Journal articles: 'ICP Method'

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WANG, ZiWei, XiaoJian ZHANG, SiJie YAN, and Xing DAI. "Sparse mixed ICP registration method." SCIENTIA SINICA Technologica 51, no. 7 (March 12, 2021): 837–49. http://dx.doi.org/10.1360/sst-2020-0287.

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Yu, Young-Ki, Ja-Myung Koo, Min-Soo Oh, and Il-Dong Yang. "Rail Profile Matching Method using ICP Algorithm." Transactions of The Korean Institute of Electrical Engineers 65, no. 5 (May 1, 2016): 888–94. http://dx.doi.org/10.5370/kiee.2016.65.5.888.

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Luciano, Mark G., Stephen M. Dombrowski, Sara Qvarlander, Serge El-Khoury, Jun Yang, Suraj Thyagaraj, and Francis Loth. "Novel method for dynamic control of intracranial pressure." Journal of Neurosurgery 126, no. 5 (May 2017): 1629–40. http://dx.doi.org/10.3171/2016.4.jns152457.

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OBJECTIntracranial pressure (ICP) pulsations are generally considered a passive result of the pulsatility of blood flow. Active experimental modification of ICP pulsations would allow investigation of potential active effects on blood and CSF flow and potentially create a new platform for the treatment of acute and chronic low blood flow states as well as a method of CSF substance clearance and delivery. This study presents a novel method and device for altering the ICP waveform via cardiac-gated volume changes.METHODSThe novel device used in this experiment (named Cadence) consists of a small air-filled inelastic balloon (approximately 1.0 ml) implanted into the intracranial space and connected to an external programmable pump, triggered by an R-wave detector. Balloons were implanted into the epidural space above 1 of the hemispheres of 19 canines for up to 10 hours. When activated, the balloons were programed to cyclically inflate with the cardiac cycle with variable delay, phase, and volume. The ICP response was measured in both hemispheres. Additionally, cerebral blood flow (heat diffusion and laser Doppler) was studied in 16 canines.RESULTSThis system, depending on the inflation pattern of the balloon, allowed a flattening of the ICP waveform, increase in the ICP waveform amplitude, or phase shift of the wave. This occurred with small mean ICP changes, typically around ± 2 mm Hg (15%). Bilateral ICP effects were observed with activation of the device: balloon inflation at each systole increased the systolic ICP pulse (up to 16 mm Hg, 1200%) and deflation at systole decreased or even inverted the systolic ICP pulse (−0.5 to −19 mm Hg, −5% to −1600%) in a dose-(balloon volume) dependent fashion. No aphysiological or deleterious effects on systemic pressure (≤ ±10 mm Hg; 13% change in mean pressure) or cardiac rate (≤ ± 17 beats per minute; 16% change) were observed during up to 4 hours of balloon activity.CONCLUSIONSThe results of these initial studies using an intracranially implanted, cardiac-gated, volume-oscillating balloon suggest the Cadence device can be used to modify ICP pulsations, without physiologically deleterious effects on mean ICP, systemic vascular effects, or brain injury. This device and technique may be used to study the role of ICP pulsatility in intracranial hemo- and hydrodynamic processes and introduces the creation of a potential platform of a cardiac-gated system for treatment of acute and chronic low blood flow states, and diseases requiring augmentation of CSF substance clearance or delivery.

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He, Shi Jun, Shi Ting Zhao, Fan Bai, and Jia Wei. "A Method for Spatial Data Registration Based on PCA-ICP Algorithm." Advanced Materials Research 718-720 (July 2013): 1033–36. http://dx.doi.org/10.4028/www.scientific.net/amr.718-720.1033.

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The spatial data which acquired by 3D laser scanning is huge, aiming at the iteration time is long with classic ICP algorithm, a improved registration algorithm of spatial data ICP algorithm which based on principal component analysis (PCA) is proposed in this paper (PCA-ICP), the basic principle and steps of PCA-ICP algorithm are given. The experiment results show that this method is feasible and the iterative time of PCA-ICP algorithm is shorter than classical ICP algorithm.

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Kienzler, Jenny C., Rolandas Zakelis, Sabrina Bäbler, Elke Remonda, Arminas Ragauskas, and Javier Fandino. "Validation of Noninvasive Absolute Intracranial Pressure Measurements in Traumatic Brain Injury and Intracranial Hemorrhage." Operative Neurosurgery 16, no. 2 (May 3, 2018): 186–96. http://dx.doi.org/10.1093/ons/opy088.

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Abstract BACKGROUND Increased intracranial pressure (ICP) causes secondary damage in traumatic brain injury (TBI), and intracranial hemorrhage (ICH). Current methods of ICP monitoring require surgery and carry risks of complications. OBJECTIVE To validate a new instrument for noninvasive ICP measurement by comparing values obtained from noninvasive measurements to those from commercial implantable devices through this pilot study. METHODS The ophthalmic artery (OA) served as a natural ICP sensor. ICP measurements obtained using noninvasive, self-calibrating device utilizing Doppler ultrasound to evaluate OA flow were compared to standard implantable ICP measurement probes. RESULTS A total of 78 simultaneous, paired, invasive, and noninvasive ICP measurements were obtained in 11 ICU patients over a 17-mo period with the diagnosis of TBI, SAH, or ICH. A total of 24 paired data points were initially excluded because of questions about data independence. Analysis of variance was performed first on the 54 remaining data points and then on the entire set of 78 data points. There was no difference between the 2 groups nor was there any correlation between type of sensor and the patient (F[10, 43] = 1.516, P = .167), or the accuracy and precision of noninvasive ICP measurements (F[1, 43] = 0.511, P = .479). Accuracy was [−1.130; 0.539] mm Hg (CL = 95%). Patient-specific calibration was not needed. Standard deviation (precision) was [1.632; 2.396] mm Hg (CL = 95%). No adverse events were encountered. CONCLUSION This pilot study revealed no significant differences between invasive and noninvasive ICP measurements (P < .05), suggesting that noninvasive ICP measurements obtained by this method are comparable and reliable.

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Behmanesh, Bedjan, Marco Bartels, Florian Gessler, Natalie Filmann, Volker Seifert, Matthias Setzer, and Thomas M. Freiman. "Noninvasive Transfontanelle Monitoring of the Intracerebral Pressure in Comparison With an Invasive Intradural Intracranial Pressure Device: A Prospective Study." Operative Neurosurgery 13, no. 5 (March 9, 2017): 609–13. http://dx.doi.org/10.1093/ons/opx024.

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Abstract BACKGROUND: We previously introduced a novel noninvasive technique of intracranial pressure (ICP) monitoring in children with open fontanelles. OBJECTIVE: To compare the ICP obtained by our new technique to the ICP derived from an intradurally implanted ICP measurement device (external ventricular drain, subdural ICP device). METHODS: Children with open fontanelles and need of intracranial monitoring were included in this study. A standard ICP probe was placed upon the frontal fontanelle and data were compared with the values recorded by an already invasively implanted subdural ICP technique. The 2 methods of ICP measurement were evaluated using the correlation coefficient, Bland and Altman method and method comparison by Carstensen. RESULTS: Five children under the age of 1 year with an open frontal fontanelle were included in this study. Three were male and 2 were female. Mean age was 7 months. A total of 139 pairs of measurements were assessed. Mean transfontanelle ICP was 7.6 mm Hg. Mean ICP measured subdurally was 5.4 mm Hg. The correlation analysis showed a correlation coefficient of 0.7. The Bland-Altman plot revealed a good accuracy of the new method with >95% of the values within the limits of agreement. An additional method comparison analysis confirmed the finding of accurate ICP measurements between both applied methods. CONCLUSION: The noninvasive transfontanelle ICP monitoring method displayed a high validity and reliability as proven by correlation analysis. This novel technique might therefore be an interesting and promising tool for noninvasive ICP monitoring in children. But further research is necessary to evaluate the accuracy of this technique in children with elevated ICP.

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Schmidt, Bernhard, Marek Czosnyka, Jens Jürgen Schwarze, Dirk Sander, Werner Gerstner, Christianto Benjamin Lumenta, John D. Pickard, and Jürgen Klingelhöfer. "Cerebral Vasodilatation Causing Acute Intracranial Hypertension: A Method for Noninvasive Assessment." Journal of Cerebral Blood Flow & Metabolism 19, no. 9 (September 1999): 990–96. http://dx.doi.org/10.1097/00004647-199909000-00006.

