultaneously completely preserving the extracellular matrix architecture and releasing multiple growth factors locally that induce new cells and tissue growth. We have identified the specific pulsed electric field parameters in rats that lead to prominent proliferation of the epidermis, formation of microvasculature, and secretion of new collagen at treated areas without scarring. Our results suggest that pulsed electric fields can improve skin function and thus can potentially serve as a novel non-invasive skin therapy for multiple degenerative skin diseases.

  12. INFLUENCE OF LOCAL INFILITRATION ANESTHESIA OF SCALP-POINT ON ACUPUNCTURE INDUCED CHANGES OF CEREBRAL BLOOD PERFUSION DETECTED BY SPECT

    Institute of Scientific and Technical Information of China (English)

    郭长春; 王凡; 贾少微

    2003-01-01

    Objective: To observe the influence of local infiltration anesthesia at the scalp-point on acupuncture stimulation induced changes of cerebral blood perfusion in the brain. Methods: Experiments were conducted in 10 healthy volunteer subjects (8 males and 2 females) who were ordered to take a lying position on a specific bed with their heads keeping in a fixed position. Scalp-point used was Motor Area (MS 6). The first syringe needle (gauge-5) was inserted into the scalp from the upper 1/5 of MS-6 and the second syringe needle inserted into the scalp from the middle 2/5 of MS-6 and advanced downward, with the two needles connected to a HAN's Therapeutic Apparatus. Images of the brain were then taken before and after electroacupuncture (EA) stimulation, and after local injection of 1% lidocaine [mixed with epinephrine (1∶200,000, 3 mL)] plus EA by using Siemens ECAM/ICON Single Photo Emission Computed Tomography (SPECT). Intravenous injection of Ethyl cysteinate dimmer 555 MBq was performed before displaying cerebral images. Data of blood functional changing rat (BFCR%) were analyzed quantitatively using a mathematic model. Results: Before EA stimulation, the blood perfusion and function of cerebral cortex, thalamus, basal ganglion and cerebellum on both sides of the brain were basically symmetry. Following EA of MS-6, BFCR% of the contralateral thalamus, parietal lobe and the frontal lobe increased significantly. Following local infiltration anesthesia, BFCR% of the contralatral thalamus declined markedly (P<0.05). The results of quantitative analysis were in agreement with those of visual observation. Conclusion: Local infiltration anesthesia of the scalp-point can significantly weaken or block EA stimulation induced changes of BFCR%.

  13. Effect of combined VEGF165/ SDF-1 gene therapy on vascular remodeling and blood perfusion in cerebral ischemia.

    Science.gov (United States)

    Hu, Guo-Jie; Feng, Yu-Gong; Lu, Wen-Peng; Li, Huan-Ting; Xie, Hong-Wei; Li, Shi-Fang

    2016-12-16

    OBJECTIVE Therapeutic neovascularization is a promising strategy for treating patients after an ischemic stroke; however, single-factor therapy has limitations. Stromal cell-derived factor 1 (SDF-1) and vascular endothelial growth factor (VEGF) proteins synergistically promote angiogenesis. In this study, the authors assessed the effect of combined gene therapy with VEGF165 and SDF-1 in a rat model of cerebral infarction. METHODS An adenoviral vector expressing VEGF165 and SDF-1 connected via an internal ribosome entry site was constructed (Ad- VEGF165-SDF-1). A rat model of middle cerebral artery occlusion (MCAO) was established; either Ad- VEGF165-SDF-1 or control adenovirus Ad- LacZ was stereotactically microinjected into the lateral ventricle of 80 rats 24 hours after MCAO. Coexpression and distribution of VEGF165 and SDF-1 were examined by reverse-transcription polymerase chain reaction, Western blotting, and immunofluorescence. The neurological severity score of each rat was measured on Days 3, 7, 14, 21, and 28 after MCAO. Angiogenesis and vascular remodeling were evaluated via bromodeoxyuridine and CD34 immunofluorescence labeling. Relative cerebral infarction volumes were determined by T2-weighted MRI and triphenyltetrazolium chloride staining. Cerebral blood flow, relative cerebral blood volume, and relative mean transmit time were assessed using perfusion-weighted MRI. RESULTS The Ad- VEGF165-SDF-1 vector mediated coexpression of VEGF165 and SDF-1 in multiple sites around the ischemic core, including the cortex, corpus striatum, and hippocampal granular layer. Coexpression of VEGF165 and SDF-1 improved neural function, reduced cerebral infarction volume, increased microvascular density and promoted angiogenesis in the ischemic penumbra, and improved cerebral blood flow and perfusion. CONCLUSIONS Combined VEGF165 and SDF-1 gene therapy represents a potential strategy for improving vascular remodeling and recovery of neural function after cerebral

  14. Invasive versus non-invasive diagnosis of renal bone disease.

    Science.gov (United States)

    Fournier, A; Oprisiu, R; Said, S; Sechet, A; Ghazali, A; Marié, A; el Esper, I; Brazier, M; Achard, J M; Morinière, P

    1997-07-01

    At present, bone histomorphometry remains the gold standard for the diagnosis of the various types of renal bone disease. In the search for a non-invasive method of diagnosis, biochemical serum markers of bone remodelling, in addition to serum intact parathyroid hormone and aluminium determinations, have been proposed as the most reliable tools and are at present widely used in clinical practice. Their respective diagnostic values, as separate items and in combined analysis, are thoroughly discussed in the present review.

  15. Observation of Microvascular Perfusion in the Hegu (LI4 Acupoint Area after Deqi Acupuncture at Quchi (LI11 Acupoint Using Speckle Laser Blood Flow Scanning Technology

    Directory of Open Access Journals (Sweden)

    Tao Huang

    2012-01-01

    Full Text Available The aim of this study was to investigate the traditional meridian theory using speckle laser blood flow scanning technology to observe microcirculation of the Hegu acupoint area after acupuncture stimulation on distant points. An observational study was conducted to observe the microvascular perfusion of Hegu (LI4 and control points after acupuncturing Quchi (LI11. Thirty healthy volunteers (mean age 31.6±8.7 years received deqi acupuncture on Quchi (LI11, right side, and simultaneously changes in microvascular perfusion of Sanjian (LI3, Hegu (LI4, Yangxi (LI5, and two control points were observed before, during, and after needling using a MOOR speckle laser. The results showed that the changes in microvascular perfusion of the observed points are not regular. After correction, the experiment showed that the blood perfusion on 3 meridian acupoints was increased while the perfusion on 2 control points was decreased following acupuncture stimulation, the changes at Hegu (LI4 being the statistically most significant ones. Deqi acupuncture can help in regulating the body's blood flow, with a certain degree of meridian specificity.

  16. Observation of Microvascular Perfusion in the Hegu (LI4) Acupoint Area after Deqi Acupuncture at Quchi (LI11) Acupoint Using Speckle Laser Blood Flow Scanning Technology.

    Science.gov (United States)

    Huang, Tao; Yang, Li-Jian; Zhang, Wei-Bo; Jia, Shu-Yong; Tian, Yu-Ying; Wang, Guan-Jun; Mu, Xiang; Wang, Lu; Litscher, Gerhard

    2012-01-01

    The aim of this study was to investigate the traditional meridian theory using speckle laser blood flow scanning technology to observe microcirculation of the Hegu acupoint area after acupuncture stimulation on distant points. An observational study was conducted to observe the microvascular perfusion of Hegu (LI4) and control points after acupuncturing Quchi (LI11). Thirty healthy volunteers (mean age 31.6 ± 8.7 years) received deqi acupuncture on Quchi (LI11, right side), and simultaneously changes in microvascular perfusion of Sanjian (LI3), Hegu (LI4), Yangxi (LI5), and two control points were observed before, during, and after needling using a MOOR speckle laser. The results showed that the changes in microvascular perfusion of the observed points are not regular. After correction, the experiment showed that the blood perfusion on 3 meridian acupoints was increased while the perfusion on 2 control points was decreased following acupuncture stimulation, the changes at Hegu (LI4) being the statistically most significant ones. Deqi acupuncture can help in regulating the body's blood flow, with a certain degree of meridian specificity.

  17. Detection of fetal mutations causing hemoglobinopathies by non-invasive prenatal diagnosis from maternal plasma

    Directory of Open Access Journals (Sweden)

    E D′Souza

    2013-01-01

    Full Text Available Background: Prenatal diagnosis of hemoglobinopathies enables couples at risk to have a healthy child. Currently used fetal sampling procedures are invasive with some risk of miscarriage. A non-invasive approach to obtain fetal deoxyribonucleic acid (DNA for diagnosis would eliminate this risk. Aim: To develop and evaluate a non-invasive prenatal diagnostic approach for hemoglobinopathies using cell-free fetal DNA circulating in the maternal plasma. Settings and Design: Couples referred to us for prenatal diagnosis of hemoglobinopathies where the maternal and paternal mutations were different were included in the study. Materials and Methods: Maternal peripheral blood was collected at different periods of gestation before the invasive fetal sampling procedure was done. The blood was centrifuged to isolate the plasma and prepare DNA. A size separation approach was used to isolate fetal DNA. Nested polymerase chain reaction (PCR-based protocols were developed for detection of the presence or absence of the paternal mutation. Results and Conclusions: There were 30 couples where the parental mutations were different. Of these, in 14 cases the paternal mutation was absent and in 16 cases it was present in the fetus. Using cell-free fetal DNA from maternal plasma, the absence of the paternal mutation was accurately determined in 12 of the 14 cases and the presence of the paternal mutation was correctly identified in 12 of the 16 cases. Thus, this non-invasive approach gave comparable results to those obtained by the conventional invasive fetal sampling methods in 24 cases giving an accuracy of 80.0%. Although the nested PCR approach enabled amplification of small quantities of cell-free DNA from maternal plasma at different periods of gestation after size separation to eliminate the more abundant maternal DNA, an accurate diagnosis of the presence or absence of the paternal mutation in the fetus was not possible in all cases to make it clinically

  18. An alternative approach to estimation of the brain perfusion index for measurement of cerebral blood flow using technetium-99m compounds

    Energy Technology Data Exchange (ETDEWEB)

    Murase, Kenya; Mochizuki, Teruhito; Ikezoe, Junpei [Dept. of Radiology, Ehime University School of Medicine, Shitsukawa, Shigenobu-cho (Japan); Inoue, Takeshi; Fujioka, Hiroyoshi; Ishimaru, Yoshihiro; Akamune, Akihisa [Dept. of Radiology, Matsuyama Shimin Hospital, Ohte-machi, Matsuyama, Ehime (Japan); Yamamoto, Yuji [Department of Neurosurgery, Matsuyama Shimin Hospital, Ohte-machi, Matsuyama, Ehime (Japan)

    1999-10-01

    Cerebral blood flow (CBF) has been quantified non-invasively using the brain perfusion index (BPI) determined from radionuclide angiographic data generated by technetium-99m hexamethylpropylene amine oxime ({sup 99m}Tc-HMPAO) or technetium-99m ethyl cysteinate dimer ({sup 99m}Tc-ECD). The BPI is generally calculated using graphical analysis (GA). In the present study, BPI was measured using spectral analysis (SA), and its usefulness evaluated in comparison with GA. The BPI was calculated from the sum of spectral data obtained by SA. We applied this method to radionuclide angiographic data collected from the bilateral brain hemispheres of 20 patients with various brain diseases using {sup 99m}Tc-HMPAO and from those of 20 patients using {sup 99m}Tc-ECD. We also measured BPI using GA. The BPI values obtained by SA (BPI{sup S}) (x) and by GA (BPI{sup G}) (y) correlated closely (y=0.708x+0.038, r=0.945 for {sup 99m}Tc-HMPAO and y=0.559x+0.093, r=0.931 for {sup 99m}Tc-ECD). However, the BPI{sup G} values were underestimated by 22.9%{+-}6.6% (mean{+-}SD) for {sup 99m}Tc-HMPAO and by 27.9%{+-}7.5% for {sup 99m}Tc-ECD as compared with the BPI{sup S} values. The extent of underestimation tended to increase with increasing BPI{sup S} values. These findings were considered to be a result of the BPI{sup G} values being affected by the first-pass extraction fraction of the tracer. We also compared the BPI{sup S} and BPI{sup G} values with those of CBF measured using N-isopropyl-p-[{sup 123}I]iodoamphetamine (CBF{sup IMP}) in 16 patients (six for {sup 99m}Tc-HMPAO and ten for {sup 99m}Tc-ECD). Although both BPI{sup S} and BPI{sup G} values correlated significantly with the CBF{sup IMP} values, the correlation coefficient in BPI{sup S} was always better than that in BPI{sup G} (r=0.869 for {sup 99m}Tc-HMPAO and r=0.929 for {sup 99m}Tc-ECD in BPI{sup S}, r=0.629 for {sup 99m}Tc-HMPAO and r=0.856 for {sup 99m}Tc-ECD in BPI{sup G}). These results suggest that SA can provide a more

  19. Effects of cardioplegia induced by a Young's solution (YNG solution) on the blood-perfused canine papillary muscle preparation.

    Science.gov (United States)

    Satoh, H; Ohkubo, K; Suzuki, K; Katano, Y; Otorii, T; Kawada, T; Yoshida, S; Imai, S

    1984-03-01

    Experiments were carried out in the blood-perfused canine papillary muscle preparation to evaluate the protective effect of a cardioplegic solution, Young's solution (YNG solution), on the myocardial function. Both in spontaneously contracting preparations and in electrically paced (2 Hz) preparations, the time to the cardiac arrest and the time to the maximum blood flow were found to be significantly shorter when the cardiac arrest was induced with cardioplegic solutions than when it was induced with the cold modified Krebs-Ringer's solution (cold cardioplegia). The maximum blood flow of the paced preparation tended to be greater with cardioplegic solutions. The time to resumption of regular contractions was significantly shorter with YNG solution as compared with cold cardioplegia. The developed tension and the blood flow at the time of resumption of the regular contractions tended to approach the control value more quickly with YNG solution, as compared with other cardioplegic solutions and cold cardioplegia. It is concluded that YNG solution represents an optimal cardioplegic solution.

  20. The relationship between exercise-induced muscle fatigue, arterial blood flow and muscle perfusion after 56 days local muscle unloading.

    Science.gov (United States)

    Weber, Tobias; Ducos, Michel; Mulder, Edwin; Beijer, Åsa; Herrera, Frankyn; Zange, Jochen; Degens, Hans; Bloch, Wilhelm; Rittweger, Jörn

    2014-05-01

    In the light of the dynamic nature of habitual plantar flexor activity, we utilized an incremental isokinetic exercise test (IIET) to assess the work-related power deficit (WoRPD) as a measure for exercise-induced muscle fatigue before and after prolonged calf muscle unloading and in relation to arterial blood flow and muscle perfusion. Eleven male subjects (31 ± 6 years) wore the HEPHAISTOS unloading orthosis unilaterally for 56 days. It allows habitual ambulation while greatly reducing plantar flexor activity and torque production. Endpoint measurements encompassed arterial blood flow, measured in the femoral artery using Doppler ultrasound, oxygenation of the soleus muscle assessed by near-infrared spectroscopy, lactate concentrations determined in capillary blood and muscle activity using soleus muscle surface electromyography. Furthermore, soleus muscle biopsies were taken to investigate morphological muscle changes. After the intervention, maximal isokinetic torque was reduced by 23·4 ± 8·2% (PBlood flow, tissue oxygenation, lactate concentrations and EMG median frequency kinematics during the exercise test were comparable before and after the intervention, whereas the increase of RMS in response to IIET was less following the intervention (P = 0·03). In conclusion, following submaximal isokinetic muscle work exercise-induced muscle fatigue is unaffected after prolonged local muscle unloading. The observation that arterial blood flow was maintained may underlie the unchanged fatigability.

  1. Comparison of Cerebral Oxygen Saturation and Cerebral Perfusion Computed Tomography in Cerebral Blood Flow in Patients with Brain Injury.

    Science.gov (United States)

    Trofimov, Alexey O; Kalentiev, George; Voennov, Oleg; Grigoryeva, Vera

    2016-01-01

    The purpose of this study was to determine the relationship between cerebral tissue oxygen saturation and cerebral blood volume in patients with traumatic brain injury. Perfusion computed tomography of the brain was performed in 25 patients with traumatic brain injury together with simultaneous SctO2 level measurement using cerebral near-infrared oxymetry. The mean age of the injured persons was 34.5±15.6 years (range 15-65); 14 men, 11 women. The Injury Severity Score (ISS) values were 44.4±9.7 (range 25-81). The Glasgow Coma Score (GCS) mean value before the study was 10.6±2.1 (range 5-13). SctO2 ranged from 51 to 89%, mean 62±8.2%. Cerebral blood volume (CBV) values were 2.1±0.67 ml/100 g (min 1.1; max 4.3 ml/100 g). Cerebral blood flow (CBF) was 31.99±13.6 ml/100 g×min. Mean transit time (MTT) values were 5.7±4.5 s (min 2.8; max 34.3 s). The time to peak (TTP) was 22.2±3.1 s. A statistically significant correlation was found between SctO2 level and cerebral blood volume (CBV) level (R=0.9; pperfusion.

  2. Comparative imaging of differential pulmonary blood flow in patients with congenital heart disease: magnetic resonance imaging versus lung perfusion scintigraphy.

    Science.gov (United States)

    Roman, Kevin S; Kellenberger, Christian J; Farooq, Saqba; MacGowan, Christopher K; Gilday, David L; Yoo, Shi-Joon

    2005-03-01

    Lung perfusion scintigraphy is considered the gold standard to assess differential pulmonary blood flow while magnetic resonance (MR) has been shown to be an accurate alternative in some studies. The purpose of the study was to assess the accuracy of phase contrast magnetic resonance (PC-MR) in measuring pulmonary blood flow ratio compared with lung perfusion scintigraphy in patients with complex pulmonary artery anatomy or pulmonary hypertension and to document reasons for discrepant results. We identified 25 cases of congenital heart disease between January 2000 and 2003, in whom both techniques of assessing pulmonary blood flow were performed within a 6-month period without an interim surgical or transcatheter intervention. The study group included cases with branch pulmonary artery stenosis, intracardiac shunts, single ventricle circulation, pulmonary venous anomalies and conotruncal defects. The mean age at study was 5.7 years (range 0.33-12) with a mean weight of 20.3 kg (range 6.5-53.6). The two methods were compared using a Bland-Altman analysis, and the Pearson correlation coefficient was calculated using the lung scan as the gold standard. Discrepant results were examined by reviewing the source images to elucidate reasons for error by MR. Bland-Altman analysis comparing right pulmonary artery (RPA) blood flow percentage, as measured by each modality, showed a mean difference of 1.43+/-9.8 (95% limits of agreement: -17.8, 20.6) with a correlation coefficient of r=0.84, P10%) was found with a mean difference between techniques of 17.9%. The reasons for discrepant results included MR artifacts, dephasing owing to turbulent flow, site of data acquisition and lobar lung collapse. When using PC-MR to assess pulmonary blood flow ratio, important technical errors occur in a significant proportion of patients who have abnormal pulmonary artery anatomy or pulmonary hypertension. If these technical errors are avoided, PC-MR is able to supply both anatomic and

  3. Comparative imaging of differential pulmonary blood flow in patients with congenital heart disease: magnetic resonance imaging versus lung perfusion scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Roman, Kevin S. [Hospital for Sick Children, Department of Cardiology, Toronto, ON (Canada); Kellenberger, Christian J.; Farooq, Saqba; MacGowan, Christopher K.; Gilday, David L.; Yoo, Shi-Joon [Hospital for Sick Children, Diagnostic Imaging and Radiology, Toronto, ON (Canada)

    2005-03-01

    Lung perfusion scintigraphy is considered the gold standard to assess differential pulmonary blood flow while magnetic resonance (MR) has been shown to be an accurate alternative in some studies. The purpose of the study was to assess the accuracy of phase contrast magnetic resonance (PC-MR) in measuring pulmonary blood flow ratio compared with lung perfusion scintigraphy in patients with complex pulmonary artery anatomy or pulmonary hypertension and to document reasons for discrepant results. We identified 25 cases of congenital heart disease between January 2000 and 2003, in whom both techniques of assessing pulmonary blood flow were performed within a 6-month period without an interim surgical or transcatheter intervention. The study group included cases with branch pulmonary artery stenosis, intracardiac shunts, single ventricle circulation, pulmonary venous anomalies and conotruncal defects. The mean age at study was 5.7 years (range 0.33-12) with a mean weight of 20.3 kg (range 6.5-53.6). The two methods were compared using a Bland-Altman analysis, and the Pearson correlation coefficient was calculated using the lung scan as the gold standard. Discrepant results were examined by reviewing the source images to elucidate reasons for error by MR. Bland-Altman analysis comparing right pulmonary artery (RPA) blood flow percentage, as measured by each modality, showed a mean difference of 1.43{+-}9.8 (95% limits of agreement: -17.8, 20.6) with a correlation coefficient of r=0.84, P<0.0001. In six (24%) cases a large difference (>10%) was found with a mean difference between techniques of 17.9%. The reasons for discrepant results included MR artifacts, dephasing owing to turbulent flow, site of data acquisition and lobar lung collapse. When using PC-MR to assess pulmonary blood flow ratio, important technical errors occur in a significant proportion of patients who have abnormal pulmonary artery anatomy or pulmonary hypertension. If these technical errors are

  4. Measurement of myocardial perfusion using magnetic resonance

    DEFF Research Database (Denmark)

    Fritz-Hansen, T.; Jensen, L.T.; Larsson, H.B.;

    2008-01-01

    Cardiac magnetic resonance imaging (MRI) has evolved rapidly. Recent developments have made non-invasive quantitative myocardial perfusion measurements possible. MRI is particularly attractive due to its high spatial resolution and because it does not involve ionising radiation. This paper review...... myocardial perfusion imaging with MR contrast agents: methods, validation and experiences from clinical studies. Unresolved issues still restrict the use of these techniques to research although clinical applications are within reach Udgivelsesdato: 2008/12/8......Cardiac magnetic resonance imaging (MRI) has evolved rapidly. Recent developments have made non-invasive quantitative myocardial perfusion measurements possible. MRI is particularly attractive due to its high spatial resolution and because it does not involve ionising radiation. This paper reviews...

