scholarly journals Simple Ways to Estimate Meningioma Volume: Can ABC- and SH-Derived Methods Be Used in Clinical Practice Reliably?

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Dongdong Xiao ◽  
Jun Liu ◽  
Tingting Hu ◽  
Burkutally Mohammad Shah Nayaz ◽  
Xiaobing Jiang ◽  
...  
Keyword(s):  
Small Volume ◽  
Estimation Error ◽  
Rank Correlation ◽  
Correlation Coefficients ◽  
Volume Estimation ◽  
Tumor Diameter ◽  
Estimation Errors ◽  
Suitable Parameter ◽  
Maximum Tumor Diameter ◽  
Data Points

Background. There is a clinical demand for rapid estimation of meningioma volumes. Our objective was to assess the accuracy of three ABC-derived and three SH-derived formula methods on volume estimation of meningiomas. Methods. The study group comprised 678 patients treated at our department for histopathologically proven intracranial meningiomas. For each patient, tumor volumes were independently measured using six formula methods as well as planimetry. Maximum tumor diameter and ellipsoidity were also recorded. Volumes were compared using descriptive statistics, correlation analysis, and consistency analysis. Results. Among all methods assessed, 2/3SH and 1/2ABC outperformed the others. No significant differences were found between volumes obtained by the two methods and those of planimetry ( p > 0.05 ). Spearman rank-correlation coefficients (rs) were 0.99 for both methods ( p < 0.01 ), and ICC were 0.99 and 0.98, respectively. In Bland-Altman plot, most data points lay inside the limit of agreement. Overall, 2/3SH overestimated tumor volumes by 1.29%, and estimation errors in 93.66% cases were within 20%; 1/2ABC overestimated tumor volumes by 5.36%, and estimation errors in 93.51% cases were within 30%. The performance of 2/3SH and 1/2ABC in small-volume meningiomas was slightly worse, especially for 1/2ABC. Correlations between ellipsoidity and percentage errors of 2/3SH and 1/2ABC were weak (rs = −0.06 and −0.24, respectively). Despite a significant correlation between maximum tumor diameter and planimetric volume (rs = −0.96), volumes could vary significantly for a given diameter. Conclusions. Formula methods 2/3SH and 1/2ABC can estimate meningioma volumes with decent accuracy. Compared with the 1/2ABC method, the 2/3SH method showed slightly better performance, especially in small-volume meningiomas. Ellipsoidity is not a suitable parameter to predict estimation error, and maximum tumor diameter is not a reliable surrogate for actual meningioma volume.

scholarly journals Large volume re-irradiation with bevacizumab is a feasible salvage option for patients with refractory high-grade glioma

2014 ◽  
Vol 2 (1) ◽  
pp. 48-53 ◽  
Author(s):  
Michael Back ◽  
Cecelia E. Gzell ◽  
Marina Kastelan ◽  
Linxin Guo ◽  
Helen R. Wheeler
Keyword(s):  
Median Survival ◽  
Large Volume ◽  
Small Volume ◽  
Tumor Volume ◽  
High Grade Glioma ◽  
Target Volume ◽  
Tumor Diameter ◽  
High Grade ◽  
Kaplan Meier ◽  
Maximum Tumor Diameter

AbstractBackgroundClinical studies of re-irradiation (ReRT) for relapsed high-grade glioma (HGG) have generally reported the use of small volume ReRT techniques such as stereotactic radiosurgery in selected patients with isolated focal relapse. This study reports the outcome with large-volume ReRT to manage the more common mescenario of extensive diffuse relapse of HGG.MethodsAll HGG patients managed with an overlapping second course of radiation therapy (RT) for refractory progression of HGG between October 2009 and April 2013 were included. ReRT was initially used with bevacizumab (BEV), then used when disease was refractory to BEV, and finally used upfront with BEV-naïve patients. Tumor volume (GTV) and specific RT dosimetry factors, including the target volume treated (PTV), and cumulative RT dose maximum (Dmax), were analyzed. Median survival post ReRT was calculated using the Kaplan-Meier method and SPPS v19 software.ResultsEighteen HGG participants with refractory, bulky contrast-enhancing disease received ReRT. Thirteen participants had a maximum tumor diameter &gt;5 cm, and median GTV was 54 cm3. Seven participants had BEV-refractory disease, and 8 participants were BEV naïve. ReRT dose was 35–40 Gy in 15 fractions; median PTV was 133 cm3, and median Dmax was 98.2 Gy. Median survival post ReRT for all participants was 8 months (95%CI, 5.8–10.2 months); with 10 months and 3 months for the BEV-naïve and BEV-refractory participants, respectively (P = .024). Two early participants, who were managed without BEV, were later salvaged with BEV, including one who required craniotomy for radiation necrosis at 6 weeks post RT. No other significant morbidity was reported.ConclusionReRT combined with BEV is a feasible salvage treatment option for diffuse refractory HGG.