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Deep spontaneous vasodilatatory events are frequently recorded in various cerebral diseases, causing dramatic increases (A-waves) in intracranial pressure (ICP) and subsequently provoking ischemic brain insults, The relationship between fluctuations in CBF, ICP, and arterial blood pressure (ABP) is influenced by properties of cerebrovascular control mechanisms and the cerebrospinal pressure-volume compensation, The goal of this study was to construct a mathematical model of this relationship and to assess its ability to predict the occurrence and time course of A-waves, A group of 17 severely head-injured patients were included in the study, In our model ICP was derived from the ABP waveform using a linear signal transformation. The transformation was modified during the simulation by a relationship between ABP and flow velocity, i.e., by the characterization of the cerebrovascular bed. In this way the ICP could be calculated from the ABP waveform. This model was verified by comparison of simulated and directly measured ICP during A-waves recorded in seven of the patients. In all simulations, plateau elevations of ICP were well replicated. The mean absolute error between real and simulated ICP was 8.3 ± 5.4 mm Hg at the baseline and 7.9 ± 4.3 mm Hg at the top of plateau waves. The correlation coefficient between real and simulated increase in ICP was R = 0.98; P < .001. Similarly, correlation between real and simulated increase in pulse amplitude of ICP was highly significant (R = 0.94; P < .001). The mathematical model of the relationship between ABP, flow velocity, and ICP is of potential clinical use for the noninvasive detection of A-waves in patients in whom invasive ICP assessment is not conducted.

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Yan, Ying, Qi Xia, and Ke Wang. "Iterative Closest Point Method with a Least Trimmed Squares Estimator." Applied Mechanics and Materials 220-223 (November 2012): 1381–84. http://dx.doi.org/10.4028/www.scientific.net/amm.220-223.1381.

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The iterative closest point (ICP) method is one of the most important methods for 2D/3D point registration. Robust statistical method is applied widely for improving the robustness of ICP. A new method that incorporates the Least Trimmed Squares (LTS) Estimator into the ICP is proposed in this paper. In this method, outliers are removed according to characteristics of residual distribution. A large number of experimental results show that the proposed method is robust and efficient.

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Behrens, Anders, Niklas Lenfeldt, Khalid Ambarki, Jan Malm, Anders Eklund, and Lars-Owe Koskinen. "Transcranial Doppler Pulsatility Index: Not an Accurate Method to Assess Intracranial Pressure." Neurosurgery 66, no. 6 (June 1, 2010): 1050–57. http://dx.doi.org/10.1227/01.neu.0000369519.35932.f2.

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Abstract BACKGROUND Transcranial Doppler sonography (TCD) assessment of intracranial blood flow velocity has been suggested to accurately determine intracranial pressure (ICP). OBJECTIVE We attempted to validate this method in patients with communicating cerebrospinal fluid systems using predetermined pressure levels. METHODS Ten patients underwent a lumbar infusion test, applying 4 to 5 preset ICP levels. On each level, the pulsatility index (PI) in the middle cerebral artery was determined by measuring the blood flow velocity using TCD. ICP was simultaneously measured with an intraparenchymal sensor. ICP and PI were compared using correlation analysis. For further understanding of the ICP-PI relationship, a mathematical model of the intracranial dynamics was simulated using a computer. RESULTS The ICP-PI regression equation was based on data from 8 patients. For 2 patients, no audible Doppler signal was obtained. The equation was ICP = 23*PI + 14 (R2 = 0.22, P < .01, N = 35). The 95% confidence interval for a mean ICP of 20 mm Hg was −3.8 to 43.8 mm Hg. Individually, the regression coefficients varied from 42 to 90 and the offsets from −32 to +3. The mathematical simulations suggest that variations in vessel compliance, autoregulation, and arterial pressure have a serious effect on the ICP-PI relationship. CONCLUSIONS The in vivo results show that PI is not a reliable predictor of ICP. Mathematical simulations indicate that this is caused by variations in physiological parameters.

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Ganslandt, Oliver, Stylianos Mourtzoukos, Andreas Stadlbauer, Björn Sommer, and Rudolf Rammensee. "Evaluation of a novel noninvasive ICP monitoring device in patients undergoing invasive ICP monitoring: preliminary results." Journal of Neurosurgery 128, no. 6 (June 2018): 1653–60. http://dx.doi.org/10.3171/2016.11.jns152268.

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OBJECTIVEThere is no established method of noninvasive intracranial pressure (NI-ICP) monitoring that can serve as an alternative to the gold standards of invasive monitoring with external ventricular drainage or intraparenchymal monitoring. In this study a new method of NI-ICP monitoring performed using algorithms to determine ICP based on acoustic properties of the brain was applied in patients undergoing invasive ICP (I-ICP) monitoring, and the results were analyzed.METHODSIn patients with traumatic brain injury and subarachnoid hemorrhage who were undergoing treatment in a neurocritical intensive care unit, the authors recorded ICP using the gold standard method of invasive external ventricular drainage or intraparenchymal monitoring. In addition, the authors simultaneously measured the ICP noninvasively with a device (the HS-1000) that uses advanced signal analysis algorithms for acoustic signals propagating through the cranium. To assess the accuracy of the NI-ICP method, data obtained using both I-ICP and NI-ICP monitoring methods were analyzed with MATLAB to determine the statistical significance of the differences between the ICP measurements obtained using NI-ICP and I-ICP monitoring.RESULTSData were collected in 14 patients, yielding 2543 data points of continuous parallel ICP values in recordings obtained from I-ICP and NI-ICP. Each of the 2 methods yielded the same number of data points. For measurements at the ≥ 17–mm Hg cutoff, which was arbitrarily chosen for this preliminary analysis, the sensitivity and specificity for the NI-ICP monitoring were found to be 0.7541 and 0.8887, respectively. Linear regression analysis indicated that there was a strong positive relationship between the measurements. Differential pressure between NI-ICP and I-ICP was within ± 3 mm Hg in 63% of data-paired readings and within ± 5 mm Hg in 85% of data-paired readings. The receiver operating characteristic–area under the curve analysis revealed that the area under the curve was 0.895, corresponding to the overall performance of NI-ICP monitoring in comparison with I-ICP monitoring.CONCLUSIONSThis study provides the first clinical data on the accuracy of the HS-1000 NI-ICP monitor, which uses advanced signal analysis algorithms to evaluate properties of acoustic signals traveling through the brain in patients undergoing I-ICP monitoring. The findings of this study highlight the capability of this NI-ICP device to accurately measure ICP noninvasively. Further studies should focus on clinical validation for elevated ICP values.

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Weigert, Claudia, Fabian Steffler, Tomas Kurz, Thomas H. Shellhammer, and Frank-Jï¿½rgen Methner. "Application of a Short Intracellular pH Method to Flow Cytometry for Determining Saccharomyces cerevisiae Vitality." Applied and Environmental Microbiology 75, no. 17 (July 6, 2009): 5615–20. http://dx.doi.org/10.1128/aem.00650-09.

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ABSTRACT The measurement of yeast's intracellular pH (ICP) is a proven method for determining yeast vitality. Vitality describes the condition or health of viable cells as opposed to viability, which defines living versus dead cells. In contrast to fluorescence photometric measurements, which show only average ICP values of a population, flow cytometry allows the presentation of an ICP distribution. By examining six repeated propagations with three separate growth phases (lag, exponential, and stationary), the ICP method previously established for photometry was transferred successfully to flow cytometry by using the pH-dependent fluorescent probe 5,6-carboxyfluorescein. The correlation between the two methods was good (r 2 = 0.898, n = 18). With both methods it is possible to track the course of growth phases. Although photometry did not yield significant differences between exponentially and stationary phases (P = 0.433), ICP via flow cytometry did (P = 0.012). Yeast in an exponential phase has a unimodal ICP distribution, reflective of a homogeneous population; however, yeast in a stationary phase displays a broader ICP distribution, and subpopulations could be defined by using the flow cytometry method. In conclusion, flow cytometry yielded specific evidence of the heterogeneity in vitality of a yeast population as measured via ICP. In contrast to photometry, flow cytometry increases information about the yeast population's vitality via a short measurement, which is suitable for routine analysis.