  5. Non-invasive epigenetic detection of fetal trisomy 21 in first trimester maternal plasma.

    Directory of Open Access Journals (Sweden)

    Ji Hyae Lim

    Full Text Available BACKGROUND: Down syndrome (DS is the most common known aneuploidy, caused by an extra copy of all or part of chromosome 21. Fetal-specific epigenetic markers have been investigated for non-invasive prenatal detection of fetal DS. The phosphodiesterases gene, PDE9A, located on chromosome 21q22.3, is completely methylated in blood (M-PDE9A and unmethylated in the placenta (U-PDE9A. Therefore, we estimated the accuracy of non-invasive fetal DS detection during the first trimester of pregnancy using this tissue-specific epigenetic characteristic of PDE9A. METHODOLOGY/PRINCIPAL FINDINGS: A nested, case-control study was conducted using maternal plasma samples collected from 108 pregnant women carrying 18 DS and 90 normal fetuses (each case was matched with 5 controls according to gestational weeks at blood sampling. All pregnancies were singletons at or before 12 weeks of gestation between October 2008 and May 2009. The maternal plasma levels of M-PDE9A and U-PDE9A were measured by quantitative methylation-specific polymerase chain reaction. M-PDE9A and U-PDE9A levels were obtained in all samples and did not differ between male and female fetuses. M-PDE9A levels did not differ between the DS cases and controls (1854.3 vs 2004.5 copies/mL; P = 0.928. U-PDE9A levels were significantly elevated in women with DS fetuses compared with controls (356.8 vs 194.7 copies/mL, P<0.001. The sensitivities of U-PDE9A level and the unmethylation index of PDE9A for non-invasive fetal DS detection were 77.8% and 83.3%, respectively, with a 5% false-positive rate. In the risk assessment for fetal DS, the adjusted odds ratios of U-PDE9A level and UI were 46.2 [95% confidence interval: 7.8-151.6] and 63.7 [95% confidence interval: 23.2-206.7], respectively. CONCLUSIONS: Our findings suggest that U-PDE9A level and the unmethylation index of PDE9A may be useful biomarkers for non-invasive fetal DS detection during the first trimester of pregnancy, regardless of fetal

  6. Non-invasive optical detection of HBV based on serum surface-enhanced Raman spectroscopy

    Science.gov (United States)

    Zheng, Zuci; Wang, Qiwen; Weng, Cuncheng; Lin, Xueliang; Lin, Yao; Feng, Shangyuan

    2016-10-01

    An optical method of surface-enhanced Raman spectroscopy (SERS) was developed for non-invasive detection of hepatitis B surface virus (HBV). Hepatitis B virus surface antigen (HBsAg) is an established serological marker that is routinely used for the diagnosis of acute or chronic hepatitis B virus(HBV) infection. Utilizing SERS to analyze blood serum for detecting HBV has not been reported in previous literature. SERS measurements were performed on two groups of serum samples: one group for 50 HBV patients and the other group for 50 healthy volunteers. Blood serum samples are collected from healthy control subjects and patients diagnosed with HBV. Furthermore, principal components analysis (PCA) combined with linear discriminant analysis (LDA) were employed to differentiate HBV patients from healthy volunteer and achieved sensitivity of 80.0% and specificity of 74.0%. This exploratory work demonstrates that SERS serum analysis combined with PCA-LDA has tremendous potential for the non-invasive detection of HBV.

  7. Intrathoracic Pressure Regulation Improves Cerebral Perfusion and Cerebral Blood Flow in a Porcine Model of Brain Injury.

    Science.gov (United States)

    Metzger, Anja; Rees, Jennifer; Kwon, Young; Matsuura, Timothy; McKnite, Scott; Lurie, Keith G

    2015-08-01

    Brain injury is a leading cause of death and disability in children and adults in their most productive years. Use of intrathoracic pressure regulation (IPR) to generate negative intrathoracic pressure during the expiratory phase of positive pressure ventilation improves mean arterial pressure and 24-h survival in porcine models of hemorrhagic shock and cardiac arrest and has been demonstrated to decrease intracranial pressure (ICP) and cerebral perfusion pressure (CPP) in these models. Application of IPR for 240 min in a porcine model of intracranial hypertension (ICH) will increase CPP when compared with controls. Twenty-three female pigs were subjected to focal brain injury by insertion of an epidural Foley catheter inflated with 3 mL of saline. Animals were randomized to treatment for 240 min with IPR set to a negative expiratory phase pressure of -12 cmH2O or no IPR therapy. Intracranial pressure, mean arterial pressure, CPP, and cerebral blood flow (CBF) were evaluated. Intrathoracic pressure regulation significantly improved mean CPP and CBF. Specifically, mean CPP after 90, 120, 180, and 240 min of IPR use was 43.7 ± 2.8 mmHg, 44.0 ± 2.7 mmHg, 44.5 ± 2.8 mmHg, and 43.1 ± 1.9 mmHg, respectively; a significant increase from ICH study baseline (39.5 ± 1.7 mmHg) compared with control animals in which mean CPP was 36.7 ± 1.4 mmHg (ICH study baseline) and then 35.9 ± 2.1 mmHg, 33.7 ± 2.8 mmHg, 33.9 ± 3.0 mmHg, and 36.0 ± 2.7 mmHg at 90, 120, 180, and 240 min, respectively (P blood flow, as measured by an invasive CBF probe, increased in the IPR group (34 ± 4 mL/100 g-min to 49 ± 7 mL/100 g-min at 90 min) but not in controls (27 ± 1 mL/100 g-min to 25 ± 5 mL/100 g-min at 90 min) (P = 0.01). Arterial pH remained unchanged during the entire period of IPR compared with baseline values and control values. In this anesthetized pig model of ICH, treatment with IPR significantly improved CPP and CBF. This therapy may be of clinical value by noninvasively

  8. A non-invasive method of quantifying pancreatic volume in mice using micro-MRI.

    Directory of Open Access Journals (Sweden)

    Jose L Paredes

    Full Text Available In experimental models of pancreatic growth and recovery, changes in pancreatic size are assessed by euthanizing a large cohort of animals at varying time points and measuring organ mass. However, to ascertain this information in clinical practice, patients with pancreatic disorders routinely undergo non-invasive cross-sectional imaging of the pancreas using magnetic resonance imaging (MRI or computed tomography (CT. The aim of the current study was to develop a thin-sliced, optimized sequence protocol using a high field MRI to accurately calculate pancreatic volumes in the most common experimental animal, the mouse. Using a 7 Telsa Bruker micro-MRI system, we performed abdominal imaging in whole-fixed mice in three standard planes: axial, sagittal, and coronal. The contour of the pancreas was traced using Vitrea software and then transformed into a 3-dimensional (3D reconstruction, from which volumetric measurements were calculated. Images were optimized using heart perfusion-fixation, T1 sequence analysis, and 0.2 to 0.4 mm thick slices. As proof of principle, increases in pancreatic volume among mice of different ages correlated tightly with increasing body weight. In summary, this is the first study to measure pancreatic volumes in mice, using a high field 7 Tesla micro-MRI and a thin-sliced, optimized sequence protocol. We anticipate that micro-MRI will improve the ability to non-invasively quantify changes in pancreatic size and will dramatically reduce the number of animals required to serially assess pancreatic growth and recovery.

  9. Intraoperative blood pressure and cerebral perfusion: strategies to clarify hemodynamic goals.

    Science.gov (United States)

    Williams, Monica; Lee, Jennifer K

    2014-07-01

    Blood pressure can vary considerably during anesthesia. If blood pressure falls outside the limits of cerebrovascular autoregulation, children can become at risk of cerebral ischemic or hyperemic injury. However, the blood pressure limits of autoregulation are unclear in infants and children, and these limits can shift after brain injury. This article will review autoregulation, considerations for the hemodynamic management of children with brain injuries, and research on autoregulation monitoring techniques.

  10. Intraoperative blood pressure and cerebral perfusion: strategies to clarify hemodynamic goals

    OpenAIRE

    Williams, Monica; Lee, Jennifer K.

    2014-01-01

    Blood pressure can vary considerably during anesthesia. If blood pressure falls outside the limits of cerebrovascular autoregulation, children can become at risk of cerebral ischemic or hyperemic injury. However, the blood pressure limits of autoregulation are unclear in infants and children, and these limits can shift after brain injury. This article will review autoregulation, considerations for the hemodynamic management of children with brain injuries, and research on autoregulation monit...

  11. Non-invasive measurement of the microvascular properties of non-dysplastic and dysplastic oral leukoplakias by use of optical spectroscopy

    NARCIS (Netherlands)

    Amelink, A.; Sterenborg, H. J. C. M.; Roodenburg, J. L. N.; Witjes, M. J. H.

    2011-01-01

    Differential Path-length Spectroscopy (DPS) was used to non-invasively determine the optical properties of oral leukoplakias in vivo. DPS yields information on microvascular parameters such as the mucosal blood content, the microvascular blood oxygenation and the average micro-vessel diameter as

  12. Non-invasive measurement of the microvascular properties of non-dysplastic and dysplastic oral leukoplakias by use of optical spectroscopy

    NARCIS (Netherlands)

    Amelink, A.; Sterenborg, H. J. C. M.; Roodenburg, J. L. N.; Witjes, M. J. H.

    2011-01-01

    Differential Path-length Spectroscopy (DPS) was used to non-invasively determine the optical properties of oral leukoplakias in vivo. DPS yields information on microvascular parameters such as the mucosal blood content, the microvascular blood oxygenation and the average micro-vessel diameter as wel

  13. Re-thinking resuscitation: Leaving blood pressure cosmetics behind and moving forward to permissive hypotension and a tissue perfusion-based approach

    NARCIS (Netherlands)

    M.W. Dünser (Martin); E.P. Takala; A. Brunauer (Andreas); J. Bakker (Jan)

    2013-01-01

    textabstractDefinitions of shock and resuscitation endpoints traditionally focus on blood pressures and cardiac output. This carries a high risk of overemphasizing systemic hemodynamics at the cost of tissue perfusion. In line with novel shock definitions and evidence of the lack of a correlation be

  14. Modeling function-perfusion behavior in liver lobules including tissue, blood, glucose, lactate and glycogen by use of a coupled two-scale PDE-ODE approach.

    Science.gov (United States)

    Ricken, T; Werner, D; Holzhütter, H G; König, M; Dahmen, U; Dirsch, O

    2015-06-01

    This study focuses on a two-scale, continuum multicomponent model for the description of blood perfusion and cell metabolism in the liver. The model accounts for a spatial and time depending hydro-diffusion-advection-reaction description. We consider a solid-phase (tissue) containing glycogen and a fluid-phase (blood) containing glucose as well as lactate. The five-component model is enhanced by a two-scale approach including a macroscale (sinusoidal level) and a microscale (cell level). The perfusion on the macroscale within the lobules is described by a homogenized multiphasic approach based on the theory of porous media (mixture theory combined with the concept of volume fraction). On macro level, we recall the basic mixture model, the governing equations as well as the constitutive framework including the solid (tissue) stress, blood pressure and solutes chemical potential. In view of the transport phenomena, we discuss the blood flow including transverse isotropic permeability, as well as the transport of solute concentrations including diffusion and advection. The continuum multicomponent model on the macroscale finally leads to a coupled system of partial differential equations (PDE). In contrast, the hepatic metabolism on the microscale (cell level) was modeled via a coupled system of ordinary differential equations (ODE). Again, we recall the constitutive relations for cell metabolism level. A finite element implementation of this framework is used to provide an illustrative example, describing the spatial and time-depending perfusion-metabolism processes in liver lobules that integrates perfusion and metabolism of the liver.

  15. [Abnormal cerebral blood flow distributions during the post-ictal phase of febrile status epilepticus in three pediatric patients measured by arterial spin labeling perfusion MRI].

    Science.gov (United States)

    Hirano, Keiko; Fukuda, Tokiko

    2016-05-01

    The ability to visualize brain perfusion is important for identifying epileptic foci. We present three pediatric cases showing asymmetrical cerebral blood flow (CBF) distributions during the post-ictal phase of febrile status epilepticus measured by arterial spin labeling (ASL) perfusion MRI. During the acute phase, regional CBF measurements in the areas considered including epileptic foci were higher than in the corresponding area of the contralateral hemisphere, though the exact quantitative value varied between cases. We could not identify the correct epileptogenic foci, because those ASL images were taken after the prolonged and extraordinary activation of neurons in the affected area. During the recovery phase, the differences reduced and the average regional CBF measurement was 54.6 ± 6.1 ml/100 g per minute, which was a little less than the number of previous ASL studies. ASL perfusion MRI imaging provides a method for evaluating regional CBF by using magnetically labeled arterial blood water as an endogenous tracer. With this technique, we can repeatedly evaluate both the brain structure and the level of perfusion at the same time. ASL is noninvasive and easily accessible, and therefore it could become a routine tool for assessment of perfusion in daily practice of pediatric neurology.

  16. Towards quantification of blood-flow changes during cognitive task activation using perfusion-based fMRI.

    Science.gov (United States)

    Mildner, Toralf; Zysset, Stefan; Trampel, Robert; Driesel, Wolfgang; Möller, Harald E

    2005-10-01

    Multi-slice perfusion-based functional magnetic resonance imaging (p-fMRI) is demonstrated with a color-word Stroop task as an established cognitive paradigm. Continuous arterial spin labeling (CASL) of the blood in the left common carotid artery was applied for all repetitions of the functional run in a quasi-continuous fashion, i.e., it was interrupted only during image acquisition. For comparison, blood oxygen level dependent (BOLD) contrast was detected using conventional gradient-recalled echo (GE) echo planar imaging (EPI). Positive activations in BOLD imaging appeared in p-fMRI as negative signal changes corresponding to an enhanced transport of inverted water spins into the region of interest, i.e., increased cerebral blood flow (CBF). Regional differences between the localization of activations and the sensitivity of p-fMRI and BOLD-fMRI were observed as, for example, in the inferior frontal sulcus and in the intraparietal sulcus. Quantification of CBF changes during cognitive task activation was performed on a multi-subject basis and yielded CBF increases of the order of 20-30%.

  17. The age-related deficit in LTP is associated with changes in perfusion and blood-brain barrier permeability.

    Science.gov (United States)

    Blau, Christoph W; Cowley, Thelma R; O'Sullivan, Joan; Grehan, Belinda; Browne, Tara C; Kelly, Laura; Birch, Amy; Murphy, Niamh; Kelly, Aine M; Kerskens, Christian M; Lynch, Marina A

    2012-05-01

    In view of the increase in the aging population and the unavoidable parallel increase in the incidence of age-related neurodegenerative diseases, a key challenge in neuroscience is the identification of clinical signatures which change with age and impact on neuronal and cognitive function. Early diagnosis offers the possibility of early therapeutic intervention, thus magnetic resonance imaging (MRI) is potentially a powerful diagnostic tool. We evaluated age-related changes in relaxometry, blood flow, and blood-brain barrier (BBB) permeability in the rat by magnetic resonance imaging and assessed these changes in the context of the age-related decrease in synaptic plasticity. We report that T2 relaxation time was decreased with age; this was coupled with a decrease in gray matter perfusion, suggesting that the observed microglial activation, as identified by increased expression of CD11b, MHCII, and CD68 by immunohistochemistry, flow cytometry, or polymerase chain reaction (PCR), might be a downstream consequence of these changes. Increased permeability of the blood-brain barrier was observed in the perivascular area and the hippocampus of aged, compared with young, rats. Similarly there was an age-related increase in CD45-positive cells by flow cytometry, which are most likely infiltrating macrophages, with a parallel increase in the messenger mRNA expression of chemokines IP-10 and MCP-1. These combined changes may contribute to the deficit in long-term potentiation (LTP) in perforant path-granule cell synapses of aged animals.

  18. The isolated blood-perfused pig ear: an inexpensive and animal-saving model for skin penetration studies.

    Science.gov (United States)

    de Lange, J; van Eck, P; Elliott, G R; de Kort, W L; Wolthuis, O L

    1992-04-01

    To overcome most of the disadvantages of current models to investigate percutaneous penetration of drugs or toxic substances, a model is proposed here based on the isolated pig ear, which is obtained at the slaughterhouse, and perfused with oxygenated blood from the same pig. To determine the viability of the preparations, we measured glucose consumption and lactate production as metabolic parameters, Na+ and K+ ions, as well as lactate dehydrogenase activity in blood as markers for cell damage, whereas vasomotor reactivity was assessed by administering noradrenaline and isoxsuprine. After 60 min of equilibration, only insignificant changes in these parameters were observed during the subsequent 3-hr test period (longer periods were not tested). A slight weight increase was noted during the total period 4 hr, presumably due to slight edema formation. On the basis of several types of measurements, such as in vivo blood flow and ear temperature and in vitro glucose metabolism, standard procedures were developed. It is concluded that this technique offers an easy to handle, cost-efficient, and animal-saving model for skin penetration studies that lacks most of the disadvantages of existing models.

  19. Impact of primary percutaneous coronary intervention on blood perfusion in nonculprit artery in patients with anterior ST elevation myocardial infarction

    Institute of Scientific and Technical Information of China (English)

    WANG Jian; LIU Jing-hua; ZHENG Bin; ZHANG Ming; WANG Shao-ping; ZHENG Ze

    2013-01-01

    Background Recent studies have demonstrated that epicardial flow in nonculprit arteries,which has been assumed to be normal,was slowed in the setting of ST-elevation myocardial infarction (STEMI).However,the impact of primary percutaneous coronary intervention (PCI) on blood perfusion in nonculprit arteries in patients with STEMI has not been clarified.The purpose of this study was to investigate the impact of primary PCI on blood perfusion in nonculprit arteries in patients with STEMI and correlated clinical factors.Methods A total of 117 patients with anterior wall STEMI,the culprit artery being the left anterior descending artery (LAD),undergoing primary PCI (the study group) and 100 patients with normal coronary angiography (the control group) were enrolled.To observe the differences of corrected TIMI frame count (cTFC) and myocardial blush grade (MBG) before and after primary PCI in both culprit and nonculprit arteries,the left circumflex coronary artery (LCX),cTFC and MBG in the LAD and LCX were measured in the study group and control group.The study group was divided into three groups; reflow in the culprit artery group (the R group),no reflow in culprit artery group (the NR group),and no reflow in both the culprit artery and nonculprit artery group (the NRB group) according to MBG grade.The level of serum C-reactive protein (CRP),catecholamine,and fibroblast growth factor-21 (FGF21) were assayed.The clinical and angiographic characteristics were also analyzed.Results cTFC (28.1±24.3 vs.20.3±19.3,P <0.05) and MBG in the LCX were different in the study group compared to the control group before primary PCI.cTFC (25.2±22.3 vs.28.1±24.3,P <0.05) and the MBG level in the LCX were improved after successful primary PCI,but were not recovered to the normal level.Patients with no reflow in the culprit artery had a higher incidence of no-reflow in the nonculprit artery (78% vs.19%,P <0.0001),and the levels of CRP ((3.29±1.31) mg/dl vs.(2.51±1.14) mg

  20. Cerebral hemodynamics in aging : the interplay between blood pressure, cerebral perfusion, and dementia

    NARCIS (Netherlands)

    Claassen, J.A.H.R.

