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Sample records for tissue complication probability

  1. Normal tissue complication probability for salivary glands

    International Nuclear Information System (INIS)

    Rana, B.S.

    2008-01-01

    The purpose of radiotherapy is to make a profitable balance between the morbidity (due to side effects of radiation) and cure of malignancy. To achieve this, one needs to know the relation between NTCP (normal tissue complication probability) and various treatment variables of a schedule viz. daily dose, duration of treatment, total dose and fractionation along with tissue conditions. Prospective studies require that a large number of patients be treated with varied schedule parameters and a statistically acceptable number of patients develop complications so that a true relation between NTCP and a particular variable is established. In this study Salivary Glands Complications have been considered. The cases treated in 60 Co teletherapy machine during the period 1994 to 2002 were analyzed and the clinicians judgement in ascertaining the end points was the only means of observations. The only end points were early and late xerestomia which were considered for NTCP evaluations for a period of 5 years

  2. Statistical validation of normal tissue complication probability models

    NARCIS (Netherlands)

    Xu, Cheng-Jian; van der Schaaf, Arjen; van t Veld, Aart; Langendijk, Johannes A.; Schilstra, Cornelis

    2012-01-01

    PURPOSE: To investigate the applicability and value of double cross-validation and permutation tests as established statistical approaches in the validation of normal tissue complication probability (NTCP) models. METHODS AND MATERIALS: A penalized regression method, LASSO (least absolute shrinkage

  3. Statistical Validation of Normal Tissue Complication Probability Models

    Energy Technology Data Exchange (ETDEWEB)

    Xu Chengjian, E-mail: c.j.xu@umcg.nl [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Schaaf, Arjen van der; Veld, Aart A. van' t; Langendijk, Johannes A. [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Schilstra, Cornelis [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Radiotherapy Institute Friesland, Leeuwarden (Netherlands)

    2012-09-01

    Purpose: To investigate the applicability and value of double cross-validation and permutation tests as established statistical approaches in the validation of normal tissue complication probability (NTCP) models. Methods and Materials: A penalized regression method, LASSO (least absolute shrinkage and selection operator), was used to build NTCP models for xerostomia after radiation therapy treatment of head-and-neck cancer. Model assessment was based on the likelihood function and the area under the receiver operating characteristic curve. Results: Repeated double cross-validation showed the uncertainty and instability of the NTCP models and indicated that the statistical significance of model performance can be obtained by permutation testing. Conclusion: Repeated double cross-validation and permutation tests are recommended to validate NTCP models before clinical use.

  4. Statistical validation of normal tissue complication probability models.

    Science.gov (United States)

    Xu, Cheng-Jian; van der Schaaf, Arjen; Van't Veld, Aart A; Langendijk, Johannes A; Schilstra, Cornelis

    2012-09-01

    To investigate the applicability and value of double cross-validation and permutation tests as established statistical approaches in the validation of normal tissue complication probability (NTCP) models. A penalized regression method, LASSO (least absolute shrinkage and selection operator), was used to build NTCP models for xerostomia after radiation therapy treatment of head-and-neck cancer. Model assessment was based on the likelihood function and the area under the receiver operating characteristic curve. Repeated double cross-validation showed the uncertainty and instability of the NTCP models and indicated that the statistical significance of model performance can be obtained by permutation testing. Repeated double cross-validation and permutation tests are recommended to validate NTCP models before clinical use. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. Options and pitfalls of normal tissues complication probability models

    International Nuclear Information System (INIS)

    Dorr, Wolfgang

    2011-01-01

    Full text: Technological improvements in the physical administration of radiotherapy have led to increasing conformation of the treatment volume (TV) with the planning target volume (PTV) and of the irradiated volume (IV) with the TV. In this process of improvement of the physical quality of radiotherapy, the total volumes of organs at risk exposed to significant doses have significantly decreased, resulting in increased inhomogeneities in the dose distributions within these organs. This has resulted in a need to identify and quantify volume effects in different normal tissues. Today, irradiated volume today must be considered a 6t h 'R' of radiotherapy, in addition to the 5 'Rs' defined by Withers and Steel in the mid/end 1980 s. The current status of knowledge of these volume effects has recently been summarized for many organs and tissues by the QUANTEC (Quantitative Analysis of Normal Tissue Effects in the Clinic) initiative [Int. J. Radiat. Oncol. BioI. Phys. 76 (3) Suppl., 2010]. However, the concept of using dose-volume histogram parameters as a basis for dose constraints, even without applying any models for normal tissue complication probabilities (NTCP), is based on (some) assumptions that are not met in clinical routine treatment planning. First, and most important, dose-volume histogram (DVH) parameters are usually derived from a single, 'snap-shot' CT-scan, without considering physiological (urinary bladder, intestine) or radiation induced (edema, patient weight loss) changes during radiotherapy. Also, individual variations, or different institutional strategies of delineating organs at risk are rarely considered. Moreover, the reduction of the 3-dimentional dose distribution into a '2dimensl' DVH parameter implies that the localization of the dose within an organ is irrelevant-there are ample examples that this assumption is not justified. Routinely used dose constraints also do not take into account that the residual function of an organ may be

  6. Normal tissue complication probability (NTCP), the clinician,s perspective

    International Nuclear Information System (INIS)

    Yeoh, E.K.

    2011-01-01

    Full text: 3D radiation treatment planning has enabled dose distributions to be related to the volume of normal tissues irradiated. The dose volume histograms thus derived have been utilized to set NTCP dose constraints to facilitate optimization of treatment planning. However, it is not widely appreciated that a number of important variables other than DYH's which determine NTCP in the individual patient. These variables will be discussed under the headings of patient and treatment related as well as tumour related factors. Patient related factors include age, co-morbidities such as connective tissue disease and diabetes mellitus, previous tissue/organ damage, tissue architectural organization (parallel or serial), regional tissue/organ and individual tissue/organ radiosensitivities as well as the development of severe acute toxicity. Treatment related variables which need to be considered include dose per fraction (if not the conventional 1.8012.00 Gy/fraction, particularly for IMRT), number of fractions and total dose, dose rate (particularly if combined with brachytherapy) and concurrent chemotherapy or other biological dose modifiers. Tumour related factors which impact on NTCP include infiltration of normal tissue/organ usually at presentation leading to compromised function but also with recurrent disease after radiation therapy as well as variable tumour radiosensitivities between and within tumour types. Whilst evaluation of DYH data is a useful guide in the choice of treatment plan, the current state of knowledge requires the clinician to make an educated judgement based on a consideration of the other factors.

  7. Impact of statistical learning methods on the predictive power of multivariate normal tissue complication probability models

    NARCIS (Netherlands)

    Xu, Cheng-Jian; van der Schaaf, Arjen; Schilstra, Cornelis; Langendijk, Johannes A.; van t Veld, Aart A.

    2012-01-01

    PURPOSE: To study the impact of different statistical learning methods on the prediction performance of multivariate normal tissue complication probability (NTCP) models. METHODS AND MATERIALS: In this study, three learning methods, stepwise selection, least absolute shrinkage and selection operator

  8. Calculation of normal tissue complication probability and dose-volume histogram reduction schemes for tissues with a critical element architecture

    International Nuclear Information System (INIS)

    Niemierko, Andrzej; Goitein, Michael

    1991-01-01

    The authors investigate a model of normal tissue complication probability for tissues that may be represented by a critical element architecture. They derive formulas for complication probability that apply to both a partial volume irradiation and to an arbitrary inhomogeneous dose distribution. The dose-volume isoeffect relationship which is a consequence of a critical element architecture is discussed and compared to the empirical power law relationship. A dose-volume histogram reduction scheme for a 'pure' critical element model is derived. In addition, a point-based algorithm which does not require precomputation of a dose-volume histogram is derived. The existing published dose-volume histogram reduction algorithms are analyzed. The authors show that the existing algorithms, developed empirically without an explicit biophysical model, have a close relationship to the critical element model at low levels of complication probability. However, it is also showed that they have aspects which are not compatible with a critical element model and the authors propose a modification to one of them to circumvent its restriction to low complication probabilities. (author). 26 refs.; 7 figs

  9. Improving normal tissue complication probability models: the need to adopt a "data-pooling" culture.

    Science.gov (United States)

    Deasy, Joseph O; Bentzen, Søren M; Jackson, Andrew; Ten Haken, Randall K; Yorke, Ellen D; Constine, Louis S; Sharma, Ashish; Marks, Lawrence B

    2010-03-01

    Clinical studies of the dependence of normal tissue response on dose-volume factors are often confusingly inconsistent, as the QUANTEC reviews demonstrate. A key opportunity to accelerate progress is to begin storing high-quality datasets in repositories. Using available technology, multiple repositories could be conveniently queried, without divulging protected health information, to identify relevant sources of data for further analysis. After obtaining institutional approvals, data could then be pooled, greatly enhancing the capability to construct predictive models that are more widely applicable and better powered to accurately identify key predictive factors (whether dosimetric, image-based, clinical, socioeconomic, or biological). Data pooling has already been carried out effectively in a few normal tissue complication probability studies and should become a common strategy. Copyright 2010 Elsevier Inc. All rights reserved.

  10. Hypothyroidism after primary radiotherapy for head and neck squamous cell carcinoma: Normal tissue complication probability modeling with latent time correction

    DEFF Research Database (Denmark)

    Rønjom, Marianne Feen; Brink, Carsten; Bentzen, Søren

    2013-01-01

    To develop a normal tissue complication probability (NTCP) model of radiation-induced biochemical hypothyroidism (HT) after primary radiotherapy for head and neck squamous cell carcinoma (HNSCC) with adjustment for latency and clinical risk factors.......To develop a normal tissue complication probability (NTCP) model of radiation-induced biochemical hypothyroidism (HT) after primary radiotherapy for head and neck squamous cell carcinoma (HNSCC) with adjustment for latency and clinical risk factors....

  11. Impact of Statistical Learning Methods on the Predictive Power of Multivariate Normal Tissue Complication Probability Models

    Energy Technology Data Exchange (ETDEWEB)

    Xu Chengjian, E-mail: c.j.xu@umcg.nl [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Schaaf, Arjen van der; Schilstra, Cornelis; Langendijk, Johannes A.; Veld, Aart A. van' t [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands)

    2012-03-15

    Purpose: To study the impact of different statistical learning methods on the prediction performance of multivariate normal tissue complication probability (NTCP) models. Methods and Materials: In this study, three learning methods, stepwise selection, least absolute shrinkage and selection operator (LASSO), and Bayesian model averaging (BMA), were used to build NTCP models of xerostomia following radiotherapy treatment for head and neck cancer. Performance of each learning method was evaluated by a repeated cross-validation scheme in order to obtain a fair comparison among methods. Results: It was found that the LASSO and BMA methods produced models with significantly better predictive power than that of the stepwise selection method. Furthermore, the LASSO method yields an easily interpretable model as the stepwise method does, in contrast to the less intuitive BMA method. Conclusions: The commonly used stepwise selection method, which is simple to execute, may be insufficient for NTCP modeling. The LASSO method is recommended.

  12. Impact of statistical learning methods on the predictive power of multivariate normal tissue complication probability models.

    Science.gov (United States)

    Xu, Cheng-Jian; van der Schaaf, Arjen; Schilstra, Cornelis; Langendijk, Johannes A; van't Veld, Aart A

    2012-03-15

    To study the impact of different statistical learning methods on the prediction performance of multivariate normal tissue complication probability (NTCP) models. In this study, three learning methods, stepwise selection, least absolute shrinkage and selection operator (LASSO), and Bayesian model averaging (BMA), were used to build NTCP models of xerostomia following radiotherapy treatment for head and neck cancer. Performance of each learning method was evaluated by a repeated cross-validation scheme in order to obtain a fair comparison among methods. It was found that the LASSO and BMA methods produced models with significantly better predictive power than that of the stepwise selection method. Furthermore, the LASSO method yields an easily interpretable model as the stepwise method does, in contrast to the less intuitive BMA method. The commonly used stepwise selection method, which is simple to execute, may be insufficient for NTCP modeling. The LASSO method is recommended. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. Impact of Statistical Learning Methods on the Predictive Power of Multivariate Normal Tissue Complication Probability Models

    International Nuclear Information System (INIS)

    Xu Chengjian; Schaaf, Arjen van der; Schilstra, Cornelis; Langendijk, Johannes A.; Veld, Aart A. van’t

    2012-01-01

    Purpose: To study the impact of different statistical learning methods on the prediction performance of multivariate normal tissue complication probability (NTCP) models. Methods and Materials: In this study, three learning methods, stepwise selection, least absolute shrinkage and selection operator (LASSO), and Bayesian model averaging (BMA), were used to build NTCP models of xerostomia following radiotherapy treatment for head and neck cancer. Performance of each learning method was evaluated by a repeated cross-validation scheme in order to obtain a fair comparison among methods. Results: It was found that the LASSO and BMA methods produced models with significantly better predictive power than that of the stepwise selection method. Furthermore, the LASSO method yields an easily interpretable model as the stepwise method does, in contrast to the less intuitive BMA method. Conclusions: The commonly used stepwise selection method, which is simple to execute, may be insufficient for NTCP modeling. The LASSO method is recommended.

  14. Normal Tissue Complication Probability Modeling of Acute Hematologic Toxicity in Cervical Cancer Patients Treated With Chemoradiotherapy

    International Nuclear Information System (INIS)

    Rose, Brent S.; Aydogan, Bulent; Liang, Yun; Yeginer, Mete; Hasselle, Michael D.; Dandekar, Virag; Bafana, Rounak; Yashar, Catheryn M.; Mundt, Arno J.; Roeske, John C.; Mell, Loren K.

    2011-01-01

    Purpose: To test the hypothesis that increased pelvic bone marrow (BM) irradiation is associated with increased hematologic toxicity (HT) in cervical cancer patients undergoing chemoradiotherapy and to develop a normal tissue complication probability (NTCP) model for HT. Methods and Materials: We tested associations between hematologic nadirs during chemoradiotherapy and the volume of BM receiving ≥10 and 20 Gy (V 10 and V 20 ) using a previously developed linear regression model. The validation cohort consisted of 44 cervical cancer patients treated with concurrent cisplatin and pelvic radiotherapy. Subsequently, these data were pooled with data from 37 identically treated patients from a previous study, forming a cohort of 81 patients for normal tissue complication probability analysis. Generalized linear modeling was used to test associations between hematologic nadirs and dosimetric parameters, adjusting for body mass index. Receiver operating characteristic curves were used to derive optimal dosimetric planning constraints. Results: In the validation cohort, significant negative correlations were observed between white blood cell count nadir and V 10 (regression coefficient (β) = -0.060, p = 0.009) and V 20 (β = -0.044, p = 0.010). In the combined cohort, the (adjusted) β estimates for log (white blood cell) vs. V 10 and V 20 were as follows: -0.022 (p = 0.025) and -0.021 (p = 0.002), respectively. Patients with V 10 ≥ 95% were more likely to experience Grade ≥3 leukopenia (68.8% vs. 24.6%, p 20 > 76% (57.7% vs. 21.8%, p = 0.001). Conclusions: These findings support the hypothesis that HT increases with increasing pelvic BM volume irradiated. Efforts to maintain V 10 20 < 76% may reduce HT.

  15. The use of normal tissue complication probability to predict radiation hepatitis

    International Nuclear Information System (INIS)

    Keum, Ki Chang; Seong, Jin Sil; Suh, Chang Ok; Lee, Sang Wook; Chung, Eun Ji; Shin, Hyun Soo; Kim, Gwi Eon

    2000-01-01

    Although it has been known that the tolerance of the liver to external beam irradiation depends on the irradiated volume and dose, few data exist which quantify this dependence. However, recently, with the development of three dimensional (3-D) treatment planning, have the tools to quantify the relationships between dose, volume, and normal tissue complications become available. The objective of this study is to investigate the relationships between normal tissue complication probability (NTCP) and the risk of radiation hepatitis for patients who received variant dose partial liver irradiation. From March 1992 to December 1994, 10 patients with hepatoma and 10 patients with bile duct cancer were included in this study. Eighteen patients had normal hepatic function, but 2 patients (prothrombin time 73%, 68%) had mild liver cirrhosis before irradiation. Radiation therapy was delivered with 10MV linear accelerator, 180-200 cGy fraction per day. The total dose ranged from 3,960 cGy to 6,000 cGy (median dose 5,040 cGy). The normal tissue complication probability was calculated by using Lyman's model. Radiation hepatitis was defined as the development of anicteric elevation of alkaline phosphatase of at least two fold and non-malignant ascites in the absence of documented progressive. The calculated NTCP ranged from 0.001 to 0.840 (median 0.05). Three of the 20 patients developed radiation hepatitis. The NTCP of the patients with radiation hepatitis were 0.390, 0.528, 0.844 (median: O.58±0.23), but that of the patients without radiation hepatitis ranged from 0.001 to 0.308 (median: 0.09±0.09). When the NTCP was calculated by using the volume factor of 0.32, a radiation hepatitis was observed only in patients with the NTCP value more than 0.39. By contrast, clinical results of evolving radiation hepatitis were not well correlated with NTCP value calculated when the volume factor of 0.69 was applied. On the basis of these observations, volume factor of 0.32 was more

  16. A simple method to calculate the influence of dose inhomogeneity and fractionation in normal tissue complication probability evaluation

    International Nuclear Information System (INIS)

    Begnozzi, L.; Gentile, F.P.; Di Nallo, A.M.; Chiatti, L.; Zicari, C.; Consorti, R.; Benassi, M.

    1994-01-01

    Since volumetric dose distributions are available with 3-dimensional radiotherapy treatment planning they can be used in statistical evaluation of response to radiation. This report presents a method to calculate the influence of dose inhomogeneity and fractionation in normal tissue complication probability evaluation. The mathematical expression for the calculation of normal tissue complication probability has been derived combining the Lyman model with the histogram reduction method of Kutcher et al. and using the normalized total dose (NTD) instead of the total dose. The fitting of published tolerance data, in case of homogeneous or partial brain irradiation, has been considered. For the same total or partial volume homogeneous irradiation of the brain, curves of normal tissue complication probability have been calculated with fraction size of 1.5 Gy and of 3 Gy instead of 2 Gy, to show the influence of fraction size. The influence of dose distribution inhomogeneity and α/β value has also been simulated: Considering α/β=1.6 Gy or α/β=4.1 Gy for kidney clinical nephritis, the calculated curves of normal tissue complication probability are shown. Combining NTD calculations and histogram reduction techniques, normal tissue complication probability can be estimated taking into account the most relevant contributing factors, including the volume effect. (orig.) [de

  17. Investigation of normal tissue complication probabilities in prostate and partial breast irradiation radiotherapy techniques

    International Nuclear Information System (INIS)

    Bezak, E.; Takam, R.; Bensaleh, S.; Yeoh, E.; Marcu, L.