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Amais, Renata S., Joaquim A. Nóbrega, and George L. Donati. "The interference standard method: evidence of principle, potentialities and limitations." J. Anal. At. Spectrom. 29, no. 7 (2014): 1258–64. http://dx.doi.org/10.1039/c4ja00052h.

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Seddighi, Amir, Alireza Zadeh, Afsoun Seddighi, and Alireza Zali. "Accuracy of non-invasive intracranial pressure measurement." Open Medicine 7, no. 2 (April 1, 2012): 169–75. http://dx.doi.org/10.2478/s11536-011-0129-7.

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AbstractNon-invasive measurement of intracranial pressure (ICP) reduces the complications and cost for both patient and health care systems. Improvement of non-invasive methods has led to development of systems for reproducing continuous, real-time non-invasive ICP signals. So far, non-invasive methods have been tailored for the patients with head trauma. We have used Schmidt’s auto-adaptive method to assess the accuracy of this method for patients after surgery for supratentorial brain tumors. Data from forty patients with the diagnosis of brain tumor operated from 2008 to 2010 were used to estimate the accuracy of Schmidt’s method in our patients. We obtained the model parameters from 30 recordings. We determined the ICP wave form for the remaining patients by both invasive and non-invasive techniques. In the test group, by invasive method, the mean ICP±2SD was 17.1 ± 6.6 mmHg and using non-invasive method, the mean ICP ± 2SD was 16.5 ± 5.4 mmHg. The calculated error was 4.6 mmHg using root mean square errors. The average Pearson correlation between the estimated and real waveforms was 0.92. We believe that application of this method is acceptable for post-operative assessment of ICP in brain tumor patients.

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Firsching, Raimund, Michael Schütze, Markus Motschmann, and Wolfgang Behrens-Baumann. "Venous ophthalmodynamometry: a noninvasive method for assessment of intracranial pressure." Journal of Neurosurgery 93, no. 1 (July 2000): 33–36. http://dx.doi.org/10.3171/jns.2000.93.1.0033.

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Object. The goal of this study was to examine the potential use of ophthalmodynamometry in the noninvasive assessment of intracranial pressure (ICP). Under normal conditions, pressure within the central retinal vein is equal to or greater than ICP, because the central retinal vein passes through the optic nerve before it drains into the cavernous sinus. The optic nerve sheath is the place where ICP affects retinal venous pressure. Suction ophthalmodynamometry is an established method of investigation in ophthalmology to determine the pressure of the central retinal artery. Although observations of papilledema and lack of venous pulsations are commonly used to provide a vague assessment of ICP, ophthalmodynamometry may be used to determine the pressure of the central retinal vein. This venous pressure has never been compared with ICP.Methods. In this study the pressure of the central retinal vein was recorded in 22 patients who underwent continuous simultaneous registration of ICP for various reasons, mainly for suspected hydrocephalus. A comparison of the two pressures was made. The results indicated a highly significant linear correlation between central retinal vein pressure and ICP.These results are of great practical value because up-to-date reliable ICP monitoring has only been possible by using invasive means, by placing a probe extradurally or subdurally into the brain parenchyma or a ventricle.Conclusions. Ophthalmodynamometry can be relevant for momentary assessment and is not suitable for continuous monitoring. However, this technique can easily be repeated and may be used whenever increased ICP is suspected in a patient suffering from hydrocephalus, brain tumors, or head injury.

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Chen, Hui, Jian Wang, Sizhong Mao, Weiwei Dong, and Hao Yang. "A New Method of Intracranial Pressure Monitoring by EEG Power Spectrum Analysis." Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques 39, no. 4 (July 2012): 483–87. http://dx.doi.org/10.1017/s0317167100013998.

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Objectives:To investigate the feasibility of Electroencephalogram (EEG) power spectrum analysis as a noninvasive method for monitoring intracranial pressure (ICP).Methods:The EEG signals were recorded in 62 patients (70 cases) with central nervous system (CNS) disorders in our hospital. By using self-designed software, EEG power spectrum analysis was conducted and pressure index (PI) was calculated automatically. Intracranial pressure was measured by lumbar puncture (LP).Results:We found a significant negative correlation between PI and ICP (r = -0.849, p < 0.01).Conclusions:The PI obtained from EEG analysis is correlated with ICP. Analysis of specific parameters from EEG power spectrum might reflect the ICP.

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Michaeli, David, and Z. Harry Rappaport. "Tissue resonance analysis: a novel method for noninvasive monitoring of intracranial pressure." Journal of Neurosurgery 96, no. 6 (June 2002): 1132–37. http://dx.doi.org/10.3171/jns.2002.96.6.1132.

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✓ A number of noninvasive methods used to measure intracranial pressure (ICP) have been proposed in the literature. For a variety of reasons, however, none of these have displayed significant practical applicability. The authors describe their development of a new, computerized, portable device based on tissue resonance analysis (TRA) technology for the noninvasive monitoring and measurement of ICP. In response to the heart beat, the soft tissue and fluid compartments of the brain each exhibit characteristic vibration and mechanical resonant responses that radiate through the organs and tissues of the body. Patterns of vibration and mechanical resonance of various body organs and tissues are different and provide the possibility of extracting new and specific information in a noninvasive fashion. According to the TRA approach, ICP is dependent on the value of the dominant secondary (mechanical) resonance level of brain tissue. By digitally processing a reflected ultrasound signal (by using a concave ultrasonography probe with a carrier frequency of 1 MHz) from the third ventricle, the authors obtained a digital high-resolution echopulsogram, which visually is equivalent to ICP waves that are obtained invasively. The fast Fourier relationship of electrocardiogram and echopulsogram waves allowed the derivation of the secondary mechanical resonance levels. The authors developed a formula for a quantitative, noninvasive measurement of ICP, which uses information regarding multiple components of the intracranial space—both mechanical (secondary resonance) and physiological (time required for transfer of arterial blood to venous blood through brain tissue)—and the relationship between these components. A comparison of invasive and noninvasive ICP measurements was made during blinded trials in 40 patients with various diseases of the central nervous system, and ranges of ICP were measured from 1 to 66 mm Hg. The ICP values obtained using the two methods were highly correlated (r = 0.99), without a statistically significant difference between simultaneously obtained readings (p = 1). By using an integrative approach that reflects all components of the intracranial compartment, TRA allows for accurate noninvasive recordings of ICP. This method has significant advantages over other noninvasive technologies reported to date.

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North, Brian, and Peter Reilly. "Comparison among Three Methods of Intracranial Pressure Recording." Neurosurgery 18, no. 6 (June 1, 1986): 730–32. http://dx.doi.org/10.1227/00006123-198606000-00009.

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Abstract Fluid-coupled recording systems are the most popular method of recording intracranial pressure (ICP), but they can be prone to blockage and infection. A series of 378 recordings of ICP was analyzed to identify complications and cases in which recording had to be discontinued prematurely because of catheter blockage. Three different methods of ICP recording were used: a ventricular catheter, a Richmond screw, and a subdural catheter. Richmond screws became blocked more often (16%) than subdural catheters (2.7%) or ventricular catheters (2.5%). Complications of infection and intracerebral hemorrhage were observed mostly in the ventricular catheter patients. Of these three methods, a subdural catheter is the preferred method of recording ICP.

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Forte, Luis Vicente, Cássio Morano Peluso, Mirto Nelso Prandini, Roberto Godoy, and Salomon Soriano Ordinola Rojas. "Regional cooling for reducing brain temperature and intracranial pressure." Arquivos de Neuro-Psiquiatria 67, no. 2b (June 2009): 480–87. http://dx.doi.org/10.1590/s0004-282x2009000300019.

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OBJECTIVE: To evaluate the effectiveness of regional cooling for reducing brain temperature (BrTe) and intracranial pressure (ICP) in patients where conventional clinical treatment has failed. METHOD: Regional cooling was carried out using ice bags covering the area of the craniectomy (regional method) in 23 patients. The BrTe and ICP were determined using a fiber optic sensor. Thirteen patients (56.52%) were female. The ages ranged from 16 to 83 years (mean of 48.9). The mean APACHE II score was 25 points (11-35). The patients were submitted, on mean, to 61.7 hours (20-96) of regional cooling. RESULTS: There was a significant reduction in mean BrTe (p<0.0001-from 37.1ºC to 35.2ºC) and mean ICP (p=0.0001-from 28 mmHg to 13 mmHg). CONCLUSION: Our results suggest that mild brain hypothermia induced by regional cooling was effective in the control of ICP in patients who had previously undergone decompressive craniectomy.

