scholarly journals Analysis of the Density Characteristics of Giant Cell Bone Tumors Treated with Denosumab According to CT Findings

Author(s):  
S. A. Tabakaev ◽  
I. G. Frolova ◽  
I. I. Anisenya ◽  
E. M. Slonimskaya ◽  
N. V. Vasilyev ◽  
...  

Background: Giant cell tumor of bone (GCTB) is a relatively common benign bone tumor, accounting for 4–9.5 % of all primary bone neoplasms. Localization of GCTB is one of the most important differential diagnostic criteria, since the tumor affects certain parts of the skeleton. Until now, surgical treatment was considered the method of choice in the treatment of GCTB. However, in recent years, denosumab, a genetically engineered drug, has been widely used to treat this tumor. Denosumab treatment of GCTB prevents further tumor progression and reduces tumor size. Histological examination of the surgical specimen is undoubtedly the most objective method for assessing the effectiveness of the treatment. However, it is sometimes necessary to get information regarding the effectiveness of conservative therapy.Purpose: To analyze the density characteristics of denosumab-treated GCTB using CT densitometry.Material and methods: The study included 15 patients aged 28–59 years with histologically verified giantcell tumor, who received denosumab treatment followed by surgery. Tumor structure was assessed before starting denosumab therapy, after 3 and 6 courses of denosumab therapy.Results: Changes in the density parameters (the mean tumor density, standard deviation of density, increase in the median tumor density and standard deviation of density, index of the relative density of the tumor) measured by CT images were analyzed. These changes were statistically significant in GCTB patients before initiating therapy with denosumab, and after 3 and 6 courses of denosumab therapy.Conclusion: Thus, CT densitometry is a useful tool for assessing the density characteristics of the tumor in GCS patients treated denosumab.

1969 ◽  
Vol 14 (9) ◽  
pp. 470-471
Author(s):  
M. DAVID MERRILL
Keyword(s):  

1972 ◽  
Vol 28 (03) ◽  
pp. 447-456 ◽  
Author(s):  
E. A Murphy ◽  
M. E Francis ◽  
J. F Mustard

SummaryThe characteristics of experimental error in measurement of platelet radioactivity have been explored by blind replicate determinations on specimens taken on several days on each of three Walker hounds.Analysis suggests that it is not unreasonable to suppose that error for each sample is normally distributed ; and while there is evidence that the variance is heterogeneous, no systematic relationship has been discovered between the mean and the standard deviation of the determinations on individual samples. Thus, since it would be impracticable for investigators to do replicate determinations as a routine, no improvement over simple unweighted least squares estimation on untransformed data suggests itself.


2020 ◽  
Vol 1 (2) ◽  
pp. 56-66
Author(s):  
Irma Linda

Background: Early marriages are at high risk of marital failure, poor family quality, young pregnancies at risk of maternal death, and the risk of being mentally ill to foster marriage and be responsible parents. Objective: To determine the effect of reproductive health education on peer groups (peers) on the knowledge and perceptions of adolescents about marriage age maturity. Method: This research uses the Quasi experimental method with One group pre and post test design, conducted from May to September 2018. The statistical analysis used in this study is a paired T test with a confidence level of 95% (α = 0, 05). Results: There is an average difference in the mean value of adolescent knowledge between the first and second measurements is 0.50 with a standard deviation of 1.922. The mean difference in mean scores of adolescent perceptions between the first and second measurements was 4.42 with a standard deviation of 9.611. Conclusion: There is a significant difference between adolescent knowledge on the pretest and posttest measurements with a value of P = 0.002, and there is a significant difference between adolescent perceptions on the pretest and posttest measurements with a value of p = 0.001. Increasing the number of facilities and facilities related to reproductive health education by peer groups (peers) in adolescents is carried out on an ongoing basis at school, in collaboration with local health workers as prevention of risky pregnancy.


1988 ◽  
Vol 60 (1) ◽  
pp. 1-29 ◽  
Author(s):  
E. D. Young ◽  
J. M. Robert ◽  
W. P. Shofner