    2011-01-01

    Full text: Normal- Tissue-Complication Probabilities of rectum, bladder and urethra following various radiation techniques for prostate cancer were evaluated using the relative-seriality and Lyman models. NTCPs of lungs, heart and skin, their dependence on sourceposition, balloon-deformation were also investigated for HDR mammosite brachytherapy. The prostate treatment techniques included external three dimentional conformal-radiotherapy, Low-Dose-Rate brachytherapy (1-125), High-Dose-Rate brachytherapy (Ir-I92). Dose- Volume-Histograms of critical structures for prostate and breast radiotherapy, retrieved from corresponding treatment planning systems, were converted to Biological Effective Dose (BEffD)-based and Equivalent Dose(Deq)-based DVHs to account for differences in radiation delivery and fractionation schedule. Literature-based model parameters were used to calculate NTCPs. Hypofractionated 3D-CRT (2.75 Gy/fraction, total dose 55 Gy) NTCPs of rectum, bladder and urethra were less than those for standard fractionated 4-field 3D-CRT (2-Gy/fraction, 64 Gy) and dose-escalated 4- and 5-field 3D-CRT (74 Gy). Rectal and bladder NTCPs (5.2% and 6.6%) following the dose-escalated 4-field 3D-CRT (74 Gy) were the highest among analyzed techniques. The average NTCP for rectum and urethra were 0.6% and 24.7% for LDRBT and 0.5% and 11.2% for HDR-BT. For Mammosite, NTCP was estimated to be 0.1 %, 0.1 %, 1.2% and 3.5% for skin desquamation, erythema, telangiectasia and fibrosis respectively (the source positioned at the balloon centre). A 4 mm Mammosite-balloon deformation leads to overdosing of PTV regions by ∼40%, resulting in excessive skin dose and increased NTCP. Conclusions Prostate brachytherapy resulted in NTCPs lower compared to external beam techniques. Mammosite-brachytherapy resulted in no heart/lung complications regardless of balloon deformation. However, 4 mm deformation caused 0.6% increase in tissue fibrosis NTCP.

  18. Normal tissue complication probabilities correlated with late effects in the rectum after prostate conformal radiotherapy

    International Nuclear Information System (INIS)

    Dale, Einar; Olsen, Dag R.; Fossa, Sophie D.

    1999-01-01

    Purpose: Radiation therapy of deep-sited tumours will always result in normal tissue doses to some extent. The aim of this study was to calculate different risk estimates of late effects in the rectum for a group of cancer prostate patients treated with conformal radiation therapy (CRT) and correlate these estimates with the occurrences of late effects. Since the rectum is a hollow organ, several ways of generating dose-volume distributions over the organ are possible, and we wanted to investigate two of them. Methods and Materials: A mathematical model, known as the Lyman-Kutcher model, conventionally used to estimate normal tissue complication probabilities (NTCP) associated with radiation therapy, was applied to a material of 52 cancer prostate patients. The patients were treated with a four field box technique, with the rectum as organ at risk. Dose-volume histograms (DVH) were generated for the whole rectum (including the cavity) and of the rectum wall. One to two years after the treatment, the patients completed a questionnaire concerning bowel (rectum) related morbidity quantifying the extent of late effects. Results: A correlation analysis using Spearman's rank correlation coefficient, for NTCP values calculated from the DVHs and the patients' scores, gave correlation coefficients which were not statistically significant at the p max , of the whole rectum, correlated better to observed late toxicity than D max derived from histograms of the rectum wall. Correlation coefficients from 'high-dose' measures were larger than those calculated from the NTCP values. Accordingly, as the volume parameter of the Lyman-Kutcher model was reduced, raising the impact of small high-dose volumes on the NTCP values, the correlation between observed effects and NTCP values became significant at p < 0.01 level. Conclusions: 1) High-dose levels corresponding to small volume fractions of the cumulative dose-volume histograms were best correlated with the occurrences of late

  19. Method for Automatic Selection of Parameters in Normal Tissue Complication Probability Modeling.

    Science.gov (United States)

    Christophides, Damianos; Appelt, Ane L; Gusnanto, Arief; Lilley, John; Sebag-Montefiore, David

    2018-07-01

    To present a fully automatic method to generate multiparameter normal tissue complication probability (NTCP) models and compare its results with those of a published model, using the same patient cohort. Data were analyzed from 345 rectal cancer patients treated with external radiation therapy to predict the risk of patients developing grade 1 or ≥2 cystitis. In total, 23 clinical factors were included in the analysis as candidate predictors of cystitis. Principal component analysis was used to decompose the bladder dose-volume histogram into 8 principal components, explaining more than 95% of the variance. The data set of clinical factors and principal components was divided into training (70%) and test (30%) data sets, with the training data set used by the algorithm to compute an NTCP model. The first step of the algorithm was to obtain a bootstrap sample, followed by multicollinearity reduction using the variance inflation factor and genetic algorithm optimization to determine an ordinal logistic regression model that minimizes the Bayesian information criterion. The process was repeated 100 times, and the model with the minimum Bayesian information criterion was recorded on each iteration. The most frequent model was selected as the final "automatically generated model" (AGM). The published model and AGM were fitted on the training data sets, and the risk of cystitis was calculated. The 2 models had no significant differences in predictive performance, both for the training and test data sets (P value > .05) and found similar clinical and dosimetric factors as predictors. Both models exhibited good explanatory performance on the training data set (P values > .44), which was reduced on the test data sets (P values < .05). The predictive value of the AGM is equivalent to that of the expert-derived published model. It demonstrates potential in saving time, tackling problems with a large number of parameters, and standardizing variable selection in NTCP

  20. Multivariate Normal Tissue Complication Probability Modeling of Heart Valve Dysfunction in Hodgkin Lymphoma Survivors

    International Nuclear Information System (INIS)

    Cella, Laura; Liuzzi, Raffaele; Conson, Manuel; D’Avino, Vittoria; Salvatore, Marco; Pacelli, Roberto

    2013-01-01

    Purpose: To establish a multivariate normal tissue complication probability (NTCP) model for radiation-induced asymptomatic heart valvular defects (RVD). Methods and Materials: Fifty-six patients treated with sequential chemoradiation therapy for Hodgkin lymphoma (HL) were retrospectively reviewed for RVD events. Clinical information along with whole heart, cardiac chambers, and lung dose distribution parameters was collected, and the correlations to RVD were analyzed by means of Spearman's rank correlation coefficient (Rs). For the selection of the model order and parameters for NTCP modeling, a multivariate logistic regression method using resampling techniques (bootstrapping) was applied. Model performance was evaluated using the area under the receiver operating characteristic curve (AUC). Results: When we analyzed the whole heart, a 3-variable NTCP model including the maximum dose, whole heart volume, and lung volume was shown to be the optimal predictive model for RVD (Rs = 0.573, P<.001, AUC = 0.83). When we analyzed the cardiac chambers individually, for the left atrium and for the left ventricle, an NTCP model based on 3 variables including the percentage volume exceeding 30 Gy (V30), cardiac chamber volume, and lung volume was selected as the most predictive model (Rs = 0.539, P<.001, AUC = 0.83; and Rs = 0.557, P<.001, AUC = 0.82, respectively). The NTCP values increase as heart maximum dose or cardiac chambers V30 increase. They also increase with larger volumes of the heart or cardiac chambers and decrease when lung volume is larger. Conclusions: We propose logistic NTCP models for RVD considering not only heart irradiation dose but also the combined effects of lung and heart volumes. Our study establishes the statistical evidence of the indirect effect of lung size on radio-induced heart toxicity

  1. A new plan-scoring method using normal tissue complication probability for personalized treatment plan decisions in prostate cancer

    Science.gov (United States)

    Kim, Kwang Hyeon; Lee, Suk; Shim, Jang Bo; Yang, Dae Sik; Yoon, Won Sup; Park, Young Je; Kim, Chul Yong; Cao, Yuan Jie; Chang, Kyung Hwan

    2018-01-01

    The aim of this study was to derive a new plan-scoring index using normal tissue complication probabilities to verify different plans in the selection of personalized treatment. Plans for 12 patients treated with tomotherapy were used to compare scoring for ranking. Dosimetric and biological indexes were analyzed for the plans for a clearly distinguishable group ( n = 7) and a similar group ( n = 12), using treatment plan verification software that we developed. The quality factor ( QF) of our support software for treatment decisions was consistent with the final treatment plan for the clearly distinguishable group (average QF = 1.202, 100% match rate, n = 7) and the similar group (average QF = 1.058, 33% match rate, n = 12). Therefore, we propose a normal tissue complication probability (NTCP) based on the plan scoring index for verification of different plans for personalized treatment-plan selection. Scoring using the new QF showed a 100% match rate (average NTCP QF = 1.0420). The NTCP-based new QF scoring method was adequate for obtaining biological verification quality and organ risk saving using the treatment-planning decision-support software we developed for prostate cancer.

  2. A new formula for normal tissue complication probability (NTCP) as a function of equivalent uniform dose (EUD).

    Science.gov (United States)

    Luxton, Gary; Keall, Paul J; King, Christopher R

    2008-01-07

    To facilitate the use of biological outcome modeling for treatment planning, an exponential function is introduced as a simpler equivalent to the Lyman formula for calculating normal tissue complication probability (NTCP). The single parameter of the exponential function is chosen to reproduce the Lyman calculation to within approximately 0.3%, and thus enable easy conversion of data contained in empirical fits of Lyman parameters for organs at risk (OARs). Organ parameters for the new formula are given in terms of Lyman model m and TD(50), and conversely m and TD(50) are expressed in terms of the parameters of the new equation. The role of the Lyman volume-effect parameter n is unchanged from its role in the Lyman model. For a non-homogeneously irradiated OAR, an equation relates d(ref), n, v(eff) and the Niemierko equivalent uniform dose (EUD), where d(ref) and v(eff) are the reference dose and effective fractional volume of the Kutcher-Burman reduction algorithm (i.e. the LKB model). It follows in the LKB model that uniform EUD irradiation of an OAR results in the same NTCP as the original non-homogeneous distribution. The NTCP equation is therefore represented as a function of EUD. The inverse equation expresses EUD as a function of NTCP and is used to generate a table of EUD versus normal tissue complication probability for the Emami-Burman parameter fits as well as for OAR parameter sets from more recent data.

  3. A new formula for normal tissue complication probability (NTCP) as a function of equivalent uniform dose (EUD)

    International Nuclear Information System (INIS)

    Luxton, Gary; Keall, Paul J; King, Christopher R

    2008-01-01

    To facilitate the use of biological outcome modeling for treatment planning, an exponential function is introduced as a simpler equivalent to the Lyman formula for calculating normal tissue complication probability (NTCP). The single parameter of the exponential function is chosen to reproduce the Lyman calculation to within ∼0.3%, and thus enable easy conversion of data contained in empirical fits of Lyman parameters for organs at risk (OARs). Organ parameters for the new formula are given in terms of Lyman model m and TD 50 , and conversely m and TD 50 are expressed in terms of the parameters of the new equation. The role of the Lyman volume-effect parameter n is unchanged from its role in the Lyman model. For a non-homogeneously irradiated OAR, an equation relates d ref , n, v eff and the Niemierko equivalent uniform dose (EUD), where d ref and v eff are the reference dose and effective fractional volume of the Kutcher-Burman reduction algorithm (i.e. the LKB model). It follows in the LKB model that uniform EUD irradiation of an OAR results in the same NTCP as the original non-homogeneous distribution. The NTCP equation is therefore represented as a function of EUD. The inverse equation expresses EUD as a function of NTCP and is used to generate a table of EUD versus normal tissue complication probability for the Emami-Burman parameter fits as well as for OAR parameter sets from more recent data

  4. Normal tissue complication probabilities: dependence on choice of biological model and dose-volume histogram reduction scheme

    International Nuclear Information System (INIS)

    Moiseenko, Vitali; Battista, Jerry; Van Dyk, Jake

    2000-01-01

    Purpose: To evaluate the impact of dose-volume histogram (DVH) reduction schemes and models of normal tissue complication probability (NTCP) on ranking of radiation treatment plans. Methods and Materials: Data for liver complications in humans and for spinal cord in rats were used to derive input parameters of four different NTCP models. DVH reduction was performed using two schemes: 'effective volume' and 'preferred Lyman'. DVHs for competing treatment plans were derived from a sample DVH by varying dose uniformity in a high dose region so that the obtained cumulative DVHs intersected. Treatment plans were ranked according to the calculated NTCP values. Results: Whenever the preferred Lyman scheme was used to reduce the DVH, competing plans were indistinguishable as long as the mean dose was constant. The effective volume DVH reduction scheme did allow us to distinguish between these competing treatment plans. However, plan ranking depended on the radiobiological model used and its input parameters. Conclusions: Dose escalation will be a significant part of radiation treatment planning using new technologies, such as 3-D conformal radiotherapy and tomotherapy. Such dose escalation will depend on how the dose distributions in organs at risk are interpreted in terms of expected complication probabilities. The present study indicates considerable variability in predicted NTCP values because of the methods used for DVH reduction and radiobiological models and their input parameters. Animal studies and collection of standardized clinical data are needed to ascertain the effects of non-uniform dose distributions and to test the validity of the models currently in use

  5. Normal tissue complication probability modeling of radiation-induced hypothyroidism after head-and-neck radiation therapy.

    Science.gov (United States)

    Bakhshandeh, Mohsen; Hashemi, Bijan; Mahdavi, Seied Rabi Mehdi; Nikoofar, Alireza; Vasheghani, Maryam; Kazemnejad, Anoshirvan

    2013-02-01

    To determine the dose-response relationship of the thyroid for radiation-induced hypothyroidism in head-and-neck radiation therapy, according to 6 normal tissue complication probability models, and to find the best-fit parameters of the models. Sixty-five patients treated with primary or postoperative radiation therapy for various cancers in the head-and-neck region were prospectively evaluated. Patient serum samples (tri-iodothyronine, thyroxine, thyroid-stimulating hormone [TSH], free tri-iodothyronine, and free thyroxine) were measured before and at regular time intervals until 1 year after the completion of radiation therapy. Dose-volume histograms (DVHs) of the patients' thyroid gland were derived from their computed tomography (CT)-based treatment planning data. Hypothyroidism was defined as increased TSH (subclinical hypothyroidism) or increased TSH in combination with decreased free thyroxine and thyroxine (clinical hypothyroidism). Thyroid DVHs were converted to 2 Gy/fraction equivalent doses using the linear-quadratic formula with α/β = 3 Gy. The evaluated models included the following: Lyman with the DVH reduced to the equivalent uniform dose (EUD), known as LEUD; Logit-EUD; mean dose; relative seriality; individual critical volume; and population critical volume models. The parameters of the models were obtained by fitting the patients' data using a maximum likelihood analysis method. The goodness of fit of the models was determined by the 2-sample Kolmogorov-Smirnov test. Ranking of the models was made according to Akaike's information criterion. Twenty-nine patients (44.6%) experienced hypothyroidism. None of the models was rejected according to the evaluation of the goodness of fit. The mean dose model was ranked as the best model on the basis of its Akaike's information criterion value. The D(50) estimated from the models was approximately 44 Gy. The implemented normal tissue complication probability models showed a parallel architecture for the

  6. Normal Tissue Complication Probability Modeling of Radiation-Induced Hypothyroidism After Head-and-Neck Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Bakhshandeh, Mohsen [Department of Medical Physics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Hashemi, Bijan, E-mail: bhashemi@modares.ac.ir [Department of Medical Physics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Mahdavi, Seied Rabi Mehdi [Department of Medical Physics, Faculty of Medical Sciences, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Nikoofar, Alireza; Vasheghani, Maryam [Department of Radiation Oncology, Hafte-Tir Hospital, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Kazemnejad, Anoshirvan [Department of Biostatistics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of)

    2013-02-01

    Purpose: To determine the dose-response relationship of the thyroid for radiation-induced hypothyroidism in head-and-neck radiation therapy, according to 6 normal tissue complication probability models, and to find the best-fit parameters of the models. Methods and Materials: Sixty-five patients treated with primary or postoperative radiation therapy for various cancers in the head-and-neck region were prospectively evaluated. Patient serum samples (tri-iodothyronine, thyroxine, thyroid-stimulating hormone [TSH], free tri-iodothyronine, and free thyroxine) were measured before and at regular time intervals until 1 year after the completion of radiation therapy. Dose-volume histograms (DVHs) of the patients' thyroid gland were derived from their computed tomography (CT)-based treatment planning data. Hypothyroidism was defined as increased TSH (subclinical hypothyroidism) or increased TSH in combination with decreased free thyroxine and thyroxine (clinical hypothyroidism). Thyroid DVHs were converted to 2 Gy/fraction equivalent doses using the linear-quadratic formula with {alpha}/{beta} = 3 Gy. The evaluated models included the following: Lyman with the DVH reduced to the equivalent uniform dose (EUD), known as LEUD; Logit-EUD; mean dose; relative seriality; individual critical volume; and population critical volume models. The parameters of the models were obtained by fitting the patients' data using a maximum likelihood analysis method. The goodness of fit of the models was determined by the 2-sample Kolmogorov-Smirnov test. Ranking of the models was made according to Akaike's information criterion. Results: Twenty-nine patients (44.6%) experienced hypothyroidism. None of the models was rejected according to the evaluation of the goodness of fit. The mean dose model was ranked as the best model on the basis of its Akaike's information criterion value. The D{sub 50} estimated from the models was approximately 44 Gy. Conclusions: The implemented

  7. Hypothyroidism after primary radiotherapy for head and neck squamous cell carcinoma: Normal tissue complication probability modeling with latent time correction

    International Nuclear Information System (INIS)

    Rønjom, Marianne Feen; Brink, Carsten; Bentzen, Søren M.; Hegedüs, Laszlo; Overgaard, Jens; Johansen, Jørgen