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Andreytseva, M. I., S. S. Petrikov, L. T. Khamidova, and A. A. Solodov. "The ultrasound study of the optic canal for detecting raised intracranial pressure (a literature review and critical analysis)." Russian Sklifosovsky Journal "Emergency Medical Care" 7, no. 4 (January 30, 2019): 349–56. http://dx.doi.org/10.23934/2223-9022-2018-74-349-356.

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Intracranial hypertension (ICH) is a frequent and serious complication that occurs in pa-tients with severe traumatic brain injury (TBI) and nontraumatic brain damage. Persistent ICH significantly worsens the prognosis of the disease course and increases the risk of adverse outcomes. In this regard, one of the main tasks of intensive care of patients with intracranial bleeding (ICB) is diagnosis and timely management of ICH. The gold standard is invasive intracranial pressure (ICP) monitoring. The advantages of direct measurement of ICP include accuracy and continuity of registration. The disadvantages are the invasiveness of the method, high cost, the risk of developing infectious and hemorrhagic complications and possible dislocation of sensors. It is necessary to search for a method of non-invasive assessment of the level of ICH most correlated with the data of direct measurement of ICP. Ultrasonography of the optic nerve structures can be such an alternative cheap way to assess ICP. Its advantages are the possibility of repeated dynamic use, no need for surgical intervention, simplicity and high accuracy of measurement. However, the results obtained with ultrasound vary, since this method is operator dependent and requires precise adherence to the technique of the study. When the optic nerve ultrasound is performed, a contact gel for ultrasound examinations is applied to the anterolateral surface of the closed upper eyelid, and a scanning plane is displayed behind the eyeball for visualization in the central part of the ultrasound image of the optic nerve, lens and retina. To visualize the vertical course of the ophthalmic artery (and the vertical course of the optic nerve), the color flow Doppler mode is used. The study includes measuring the diameter of the optic nerve and the optic nerve sheath diameter (ONSD). There is subarachnoid space with cerebrospinal fluid between the optic nerve and its sheath. With an increase in intracranial pressure, the expansion of this space occurs, ONSD grows as well. This article contains an analysis of the literature describing the anatomy of the optic nerve and various ultrasound techniques, as well as data from various authors on the threshold value of the optic nerve sheath diameter.

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Marmarou, Anthony, Randy L. Anderson, John D. Ward, Sung C. Choi, Harold F. Young, Howard M. Eisenberg, Mary A. Foulkes, Lawrence F. Marshall, and John A. Jane. "NINDS Traumatic Coma Data Bank: intracranial pressure monitoring methodology." Journal of Neurosurgery 75, Supplement (November 1991): S21—S27. http://dx.doi.org/10.3171/sup.1991.75.1s.0s21.

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✓ This report describes the methods used by the Traumatic Coma Data Bank (TCDB) for acquisition and recording of intracranial pressure (ICP) data of severely head-injured patients. Direct computerization of physiological data from all four participating locations within the United States and transmission to a central data bank was found to be logistically complex and costly. A simple manual method for recording ICP, blood pressure, and concomitant ICP therapy at the bedside is described. The method documents the temporal course of these variables for the duration of monitoring. The importance of relating ICP to the therapy intensity level used for ICP management is emphasized. Concomitant analysis of the therapy intensity level is considered imperative in correlative patient studies. The methods described in this report have been in use among all four TCDB hospitals. Examples of ICP data retrieved from the TCDB are presented to illustrate the adequacy of the methods for assessing temporal trends. Of 1030 patients admitted to the TCDB, 654 severely head-injured patients had at least 4 hours of monitoring recorded; elevated ICP (> 20 mm Hg) was observed in 72% of these 654 patients.

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Feng, Zexi. "An efficient initial guess for the ICP method." Pattern Recognition Letters 125 (July 2019): 721–26. http://dx.doi.org/10.1016/j.patrec.2019.07.019.

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Sun, Wen, Ke Yang, and Longfei Xia. "Application of ICP-MS Method in Environmental Field." IOP Conference Series: Earth and Environmental Science 769, no. 2 (May 1, 2021): 022028. http://dx.doi.org/10.1088/1755-1315/769/2/022028.

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Moraes, Fabiano Moulin de, and Gisele Sampaio Silva. "Noninvasive intracranial pressure monitoring methods: a critical review." Arquivos de Neuro-Psiquiatria 79, no. 5 (May 2021): 437–46. http://dx.doi.org/10.1590/0004-282x-anp-2020-0300.

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ABSTRACT Background: Intracranial pressure (ICP) monitoring has been used for decades in management of various neurological conditions. The gold standard for measuring ICP is a ventricular catheter connected to an external strain gauge, which is an invasive system associated with a number of complications. Despite its limitations, no noninvasive ICP monitoring (niICP) method fulfilling the technical requirements for replacing invasive techniques has yet been developed, not even in cases requiring only ICP monitoring without cerebrospinal fluid (CSF) drainage. Objectives: Here, we review the current methods for niICP monitoring. Methods: The different methods and approaches were grouped according to the mechanism used for detecting elevated ICP or its associated consequences. Results: The main approaches reviewed here were: physical examination, brain imaging (magnetic resonance imaging, computed tomography), indirect ICP estimation techniques (fundoscopy, tympanic membrane displacement, skull elasticity, optic nerve sheath ultrasound), cerebral blood flow evaluation (transcranial Doppler, ophthalmic artery Doppler), metabolic changes measurements (near-infrared spectroscopy) and neurophysiological studies (electroencephalogram, visual evoked potential, otoacoustic emissions). Conclusion: In terms of accuracy, reliability and therapeutic options, intraventricular catheter systems still remain the gold standard method. However, with advances in technology, noninvasive monitoring methods have become more relevant. Further evidence is needed before noninvasive methods for ICP monitoring or estimation become a more widespread alternative to invasive techniques.

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Lenfeldt, Niklas, Nina Andersson, Aina Ågren-Wilsson, A. Tommy Bergenheim, Lars-Owe D. Koskinen, Anders Eklund, and Jan Malm. "Cerebrospinal fluid pulse pressure method: a possible substitute for the examination of B waves." Journal of Neurosurgery 101, no. 6 (December 2004): 944–50. http://dx.doi.org/10.3171/jns.2004.101.6.0944.

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Object. The appearance of numerous B waves during intracranial pressure (ICP) registration in patients with idiopathic adult hydrocephalus syndrome (IAHS) is considered to predict good outcome after shunt surgery. The aim of this study was to describe which physical parameters of the cerebrospinal fluid (CSF) system B-waves reflect and to find a method that could replace long-term B-wave analysis. Methods. Ten patients with IAHS were subjected to long-term registration of ICP and a lumbar constant-pressure infusion test. The B-wave presence, CSF outflow resistance (Rout), and relative pulse pressure coefficient (RPPC) were assessed using computerized analysis. The RPPC was introduced as a parameter reflecting the joint effect of elastance and pulsatory volume changes on ICP and was determined by relating ICP pulse amplitudes to mean ICP. Conclusions. The B-wave presence on ICP registration correlates strongly with RPPC (r = 0.91, p < 0.001, 10 patients) but not with CSF Rout. This correlation indicates that B waves—like RPPC—primarily reflect the ability of the CSF system to reallocate and store liquid rather than absorb it. The RPPC-assessing lumbar short-term CSF pulse pressure method could replace the intracranial long-term B-wave analysis.

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Eklund, Anders, Aina Ågren-Wilsson, Nina Andersson, A. Tommy Bergenheim, Lars-Owe D. Koskinen, and Jan Malm. "Two computerized methods used to analyze intracranial pressure B waves: comparison with traditional visual interpretation." Journal of Neurosurgery 94, no. 3 (March 2001): 392–96. http://dx.doi.org/10.3171/jns.2001.94.3.0392.