1. The responses of neurons in the ventral cochlear nucleus (VCN) of decerebrate cats are described with regard to their regularity of discharge and latency. Regularity is measured by estimating the mean and standard deviation of interspike intervals as a function of time during responses to short tone bursts (25 ms). This method extends the usual interspike-interval analysis based on interval histograms by allowing the study of temporal changes in regularity during transient responses. The coefficient of variation (CV), equal to the ratio of standard deviation to mean interspike interval, is used as a measure of irregularity. Latency is measured as the mean and standard deviation of the latency of the first spike in response to short tone bursts, with 1.6-ms rise times. 2. The regularity and latency properties of the usual PST histogram response types are shown. Five major PST response type classes are used: chopper, primary-like, onset, onset-C, and unusual. The presence of a prepotential in a unit's action potentials is also noted; a prepotential implies that the unit is recorded from a bushy cell. 3. Units with chopper PST histograms give the most regular discharge. Three varieties of choppers are found. Chop-S units (regular choppers) have CVs less than 0.35 that are approximately constant during the response; chop-S units show no adaptation of instantaneous rate, as measured by the inverse of the mean interspike interval. Chop-T units have CVs greater than 0.35, show an increase in irregularity during the response and show substantial rate adaptation. Chop-U units have CVs greater than 0.35, show a decrease in irregularity during the response, and show a variety of rate adaptation behaviors, including negative adaptation (an increase in rate during a short-tone response). Irregular choppers (chop-T and chop-U units) rarely have CVs greater than 0.5. Choppers have the longest latencies of VCN units; all three groups have mean latencies at least 1 ms longer than the shortest auditory nerve (AN) fiber mean latencies. 4. Chopper units are recorded from stellate cells in VCN (35, 42). Our results for chopper units suggest a model for stellate cells in which a regularly firing action potential generator is driven by the summation of the AN inputs to the cell, where the summation is low-pass filtered by the membrane capacitance of the cell.(ABSTRACT TRUNCATED AT 400 WORDS)


2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 34.1-34
Author(s):  
R. S. Andev ◽  
N. Ahmad ◽  
A. Verdiyeva ◽  
R. Luqmani ◽  
S. Dubey

Background:Aortitis, a rare form of large vessel vasculitis, may occur in the context of a primary systemic vasculitis, as a part of systemic autoimmune disease or in isolation. The evidence and guidelines to diagnose, manage and monitor aortitis remain limited. However, PET CT and vascular MRI scans have facilitated our ability to make the diagnosis more readily. The optimal management strategy and complication rates remain uncertain.Objectives:Our aim was to explore the clinical, laboratory and radiological features of aortitis. We sought to review the management and complications of this illness by collecting detailed information on the outcomes and treatments used, including disease modifying agents (DMARDs) and biologics.Methods:Patients diagnosed with aortitis since 2006 that had been managed in a single tertiary centre were identified using the Rheumatology Assessment Database Innovation in Oxford (RHADIO). Their medical notes were retrospectively reviewed using a local electronic patient record system and the following information was obtained: demographics, underlying risk factors, imaging and laboratory results (including biopsy reports if available), management and outcome.Results:We identified 155 patients who met the inclusion criteria. There was a female preponderance of 57.4% (n=89). At the time of diagnosis, the average age was 69 (range 30-92) and the mean symptomatology length prior to diagnosis was 12 months (range 0-120). The majority of patients (60.4%, n=94) had aortitis secondary to giant cell arteritis (GCA), isolated aortitis was identified in 29.7% (n=46) and IgG4-related disease aortitis was uncommon (2.6%, n=4). Those with cranial GCA-like symptoms were diagnosed on average 3.9 months before those who presented differently (10.1 months versus 14.0 months).Common presentations comprised: systemic inflammatory response syndrome (49.0%, n=76), cranial GCA-like symptoms (26.5%, n=41) and unexplained weight loss (24.5%, n=38). Importantly, 18.7% (n=29) of patients presented with ischaemic symptoms that included angina, TIAs/strokes and claudication. Aortic dissection was the primary presentation for 6.5% (n=10) of patients.At presentation, the mean CRP was 84 mg/L (range 1-249) and the ESR was 72 mm/hr (range 2-164). Most (73.5%, n=114) had diagnostic PET CT changes. For those patients with GCA, diagnostic ultrasound changes were seen in 27.7% (n=26).Nearly all were treated with prednisolone (92.3%, n=143) and all but 8 (5.1%) received a DMARD at some point. Methotrexate was the most commonly used DMARD (93.9%, n=138), followed by leflunomide (22.3%, n=35) and azathioprine (19.1%, n=28). Cyclophosphamide was used in 23.8% of patients (n=38) and 15 patients (9.7%) received tocilizumab.Around a third (34.1% n=53/155) had received at least two DMARDs during their treatment course. On average, patients required 3.46 drugs to manage their aortitis. Those who relapsed (43.2%, n=67) were more likely to have GCA (65.7%, n=44).Vascular sequelae were present in 37.4% (n=58). The most common complications were ischaemic in nature with stroke/TIA and claudication reported in 16.8% (n=26). Aortic aneurysms were recorded in 11.6% (n=18) of cases and 5.1% (n=8) developed dissections despite being on treatment for their aortitis. One patient developed renal infarcts and ischaemic bowel leading to intestinal failure because of florid vasculitis.Conclusion:Aortitis has a varied presentation with systemic inflammatory response syndrome being the most common. Delayed diagnosis remains a problem and especially for those with non-GCA related aortitis, which is likely to contribute to the risk of subsequent vascular complications. Vascular events including dissection are common, many of which could be preventable, emphasising the importance of early diagnosis and good disease control.References:[1]Koster M et al. Large-vessel giant cell arteritis: diagnosis, monitoring and management. Rheumatology [Internet]. 2018 Feb 1;57(suppl_2):ii32–42. Available from: https://doi.org/10.1093/rheumatology/kex424Disclosure of Interests:None declared