    2008-01-01

    Advances in measurement techniques have made it possible to study dynamic changes in brain blood flow. Transcranial Doppler ultrasonography measures changes in cerebral blood flow-velocity in the larger cerebral arteries (e.g. the middle cerebral artery). Near infrared spectroscopy records changes i

  1. Fast diffuse correlation spectroscopy (DCS) for non-invasive measurement of intracranial pressure (ICP) (Conference Presentation)

    Science.gov (United States)

    Farzam, Parisa; Sutin, Jason; Wu, Kuan-Cheng; Zimmermann, Bernhard B.; Tamborini, Davide; Dubb, Jay; Boas, David A.; Franceschini, Maria Angela

    2017-02-01

    Intracranial pressure (ICP) monitoring has a key role in the management of neurosurgical and neurological injuries. Currently, the standard clinical monitoring of ICP requires an invasive transducer into the parenchymal tissue or the brain ventricle, with possibility of complications such as hemorrhage and infection. A non-invasive method for measuring ICP, would be highly preferable, as it would allow clinicians to promptly monitor ICP during transport and allow for monitoring in a larger number of patients. We have introduced diffuse correlation spectroscopy (DCS) as a non-invasive ICP monitor by fast measurement of pulsatile cerebral blood flow (CBF). The method is similar to Transcranial Doppler ultrasound (TCD), which derives ICP from the amplitude of the pulsatile cerebral blood flow velocity, with respect to the amplitude of the pulsatile arterial blood pressure. We believe DCS measurement is superior indicator of ICP than TCD estimation because DCS directly measures blood flow, not blood flow velocity, and the small cortical vessels measured by DCS are more susceptible to transmural pressure changes than the large vessels. For fast DCS measurements to recover pulsatile CBF we have developed a custom high-power long-coherent laser and a strategy for delivering it to the tissue within ANSI standards. We have also developed a custom FPGA-based correlator board, which facilitates DCS data acquisitions at 50-100 Hz. We have tested the feasibility of measuring pulsatile CBF and deriving ICP in two challenging scenarios: humans and rats. SNR is low in human adults due to large optode distances. It is similarly low in rats because the fast heart rate in this setting requires a high repetition rate.

  2. An alternative non-invasive treatment for Peyronie's disease

    Directory of Open Access Journals (Sweden)

    Joaquim A. Claro

    2004-06-01

    Full Text Available OBJECTIVE: Surgical correction of the deformity and plaque caused by Peyronie's disease has some important disadvantages and extracorporeal shockwave therapy (ESWT emerged as a new promising therapy. We evaluated prospectively the efficacy and safety of the association of high dose vitamin E and ESWT as a non-invasive treatment for the disease. MATERIALS AND METHODS: Twenty-five patients 42 to 68 years old (mean = 54 presenting penile deviation and sexual distress caused by Peyronie's disease were treated in a non-invasive manner. The time of penile deviation ranged from 16 to 52 months (mean = 30. All patients had previous unsuccessful treatment for Peyronie's disease. The angulation's deformity of the penis was assessed by photography at home. The patients received vitamin E (l.200 mg daily during 3 months and underwent 3 to 6 sessions (mean = 3 of ESWT (3,000 to 4,000 shockwaves at a power level of l to 2 at 1-week intervals. RESULTS: From 25 patients treated, 16 (64% reported an improvement in penile angulation, with a mean reduction of 21 degrees (10 to 40. Eight patients reported improvement in their spontaneous erections. Overall, the patients presented only minimal bruising at the site of treatment and skin hematoma. Four patients presented urethral bleeding. The mean angulation after treatment in the control group was 48.67 degrees (30 - 70 and in the study group was 24.42 degrees (0 - 70, statistically significant. CONCLUSION: Considering the common complications and the unsatisfactory outcome of the surgical correction for Peyronie's disease, the association of high dose vitamin E and ESWT represents a good option for a non-invasive, effective and safe treatment of the penile deformity.

  3. Non-invasive pulmonary function test on Morquio patients.

    Science.gov (United States)

    Kubaski, Francyne; Tomatsu, Shunji; Patel, Pravin; Shimada, Tsutomu; Xie, Li; Yasuda, Eriko; Mason, Robert; Mackenzie, William G; Theroux, Mary; Bober, Michael B; Oldham, Helen M; Orii, Tadao; Shaffer, Thomas H

    2015-08-01

    In clinical practice, respiratory function tests are difficult to perform in Morquio syndrome patients due to their characteristic skeletal dysplasia, small body size and lack of cooperation of young patients, where in some cases, conventional spirometry for pulmonary function is too challenging. To establish feasible clinical pulmonary endpoints and determine whether age impacts lung function in Morquio patients non-invasive pulmonary tests and conventional spirometry were evaluated. The non-invasive pulmonary tests: impulse oscillometry system, pneumotachography, and respiratory inductance plethysmography in conjunction with conventional spirometry were evaluated in twenty-two Morquio patients (18 Morquio A and 4 Morquio B) (7 males), ranging from 3 to 40 years of age. Twenty-two patients were compliant with non-invasive tests (100%) with the exception of IOS (81.8%-18 patients). Seventeen patients (77.3%) were compliant with spirometry testing. All subjects had normal vital signs at rest including >95% oxygen saturation, end tidal CO2 (38-44 mmHg), and age-appropriate heart rate (mean=98.3, standard deviation=19) (two patients were deviated). All patients preserved normal values in the impulse oscillometry system, pneumotachography, and respiratory inductance plethysmography, although predicted forced expiratory total (72.8±6.9 SE%) decreased with age and was below normal; phase angle (35.5±16.5°), %rib cage (41.6±12.7%), resonant frequency, and forced expiratory volume in 1 s/forced expiratory volume total (110.0±3.2 SE%) were normal and not significantly impacted by age. The proposed non-invasive pulmonary function tests are able to cover a greater number of patients (young patients and/or wheel-chair bound), thus providing a new diagnostic approach for the assessment of lung function in Morquio syndrome which in many cases may be difficult to evaluate. Morquio patients studied herein demonstrated no clinical or functional signs of restrictive and

  4. Towards a smart non-invasive fluid loss measurement system.

    Science.gov (United States)

    Suryadevara, N K; Mukhopadhyay, S C; Barrack, L

    2015-04-01

    In this article, a smart wireless sensing non-invasive system for estimating the amount of fluid loss, a person experiences while physical activity is presented. The system measures three external body parameters, Heart Rate, Galvanic Skin Response (GSR, or skin conductance), and Skin Temperature. These three parameters are entered into an empirically derived formula along with the user's body mass index, and estimation for the amount of fluid lost is determined. The core benefit of the developed system is the affluence usage in combining with smart home monitoring systems to care elderly people in ambient assisted living environments as well in automobiles to monitor the body parameters of a motorist.

  5. Cell-baswd non-invasive prenatal testing

    DEFF Research Database (Denmark)

    Uldbjerg, Niels; Singh, Ripudaman; Christensen, Rikke

    CONTROL ID: 2520273 ABSTRACT FINAL ID: OC06.03 TITLE: Cell based Non-invasive Prenatal Testing (NIPT) AUTHORS (FIRST NAME, LAST NAME): Niels Uldbjerg2, Ripudaman Singh4, Rikke Christensen3, Palle Schelde4, Ida Vogel1, Else Marie Vestergaard3, Lotte Hatt4, Steen Kølvrå4 INSTITUTIONS (ALL): 1....... Department of Clinical Genetics, Aarhus University Hospital, Aarhus N, none, Denmark. 2. Obstetrics and Gynecology, Aarhus University Hospital Skejby, Aarhus, Denmark. 3. Clinical Genetics, Aarhus University Hospital, Aarhus, Denmark. 4. Arcedi Biotech Aps, Aarhus, Denmark. ABSTRACT BODY: Objectives: NIPT...

  6. PEEP in non invasive ventilatory treatment of worsened BPCO

    Directory of Open Access Journals (Sweden)

    Federico Lari

    2009-08-01

    Full Text Available Acute respiratory failure due to exacerbation of chronic pulmonary disease is usually treated with bilevel pressure non invasive ventilation. An high inspiratory pressure is used to improve tidal volume, a lower expiratory pressure is used to neutralize end expiratory positive pressure of patient (PEEPi caused by flow limitation and airway trapping. When ventilators for bilevel pressure ventilation are not available, is useful to administer to patient an external low (5cmH2O positive pressure with simple CPAP systems (Continuous Positive Airway Pressure, such as Venturi like flow generator largely available and well known everywhere.

  7. Biomechanics of subcellular structures by non-invasive Brillouin microscopy

    Science.gov (United States)

    Antonacci, Giuseppe; Braakman, Sietse

    2016-11-01

    Cellular biomechanics play a pivotal role in the pathophysiology of several diseases. Unfortunately, current methods to measure biomechanical properties are invasive and mostly limited to the surface of a cell. As a result, the mechanical behaviour of subcellular structures and organelles remains poorly characterised. Here, we show three-dimensional biomechanical images of single cells obtained with non-invasive, non-destructive Brillouin microscopy with an unprecedented spatial resolution. Our results quantify the longitudinal elastic modulus of subcellular structures. In particular, we found the nucleoli to be stiffer than both the nuclear envelope (p biomechanics and its role in pathophysiology.

  8. Quantitative analysis of CT-perfusion parameters in the evaluation of brain gliomas and metastases

    Directory of Open Access Journals (Sweden)

    Di Nallo Anna

    2009-03-01

    Full Text Available Abstract Background The paper reports a quantitative analysis of the perfusion maps of 22 patients, affected by gliomas or by metastasis, with the aim of characterizing the malignant tissue with respect to the normal tissue. The gold standard was obtained by histological exam or nuclear medicine techniques. The perfusion scan provided 11 parametric maps, including Cerebral Blood Volume (CBV, Cerebral Blood Flow (CBF, Average Perfusion (Pmean and Permeability-surface area product (PS. Methods The perfusion scans were performed after the injection of 40 ml of non-ionic contrast agent, at an injection rate of 8 ml/s, and a 40 s cine scan with 1 s interval was acquired. An expert radiologist outlined the region of interest (ROI on the unenhanced CT scan, by using a home-made routine. The mean values with their standard deviations inside the outlined ROIs and the contralateral ROIs were calculated on each map. Statistical analyses were used to investigate significant differences between diseased and normal regions. Receiving Operating Characteristic (ROC curves were also generated. Results Tumors are characterized by higher values of all the perfusion parameters, but after the statistical analysis, only the PS, PatRsq (Patlak Rsquare and Tpeak (Time to Peak resulted significant. ROC curves, confirmed both PatRsq and PS as equally reliable metrics for discriminating between malignant and normal tissues, with areas under curves (AUCs of 0.82 and 0.81, respectively. Conclusion CT perfusion is a useful and non invasive technique for evaluating brain neoplasms. Malignant and normal tissues can be accurately differentiated using perfusion map, with the aim of performing tumor diagnosis and grading, and follow-up analysis.

  9. CARDIAC TRANSPLANT REJECTION AND NON-INVASIVE COMON CAROTID ARTERY WALL FUNCTIONAL INDICES

    Directory of Open Access Journals (Sweden)

    A. O. Shevchenko

    2015-01-01

    Full Text Available Allograft rejection would entail an increase in certain blood biomarkers and active substances derived from activated inflammatory cells which could influence entire vascular endothelial function and deteriorate arterial wall stiffness. We propose that carotid wall functional indices measured with non-invasive ultrasound could we valuable markers of the subclinical cardiac allograft rejection. Aim. Our goal was to analyze the clinical utility of functional common carotid wall (CCW variables measured with high-resolution Doppler ultrasound as a non-invasive screening tool for allograft rejection in cardiac transplant patients (pts. Methods. One hundred and seventy one pts included 93 cardiac recipients, 30 dilated cardiomyopathy waiting list pts, and 48 stable coronary artery disease (SCAD pts without decompensated heart failure were included. Along with resistive index (Ri, pulsative index (Pi, and CCW intima-media thickness (IMT, CCW rigidity index (iRIG was estimated using empirical equation. Non-invasive evaluation was performed in cardiac transplant recipients prior the endomyo- cardial biopsy. Results. Neither of Ri, Pi, or CCW IMT were different in studied subgroups. iRIG was signifi- cantly lower in SCAD pts when compared to the dilated cardiomyopathy subgroup. The later had similar values with cardiac transplant recipients without rejection. Antibody-mediated and cellular rejection were found in 22 (23.7% and 17 (18.3% cardiac recipients, respectively. Mean iRIG in pts without rejection was significantly lower in comparison to antibody-mediated rejection and cell-mediated (5514.7 ± 2404.0 vs 11856.1 ± 6643.5 and 16071.9 ± 10029.1 cm/sec2, respectively, p = 0.001. Area under ROC for iRIG was 0.90 ± 0.03 units2. Analysis showed that iRIG values above estimated treshold 7172 cm/sec2 suggested relative risk of any type of rejection 17.7 (95%CI = 6.3–49.9 sensitivity 80.5%, specificity – 81.1%, negative predictive value – 84

  10. The Epigenome View: An Effort towards Non-Invasive Prenatal Diagnosis

    Directory of Open Access Journals (Sweden)

    Elisavet A. Papageorgiou

    2014-04-01

    Full Text Available Epigenetic modifications have proven to play a significant role in cancer development, as well as fetal development. Taking advantage of the knowledge acquired during the last decade, great interest has been shown worldwide in deciphering the fetal epigenome towards the development of methylation-based non-invasive prenatal tests (NIPT. In this review, we highlight the different approaches implemented, such as sodium bisulfite conversion, restriction enzyme digestion and methylated DNA immunoprecipitation, for the identification of differentially methylated regions (DMRs between free fetal DNA found in maternal blood and DNA from maternal blood cells. Furthermore, we evaluate the use of selected DMRs identified towards the development of NIPT for fetal chromosomal aneuploidies. In addition, we perform a comparison analysis, evaluate the performance of each assay and provide a comprehensive discussion on the potential use of different methylation-based technologies in retrieving the fetal methylome, with the aim of further expanding the development of NIPT assays.

  11. Quantitative non-invasive intracellular imaging of Plasmodium falciparum infected human erythrocytes

    Science.gov (United States)

    Edward, Kert; Farahi, Faramarz

    2014-05-01

    Malaria is a virulent pathological condition which results in over a million annual deaths. The parasitic agent Plasmodium falciparum has been extensively studied in connection with this epidemic but much remains unknown about its development inside the red blood cell host. Optical and fluorescence imaging are among the two most common procedures for investigating infected erythrocytes but both require the introduction of exogenous contrast agents. In this letter, we present a procedure for the non-invasive in situ imaging of malaria infected red blood cells. The procedure is based on the utilization of simultaneously acquired quantitative phase and independent topography data to extract intracellular information. Our method allows for the identification of the developmental stages of the parasite and facilitates in situ analysis of the morphological changes associated with the progression of this disease. This information may assist in the development of efficacious treatment therapies for this condition.

  12. Full-field laser Doppler imaging and its physiological significance for tissue blood perfusion

    Science.gov (United States)

    Binzoni, T.; Van DeVille, D.

    2008-12-01

    Using Monte Carlo simulations for a semi-infinite medium representing a skeletal muscle tissue, it is demonstrated that the zero- and first-order moments of the power spectrum for a representative pixel of a full-field laser-Doppler imager behave differently from classical laser-Doppler flowmetry. In particular, the zero-order moment has a very low sensitivity to tissue blood volume changes, and it becomes completely insensitive if the probability for a photon to interact with a moving red blood cell is above 0.05. It is shown that the loss in sensitivity is due to the strong forward scatter of the propagating photons in biological tissues (i.e., anisotropy factor g = 0.9). The first-order moment is linearly related to the root mean square of the red blood cell velocity (the Brownian component), and there is also a positive relationship with tissue blood volume. The most common physiological interpretation of the first-order moment is as tissue blood volume times expectation of the blood velocity (in probabilistic terms). In this sense, the use of the first-order moment appears to be a reasonable approach for qualitative real-time blood flow monitoring, but it does not allow us to obtain information on blood velocity or volume independently. Finally, it is shown that the spatial and temporal resolution trade-off imposed by the CMOS detectors, used in full-field laser-Doppler hardware, may lead to measurements that vary oppositely with the underlying physiological quantities. Further improvements on detectors' sampling rate will overcome this limitation.

  13. Full-field laser-Doppler imaging and its physiological significance for tissue blood perfusion

    Energy Technology Data Exchange (ETDEWEB)

    Binzoni, T [Departement des Neurosciences Fondamentales, University of Geneva (Switzerland); Ville, D van de [Biomedical Imaging Group, Ecole Polytechnique Federale de Lausanne (EPFL) (Switzerland)], E-mail: Tiziano.Binzoni@medecine.unige.ch

    2008-12-07

    Using Monte Carlo simulations for a semi-infinite medium representing a skeletal muscle tissue, it is demonstrated that the zero- and first-order moments of the power spectrum for a representative pixel of a full-field laser-Doppler imager behave differently from classical laser-Doppler flowmetry. In particular, the zero-order moment has a very low sensitivity to tissue blood volume changes, and it becomes completely insensitive if the probability for a photon to interact with a moving red blood cell is above 0.05. It is shown that the loss in sensitivity is due to the strong forward scatter of the propagating photons in biological tissues (i.e., anisotropy factor g = 0.9). The first-order moment is linearly related to the root mean square of the red blood cell velocity (the Brownian component), and there is also a positive relationship with tissue blood volume. The most common physiological interpretation of the first-order moment is as tissue blood volume times expectation of the blood velocity (in probabilistic terms). In this sense, the use of the first-order moment appears to be a reasonable approach for qualitative real-time blood flow monitoring, but it does not allow us to obtain information on blood velocity or volume independently. Finally, it is shown that the spatial and temporal resolution trade-off imposed by the CMOS detectors, used in full-field laser-Doppler hardware, may lead to measurements that vary oppositely with the underlying physiological quantities. Further improvements on detectors' sampling rate will overcome this limitation.

  14. Antibody-dependent transplacental transfer of malaria blood-stage antigen using a human ex vivo placental perfusion model.

    Directory of Open Access Journals (Sweden)

    Karen May

    Full Text Available Prenatal exposure to allergens or antigens released by infections during pregnancy can stimulate an immune response or induce immunoregulatory networks in the fetus affecting susceptibility to infection and disease later in life. How antigen crosses from the maternal to fetal environment is poorly understood. One hypothesis is that transplacental antigen transfer occurs as immune complexes, via receptor-mediated transport across the syncytiotrophoblastic membrane and endothelium of vessels in fetal villi. This hypothesis has never been directly tested. Here we studied Plasmodium falciparum merozoite surface protein 1 (MSP1 that is released upon erythrocyte invasion. We found MSP1 in cord blood from a third of newborns of malaria-infected women and in >90% following treatment with acid dissociation demonstrating MSP1 immune complexes. Using an ex vivo human placental model that dually perfuses a placental cotyledon with independent maternal and fetal circuits, immune-complexed MSP1 transferred from maternal to fetal circulation. MSP1 alone or with non-immune plasma did not transfer; pre-incubation with human plasma containing anti-MSP1 was required. MSP1 bound to IgG was detected in the fetal perfusate. Laser scanning confocal microscopy demonstrated MSP1 in the fetal villous stroma, predominantly in fetal endothelial cells. MSP1 co-localized with IgG in endothelial cells, but not with placental macrophages. Thus we show, for the first time, antibody-dependent transplacental transfer of an antigen in the form of immune complexes. These studies imply frequent exposure of the fetus to certain antigens with implications for management of maternal infections during pregnancy and novel approaches to deliver vaccines or drugs to the fetus.

  15. Added value of lung perfused blood volume images using dual-energy CT for assessment of acute pulmonary embolism

    Energy Technology Data Exchange (ETDEWEB)

    Okada, Munemasa, E-mail: radokada@yamaguchi-u.ac.jp [Department of Radiology, Yamaguchi University Graduate School of Medicine, 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan); Kunihiro, Yoshie [Department of Radiology, Yamaguchi University Graduate School of Medicine, 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan); Nakashima, Yoshiteru [Department of Radiology, Yamaguchi Grand Medical Center, Oosaki 77, Hofu, Yamaguchi 747-8511 (Japan); Nomura, Takafumi [Department of Radiology, Yamaguchi University Graduate School of Medicine, 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan); Kudomi, Shohei; Yonezawa, Teppei [Department of Radiology, Yamaguchi University Hospital, 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan); Suga, Kazuyoshi [Department of Radiology, St. Hills Hospital, Imamurakita 3-7-18, Ube, Yamaguchi 755-0155 (Japan); Matsunaga, Naofumi [Department of Radiology, Yamaguchi University Graduate School of Medicine, 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan)

    2015-01-15

    Purpose: To investigate the added value of lung perfused blood volume (LPBV) using dual-energy CT for the evaluation of intrapulmonary clot (IPC) in patients suspected of having acute pulmonary embolism (PE). Materials and methods: Institutional review board approval was obtained for this retrospective study. Eighty-three patients suspected of having PE who underwent CT pulmonary angiography (CTPA) using a dual-energy technique were enrolled in this study. Two radiologists who were blinded retrospectively and independently reviewed CTPA images alone and the combined images with color-coded LPBV over a 4-week interval, and two separate sessions were performed with a one-month interval. Inter- and intraobserver variability and diagnostic accuracy were evaluated for each reviewer with receiver operating characteristic (ROC) curve analysis. Results: Values for inter- and intraobserver agreement, respectively, were better for CTPA combined with LPBV (ICC = 0.847 and 0.937) than CTPA alone (ICC = 0.748 and 0.861). For both readers, diagnostic accuracy (area under the ROC curve [A{sub z}]) were also superior, when CTPA alone (A{sub z} = 0.888 [reader 1] and 0.912 [reader 2]) was compared with that after the combination with LPBV images (A{sub z} = 0.966 [reader 1] and 0.959 [reader 2]) (p < 0.001). However, A{sub z} values of both images might not have significant difference in statistics, because A{sub z} value of CTPA alone was high and 95% confidence intervals overlapped in both images. Conclusion: Addition of dual-energy perfusion CT to CTPA improves detection of peripheral IPCs with better interobserver agreement.