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Object. Slow and rhythmic oscillations in intracranial pressure (ICP), also known as B waves, have been claimed to be one of the best preoperative predictive factors in idiopathic adult hydrocephalus syndrome (IAHS). Definitions of B waves vary widely, and previously reported results must be treated with caution. The aims of the present study were to develop a definition of B waves, to develop a method to estimate the B-wave content in an ICP recording by using computer algorithms, and to validate these procedures by comparison with the traditional visual interpretation. Methods. In eight patients with IAHS, ICP was continuously monitored for approximately 20 hours. The ICP B-wave activity as a percentage of total monitoring time (B%) was estimated by using visual estimation according to the definition given by Lundberg, and also by using two computer algorithms (Methods I and II). In Method I each individual wave was classified as a B wave or not, whereas Method II was used to estimate the B-wave content by evaluating the B-wave power in 10-minute blocks of ICP recordings. Conclusions. The two computerized algorithms produced similar results. However, with the amplitude set to 1 mm Hg, Method I yielded the highest correlation with the visual analysis (r = 0.74). At least 5 hours of monitoring time was needed for an acceptable approximation of the B% in an overnight ICP recording. The advantages of using modern technology in the analysis of B-wave content of ICP are obvious and these methods should be used in future studies.

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Behmanesh, Bedjan, Matthias Setzer, Anika Noack, Marco Bartels, Johanna Quick-Weller, Volker Seifert, and Thomas M. Freiman. "Noninvasive epicutaneous transfontanelle intracranial pressure monitoring in children under the age of 1 year: a novel technique." Journal of Neurosurgery: Pediatrics 18, no. 3 (September 2016): 372–76. http://dx.doi.org/10.3171/2016.3.peds15701.

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Monitoring of intracranial pressure (ICP) may be indicated in children with traumatic brain injury, premature intraventricular hemorrhage, or hydrocephalus. The standard technique is either a direct measurement with invasive intracranial insertion of ICP probes or indirect noninvasive assessment using transfontanelle ultrasonography to measure blood flow. The authors have developed a new technique that allows noninvasive epicutaneous transfontanelle ICP measurement with standard ICP probes. They compared the ICP measurements obtained using the same type of standard probe used in 2 different ways in 5 infants (age < 1 year) undergoing surgery for craniosynostosis. The first ICP probe was implanted epidurally (providing control measurements) and the second probe was fixed epicutaneously on the skin over the reopened frontal fontanelle. ICP values were measured hourly for the first 24 hours after surgery and the values obtained with the 2 methods were compared using Bland-Altman 2-methods analysis. A total of 110 pairs of measurements were assessed. There was no significant difference between the ICPs measured using the epicutaneous transfontanelle method (mean 13.10 mm Hg, SEM 6.68 mm Hg) and the epidural measurements (mean 12.46 mm Hg, SEM 6.45 mm Hg; p = 0.4643). The results of this analysis indicate that epicutaneous transfontanelle measurement of ICP is a reliable method that allows noninvasive ICP monitoring in children under the age of 1 year. Such noninvasive ICP monitoring could be implemented in the therapy of children with traumatic brain injury or intraventricular hemorrhage or for screening children with elevated ICP without invasive intracranial implantation of ICP probes.

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Fan, Li Hua, Bo Liu, Bao Ling Xie, and Qi Chen. "Automatic Point Clouds Registration Method Based on Mesh Segmentation." Applied Mechanics and Materials 423-426 (September 2013): 2587–90. http://dx.doi.org/10.4028/www.scientific.net/amm.423-426.2587.

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This paper proposes an automatic point clouds registration method based on High-Speed Mesh Segmentation. The proposed method works fast for doing an initial registration and extracting point clouds region feature. First, the features of the point region are used for matching point cloud regions. Second, matched regions sets are classified for calculating transform matrix of initial registration. Based on the initial registration result the Iterative Closest Point (ICP) algorithm which had been used for accuracy registration to composite point cloud pairs will be applied. The proposed registration approach is able to do automatic registration without any assumptions about their initial positions, and avoid the problems of traditional ICP in bad initial estimate. The proposed method plus with ICP algorithm provides an efficient 3D model for computer-aided engineering and computer-aided design.

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Shi, Yi Ni, Kai Pei, Yin Feng Zhao, Yun Tan, Zhen Tai, Lin Zhang, and Yan Qiu Ji. "Impurity Detection Method for High-Purity BCl₃." Materials Science Forum 815 (March 2015): 76–79. http://dx.doi.org/10.4028/www.scientific.net/msf.815.76.

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A method for detecting impurities in high purity BCl3 was described in the present work. GC, ICP-MS, FTIR and colorimetric method were applied to analyze high-purity BCl3. The quantitative results of the impurities such as N2, CO, CO2 and Fe demonstrated that these methods had excellent repeatability (RSD<3%), reproducibility. The ICP-MS detection accuracy can achieve ppb limiter. The FTIR method provided opportunities for the determination of HCl, COCl2, which have difficulties in quantification with other method.

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Li, Xiaozhe, Chao Xiong, Kun Sun, Fang Fang, and Qingxian Zhang. "Optimization of ICP-OES’S parameters for uranium analysis of rock samples." Journal of the Korean Physical Society 78, no. 9 (March 31, 2021): 737–42. http://dx.doi.org/10.1007/s40042-021-00093-3.

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AbstractCurrently, the quantitative analysis methods for uranium that are widely used in laboratories, such as the volumetric method and inductively coupled plasma mass spectrometry (ICP-MS) cannot achieve low cost, simple operation, and little influence by other elements. The inductively coupled plasma optical emission spectrometer (ICP-OES) has a wide linear range, and high stability, and can be used to identify multiple elements simultaneously. However, when ICP-OES is used for quantitative analysis of uranium, the settings for the RF power, nebulizer flow, and pump rate can affect the analysis results. In this work, these parameters were carefully optimized for identifying uranium. Based on experiments, we selected two spectrum peaks 409.014 nm and 424.167 nm for quantitative analysis with the lowest interference. The optimal parameters obtained are atomizer flow rate of 0.75 L/min, a sample pumping rate of 1.6 mL/min, and a high-frequency power of 1400 W. Then we compared the accuracy of the volumetric method, ICP-MS method and ICP-OES method with the optimized parameter for analysis of experimental samples and references. The results showed that the ICP-OES with the optimized parameters proposed in this paper can be used to perform a convenient, quick, and efficient quantitative analysis of uranium in minerals.

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Zhang, Baoyue, Ziyi Huang, Huixue Song, Hyun Soo Kim, and Jaewon Park. "Wearable Intracranial Pressure Monitoring Sensor for Infants." Biosensors 11, no. 7 (June 29, 2021): 213. http://dx.doi.org/10.3390/bios11070213.

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Monitoring of intracranial pressure (ICP) is important for patients at risk of raised ICP, which may indicate developing diseases in brains that can lead to brain damage or even death. Monitoring ICP can be invaluable in the management of patients suffering from brain injury or hydrocephalus. To date, invasive measurements are still the standard method for monitoring ICP; however, these methods can not only cause bleeding or infection but are also very inconvenient to use, particularly for infants. Currently, none of the non-invasive methods can provide sufficient accuracy and ease of use while allowing continuous monitoring in routine clinical use at low cost. Here, we have developed a wearable, non-invasive ICP sensor that can be used like a band-aid. For the fabrication of the ICP sensor, a novel freeze casting method was developed to encapsulate the liquid metal microstructures within thin and flexible polymers. The final thickness of the ICP sensor demonstrated is 500 µm and can be further reduced. Three different designs of ICP sensors were tested under various pressure actuation conditions as well as different temperature environments, where the measured pressure changes were stable with the largest stability coefficient of variation being only CV = 0.0206. In addition, the sensor output values showed an extremely high linear correlation (R2 > 0.9990) with the applied pressures.

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Avan, Paul, Hervé Normand, Fabrice Giraudet, Grégory Gerenton, and Pierre Denise. "Noninvasive in-ear monitoring of intracranial pressure during microgravity in parabolic flights." Journal of Applied Physiology 125, no. 2 (August 1, 2018): 353–61. http://dx.doi.org/10.1152/japplphysiol.00032.2018.