scholarly journals A Preliminary Study on Dependence of Mercury Distribution on the Degree of Coalification in Ningwu Coalfield, Shanxi, China

Energies ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3119
Author(s):  
Yinjiao Su ◽  
Xuan Liu ◽  
Yang Teng ◽  
Kai Zhang
Keyword(s):  
Linear Correlation ◽  
Bituminous Coal ◽  
Rank Correlation ◽  
Correlation Coefficients ◽  
Chemical Extraction ◽  
Mercury Distribution ◽  
Sequential Chemical Extraction ◽  
Average Proportion ◽  
Total Proportion ◽  
The Relationship

Mercury (Hg) is a toxic trace element emitted from coal conversion and utilization. Samples with different coal ranks and gangue from Ningwu Coalfield are selected and investigated in this study. For understanding dependence of mercury distribution characteristics on coalification degree, Pearson regression analysis coupled with Spearman rank correlation is employed to explore the relationship between mercury and sulfur, mercury and ash in coal, and sequential chemical extraction method is adopted to recognize the Hg speciation in the samples of coal and gangue. The measured results show that Hg is positively related to total sulfur content in coal and the affinity of Hg to different sulfur forms varies with the coalification degree. Organic sulfur has the biggest impact on Hg in peat, which becomes weak with increasing the coalification degree from lignite to bituminous coal. Sulfate sulfur is only related to Hg in peat or lignite as little content in coal. However, the Pearson linear correlation coefficients of Hg and pyritic sulfur are relatively high with 0.479 for lignite, 0.709 for sub-bituminous coal and 0.887 for bituminous coal. Hg is also related to ash content in coal, whose Pearson linear correlation coefficients are 0.504, 0.774 and 0.827 respectively, in lignite, sub-bituminous coal and bituminous coal. Furthermore, Hg distribution is directly depended on own speciation in coal. The total proportion of F2 + F3 + F4 is increased from 41.5% in peat to 87.4% in bituminous coal, but the average proportion of F5 is decreased from 56.8% in peat to 12.4% in bituminous coal. The above findings imply that both Hg and sulfur enrich in coal largely due to the migration from organic state to inorganic state with the increase of coalification degree in Ningwu Coalfield.

scholarly journals Workflow to build a continuous static elastic moduli profile from the drilling data using artificial intelligence techniques

2021 ◽  
Author(s):  
Osama Siddig ◽  
Salaheldin Elkatatny
Keyword(s):  
Young’S Modulus ◽  
Elastic Moduli ◽  
Young's Modulus ◽  
Correlation Coefficients ◽  
Wellbore Stability ◽  
Machine Learning Techniques ◽  
Support Vector ◽  
Ann Model ◽  
Weight On Bit ◽  
Data Points

AbstractRock mechanical properties play a crucial role in fracturing design, wellbore stability and in situ stresses estimation. Conventionally, there are two ways to estimate Young’s modulus, either by conducting compressional tests on core plug samples or by calculating it from well log parameters. The first method is costly, time-consuming and does not provide a continuous profile. In contrast, the second method provides a continuous profile, however, it requires the availability of acoustic velocities and usually gives estimations that differ from the experimental ones. In this paper, a different approach is proposed based on the drilling operational data such as weight on bit and penetration rate. To investigate this approach, two machine learning techniques were used, artificial neural network (ANN) and support vector machine (SVM). A total of 2288 data points were employed to develop the model, while another 1667 hidden data points were used later to validate the built models. These data cover different types of formations carbonate, sandstone and shale. The two methods used yielded a good match between the measured and predicted Young’s modulus with correlation coefficients above 0.90, and average absolute percentage errors were less than 15%. For instance, the correlation coefficients for ANN ranged between 0.92 and 0.97 for the training and testing data, respectively. A new empirical correlation was developed based on the optimized ANN model that can be used with different datasets. According to these results, the estimation of elastic moduli from drilling parameters is promising and this approach could be investigated for other rock mechanical parameters.