  16. Near-infrared spectroscopy and indocyanine green derived blood flow index for noninvasive measurement of muscle perfusion during exercise.

    Science.gov (United States)

    Habazettl, Helmut; Athanasopoulos, Dimitris; Kuebler, Wolfgang M; Wagner, Harrieth; Roussos, Charis; Wagner, Peter D; Ungruhe, Juergen; Zakynthinos, Spyros; Vogiatzis, Ioannis

    2010-04-01

    Near-infrared spectroscopy (NIRS) with the tracer indocyanine green (ICG) may be used for measuring muscle blood flow (MBF) during exercise, if arterial ICG concentration is measured simultaneously. Although pulse dye densitometry allows for noninvasive measurement of arterial dye concentration, this technique is sensitive to motion and may not be applicable during exercise. The aim of this study was to evaluate a noninvasive blood flow index (BFI), which is derived solely from the muscle ICG concentration curve. In 10 male cyclists 5 mg ICG were injected into an antecubital vein at rest and during cycling at 30, 60, 70, 80, 90, and 100% of previously determined maximal work load. Simultaneously blood was withdrawn through a photodensitometer at 20 ml/min from the radial artery to measure arterial ICG concentration. To measure muscle tissue ICG concentrations, two sets of NIRS optodes were positioned on the skin, one over the left seventh intercostal space and the other over the left vastus lateralis muscle. MBF was calculated from the arterial and muscle concentration data according to Fick's principle. BFI was calculated solely from the muscle concentration curve as ICG concentration difference divided by rise time between 10 and 90% of peak. During exercise mean BFI values changed similarly to MBF in both intercostal and quadriceps muscles and showed excellent correlations with MBF: r = 0.98 and 0.96, respectively. Individual data showed some scattering among BFI and MBF values but still reasonable correlations of BFI with MBF: r = 0.73 and 0.72 for intercostal and quadriceps muscles, respectively. Interobserver variability, as analyzed by Bland-Altman plots, was considerably less for BFI than MBF. These data suggest that BFI can be used for measuring changes in muscle perfusion from rest to maximal exercise. Although absolute blood flow cannot be determined, BFI has the advantages of being essentially noninvasive and having low interobserver variability.

  17. Magnetic resonance perfusion imaging without contrast media

    Energy Technology Data Exchange (ETDEWEB)

    Martirosian, Petros; Graf, Hansjoerg; Schick, Fritz [University Hospital of Tuebingen, Section on Experimental Radiology, Tuebingen (Germany); Boss, Andreas; Schraml, Christina; Schwenzer, Nina F.; Claussen, Claus D. [University Hospital of Tuebingen, Department of Diagnostic and Interventional Radiology, Tuebingen (Germany)

    2010-08-15

    Principles of magnetic resonance imaging techniques providing perfusion-related contrast weighting without administration of contrast media are reported and analysed systematically. Especially common approaches to arterial spin labelling (ASL) perfusion imaging allowing quantitative assessment of specific perfusion rates are described in detail. The potential of ASL for perfusion imaging was tested in several types of tissue. After a systematic comparison of technical aspects of continuous and pulsed ASL techniques the standard kinetic model and tissue properties of influence to quantitative measurements of perfusion are reported. For the applications demonstrated in this paper a flow-sensitive alternating inversion recovery (FAIR) ASL perfusion preparation approach followed by true fast imaging with steady precession (true FISP) data recording was developed and implemented on whole-body scanners operating at 0.2, 1.5 and 3 T for quantitative perfusion measurement in various types of tissue. ASL imaging provides a non-invasive tool for assessment of tissue perfusion rates in vivo. Images recorded from kidney, lung, brain, salivary gland and thyroid gland provide a spatial resolution of a few millimetres and sufficient signal to noise ratio in perfusion maps after 2-5 min of examination time. Newly developed ASL techniques provide especially high image quality and quantitative perfusion maps in tissues with relatively high perfusion rates (as also present in many tumours). Averaging of acquisitions and image subtraction procedures are mandatory, leading to the necessity of synchronization of data recording to breathing in abdominal and thoracic organs. (orig.)

  18. Sub-band denoising and spline curve fitting method for hemodynamic measurement in perfusion MRI

    Science.gov (United States)

    Lin, Hong-Dun; Huang, Hsiao-Ling; Hsu, Yuan-Yu; Chen, Chi-Chen; Chen, Ing-Yi; Wu, Liang-Chi; Liu, Ren-Shyan; Lin, Kang-Ping

    2003-05-01

    In clinical research, non-invasive MR perfusion imaging is capable of investigating brain perfusion phenomenon via various hemodynamic measurements, such as cerebral blood volume (CBV), cerebral blood flow (CBF), and mean trasnit time (MTT). These hemodynamic parameters are useful in diagnosing brain disorders such as stroke, infarction and periinfarct ischemia by further semi-quantitative analysis. However, the accuracy of quantitative analysis is usually affected by poor signal-to-noise ratio image quality. In this paper, we propose a hemodynamic measurement method based upon sub-band denoising and spline curve fitting processes to improve image quality for better hemodynamic quantitative analysis results. Ten sets of perfusion MRI data and corresponding PET images were used to validate the performance. For quantitative comparison, we evaluate gray/white matter CBF ratio. As a result, the hemodynamic semi-quantitative analysis result of mean gray to white matter CBF ratio is 2.10 +/- 0.34. The evaluated ratio of brain tissues in perfusion MRI is comparable to PET technique is less than 1-% difference in average. Furthermore, the method features excellent noise reduction and boundary preserving in image processing, and short hemodynamic measurement time.

  19. Distribution of emm types in invasive and non-invasive group A and G streptococci.

    Science.gov (United States)

    Vähäkuopus, S; Vuento, R; Siljander, T; Syrjänen, J; Vuopio, J

    2012-06-01

    Our study describes the emm type distributions of invasive and non-invasive group A streptococci (GAS) and group G streptococci (GGS) strains in one of the biggest Health Districts in Finland. A total of 571 GAS or GGS were recovered from patients with invasive or non-invasive infections during a 1-year period in 2008-2009 in Pirkanmaa Health District in Finland. We describe here the emm type distributions of GAS and GGS collected from throat (n = 246), pus (n = 217), deep tissue (n = 56) and blood (n = 52). The most common emm types among GAS were emm77, emm1, emm28, emm89 and emm12. Among GGS, the most common emm types were stG480, stG643, stG6, stC6979 and stG485. Some emm types were found to associate with certain infection focus. In GAS, emm77 associated with pus isolates, whereas emm1 and emm12 were more frequent among throat isolates. In GGS, stG480 was more commonly found from throat isolates.

  20. Non-Invasive Detection of Anaemia Using Digital Photographs of the Conjunctiva.

    Science.gov (United States)

    Collings, Shaun; Thompson, Oliver; Hirst, Evan; Goossens, Louise; George, Anup; Weinkove, Robert

    2016-01-01

    Anaemia is a major health burden worldwide. Although the finding of conjunctival pallor on clinical examination is associated with anaemia, inter-observer variability is high, and definitive diagnosis of anaemia requires a blood sample. We aimed to detect anaemia by quantifying conjunctival pallor using digital photographs taken with a consumer camera and a popular smartphone. Our goal was to develop a non-invasive screening test for anaemia. The conjunctivae of haemato-oncology in- and outpatients were photographed in ambient lighting using a digital camera (Panasonic DMC-LX5), and the internal rear-facing camera of a smartphone (Apple iPhone 5S) alongside an in-frame calibration card. Following image calibration, conjunctival erythema index (EI) was calculated and correlated with laboratory-measured haemoglobin concentration. Three clinicians independently evaluated each image for conjunctival pallor. Conjunctival EI was reproducible between images (average coefficient of variation 2.96%). EI of the palpebral conjunctiva correlated more strongly with haemoglobin concentration than that of the forniceal conjunctiva. Using the compact camera, palpebral conjunctival EI had a sensitivity of 93% and 57% and specificity of 78% and 83% for detection of anaemia (haemoglobin anaemia. Erythema index of the palpebral conjunctiva calculated from images taken with a compact camera or mobile phone correlates with haemoglobin and compares favourably to clinician assessment for prediction of anaemia. If confirmed in further series, this technique may be useful for the non-invasive screening for anaemia.

  1. High-precision, non-invasive anti-microvascular approach via concurrent ultrasound and laser irradiation

    Science.gov (United States)

    Hu, Zizhong; Zhang, Haonan; Mordovanakis, Aghapi; Paulus, Yannis M.; Liu, Qinghuai; Wang, Xueding; Yang, Xinmai

    2017-01-01

    Antivascular therapy represents a proven strategy to treat angiogenesis. By applying synchronized ultrasound bursts and nanosecond laser irradiation, we developed a novel, selective, non-invasive, localized antivascular method, termed photo-mediated ultrasound therapy (PUT). PUT takes advantage of the high native optical contrast among biological tissues and can treat microvessels without causing collateral damage to the surrounding tissue. In a chicken yolk sac membrane model, under the same ultrasound parameters (1 MHz at 0.45 MPa and 10 Hz with 10% duty cycle), PUT with 4 mJ/cm2 and 6 mJ/cm2 laser fluence induced 51% (p = 0.001) and 37% (p = 0.018) vessel diameter reductions respectively. With 8 mJ/cm2 laser fluence, PUT would yield vessel disruption (90%, p cavitation may play a role in PUT. In conclusion, PUT holds significant promise as a novel non-invasive antivascular method with the capability to precisely target blood vessels.

  2. 肾透明细胞癌多层螺旋CT灌注成像血流灌注的定量诊断价值%Quantitative study of suprarenal epithelioma by CT perfusion imaging and blood perfusion

    Institute of Scientific and Technical Information of China (English)

    牛玉军; 张祥林

    2011-01-01

    Objective To approach quantitative diagnostic value of MSCT perfusion imaging in blood perfusion of suprarenal epithelioma.Methods 58 cases of MSCT perfusion imaging data of suprarenal epithelioma proved by operation were analyzed and blood perfusion imaging both cancer and normal nephridial tissue opposite side were demonstrated.Blood flow( BF), blood volume( BV), mean transit time (MTT) and permeability coefficient(PS) both in active part of tumor and normal nephridial tissue opposite side were calculated.Results There was significant statistical difference in BF, BV, MTT and PS between tumor and normal tissue ( P < 0.01 ).Conclusions MSCT perfusion imaging can complete the quantitative assessment to haemodynamics variation of suprarenal epithelioma and it also can reflect appearance and function of tumor and decide prognosis.%目的 探讨多层螺旋CT(MSCT)灌注成像对肾透明细胞癌血流灌注的定量诊断价值.方法 回顾性分析经手术病理证实的肾透明细胞癌58例MSCT灌注扫描数据,使用256彩色直观显示癌组织及对侧正常肾组织血流灌注图,分别计算出肿瘤生长活跃部分及对侧正常肾皮质血流量(BF)、血容量(BV)、对比剂平均通过时间(MTT)及毛细血管表面通透系数(PS),并进行对比分析、定量研究.结果 肿瘤生长活跃部分的BF、BV、MTT、PS与对侧肾皮质各灌注参数间均有显著差异(P<0.01).结论 MSCT灌注成像能定量评价肾透明细胞癌的血流动力学变化,同时反映肿瘤的形态和功能,并能判断预后.

  3. Non-invasive Respiratory Support in Blunt Chest Injury

    Directory of Open Access Journals (Sweden)

    T. V. Lobus

    2006-01-01

    Full Text Available Objective. To optimize the results of treatment in patients with acute respiratory failure (ARF due to lung contusion, by using the methods of non-invasive mask respiratory support. Materials and methods. The study covered 31 patients with severe blunt chest injury, multiple costal fractures, and hypoxemic ARF. The patients underwent assisted ventilation (AV in the CPAP+PSV mode through a facial or nasal mask. Physiological parameters were recorded during non-invasive mask ventilation (NIMV in the stepwise fashion. A control group comprised 25 patients with the similar severity of injury and ARF who were given conventional AV.Results. In 67.7% of the study group patients, NIMV was effective in improving oxygenation and external respiration, without exerting negative hemodynamic effects. Endotracheal intubation and AV could be avoided in these patients. Comparison of the study and control groups revealed a significant reduction in the incidence of secondary pneumonias in the NIMV group and in the duration of treatment. Mask ventilation could decrease mortality from 44% in the control group to 9.7% in the NIMV group.Conclusion. NIMV applied to patients with hypoxemic ARF in the presence of lung contusion improves pulmonary function and, in the bulk of patients, allows endotracheal intubation and AV and consequently their associated complications. When mask ventilation is employed, management of patients becomes shorter and simpler and mortality rates substantially decrease. 

  4. Sleep-related breathing disorders and non-invasive ventilation

    Directory of Open Access Journals (Sweden)

    Agata Lax

    2015-05-01

    Full Text Available Non-invasive mechanical ventilation (NPPV was originally used in patients with acute respiratory impairment or exacerbations of chronic respiratory diseases, as an alternative to the endotracheal tube. Over the last thirty years NPPV has been also used at night in patients with stable chronic lung disease such as obstructive sleep apnea, the overlap syndrome (chronic obstructive pulmonary disease and obstructive sleep apnea, neuromuscular disorders, obesity-hypoventilation syndrome, and in other conditions such as sleep disorders associated with congestive heart failure (Cheyne-Stokes respiration. In this no-systematic review we discuss the different types of NPPV, the specific conditions in which they can be used and the indications, recommendations and evidence supporting the efficacy of NPPV. Optimizing patient acceptance and adherence to non-invasive ventilation treatment is challenging. The treatment of sleep-related disorders is a life-threatening condition. The optimal level of treatment should be determined in a sleep laboratory. Side effects directly affecting the patient’s adherence to treatment are known. The most common are nasopharyngeal symptoms including increased congestion and rhinorrhea; these effects are related to reduced humidity of inspired gas. Humidification of delivered gas may improve these symptoms.

  5. Non-invasive diagnostic imaging of colorectal liver metastases

    Institute of Scientific and Technical Information of China (English)

    Pier; Paolo; Mainenti; Federica; Romano; Laura; Pizzuti; Sabrina; Segreto; Giovanni; Storto; Lorenzo; Mannelli; Massimo; Imbriaco; Luigi; Camera; Simone; Maurea

    2015-01-01

    Colorectal cancer is one of the few malignant tumors in which synchronous or metachronous liver metastases [colorectal liver metastases(CRLMs)] may be treated with surgery. It has been demonstrated that resection of CRLMs improves the long-term prognosis. On the other hand, patients with un-resectable CRLMs may benefit from chemotherapy alone or in addition to liverdirected therapies. The choice of the most appropriate therapeutic management of CRLMs depends mostly on the diagnostic imaging. Nowadays, multiple non-invasive imaging modalities are available and those have a pivotal role in the workup of patients with CRLMs. Although extensive research has been performed with regards to the diagnostic performance of ultrasonography, computed tomography, positron emission tomography and magnetic resonance for the detection of CRLMs, the optimal imaging strategies for staging and follow up are still to be established. This largely due to the progressive technological and pharmacological advances which are constantly improving the accuracy of each imaging modality. This review describes the non-invasive imaging approaches of CRLMs reporting the technical features, the clinical indications, the advantages and the potential limitations of each modality, as well as including some information on the development of new imaging modalities, the role of new contrast media and the feasibility of using parametric image analysis as diagnostic marker of presence of CRLMs.

  6. Influence of hemoglobin on non-invasive optical bilirubin sensing

    Science.gov (United States)

    Jiang, Jingying; Gong, Qiliang; Zou, Da; Xu, Kexin

    2012-03-01

    Since the abnormal metabolism of bilirubin could lead to diseases in the human body, especially the jaundice which is harmful to neonates. Traditional invasive measurements are difficult to be accepted by people because of pain and infection. Therefore, the real-time and non-invasive measurement of bilirubin is of great significance. However, the accuracy of currently transcutaneous bilirubinometry(TcB) is generally not high enough, and affected by many factors in the human skin, mostly by hemoglobin. In this talk, absorption spectra of hemoglobin and bilirubin have been collected and analyzed, then the Partial Least Squares (PLS) models have been built. By analyzing and comparing the Correlation and Root Mean Square Error of Prediction(RMSEP), the results show that the Correlation of bilirubin solution model is larger than that of the mixture solution added with hemoglobin, and its RMSEP value is smaller than that of mixture solution. Therefore, hemoglobin has influences on the non-invasive optical bilirubin sensing. In next step, it is necessary to investigate how to eliminate the influence.

  7. Non-invasive measurement of oxygen diffusion in model foods.

    Science.gov (United States)

    Bhunia, Kanishka; Sablani, Shyam S; Tang, Juming; Rasco, Barbara

    2016-11-01

    In this study, we developed a non-invasive method to determine oxygen diffusivity (DO2) in food gels using an Oxydot luminescence sensor. We designed and fabricated a transparent diffusion cell in order to represent oxygen transfer into foods packaged in an 8-ounce polymeric tray. Oxydots were glued to the sides (side-dot) and bottom (bottom-dot) of the cell and filled with 1, 2, and 3% (w/v) agar gel as a model food. After deoxygenation, local oxygen concentrations in the gels were measured non-invasively at 4, 12 and 22°C. Effective oxygen diffusivities in gels (DO2g) and water (DO2w) were obtained after fitting experimental data to the analytical solution (data from side-dot) and the numerical solution (data from bottom-dot) to Fick's second law. Temperature had significant positive influence (P0.05) was found between the activation energy (Ea) of water and gels (1-3% w/v) for temperatures ranging from 4 to 22°C. We used a combined obstruction and hydrodynamic model to explain why DO2g decreased as gel concentration increased. The method developed in this study can be used to study the oxygen diffusivity in foods. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Non-invasive diagnostic imaging of colorectal liver metastases.

    Science.gov (United States)

    Mainenti, Pier Paolo; Romano, Federica; Pizzuti, Laura; Segreto, Sabrina; Storto, Giovanni; Mannelli, Lorenzo; Imbriaco, Massimo; Camera, Luigi; Maurea, Simone

    2015-07-28

    Colorectal cancer is one of the few malignant tumors in which synchronous or metachronous liver metastases [colorectal liver metastases (CRLMs)] may be treated with surgery. It has been demonstrated that resection of CRLMs improves the long-term prognosis. On the other hand, patients with un-resectable CRLMs may benefit from chemotherapy alone or in addition to liver-directed therapies. The choice of the most appropriate therapeutic management of CRLMs depends mostly on the diagnostic imaging. Nowadays, multiple non-invasive imaging modalities are available and those have a pivotal role in the workup of patients with CRLMs. Although extensive research has been performed with regards to the diagnostic performance of ultrasonography, computed tomography, positron emission tomography and magnetic resonance for the detection of CRLMs, the optimal imaging strategies for staging and follow up are still to be established. This largely due to the progressive technological and pharmacological advances which are constantly improving the accuracy of each imaging modality. This review describes the non-invasive imaging approaches of CRLMs reporting the technical features, the clinical indications, the advantages and the potential limitations of each modality, as well as including some information on the development of new imaging modalities, the role of new contrast media and the feasibility of using parametric image analysis as diagnostic marker of presence of CRLMs.

  9. Non-invasive means of measuring hepatic fat content

    Institute of Scientific and Technical Information of China (English)

    Sanjeev R Mehta; E Louise Thomas; Jimmy D Bell; Desmond G Johnston; Simon D Taylor-Robinson

    2008-01-01

    Hepatic steatosis affects 20% to 30% of the general adult population in the western world. Currently, the technique of choice for determining hepatic fat deposition and the stage of fibrosis is liver biopsy. However, it is an invasive procedure and its use is limited, particularly in children. It may also be subject to sampling error. Non-invasive techniques such as ultrasound, computerised tomography (CT), magnetic resonance imaging (MRI) and proton magnetic resonance spectroscopy (1H MRS) can detect hepatic steatosis, but currently cannot distinguish between simple steatosis and steatohepatitis, or stage the degree of fibrosis accurately. Ultrasound is widely used to detect hepatic steatosis, but its sensitivity is reduced in the morbidly obese and also in those with small amounts of fatty infiltration. It has been used to grade hepatic fat content, but this is subjective. CT can detect hepatic steatosis, but exposes subjects to ionising radiation, thus limiting its use in longitudinal studies and in children. Recently, magnetic resonance (MR) techniques using chemical shift imaging have provided a quantitative assessment of the degree of hepatic fatty infiltration, which correlates well with liver biopsy results in the same patients. Similarly, in vivo 1H MRS is a fast, safe, non-invasive method for the quantification of intrahepatocellular lipid (IHCL) levels. Both techniques will be useful tools in future longitudinal clinical studies, either in examining the natural history of conditions causing hepatic steatosis(e.g. non-alcoholic fatty liver disease), or in testing new treatments for these conditions.