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Among possible causes of visual impairment or headache experienced by astronauts in microgravity or postflight and that hamper their performance, elevated intracranial pressure (ICP) has been invoked but never measured for lack of noninvasive methods. The goal of this work was to test two noninvasive methods of ICP monitoring using in-ear detectors of ICP-dependent auditory responses, acoustic and electric, in acute microgravity afforded by parabolic flights. The devices detecting these responses were handheld tablets routinely used in otolaryngology for hearing diagnosis, which were customized for ICP extraction and serviceable by unskilled operators. These methods had been previously validated against invasive ICP measurements in neurosurgery patients. The two methods concurred in their estimation of ICP changes with microgravity, i.e., 11.0 ± 7.7 mmHg for the acoustic method ( n = 7 subjects with valid results out of 30, auditory responses being masked by excessive in-flight noise in 23 subjects) and 11.3 ± 10.6 mmHg for the electric method ( n = 10 subjects with valid results out of 10 tested despite the in-flight noise). These results agree with recent publications using invasive access to cerebrospinal fluid in parabolic flights and suggest that acute microgravity has a moderate average effect on ICP, similar to body tilt from upright to supine, yet with some subjects undergoing large effects whereas others seem immune. The electric in-ear method would be suitable for ICP monitoring in circumstances and with subjects such that invasive measurements are excluded. NEW & NOTEWORTHY In-ear detectors of intracranial pressure-dependent auditory responses allow intracranial pressure to be monitored noninvasively during acute microgravity. The average pressure increase during 20-s long sessions in microgravity is 11 mmHg, comparable with an effect of body tilt. However, intersubject variability is large, with subjects who repeatedly experience from nothing to twice the average effect. A systematic in-flight use would allow the relationship between space adaptation syndrome and ICP to be established or dismissed.

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Ittermann, Till, Simone Johner, Harald Below, Matthias Leiterer, Michael Thamm, Thomas Remer, and Henry Völzke. "Interlaboratory variability of urinary iodine measurements." Clinical Chemistry and Laboratory Medicine (CCLM) 56, no. 3 (February 23, 2018): 441–47. http://dx.doi.org/10.1515/cclm-2017-0580.

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AbstractBackground:The iodine status of populations is usually assessed by median urinary iodine concentrations (UIC) in population-based studies, but it is unclear to which extent UIC are comparable across different laboratories. The aim of our study was to investigate the variability of UIC measurements across three well-established German laboratories with long-term clinical-chemical expertise in iodine measurements and to compare these results to the gold standard inductively coupled plasma mass spectrometry (ICP-MS).Methods:UIC levels were measured from 303 urine samples derived from the “Dortmund Nutritional and Anthropometric Longitudinally Designed Study” and from volunteers of the University Medicine Greifswald at four different German laboratories. Three of these laboratories used Sandell-Kolthoff reaction with different digestion methods for UIC measurement (Lab1–Lab3), whereas one laboratory used ICP-MS as gold standard.Results:Median UIC levels were significantly different across the four laboratories (ICP-MS: 77 μg/L; Lab1: 69 μg/L; Lab2: 73 μg/L; Lab3: 111 μg/L). Linear regressions associating UIC levels of Lab1–Lab3 with UIC levels of ICP-MS showed intercepts significantly different from 0 and slopes significantly different from 1. Intraclass correlations (ICC) in comparison to ICP-MS were 0.91 for Lab1, 0.98 for Lab2, and 0.69 for Lab3. Using the digestion method of Lab2 in Lab3 improved the comparison of UIC levels of Lab3 with those from the ICP-MS (ICC=0.89).Conclusions:We have demonstrated larger interlaboratory variations across high-quality laboratories with long-lasting experience in iodine measurements indicating a relevant non-comparability of UIC measurements in iodine monitoring studies. Therefore, standardization of UIC measurements has to be expedited.

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Saitoh, Katsumi, Akihiro Fushimi, Yuji Fujitani, Kiyoshi Tanabe, Kei Sato, Akinori Takami, and Koichiro Sera. "Evaluation of elemental quantitative values of atmospheric aerosol samples by PIXE method." International Journal of PIXE 25, no. 01n02 (January 2015): 13–22. http://dx.doi.org/10.1142/s0129083515500023.

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In order to evaluate the quantitative values of atmospheric aerosol samples collected on filters, we investigated the effects of filter collection conditions (non-uniformity of collected particles) on analytical values and compared the quantitative values by means of PIXE and ICP-MS, using as the analytical sample PM2.5 collected on filters in a monitoring survey of atmospheric fine aerosol over the Kanto area of Japan in summer 2013. The results were as follows: (i) With respect to the uniformity of filter collection, differences in concentrations were seen for S and Cl as well as elements thought to originate in soil (Al, Si, Ti and Fe) depending on the analysis point, suggesting that collection of sulfate particles, chloride particles, and soil particles on filters was not uniform. (ii) According to a comparison of quantitative values yielded by PIXE and ICP-MS, ICP-MS values were lower than PIXE values for Mg, Al, Si, Ti and Fe, with Mg and Si being markedly lower. On the other hand, ICP-MS values were higher than PIXE values for Na, K, Ca and Zn. (iii) According to the results of measurement of NIST reference material and PM2.5 samples by means of PIXE and ICP-MS, Mg, Al, Si, Ca, Ti, Fe and Zn showed the same tendency. However, Na and K were opposite.

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Li, Hangyu, Jeroen C. Vink, and Faruk O. Alpak. "An Efficient Multiscale Method for the Simulation of In-situ Conversion Processes." SPE Journal 20, no. 03 (June 15, 2015): 579–93. http://dx.doi.org/10.2118/172498-pa.

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Summary Numerical modeling of the in-situ conversion process (ICP) is a challenging endeavor involving thermal multiphase flow, compositional pressure/volume/temperature (PVT) behavior, and chemical reactions that convert solid kerogen into light hydrocarbons, which are tightly coupled to temperature propagation. Our investigations of grid-resolution effects on the accuracy and performance of ICP simulations have demonstrated that ICP-simulation outcomes—specifically, chemical-reaction rates, kerogen-accumulation profiles, and oil-/gas-production rates, may exhibit relatively large errors on coarse grids. Coarse grids are attractive because they deliver favorable computational performance. We have developed a novel multiscale modeling method for simulating ICP that reduces numerical-modeling errors and reproduces fine-scale-simulation results on relatively coarse grids. The method uses a two-scale solution method, in which the reaction kinetics of the solids is solved locally on a fine-scale grid, with interpolated temperatures obtained from coarse-grid simulations of thermal flow and fluid transport. We demonstrate the accuracy and efficiency of our multiscale method with representative 1D models. It is shown that the method delivers accurate solutions for key ICP performance indicators with very little computational overhead compared with corresponding coarse-scale models. The robustness of the multiscale method has been verified over a number of physical-parameter ranges with a limited-scope sensitivity study. Numerical results show that the multiscale method consistently improves the simulation results and matches the fine-scale reference results closely.

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YING, SHIHUI, JIGEN PENG, SHAOYI DU, and HONG QIAO. "LIE GROUP FRAMEWORK OF ITERATIVE CLOSEST POINT ALGORITHM FOR n-D DATA REGISTRATION." International Journal of Pattern Recognition and Artificial Intelligence 23, no. 06 (September 2009): 1201–20. http://dx.doi.org/10.1142/s0218001409007533.

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The iterative closet point (ICP) method is a dominant method for data registration that has attracted extensive attention. In this paper, a unified mathematical model of ICP based on Lie group representation is established. Under the framework, the registration problem is formulated into an optimization problem over a certain Lie group. In order to simplify the model and to reduce the dimension of parameter space, the translation part of geometric transformation is eliminated by calibrating the centers of two data sets under registration. As a result, a fast algorithm by solving an iterative linear system is designed for the optimization problem on Lie groups. Moreover, PCA and ICA methods are jointly applied to estimate the initial registration to achieve the global minimum. Finally, several illustrations and comparison experiments are presented to test the performance of the proposed algorithm.

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Price, David Andrew, Andrzej Grzybowski, Jennifer Eikenberry, Ingrida Januleviciene, Alice Chandra Verticchio Vercellin, Sunu Mathew, Brent Siesky, and Alon Harris. "Review of non-invasive intracranial pressure measurement techniques for ophthalmology applications." British Journal of Ophthalmology 104, no. 7 (November 8, 2019): 887–92. http://dx.doi.org/10.1136/bjophthalmol-2019-314704.