    2013-01-01

    Background and purpose: To develop a normal tissue complication probability (NTCP) model of radiation-induced biochemical hypothyroidism (HT) after primary radiotherapy for head and neck squamous cell carcinoma (HNSCC) with adjustment for latency and clinical risk factors. Patients and methods: Patients with HNSCC receiving definitive radiotherapy with 66–68 Gy without surgery were followed up with serial post-treatment thyrotropin (TSH) assessment. HT was defined as TSH >4.0 mU/l. Data were analyzed with both a logistic and a mixture model (correcting for latency) to determine risk factors for HT and develop an NTCP model based on mean thyroid dose (MTD) and thyroid volume. Results: 203 patients were included. Median follow-up: 25.1 months. Five-year estimated risk of HT was 25.6%. In the mixture model, the only independent risk factors for HT were thyroid volume (cm 3 ) (OR = 0.75 [95% CI: 0.64–0.85], p 3 , respectively. Conclusions: Comparing the logistic and mixture models demonstrates the importance of latent-time correction in NTCP-modeling. Thyroid dose constraints in treatment planning should be individualized based on thyroid volume

  8. Multivariate normal tissue complication probability modeling of gastrointestinal toxicity after external beam radiotherapy for localized prostate cancer

    International Nuclear Information System (INIS)

    Cella, Laura; D’Avino, Vittoria; Liuzzi, Raffaele; Conson, Manuel; Doria, Francesca; Faiella, Adriana; Loffredo, Filomena; Salvatore, Marco; Pacelli, Roberto

    2013-01-01

    The risk of radio-induced gastrointestinal (GI) complications is affected by several factors other than the dose to the rectum such as patient characteristics, hormonal or antihypertensive therapy, and acute rectal toxicity. Purpose of this work is to study clinical and dosimetric parameters impacting on late GI toxicity after prostate external beam radiotherapy (RT) and to establish multivariate normal tissue complication probability (NTCP) model for radiation-induced GI complications. A total of 57 men who had undergone definitive RT for prostate cancer were evaluated for GI events classified using the RTOG/EORTC scoring system. Their median age was 73 years (range 53–85). The patients were assessed for GI toxicity before, during, and periodically after RT completion. Several clinical variables along with rectum dose-volume parameters (Vx) were collected and their correlation to GI toxicity was analyzed by Spearman’s rank correlation coefficient (Rs). Multivariate logistic regression method using resampling techniques was applied to select model order and parameters for NTCP modeling. Model performance was evaluated through the area under the receiver operating characteristic curve (AUC). At a median follow-up of 30 months, 37% (21/57) patients developed G1-2 acute GI events while 33% (19/57) were diagnosed with G1-2 late GI events. An NTCP model for late mild/moderate GI toxicity based on three variables including V65 (OR = 1.03), antihypertensive and/or anticoagulant (AH/AC) drugs (OR = 0.24), and acute GI toxicity (OR = 4.3) was selected as the most predictive model (Rs = 0.47, p < 0.001; AUC = 0.79). This three-variable model outperforms the logistic model based on V65 only (Rs = 0.28, p < 0.001; AUC = 0.69). We propose a logistic NTCP model for late GI toxicity considering not only rectal irradiation dose but also clinical patient-specific factors. Accordingly, the risk of G1-2 late GI increases as V65 increases, it is higher for patients experiencing

  9. Design and Selection of Machine Learning Methods Using Radiomics and Dosiomics for Normal Tissue Complication Probability Modeling of Xerostomia.

    Science.gov (United States)

    Gabryś, Hubert S; Buettner, Florian; Sterzing, Florian; Hauswald, Henrik; Bangert, Mark

    2018-01-01

    The purpose of this study is to investigate whether machine learning with dosiomic, radiomic, and demographic features allows for xerostomia risk assessment more precise than normal tissue complication probability (NTCP) models based on the mean radiation dose to parotid glands. A cohort of 153 head-and-neck cancer patients was used to model xerostomia at 0-6 months (early), 6-15 months (late), 15-24 months (long-term), and at any time (a longitudinal model) after radiotherapy. Predictive power of the features was evaluated by the area under the receiver operating characteristic curve (AUC) of univariate logistic regression models. The multivariate NTCP models were tuned and tested with single and nested cross-validation, respectively. We compared predictive performance of seven classification algorithms, six feature selection methods, and ten data cleaning/class balancing techniques using the Friedman test and the Nemenyi post hoc analysis. NTCP models based on the parotid mean dose failed to predict xerostomia (AUCs  0.85), dose gradients in the right-left (AUCs > 0.78), and the anterior-posterior (AUCs > 0.72) direction. Multivariate models of long-term xerostomia were typically based on the parotid volume, the parotid eccentricity, and the dose-volume histogram (DVH) spread with the generalization AUCs ranging from 0.74 to 0.88. On average, support vector machines and extra-trees were the top performing classifiers, whereas the algorithms based on logistic regression were the best choice for feature selection. We found no advantage in using data cleaning or class balancing methods. We demonstrated that incorporation of organ- and dose-shape descriptors is beneficial for xerostomia prediction in highly conformal radiotherapy treatments. Due to strong reliance on patient-specific, dose-independent factors, our results underscore the need for development of personalized data-driven risk profiles for NTCP models of xerostomia. The facilitated

  10. Methods for Reducing Normal Tissue Complication Probabilities in Oropharyngeal Cancer: Dose Reduction or Planning Target Volume Elimination

    Energy Technology Data Exchange (ETDEWEB)

    Samuels, Stuart E.; Eisbruch, Avraham; Vineberg, Karen; Lee, Jae; Lee, Choonik; Matuszak, Martha M.; Ten Haken, Randall K.; Brock, Kristy K., E-mail: kbrock@med.umich.edu

    2016-11-01

    Purpose: Strategies to reduce the toxicities of head and neck radiation (ie, dysphagia [difficulty swallowing] and xerostomia [dry mouth]) are currently underway. However, the predicted benefit of dose and planning target volume (PTV) reduction strategies is unknown. The purpose of the present study was to compare the normal tissue complication probabilities (NTCP) for swallowing and salivary structures in standard plans (70 Gy [P70]), dose-reduced plans (60 Gy [P60]), and plans eliminating the PTV margin. Methods and Materials: A total of 38 oropharyngeal cancer (OPC) plans were analyzed. Standard organ-sparing volumetric modulated arc therapy plans (P70) were created and then modified by eliminating the PTVs and treating the clinical tumor volumes (CTVs) only (C70) or maintaining the PTV but reducing the dose to 60 Gy (P60). NTCP dose models for the pharyngeal constrictors, glottis/supraglottic larynx, parotid glands (PGs), and submandibular glands (SMGs) were analyzed. The minimal clinically important benefit was defined as a mean change in NTCP of >5%. The P70 NTCP thresholds and overlap percentages of the organs at risk with the PTVs (56-59 Gy, vPTV{sub 56}) were evaluated to identify the predictors for NTCP improvement. Results: With the P60 plans, only the ipsilateral PG (iPG) benefited (23.9% vs 16.2%; P<.01). With the C70 plans, only the iPG (23.9% vs 17.5%; P<.01) and contralateral SMG (cSMG) (NTCP 32.1% vs 22.9%; P<.01) benefited. An iPG NTCP threshold of 20% and 30% predicted NTCP benefits for the P60 and C70 plans, respectively (P<.001). A cSMG NTCP threshold of 30% predicted for an NTCP benefit with the C70 plans (P<.001). Furthermore, for the iPG, a vPTV{sub 56} >13% predicted benefit with P60 (P<.001) and C70 (P=.002). For the cSMG, a vPTV{sub 56} >22% predicted benefit with C70 (P<.01). Conclusions: PTV elimination and dose-reduction lowered the NTCP of the iPG, and PTV elimination lowered the NTCP of the cSMG. NTCP thresholds and the

  11. Design and Selection of Machine Learning Methods Using Radiomics and Dosiomics for Normal Tissue Complication Probability Modeling of Xerostomia

    Directory of Open Access Journals (Sweden)

    Hubert S. Gabryś

    2018-03-01

    Full Text Available PurposeThe purpose of this study is to investigate whether machine learning with dosiomic, radiomic, and demographic features allows for xerostomia risk assessment more precise than normal tissue complication probability (NTCP models based on the mean radiation dose to parotid glands.Material and methodsA cohort of 153 head-and-neck cancer patients was used to model xerostomia at 0–6 months (early, 6–15 months (late, 15–24 months (long-term, and at any time (a longitudinal model after radiotherapy. Predictive power of the features was evaluated by the area under the receiver operating characteristic curve (AUC of univariate logistic regression models. The multivariate NTCP models were tuned and tested with single and nested cross-validation, respectively. We compared predictive performance of seven classification algorithms, six feature selection methods, and ten data cleaning/class balancing techniques using the Friedman test and the Nemenyi post hoc analysis.ResultsNTCP models based on the parotid mean dose failed to predict xerostomia (AUCs < 0.60. The most informative predictors were found for late and long-term xerostomia. Late xerostomia correlated with the contralateral dose gradient in the anterior–posterior (AUC = 0.72 and the right–left (AUC = 0.68 direction, whereas long-term xerostomia was associated with parotid volumes (AUCs > 0.85, dose gradients in the right–left (AUCs > 0.78, and the anterior–posterior (AUCs > 0.72 direction. Multivariate models of long-term xerostomia were typically based on the parotid volume, the parotid eccentricity, and the dose–volume histogram (DVH spread with the generalization AUCs ranging from 0.74 to 0.88. On average, support vector machines and extra-trees were the top performing classifiers, whereas the algorithms based on logistic regression were the best choice for feature selection. We found no advantage in using data cleaning or class balancing

  12. The Benefits of Including Clinical Factors in Rectal Normal Tissue Complication Probability Modeling After Radiotherapy for Prostate Cancer

    International Nuclear Information System (INIS)

    Defraene, Gilles; Van den Bergh, Laura; Al-Mamgani, Abrahim; Haustermans, Karin; Heemsbergen, Wilma; Van den Heuvel, Frank; Lebesque, Joos V.

    2012-01-01

    Purpose: To study the impact of clinical predisposing factors on rectal normal tissue complication probability modeling using the updated results of the Dutch prostate dose-escalation trial. Methods and Materials: Toxicity data of 512 patients (conformally treated to 68 Gy [n = 284] and 78 Gy [n = 228]) with complete follow-up at 3 years after radiotherapy were studied. Scored end points were rectal bleeding, high stool frequency, and fecal incontinence. Two traditional dose-based models (Lyman-Kutcher-Burman (LKB) and Relative Seriality (RS) and a logistic model were fitted using a maximum likelihood approach. Furthermore, these model fits were improved by including the most significant clinical factors. The area under the receiver operating characteristic curve (AUC) was used to compare the discriminating ability of all fits. Results: Including clinical factors significantly increased the predictive power of the models for all end points. In the optimal LKB, RS, and logistic models for rectal bleeding and fecal incontinence, the first significant (p = 0.011–0.013) clinical factor was “previous abdominal surgery.” As second significant (p = 0.012–0.016) factor, “cardiac history” was included in all three rectal bleeding fits, whereas including “diabetes” was significant (p = 0.039–0.048) in fecal incontinence modeling but only in the LKB and logistic models. High stool frequency fits only benefitted significantly (p = 0.003–0.006) from the inclusion of the baseline toxicity score. For all models rectal bleeding fits had the highest AUC (0.77) where it was 0.63 and 0.68 for high stool frequency and fecal incontinence, respectively. LKB and logistic model fits resulted in similar values for the volume parameter. The steepness parameter was somewhat higher in the logistic model, also resulting in a slightly lower D 50 . Anal wall DVHs were used for fecal incontinence, whereas anorectal wall dose best described the other two endpoints. Conclusions

  13. The Benefits of Including Clinical Factors in Rectal Normal Tissue Complication Probability Modeling After Radiotherapy for Prostate Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Defraene, Gilles, E-mail: gilles.defraene@uzleuven.be [Radiation Oncology Department, University Hospitals Leuven, Leuven (Belgium); Van den Bergh, Laura [Radiation Oncology Department, University Hospitals Leuven, Leuven (Belgium); Al-Mamgani, Abrahim [Department of Radiation Oncology, Erasmus Medical Center - Daniel den Hoed Cancer Center, Rotterdam (Netherlands); Haustermans, Karin [Radiation Oncology Department, University Hospitals Leuven, Leuven (Belgium); Heemsbergen, Wilma [Netherlands Cancer Institute - Antoni van Leeuwenhoek Hospital, Amsterdam (Netherlands); Van den Heuvel, Frank [Radiation Oncology Department, University Hospitals Leuven, Leuven (Belgium); Lebesque, Joos V. [Netherlands Cancer Institute - Antoni van Leeuwenhoek Hospital, Amsterdam (Netherlands)

    2012-03-01

    Purpose: To study the impact of clinical predisposing factors on rectal normal tissue complication probability modeling using the updated results of the Dutch prostate dose-escalation trial. Methods and Materials: Toxicity data of 512 patients (conformally treated to 68 Gy [n = 284] and 78 Gy [n = 228]) with complete follow-up at 3 years after radiotherapy were studied. Scored end points were rectal bleeding, high stool frequency, and fecal incontinence. Two traditional dose-based models (Lyman-Kutcher-Burman (LKB) and Relative Seriality (RS) and a logistic model were fitted using a maximum likelihood approach. Furthermore, these model fits were improved by including the most significant clinical factors. The area under the receiver operating characteristic curve (AUC) was used to compare the discriminating ability of all fits. Results: Including clinical factors significantly increased the predictive power of the models for all end points. In the optimal LKB, RS, and logistic models for rectal bleeding and fecal incontinence, the first significant (p = 0.011-0.013) clinical factor was 'previous abdominal surgery.' As second significant (p = 0.012-0.016) factor, 'cardiac history' was included in all three rectal bleeding fits, whereas including 'diabetes' was significant (p = 0.039-0.048) in fecal incontinence modeling but only in the LKB and logistic models. High stool frequency fits only benefitted significantly (p = 0.003-0.006) from the inclusion of the baseline toxicity score. For all models rectal bleeding fits had the highest AUC (0.77) where it was 0.63 and 0.68 for high stool frequency and fecal incontinence, respectively. LKB and logistic model fits resulted in similar values for the volume parameter. The steepness parameter was somewhat higher in the logistic model, also resulting in a slightly lower D{sub 50}. Anal wall DVHs were used for fecal incontinence, whereas anorectal wall dose best described the other two endpoints

  14. Prediction of radiation-induced liver disease by Lyman normal-tissue complication probability model in three-dimensional conformal radiation therapy for primary liver carcinoma

    International Nuclear Information System (INIS)

    Xu ZhiYong; Liang Shixiong; Zhu Ji; Zhu Xiaodong; Zhao Jiandong; Lu Haijie; Yang Yunli; Chen Long; Wang Anyu; Fu Xiaolong; Jiang Guoliang

    2006-01-01

    Purpose: To describe the probability of RILD by application of the Lyman-Kutcher-Burman normal-tissue complication (NTCP) model for primary liver carcinoma (PLC) treated with hypofractionated three-dimensional conformal radiotherapy (3D-CRT). Methods and Materials: A total of 109 PLC patients treated by 3D-CRT were followed for RILD. Of these patients, 93 were in liver cirrhosis of Child-Pugh Grade A, and 16 were in Child-Pugh Grade B. The Michigan NTCP model was used to predict the probability of RILD, and then the modified Lyman NTCP model was generated for Child-Pugh A and Child-Pugh B patients by maximum-likelihood analysis. Results: Of all patients, 17 developed RILD in which 8 were of Child-Pugh Grade A, and 9 were of Child-Pugh Grade B. The prediction of RILD by the Michigan model was underestimated for PLC patients. The modified n, m, TD 5 (1) were 1.1, 0.28, and 40.5 Gy and 0.7, 0.43, and 23 Gy for patients with Child-Pugh A and B, respectively, which yielded better estimations of RILD probability. The hepatic tolerable doses (TD 5 ) would be MDTNL of 21 Gy and 6 Gy, respectively, for Child-Pugh A and B patients. Conclusions: The Michigan model was probably not fit to predict RILD in PLC patients. A modified Lyman NTCP model for RILD was recommended

  15. Normal Tissue Complication Probability Estimation by the Lyman-Kutcher-Burman Method Does Not Accurately Predict Spinal Cord Tolerance to Stereotactic Radiosurgery

    International Nuclear Information System (INIS)

    Daly, Megan E.; Luxton, Gary; Choi, Clara Y.H.; Gibbs, Iris C.; Chang, Steven D.; Adler, John R.; Soltys, Scott G.