Cancers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 2421
Author(s):  
Roberta Fusco ◽  
Vincenza Granata ◽  
Mauro Mattace Raso ◽  
Paolo Vallone ◽  
Alessandro Pasquale De Rosa ◽  
...  

Purpose. To combine blood oxygenation level dependent magnetic resonance imaging (BOLD-MRI), dynamic contrast enhanced MRI (DCE-MRI), and diffusion weighted MRI (DW-MRI) in differentiation of benign and malignant breast lesions. Methods. Thirty-seven breast lesions (11 benign and 21 malignant lesions) pathologically proven were included in this retrospective preliminary study. Pharmaco-kinetic parameters including Ktrans, kep, ve, and vp were extracted by DCE-MRI; BOLD parameters were estimated by basal signal S0 and the relaxation rate R2*; and diffusion and perfusion parameters were derived by DW-MRI (pseudo-diffusion coefficient (Dp), perfusion fraction (fp), and tissue diffusivity (Dt)). The correlation coefficient, Wilcoxon-Mann-Whitney U-test, and receiver operating characteristic (ROC) analysis were calculated and area under the ROC curve (AUC) was obtained. Moreover, pattern recognition approaches (linear discrimination analysis and decision tree) with balancing technique and leave one out cross validation approach were considered. Results. R2* and D had a significant negative correlation (−0.57). The mean value, standard deviation, Skewness and Kurtosis values of R2* did not show a statistical significance between benign and malignant lesions (p > 0.05) confirmed by the ‘poor’ diagnostic value of ROC analysis. For DW-MRI derived parameters, the univariate analysis, standard deviation of D, Skewness and Kurtosis values of D* had a significant result to discriminate benign and malignant lesions and the best result at the univariate analysis in the discrimination of benign and malignant lesions was obtained by the Skewness of D* with an AUC of 82.9% (p-value = 0.02). Significant results for the mean value of Ktrans, mean value, standard deviation value and Skewness of kep, mean value, Skewness and Kurtosis of ve were obtained and the best AUC among DCE-MRI extracted parameters was reached by the mean value of kep and was equal to 80.0%. The best diagnostic performance in the discrimination of benign and malignant lesions was obtained at the multivariate analysis considering the DCE-MRI parameters alone with an AUC = 0.91 when the balancing technique was considered. Conclusions. Our results suggest that the combined use of DCE-MRI, DW-MRI and/or BOLD-MRI does not provide a dramatic improvement compared to the use of DCE-MRI features alone, in the classification of breast lesions. However, an interesting result was the negative correlation between R2* and D.


2021 ◽  
Vol 9 (6) ◽  
pp. 585
Author(s):  
Minghao Wu ◽  
Leen De Vos ◽  
Carlos Emilio Arboleda Chavez ◽  
Vasiliki Stratigaki ◽  
Maximilian Streicher ◽  
...  

The present work introduces an analysis of the measurement and model effects that exist in monopile scour protection experiments with repeated small scale tests. The damage erosion is calculated using the three dimensional global damage number S3D and subarea damage number S3D,i. Results show that the standard deviation of the global damage number σ(S3D)=0.257 and is approximately 20% of the mean S3D, and the standard deviation of the subarea damage number σ(S3D,i)=0.42 which can be up to 33% of the mean S3D. The irreproducible maximum wave height, chaotic flow field and non-repeatable armour layer construction are regarded as the main reasons for the occurrence of strong model effects. The measurement effects are limited to σ(S3D)=0.039 and σ(S3D,i)=0.083, which are minor compared to the model effects.


2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 93.2-94
Author(s):  
L. C. Burg ◽  
P. Brossart ◽  
K. I. Reinking ◽  
R. P. Finger ◽  
C. Behning ◽  
...  