Assessment of 2D ultrasound fluid volume estimation accuracy in different shaped objects: an in vitro study

2019 ◽  
Vol 61 (2) ◽  
pp. 253-259
Author(s):  
Iroshani Kodikara ◽  
Iroshini Abeysekara ◽  
Dhanusha Gamage ◽  
Isurani Ilayperuma
Keyword(s):  
Estimation Error ◽  
In Vitro Study ◽  
High Accuracy ◽  
Volume Estimation ◽  
Estimation Accuracy ◽  
Rater Agreement ◽  
Actual Volume ◽  
2D Ultrasound ◽  
One Way Anova

Background Volume estimation of organs using two-dimensional (2D) ultrasonography is frequently warranted. Considering the influence of estimated volume on patient management, maintenance of its high accuracy is empirical. However, data are scarce regarding the accuracy of estimated volume of non-globular shaped objects of different volumes. Purpose To evaluate the volume estimation accuracy of different shaped and sized objects using high-end 2D ultrasound scanners. Material and Methods Globular (n=5); non-globular elongated (n=5), and non-globular near-spherical shaped (n=4) hollow plastic objects were scanned to estimate the volumes; actual volumes were compared with estimated volumes. T-test and one-way ANOVA were used to compare means; P<0.05 was considered significant. Results The actual volumes of the objects were in the range of 10–445 mL; estimated volumes ranged from 6.4–425 mL ( P=0.067). The estimated volume was lower than the actual volume; such volume underestimation was marked for non-globular elongated objects. Regardless of the scanner, the highest volume estimation error was for non-globular elongated objects (<40%) followed by non-globular near-spherical shaped objects (<23.88%); the lowest was for globular objects (<3.6%). Irrespective of the shape or the volume of the object, volume estimation difference among the scanners was not significant: globular (F=0.430, P=0.66); non-globular elongated (F=3.69, P=0.064); and non-globular near-spherical (F=4.00, P=0.06). A good inter-rater agreement (R=0.99, P<0.001) and a good correlation between actual versus estimated volumes (R=0.98, P<0.001) were noted. Conclusion The 2D ultrasonography can be recommended for volume estimation purposes of different shaped and different sized objects, regardless the type of the high-end scanner used.

scholarly journals Regional robust secure precise wireless transmission design for multi-user UAV broadcasting system

2020 ◽  
Vol 2020 (1) ◽  
Author(s):  
Tong Shen ◽  
Tingting Liu ◽  
Yan Lin ◽  
Yongpeng Wu ◽  
Feng Shu ◽  
...  
Keyword(s):  
Estimation Error ◽  
Wireless Transmission ◽  
Artificial Noise ◽  
Target Area ◽  
Secrecy Rate ◽  
Estimation Errors ◽  
Transmission Design ◽  
Broadcasting System ◽  
Aerial Vehicle ◽  
Noise Ratio

Abstract In this paper, two regional robust secure precise wireless transmission (SPWT) schemes for multi-user unmanned aerial vehicle (UAV), (1)regional signal-to-leakage-and-noise ratio (SLNR) and artificial-noise-to-leakage-and-noise ratio (ANLNR) (R-SLNR-ANLNR) maximization and (2) point SLNR and ANLNR (P-SLNR-ANLNR) maximization, are proposed to tackle with the estimation errors of the target users’ location. In the SPWT system, the estimation error for SPWT cannot be ignored. However, the conventional robust methods in secure wireless communications optimize the beamforming vector in the desired positions only in statistical means and cannot guarantee the security for each symbol. The proposed regional robust schemes are designed for optimizing the secrecy performance in the whole error region around the estimated location. Specifically, with the known maximal estimation error, we define the target region and wiretap region. Then, we design an optimal beamforming vector and an artificial noise projection matrix, which achieve the confidential signal in the target area having the maximal power while only few signal power is conserved in the potential wiretap region. Instead of considering the statistical distributions of the estimated errors into optimization, we optimize the SLNR and ANLNR of the whole target area, which significantly decreases the complexity. Moreover, the proposed schemes can ensure that the desired users are located in the optimized region, which are more practical than the conventional methods. Simulation results show that our proposed regional robust SPWT design is capable of substantially improving the secrecy rate compared to the conventional non-robust method. The P-SLNR-ANLNR maximization-based method has the comparable secrecy performance with lower complexity than that of the R-SLNR-ANLNR maximization-based method.

Significance of Platelet and AFP Levels and Liver Function Parameters for HCC Size and Survival

2014 ◽  
Vol 29 (3) ◽  
pp. 215-223 ◽  
Author(s):  
Brian I. Carr ◽  
Vito Guerra ◽  
Edoardo G. Giannini ◽  
Fabio Farinati ◽  
Francesca Ciccarese ◽  
...  
Keyword(s):  
Tumor Size ◽  
Blood Platelet ◽  
Tumor Diameter ◽  
Proportional Hazard ◽  
Gamma Glutamyl Transpeptidase ◽  
Vein Thrombosis ◽  
Risk Of Death ◽  
Cox Proportional Hazard ◽  
Maximum Tumor Diameter ◽  
Glutamyl Transpeptidase