    2012-01-01

    Purpose: To determine whether normal tissue complication probability (NTCP) analyses of the human spinal cord by use of the Lyman-Kutcher-Burman (LKB) model, supplemented by linear–quadratic modeling to account for the effect of fractionation, predict the risk of myelopathy from stereotactic radiosurgery (SRS). Methods and Materials: From November 2001 to July 2008, 24 spinal hemangioblastomas in 17 patients were treated with SRS. Of the tumors, 17 received 1 fraction with a median dose of 20 Gy (range, 18–30 Gy) and 7 received 20 to 25 Gy in 2 or 3 sessions, with cord maximum doses of 22.7 Gy (range, 17.8–30.9 Gy) and 22.0 Gy (range, 20.2–26.6 Gy), respectively. By use of conventional values for α/β, volume parameter n, 50% complication probability dose TD 50 , and inverse slope parameter m, a computationally simplified implementation of the LKB model was used to calculate the biologically equivalent uniform dose and NTCP for each treatment. Exploratory calculations were performed with alternate values of α/β and n. Results: In this study 1 case (4%) of myelopathy occurred. The LKB model using radiobiological parameters from Emami and the logistic model with parameters from Schultheiss overestimated complication rates, predicting 13 complications (54%) and 18 complications (75%), respectively. An increase in the volume parameter (n), to assume greater parallel organization, improved the predictive value of the models. Maximum-likelihood LKB fitting of α/β and n yielded better predictions (0.7 complications), with n = 0.023 and α/β = 17.8 Gy. Conclusions: The spinal cord tolerance to the dosimetry of SRS is higher than predicted by the LKB model using any set of accepted parameters. Only a high α/β value in the LKB model and only a large volume effect in the logistic model with Schultheiss data could explain the low number of complications observed. This finding emphasizes that radiobiological models traditionally used to estimate spinal cord NTCP

  16. Normal tissue complication probability model parameter estimation for xerostomia in head and neck cancer patients based on scintigraphy and quality of life assessments

    International Nuclear Information System (INIS)

    Lee, Tsair-Fwu; Chao, Pei-Ju; Wang, Hung-Yu; Hsu, Hsuan-Chih; Chang, PaoShu; Chen, Wen-Cheng

    2012-01-01

    With advances in modern radiotherapy (RT), many patients with head and neck (HN) cancer can be effectively cured. However, xerostomia is a common complication in patients after RT for HN cancer. The purpose of this study was to use the Lyman–Kutcher–Burman (LKB) model to derive parameters for the normal tissue complication probability (NTCP) for xerostomia based on scintigraphy assessments and quality of life (QoL) questionnaires. We performed validation tests of the Quantitative Analysis of Normal Tissue Effects in the Clinic (QUANTEC) guidelines against prospectively collected QoL and salivary scintigraphic data. Thirty-one patients with HN cancer were enrolled. Salivary excretion factors (SEFs) measured by scintigraphy and QoL data from self-reported questionnaires were used for NTCP modeling to describe the incidence of grade 3 + xerostomia. The NTCP parameters estimated from the QoL and SEF datasets were compared. Model performance was assessed using Pearson’s chi-squared test, Nagelkerke’s R 2 , the area under the receiver operating characteristic curve, and the Hosmer–Lemeshow test. The negative predictive value (NPV) was checked for the rate of correctly predicting the lack of incidence. Pearson’s chi-squared test was used to test the goodness of fit and association. Using the LKB NTCP model and assuming n=1, the dose for uniform irradiation of the whole or partial volume of the parotid gland that results in 50% probability of a complication (TD 50 ) and the slope of the dose–response curve (m) were determined from the QoL and SEF datasets, respectively. The NTCP-fitted parameters for local disease were TD 50 =43.6 Gy and m=0.18 with the SEF data, and TD 50 =44.1 Gy and m=0.11 with the QoL data. The rate of grade 3 + xerostomia for treatment plans meeting the QUANTEC guidelines was specifically predicted, with a NPV of 100%, using either the QoL or SEF dataset. Our study shows the agreement between the NTCP parameter modeling based on SEF and

  17. Normal tissue complication probability model parameter estimation for xerostomia in head and neck cancer patients based on scintigraphy and quality of life assessments

    Science.gov (United States)

    2012-01-01

    Background With advances in modern radiotherapy (RT), many patients with head and neck (HN) cancer can be effectively cured. However, xerostomia is a common complication in patients after RT for HN cancer. The purpose of this study was to use the Lyman–Kutcher–Burman (LKB) model to derive parameters for the normal tissue complication probability (NTCP) for xerostomia based on scintigraphy assessments and quality of life (QoL) questionnaires. We performed validation tests of the Quantitative Analysis of Normal Tissue Effects in the Clinic (QUANTEC) guidelines against prospectively collected QoL and salivary scintigraphic data. Methods Thirty-one patients with HN cancer were enrolled. Salivary excretion factors (SEFs) measured by scintigraphy and QoL data from self-reported questionnaires were used for NTCP modeling to describe the incidence of grade 3+ xerostomia. The NTCP parameters estimated from the QoL and SEF datasets were compared. Model performance was assessed using Pearson’s chi-squared test, Nagelkerke’s R2, the area under the receiver operating characteristic curve, and the Hosmer–Lemeshow test. The negative predictive value (NPV) was checked for the rate of correctly predicting the lack of incidence. Pearson’s chi-squared test was used to test the goodness of fit and association. Results Using the LKB NTCP model and assuming n=1, the dose for uniform irradiation of the whole or partial volume of the parotid gland that results in 50% probability of a complication (TD50) and the slope of the dose–response curve (m) were determined from the QoL and SEF datasets, respectively. The NTCP-fitted parameters for local disease were TD50=43.6 Gy and m=0.18 with the SEF data, and TD50=44.1 Gy and m=0.11 with the QoL data. The rate of grade 3+ xerostomia for treatment plans meeting the QUANTEC guidelines was specifically predicted, with a NPV of 100%, using either the QoL or SEF dataset. Conclusions Our study shows the agreement between the NTCP

  18. Normal tissue complication probability model parameter estimation for xerostomia in head and neck cancer patients based on scintigraphy and quality of life assessments

    Directory of Open Access Journals (Sweden)

    Lee Tsair-Fwu

    2012-12-01

    Full Text Available Abstract Background With advances in modern radiotherapy (RT, many patients with head and neck (HN cancer can be effectively cured. However, xerostomia is a common complication in patients after RT for HN cancer. The purpose of this study was to use the Lyman–Kutcher–Burman (LKB model to derive parameters for the normal tissue complication probability (NTCP for xerostomia based on scintigraphy assessments and quality of life (QoL questionnaires. We performed validation tests of the Quantitative Analysis of Normal Tissue Effects in the Clinic (QUANTEC guidelines against prospectively collected QoL and salivary scintigraphic data. Methods Thirty-one patients with HN cancer were enrolled. Salivary excretion factors (SEFs measured by scintigraphy and QoL data from self-reported questionnaires were used for NTCP modeling to describe the incidence of grade 3+ xerostomia. The NTCP parameters estimated from the QoL and SEF datasets were compared. Model performance was assessed using Pearson’s chi-squared test, Nagelkerke’s R2, the area under the receiver operating characteristic curve, and the Hosmer–Lemeshow test. The negative predictive value (NPV was checked for the rate of correctly predicting the lack of incidence. Pearson’s chi-squared test was used to test the goodness of fit and association. Results Using the LKB NTCP model and assuming n=1, the dose for uniform irradiation of the whole or partial volume of the parotid gland that results in 50% probability of a complication (TD50 and the slope of the dose–response curve (m were determined from the QoL and SEF datasets, respectively. The NTCP-fitted parameters for local disease were TD50=43.6 Gy and m=0.18 with the SEF data, and TD50=44.1 Gy and m=0.11 with the QoL data. The rate of grade 3+ xerostomia for treatment plans meeting the QUANTEC guidelines was specifically predicted, with a NPV of 100%, using either the QoL or SEF dataset. Conclusions Our study shows the agreement

  19. Increase in tumor control and normal tissue complication probabilities in advanced head-and-neck cancer for dose-escalated intensity-modulated photon and proton therapy

    Directory of Open Access Journals (Sweden)

    Annika eJakobi

    2015-11-01

    Full Text Available Introduction:Presently used radio-chemotherapy regimens result in moderate local control rates for patients with advanced head and neck squamous cell carcinoma (HNSCC. Dose escalation (DE may be an option to improve patient outcome, but may also increase the risk of toxicities in healthy tissue. The presented treatment planning study evaluated the feasibility of two DE levels for advanced HNSCC patients, planned with either intensity-modulated photon therapy (IMXT or proton therapy (IMPT.Materials and Methods:For 45 HNSCC patients, IMXT and IMPT treatment plans were created including DE via a simultaneous integrated boost (SIB in the high-risk volume, while maintaining standard fractionation with 2 Gy per fraction in the remaining target volume. Two DE levels for the SIB were compared: 2.3 Gy and 2.6 Gy. Treatment plan evaluation included assessment of tumor control probabilities (TCP and normal tissue complication probabilities (NTCP.Results:An increase of approximately 10% in TCP was estimated between the DE levels. A pronounced high-dose rim surrounding the SIB volume was identified in IMXT treatment. Compared to IMPT, this extra dose slightly increased the TCP values and to a larger extent the NTCP values. For both modalities, the higher DE level led only to a small increase in NTCP values (mean differences < 2% in all models, except for the risk of aspiration, which increased on average by 8% and 6% with IMXT and IMPT, respectively, but showed a considerable patient dependence. Conclusions:Both DE levels appear applicable to patients with IMXT and IMPT since all calculated NTCP values, except for one, increased only little for the higher DE level. The estimated TCP increase is of relevant magnitude. The higher DE schedule needs to be investigated carefully in the setting of a prospective clinical trial, especially regarding toxicities caused by high local doses that lack a sound dose response description, e.g., ulcers.

  20. Impact of Chemotherapy on Normal Tissue Complication Probability Models of Acute Hematologic Toxicity in Patients Receiving Pelvic Intensity Modulated Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Bazan, Jose G.; Luxton, Gary; Kozak, Margaret M.; Anderson, Eric M.; Hancock, Steven L.; Kapp, Daniel S.; Kidd, Elizabeth A.; Koong, Albert C.; Chang, Daniel T., E-mail: dtchang@stanford.edu

    2013-12-01

    Purpose: To determine how chemotherapy agents affect radiation dose parameters that correlate with acute hematologic toxicity (HT) in patients treated with pelvic intensity modulated radiation therapy (P-IMRT) and concurrent chemotherapy. Methods and Materials: We assessed HT in 141 patients who received P-IMRT for anal, gynecologic, rectal, or prostate cancers, 95 of whom received concurrent chemotherapy. Patients were separated into 4 groups: mitomycin (MMC) + 5-fluorouracil (5FU, 37 of 141), platinum ± 5FU (Cis, 32 of 141), 5FU (26 of 141), and P-IMRT alone (46 of 141). The pelvic bone was contoured as a surrogate for pelvic bone marrow (PBM) and divided into subsites: ilium, lower pelvis, and lumbosacral spine (LSS). The volumes of each region receiving 5-40 Gy were calculated. The endpoint for HT was grade ≥3 (HT3+) leukopenia, neutropenia or thrombocytopenia. Normal tissue complication probability was calculated using the Lyman-Kutcher-Burman model. Logistic regression was used to analyze association between HT3+ and dosimetric parameters. Results: Twenty-six patients experienced HT3+: 10 of 37 (27%) MMC, 14 of 32 (44%) Cis, 2 of 26 (8%) 5FU, and 0 of 46 P-IMRT. PBM dosimetric parameters were correlated with HT3+ in the MMC group but not in the Cis group. LSS dosimetric parameters were well correlated with HT3+ in both the MMC and Cis groups. Constrained optimization (0tissue complication probability curve compared with treatment with Cis. Dose tolerance of PBM and the LSS subsite may be lower for

  1. Normal tissue complication probability modeling for cochlea constraints to avoid causing tinnitus after head-and-neck intensity-modulated radiation therapy

    International Nuclear Information System (INIS)

    Lee, Tsair-Fwu; Yeh, Shyh-An; Chao, Pei-Ju; Chang, Liyun; Chiu, Chien-Liang; Ting, Hui-Min; Wang, Hung-Yu; Huang, Yu-Jie

    2015-01-01

    Radiation-induced tinnitus is a side effect of radiotherapy in the inner ear for cancers of the head and neck. Effective dose constraints for protecting the cochlea are under-reported. The aim of this study is to determine the cochlea dose limitation to avoid causing tinnitus after head-and-neck cancer (HNC) intensity-modulated radiation therapy (IMRT). In total 211 patients with HNC were included; the side effects of radiotherapy were investigated for 422 inner ears in the cohort. Forty-nine of the four hundred and twenty-two samples (11.6 %) developed grade 2+ tinnitus symptoms after IMRT, as diagnosed by a clinician. The Late Effects of Normal Tissues–Subjective, Objective, Management, Analytic (LENT-SOMA) criteria were used for tinnitus evaluation. The logistic and Lyman-Kutcher-Burman (LKB) normal tissue complication probability (NTCP) models were used for the analyses. The NTCP-fitted parameters were TD 50 = 46.31 Gy (95 % CI, 41.46–52.50), γ 50 = 1.27 (95 % CI, 1.02–1.55), and TD 50 = 46.52 Gy (95 % CI, 41.91–53.43), m = 0.35 (95 % CI, 0.30–0.42) for the logistic and LKB models, respectively. The suggested guideline TD 20 for the tolerance dose to produce a 20 % complication rate within a specific period of time was TD 20 = 33.62 Gy (95 % CI, 30.15–38.27) (logistic) and TD 20 = 32.82 Gy (95 % CI, 29.58–37.69) (LKB). To maintain the incidence of grade 2+ tinnitus toxicity <20 % in IMRT, we suggest that the mean dose to the cochlea should be <32 Gy. However, models should not be extrapolated to other patient populations without further verification and should first be confirmed before clinical implementation

  2. Identification of Patient Benefit From Proton Therapy for Advanced Head and Neck Cancer Patients Based on Individual and Subgroup Normal Tissue Complication Probability Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Jakobi, Annika, E-mail: Annika.Jakobi@OncoRay.de [OncoRay-National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden-Rossendorf, Dresden (Germany); Bandurska-Luque, Anna [OncoRay-National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden-Rossendorf, Dresden (Germany); Department of Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden (Germany); Stützer, Kristin; Haase, Robert; Löck, Steffen [OncoRay-National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden-Rossendorf, Dresden (Germany); Wack, Linda-Jacqueline [Section for Biomedical Physics, University Hospital for Radiation Oncology, Eberhard Karls Universät Tübingen (Germany); Mönnich, David [Section for Biomedical Physics, University Hospital for Radiation Oncology, Eberhard Karls Universät Tübingen (Germany); German Cancer Research Center, Heidelberg (Germany); German Cancer Consortium, Tübingen (Germany); Thorwarth, Daniela [Section for Biomedical Physics, University Hospital for Radiation Oncology, Eberhard Karls Universät Tübingen (Germany); and others

    2015-08-01

    Purpose: The purpose of this study was to determine, by treatment plan comparison along with normal tissue complication probability (NTCP) modeling, whether a subpopulation of patients with head and neck squamous cell carcinoma (HNSCC) could be identified that would gain substantial benefit from proton therapy in terms of NTCP. Methods and Materials: For 45 HNSCC patients, intensity modulated radiation therapy (IMRT) was compared to intensity modulated proton therapy (IMPT). Physical dose distributions were evaluated as well as the resulting NTCP values, using modern models for acute mucositis, xerostomia, aspiration, dysphagia, laryngeal edema, and trismus. Patient subgroups were defined based on primary tumor location. Results: Generally, IMPT reduced the NTCP values while keeping similar target coverage for all patients. Subgroup analyses revealed a higher individual reduction of swallowing-related side effects by IMPT for patients with tumors in the upper head and neck area, whereas the risk reduction of acute mucositis was more pronounced in patients with tumors in the larynx region. More patients with tumors in the upper head and neck area had a reduction in NTCP of more than 10%. Conclusions: Subgrouping can help to identify patients who may benefit more than others from the use of IMPT and, thus, can be a useful tool for a preselection of patients in the clinic where there are limited PT resources. Because the individual benefit differs within a subgroup, the relative merits should additionally be evaluated by individual treatment plan comparisons.

  3. Identification of Patient Benefit From Proton Therapy for Advanced Head and Neck Cancer Patients Based on Individual and Subgroup Normal Tissue Complication Probability Analysis

    International Nuclear Information System (INIS)

    Jakobi, Annika; Bandurska-Luque, Anna; Stützer, Kristin; Haase, Robert; Löck, Steffen; Wack, Linda-Jacqueline; Mönnich, David; Thorwarth, Daniela

    2015-01-01

    Purpose: The purpose of this study was to determine, by treatment plan comparison along with normal tissue complication probability (NTCP) modeling, whether a subpopulation of patients with head and neck squamous cell carcinoma (HNSCC) could be identified that would gain substantial benefit from proton therapy in terms of NTCP. Methods and Materials: For 45 HNSCC patients, intensity modulated radiation therapy (IMRT) was compared to intensity modulated proton therapy (IMPT). Physical dose distributions were evaluated as well as the resulting NTCP values, using modern models for acute mucositis, xerostomia, aspiration, dysphagia, laryngeal edema, and trismus. Patient subgroups were defined based on primary tumor location. Results: Generally, IMPT reduced the NTCP values while keeping similar target coverage for all patients. Subgroup analyses revealed a higher individual reduction of swallowing-related side effects by IMPT for patients with tumors in the upper head and neck area, whereas the risk reduction of acute mucositis was more pronounced in patients with tumors in the larynx region. More patients with tumors in the upper head and neck area had a reduction in NTCP of more than 10%. Conclusions: Subgrouping can help to identify patients who may benefit more than others from the use of IMPT and, thus, can be a useful tool for a preselection of patients in the clinic where there are limited PT resources. Because the individual benefit differs within a subgroup, the relative merits should additionally be evaluated by individual treatment plan comparisons

  4. Development of a multivariable normal tissue complication probability (NTCP) model for tube feeding dependence after curative radiotherapy/chemo-radiotherapy in head and neck cancer

    International Nuclear Information System (INIS)

    Wopken, Kim; Bijl, Hendrik P.; Schaaf, Arjen van der; Laan, Hans Paul van der; Chouvalova, Olga; Steenbakkers, Roel J.H.M.; Doornaert, Patricia; Slotman, Ben J.; Oosting, Sjoukje F.; Christianen, Miranda E.M.C.; Laan, Bernard F.A.M. van der; Roodenburg, Jan L.N.; René Leemans, C.; Verdonck-de Leeuw, Irma M.; Langendijk, Johannes A.

    2014-01-01

    Background and purpose: Curative radiotherapy/chemo-radiotherapy for head and neck cancer (HNC) may result in severe acute and late side effects, including tube feeding dependence. The purpose of this prospective cohort study was to develop a multivariable normal tissue complication probability (NTCP) model for tube feeding dependence 6 months (TUBE M6 ) after definitive radiotherapy, radiotherapy plus cetuximab or concurrent chemoradiation based on pre-treatment and treatment characteristics. Materials and methods: The study included 355 patients with HNC. TUBE M6 was scored prospectively in a standard follow-up program. To design the prediction model, the penalized learning method LASSO was used, with TUBE M6 as the endpoint. Results: The prevalence of TUBE M6 was 10.7%. The multivariable model with the best performance consisted of the variables: advanced T-stage, moderate to severe weight loss at baseline, accelerated radiotherapy, chemoradiation, radiotherapy plus cetuximab, the mean dose to the superior and inferior pharyngeal constrictor muscle, to the contralateral parotid gland and to the cricopharyngeal muscle. Conclusions: We developed a multivariable NTCP model for TUBE M6 to identify patients at risk for tube feeding dependence. The dosimetric variables can be used to optimize radiotherapy treatment planning aiming at prevention of tube feeding dependence and to estimate the benefit of new radiation technologies

  5. The effect of 6 and 15 MV on intensity-modulated radiation therapy prostate cancer treatment: plan evaluation, tumour control probability and normal tissue complication probability analysis, and the theoretical risk of secondary induced malignancies

    Science.gov (United States)

    Hussein, M; Aldridge, S; Guerrero Urbano, T; Nisbet, A

    2012-01-01

    Objective The aim of this study was to investigate the effect of 6 and 15-MV photon energies on intensity-modulated radiation therapy (IMRT) prostate cancer treatment plan outcome and to compare the theoretical risks of secondary induced malignancies. Methods Separate prostate cancer IMRT plans were prepared for 6 and 15-MV beams. Organ-equivalent doses were obtained through thermoluminescent dosemeter measurements in an anthropomorphic Aldersen radiation therapy human phantom. The neutron dose contribution at 15 MV was measured using polyallyl-diglycol-carbonate neutron track etch detectors. Risk coefficients from the International Commission on Radiological Protection Report 103 were used to compare the risk of fatal secondary induced malignancies in out-of-field organs and tissues for 6 and 15 MV. For the bladder and the rectum, a comparative evaluation of the risk using three separate models was carried out. Dose–volume parameters for the rectum, bladder and prostate planning target volume were evaluated, as well as normal tissue complication probability (NTCP) and tumour control probability calculations. Results There is a small increased theoretical risk of developing a fatal cancer from 6 MV compared with 15 MV, taking into account all the organs. Dose–volume parameters for the rectum and bladder show that 15 MV results in better volume sparing in the regions below 70 Gy, but the volume exposed increases slightly beyond this in comparison with 6 MV, resulting in a higher NTCP for the rectum of 3.6% vs 3.0% (p=0.166). Conclusion The choice to treat using IMRT at 15 MV should not be excluded, but should be based on risk vs benefit while considering the age and life expectancy of the patient together with the relative risk of radiation-induced cancer and NTCPs. PMID:22010028

  6. Normal Tissue Complication Probability Analysis of Acute Gastrointestinal Toxicity in Cervical Cancer Patients Undergoing Intensity Modulated Radiation Therapy and Concurrent Cisplatin

    International Nuclear Information System (INIS)

    Simpson, Daniel R.; Song, William Y.; Moiseenko, Vitali; Rose, Brent S.; Yashar, Catheryn M.; Mundt, Arno J.; Mell, Loren K.