  10. Modulation of Untruthful Responses with Non-Invasive Brain Stimulation

    Science.gov (United States)

    Fecteau, Shirley; Boggio, Paulo; Fregni, Felipe; Pascual-Leone, Alvaro

    2013-01-01

    Deceptive abilities have long been studied in relation to personality traits. More recently, studies explored the neural substrates associated with deceptive skills suggesting a critical role of the prefrontal cortex. Here we investigated whether non-invasive brain stimulation over the dorsolateral prefrontal cortex (DLPFC) could modulate generation of untruthful responses about subject’s personal life across contexts (i.e., deceiving on guilt-free questions on daily activities; generating previously memorized lies about past experience; and producing spontaneous lies about past experience), as well as across modality responses (verbal and motor responses). Results reveal that real, but not sham, transcranial direct current stimulation (tDCS) over the DLPFC can reduce response latency for untruthful over truthful answers across contexts and modality responses. Also, contexts of lies seem to incur a different hemispheric laterality. These findings add up to previous studies demonstrating that it is possible to modulate some processes involved in generation of untruthful answers by applying non-invasive brain stimulation over the DLPFC and extend these findings by showing a differential hemispheric contribution of DLPFCs according to contexts. PMID:23550273

  11. Non-invasive quantification of brain tumor-induced astrogliosis

    Directory of Open Access Journals (Sweden)

    Baird Andrew

    2011-01-01

    Full Text Available Abstract Background CNS injury including stroke, infection, and tumor growth lead to astrogliosis, a process that involves upregulation of glial fibrillary acidic protein (GFAP in astrocytes. However, the kinetics of astrogliosis that is related to these insults (i.e. tumor is largely unknown. Results Using transgenic mice expressing firefly luciferase under the regulation of the GFAP promoter (GFAP-luc, we developed a model system to monitor astrogliosis upon tumor growth in a rapid, non-invasive manner. A biphasic induction of astrogliosis was observed in our xenograft model in which an early phase of activation of GFAP was associated with inflammatory response followed by a secondary, long-term upregulation of GFAP. These animals reveal GFAP activation with kinetics that is in parallel with tumor growth. Furthermore, a strong correlation between astrogliosis and tumor size was observed. Conclusions Our results suggest that non-invasive, quantitative bioluminescent imaging using GFAP-luc reporter animal is a useful tool to monitor temporal-spatial kinetics of host-mediated astrogliosis that is associated with glioma and metastatic brain tumor growth.

  12. Clinical role of non-invasive assessment of portal hypertension.

    Science.gov (United States)

    Bolognesi, Massimo; Di Pascoli, Marco; Sacerdoti, David

    2017-01-07

    Measurement of portal pressure is pivotal in the evaluation of patients with liver cirrhosis. The measurement of the hepatic venous pressure gradient represents the reference method by which portal pressure is estimated. However, it is an invasive procedure that requires significant hospital resources, including experienced staff, and is associated with considerable cost. Non-invasive methods that can be reliably used to estimate the presence and the degree of portal hypertension are urgently needed in clinical practice. Biochemical and morphological parameters have been proposed for this purpose, but have shown disappointing results overall. Splanchnic Doppler ultrasonography and the analysis of microbubble contrast agent kinetics with contrast-enhanced ultrasonography have shown better accuracy for the evaluation of patients with portal hypertension. A key advancement in the non-invasive evaluation of portal hypertension has been the introduction in clinical practice of methods able to measure stiffness in the liver, as well as stiffness/congestion in the spleen. According to the data published to date, it appears to be possible to rule out clinically significant portal hypertension in patients with cirrhosis (i.e., hepatic venous pressure gradient ≥ 10 mmHg) with a level of clinically-acceptable accuracy by combining measurements of liver stiffness and spleen stiffness along with Doppler ultrasound evaluation. It is probable that the combination of these methods may also allow for the identification of patients with the most serious degree of portal hypertension, and ongoing research is helping to ensure progress in this field.

  13. More accurate quantification of pulmonary blood flow by magnetic resonance imaging than by lung perfusion scintigraphy in patients with fontan circulation.

    Science.gov (United States)

    Fratz, Sohrab; Hess, John; Schwaiger, Markus; Martinoff, Stefan; Stern, Heiko C

    2002-09-17

    Quantitative evaluation of pulmonary perfusion using lung perfusion scintigraphy in patients with atriopulmonary anastomosis (APA) or total cavopulmonary connection (TCPC) or partial cavopulmonary connection (PCPC) is difficult because of preferential draining of the venae cavae to one lung. Scintigraphy is the gold standard. Phase-velocity MRI (PV-MRI) is a new technique for determining pulmonary perfusion. The aim of this study was therefore to determine whether PV-MRI is more accurate than scintigraphy for quantitative evaluation of pulmonary perfusion ratios in patients with APA, TCPC, or PCPC. We studied 15 patients with APA, TCPC, or PCPC (16+/-7 years old, 4 female). Twelve patients (15+/-8 years old, 3 female) with a single pulmonary blood source supplied by a subpulmonary ventricle, ensuring complete mixing of the radioactive tracer before entering the pulmonary circulation, served as controls. Pulmonary scintigraphy and PV-MRI were performed in all patients. Bland-Altman analysis showed a clinically unacceptable difference of 7.1% right pulmonary blood flow (27.2% upper and -13.0% lower limit of agreement) between the two methods in the study group. The two methods agreed excellently in the control group (difference, 1.6%; 4.0% upper and -7.2% lower limit of agreement), showing that the bad agreement in the study group was caused by the problems encountered using pulmonary scintigraphy in patients with APA, TCPC, or PCPC. Because of preferential caval flow into either lung, PV-MRI is more accurate for evaluating pulmonary perfusion ratios than lung perfusion scintigraphy in patients with Fontan-like circulation.

  14. [Pulmonary blood flow measurement using magnetic resonance imaging (MRI) without contrast medium;comparison of phase contrast MRI and perfusion-ventilation scintigraphy].

    Science.gov (United States)

    Yatsuyanagi, Eiji; Sato, Kazuhiro; Kikuchi, Keisuke; Saito, Hirotsugu

    2014-02-01

    To define the accuracy of pulmonary arterial blood flow (PA-flow) measured by phase contrast magnetic resonance imaging (PC-MRI), we compared the PA-flow data of PC-MRI with the data of perfusion-ventilation lung scintigraphy. Eighteen patients who preoperatively underwent PA-flow measurement using PC-MRI and perfusion-ventilation lung scintigraphy were evaluated. The PA-flow (cm3/sec) of MRI was calculated by multiplying maximum velocity (cm/sec) by region of interest (ROI) area (cm2) of measured main pulmonary artery using phase contrast method. The left to right ratio (R/L ratio) of PA-flow measured by PC-MRI was compared with the R/L ratios of the date of perfusion-ventilation lung scintigraphy. The R/L ratios of PC-MRI and perfusion lung scintigraphy were 1.43 ± 1.07 and 1.35 ± 0.82, respectively. Both ratios showed excellent correlation( y=-0.50+1.30x, r=0.99,pperfusion lung scintigraphy in the patients with a past history of lung resection, even if their R/L ratios of perfusion lung scintigraphy differed from those of ventilation lung scintigraphy. These results revealed that the PA-flow could be accurately measured by PC-MRI without contrast medium and nuclear medicine instruments.

  15. Modeling and optimization of Look-Locker spin labeling for measuring perfusion and transit time changes in activation studies taking into account arterial blood volume.

    Science.gov (United States)

    Francis, S T; Bowtell, R; Gowland, P A

    2008-02-01

    This work describes a new compartmental model with step-wise temporal analysis for a Look-Locker (LL)-flow-sensitive alternating inversion-recovery (FAIR) sequence, which combines the FAIR arterial spin labeling (ASL) scheme with a LL echo planar imaging (EPI) measurement, using a multireadout EPI sequence for simultaneous perfusion and T*(2) measurements. The new model highlights the importance of accounting for the transit time of blood through the arteriolar compartment, delta, in the quantification of perfusion. The signal expected is calculated in a step-wise manner to avoid discontinuities between different compartments. The optimal LL-FAIR pulse sequence timings for the measurement of perfusion with high signal-to-noise ratio (SNR), and high temporal resolution at 1.5, 3, and 7T are presented. LL-FAIR is shown to provide better SNR per unit time compared to standard FAIR. The sequence has been used experimentally for simultaneous monitoring of perfusion, transit time, and T*(2) changes in response to a visual stimulus in four subjects. It was found that perfusion increased by 83 +/- 4% on brain activation from a resting state value of 94 +/- 13 ml/100 g/min, while T*(2) increased by 3.5 +/- 0.5%. (c) 2008 Wiley-Liss, Inc.

  16. Effect of intranasally administered insulin on cerebral blood flow and perfusion

    DEFF Research Database (Denmark)

    Akintola, Abimbola A.; van Opstal, Anna M.; Westendorp, Rudi G.

    2017-01-01

    Insulin, a vasoactive modulator regulating peripheral and cerebral blood flow, has been consistently linked to aging and longevity. In this proof of principle study, using a randomized, double-blinded, placebo-controlled crossover design, we explored the effects of intranasally administered insulin...

  17. Cerebral blood perfusion in febrile convulsions with sup 123 -IMP SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Michihiro, Narumi; Ariizumi, Motomizu; Shiihara, Hiroaki; Suemitsu, Tomoko; Kurosawa, Yumiko; Egami, Yuriko (Dokkyo University Hospital, Saitama (Japan))

    1990-04-01

    Twenty-five pediatric patients with febrile convulsions underwent single photon emission computed tomography (SPECT) with N-isopropyl-p-(I-123) iodoamphetamine. Nineteen patients (76%) had a localized, decreased blood flow on early images, 12 of whom had it in the temporal region. According to seizure type, the abnormality was seen in 85% (17/20) for complex type, in contrast to 40% (2/5) for simple type. This finding has implications for pathological similarities between epilepsy and febrile convulsion. Delayed imaging performed on 12 patients showed redistribution in 5 of 9 patients having a decreased blood flow on early images. In the other 3 patients having normal findings on early images, however, different findings were seen on delayed images - normal, increased or decreased blood flow. There was no correlation between SPECT and encephalographic findings. A localized, decreased blood flow on SPECT seemed to reflect the risk for developing epilepsy. A follow-up care for preventing epilepsy is mandatory when there are abnormal findings on SPECT. (N.K.).

  18. Arterial pressure variations as parameters of brain perfusion in response to central blood volume depletion and repletion

    Directory of Open Access Journals (Sweden)

    Anne-Sophie G.T. Bronzwaer

    2014-04-01

    Full Text Available Rationale:A critical reduction in central blood volume (CBV is often characterized by hemodynamic instability. Restoration of a volume deficit may be established by goal-directed fluid therapy guided by respiration-related variation in systolic- and pulse pressure (SPV and PPV. Stroke volume index (SVI serves as a surrogate end-point of a fluid challenge but tissue perfusion itself has not been addressed. Objective: To delineate the relationship between arterial pressure variations, SVI and regional brain perfusion during CBV depletion and repletion in spontaneously breathing volunteers. Methods: This study quantified in 14 healthy subjects (11 male the effects of CBV depletion (by 30 and 70 degrees passive head-up tilt (HUT and a fluid challenge (by tilt back on CBV (thoracic admittance, mean middle cerebral artery (MCA blood flow velocity (Vmean, SVI, cardiac index (CI , PPV and SPV. Results: PPV (103±89%, p< 0.05 and SPV (136±117%, p< 0.05 increased with progression of central hypovolemia manifested by a reduction in thoracic admittance (11±5%, p< 0.001, SVI (28±6%, p< 0.001, CI (6±8%, p< 0.001 and MCAVmean (17±7%, p< 0.05 but not in arterial pressure. The reduction in MCAVmean correlated to the fall in SVI (R2=0.52, p< 0.0001 and inversely to PPV and SPV (R2=0.46 (p< 0.0001 and R2=0.45 (p< 0.0001, respectively. PPV and SPV predicted a ≥15% reduction in MCAVmean and SVI with comparable sensitivity (67%/ 67% vs. 63%/ 68% respectively and specificity (89%/94% vs. 89%/94%, respectively. A rapid fluid challenge by tilt-back restored all parameters to baseline values within one minute. Conclusion: In spontaneously breathing subjects, a reduction in MCAVmean was related to an increase in PPV and SPV during graded CBV depletion and repletion. Specifically, PPV and SPV predicted changes in both SVI and MCAVmean with comparable sensitivity and specificity, however the predictive value is limited in spontaneously breathing subjects.

  19. Thermal Imaging to Study Stress Non-invasively in Unrestrained Birds.

    Science.gov (United States)

    Jerem, Paul; Herborn, Katherine; McCafferty, Dominic; McKeegan, Dorothy; Nager, Ruedi

    2015-11-06

    Stress, a central concept in biology, describes a suite of emergency responses to challenges. Among other responses, stress leads to a change in blood flow that results in a net influx of blood to key organs and an increase in core temperature. This stress-induced hyperthermia is used to assess stress. However, measuring core temperature is invasive. As blood flow is redirected to the core, the periphery of the body can cool. This paper describes a protocol where peripheral body temperature is measured non-invasively in wild blue tits (Cyanistes caeruleus) using infrared thermography. In the field we created a set-up bringing the birds to an ideal position in front of the camera by using a baited box. The camera takes a short thermal video recording of the undisturbed bird before applying a mild stressor (closing the box and therefore capturing the bird), and the bird's response to being trapped is recorded. The bare skin of the eye-region is the warmest area in the image. This allows an automated extraction of the maximum eye-region temperature from each image frame, followed by further steps of manual data filtering removing the most common sources of errors (motion blur, blinking). This protocol provides a time series of eye-region temperature with a fine temporal resolution that allows us to study the dynamics of the stress response non-invasively. Further work needs to demonstrate the usefulness of the method to assess stress, for instance to investigate whether eye-region temperature response is proportional to the strength of the stressor. If this can be confirmed, it will provide a valuable alternative method of stress assessment in animals and will be useful to a wide range of researchers from ecologists, conservation biologists, physiologists to animal welfare researchers.

  20. Long-term pressure monitoring with arterial applanation tonometry: a non-invasive alternative during clinical intervention?

    Science.gov (United States)

    Matthys, Koen S; Kalmar, Alain F; Struys, Michel M R F; Mortier, Eric P; Avolio, Alberto P; Segers, Patrick; Verdonck, Pascal R

    2008-01-01

    Arterial tonometry is a non-invasive technique for continuous registration of arterial pressure waveforms. This study aims to assess tonometric blood pressure recording (TBP) as an alternative for invasive long-term bedside monitoring. A prospective study was set up where patients undergoing neurosurgical intervention were subjected to both invasive (IBP) and non-invasive (TBP) blood pressure monitoring during the entire procedure. A single-element tonometric pressure transducer was used to better investigate different inherent error sources of TBP measurement. A total of 5.7 hours of combined IBP and TBP were recorded from three patients. Although TBP performed fairly well as an alternative for IBP in steady state scenarios and some short-term variations, it could not detect relevant long-term pressure variations at all times. These findings are discussed in comparison to existing work. Physiological alterations at the site of TBP measurement are highlighted as a potentially important source of artifacts. It is concluded that at this point arterial tonometry remains not enough understood for long-term use during a delicate operative procedure. Physiological changes at the TBP measurement site deserve further investigation before tonometry technology is to be considered as an non-invasive alternative for long-term clinical monitoring.

  1. ABO typing in experimental cynomolgus monkeys using non-invasive methods

    Science.gov (United States)

    Wang, Xiaoxiao; Chen, Song; Chen, Gang

    2017-01-01

    ABH antigens are not expressed on the red blood cells of monkeys, making it difficult to accurately determine their blood type. In this study, we evaluated the feasibility, convenience, and stability of two non-invasive methods for ABO typing (a reverse gel system assay and a buccal mucosal cell immunofluorescent assay) in cynomolgus monkeys (n = 72). The renal tissue immunofluorescent assay was used to obtain an accurate blood type in the monkeys. Using the reverse gel system assay and preabsorbed serum, we achieved accurate detection of ABO blood groups in 65 of the 72 monkeys but obtained confusing results in the remaining 7. The original immunofluorescent staining of the buccal mucosal smears clearly and correctly identified the ABO blood groups in 50 of the 72 monkeys. After repeated smearing and staining, the ABO group type could be correctly identified in samples from the rest of the monkeys, which were either lacking sufficient buccal mucosal cells or contained impurities. Based on our findings, we recommend the reverse gel system assay as the first choice for primate blood type analysis, and the buccal mucosal cell immunofluorescent assay as a Supplementary Method whenever the reverse gel system assay fails to give a clear result. PMID:28112245

  2. In vivo non-invasive multiphoton tomography of human skin

    Science.gov (United States)

    König, Karsten; Riemann, Iris; Ehlers, Alexander; Le Harzic, Ronan

    2005-10-01

    High resolution non-invasive 3D imaging devices are required to detect pathogenic microorganisms such as Anthrax spores, bacteria, viruses, fungi and chemical agents entering biological tissues such as the epidermis. Due to the low light penetration depth and the biodamage potential, ultraviolet light sources can not be employed to realize intratissue imaging of bio- and chemohazards. We report on the novel near infrared laser technology multiphoton tomography and the high resolution 4D imaging tool DermaInspect for non-invasive detection of intratissue agents and their influence on cellular metabolism based on multiphoton autofluorescence imaging (MAI) and second harmonic generation (SHG). Femtosecond laser pulses in the spectral range of 750 nm to 850 nm have been used to image in vivo human skin with subcellular spatial and picosecond temporal resolution. The non-linear induced autofluorescence of both, skin tissues and microorganisms, originates mainly from naturally endogenous fluorophores/protein structures like NAD(P)H, flavins, keratin, collagen, elastin, porphyrins and melanin. Bacteria emit in the blue/green spectral range due to NAD(P)H and flavoproteins and, in certain cases, in the red spectral range due to the biosynthesis of Zn-porphyrins, coproporphyrin and protoporphyrin. Collagen and exogenous non-centrosymmetric molecules can be detected by SHG signals. The system DermaInspect consists of a wavelength-tunable compact 80/90 MHz Ti:sapphire laser, a scan module with galvo scan mirrors, piezo-driven objective, fast photon detector and time-resolved single photon counting unit. It can be used to perform optical sectioning and 3D autofluorescence lifetime imaging (τ-mapping) with 1 μm spatial resolution and 270 ps temporal resolution. The parameter fluorescence lifetime depends on the type of fluorophore and its microenvironment and can be used to distinguish bio- and chemohazards from cellular background and to gain information for pathogen

  3. Non-invasive measurement of pressure gradients using ultrasound

    DEFF Research Database (Denmark)

    Olesen, Jacob Bjerring; Traberg, Marie Sand; Pihl, Michael Johannes

    2013-01-01

    A non-invasive method for estimating 2-D pressure gradients from ultrasound vector velocity data is presented. The method relies on in-plane vector velocity fields acquired using the Transverse Oscillation method. The pressure gradients are estimated by applying the Navier-Stokes equations...... Medical 2202 UltraView Pro Focus scanner. The results are validated through finite element simulations of the carotid flow model where the geometry is determined from MR images. This proof of concept study was conducted at nine ultrasound frames per second. Estimated pressure gradients along...... the longitudinal direction of the constriction varied from 0 kPa/m to 10 kPa/m with a normalized bias of -9.1% for the axial component and -7.9% for the lateral component. The relative standard deviation of the estimator, given in reference to the peak gradient, was 28.4% in the axial direction and 64...

  4. Non-invasive brainstem monitoring: the ocular microtremor.

    Science.gov (United States)

    Robertson, James; Timmons, Shelly

    2007-10-01

    The ocular microtremor (OMT) is mediated by the oculomotor area of the brainstem and is altered in several pathologic states, including traumatic brain injury, general anesthesia, brain death, coma, Parkinsonism and multiple sclerosis. The EYETECT tremor monitor is a non-invasive means of measuring the frequency and amplitude of this microscopic tremor. It has been clinically tested in these clinical scenarios and has been found to be a reliable means of detecting the depth of anesthesia, and has been useful in predicting outcome in coma and traumatic brain injury patients and in confirming brain death. This paper reviews the scientific literature on the EYETECT OMT monitor, describes the underlying physiology and discusses the potential for future works and clinical use of this innovative technology.

  5. Neurophotonics: non-invasive optical techniques for monitoring brain functions

    Science.gov (United States)

    Torricelli, Alessandro; Contini, Davide; Mora, Alberto Dalla; Pifferi, Antonio; Re, Rebecca; Zucchelli, Lucia; Caffini, Matteo; Farina, Andrea; Spinelli, Lorenzo

    2014-01-01

    Summary The aim of this review is to present the state of the art of neurophotonics, a recently founded discipline lying at the interface between optics and neuroscience. While neurophotonics also includes invasive techniques for animal studies, in this review we focus only on the non-invasive methods that use near infrared light to probe functional activity in the brain, namely the fast optical signal, diffuse correlation spectroscopy, and functional near infrared spectroscopy methods. We also present an overview of the physical principles of light propagation in biological tissues, and of the main physiological sources of signal. Finally, we discuss the open issues in models, instrumentation, data analysis and clinical approaches. PMID:25764252

  6. Non-invasive exploration in an environmentally sensitive world

    Science.gov (United States)

    Livo, K.E.; Knepper, D.H.