Background Hepatocellular carcinoma (HCC) is a heterogeneous disease with both tumor and liver factors being involved. Aims To investigate HCC clinical phenotypes and factors related to HCC size. Methods Prospectively-collected HCC patients' data from a large Italian database were arranged according to the maximum tumor diameter (MTD) and divided into tumor size terciles, which were then compared in terms of several common clinical parameters and patients' survival. Results An higer MTD tercile was significantly associated with increased blood alpha-fetoprotein (AFP), gamma-glutamyl transpeptidase (GGTP), and platelet levels. Patients with higher platelet levels had larger tumors and higher GGTP levels, with lower bilirubin levels. However, patients with the highest AFP levels had larger tumors and higher bilirubin levels, reflecting an aggressive biology. AFP correlation analysis revealed the existence of 2 different groups of patients: those with higher and with lower AFP levels, each with different patient and tumor characteristics. The Cox proportional-hazard model showed that a higher risk of death was correlated with GGTP and bilirubin levels, tumor size and number, and portal vein thrombosis (PVT), but not with AFP or platelet levels. Conclusions An increased tumor size was associated with increased blood platelet counts, AFP and GGTP levels. Platelet and AFP levels were important indicators of tumor size, but not of survival.

scholarly journals Comparison of a picture-sort food-frequency questionnaire with 24-hour dietary recalls in an elderly Utah population

2001 ◽  
Vol 4 (5) ◽  
pp. 961-970 ◽  
Author(s):  
Heidi J Wengreen ◽  
Ronald G Munger ◽  
Siew Sun Wong ◽  
Nancy A West ◽  
Richard Cutler
Keyword(s):  
Food Frequency Questionnaire ◽  
Dietary Assessment ◽  
Rank Correlation ◽  
Correlation Coefficients ◽  
Assessment Method ◽  
Impaired Hearing ◽  
Low Literacy ◽  
Food Frequency ◽  
Dietary Recall ◽  
Memory Skill

AbstractObjective:To evaluate the 137-item Utah Picture-sort Food-frequency Questionnaire (FFQ) in the measurement of usual dietary intake in older adults.Design:The picture-sort FFQ was administered at baseline and again one year later. Three seasonal 24-hour dietary recall interviews were collected during the year between the two FFQs. Mean nutrient intakes were compared between methods and between administrations of the FFQ.Setting:The FFQ interviews were administered in respondents' homes or care-centres. The 24-hour diet recalls were conducted by telephone interview on random days of the week.Subjects:Two-hundred-and-eight men and women aged 55–84 years were recruited by random sample of controls from a case–control study of nutrition and bone health in Utah.Results:After adjustment for total energy intake, median Spearman rank correlation coefficients between the two picture-sort FFQs were 0.69 for men aged ≤69 years, 0.66 for men aged >69 years; and 0.68 for women aged ≤69 years, 0.67 for women aged >69 years. Median correlation coefficients between methods were 0.50 for men ≤69 years old, 0.52 for men >69 years old; 0.55 for women ≤69 years old, 0.46 for women >69 years old.Conclusions:We report intake correlations between methods and administrations comparable to those reported in the literature for traditional paper-and-pencil FFQs and one other picture-sort method of FFQ. This dietary assessment method may improve ease and accuracy of response in this and other populations with low literacy levels, poor memory skill, impaired hearing, or poor vision.

scholarly journals Concurrent validity of the Sensory Organization Test measures in unilateral transtibial amputees

2012 ◽  
Vol 37 (1) ◽  
pp. 65-69 ◽  
Author(s):  
Prasath Jayakaran ◽  
Gillian M Johnson ◽  
S John Sullivan
Keyword(s):  
Concurrent Validity ◽  
Rank Correlation ◽  
Correlation Coefficients ◽  
Sensory Organization Test ◽  
Spearman’S Rank Correlation ◽  
Sensory Organization ◽  
Clinical Measures ◽  
Transtibial Amputees ◽  
Lower Limb Amputees ◽  
Strategy Score

Background and Aim: The physical asymmetries associated with a prosthesis raises the question of validity of the Sensory Organization Test (SOT) measures (equilibrium score (ES) and strategy score (SS)) in lower limb amputees. This study explores the validity of these measures in transtibial amputees by correlating with their corresponding centre of pressure (COP) excursion/velocity measures. Technique: Fifteen transtibial amputees (69.5 ± 6.5 years) completed three trials for each of the six SOT conditions. Discussion: The Spearman’s rank correlation coefficients between ESs and global COP excursion/velocity measures ranged from 0.52 to 0.71 for Conditions 1, 4 and 5, 0.79 to 0.85 for Conditions 2 and 3, and 0.39 to 0.43 for Condition 6. The coefficients for SSs ranged between 0.78 and 0.97 for Conditions 1 to 5 and 0.55 to 0.67 for Condition 6. The corresponding sound and prosthetic side COP variables demonstrated varying strengths of association with ES and SS. Clinical relevance Of the two clinical measures examined, the SSs are strongly reflective of COP excursion/velocity measures and these findings have application in the interpretation of SOT when evaluating balance in transtibial amputees.

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