    2012-01-01

    Purpose: To test the hypothesis that increased bowel radiation dose is associated with acute gastrointestinal (GI) toxicity in cervical cancer patients undergoing concurrent chemotherapy and intensity-modulated radiation therapy (IMRT), using a previously derived normal tissue complication probability (NTCP) model. Methods: Fifty patients with Stage I–III cervical cancer undergoing IMRT and concurrent weekly cisplatin were analyzed. Acute GI toxicity was graded using the Radiation Therapy Oncology Group scale, excluding upper GI events. A logistic model was used to test correlations between acute GI toxicity and bowel dosimetric parameters. The primary objective was to test the association between Grade ≥2 GI toxicity and the volume of bowel receiving ≥45 Gy (V 45 ) using the logistic model. Results: Twenty-three patients (46%) had Grade ≥2 GI toxicity. The mean (SD) V 45 was 143 mL (99). The mean V 45 values for patients with and without Grade ≥2 GI toxicity were 176 vs. 115 mL, respectively. Twenty patients (40%) had V 45 >150 mL. The proportion of patients with Grade ≥2 GI toxicity with and without V 45 >150 mL was 65% vs. 33% (p = 0.03). Logistic model parameter estimates V50 and γ were 161 mL (95% confidence interval [CI] 60–399) and 0.31 (95% CI 0.04–0.63), respectively. On multivariable logistic regression, increased V 45 was associated with an increased odds of Grade ≥2 GI toxicity (odds ratio 2.19 per 100 mL, 95% CI 1.04–4.63, p = 0.04). Conclusions: Our results support the hypothesis that increasing bowel V 45 is correlated with increased GI toxicity in cervical cancer patients undergoing IMRT and concurrent cisplatin. Reducing bowel V 45 could reduce the risk of Grade ≥2 GI toxicity by approximately 50% per 100 mL of bowel spared.

  7. Normal tissue complication probability: Does simultaneous integrated boost intensity-modulated radiotherapy score over other techniques in treatment of prostate adenocarcinoma

    Directory of Open Access Journals (Sweden)

    Jothy Basu K

    2009-01-01

    Full Text Available Aim: The main objective of this study was to analyze the radiobiological effect of different treatment strategies on high-risk prostate adenocarcinoma. Materials and Methods: Ten cases of high-risk prostate adenocarcinoma were selected for this dosimetric study. Four different treatment strategies used for treating prostate cancer were compared. Conventional four-field box technique covering prostate and nodal volumes followed by three-field conformal boost (3D + 3DCRT, four-field box technique followed by intensity-modulated radiotherapy (IMRT boost (3D + IMRT, IMRT followed by IMRT boost (IMRT + IMRT, and simultaneous integrated boost IMRT (SIBIMRT were compared in terms of tumor control probability (TCP and normal tissue complication probability (NTCP. The dose prescription except for SIBIMRT was 45 Gy in 25 fractions for the prostate and nodal volumes in the initial phase and 27 Gy in 15 fractions for the prostate in the boost phase. For SIBIMRT, equivalent doses were calculated using biologically equivalent dose assuming the α/β ratio of 1.5 Gy with a dose prescription of 60.75 Gy for the gross tumor volume (GTV and 45 Gy for the clinical target volume in 25 fractions. IMRT plans were made with 15-MV equispaced seven coplanar fields. NTCP was calculated using the Lyman-Kutcher-Burman (LKB model. Results: An NTCP of 10.7 ± 0.99%, 8.36 ± 0.66%, 6.72 ± 0.85%, and 1.45 ± 0.11% for the bladder and 14.9 ± 0.99%, 14.04 ± 0.66%, 11.38 ± 0.85%, 5.12 ± 0.11% for the rectum was seen with 3D + 3DCRT, 3D + IMRT, IMRT + IMRT, and SIBIMRT respectively. Conclusions: SIBIMRT had the least NTCP over all other strategies with a reduced treatment time (3 weeks less. It should be the technique of choice for dose escalation in prostate carcinoma.

  8. Probable biofilm formation in the cheek as a complication of soft tissue filler resulting from improper endodontic treatment of tooth 16

    Directory of Open Access Journals (Sweden)

    Marusza W

    2012-03-01

    Full Text Available Wojciech Marusza1, Grazyna Mlynarczyk2, Romuald Olszanski3, Irina Netsvyetayeva2, Michael Obrowski1, Tommaso Iannitti4, Beniamino Palmieri51Academy of Face Sculpturing, 2Department of Microbiology, Medical University of Warsaw, 3Military Institute of Health Services, Warsaw, Poland; 4Department of Physiology, School of Medicine, University of Kentucky Medical Center, KY, USA; 5Department of General Surgery and Surgical Specialties, University of Modena and Reggio Emilia Medical School, Surgical Clinic, Modena, ItalyAbstract: Injectable filling agents offer the promise of a better appearance without surgery and, among them, hyaluronic acid is the most commonly used. Although complications are rare, it is necessary to know the possible side effects and complications in order to be prepared for their management. That is why many researchers have been focusing on the interactions between hyaluronic acid and pathogens, inflammatory mediators, the immune system, and markers of oxidative stress to achieve efficient drug delivery, given that hyaluronic acid has widening applications in the field of nanomedicine. Here we report the case of a 37-year-old female patient who returned to our clinic with an abscess in her left cheek 3 months after a deep injection of 1 mL of stabilized hyaluronic acid in both cheeks. Steroid and antibiotic therapy was initiated without success, and abscess drainage was performed. Extraction of tooth 16 was performed 11 days after insertion of drains into the abscess. Laboratory blood tests showed acute inflammation of presumed bacterial etiology. Microbiological examination of pus was negative. Bacterial cultures were found in the extracted tooth. After antibiotic therapy, a complete reversal of the pathological process was observed. The present report highlights the need to assess periodontal problems prior to any aesthetic facial treatment. Analyses of further case reports and clinical studies are necessary to understand

  9. Calculation of cranial nerve complication probability for acoustic neuroma radiosurgery

    International Nuclear Information System (INIS)

    Meeks, Sanford L.; Buatti, John M.; Foote, Kelly D.; Friedman, William A.; Bova, Francis J.

    2000-01-01

    Purpose: Estimations of complications from stereotactic radiosurgery usually rely simply on dose-volume or dose-diameter isoeffect curves. Due to the sparse clinical data available, these curves have typically not considered the target location in the brain, target histology, or treatment plan conformality as parameters in the calculation. In this study, a predictive model was generated to estimate the probability of cranial neuropathies as a result of acoustic schwannoma radiosurgery. Methods and Materials: The dose-volume histogram reduction scheme was used to calculate the normal tissue complication probability (NTCP) from brainstem dose-volume histograms. The model's fitting parameters were optimized to provide the best fit to the observed complication data for acoustic neuroma patients treated with stereotactic radiosurgery at the University of Florida. The calculation was then applied to the remainder of the patients in the database. Results: The best fit to our clinical data was obtained using n = 0.04, m = 0.15, and no. alphano. /no. betano. = 2.1 Gy -1 . Although the fitting parameter m is relatively consistent with ranges found in the literature, both the volume parameter, n, and no. alphano. /no. betano. are much smaller than the values quoted in the literature. The fit to our clinical data indicates that brainstem, or possibly a specific portion of the brainstem, is more radiosensitive than the parameters in the literature indicate, and that there is very little volume effect; in other words, irradiation of a small fraction of the brainstem yields NTCPs that are nearly as high as those calculated for entire volume irradiation. These new fitting parameters are specific to acoustic neuroma radiosurgery, and the small volume effect that we observe may be an artifact of the fixed relationship of acoustic tumors to specific regions of the brainstem. Applying the model to our patient database, we calculate an average NTCP of 7.2% for patients who had no

  10. The estimation of collision probabilities in complicated geometries

    International Nuclear Information System (INIS)

    Roth, M.J.

    1969-04-01

    This paper demonstrates how collision probabilities in complicated geometries may be estimated. It is assumed that the reactor core may be divided into a number of cells each with simple geometry so that a collision probability matrix can be calculated for each cell by standard methods. It is then shown how these may be joined together. (author)

  11. Incidence of late rectal bleeding in high-dose conformal radiotherapy of prostate cancer using equivalent uniform dose-based and dose-volume-based normal tissue complication probability models

    International Nuclear Information System (INIS)

    Soehn, Matthias; Yan Di; Liang Jian; Meldolesi, Elisa; Vargas, Carlos; Alber, Markus

    2007-01-01

    Purpose: Accurate modeling of rectal complications based on dose-volume histogram (DVH) data are necessary to allow safe dose escalation in radiotherapy of prostate cancer. We applied different equivalent uniform dose (EUD)-based and dose-volume-based normal tissue complication probability (NTCP) models to rectal wall DVHs and follow-up data for 319 prostate cancer patients to identify the dosimetric factors most predictive for Grade ≥ 2 rectal bleeding. Methods and Materials: Data for 319 patients treated at the William Beaumont Hospital with three-dimensional conformal radiotherapy (3D-CRT) under an adaptive radiotherapy protocol were used for this study. The following models were considered: (1) Lyman model and (2) logit-formula with DVH reduced to generalized EUD (3) serial reconstruction unit (RU) model (4) Poisson-EUD model, and (5) mean dose- and (6) cutoff dose-logistic regression model. The parameters and their confidence intervals were determined using maximum likelihood estimation. Results: Of the patients, 51 (16.0%) showed Grade 2 or higher bleeding. As assessed qualitatively and quantitatively, the Lyman- and Logit-EUD, serial RU, and Poisson-EUD model fitted the data very well. Rectal wall mean dose did not correlate to Grade 2 or higher bleeding. For the cutoff dose model, the volume receiving > 73.7 Gy showed most significant correlation to bleeding. However, this model fitted the data more poorly than the EUD-based models. Conclusions: Our study clearly confirms a volume effect for late rectal bleeding. This can be described very well by the EUD-like models, of which the serial RU- and Poisson-EUD model can describe the data with only two parameters. Dose-volume-based cutoff-dose models performed worse

  12. Information-theoretic methods for estimating of complicated probability distributions

    CERN Document Server

    Zong, Zhi

    2006-01-01

    Mixing up various disciplines frequently produces something that are profound and far-reaching. Cybernetics is such an often-quoted example. Mix of information theory, statistics and computing technology proves to be very useful, which leads to the recent development of information-theory based methods for estimating complicated probability distributions. Estimating probability distribution of a random variable is the fundamental task for quite some fields besides statistics, such as reliability, probabilistic risk analysis (PSA), machine learning, pattern recognization, image processing, neur

  13. Optimization of radiation therapy, III: a method of assessing complication probabilities from dose-volume histograms

    International Nuclear Information System (INIS)

    Lyman, J.T.; Wolbarst, A.B.

    1987-01-01

    To predict the likelihood of success of a therapeutic strategy, one must be able to assess the effects of the treatment upon both diseased and healthy tissues. This paper proposes a method for determining the probability that a healthy organ that receives a non-uniform distribution of X-irradiation, heat, chemotherapy, or other agent will escape complications. Starting with any given dose distribution, a dose-cumulative-volume histogram for the organ is generated. This is then reduced by an interpolation scheme (involving the volume-weighting of complication probabilities) to a slightly different histogram that corresponds to the same overall likelihood of complications, but which contains one less step. The procedure is repeated, one step at a time, until there remains a final, single-step histogram, for which the complication probability can be determined. The formalism makes use of a complication response function C(D, V) which, for the given treatment schedule, represents the probability of complications arising when the fraction V of the organ receives dose D and the rest of the organ gets none. Although the data required to generate this function are sparse at present, it should be possible to obtain the necessary information from in vivo and clinical studies. Volume effects are taken explicitly into account in two ways: the precise shape of the patient's histogram is employed in the calculation, and the complication response function is a function of the volume

  14. Neutron transport by collision probability method in complicated geometries

    International Nuclear Information System (INIS)

    Constantin, Marin

    2000-01-01

    For the first flight collision probability (FFCP) method a rapidly increasing of the memory requirements and execution time with the number of discrete regions occurs. Generally, the use of the method is restricted at cell/supercell level. However, the amazing developments both in computer hardware and computer architecture allow a real extending of the problems' domain and a more detailed treatment of the geometry. Two ways are discussed into the paper: the direct design of new codes and the improving of the mainframe old versions. The author's experience is focused on the performances' improving of the 3D integral transport code PIJXYZ (from an old version to a modern one) and on the design and developing of the 2D transport code CP 2 D in the last years. In the first case an optimization process have been performed before the parallelization. In the second a modular design and the newest techniques (factorization of the geometry, the macrobands method, the mobile set of chords, the automatic calculation of the integration error, optimal algorithms for the innermost programming level, the mixed method for tracking process and CPs calculation, etc.) were adopted. In both cases the parallelization uses a PCs network system. Some short examples for CP 2 D and PIJXYZ calculation are presented: reactivity void effect in typical CANDU cells using a multistratified coolant model, a problem of some adjacent fuel assemblies, CANDU reactivity devices 3D simulation. (author)

  15. Hard and soft tissue surgical complications in dental implantology.

    Science.gov (United States)

    Aziz, Shahid R

    2015-05-01

    This article discusses surgical complications associated with the placement of dental implants, specifically focusing on how they occur (etiology), as well as their management and prevention. Dental implant surgical complications can be classified into those of hard and soft tissues. In general, complications can be avoided with thorough preoperative treatment planning and proper surgical technique. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Calculation of complication probability of pion treatment at PSI using dose-volume histograms

    International Nuclear Information System (INIS)

    Nakagawa, Keiichi; Akanuma, Atsuo; Aoki, Yukimasa

    1991-01-01

    In the conformation technique a target volume is irradiated uniformly as in conventional radiations, whereas surrounding tissue and organs are nonuniformly irradiated. Clinical data on radiation injuries that accumulate with conventional radiation are not applicable without appropriate compensation. Recently a putative solution of this problem was proposed by Lyman using dose-volume histograms. This histogram reduction method reduces a given dose-volume histogram of an organ to a single step which corresponds to the equivalent complication probability by interpolation. As a result it converts nonuniform radiation into a unique dose to the whole organ which has the equivalent likelihood of radiation injury. This method is based on low LET radiation with conventional fractionation schedules. When it is applied to high LET radiation such as negative pion treatment, a high LET dose should be converted to an equivalent photon dose using an appropriate value of RBE. In the present study the histogram reduction method was applied to actual patients treated by the negative pion conformation technique at the Paul Scherrer Institute. Out of evaluable 90 cases of pelvic tumors, 16 developed grade III-IV bladder injury, and 7 developed grade III-IV rectal injury. The 90 cases were divided into roughly equal groups according to the equivalent doses to the entire bladder and rectum. Complication rates and equivalent doses to the full organs in these groups could be represented by a sigmoid dose-effect relation. When RBE from a pion dose to a photon dose is assumed to be 2.1 for bladder injury, the rates of bladder complications fit best to the theoretical complication curve. When the RBE value was 2.3, the rates of rectal injury fit the theoretical curve best. These values are close to the conversion factor of 2.0 that is used in clinical practice at PSI. This agreement suggests the clinical feasibility of the histogram reduction method in conformation radiotherapy. (author)

  17. Probabilities of Pulmonary and Cardiac Complications and Radiographic Parameters in Breast Cancer Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Noh, O Kyu; Paek, Sung Ho; Ahn, Seung Do; Choi, Eun Kyung; Lee, Sang Wook; Song, Si Yeol; Yoon, Sang Min; Kim, Jong Hoon [Dept. of Radiation Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of)

    2010-11-15

    To evaluate the relationship between the normal tissue complication probability (NTCP) of 3- dimensional (3-D) radiotherapy and the radiographic parameters of 2-dimensional (2-D) radiotherapy such as central lung distance (CLD) and maximal heart distance (MHD). We analyzed 110 patients who were treated with postoperative radiotherapy for breast cancer. A two-field tangential technique, a three-field technique, and the reverse hockey stick method were used. The radiation dose administered to whole breast or the chest wall was 50.4 Gy, whereas a 45 Gy was administered to the supraclavicular field. The NTCPs of the heart and lung were calculated by the modified Lyman model and the relative seriality model. For all patients, the NTCPs of radiation-induced pneumonitis and cardiac mortality were 0.5% and 0.7%, respectively. The NTCP of radiation-induced pneumonitis was higher in patients treated with the reverse hockey stick method than in those treated by other two techniques (0.0%, 0.0%, 3.1%, p<0.001). The NTCP of radiation-induced pneumonitis increased with CLD. The NTCP of cardiac mortality increased with MHD (R2=0.808). We found a close correlation between the NTCP of 3-D radiotherapy and 2-D radiographic parameters. Our results are useful to reanalyze the previous 2-D based clinical reports about breast radiation therapy complications as a viewpoint of NTCP.