Background:Giant cell arteritis (GCA) is the most common form of systemic vasculitis in patients aged 50 years and older.1Visual symptoms such as amaurosis, diplopia, temporary or permanent visual field loss secondary to optic nerve ischemia are common manifestations.2The value of vascular ultrasound of extra-ocular vessels in diagnosing GCA is well established.3However, the role of transocular ultrasound of the central retinal artery in GCA patients has not yet been established.Objectives:To identify changes in flow velocities of the central retinal artery in GCA patients with visual symptoms and controls with transocular high resolution ultrasound.Methods:Prospective analysis of GCA patients with visual symptoms and controls. Ultrasound of the central retinal artery was performed in 18 newly diagnosed consecutive GCA patients with visual symptoms (GCA-group) and 25 controls without ocular pathology. Visual symptoms included amaurosis, diplopia and temporary or permanent visual field loss. For each eye, peak systolic values (PS) and end diastolic values (ED) were recorded. Furthermore, the resistance index of each central retinal artery was measured.Results:Twenty-one of 36 eyes of 18 GCA patients were affected. Therefore 21 central retinal were measured. The control group consisted of 50 central retinal arteries of 25 eye-healthy individuals. The mean age and gender distribution of the GCA-group were 75.6 years (SD± 8.1) with eight females (44 %) and 67 years (SD± 8.9) with twelve females (48%) in the control group. The mean flow velocity of the central retinal artery was PS 12.2 cm/s (SD± 3.5) and ED 3.7 cm/s (SD± 1.2) in the GCA group and PS 14.4 cm/s (SD± 3.2) and ED 5.1 cm/s (SD± 1.6) in the control group. The mean RI was 0.9 (SD± 0.3) in the GCA group and 0.8 (SD± 0.3) in the control group. Mean reduction in flow velocity in the GCA-group was PS 2.1 cm/s (p= 0.039) and ED 1.4 (p= 0.0004) cm/s, while the RI was increased by 0.14 (p= 0.077). The results for PS and ED measurements were statistically significant, while the results for RI were not significant.Conclusion:In GCA patients with ocular symptoms, a reduction of flow velocities of the central retinal artery compared to the eye-healthy control group was found. Results for PS and ED were significant. There seems to be a trend for decreased flow velocities in coexistence with visual symptoms in patients with GCA.References:[1]Warrington KJ, Matteson EL. Management guidelines and outcome measures in giant cell arteritis (GCA). Clin Exp Rheumatol 2007;25:137–41.[2]Chean CS, Prior JA, Helliwell T, et al. Characteristics of patients with giant cell arteritis who experience visual symptoms. Rheumatol Int 2019;39:1789–96.[3]Dejaco C, Ramiro S, Duftner C, et al. EULAR recommendations for the use of imaging in large vessel vasculitis in clinical practice. Ann Rheum Dis 2018;77:636–43Figure 1.Transocular ultrasound of an affected eye in giant cell arteritis with reduced flow velocities and increased resistance index.Disclosure of Interests:None declared


Author(s):  
Athanasios N. Papadimopoulos ◽  
Stamatios A. Amanatiadis ◽  
Nikolaos V. Kantartzis ◽  
Theodoros T. Zygiridis ◽  
Theodoros D. Tsiboukis

Purpose Important statistical variations are likely to appear in the propagation of surface plasmon polariton waves atop the surface of graphene sheets, degrading the expected performance of real-life THz applications. This paper aims to introduce an efficient numerical algorithm that is able to accurately and rapidly predict the influence of material-based uncertainties for diverse graphene configurations. Design/methodology/approach Initially, the surface conductivity of graphene is described at the far infrared spectrum and the uncertainties of its main parameters, namely, the chemical potential and the relaxation time, on the propagation properties of the surface waves are investigated, unveiling a considerable impact. Furthermore, the demanding two-dimensional material is numerically modeled as a surface boundary through a frequency-dependent finite-difference time-domain scheme, while a robust stochastic realization is accordingly developed. Findings The mean value and standard deviation of the propagating surface waves are extracted through a single-pass simulation in contrast to the laborious Monte Carlo technique, proving the accomplished high efficiency. Moreover, numerical results, including graphene’s surface current density and electric field distribution, indicate the notable precision, stability and convergence of the new graphene-based stochastic time-domain method in terms of the mean value and the order of magnitude of the standard deviation. Originality/value The combined uncertainties of the main parameters in graphene layers are modeled through a high-performance stochastic numerical algorithm, based on the finite-difference time-domain method. The significant accuracy of the numerical results, compared to the cumbersome Monte Carlo analysis, renders the featured technique a flexible computational tool that is able to enhance the design of graphene THz devices due to the uncertainty prediction.


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