    2004-01-01

    Modern remote sensing provides a means for locating and characterizing exposed mineralized systems in many parts of the world. These capabilities are non-invasive and help target specific areas for more detailed exploration. An example of how remote sensing technology can be used is evident from a study of the Questa Mining District, New Mexico. Analysis of low spectral resolution data from the Landsat Thematic Mapper satellite system clearly shows the regional distribution of two broad mineral groups often associated with mineralized systems: clay-carbonate-sulfate and iron oxides-iron hydroxides. Analysis of high spectral resolution data from the Airborne Visible and Infrared Imaging System (AVIRIS) shows the occurrence and distribution of many individual mineral species that characterize the pattern of hydrothermally altered rocks in the district.

  7. [Non-invasive brain stimulation for Parkinson's disease].

    Science.gov (United States)

    Gajo, Gianandrea; Pollak, Pierre; Lüscher, Christian; Benninger, David

    2015-04-29

    Parkinson's disease (PD) is a major socio-economic burden increasing with the aging population. In advanced PD, the emergence of symptoms refractory to conventional therapy poses a therapeutic challenge. The success of deep brain stimulation (DBS) and advances in the understanding of the pathophysiology of PD have raised interest in non-invasive brain stimulation (NIBS) as an alternative therapeutic tool. NIBS could offer an alternative approach for patients at risk who are excluded from surgery and/or to treat refractory symptoms. The treatment of the freezing of gait, a major cause of disability and falls in PD patients, could be enhanced by transcranial direct current stimulation (tDCS). A therapeutic study is currently performed at the Department of Neurology at the CHUV.

  8. Eyeblink conditioning: a non-invasive biomarker for neurodevelopmental disorders.

    Science.gov (United States)

    Reeb-Sutherland, Bethany C; Fox, Nathan A

    2015-02-01

    Eyeblink conditioning (EBC) is a classical conditioning paradigm typically used to study the underlying neural processes of learning and memory. EBC has a well-defined neural circuitry, is non-invasive, and can be employed in human infants shortly after birth making it an ideal tool to use in both developing and special populations. In addition, abnormalities in the cerebellum, a region of the brain highly involved in EBC, have been implicated in a number of neurodevelopmental disorders including autism spectrum disorders (ASDs). In the current paper, we review studies that have employed EBC as a biomarker for several neurodevelopmental disorders including fetal alcohol syndrome, Down syndrome, fragile X syndrome, attention deficit/hyperactivity disorder, dyslexia, specific language impairment, and schizophrenia. In addition, we discuss the benefits of using such a tool in individuals with ASD.

  9. Non-invasive beamforming add-on module

    KAUST Repository

    Bader, Ahmed

    2017-02-23

    An embodiment of a non-invasive beamforming add-on apparatus couples to an existing antenna port and rectifies the beam azimuth in the upstream and downstream directions. The apparatus comprises input circuitry that is configured to receive one or more signals from a neighboring node of the linear wireless sensor network; first amplifier circuitry configured to adjust an amplitude of a respective received signal in accordance with a weighting coefficient and invoke a desired phase to a carrier frequency of the received signal thereby forming a first amplified signal; and second amplifier circuitry configured to adjust a gain of the first amplified signal towards upstream and downstream neighbors of the linear wireless sensor in the linear wireless sensor network.

  10. Moral Enhancement Using Non-invasive Brain Stimulation

    Science.gov (United States)

    Darby, R. Ryan; Pascual-Leone, Alvaro

    2017-01-01

    Biomedical enhancement refers to the use of biomedical interventions to improve capacities beyond normal, rather than to treat deficiencies due to diseases. Enhancement can target physical or cognitive capacities, but also complex human behaviors such as morality. However, the complexity of normal moral behavior makes it unlikely that morality is a single capacity that can be deficient or enhanced. Instead, our central hypothesis will be that moral behavior results from multiple, interacting cognitive-affective networks in the brain. First, we will test this hypothesis by reviewing evidence for modulation of moral behavior using non-invasive brain stimulation. Next, we will discuss how this evidence affects ethical issues related to the use of moral enhancement. We end with the conclusion that while brain stimulation has the potential to alter moral behavior, such alteration is unlikely to improve moral behavior in all situations, and may even lead to less morally desirable behavior in some instances. PMID:28275345

  11. Physician liability and non-invasive prenatal testing.

    Science.gov (United States)

    Toews, Maeghan; Caulfield, Timothy

    2014-10-01

    Although non-invasive prenatal testing (NIPT) marks a notable development in the field of prenatal genetic testing, there are some physician liability considerations raised by this technology. As NIPT is still emerging as the standard of care and is just starting to receive provincial funding, the question arises of whether physicians are obligated to disclose the availability of NIPT to eligible patients as part of the physician-patient discussion about prenatal screening and diagnosis. If NIPT is discussed with patients, it is important to disclose the limitations of this technology with respect to its accuracy and the number of disorders that it can detect when compared with invasive diagnostic options. A failure to sufficiently disclose these limitations could leave patients with false assurances about the health of their fetuses and could raise informed consent and liability issues, particularly if a child is born with a disability as a result.

  12. Non-invasive assessment of phonatory and respiratory dynamics.

    Science.gov (United States)

    LaBlance, G R; Steckol, K F; Cooper, M H

    1991-10-01

    Evaluation of vocal pathology and the accompanying dysphonia should include an assessment of laryngeal structure and mobility as well as respiratory dynamics. Laryngeal structure is best observed through laryngoscopy which provides an accurate assessment of the tissues and their mobility. Respiratory measures of lung volume, air-flow and pressure, and breathing dynamics are typically determined via spirometry and pneumotachography. While the above are traditional invasive procedures which interfere with normal speech production, recent advances in electronic technology have resulted in the development of non-invasive procedures to assess phonatory and respiratory dynamics. These procedures, when used as an adjunct to laryngoscopy, can provide information that is useful in the diagnosis and management of vocal tract dysfunction. The Laryngograph and Computer-Aided Fluency Establishment Trainer, described here, are examples of this new technology.

  13. Non-Invasive in vivo Imaging in Small Animal Research

    Directory of Open Access Journals (Sweden)

    V. Koo

    2006-01-01

    Full Text Available Non-invasive real time in vivo molecular imaging in small animal models has become the essential bridge between in vitro data and their translation into clinical applications. The tremendous development and technological progress, such as tumour modelling, monitoring of tumour growth and detection of metastasis, has facilitated translational drug development. This has added to our knowledge on carcinogenesis. The modalities that are commonly used include Magnetic Resonance Imaging (MRI, Computed Tomography (CT, Positron Emission Tomography (PET, bioluminescence imaging, fluorescence imaging and multi-modality imaging systems. The ability to obtain multiple images longitudinally provides reliable information whilst reducing animal numbers. As yet there is no one modality that is ideal for all experimental studies. This review outlines the instrumentation available together with corresponding applications reported in the literature with particular emphasis on cancer research. Advantages and limitations to current imaging technology are discussed and the issues concerning small animal care during imaging are highlighted.

  14. Non invasive sensing technologies for cultural heritage management and fruition

    Science.gov (United States)

    Soldovieri, Francesco; Masini, Nicola

    2016-04-01

    The relevance of the information produced by science and technology for the knowledge of the cultural heritage depends on the quality of the feedback and, consequently, on the "cultural" distance between scientists and end-users. In particular, the solution to this problem mainly resides in the capability of end-users' capability to assess and transform the knowledge produced by diagnostics with regard to: information on both cultural objects and sites (decay patterns, vulnerability, presence of buried archaeological remains); decision making (management plan, conservation project, and excavation plan). From our experience in the field of the cultural heritage and namely the conservation, of monuments, there is a significant gap of information between technologists (geophysicists/physicists/engineers) and end-users (conservators/historians/architects). This cultural gap is due to the difficulty to interpret "indirect data" produced by non invasive diagnostics (i.e. radargrams/thermal images/seismic tomography etc..) in order to provide information useful to improve the historical knowledge (e.g. the chronology of the different phases of a building), to characterise the state of conservation (e.g. detection of cracks in the masonry) and to monitor in time cultural heritage artifacts and sites. The possible answer to this difficulty is in the set-up of a knowledge chain regarding the following steps: - Integrated application of novel and robust data processing methods; - Augmented reality as a tool for making easier the interpretation of non invasive - investigations for the analysis of decay pathologies of masonry and architectural surfaces; - The comparison between direct data (carrots, visual inspection) and results from non-invasive tests, including geophysics, aims to improve the interpretation and the rendering of the monuments and even of the archaeological landscapes; - The use of specimens or test beds for the detection of archaeological features and

  15. Non-invasive brain stimulation in neglect rehabilitation: An update.

    Directory of Open Access Journals (Sweden)

    René Martin Müri

    2013-06-01

    Full Text Available Here, we review the effects of non-invasive brain stimulation (NIBS such as transcranial magnetic stimulation (TMS or transcranial direct current stimulation (tDCS in the rehabilitation of neglect. We found 12 studies including 172 patients (10 TMS studies and 2 tDCS studies fulfilling our search criteria. Activity of daily living (ADL measures such as the Barthel Index or more specifically for neglect, the Catherine Bergego Scale were the outcome measure in 3 studies. Five studies were randomized controlled trials with a follow-up time after intervention of up to 6 weeks. One TMS study fulfilled criteria for Class I and one for Class III evidence.The studies are heterogeneous concerning their methodology, outcome measures, and stimulation parameters making firm comparisons and conclusions difficult. Overall, there are however promising results for theta burst stimulation, suggesting that TMS is a powerful add-on therapy in the rehabilitation of neglect patients.

  16. Non-invasive brain stimulation in neglect rehabilitation: an update.

    Science.gov (United States)

    Müri, René Martin; Cazzoli, Dario; Nef, Tobias; Mosimann, Urs P; Hopfner, Simone; Nyffeler, Thomas

    2013-01-01

    Here, we review the effects of non-invasive brain stimulation such as transcranial magnetic stimulation (TMS) or transcranial direct current stimulation (tDCS) in the rehabilitation of neglect. We found 12 studies including 172 patients (10 TMS studies and 2 tDCS studies) fulfilling our search criteria. Activity of daily living measures such as the Barthel Index or, more specifically for neglect, the Catherine Bergego Scale were the outcome measure in three studies. Five studies were randomized controlled trials with a follow-up time after intervention of up to 6 weeks. One TMS study fulfilled criteria for Class I and one for Class III evidence. The studies are heterogeneous concerning their methodology, outcome measures, and stimulation parameters making firm comparisons and conclusions difficult. Overall, there are however promising results for theta-burst stimulation, suggesting that TMS is a powerful add-on therapy in the rehabilitation of neglect patients.

  17. TIPS bilateral noise reduction in 4D CT perfusion scans produces high-quality cerebral blood flow maps

    NARCIS (Netherlands)

    Mendrik, A.M.; Vonken, E.J.; Ginneken, B. van; Jong, H.W. de; Riordan, A.; Seeters, T. van; Smit, E.J.; Viergever, M.A.; Prokop, M.

    2011-01-01

    Cerebral computed tomography perfusion (CTP) scans are acquired to detect areas of abnormal perfusion in patients with cerebrovascular diseases. These 4D CTP scans consist of multiple sequential 3D CT scans over time. Therefore, to reduce radiation exposure to the patient, the amount of x-ray radiat

  18. TIPS bilateral noise reduction in 4D CT perfusion scans produces high-quality cerebral blood flow maps

    NARCIS (Netherlands)

    A. Mendrik (Adrienne); E.J.P.A. Vonken; B.T.J. van Ginneken (Berbke); J.R. Riordan (John ); H.W.A.M. de Jong (Hugo); T. van Seeters (Tom); E.J. Smit (Ewoud); M.A. Viergever (Max); M. Prokop (Mathias)

    2011-01-01

    textabstractCerebral computed tomography perfusion (CTP) scans are acquired to detect areas of abnormal perfusion in patients with cerebrovascular diseases. These 4D CTP scans consist of multiple sequential 3D CT scans over time. Therefore, to reduce radiation exposure to the patient, the amount of

  19. Technetium-99m d,l-HM-PAO: a new radiopharmaceutical for SPECT imaging of regional cerebral blood perfusion

    Energy Technology Data Exchange (ETDEWEB)

    Neirinckx, R.D.; Canning, L.R.; Piper, I.M.; Nowotnik, D.P.; Pickett, R.D.; Holmes, R.A.; Volkert, W.A.; Forster, A.M.; Weisner, P.S.; Marriott, J.A.

    1987-02-01

    Following investigation of a large number of new ligands based upon propylene amine oxime (PnAO) the d,l-diastereoisomer of hexamethyl propyleneamine oxime (HM-PAO) was selected as the preferred ligand for 99mTc as a tracer for cerebral perfusion imaging. The neutral, lipophilic 99mTc complex of d,l-HM-PAO was formed in high yield by stannous reduction of 99Mo/99mTc generator eluate using a kit formulation of the ligand. Two minutes following i.v. administration of this complex in rats, 2.25% of the injected dose appears in the brain. Little washout of the tracer is observed up to 24 hr postinjection. By qualitative autoradiographic comparison with iodoantipyrine this new radiopharmaceutical displays blood flow dependent brain uptake with little redistribution of the tracer over time. The lipophilic 99mTc complex converts slowly in vitro to a secondary complex. This conversion process may account for the ability of (99mTc)d,l-HM-PAO to be retained within the brain without redistribution.

  20. Influence of vascular enhancement, age and gender on pulmonary perfused blood volume quantified by dual-energy-CTPA

    Energy Technology Data Exchange (ETDEWEB)

    Meinel, Felix G., E-mail: felix.meinel@med.uni-muenchen.de; Graef, Anita, E-mail: anita.graef@med.uni-muenchen.de; Sommer, Wieland H., E-mail: wieland.sommer@uni-muenchen.de; Thierfelder, Kolja M., E-mail: kolja.thierfelder@uni-muenchen.de; Reiser, Maximilian F., E-mail: maximilian.reiser@med.uni-muenchen.de; Johnson, Thorsten R.C., E-mail: thorsten.johnson@med.uni-muenchen.de

    2013-09-15

    Objectives: To determine the influence of technical and demographic parameters on quantification of pulmonary perfused blood volume (PBV) in dual energy computed tomography pulmonary angiography (DE-CTPA). Materials and methods: Pulmonary PBV was quantified in 142 patients who underwent DE-CTPA for suspected pulmonary embolism but in whom no thoracic pathologies were detected. Multivariate linear regression analysis was performed to calculate the influence of age, gender, enhancement of pulmonary trunk and enhancement difference between pulmonary trunk and left atrium (as a measure of timing) on PBV values. The resulting regression coefficients were used to calculate age-specific ranges of normal for PBV values adjusted for vascular enhancement and timing. Results: Enhancement of the pulmonary trunk (β = −0.29, p = 0.001) and enhancement difference between pulmonary trunk and left atrium (β = −0.24, p = 0.003) were found to significantly influence PBV values. Age (β = −0.33, p < 0.001) but not gender (β = 0.14, p = 0.05) had a significant negative influence on pulmonary PBV values. There was a 20% relative decrease of pulmonary PBV from patients aged <30 to patients over 80 years of age. Conclusions: DE-CTPA derived PBV values need to be corrected for age, vascular enhancement and timing but not for gender. The age-specific ranges of normal derived from this study can be used as a reference in future studies of PBV in pulmonary pathologies.

  1. Increased blood-brain barrier permeability on perfusion computed tomography predicts hemorrhagic transformation in acute ischemic stroke.

    Science.gov (United States)

    Ozkul-Wermester, Ozlem; Guegan-Massardier, Evelyne; Triquenot, Aude; Borden, Alaina; Perot, Guillaume; Gérardin, Emmanuel

    2014-01-01

    Perfusion computed tomography (CT) is capable of measuring the permeability surface product (PS). PS reflects the permeability of the blood-brain barrier, involved in the pathophysiology of hemorrhagic transformation (HT) of ischemic stroke. The aim of our study was to determine if an increased PS can predict HT. A total of 86 patients with ischemic stroke were included. They underwent multimodality CT, including the measurement of PS. We compared the clinical and radiological characteristics of patients who developed HT to those who did not, using univariate analysis. Multivariate regression analyses were then used to determine HT predictors. HT was observed in 27 patients (31%). Infarct PS was significantly associated with HT (p = 0.047), as were atrial fibrillation (p = 0.03), admission National Institute of Health Stroke Scale score (p = 0.02), infarct volume (p = 0.0004), presence of large-vessel occlusion (p = 0.0005) and a poorer collateral status (p = 0.003). Using logistic regression modeling, an infarct PS >0.84 ml/100 g/min was an independent predictor of HT (OR 28, 95% CI 1.75-452.98; p = 0.02). Other independent predictors of HT were infarct volume and a history of atrial fibrillation. Our findings suggest that infarct PS can be a predictor of HT and may help clinicians to improve patient care around thrombolysis decisions in the acute phase of ischemic stroke. © 2014 S. Karger AG, Basel.

  2. Novel non invasive diagnostic strategies in bladder cancer.

    Science.gov (United States)

    Truta, Anamaria; Popon, Tudor Adrian Hodor; Saraci, George; Ghervan, Liviu; Pop, Ioan Victor

    2016-01-01

    Bladder cancer is one of the most commonly diagnosed malignancies worldwide, derived from the urothelium of the urinary bladder and defined by long asymptomatic and atypical clinical picture. Its complex etiopathogenesis is dependent on numerous risk factors that can be divided into three distinct categories: genetic and molecular abnormalities, chemical or environmental exposure and previous genitourinary disorders and family history of different malignancies. Various genetic polymorphisms and microRNA might represent useful diagnostic or prognostic biomarkers. Genetic and molecular abnormalities - risk factors are represented by miRNA or genetic polymorphisms proved to be part of bladder carcinogenesis such as: genetic mutations of oncogenes TP53, Ras, Rb1 or p21 oncoproteins, cyclin D or genetic polymorhisms of XPD,ERCC1, CYP1B1, NQO1C609T, MDM2SNP309, CHEK2, ERCC6, NRF2, NQO1Pro187Ser polymorphism and microRNA (miR-143, -145, -222, -210, -10b, 576-3p). The aim of our article is to highlight the most recent acquisitions via molecular biomarkers (miRNAs and genetic polymorphisms) involved in bladder cancer in order to provide early diagnosis, precise therapy according to the molecular profile of bladder tumors, as well as to improve clinical outcome, survival rates and life quality of oncological patients. These molecular biomarkers play a key role in bladder carcinogenesis, clinical evolution, prognosis and therapeutic response and explain the molecular mechanisms involved in bladder carcinogenesis; they can also be selected as therapeutic targets in developing novel therapeutic strategies in bladder malignancies. Moreover, the purpose in defining these molecular non invasive biomarkers is also to develop non invasive screening programs in bladder malignancies with the result of decreasing bladder cancer incidence in risk population.

  3. Non-invasive actionable biomarkers for metastatic prostate cancer

    Directory of Open Access Journals (Sweden)

    Jun Luo

    2016-10-01

    Full Text Available In the current clinical setting, many disease management options are available for men diagnosed with prostate cancer. For metastatic prostate cancer, first-line therapies almost always involve agents designed to inhibit androgen receptor (AR signaling. Castration-resistant prostate cancers (CRPCs that arise following first-line androgen deprivation therapies (ADT may continue to respond to additional lines of AR-targeting therapies (abiraterone and enzalutamide, chemotherapies (docetaxel and cabazitaxel, bone-targeting Radium-223 therapy, and immunotherapy sipuleucel-T. The rapidly expanding therapies for CRPC is expected to transform this lethal disease into one that can be managed for prolonged period of time. In the past 3 years, a number of promising biomarkers that may help to guide treatment decisions have been proposed and evaluated, including androgen receptor splice variant-7 (AR-V7, a truncated AR lacking the ligand-binding domain (LBD and mediate constitutively-active AR signaling. Putative treatment selection markers such as AR-V7 may further improve survival benefit of existing therapies and help to accelerate development of new agents for metastatic prostate cancer. In the metastatic setting, it is important to consider compatibility between the putative biomarker with non-invasive sampling. In this review, biomarkers relevant to the setting of metastatic prostate cancer are discussed with respect to a number of key attributes critical for clinical development of non-invasive, actionable markers. It is envisioned that biomarkers for metastatic prostate cancer will continue to be discovered, developed, and refined to meet the unmet needs in both standard-of-care and clinical trial settings.

  4. Costs and clinical outcomes for non-invasive versus invasive diagnostic approaches to patients with suspected in-stent restenosis.