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Assessment and monitoring of intracranial pressure (ICP) are important in the management of traumatic brain injury and other cerebral pathologies. In the eye, ICP elevation and depression both correlate with optic neuropathies, the former because of papilledema and the latter related to glaucoma. While the relationship between ICP elevation and papilledema is well established, the relationship between low ICP and glaucoma is still poorly understood. So far, ICP monitoring is performed invasively, but this entails risks including infection, spurring the study of non-invasive alternatives. We review 11 methods of non-invasive estimation of ICP including correlation to optic nerve sheath diameter, intraocular pressure, ophthalmodynamometry and two-depth transcranial Doppler of the ophthalmic artery. While none of these methods can fully replace invasive techniques, certain measures show great potential for specific applications. Although only used in small studies to date, a MRI based method known as MR-ICP, appears to be the best non-invasive technique for estimating ICP, with two-depth transcranial ultrasound and ophthalmodynamometry showing potential as well.

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Bingöl, M., G. Yentür, B. Er, and A. B. Öktem. "Determination of some heavy metal levels in soft drinks from Turkey using ICP/OES method." Czech Journal of Food Sciences 28, No. 3 (July 1, 2010): 213–16. http://dx.doi.org/10.17221/158/2008-cjfs.

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Total number of 104 canned soft drinks collected from several regions in Turkey were analysed. The purpose of this study was to determine the levels of heavy metals in the drinks commonly consumed in Turkey. Quantitative determination of heavy metals: arsenic, copper, zinc, cadmium, and lead in all samples was carried out by ICP-OES (Inductively Coupled Plasma-Optical Emission Spectrometry) method. The mean levels (± SE) of arsenic, copper, zinc, cadmium, and lead were found to be 0.037 ± 0.002 mg/kg, 0.070 ± 0.009 mg/kg, 0.143 ± 0.012 mg/kg, 0.005 ± 0.0003 mg/kg, and 0.029 ± 0.002 mg/kg, respectively, in soft drinks. Our data revealed that arsenic, copper, zinc, cadmium, and lead mean levels found in all soft drinks, collected from several regions in Turkey, were within the Turkish Food Codex (TFC) values.

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Schmidt, Bernhard, and Jürgen Klingelhöfer. "Clinical applications of a non-invasive ICP monitoring method." European Journal of Ultrasound 16, no. 1-2 (November 2002): 37–45. http://dx.doi.org/10.1016/s0929-8266(02)00044-7.

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孙, 秀萍. "Determine Three Elements in Ferroniobium with ICP-AES Method." Advances in Analytical Chemistry 04, no. 02 (2014): 20–25. http://dx.doi.org/10.12677/aac.2014.42004.

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Spaulding, Nicole E., Sharon B. Sneed, Michael J. Handley, Pascal Bohleber, Andrei V. Kurbatov, Nicholas J. Pearce, Tobias Erhardt, and Paul A. Mayewski. "A New Multielement Method for LA-ICP-MS Data Acquisition from Glacier Ice Cores." Environmental Science & Technology 51, no. 22 (November 9, 2017): 13282–87. http://dx.doi.org/10.1021/acs.est.7b03950.

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Bohleber, Pascal, Marco Roman, Martin Šala, Barbara Delmonte, Barbara Stenni, and Carlo Barbante. "Two-dimensional impurity imaging in deep Antarctic ice cores: snapshots of three climatic periods and implications for high-resolution signal interpretation." Cryosphere 15, no. 7 (July 29, 2021): 3523–38. http://dx.doi.org/10.5194/tc-15-3523-2021.

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Abstract. Due to its micrometer-scale resolution and inherently micro-destructive nature, laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is particularly suited to exploring the thin and closely spaced layers in the oldest sections of polar ice cores. Recent adaptions to the LA-ICP-MS instrumentation mean we have faster washout times allowing state-of-the-art 2-D imaging of an ice core. This new method has great potential especially when applied to the localization of impurities on the ice sample, something that is crucial, to avoiding misinterpretation of the ultra-fine-resolution signals. Here we present the first results of the application of LA-ICP-MS elemental imaging to the analysis of selected glacial and interglacial samples from the Talos Dome and EPICA Dome C ice cores from central Antarctica. The localization of impurities from both marine and terrestrial sources is discussed, with special emphasis on observing a connection with the network of grain boundaries and differences between different climatic periods. Scale-dependent image analysis shows that the spatial significance of a single line profile along the main core axis increases systematically as the imprint of the grain boundaries weakens. It is demonstrated how instrumental settings can be adapted to suit the purpose of the analysis, i.e., by either employing LA-ICP-MS to study the interplay between impurities and the ice microstructure or to investigate the extremely thin climate proxy signals in deep polar ice.

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D’Antona, L., L. Craven, D. Thompson, S. Sennik, J. Ramos, L. Thorne, K. Toma, and D. Watkins. "TM3-3 Correlation of lumbar puncture opening pressure with 24 hours intraparenchymal ICP monitoring: the effects of position on ICP." Journal of Neurology, Neurosurgery & Psychiatry 90, no. 3 (February 14, 2019): e15.3-e16. http://dx.doi.org/10.1136/jnnp-2019-abn.49.

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ObjectivesLumbar Puncture opening pressure in lateral decubitus has been considered the gold standard method of intracranial pressure (ICP) measurement for many years. The use of continuous intraparenchymal ICP monitoring is more recent and there is no consensus regarding what can be considered normal ICP with this method of measurement. A conversion factor between lumbar puncture opening pressure and 24 hours ICP monitoring could provide a better insight on the interpretation of ICP. This study investigates the differences between 24 hours ICP and ICP in lumbar puncture position.DesignSingle centre prospective observational study.SubjectsFifty-four patients (42F:12M, mean age 38±12 years) were included.MethodsPatients investigated with 24 hours ICP monitoring who underwent a short exercise battery during the monitoring period were included. The exercise battery was standardised; patients were asked to stay in a supine, sitting, standing and lumbar puncture position for 2 min each.Mean ICP and pulse amplitude were calculated for each position.ResultsThe mean 24 hours ICP was 4.9 mmHg (±6.9 SD) and the mean ICP in lumbar puncture position was 14.1 mmHg (±8.9 SD). The average increase in lumbar puncture position was 9.1 mmHg (±5.9 SD). Patients with normal lumbar puncture position ICP (<12 mmHg) had an average 24 hours ICP of 1.4 mmHg (±2.81 SD).ConclusionsOur results suggest that ICP measured in lumbar puncture position is on average 9.1 mmHg higher than 24 hours ICP results. Larger studies will be needed to confirm these findings.

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Tai, Kiyoshi, Jae Hyun Park, Katsuaki Mishima, and Hitoshi Hotokezaka. "Using Superimposition of 3-Dimensional Cone-Beam Computed Tomography Images with Surface-Based Registration in Growing Patients." Journal of Clinical Pediatric Dentistry 34, no. 4 (July 1, 2010): 361–67. http://dx.doi.org/10.17796/jcpd.34.4.w8n6321878105431.

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Objective: The purpose of this research was to evaluate a new method of superimposing detailed cone-beam computed tomography (CBCT) images. Materials and Methods: This study used 5 different software programs to transform the digital imaging and communication in medicine (DICOM) data from CBCT image into polygon data. The data conversion errors from different software programs were verified by the polyacetal ball test and the dry skull test. The iterative closest point (ICP) method was used for precise superimposition. To evaluate changes related to growth, three different domains were superimposed in order to investigate appropriate areas for evaluation by the ICP method. Results: The ICP method in the cranial base(excluding the peripheral zone) was indicated as the most reliable surface in this research. There were no measurement errors in converting the image data between software programs. Conclusion: The ICP method in the cranial base (excluding the peripheral zone) is one of the most accurate methods for superimposition when the mandibular rotation or displacement has not occurred during growth or treatment. This 3-dimesional(3D) superimposition technique can be used for a valid and reproducible assessment of treatment outcomes for growing subjects. This method is considered to be of clinical value because of the manageability and 3D accuracy of the data comparison with multi planar reconstruction (MPR) images.

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Vik, Anne, Torbjørn Nag, Oddrun Anita Fredriksli, Toril Skandsen, Kent Gøran Moen, Kari Schirmer-Mikalsen, and Geoffrey T. Manley. "Relationship of “dose” of intracranial hypertension to outcome in severe traumatic brain injury." Journal of Neurosurgery 109, no. 4 (October 2008): 678–84. http://dx.doi.org/10.3171/jns/2008/109/10/0678.