  18. Probabilities of Pulmonary and Cardiac Complications and Radiographic Parameters in Breast Cancer Radiotherapy

    International Nuclear Information System (INIS)

    Noh, O Kyu; Paek, Sung Ho; Ahn, Seung Do; Choi, Eun Kyung; Lee, Sang Wook; Song, Si Yeol; Yoon, Sang Min; Kim, Jong Hoon

    2010-01-01

    To evaluate the relationship between the normal tissue complication probability (NTCP) of 3- dimensional (3-D) radiotherapy and the radiographic parameters of 2-dimensional (2-D) radiotherapy such as central lung distance (CLD) and maximal heart distance (MHD). We analyzed 110 patients who were treated with postoperative radiotherapy for breast cancer. A two-field tangential technique, a three-field technique, and the reverse hockey stick method were used. The radiation dose administered to whole breast or the chest wall was 50.4 Gy, whereas a 45 Gy was administered to the supraclavicular field. The NTCPs of the heart and lung were calculated by the modified Lyman model and the relative seriality model. For all patients, the NTCPs of radiation-induced pneumonitis and cardiac mortality were 0.5% and 0.7%, respectively. The NTCP of radiation-induced pneumonitis was higher in patients treated with the reverse hockey stick method than in those treated by other two techniques (0.0%, 0.0%, 3.1%, p<0.001). The NTCP of radiation-induced pneumonitis increased with CLD. The NTCP of cardiac mortality increased with MHD (R2=0.808). We found a close correlation between the NTCP of 3-D radiotherapy and 2-D radiographic parameters. Our results are useful to reanalyze the previous 2-D based clinical reports about breast radiation therapy complications as a viewpoint of NTCP.

  19. Reconstruction of complicated skull base defects utilizing free tissue transfer.

    Science.gov (United States)

    Djalilian, Hamid R; Gapany, Markus; Levine, Samuel C

    2002-11-01

    We managed five patients with large skull base defects complicated by complex infections with microvascular free tissue transfer. The first patient developed an infection, cerebrospinal fluid (CSF) leak, and meningitis after undergoing a translabyrinthine resection of an acoustic neuroma. The second patient had a history of a gunshot wound to the temporal bone, with a large defect and an infected cholesteatoma that caused several episodes of meningitis. The third through the fifth patients had persistent CSF leakage and infection refractory to conventional therapy. In all cases prior attempts of closure with fat grafts or regional flaps had failed. Rectus abdominis myofascial free flap, radial forearm free flap or a gracilis muscle free flap was used after debridement of the infected cavities. The CSF leaks, local infections, and meningitis were controlled within a week. In our experience, microvascular free tissue provides the necessary bulk of viable, well-vascularized tissue, which not only assures a mechanical seal but also helps clear the local infection.

  20. Impact of target point deviations on control and complication probabilities in stereotactic radiosurgery of AVMs and metastases

    International Nuclear Information System (INIS)

    Treuer, Harald; Kocher, Martin; Hoevels, Moritz; Hunsche, Stefan; Luyken, Klaus; Maarouf, Mohammad; Voges, Juergen; Mueller, Rolf-Peter; Sturm, Volker

    2006-01-01

    Objective: Determination of the impact of inaccuracies in the determination and setup of the target point in stereotactic radiosurgery (SRS) on the expectable complication and control probabilities. Methods: Two randomized samples of patients with arteriovenous malformation (AVM) (n = 20) and with brain metastases (n = 20) treated with SRS were formed, and the probability for complete obliteration (COP) or complete remission (CRP), the size of the 10 Gy-volume in the brain tissue (VOI10), and the probability for radiation necrosis (NTCP) were calculated. The dose-effect relations for COP and CRP were fitted to clinical data. Target point deviations were simulated through random vectors and the resulting probabilities and volumes were calculated and compared with the values of the treatment plan. Results: The decrease of the relative value of the control probabilities at 1 mm target point deviation was up to 4% for AVMs and up to 10% for metastases. At 2 mm the median decrease was 5% for AVMs and 9% for metastases. The value for the target point deviation, at which COP and CRP decreased about 0.05 in 90% of the cases, was 1.3 mm. The increase of NTCP was maximally 0.0025 per mm target point deviation for AVMs and 0.0035/mm for metastases. The maximal increase of VOI10 was 0.7 cm 3 /mm target point deviation in both patient groups. Conclusions: The upper limit for tolerable target point deviations is at 1.3 mm. If this value cannot be achieved during the system test, a supplementary safety margin should be applied for the definition of the target volume. A better accuracy level is desirable, in order to ensure optimal chances for the success of the treatment. The target point precision is less important for the minimization of the probability of radiation necroses

  1. Unexpected complication associated with balneotherapy: Skin and soft tissue infection

    Science.gov (United States)

    Alım, Bülent; Bostancı, Fahrettin; Servi, M. Alperen; Ćetinel, Sinan; Bingöl, M. Ozan

    2017-04-01

    Balneotherapy cure is an ongoing process, but patients can benefit most when cure is complete. For these reason, patients should be closely monitored and necessary precautions should be taken in terms of the complications that may occur in order to prevent the interruption or discontinuation of balneotherapy. Here, we wanted to represent a case that developed left leg soft tissue infection during the application of balneotherapy and because of this reason we stopped the balneotherapy As a result, when balneotherapy is planned for patients with risk factors such as diabetes and obesity, frequent examination of the skin and the application of skin moisturizers will be beneficial to prevent itching and skin dryness.

  2. Reconstruction of soft tissue after complicated calcaneal fractures.

    Science.gov (United States)

    Koski, E Antti; Kuokkanen, Hannu O M; Koskinen, Seppo K; Tukiainen, Erkki J

    2004-01-01

    A total of 35 flap reconstructions were done to cover exposed calcaneal bones in 31 patients. All patients had calcaneal fractures, 19 of which were primarily open. Soft tissue reconstruction for the closed fractures was indicated by a postoperative wound complication. A microvascular flap was used for reconstruction in 21 operations (gracilis, n = 11; anterolateral thigh, n = 5; rectus abdominis, n = 3; and latissimus dorsi, n = 2). A suralis neurocutaneous flap was used in eight, local muscle flaps in three, and local skin flaps in three cases. The mean follow-up time was 14 months (range 3 months-4 years). One suralis flap failed and was replaced by a latissimus dorsi flap. Necrosis of the edges that required revision affected three flaps. Deep infection developed in two patients and delayed wound healing in another four. During the follow-up the soft tissues healed in all patients and there were no signs of calcaneal osteitis. Flaps were considered too bulky in five patients. Soft tissues heal most rapidly with microvascular flaps. In the long term, gracilis muscle covered with free skin grafts gives a good contour to the foot. The suralis flap is reliable and gives a good final aesthetic outcome. Local muscles can be transposed for reconstruction in small defects.

  3. Probability of cavitation for single ultrasound pulses applied to tissues and tissue-mimicking materials.

    Science.gov (United States)

    Maxwell, Adam D; Cain, Charles A; Hall, Timothy L; Fowlkes, J Brian; Xu, Zhen

    2013-03-01

    In this study, the negative pressure values at which inertial cavitation consistently occurs in response to a single, two-cycle, focused ultrasound pulse were measured in several media relevant to cavitation-based ultrasound therapy. The pulse was focused into a chamber containing one of the media, which included liquids, tissue-mimicking materials, and ex vivo canine tissue. Focal waveforms were measured by two separate techniques using a fiber-optic hydrophone. Inertial cavitation was identified by high-speed photography in optically transparent media and an acoustic passive cavitation detector. The probability of cavitation (P(cav)) for a single pulse as a function of peak negative pressure (p(-)) followed a sigmoid curve, with the probability approaching one when the pressure amplitude was sufficient. The statistical threshold (defined as P(cav) = 0.5) was between p(-) = 26 and 30 MPa in all samples with high water content but varied between p(-) = 13.7 and >36 MPa in other media. A model for radial cavitation bubble dynamics was employed to evaluate the behavior of cavitation nuclei at these pressure levels. A single bubble nucleus with an inertial cavitation threshold of p(-) = 28.2 megapascals was estimated to have a 2.5 nm radius in distilled water. These data may be valuable for cavitation-based ultrasound therapy to predict the likelihood of cavitation at various pressure levels and dimensions of cavitation-induced lesions in tissue. Copyright © 2013 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  4. Joint probability discrimination between stationary tissue and blood velocity signals

    DEFF Research Database (Denmark)

    Schlaikjer, Malene; Jensen, Jørgen Arendt

    2001-01-01

    before and after echo-canceling, and (b) the amplitude variations between samples in consecutive RF-signals before and after echo-canceling. The statistical discriminator was obtained by computing the probability density functions (PDFs) for each feature through histogram analysis of data....... This study presents a new statistical discriminator. Investigation of the RF-signals reveals that features can be derived that distinguish the segments of the signal, which do an do not carry information on the blood flow. In this study 4 features, have been determined: (a) the energy content in the segments....... The discrimination is performed by determining the joint probability of the features for the segment under investigation and choosing the segment type that is most likely. The method was tested on simulated data resembling RF-signals from the carotid artery....

  5. Probability

    CERN Document Server

    Shiryaev, A N

    1996-01-01

    This book contains a systematic treatment of probability from the ground up, starting with intuitive ideas and gradually developing more sophisticated subjects, such as random walks, martingales, Markov chains, ergodic theory, weak convergence of probability measures, stationary stochastic processes, and the Kalman-Bucy filter Many examples are discussed in detail, and there are a large number of exercises The book is accessible to advanced undergraduates and can be used as a text for self-study This new edition contains substantial revisions and updated references The reader will find a deeper study of topics such as the distance between probability measures, metrization of weak convergence, and contiguity of probability measures Proofs for a number of some important results which were merely stated in the first edition have been added The author included new material on the probability of large deviations, and on the central limit theorem for sums of dependent random variables

  6. Avoiding Complications in Bone and Soft Tissue Ablation

    International Nuclear Information System (INIS)

    Kurup, A. Nicholas; Schmit, Grant D.; Morris, Jonathan M.; Atwell, Thomas D.; Schmitz, John J.; Weisbrod, Adam J.; Woodrum, David A.; Eiken, Patrick W.; Callstrom, Matthew R.

    2017-01-01

    As with percutaneous ablation of tumors in the liver, lungs, and kidneys, ablation of bone and non-visceral soft tissue tumors carries risk, primarily from collateral damage to vital structures in proximity to the target tumor. Certain risks are of particular interest when ablating bone and non-visceral soft tissue tumors, namely neural or skin injury, bowel injury, fracture, and gas embolism from damaged applicators. Ablation of large volume tumors also carries special risk. Many techniques may be employed by the interventional radiologist to minimize complications when treating tumors in the musculoskeletal system. These methods include those to depict, displace, or monitor critical structures. Thus, measures to provide thermoprotection may be active, such as careful ablation applicator placement and use of various displacement techniques, as well as passive, including employment of direct temperature, radiographic, or neurophysiologic monitoring techniques. Cementoplasty should be considered in certain skeletal locations at risk of fracture. Patients treated with large volume tumors should be monitored for renal dysfunction and properly hydrated. Finally, ablation applicators should be cautiously placed in the constrained environment of intact bone.

  7. Avoiding Complications in Bone and Soft Tissue Ablation

    Energy Technology Data Exchange (ETDEWEB)

    Kurup, A. Nicholas, E-mail: kurup.anil@mayo.edu; Schmit, Grant D., E-mail: schmit.grant@mayo.edu; Morris, Jonathan M., E-mail: morris.jonathan@mayo.edu; Atwell, Thomas D., E-mail: atwell.thomas@mayo.edu; Schmitz, John J., E-mail: schmitz.john@mayo.edu; Weisbrod, Adam J., E-mail: weisbrod.adam@mayo.edu; Woodrum, David A., E-mail: woodrum.david@mayo.edu; Eiken, Patrick W., E-mail: eiken.patrick@mayo.edu; Callstrom, Matthew R., E-mail: callstrom.matthew@mayo.edu [Mayo Clinic, Department of Radiology (United States)

    2017-02-15

    As with percutaneous ablation of tumors in the liver, lungs, and kidneys, ablation of bone and non-visceral soft tissue tumors carries risk, primarily from collateral damage to vital structures in proximity to the target tumor. Certain risks are of particular interest when ablating bone and non-visceral soft tissue tumors, namely neural or skin injury, bowel injury, fracture, and gas embolism from damaged applicators. Ablation of large volume tumors also carries special risk. Many techniques may be employed by the interventional radiologist to minimize complications when treating tumors in the musculoskeletal system. These methods include those to depict, displace, or monitor critical structures. Thus, measures to provide thermoprotection may be active, such as careful ablation applicator placement and use of various displacement techniques, as well as passive, including employment of direct temperature, radiographic, or neurophysiologic monitoring techniques. Cementoplasty should be considered in certain skeletal locations at risk of fracture. Patients treated with large volume tumors should be monitored for renal dysfunction and properly hydrated. Finally, ablation applicators should be cautiously placed in the constrained environment of intact bone.

  8. Calculation of the uncertainty in complication probability for various dose-response models, applied to the parotid gland

    International Nuclear Information System (INIS)

    Schilstra, C.; Meertens, H.

    2001-01-01

    Purpose: Usually, models that predict normal tissue complication probability (NTCP) are fitted to clinical data with the maximum likelihood (ML) method. This method inevitably causes a loss of information contained in the data. In this study, an alternative method is investigated that calculates the parameter probability distribution (PD), and, thus, conserves all information. The PD method also allows the calculation of the uncertainty in the NTCP, which is an (often-neglected) prerequisite for the intercomparison of both treatment plans and NTCP models. The PD and ML methods are applied to parotid gland data, and the results are compared. Methods and Materials: The drop in salivary flow due to radiotherapy was measured in 25 parotid glands of 15 patients. Together with the parotid gland dose-volume histograms (DVH), this enabled the calculation of the parameter PDs for three different NTCP models (Lyman, relative seriality, and critical volume). From these PDs, the NTCP and its uncertainty could be calculated for arbitrary parotid gland DVHs. ML parameters and resulting NTCP values were calculated also. Results: All models fitted equally well. The parameter PDs turned out to have nonnormal shapes and long tails. The NTCP predictions of the ML and PD method usually differed considerably, depending on the NTCP model and the nature of irradiation. NTCP curves and ML parameters suggested a highly parallel organization of the parotid gland. Conclusions: Considering the substantial differences between the NTCP predictions of the ML and PD method, the use of the PD method is preferred, because this is the only method that takes all information contained in the clinical data into account. Furthermore, PD method gives a true measure of the uncertainty in the NTCP

  9. Treatment of Soft Tissue Filler Complications: Expert Consensus Recommendations.

    Science.gov (United States)

    Urdiales-Gálvez, Fernando; Delgado, Nuria Escoda; Figueiredo, Vitor; Lajo-Plaza, José V; Mira, Mar; Moreno, Antonio; Ortíz-Martí, Francisco; Del Rio-Reyes, Rosa; Romero-Álvarez, Nazaret; Del Cueto, Sofía Ruiz; Segurado, María A; Rebenaque, Cristina Villanueva

    2018-04-01

    Dermal fillers have been increasingly used in minimally invasive facial esthetic procedures. This widespread use has led to a rise in reports of associated complications. The aim of this expert consensus report is to describe potential adverse events associated with dermal fillers and to provide guidance on their treatment and avoidance. A multidisciplinary group of experts in esthetic treatments convened to discuss the management of the complications associated with dermal fillers use. A search was performed for English, French, and Spanish language articles in MEDLINE, the Cochrane Database, and Google Scholar using the search terms "complications" OR "soft filler complications" OR "injectable complications" AND "dermal fillers" AND "Therapy". An initial document was drafted by the Coordinating Committee, and it was reviewed and modified by the experts, until a final text was agreed upon and validated. The panel addressed consensus recommendations about the classification of filler complications according to the time of onset and about the clinical management of different complications including bruising, swelling, edema, infections, lumps and bumps, skin discoloration, and biofilm formation. Special attention was paid to vascular compromise and retinal artery occlusion. Clinicians should be fully aware of the signs and symptoms related to complications and be prepared to confidently treat them. Establishing action protocols for emergencies, with agents readily available in the office, would reduce the severity of adverse outcomes associated with injection of hyaluronic acid fillers in the cosmetic setting. This document seeks to lay down a set of recommendations and to identify key issues that may be useful for clinicians who are starting to use dermal fillers. Additionally, this document provides a better understanding about the diagnoses and management of complications if they do occur. This journal requires that authors assign a level of evidence to each

  10. A probable risk factor of female breast cancer: study on benign and malignant breast tissue samples.

    Science.gov (United States)

    Rehman, Sohaila; Husnain, Syed M

    2014-01-01

    The study reports enhanced Fe, Cu, and Zn contents in breast tissues, a probable risk factor of breast cancer in females. Forty-one formalin-fixed breast tissues were analyzed using atomic absorption spectrophotometry. Twenty malignant, six adjacent to malignant and 15 benign tissues samples were investigated. The malignant tissues samples were of grade 11 and type invasive ductal carcinoma. The quantitative comparison between the elemental levels measured in the two types of specimen (benign and malignant) tissues (removed after surgery) suggests significant elevation of these metals (Fe, Cu, and Zn) in the malignant tissue. The specimens were collected just after mastectomy of women aged 19 to 59 years from the hospitals of Islamabad and Rawalpindi, Pakistan. Most of the patients belong to urban areas of Pakistan. Findings of study depict that these elements have a promising role in the initiation and development of carcinoma as consistent pattern of elevation for Fe, Cu, and Zn was observed. The results showed the excessive accumulation of Fe (229 ± 121 mg/L) in malignant breast tissue samples of patients (p factor of breast cancer. In order to validate our method of analysis, certified reference material muscle tissue lyophilized (IAEA) MA-M-2/TM was analyzed for metal studied. Determined concentrations were quite in good agreement with certified levels. Asymmetric concentration distribution for Fe, Cu, and Zn was observed in both malignant and benign tissue samples.

  11. The effect of customized beam shaping on normal tissue complications in radiation therapy of parotid gland tumors

    International Nuclear Information System (INIS)

    Keus, R.; Boer, R. de; Lebesque, J.; Noach, P.