    Science.gov (United States)

    Min, James K; Hasegawa, James T; Machacz, Susanne F; O'Day, Ken

    2016-02-01

    This study compared costs and clinical outcomes of invasive versus non-invasive diagnostic evaluations for patients with suspected in-stent restenosis (ISR) after percutaneous coronary intervention. We developed a decision model to compare 2 year diagnosis-related costs for patients who presented with suspected ISR and were evaluated by: (1) invasive coronary angiography (ICA); (2) non-invasive stress testing strategy of myocardial perfusion imaging (MPI) with referral to ICA based on MPI; (3) coronary CT angiography-based testing strategy with referral to ICA based on CCTA. Costs were modeled from the payer's perspective using 2014 Medicare rates. 56 % of patients underwent follow-up diagnostic testing over 2 years. Compared to ICA, MPI (98.6 %) and CCTA (98.1 %) exhibited lower rates of correct diagnoses. Non-invasive strategies were associated with reduced referrals to ICA and costs compared to an ICA-based strategy, with diagnostic costs lower for CCTA than MPI. Overall 2-year costs were highest for ICA for both metallic as well as BVS stents ($1656 and $1656, respectively) when compared to MPI ($1444 and $1411) and CCTA. CCTA costs differed based upon stent size and type, and were highest for metallic stents >3.0 mm followed by metallic stents 3.0 mm ($1466 vs. $1242 vs. $855 vs. $490, respectively). MPI for suspected ISR results in lower costs and rates of complications than invasive strategies using ICA while maintaining high diagnostic performance. Depending upon stent size and type, CCTA results in lower costs than MPI.

  5. Non-invasive cardiac imaging techniques and vascular tools for the assessment of cardiovascular disease in type 2 diabetes mellitus.

    Science.gov (United States)

    Djaberi, R; Beishuizen, E D; Pereira, A M; Rabelink, T J; Smit, J W; Tamsma, J T; Huisman, M V; Jukema, J W

    2008-09-01

    Cardiovascular disease is the major cause of mortality in type 2 diabetes mellitus. The criteria for the selection of those asymptomatic patients with type 2 diabetes who should undergo cardiac screening and the therapeutic consequences of screening remain controversial. Non-invasive techniques as markers of atherosclerosis and myocardial ischaemia may aid risk stratification and the implementation of tailored therapy for the patient with type 2 diabetes. In the present article we review the literature on the implementation of non-invasive vascular tools and cardiac imaging techniques in this patient group. The value of these techniques as endpoints in clinical trials and as risk estimators in asymptomatic diabetic patients is discussed. Carotid intima-media thickness, arterial stiffness and flow-mediated dilation are abnormal long before the onset of type 2 diabetes. These vascular tools are therefore most likely to be useful for the identification of 'at risk' patients during the early stages of atherosclerotic disease. The additional value of these tools in risk stratification and tailored therapy in type 2 diabetes remains to be proven. Cardiac imaging techniques are more justified in individuals with a strong clinical suspicion of advanced coronary heart disease (CHD). Asymptomatic myocardial ischaemia can be detected by stress echocardiography and myocardial perfusion imaging. The more recently developed non-invasive multi-slice computed tomography angiography is recommended for exclusion of CHD, and can therefore be used to screen asymptomatic patients with type 2 diabetes, but has the associated disadvantages of high radiation exposure and costs. Therefore, we propose an algorithm for the screening of asymptomatic diabetic patients, the first step of which consists of coronary artery calcium score assessment and exercise ECG.

  6. Neurosonological examination: A non-invasive approach for the detection of cerebrovascular impairment in AD

    Directory of Open Access Journals (Sweden)

    Barbora eUrbanova

    2014-01-01

    Full Text Available There has been a growing interest in vascular impairment associated with Alzheimer’s disease (AD. This interest was stimulated by the findings of higher incidence of vascular risk factors in AD. Signs of vascular impairment were investigated notably in the field of imaging methods. Our aim was to explore ultrasonographic studies of extra- and intracranial vessels in patients with AD and mild cognitive impairment (MCI and define implications for diagnosis, treatment and prevention of the disease. The most frequently studied parameters with extracranial ultrasound are intima-media thickness in common carotid artery, carotid atherosclerosis, and total cerebral blood flow. The transcranial ultrasound concentrates mostly on flow velocities, pulsatility indices, cerebrovascular reserve capacity, cerebral microembolization. Studies suggest there is morphological and functional impairment of cerebral circulation in AD compared to healthy subjects. Ultrasound as a non-invasive method could be potentially useful in identifying individuals in a higher risk of progression of cognitive decline.

  7. Characterization of hepatocellular carcinoma (HCC) lesions using a novel CT-based volume perfusion (VPCT) technique

    Energy Technology Data Exchange (ETDEWEB)

    Kaufmann, S., E-mail: sascha.kaufmann@med.uni-tuebingen.de [Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University, Hoppe-Seyler-Strasse 3, 72076 Tübingen (Germany); Horger, T., E-mail: horger@ma.tum.de [Technische Universität München, Boltzmannstraße 3, 85748 Garching (Germany); Oelker, A., E-mail: oelker@ma.tum.de [Technische Universität München, Boltzmannstraße 3, 85748 Garching (Germany); Kloth, C., E-mail: christopher.kloth@med.uni-tuebingen.de [Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University, Hoppe-Seyler-Strasse 3, 72076 Tübingen (Germany); Nikolaou, K., E-mail: Konstantin.Nikolaou@med.uni-tuebingen.de [Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University, Hoppe-Seyler-Strasse 3, 72076 Tübingen (Germany); Schulze, M., E-mail: maximilian.schulze@med.uni-tuebingen.de [Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University, Hoppe-Seyler-Strasse 3, 72076 Tübingen (Germany); Horger, M., E-mail: marius.horger@med.uni-tuebingen.de [Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University, Hoppe-Seyler-Strasse 3, 72076 Tübingen (Germany)

    2015-06-15

    Highlights: • Quantification of perfusion with VPCT has great potential for functional imaging. • We present our preliminary results of perfusion parameters (Blood Flow, Blood Volume and kk-trans) of hepatocellular carcinoma (HCC) in terms of using VPCT and two different calculation methods, compare their results and look for correlation between tumor arterialization and lesion size. • VPCT can measure tumor volume perfusion non-invasively and enables quantification of the degree of HCC arterialization. Results are dependent on the technique used with best inter-method correlation for Blood Flow. • Tumor arterialization did not proved size-dependent. - Abstract: Objective: To characterize hepatocellular carcinoma (HCC) in terms of perfusion parameters using volume perfusion CT (VPCT) and two different calculation methods, compare their results, look for interobserver agreement of measurements and correlation between tumor arterialization and lesion size. Material and methods: This study was part of a prospective monitoring study in patients with HCC undergoing TACE, which was approved by the local Institutional Review Board. 79 HCC-patients (mean age, 64.7) with liver cirrhosis were enrolled. VPCT was performed for 40 s covering the involved liver (80 kV, 100/120 mAs) using 64 mm × 0.6 mm collimation, 26 consecutive volume measurements, 50 mL iodinated contrast IV and 5 mL/s flow rate. Mean/maximum blood flow (BF; ml/100 mL/min), blood volume (BV) and k-trans were determined both with the maximum slope + Patlak vs. deconvolution method. Additionally, the portal venous liver perfusion (PVP), the arterial liver perfusion (ALP) and the hepatic perfusion index (HPI) were determined for each tumor including size measurements. Interobserver agreement for all perfusion parameters was calculated using intraclass correlation coefficients (ICC). Results: The max. slope + Patlak method yielded: BFmean/max = 37.8/57 mL/100 g-tissue/′, BVmean/max = 9.8/11.1 mL/100 g

  8. Hydrogel-based electrochemical sensor for non-invasive and continuous glucose monitoring

    Science.gov (United States)

    Park, Habeen; Lee, Ji-Young; Kim, Dong-Chul; Koh, Younggook; Cha, Junhoe

    2017-07-01

    Monitoring blood glucose level of diabetic patients is crucial in diabetes care from life threating complications. Selfmonitoring blood glucose (SMBG) that involves finger prick to draw blood samples into the measurement system is a widely-used method of routine measurement of blood glucose levels to date. SMBG includes, however, unavoidable pain problems resulting from the repetitive measurements. We hereby present a hydrogel-based electrochemical (H-EC) sensor to monitor the glucose level, non-invasively. Glucose oxidase (GOx) was immobilized in the disc-type hydroxyethyl methacrylate (HEMA) based hydrogel and kept intact in the hydrogel. Fast electron transfer mediated by Prussian blue (PB, hexacyanoferrate) generated efficient signal amplifications to facilitate the detection of the extracted glucose from the interstitial fluid. The linear response and the selectivity against glucose of the H-EC sensor were validated by chronoamperometry. For the practical use, the outcomes from the correlation of the extracted glucose concentration and the blood glucose value by on-body extraction, as well as the validation of the hydrogel-based electrochemical (H-EC) device, were applied to the on-body glucose monitoring.

  9. Ex vivo non-invasive assessment of cell viability and proliferation in bio-engineered whole organ constructs.

    Science.gov (United States)

    Ren, Xi; Tapias, Luis F; Jank, Bernhard J; Mathisen, Douglas J; Lanuti, Michael; Ott, Harald C

    2015-06-01

    Decellularized organ scaffolds allow whole organ regeneration and study of cell behavior in three-dimensional culture conditions. Cell viability within the bio-engineered organ constructs is an essential parameter reflecting the performance of participating cells during long-term ex vivo culture, and is a prerequisite for further functional performance. Resazurin-based redox metabolic assays have been used to monitor cell viability in both two- and three-dimensional cell cultures. Here we developed a method for monitoring cell viability and proliferation in bio-engineered organ constructs using a resazurin perfusion assay. This method allows non-invasive, repetitive and rapid estimation of viable cell numbers during long-term ex vivo culture. As a proof-of-principle, we assessed the performance of two different endothelial sources and the impact of different perfusion programs on endothelial viability after re-endothelialization of decellularized lung scaffolds. The resazurin-based perfusion assay revealed changes in endothelial viability and proliferation during long-term ex vivo culture, which was consistent with histological assessment at different time points. Finally, we showed that this method could be used for assessment of proliferation and cytotoxicity after pharmacological treatment on a three-dimensional non-small cell lung cancer culture model.

  10. Selective microvascular muscle perfusion imaging in the shoulder with intravoxel incoherent motion (IVIM).

    Science.gov (United States)

    Nguyen, Audrey; Ledoux, Jean-Baptiste; Omoumi, Patrick; Becce, Fabio; Forget, Joachim; Federau, Christian

    2017-01-01

    The evaluation of local muscle recruitment during a specific movement can be done indirectly by measuring changes in local blood flow. Intravoxel incoherent motion perfusion imaging exploits some properties of the magnetic resonance to measure locally microvascular perfusion, and seems ideally suited for this task. We studied the selectivity of the increase in intravoxel incoherent motion blood flow related parameter fD* in the muscles of 24 shoulders after two physical exam maneuvers, Jobe and Lift-off test (test order reversed in half of the volunteers) each held 2min against resistance. After a lift-off, IVIM blood flow-related fD* was increased in the subscapularis (in 10(-3)mm(2)s(-1), 3.24±0.86 vs. rest 1.37±0.58, pmuscles and deltoid bundles respectively. After a Jobe test, increase in fD* was scattered within the rotator cuff muscles, but was selective for the lateral deltoid compared to the other deltoid bundles (anterior, pmuscle testing of the shoulder muscles with IVIM. This technique has the potential to non-invasively characterize perfusion-related musculoskeletal physiological as well as pathological processes. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Non-Invasive Measurement of Adrenocortical Activity in Blue-Fronted Parrots (Amazona aestiva, Linnaeus, 1758.

    Directory of Open Access Journals (Sweden)

    João C P Ferreira

    Full Text Available Parrots kept in zoos and private households often develop psychological and behavioural disorders. Despite knowing that such disorders have a multifactorial aetiology and that chronic stress is involved, little is known about their development mainly due to a poor understanding of the parrots' physiology and the lack of validated methods to measure stress in these species. In birds, blood corticosterone concentrations provide information about adrenocortical activity. However, blood sampling techniques are difficult, highly invasive and inappropriate to investigate stressful situations and welfare conditions. Thus, a non-invasive method to measure steroid hormones is critically needed. Aiming to perform a physiological validation of a cortisone enzyme immunoassay (EIA to measure glucocorticoid metabolites (GCM in droppings of 24 Blue-fronted parrots (Amazona aestiva, two experiments were designed. During the experiments all droppings were collected at 3-h intervals. Initially, birds were sampled for 24 h (experiment 1 and one week later assigned to four different treatments (experiment 2: Control (undisturbed, Saline (0.2 mL of 0.9% NaCl IM, Dexamethasone (1 mg/kg IM and Adrenocorticotropic hormone (ACTH; 25 IU IM. Treatments (always one week apart were applied to all animals in a cross-over study design. A daily rhythm pattern in GCM excretion was detected but there were no sex differences (first experiment. Saline and dexamethasone treatments had no effect on GCM (not different from control concentrations. Following ACTH injection, GCM concentration increased about 13.1-fold (median at the peak (after 3-9 h, and then dropped to pre-treatment concentrations. By a successful physiological validation, we demonstrated the suitability of the cortisone EIA to non-invasively monitor increased adrenocortical activity, and thus, stress in the Blue-fronted parrot. This method opens up new perspectives for investigating the connection between behavioural

  12. Continuous Non-Invasive Arterial Pressure Technique Improves Patient Monitoring during Interventional Endoscopy

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    Sylvia Siebig, Felix Rockmann, Karl Sabel, Ina Zuber-Jerger, Christine Dierkes, Tanja Brünnler, Christian E. Wrede

    2009-01-01

    Full Text Available Introduction: Close monitoring of arterial blood pressure (BP is a central part of cardiovascular surveillance of patients at risk for hypotension. Therefore, patients undergoing diagnostic and therapeutic procedures with the use of sedating agents are monitored by discontinuous non-invasive BP measurement (NIBP. Continuous non-invasive BP monitoring based on vascular unloading technique (CNAP®, CN Systems, Graz may improve patient safety in those settings. We investigated if this new technique improved monitoring of patients undergoing interventional endoscopy. Methods: 40 patients undergoing interventional endoscopy between April and December 2007 were prospectively studied with CNAP® in addition to standard monitoring (NIBP, ECG and oxygen saturation. All monitoring values were extracted from the surveillance network at one-second intervals, and clinical parameters were documented. The variance of CNAP® values were calculated for every interval between two NIBP measurements. Results: 2660 minutes of monitoring were recorded (mean 60.1±34.4 min/patient. All patients were analgosedated with midazolam and pethidine, and 24/40 had propofol infusion (mean 90.9±70.3 mg. The mean arterial pressure for CNAP® was 102.4±21.2 mmHg and 106.8±24.8 mmHg for NIBP. Based on the first NIBP value in an interval between two NIBP measurements, BP values determined by CNAP® showed a maximum increase of 30.8±21.7% and a maximum decrease of 22.4±28.3% (mean of all intervals. Discussion: Conventional intermittent blood pressure monitoring of patients receiving sedating agents failed to detect fast changes in BP. The new technique CNAP® improved the detection of rapid BP changes, and may contribute to a better patient safety for those undergoing interventional procedures.

  13. Corrections of arterial input function for dynamic H215O PET to assess perfusion of pelvic tumours: arterial blood sampling versus image extraction

    Science.gov (United States)

    Lüdemann, L.; Sreenivasa, G.; Michel, R.; Rosner, C.; Plotkin, M.; Felix, R.; Wust, P.; Amthauer, H.

    2006-06-01

    Assessment of perfusion with 15O-labelled water (H215O) requires measurement of the arterial input function (AIF). The arterial time activity curve (TAC) measured using the peripheral sampling scheme requires corrections for delay and dispersion. In this study, parametrizations with and without arterial spillover correction for fitting of the tissue curve are evaluated. Additionally, a completely noninvasive method for generation of the AIF from a dynamic positron emission tomography (PET) acquisition is applied to assess perfusion of pelvic tumours. This method uses a volume of interest (VOI) to extract the TAC from the femoral artery. The VOI TAC is corrected for spillover using a separate tissue TAC and for recovery by determining the recovery coefficient on a coregistered CT data set. The techniques were applied in five patients with pelvic tumours who underwent a total of 11 examinations. Delay and dispersion correction of the blood TAC without arterial spillover correction yielded in seven examinations solutions inconsistent with physiology. Correction of arterial spillover increased the fitting accuracy and yielded consistent results in all patients. Generation of an AIF from PET image data was investigated as an alternative to arterial blood sampling and was shown to have an intrinsic potential to determine the AIF noninvasively and reproducibly. The AIF extracted from a VOI in a dynamic PET scan was similar in shape to the blood AIF but yielded significantly higher tissue perfusion values (mean of 104.0 ± 52.0%) and lower partition coefficients (-31.6 ± 24.2%). The perfusion values and partition coefficients determined with the VOI technique have to be corrected in order to compare the results with those of studies using a blood AIF.

  14. The evolution of the cerebral blood volume abnormality in patients with ischemic stroke: a CT perfusion study

    Energy Technology Data Exchange (ETDEWEB)

    D' Esterre, Christopher D.; Lee, Ting Yim (Lawson Health Research Inst., London (Canada); Robarts Research Inst., London (Canada)), email: tlee@robarts.ca; Aviv, Richard I. (Sunnybrook Health Sciences Centre, Toronto (Canada))

    2012-05-15

    Background: Accurate identification of the acute infarct core abnormality is important for guiding acute stroke treatment. Abnormality volumes from diffusion-weighted MRI (DWI) and CT perfusion (CTP)-cerebral blood volume (CBV) are highly correlated. DWI lesions have been shown to be reversible at 24 h. Purpose: To examine the temporal profile of the CT perfusion (CTP)-derived CBV abnormality out to 7 days post ischemic stroke. Material and Methods: Twenty-six patients were included. Group A (n = 13) underwent a noncontrast CT (NCCT), CTP/CT angiography (CTA) within 6 h of stroke onset, CTP/CTA at 24 h, and CTP/NCCT at 5-7 days post stroke. Group B (n = 13) underwent a NCCT, CTP/CTA within 6 h of stroke onset, and NCCT at 5-7 days. Recanalization status was established in all patients. For both groups, infarct volumes were traced on 5-7 day NCCT images and superimposed onto all CTP-CBV functional maps to determine CBV. Group B (n = 13) admission images were used to define CBV infarct thresholds for gray and white matter. CBV-lesion overestimation was determined for Group A using the thresholds from Group B. Results: CBV (ml x 100g- 1; mean +- stdev) for gray/white matter, within confirmed infarcted regions (CBVI) at admission, 24 h, and 5-7 days were 1.82 +- 0.56, 1.56 +- 0.42, 1.75 +- 0.31, and 1.38 +- 0.65, 1.13 +- 0.31, 1.32 +- 0.44, respectively, when averaged over all patients (P > 0.05). Four patients had tissue time-density curves from ischemic lesions (TDCi) with an incomplete contrast medium wash-out phase (truncation) at admission and/or 24 h. Compared to admission, gray matter CBVI was higher at 5-7 days for patients with TDCi truncation (P < 0.05). There were no significant CBVI increases for the eight patients without truncation (P > 0.05). Over-estimation of acute CBV lesion was present in 3/4 (75%) and 1/9 (11%) of patients with/without TDCi truncation, respectively. Conclusion: CTP-derived CBV lesion reversal is associated with TDCi truncation

  15. Cerebral blood volume calculated by dynamic susceptibility contrast-enhanced perfusion MR imaging: preliminary correlation study with glioblastoma genetic profiles.

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    Inseon Ryoo

    Full Text Available PURPOSE: To evaluate the usefulness of dynamic susceptibility contrast (DSC enhanced perfusion MR imaging in predicting major genetic alterations in glioblastomas. MATERIALS AND METHODS: Twenty-five patients (M:F = 13∶12, mean age: 52.1±15.2 years with pathologically proven glioblastoma who underwent DSC MR imaging before surgery were included. On DSC MR imaging, the normalized relative tumor blood volume (nTBV of the enhancing solid portion of each tumor was calculated by using dedicated software (Nordic TumorEX, NordicNeuroLab, Bergen, Norway that enabled semi-automatic segmentation for each tumor. Five major glioblastoma genetic alterations (epidermal growth factor receptor (EGFR, phosphatase and tensin homologue (PTEN, Ki-67, O6-methylguanine-DNA methyltransferase (MGMT and p53 were confirmed by immunohistochemistry and analyzed for correlation with the nTBV of each tumor. Statistical analysis was performed using the unpaired Student t test, ROC (receiver operating characteristic curve analysis and Pearson correlation analysis. RESULTS: The nTBVs of the MGMT methylation-negative group (mean 9.5±7.5 were significantly higher than those of the MGMT methylation-positive group (mean 5.4±1.8 (p = .046. In the analysis of EGFR expression-positive group, the nTBVs of the subgroup with loss of PTEN gene expression (mean: 10.3±8.1 were also significantly higher than those of the subgroup without loss of PTEN gene expression (mean: 5.6±2.3 (p = .046. Ki-67 labeling index indicated significant positive correlation with the nTBV of the tumor (p = .01. CONCLUSION: We found that glioblastomas with aggressive genetic alterations tended to have a high nTBV in the present study. Thus, we believe that DSC-enhanced perfusion MR imaging could be helpful in predicting genetic alterations that are crucial in predicting the prognosis of and selecting tailored treatment for glioblastoma patients.