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Object It has recently been suggested that the degree of intracranial pressure (ICP) above the treatment goal can be estimated by the area under the curve (AUC) of ICP versus time in patients with severe traumatic brain injury (TBI). The objective of this study was to determine whether the calculated “ICP dose”—the ICP AUC—is related to mortality rate, outcome, and Marshall CT classification. Methods Of 135 patients (age range 1–82 years) with severe TBI treated during a 5-year period at the authors' institution, 113 patients underwent ICP monitoring (84%). Ninety-three patients with a monitoring time > 24 hours were included for analysis of ICP AUC calculated using the trapezoidal method. Computed tomography scans were assessed according to the Marshall TBI classification. Patients with Glasgow Outcome Scale scores at 6 months and > 3 years were separated into 2 groups based on outcome. Results Sixty patients (65%) had ICP values > 20 mm Hg, and 12 (13%) developed severe intracranial hypertension and died secondary to herniation. A multiple regression analysis adjusting for Glasgow Coma Scale score, age, pupillary abnormalities and Injury Severity Scale score demonstrated that the ICP AUC was a significant predictor of poor outcome at 6 months (p = 0.034) and of death (p = 0.035). However, it did not predict long-term outcome (p = 0.157). The ICP AUC was significantly higher in patients with Marshall head injury Categories 3 and 4 (24 patients) than in those with Category 2 (23 patients, p = 0.025) and Category 5 (46 patients, p = 0.021) TBIs using the worst CT scan obtained. Conclusions The authors found a significant relationship between the dose of ICP, the worst Marshall CT score, and patient outcome, suggesting that the AUC method may be useful in refining and improving the treatment of ICP in patients with TBI.

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Yang, Jianjian, Chao Wang, Wenjie Luo, Yuchen Zhang, Boshen Chang, and Miao Wu. "Research on Point Cloud Registering Method of Tunneling Roadway Based on 3D NDT-ICP Algorithm." Sensors 21, no. 13 (June 29, 2021): 4448. http://dx.doi.org/10.3390/s21134448.

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In order to meet the needs of intelligent perception of the driving environment, a point cloud registering method based on 3D NDT-ICP algorithm is proposed to improve the modeling accuracy of tunneling roadway environments. Firstly, Voxel Grid filtering method is used to preprocess the point cloud of tunneling roadways to maintain the overall structure of the point cloud and reduce the number of point clouds. After that, the 3D NDT algorithm is used to solve the coordinate transformation of the point cloud in the tunneling roadway and the cell resolution of the algorithm is optimized according to the environmental features of the tunneling roadway. Finally, a kd-tree is introduced into the ICP algorithm for point pair search, and the Gauss–Newton method is used to optimize the solution of nonlinear objective function of the algorithm to complete accurate registering of tunneling roadway point clouds. The experimental results show that the 3D NDT algorithm can meet the resolution requirement when the cell resolution is set to 0.5 m under the condition of processing the point cloud with the environmental features of tunneling roadways. At this time, the registering time is the shortest. Compared with the NDT algorithm, ICP algorithm and traditional 3D NDT-ICP algorithm, the registering speed of the 3D NDT-ICP algorithm proposed in this paper is obviously improved and the registering error is smaller.

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Garbarino, J. R., B. E. Jones, G. P. Stein, W. T. Belser, and H. E. Taylor. "Statistical Evaluation of an Inductively Coupled Plasma Atomic Emission Spectrometric Method for Routine Water Quality Testing." Applied Spectroscopy 39, no. 3 (May 1985): 535–41. http://dx.doi.org/10.1366/0003702854248458.

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In an interlaboratory test, inductively coupled plasma atomic emission spectrometry (ICP-AES) was compared with flame atomic absorption spectrometry and molecular absorption spectrophotometry for the determination of 17 major and trace elements in 100 filtered natural water samples. No unacceptable biases were detected. The analysis precision of ICP-AES was found to be equal to or better than alternative methods. Known-addition recovery experiments demonstrated that the ICP-AES determinations are accurate to between ±2 and ±10 percent; four-fifths of the tests yielded average recoveries of 95–105 percent, with an average relative standard deviation of about 5 percent.

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Lee, Sung-Bae, Yong-Soon Kim, Yong-Hoon Lee, Byung-Joon Ahn, Nam-Soo Kim, Byung-Kook Lee, and Ho-Sang Shin. "Validation of ICP-MS method for trace level analysis of Pb in plasma." Analytical Science and Technology 28, no. 5 (October 25, 2015): 309–16. http://dx.doi.org/10.5806/ast.2015.28.5.309.

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Bershad, Eric M., Mian Z. Urfy, Alina Pechacek, Mary McGrath, Eusebia Calvillo, Nicholas J. Horton, and Susan E. Voss. "Intracranial Pressure Modulates Distortion Product Otoacoustic Emissions." Neurosurgery 75, no. 4 (May 27, 2014): 445–55. http://dx.doi.org/10.1227/neu.0000000000000449.

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Abstract BACKGROUND: There is an important need to develop a noninvasive method for assessing intracranial pressure (ICP). We report a novel approach for monitoring ICP using cochlear-derived distortion product otoacoustic emissions (DPOAEs), which are affected by ICP. OBJECTIVE: We hypothesized that changes in ICP may be reflected by altered DPOAE responses via an associated change in perilymphatic pressure. METHODS: We measured the ICP and DPOAEs (magnitude and phase angle) during opening and closing in 20 patients undergoing lumbar puncture. RESULTS: We collected data on 18 patients and grouped them based on small (<4 mm Hg), medium (5–11 mm Hg), or large (≥15 mm Hg) ICP changes. A permutation test was applied in each group to determine whether changes in DPOAEs differed from zero when ICP changed. We report significant changes in the DPOAE magnitudes and angles, respectively, for the group with the largest ICP changes and no changes for the group with the smallest changes; the group with medium changes had variable DPOAE changes. CONCLUSION: We report, for the first time, systematic changes in DPOAE magnitudes and phase in response to acute ICP changes. Future studies are warranted to further develop this new approach.

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Saldivar, Emilio E., and Richard J. Jardine. "Application of an effective stress design method to concrete piles driven in Mexico City clay." Canadian Geotechnical Journal 42, no. 6 (December 1, 2005): 1495–508. http://dx.doi.org/10.1139/t05-062.

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Piled foundations are used widely in the lake clay zones of Mexico City, with “friction” piles being driven into soft diatomaceous clay deposits that show an extraordinary range of mechanical properties. The paper assesses the applicability of the Imperial College pile (ICP) design method to the concrete piles driven in these deposits. After the ICP methodology and Mexico City ground conditions are reviewed, an experimental study is reported of the key soil properties required for the ICP procedures: yield stress ratio, unit weight, interface friction angle (δ), sensitivity (St), and intrinsic properties. The new data are then applied to a specially assembled database of static pile load tests from different Mexico City clay locations, with allowance being made for site-specific details and local installation procedures. A quantitative assessment shows that the ICP methodology is free from significant bias and leads to more reliable estimates of static capacity than the total stress (α) design method routinely used in Mexico City.Key words: validation, database, static axial pile capacity, driven friction pile, effective stress design, silty clay.

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Yang, Wei Min, Rhonda L. Boles, and Thomas P. Mawhinney. "Determination of Phosphorus in Fertilizers by Inductively Coupled Plasma Atomic Emission Spectrometry." Journal of AOAC INTERNATIONAL 85, no. 6 (November 1, 2002): 1241–46. http://dx.doi.org/10.1093/jaoac/85.6.1241.

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Abstract An inductively coupled plasma atomic emission spectrometry (ICP-AES) method was developed for the determination of phosphorus in fertilizers. Total phosphorus, direct extraction available phosphorus (EDTA), and water-soluble phosphorus, reported as phosphorus pentoxide (P2O5), in 15 Magruder check fertilizers were measured by ICP-AES, and the results were compared with those obtained by the AOAC official method. Five analytical wavelengths of phosphorus, 177.499, 178.287, 213.618, 214.914, and 253.565 nm, were tested for the determination of phosphorus in fertilizers, and their detection limits were obtained. Acid effects of perchloric acid and possible matrix effects of aluminum, calcium, magnesium, potassium, and sodium were negligible for phosphorus determination. Wavelength 213.618 nm was the best analytical wavelength for phosphorus determination by all 3 sample preparation methods for the selected Magruder fertilizers. The results demonstrated that the accuracy and precision of the ICP-AES method were comparable with those of the official methods.

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Journal articles on the topic 'ICP Method'

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