    1991-01-01

    The impact of customized beam shaping was studied for 5 patients with parotid tumors treated with a paired wedged field technique. For each patient 2 plans were generated. The standard plan had unblocked portals with field sizes defined by the largest target contour found in any CT slice. In the 2nd plan customized beam's view (BEV) designed blocks were added to both beams. The differences in those distributions between the 2 types of plans were evaluated using dose-volume histograms (DVH). As expected, the dose distribution within the target volume showed no difference. However, a considerable sparing of normal tissue was observed for the plans with customized blocks. The volume of un-necessary exposed normal tissue that received more than 90 percent of the prescribed dose, was reduced by a factor of about 4: from 165 to 44 percent on an average, if the volume is expressed as a percentage of the target volume in each patient. In particular, the homolateral mandible showed a mean decrease of 21 percent of integral dose when blocks were used. Normal tissue complication probabilities (NTCP) were calculated. For a tumor dose of 70 Gy, the average bone necrosis probability was reduced from 8.4 percent (no blocks) to 4.1. percent (blocks). For other normal tissues such as nervous tissue, other soft tissues and bones a substantial reduction of integral dose was found for al patients when individual blocks were used. (author). 10 refs.; 4 figs.; 2 tabs

  12. Chemo-IMRT of Oropharyngeal Cancer Aiming to Reduce Dysphagia: Swallowing Organs Late Complication Probabilities and Dosimetric Correlates

    International Nuclear Information System (INIS)

    Eisbruch, Avraham; Kim, Hyungjin M.; Feng, Felix Y.; Lyden, Teresa H.; Haxer, Marc J.; Feng, Mary; Worden, Frank P.; Bradford, Carol R.; Prince, Mark E.; Moyer, Jeffrey S.; Wolf, Gregory T.; Chepeha, Douglas B.; Ten Haken, Randall K.

    2011-01-01

    Purpose: Assess dosimetric correlates of long-term dysphagia after chemo-intensity-modulated radiotherapy (IMRT) of oropharyngeal cancer (OPC) sparing parts of the swallowing organs. Patients and Methods: Prospective longitudinal study: weekly chemotherapy concurrent with IMRT for Stages III/IV OPC, aiming to reduce dysphagia by sparing noninvolved parts of swallowing-related organs: pharyngeal constrictors (PC), glottic and supraglottic larynx (GSL), and esophagus, as well as oral cavity and major salivary glands. Dysphagia outcomes included patient-reported Swallowing and Eating Domain scores, Observer-based (CTCAEv.2) dysphagia, and videofluoroscopy (VF), before and periodically after therapy through 2 years. Relationships between dosimetric factors and worsening (from baseline) of dysphagia through 2 years were assessed by linear mixed-effects model. Results: Seventy-three patients participated. Observer-based dysphagia was not modeled because at >6 months there were only four Grade ≥2 cases (one of whom was feeding-tube dependent). PC, GSL, and esophagus mean doses, as well as their partial volume doses (V D s), were each significantly correlated with all dysphagia outcomes. However, the V D s for each organ intercorrelated and also highly correlated with the mean doses, leaving only mean doses significant. Mean doses to each of the parts of the PCs (superior, middle, and inferior) were also significantly correlated with all dysphagia measures, with superior PCs demonstrating highest correlations. For VF-based strictures, most significant predictor was esophageal mean doses (48±17 Gy in patients with, vs 27±12 in patients without strictures, p = 0.004). Normal tissue complication probabilities (NTCPs) increased moderately with mean doses without any threshold. For increased VF-based aspirations or worsened VF summary scores, toxic doses (TDs) 50 and TD 25 were 63 Gy and 56 Gy for PC, and 56 Gy and 39 Gy for GSL, respectively. For both PC and GSL, patient

  13. Wound Complications in Preoperatively Irradiated Soft-Tissue Sarcomas of the Extremities

    International Nuclear Information System (INIS)

    Rosenberg, Lewis A.; Esther, Robert J.; Erfanian, Kamil; Green, Rebecca; Kim, Hong Jin; Sweeting, Raeshell; Tepper, Joel E.

    2013-01-01

    Purpose: To determine whether the involvement of plastic surgery and the use of vascularized tissue flaps reduces the frequency of major wound complications after radiation therapy for soft-tissue sarcomas (STS) of the extremities. Methods and Materials: This retrospective study evaluated patients with STS of the extremities who underwent radiation therapy before surgery. Major complications were defined as secondary operations with anesthesia, seroma/hematoma aspirations, readmission for wound complications, or persistent deep packing. Results: Between 1996 and 2010, 73 patients with extremity STS were preoperatively irradiated. Major wound complications occurred in 32% and secondary operations in 16% of patients. Plastic surgery closed 63% of the wounds, and vascularized tissue flaps were used in 22% of closures. When plastic surgery performed closure the frequency of secondary operations trended lower (11% vs 26%; P=.093), but the frequency of major wound complications was not different (28% vs 38%; P=.43). The use of a vascularized tissue flap seemed to have no effect on the frequency of complications. The occurrence of a major wound complication did not affect disease recurrence or survival. For all patients, 3-year local control was 94%, and overall survival was 72%. Conclusions: The rates of wound complications and secondary operations in this study were very similar to previously published results. We were not able to demonstrate a significant relationship between the involvement of plastic surgery and the rate of wound complications, although there was a trend toward reduced secondary operations when plastic surgery was involved in the initial operation. Wound complications were manageable and did not compromise outcomes.

  14. Wound Complications in Preoperatively Irradiated Soft-Tissue Sarcomas of the Extremities

    Energy Technology Data Exchange (ETDEWEB)

    Rosenberg, Lewis A. [Department of Radiation Oncology, University of North Carolina, Chapel Hill, North Carolina (United States); Esther, Robert J. [Department of Orthopedics, University of North Carolina, Chapel Hill, North Carolina (United States); Erfanian, Kamil [Department of Surgery, University of North Carolina, Chapel Hill, North Carolina (United States); Green, Rebecca [Department of Radiation Oncology, University of North Carolina, Chapel Hill, North Carolina (United States); Kim, Hong Jin; Sweeting, Raeshell [Department of Surgery, University of North Carolina, Chapel Hill, North Carolina (United States); Tepper, Joel E., E-mail: tepper@med.unc.edu [Department of Radiation Oncology, University of North Carolina, Chapel Hill, North Carolina (United States)

    2013-02-01

    Purpose: To determine whether the involvement of plastic surgery and the use of vascularized tissue flaps reduces the frequency of major wound complications after radiation therapy for soft-tissue sarcomas (STS) of the extremities. Methods and Materials: This retrospective study evaluated patients with STS of the extremities who underwent radiation therapy before surgery. Major complications were defined as secondary operations with anesthesia, seroma/hematoma aspirations, readmission for wound complications, or persistent deep packing. Results: Between 1996 and 2010, 73 patients with extremity STS were preoperatively irradiated. Major wound complications occurred in 32% and secondary operations in 16% of patients. Plastic surgery closed 63% of the wounds, and vascularized tissue flaps were used in 22% of closures. When plastic surgery performed closure the frequency of secondary operations trended lower (11% vs 26%; P=.093), but the frequency of major wound complications was not different (28% vs 38%; P=.43). The use of a vascularized tissue flap seemed to have no effect on the frequency of complications. The occurrence of a major wound complication did not affect disease recurrence or survival. For all patients, 3-year local control was 94%, and overall survival was 72%. Conclusions: The rates of wound complications and secondary operations in this study were very similar to previously published results. We were not able to demonstrate a significant relationship between the involvement of plastic surgery and the rate of wound complications, although there was a trend toward reduced secondary operations when plastic surgery was involved in the initial operation. Wound complications were manageable and did not compromise outcomes.

  15. The average baboon brain: MRI templates and tissue probability maps from 89 individuals.

    Science.gov (United States)

    Love, Scott A; Marie, Damien; Roth, Muriel; Lacoste, Romain; Nazarian, Bruno; Bertello, Alice; Coulon, Olivier; Anton, Jean-Luc; Meguerditchian, Adrien

    2016-05-15

    The baboon (Papio) brain is a remarkable model for investigating the brain. The current work aimed at creating a population-average baboon (Papio anubis) brain template and its left/right hemisphere symmetric version from a large sample of T1-weighted magnetic resonance images collected from 89 individuals. Averaging the prior probability maps output during the segmentation of each individual also produced the first baboon brain tissue probability maps for gray matter, white matter and cerebrospinal fluid. The templates and the tissue probability maps were created using state-of-the-art, freely available software tools and are being made freely and publicly available: http://www.nitrc.org/projects/haiko89/ or http://lpc.univ-amu.fr/spip.php?article589. It is hoped that these images will aid neuroimaging research of the baboon by, for example, providing a modern, high quality normalization target and accompanying standardized coordinate system as well as probabilistic priors that can be used during tissue segmentation. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Risk Factors for Complications Differ Between Stages of Tissue-Expander Breast Reconstruction.

    Science.gov (United States)

    Lovecchio, Francis; Jordan, Sumanas W; Lim, Seokchun; Fine, Neil A; Kim, John Y S

    2015-09-01

    Tissue-expander (TE) placement followed by implant exchange is currently the most popular method of breast reconstruction. There is a relative paucity of data demonstrating patient factors that predict complications specifically by stage of surgery. The present study attempts to determine what complications are most likely to occur at each stage and how the risk factors for complications vary by stage of reconstruction. A retrospective chart review was performed on all 1275 patients who had TEs placed by the 2 senior authors between 2004 and 2013. Complication rates were determined at each stage of reconstruction, and these rates were further compared between patients who had pre-stage I radiation, post-stage I radiation, and no radiation exposure. Multivariate logistic regression was used to identify independent predictors of complications at each stage of reconstruction. A total of 1639 consecutive TEs were placed by the senior authors during the study period. The overall rate for experiencing a complication at any stage of surgery was 17%. Complications occurred at uniformly higher rates during stage I for all complications (92% stage I vs 7% stage II vs 1% stage III, P higher intraoperative percent fill (OR, 3.3; 95% CI, 1.7-6.3). Post-stage I radiation was the only independent risk factor for a stage II complication (OR, 4.5; 95% CI, 1.4-15.2). Complications occur at higher rates after stage I than after stage II, and as expected, stage III complications are exceedingly rare. Risk factors for stage I complications are different from risk factors for stage II complications. Body mass index and smoking are associated with complications at stage I, but do not predict complications at stage II surgery. The stratification of risk factors by stage of surgery will help surgeons and patients better manage both risk and expectations.

  17. Radiation risk of tissue late effects, a net consequence of probabilities of various cellular responses

    International Nuclear Information System (INIS)

    Feinendegen, L.E.

    1991-01-01

    Late effects from the exposure to low doses of ionizing radiation are hardly or not at all observed in man mainly due to the low values of risk coefficients that preclude statistical analyses of data from populations that are exposed to doses less than 0.2 Gy. In order to arrive at an assessment of potential risk from radiation exposure in the low dose range, the microdosimetry approach is essential. In the low dose range, ionizing radiation generates particle tracks, mainly electrons, which are distributed rather heterogeneously within the exposed tissue. Taking the individual cell as the elemental unit of life, observations and calculations of cellular responses to being hit by energy depositions events from low LET type are analysed. It emerges that besides the probability of a hit cell to sustain a detrimental effect with the consequense of malignant transformation there are probabilities of various adaptive responses that equipp the hit cell with a benefit. On the one hand, an improvement of cellular radical detoxification was observed in mouse bone marrow cells; another adaptive response pertaining to improved DNA repair, was reported for human lymphocytes. The improved radical detoxification in mouse bone marrow cells lasts for a period of 5-10 hours and improved DNA repair in human lymphocytes was seen for some 60 hours following acute irradiation. It is speculated that improved radical detoxification and improved DNA repair may reduce the probability of spontaneous carcinogenesis. Thus it is proposed to weigh the probability of detriment for a hit cell within a multicellular system against the probability of benefit through adaptive responses in other hit cells in the same system per radiation exposure. In doing this, the net effect of low doses of low LET radiation in tissue with individual cells being hit by energy deposition events could be zero or even beneficial. (orig./MG)

  18. Quantifying Unnecessary Normal Tissue Complication Risks due to Suboptimal Planning: A Secondary Study of RTOG 0126

    International Nuclear Information System (INIS)

    Moore, Kevin L.; Schmidt, Rachel; Moiseenko, Vitali; Olsen, Lindsey A.; Tan, Jun; Xiao, Ying; Galvin, James; Pugh, Stephanie; Seider, Michael J.; Dicker, Adam P.; Bosch, Walter; Michalski, Jeff; Mutic, Sasa

    2015-01-01

    Purpose: The purpose of this study was to quantify the frequency and clinical severity of quality deficiencies in intensity modulated radiation therapy (IMRT) planning in the Radiation Therapy Oncology Group 0126 protocol. Methods and Materials: A total of 219 IMRT patients from the high-dose arm (79.2 Gy) of RTOG 0126 were analyzed. To quantify plan quality, we used established knowledge-based methods for patient-specific dose-volume histogram (DVH) prediction of organs at risk and a Lyman-Kutcher-Burman (LKB) model for grade ≥2 rectal complications to convert DVHs into normal tissue complication probabilities (NTCPs). The LKB model was validated by fitting dose-response parameters relative to observed toxicities. The 90th percentile (22 of 219) of plans with the lowest excess risk (difference between clinical and model-predicted NTCP) were used to create a model for the presumed best practices in the protocol (pDVH 0126,top10% ). Applying the resultant model to the entire sample enabled comparisons between DVHs that patients could have received to DVHs they actually received. Excess risk quantified the clinical impact of suboptimal planning. Accuracy of pDVH predictions was validated by replanning 30 of 219 patients (13.7%), including equal numbers of presumed “high-quality,” “low-quality,” and randomly sampled plans. NTCP-predicted toxicities were compared to adverse events on protocol. Results: Existing models showed that bladder-sparing variations were less prevalent than rectum quality variations and that increased rectal sparing was not correlated with target metrics (dose received by 98% and 2% of the PTV, respectively). Observed toxicities were consistent with current LKB parameters. Converting DVH and pDVH 0126,top10% to rectal NTCPs, we observed 94 of 219 patients (42.9%) with ≥5% excess risk, 20 of 219 patients (9.1%) with ≥10% excess risk, and 2 of 219 patients (0.9%) with ≥15% excess risk. Replanning demonstrated the predicted NTCP

  19. Quantifying Unnecessary Normal Tissue Complication Risks due to Suboptimal Planning: A Secondary Study of RTOG 0126.

    Science.gov (United States)

    Moore, Kevin L; Schmidt, Rachel; Moiseenko, Vitali; Olsen, Lindsey A; Tan, Jun; Xiao, Ying; Galvin, James; Pugh, Stephanie; Seider, Michael J; Dicker, Adam P; Bosch, Walter; Michalski, Jeff; Mutic, Sasa

    2015-06-01

    The purpose of this study was to quantify the frequency and clinical severity of quality deficiencies in intensity modulated radiation therapy (IMRT) planning in the Radiation Therapy Oncology Group 0126 protocol. A total of 219 IMRT patients from the high-dose arm (79.2 Gy) of RTOG 0126 were analyzed. To quantify plan quality, we used established knowledge-based methods for patient-specific dose-volume histogram (DVH) prediction of organs at risk and a Lyman-Kutcher-Burman (LKB) model for grade ≥2 rectal complications to convert DVHs into normal tissue complication probabilities (NTCPs). The LKB model was validated by fitting dose-response parameters relative to observed toxicities. The 90th percentile (22 of 219) of plans with the lowest excess risk (difference between clinical and model-predicted NTCP) were used to create a model for the presumed best practices in the protocol (pDVH0126,top10%). Applying the resultant model to the entire sample enabled comparisons between DVHs that patients could have received to DVHs they actually received. Excess risk quantified the clinical impact of suboptimal planning. Accuracy of pDVH predictions was validated by replanning 30 of 219 patients (13.7%), including equal numbers of presumed "high-quality," "low-quality," and randomly sampled plans. NTCP-predicted toxicities were compared to adverse events on protocol. Existing models showed that bladder-sparing variations were less prevalent than rectum quality variations and that increased rectal sparing was not correlated with target metrics (dose received by 98% and 2% of the PTV, respectively). Observed toxicities were consistent with current LKB parameters. Converting DVH and pDVH0126,top10% to rectal NTCPs, we observed 94 of 219 patients (42.9%) with ≥5% excess risk, 20 of 219 patients (9.1%) with ≥10% excess risk, and 2 of 219 patients (0.9%) with ≥15% excess risk. Replanning demonstrated the predicted NTCP reductions while maintaining the volume of the PTV

  20. Method for Automatic Selection of Parameters in Normal Tissue Complication Probability Modeling

    DEFF Research Database (Denmark)

    Christophides, Damianos; Appelt, Ane L; Gusnanto, Arief

    2018-01-01

    by multicollinearity reduction using the variance inflation factor and genetic algorithm optimization to determine an ordinal logistic regression model that minimizes the Bayesian information criterion. The process was repeated 100 times, and the model with the minimum Bayesian information criterion was recorded...

  1. Iatrogenic Pneumothorax as a Complication to Delayed Breast Reconstruction With Tissue Expander—A Case Report

    DEFF Research Database (Denmark)

    Willert, Cecilie Balslev; Bredgaard, Rikke

    2017-01-01

    Breast reconstruction with expander implant is the most common breast reconstructive procedure. Irradiated patients are seldom reconstructed this way because the tissue expansion is difficult and the complication rates are higher. Pneumothorax is a serious condition and can be seen as a complicat......Breast reconstruction with expander implant is the most common breast reconstructive procedure. Irradiated patients are seldom reconstructed this way because the tissue expansion is difficult and the complication rates are higher. Pneumothorax is a serious condition and can be seen...... as a complication to the operation. Literature is sparse; hence, the only study is by Schneider et al who found an incidence of 0.55%. The study focused on immediate reconstruction only and did not report the percentage of irradiated patients. We present a unique case of iatrogenic pneumothorax in a previously...

  2. Does Acellular Dermal Matrix Thickness Affect Complication Rate in Tissue Expander Based Breast Reconstruction?

    Directory of Open Access Journals (Sweden)

    Jessica F. Rose

    2016-01-01

    Full Text Available Background. While the benefits of using acellular dermal matrices (ADMs in breast reconstruction are well described, their use has been associated with additional complications. The purpose of this study was to determine if ADM thickness affects complications in breast reconstruction. Methods. A retrospective chart review was performed including all tissue expander based breast reconstructions with AlloDerm (LifeCell, Branchburg, NJ over 4 years. We evaluated preoperative characteristics and assessed postoperative complications including seroma, hematoma, infection, skin necrosis, and need for reintervention. We reviewed ADM thickness and time to Jackson-Pratt (JP drain removal. Results. Fifty-five patients underwent 77 ADM-associated tissue expander based breast reconstructions, with average age of 48.1 years and average BMI of 25.9. Average ADM thickness was 1.21 mm. We found higher complication rates in the thick ADM group. Significant associations were found between smokers and skin necrosis (p<0.0001 and seroma and prolonged JP drainage (p=0.0004; radiated reconstructed breasts were more likely to suffer infections (p=0.0085, and elevated BMI is a significant predictor for increased infection rate (p=0.0037. Conclusion. We found a trend toward increased complication rates with thicker ADMs. In the future, larger prospective studies evaluating thickness may provide more information.