  16. The influence of local pressure on evaluation parameters of skin blood perfusion and fluorescence

    Science.gov (United States)

    Zherebtsov, E. A.; Kandurova, K. Y.; Seryogina, E. S.; Kozlov, I. O.; Dremin, V. V.; Zherebtsova, A. I.; Dunaev, A. V.; Meglinski, I.

    2017-03-01

    This article presents the results of the study of the pressure applied on optical diagnostic probes as a significant factor affecting the results of measurements. During stepwise increasing and decreasing of local pressure on skin we conducted measurements using the methods of laser Doppler flowmetry and fluorescence spectroscopy. It was found out that pressure on optical probe has sufficient impact on skin microcirculation to affect registered fluorescence intensity. Data obtained in this study are of interest for design and development of diagnostic technologies for wearable devices. This data will also inform further investigation into issues of compensation of blood absorption influence on fluorescence spectrum, allowing increased accuracy and reproducibility of measurements by fluorescence spectroscopy methods in optical diagnosis.

  17. Continuous Perfusion of Saphenous Vein by Oxygenated Blood during Beating Coronary Surgery

    Directory of Open Access Journals (Sweden)

    Mohammad Hossein Mandegar

    2015-09-01

    Full Text Available Background: The saphenous vein remains the most commonly used conduit for coronary artery bypass surgery (CABG. However, the long-term success of surgical revascularization is largely limited by development of occlusion in vein grafts. Objectives: We sought to reduce graft ischemia by maintaining the blood flow into the harvested vein throughout surgery at lowest costs and without special devices. Patients and Methods: This study was conducted on three hundred patients aged 58.5 ± 8 years undergoing elective first-time off-pump CABG with saphenous veins. Results: In addition to preserving nutritional materials and oxygen, the veins harvested via this novel technique did not go into spasm and were not subjected to high-pressure distension, eventually resulting in minimal damage to the endothelium. Conclusions: This technique confers favorable myocardial function and protection in the presence of left ventricular dysfunction, especially in elderly patients.

  18. Spectral analysis of blood perfusion in the free latissimus dorsi myocutaneous flap and in normal skin

    Energy Technology Data Exchange (ETDEWEB)

    Liu Xudong [Department of Orthopaedic Surgery, Shanghai No. 6 People' s Hospital, Shanghai Jiao Tong University, 600 Yishan Road, Shanghai 200233 (China); Zeng Bingfang [Department of Orthopaedic Surgery, Shanghai No. 6 People' s Hospital, Shanghai Jiao Tong University, 600 Yishan Road, Shanghai 200233 (China); Fan Cunyi [Department of Orthopaedic Surgery, Shanghai No. 6 People' s Hospital, Shanghai Jiao Tong University, 600 Yishan Road, Shanghai 200233 (China); Jiang Peizhu [Department of Orthopaedic Surgery, Shanghai No. 6 People' s Hospital, Shanghai Jiao Tong University, 600 Yishan Road, Shanghai 200233 (China); Hu Xiao [Department of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030 (China)

    2006-01-07

    To find the properties in the oscillatory components of the cutaneous blood flow on the successful free flap, a wavelet transform was applied to the laser Doppler flowmetry (LDF) signals which were measured simultaneously on the surfaces of the free latissimus dorsi myocutaneous flap and on the adjacent intact skin of the healthy limb, of 18 patients. The frequency interval from 0.0095 to 1.6 Hz was examined and was divided into five subintervals (I: 0.0095-0.021 Hz; II: 0.021-0.052 Hz; III: 0.052-0.145 Hz; IV: 0.145-0.6 Hz and V: 0.6-1.6 Hz) corresponding to endothelial metabolic, neurogenic, myogenic, respiratory and cardiac origins. The average amplitude and total power in the frequency range 0.0095-1.6 Hz as well as within subintervals I, II, IV and V were significantly lower for signals measured on the free flap than those obtained in the healthy limb. However in interval III, they were significantly higher. The normalized spectral amplitude and power in the free flap were significantly lower in only two intervals, I and II, yet in interval III they were significantly higher; no statistical significance was observed in intervals IV and V. The distinctive finding made in this study, aside from the decrease of endothelial metabolic processes and sympathetic control, was the significant increase of myogenic activity in the free flap. It is hoped that this work will contribute towards knowledge on blood circulation in free flaps and make the monitoring by LDF more reliable.

  19. Deuterium Nuclear Magnetic Resonance Measurements of Blood Flow and Tissue Perfusion Employing 2H2O as a Freely Diffusible Tracer

    Science.gov (United States)

    Ackerman, Joseph J. H.; Ewy, Coleen S.; Becker, Nancy N.; Shalwitz, Robert A.

    1987-06-01

    The use of deuterium oxide (2H2O) is proposed as a freely diffusible nuclear magnetic resonance (NMR) blood flow and tissue perfusion tracer of potential clinical utility. Deuterium is a stable, nonradiative isotope commercially available as 2H2O at enrichment levels of essentially 100%--i.e., 110 molar equivalent deuterium. This high concentration, together with the short relaxation time of the spin 1 (quadrupole) deuterium nuclide, provides substantial sensitivity for NMR spectroscopy. As a result, when 2H2O is administered in a bolus fashion to a specific tissue or organ in vivo, the deuterium NMR intensity time course can be analyzed, using mathematical models developed by others for radiolabeled tracers, to measure the rate of blood flow and tissue perfusion. Such an application is demonstrated herein at a static magnetic field of 8.5 tesla. Using single-compartment flow modeling, hepatic blood flow and tissue perfusion in fasted (18 hr) male Sprague-Dawley rats was determined to be 61 ± 17 (mean ± SD) ml/100 g per min (n = 5).

  20. Clinical and Experimental Study of Effects of Rhubarb on Gastrointestinal Blood Flow Perfusion in Critical Illness

    Institute of Scientific and Technical Information of China (English)

    CHEN; De-chang

    2001-01-01

    [1]Border JR. Multiple system organ failure. Ann Surg 1992;216(2)∶111-116.[2]Schiessel R, Feil W, Wenzel E. Mechanisms of stress ulceration and implications for treatment. Gastroenterol Clin North Am 1990;19(1)∶101-120.[3]CHEN DC, YANG JD, YANG XY, et al. The effects of rhubarb on permeability of intestinal mucosa and blood vessel in shocked rats. Chin Crit Care Med 1997;9(7)∶385-387.[4]CHEN DC, JING BW. The effects of rhubarb on the protection of gut barrier. Chin Crit Care Med 1994;6(6)∶329-331.[5]American College of Chest Physician/Society of Critical Care Medicine Consensus: Definitions for sepsis and organ failure and guidelines for the use of innovative therapies in sepsis. Crit Care Med 1992;20(6)∶864-874.[6]CHEN DC, JING BW, YANG XY, et al. Therapeutic effects of rhubarb on gastrointestinal failure. Med J Chin PLA 1996;21(1)∶24-26.[7]Nakayama SE. Infusion of very hypertonic saline to bled rats: membrane potential and fluid shifts. J Surg Res 1985;38(2)∶180-186.[8]Bulkley GB. Relationship of blood flow and oxygen consumption to ischemic injury in the canine small intestine. Gastroenterology 1985;89(4)∶852-857.[9]Marshall JC, Christon NV, Meakins JL, et al. The gastrointestinal tract: The “undrained abscess” of multiple organ failure. Ann Surg 1993;218(2)∶111-119.[10].Fiddiann-Green RG, McGough E, Pittenger G, et al. Predictive value of intramural pH and other risk factors for massive bleeding from stress ulceration. Gastroenterology. 1983;85(3)∶613-620.[11].ZHU L, YANG ZC, LI A. Changes and significance of the ability of gastric acid excretion during burn shock in rats. Chin Crit Care Med 1997;9(7)∶398-399.[12].JIAO DH, CHEN SX, ZHANG GH, et al. Clinical study of the effects of rhubarb on peptic ulcer with hemorrhage. CJITWM 1984;10(10)∶597-599.[13].YU JD, GONG LS. Effects of rhubarb on thromboxane A2 and prostacyclin in circulation blood in healthy people and acute myocardial

  1. Myocardial Perfusion Scintigraphy: Techniques, Interpretation, Indications and Reporting

    OpenAIRE

    Fathala, Ahmed

    2011-01-01

    Myocardial perfusion single photon emission-computed tomography (MPS) has been one of the most important and common non-invasive diagnostic cardiac test. Gated MPS provides simultaneous assessment of myocardial perfusion and function with only one study. With appropriate attention to the MPS techniques, appropriate clinical utilization and effective reporting, gated MPS will remain a useful diagnostic test for many years to come. The aim of this article is to review the basic techniques of MP...

  2. Study on Blood Perfusion of Normal Femur Heads Epiphyses in Piglets by Multi-Slice CT Perfusion%正常乳猪股骨头骨骺的MSCT灌注研究

    Institute of Scientific and Technical Information of China (English)

    黄春元; 罗帝林; 赵志清; 许朝璇; 梁焕莲; 吴冬; 冯登殿

    2011-01-01

    Objective To evaluate the blood perfusion of epiphyses, physis and metaphysis in normal femur heads of piglets by using multi-slice CT perfusion techniques. Methods Fifty five piglets(2 weeks old) were scanned by MSCT perfusion. The data of creating dynamic picture were analyzed, and the dynamic pictures of 26 femur heads were obtained completely. Every parameters including blood flow(BF) ,blood volume(BV) ,mean transit time(MTT) and time to peak(TTP) were analyzed,and compared with the histological findings. Results The BF of physis was higher than that of epiphysis( P <0.05 ). The BV of metaphysis was the highest in all anatomic regions( P <0.05). The MTT of epiphysis was the longest( P <0.05). There was no significant difference in MTT between physis and metaphysis( P >0.05 ). The TTP of physis was the shortest( P <0.05 ) ,and the other two were the same. CT perfusion imaging coincided with the histological results of the locations and concentrations of blood vessels in epiphyses,physis and metaphysis. Conclusion MSCT perfusion images can demonstrate the perfusion features in the various anatomic regions of femur heads.%目的 运用多层螺旋CT灌注技术评价正常乳猪股骨头骨骺、骺板软骨、干骺端等不同解剖区域的血液供应特征.方法 对15只2周龄的健康乳猪进行多层螺旋CT电影模式灌注扫描,对生成的动态图像数据进行测量分析,共获得26个股骨头的完整图像资料,统计并比较血流量(BF)、血容量(BV)、平均通过时间(MTT)、对比剂到达峰值时间(TTP),并与相应组织学表现进行时照.结果 骺板软骨的BF比骨骺的BF有明显增高(P0.05).各解剖区域中骺板软骨的TTP最短(P<0.05),骨骺与干骺端的TTP基本相同.组织学发现骨骺、骺板软骨、干骺端的血管密度分布特征与相应部位的CT增强率所提示的血供状态基本吻合.结论 多层螺旋CT灌注能够显示股骨头不同解剖区域的血液灌注特征.

  3. Non-invasive assessment of liver fibrosis in chronic liver diseases: Implementation in clinical practice and decisional algorithms

    Institute of Scientific and Technical Information of China (English)

    Giada Sebastiani

    2009-01-01

    Chronic hepatitis B and C together with alcoholic and non-alcoholic fatty liver diseases represent the major causes of progressive liver disease that can eventually evolve into cirrhosis and its end-stage complications, including decompensation, bleeding and liver cancer. Formation and accumulation of fibrosis in the liver is the common pathway that leads to an evolutive liver disease. Precise definition of liver fibrosis stage is essential for management of the patient in clinical practice since the presence of bridging fibrosis represents a strong indication for antiviral therapy for chronic viral hepatitis, while cirrhosis requires a specific follow-up including screening for esophageal varices and hepatocellular carcinoma. Liver biopsy has always represented the standard of reference for assessment of hepatic fibrosis but it has some limitations being invasive, costly and prone to sampling errors. Recently, blood markers and instrumental methods have been proposed for the non-invasive assessment of liver fibrosis. However, there are still some doubts as to their implementation in clinical practice and a real consensus on how and when to use them is not still available. This is due to an unsatisfactory accuracy for some of them, and to an incomplete validation for others. Some studies suggest that performance of non-invasive methods for liver fibrosis assessment may increase when they re combined. Combination algorithms of non-invasive methods for assessing liver fibrosis may represent a rational and reliable approach to implement noninvasive assessment of liver fibrosis in clinical practice and to reduce rather than abolish liver biopsies.

  4. Psychiatric profiles and patterns of cerebral blood flow in focal epilepsy: interactions between depression, obsessionality, and perfusion related to the laterality of the epilepsy.

    Science.gov (United States)

    Schmitz, E B; Moriarty, J; Costa, D C; Ring, H A; Ell, P J; Trimble, M R

    1997-01-01

    OBJECTIVES: In a study of patients with focal epilepsy the hypothesis was explored that different measurements of psychopathology are related to specific distributions of cerebral perfusion. METHODS: Forty patients had SPECT performed with (99m)Tc-HMPAO. In addition, patients received a psychiatric evaluation with the following psychiatric questionnaires: the Beck depression inventory, the Leyton obsessionality inventory, the Bear-Fedio questionnaire, and the social stress and support interview. Patients were analysed in two groups according to the laterality of the epilepsy. Nine patients were excluded based on poor quality scans (n = 1), unlateralised epilepsy (n = 4), and left or ambidextrous handedness (n = 4). RESULTS: There were no overall differences between the left and right epilepsy groups on measures of psychopathology. Associations were found between scores on some of the rating scales and regional cerebral blood flow. Specifically, for patients with left sided epilepsy, higher scores on the Beck depression inventory were associated with lower contralateral temporal and bilateral frontal perfusion, and higher occipital perfusion. For patients with right sided epilepsy higher scores on the Leyton obsessionality inventory were associated with increased perfusion in ipsilateral temporal, thalamic, and basal ganglia regions and bilateral frontal regions. CONCLUSION: The results do not support the notion that lateralised epileptogenic lesions are associated with different levels of depression, obsessionality, or personality traits. They support the view that certain psychopathological symptom patterns are related to specific regional dysfunctions depending on the laterality of a hemispheric lesion. PMID:9153601

  5. Validation of Perfusion Quantification with 3D Gradient Echo Dynamic Contrast-Enhanced Magnetic Resonance Imaging Using a Blood Pool Contrast Agent in Skeletal Swine Muscle.

    Directory of Open Access Journals (Sweden)

    Stefan Hindel

    Full Text Available The purpose of our study was to validate perfusion quantification in a low-perfused tissue by dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI with shared k-space sampling using a blood pool contrast agent. Perfusion measurements were performed in a total of seven female pigs. An ultrasonic Doppler probe was attached to the right femoral artery to determine total flow in the hind leg musculature. The femoral artery was catheterized for continuous local administration of adenosine to increase blood flow up to four times the baseline level. Three different stable perfusion levels were induced. The MR protocol included a 3D gradient-echo sequence with a temporal resolution of approximately 1.5 seconds. Before each dynamic sequence, static MR images were acquired with flip angles of 5°, 10°, 20°, and 30°. Both static and dynamic images were used to generate relaxation rate and baseline magnetization maps with a flip angle method. 0.1 mL/kg body weight of blood pool contrast medium was injected via a central venous catheter at a flow rate of 5 mL/s. The right hind leg was segmented in 3D into medial, cranial, lateral, and pelvic thigh muscles, lower leg, bones, skin, and fat. The arterial input function (AIF was measured in the aorta. Perfusion of the different anatomic regions was calculated using a one- and a two-compartment model with delay- and dispersion-corrected AIFs. The F-test for model comparison was used to decide whether to use the results of the one- or two-compartment model fit. Total flow was calculated by integrating volume-weighted perfusion values over the whole measured region. The resulting values of delay, dispersion, blood volume, mean transit time, and flow were all in physiologically and physically reasonable ranges. In 107 of 160 ROIs, the blood signal was separated, using a two-compartment model, into a capillary and an arteriolar signal contribution, decided by the F-test. Overall flow in hind leg muscles

  6. Validation of Perfusion Quantification with 3D Gradient Echo Dynamic Contrast-Enhanced Magnetic Resonance Imaging Using a Blood Pool Contrast Agent in Skeletal Swine Muscle.

    Science.gov (United States)

    Hindel, Stefan; Sauerbrey, Anika; Maaß, Marc; Maderwald, Stefan; Schlamann, Marc; Lüdemann, Lutz

    2015-01-01

    The purpose of our study was to validate perfusion quantification in a low-perfused tissue by dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) with shared k-space sampling using a blood pool contrast agent. Perfusion measurements were performed in a total of seven female pigs. An ultrasonic Doppler probe was attached to the right femoral artery to determine total flow in the hind leg musculature. The femoral artery was catheterized for continuous local administration of adenosine to increase blood flow up to four times the baseline level. Three different stable perfusion levels were induced. The MR protocol included a 3D gradient-echo sequence with a temporal resolution of approximately 1.5 seconds. Before each dynamic sequence, static MR images were acquired with flip angles of 5°, 10°, 20°, and 30°. Both static and dynamic images were used to generate relaxation rate and baseline magnetization maps with a flip angle method. 0.1 mL/kg body weight of blood pool contrast medium was injected via a central venous catheter at a flow rate of 5 mL/s. The right hind leg was segmented in 3D into medial, cranial, lateral, and pelvic thigh muscles, lower leg, bones, skin, and fat. The arterial input function (AIF) was measured in the aorta. Perfusion of the different anatomic regions was calculated using a one- and a two-compartment model with delay- and dispersion-corrected AIFs. The F-test for model comparison was used to decide whether to use the results of the one- or two-compartment model fit. Total flow was calculated by integrating volume-weighted perfusion values over the whole measured region. The resulting values of delay, dispersion, blood volume, mean transit time, and flow were all in physiologically and physically reasonable ranges. In 107 of 160 ROIs, the blood signal was separated, using a two-compartment model, into a capillary and an arteriolar signal contribution, decided by the F-test. Overall flow in hind leg muscles, as measured by the

  7. Non-invasive prenatal testing of trisomy 18 by an epigenetic marker in first trimester maternal plasma.

    Directory of Open Access Journals (Sweden)

    Da Eun Lee

    Full Text Available BACKGROUND: Quantification of cell-free fetal DNA by methylation-based DNA discrimination has been used in non-invasive prenatal testing of fetal chromosomal aneuploidy. The maspin (Serpin peptidase inhibitor, clade B (ovalbumin, member 5; SERPINB5 gene, located on chromosome 18q21.33, is hypomethylated in the placenta and completely methylated in maternal blood cells. The objective of this study was to evaluate the accuracy of non-invasive detection of fetal trisomy 18 using the unmethylated-maspin (U-maspin gene as a cell-free fetal DNA marker and the methylated-maspin (M-maspin gene as a cell-free total DNA marker in the first trimester of pregnancy. METHODOLOGY/PRINCIPAL FINDINGS: A nested case-control study was conducted using maternal plasma collected from 66 pregnant women, 11 carrying fetuses with trisomy 18 and 55 carrying normal fetuses. Median U-maspin concentrations were significantly elevated in women with trisomy 18 fetuses compared with controls (27.2 vs. 6.7 copies/mL; P<0.001. Median M-maspin concentrations were also significantly higher in women with trisomy 18 fetuses than in controls (96.9 vs. 19.5 copies/mL, P<0.001. The specificities of U-maspin and M-maspin concentrations for non-invasive fetal trisomy 18 detection were 96.4% and 74.5%, respectively, with a sensitivity of 90.9%. CONCLUSIONS: Our results suggest that U-maspin and M-maspin concentrations may be useful as potential biomarkers for non-invasive detection of fetal trisomy 18 in the first trimester of pregnancy, irrespective of the sex and genetic variations of the fetus.

  8. Using Non-Invasive Multi-Spectral Imaging to Quantitatively Assess Tissue Vasculature

    Energy Technology Data Exchange (ETDEWEB)

    Vogel, A; Chernomordik, V; Riley, J; Hassan, M; Amyot, F; Dasgeb, B; Demos, S G; Pursley, R; Little, R; Yarchoan, R; Tao, Y; Gandjbakhche, A H

    2007-10-04

    This research describes a non-invasive, non-contact method used to quantitatively analyze the functional characteristics of tissue. Multi-spectral images collected at several near-infrared wavelengths are input into a mathematical optical skin model that considers the contributions from different analytes in the epidermis and dermis skin layers. Through a reconstruction algorithm, we can quantify the percent of blood in a given area of tissue and the fraction of that blood that is oxygenated. Imaging normal tissue confirms previously reported values for the percent of blood in tissue and the percent of blood that is oxygenated in tissue and surrounding vasculature, for the normal state and when ischemia is induced. This methodology has been applied to assess vascular Kaposi's sarcoma lesions and the surrounding tissue before and during experimental therapies. The multi-spectral imaging technique has been combined with laser Doppler imaging to gain additional information. Results indicate that these techniques are able to provide quantitative and functional information about tissue changes during experimental drug therapy and investigate progression of disease before changes are visibly apparent, suggesting a potential for them to be used as complementary imaging techniques to clinical assessment.

  9. Non-invasive hyperthermia apparatus including coaxial applicator having a non-invasive radiometric receiving antenna incorporated therein and method of use