  3. Characteristics and intraoperative treatments associated with head and neck free tissue transfer complications and failures.

    Science.gov (United States)

    Hand, William R; McSwain, Julie R; McEvoy, Matthew D; Wolf, Bethany; Algendy, Abdalrahman A; Parks, Matthew D; Murray, John L; Reeves, Scott T

    2015-03-01

    To investigate the association between perioperative patient characteristics and treatment modalities (eg, vasopressor use and volume of fluid administration) with complications and failure rates in patients undergoing head and neck free tissue transfer (FTT). A retrospective review of medical records. Perioperative hospitalization for head and neck FTT at 1 tertiary care medical center between January 1, 2009, and October 31, 2011. Consecutive patients (N=235) who underwent head and neck FTT. Demographic, patient characteristic, and intraoperative data were extracted from medical records. Complication and failure rates within the first 30 days were collected In a multivariate analysis controlling for age, sex, ethnicity, reason for receiving flap, and type and volume of fluid given, perioperative complication was significantly associated with surgical blood loss (P=.019; 95% confidence interval [CI], 1.01-1.16), while the rate of intraoperative fluid administration did not reach statistical significance (P=.06; 95% CI, 0.99-1.28). In a univariate analysis, FTT failure was significantly associated with reason for surgery (odds ratio, 5.40; P=.03; 95% CI, 1.69-17.3) and preoperative diagnosis of coronary artery disease (odds ratio, 3.60; P=.03; 95% CI, 1.16-11.2). Intraoperative vasopressor administration was not associated with either FTT complication or failure rate. FTT complications were associated with surgical blood loss but not the use of vasoactive drugs. For patients undergoing FTT, judicious monitoring of blood loss may help stratify the risk of complication and failure. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2014.

  4. Adipose tissue mitochondrial dysfunction triggers a lipodystrophic syndrome with insulin resistance, hepatosteatosis, and cardiovascular complications.

    Science.gov (United States)

    Vernochet, Cecile; Damilano, Federico; Mourier, Arnaud; Bezy, Olivier; Mori, Marcelo A; Smyth, Graham; Rosenzweig, Anthony; Larsson, Nils-Göran; Kahn, C Ronald

    2014-10-01

    Mitochondrial dysfunction in adipose tissue occurs in obesity, type 2 diabetes, and some forms of lipodystrophy, but whether this dysfunction contributes to or is the result of these disorders is unknown. To investigate the physiological consequences of severe mitochondrial impairment in adipose tissue, we generated mice deficient in mitochondrial transcription factor A (TFAM) in adipocytes by using mice carrying adiponectin-Cre and TFAM floxed alleles. These adiponectin TFAM-knockout (adipo-TFAM-KO) mice had a 75-81% reduction in TFAM in the subcutaneous and intra-abdominal white adipose tissue (WAT) and interscapular brown adipose tissue (BAT), causing decreased expression and enzymatic activity of proteins in complexes I, III, and IV of the electron transport chain (ETC). This mitochondrial dysfunction led to adipocyte death and inflammation in WAT and a whitening of BAT. As a result, adipo-TFAM-KO mice were resistant to weight gain, but exhibited insulin resistance on both normal chow and high-fat diets. These lipodystrophic mice also developed hypertension, cardiac hypertrophy, and cardiac dysfunction. Thus, isolated mitochondrial dysfunction in adipose tissue can lead a syndrome of lipodystrophy with metabolic syndrome and cardiovascular complications. © FASEB.

  5. The role of hormones of adipose tissue in the development pregnancy complications in obese women

    Directory of Open Access Journals (Sweden)

    2013-03-01

    Full Text Available Obesity in pregnancy is a risk factor for complications for both the mother and of the fetus. Adipose tissue hormones (leptin, adiponectin, resistin are secreted by the human placenta and regulate the function of trophoblast.The review presents data from the literature on the role of adipocytokines in the development of gestational diabetes and preeclampsia in obesity women. The article considers the criteria and algorithms for the diagnosis of gestational diabetes recommended by the World Health Organization and the International Association of research groups for diabetes and pregnancy.

  6. Generalized enchondromatosis with unusual complications of soft tissue calcifications and hemangiomas

    International Nuclear Information System (INIS)

    Kaibara, N.; Katsuki, I.; Hotokebuchi, T.; Takagishi, K.

    1982-01-01

    Generalized enchondromatosis is a newly delineated type of enchondromatosis. Radiographically there are multiple enchondromata in almost all metaphyses of the long and short tubular bones and the lesions are in almost the same stage of development with mild platyspondyly and skull deformity. The pelvic changes are characteristic and, together with the metaphyseal changes of the long and short tubular bones, are probably diagnostic of this disorder. The present case demonstrates advanced radiographic features of this disorder associated with unusual soft tissue calcifications and hemangiomas. The presence of hemangiomas in our case as well as three cases in the literature suggests this feature is more than a coincidence. (orig.)

  7. MO-D-BRF-01: Pediatric Treatment Planning II: The PENTEC Report On Normal Tissue Complications

    International Nuclear Information System (INIS)

    Constine, L; Hodgson, D; Bentzen, S

    2014-01-01

    With advances in multimodality therapy, childhood cancer cure rates approach 80%. However, both radiotherapy and chemotherapy may cause debilitating or even fatal ‘late effects’ that are critical to understand, mitigate, or prevent. QUANTEC identified the uncertainties relating to side-effects of adult treatments, but this is more complicated for children in whom a mosaic of tissues develops at different rates and temporal sequences. Childhood cancer survivors have long life expectancy and may develop treatmentinduced secondary cancers and severe organ/tissue injury decades after treatment. Collaborative long-term observational studies and clinical research programs for survivors of pediatric and adolescent cancer provide some dose-response data for follow-up periods exceeding 40 years. Data analysis is challenging due to the influence of both therapeutic and developmental variables. PENTEC is a group of radiation oncologists, pediatric oncologists, subsepcialty physicians, medical physicists, biomathematic modelers/statisticians, and epidemiologists charged with conducting a critical synthesis of existing literature aiming to: critically analyze radiation dose-volume effects on normal tissue tolerances as a function of age/development in pediatric cancer patients in order to inform treatment planning and improve outcomes for survivors; describe relevant physics issues specific to pediatric radiotherapy; propose dose-volumeoutcome reporting standards to improve the knowledge base to inform future treatment guidelines. PENTEC has developed guidelines for systematic literature reviews, data extraction tolls and data analysis. This education session will discuss:1. Special considerations for normal tissue radiation response of children/adolescents, e.g. the interplay between development and radiotherapy effects.2. Epidemiology of organ/tissue injuries and secondary cancers.3. Exploration of dose-response differences between children and adults4. Methodology for

  8. MO-D-BRF-01: Pediatric Treatment Planning II: The PENTEC Report On Normal Tissue Complications

    Energy Technology Data Exchange (ETDEWEB)

    Constine, L; Hodgson, D; Bentzen, S [University of Maryland, Baltimore, MD (United States)

    2014-06-15

    With advances in multimodality therapy, childhood cancer cure rates approach 80%. However, both radiotherapy and chemotherapy may cause debilitating or even fatal ‘late effects’ that are critical to understand, mitigate, or prevent. QUANTEC identified the uncertainties relating to side-effects of adult treatments, but this is more complicated for children in whom a mosaic of tissues develops at different rates and temporal sequences. Childhood cancer survivors have long life expectancy and may develop treatmentinduced secondary cancers and severe organ/tissue injury decades after treatment. Collaborative long-term observational studies and clinical research programs for survivors of pediatric and adolescent cancer provide some dose-response data for follow-up periods exceeding 40 years. Data analysis is challenging due to the influence of both therapeutic and developmental variables. PENTEC is a group of radiation oncologists, pediatric oncologists, subsepcialty physicians, medical physicists, biomathematic modelers/statisticians, and epidemiologists charged with conducting a critical synthesis of existing literature aiming to: critically analyze radiation dose-volume effects on normal tissue tolerances as a function of age/development in pediatric cancer patients in order to inform treatment planning and improve outcomes for survivors; describe relevant physics issues specific to pediatric radiotherapy; propose dose-volumeoutcome reporting standards to improve the knowledge base to inform future treatment guidelines. PENTEC has developed guidelines for systematic literature reviews, data extraction tolls and data analysis. This education session will discuss:1. Special considerations for normal tissue radiation response of children/adolescents, e.g. the interplay between development and radiotherapy effects.2. Epidemiology of organ/tissue injuries and secondary cancers.3. Exploration of dose-response differences between children and adults4. Methodology for

  9. Surveying the rate of tissue expander complications among reconstructive patients in Hazrat Fatima hospital between 1389-1391

    Directory of Open Access Journals (Sweden)

    Amirasadola Khajerahimi

    2016-05-01

    Full Text Available Background: Tissue expansion is a common reconstructive surgery especially in burned patients. This study has been designed to evaluate the rate of complications of this method in Hazrat Fatima Hospital between 1389-1391. Materials & Methods: In this cross sectional and retrospective study, 150 patients' records have been studied between 1389-1391 years, frequency rate and types of complications related to tissue expander have been surveyed in these patients. Results: Complications have been observed in about 7% of the patients included in this study. Exposure of tissue expander was the most common complication (81.8%. Other complications which are resulted from this issue are capsular contracture and infection. Age was the only factor which had significant relation with increasing complication among the other surveyed factors including age, sex, indication of operation, wound location and duration of anaesthesia.(p=0.033 Conclusion: The incidence of complication in patients that required tissue expander was not high and it was less than 10%. It should be noted that patient selection should be carefully in paediatric group and also strict observance of surgical principles is necessary to avoid complication.

  10. Dosimetric complication probability and acoustic analysis of vocal cord region in oropharyngeal carcinoma treated with voice-sparing intensity modulated radiotherapy

    International Nuclear Information System (INIS)

    Jain, S.; Gupta, T.; Agarwal, J.P.; Baccher, G.; Shrivastava, S.K.; Reenadevi; Master, J.

    2008-01-01

    Radiation to larynx has long been associated with speech and voice dysfunction. The objective is to study dosimetric parameters and complication probability of vocal cord region (VCR) and the effect of voice-sparing (VS) in the patients treated with intensity modulated radiotherapy (IMRT). The secondary objective is to describe the post-radiation acoustic voice characteristics and correlate them with the dosimetric parameters. (author)

  11. Aqueous Leaf Extract of Heliotropium Indicum Ameliorates Hyperglycaemia-Induced Tissue Complications in Albino Rats

    Directory of Open Access Journals (Sweden)

    Rasheed Bolaji Ibrahim

    2018-01-01

    Full Text Available Background: Heliotropium indicum is used by traditional medical practitioners in North Central Nigeria for the management of ailments including diabetes. However, the folkloric use of H. indicum as antidiabetic has been asserted, but its roles on the hyperglycemia-induced organ-specific complications are not yet scientifically proven. Thus, ameliorative effect of aqueous leaf extract of H. indicum on selected toxicological parameters in hyperglycaemic rats was investigated in this study. Methods: Twenty-five rats were randomized into five groups. The study was carried out at the Animal Holding Unit, Biochemistry Department, University of Ilorin in 2013. Four groups were intraperitoneally administered singly with 150 mg/kg b.wt of alloxan to induce hyperglycemia. The normal control (NC and hyperglycaemic control (HC groups were administered 1 ml distilled water, while the reference group (HR were administered 14.2 mg/kg b.wt of metformin and the test groups, H30 and H75 were administered 30 and 75 mg/kg b.wt, the extract respectively for fourteen days. Results: The significantly increased (P<0.05 serum concentrations of tissue membrane bound enzymes (ALT, AST, ACP and ALP, direct and total bilirubin, urea and creatinine in HC indicating compromised tissue structures and functions in HC were attenuated. The significantly (P<0.05 reduced serum total protein, globulin and albumin in HC were significantly increased by both doses of the extract. The ameliorative role of the extract at the test doses was supported by the histological assessment of liver and kidney of the animals. Conclusion: Aqueous leaf extract of H. indicum can be explored at the ethnobotanical dose of 30 and 75 mg/kg b.wt on the management of some of the tissue-specific disarrays associated with diabetes.

  12. Expressiveness and frequency differences of hip joint tissues pathomorphological changes in diseases complicated by femoroacetabular impingement syndrome

    Directory of Open Access Journals (Sweden)

    V. V. Grigorovsky

    2013-12-01

    of the development of symptoms leading to the necessity of correcting operations on the joint. Degrees of "femoral head articular surface deformation" in various nosologies essentially differ on frequency of occurrence of cases with certain expressiveness: if in patients with JSFCE only low degree of femoral head deformation occurs, in АNFH cases with high degree of expressiveness comprise over one third, that is connected, probably, with features of the basic pathological processes in femoral head spongiosa in this disease. Occurrence frequency of nonspecific synovitis cases of certain activity degree depends from primary nosology which has become complicated by FAI: among patients with АNFH synovitis of average or high degree was found significantly more frequent, than among patients with JSFCE in whom cases of low activity synovitis prevail. Conclusions. In the present work comparative research of all hip joint tissues was performed for the first time on rather big clinical-morphological material, with application of graded indices and the frequency analysis, degrees of pathological changes expressiveness are defined and distinctions of frequencies of occurrence in groups of comparison of patients with АNFH and JSFCE, complicated by FAI, were established.

  13. Portomesenteric venous thrombosis: A rare but probably under-reported complication of laparoscopic surgery: A case series

    Directory of Open Access Journals (Sweden)

    Yan Mei Goh

    2017-01-01

    Full Text Available Portomesenteric venous thrombosis (PMVT is a rare but well-reported complication following laparoscopic surgery. We present three cases of PMVT following laparoscopic surgery. Our first case is a 71-year-old morbidly obese woman admitted for elective laparoscopic giant hiatus hernia (LGHH repair. Post-operatively, she developed multi-organ dysfunction and computed tomography scan revealed portal venous gas and extensive small bowel infarct. The second patient is a 51-year-old man with known previous deep venous thrombosis who also had elective LGHH repair. He presented 8 weeks post-operatively with severe abdominal pain and required major bowel resection. Our third case is an 86-year-old woman who developed worsening abdominal tenderness 3 days after laparoscopic right hemicolectomy for adenocarcinoma and was diagnosed with an incidental finding of thrombus in the portal vein. She did not require further surgical intervention. The current guidelines for thromboprophylaxis follow-up in this patient group may not be adequate for the patients at risk. Hence, we propose prolonged period of thromboprophylaxis in the patients undergoing major laparoscopic surgery.

  14. Morphological, clinical and radiological aspects in diagnostics of bronchopulmonary diseases and their complications in children with dysplasia of connective tissue

    Directory of Open Access Journals (Sweden)

    Palchik S.M.

    2016-06-01

    Full Text Available The article provides an overview of the literature devoted to study of radiological, morphological and clinical aspects of diagnostics of respiratory diseases and their complications in children with dysplasia of connective tissue nowadays. We made an analysis of the role of connective tissue disorders in pathogenesis of bronchopulmonary diseases. Theoretically was substantiated the importance of radiological methods in early diagnostics of this disease in children.

  15. Identification of titanium in human tissues: probable role in pathologic processes

    International Nuclear Information System (INIS)

    Moran, C.A.; Mullick, F.G.; Ishak, K.G.; Johnson, F.B.; Hummer, W.B.

    1991-01-01

    Six cases of titanium dioxide exposure involving lung, skin, and synovium are described, with a review of the literature. The patients, four men and two women, were between the ages of 22 and 65 years. The pulmonary changes were characterized by fibrosis and numerous macrophages with abundant deposition of a black pigment. Adjacent areas of bronchopneumonia were also observed. In the skin a severe necrotizing lesion involving the subcutaneous tissue with extension to the muscle was observed in one case and a nonspecific inflammatory response was observed in another; both cases showed abundant black pigment deposition. Electron microscopy and energy dispersive x-ray analysis demonstrated the presence of large quantities of titanium in the pigment granules. There may be a combination of black pigment deposition and fibrosis, necrosis, or a xanthomatous or granulomatous reaction, that, together with negative results on special staining and culture studies for organisms, should raise the suspicion of titanium-associated injury and prompt the study of the affected tissues by x-ray analysis for positive identification

  16. Delayed-onset complications of facial soft tissue augmentation with permanent fillers in 85 patients

    NARCIS (Netherlands)

    Kadouch, Jonathan A.; Kadouch, Daniel J.; Fortuin, Shai; van Rozelaar, Leo; Karim, Refaat B.; Hoekzema, Rick

    2013-01-01

    To evaluate factors influencing the onset and type of adverse events in patients injected with permanent fillers in the face and to propose a therapeutic strategy for these complications. A prospectively attained series of 85 patients with delayed-onset complications after facial injection with

  17. External validation of a normal tissue complication probability model for radiation-induced hypothyroidism in an independent cohort

    DEFF Research Database (Denmark)

    Rønjom, Marianne F; Brink, Carsten; Bentzen, Søren M

    2015-01-01

    blood tests in the validation cohort relative to the original cohort. However, Pearson's correlation coefficients between model and clinical outcome were high: r = 0.97 estimated by the original model versus the original cohort, and r = 0.97 estimated by the original model versus the new cohort....... CONCLUSION: Dmean and Vthyroid were significant predictors of RIHT in both cohorts. The original NTCP model demonstrated external validity owing to high Pearson's correlation coefficients between estimated and observed incidence rates of RIHT in the original as well as in the validation cohort. This model...

  18. Delayed-onset complications of facial soft tissue augmentation with permanent fillers in 85 patients.

    Science.gov (United States)

    Kadouch, Jonathan A; Kadouch, Daniel J; Fortuin, Shai; van Rozelaar, Leo; Karim, Refaat B; Hoekzema, Rick

    2013-10-01

    To evaluate factors influencing the onset and type of adverse events in patients injected with permanent fillers in the face and to propose a therapeutic strategy for these complications. A prospectively attained series of 85 patients with delayed-onset complications after facial injection with permanent fillers underwent clinical follow-up and treatment of the complications. Lag times until onset and type of delayed-onset complication varied according to filler material. In 28% (n = 24) of the cases, patients reported the onset of complications after dental procedures, additional injections with fillers, or other invasive treatments in the facial area. Forty-eight (57%) patients required invasive treatment. Abscess formation was significantly more frequent in patients with human immunodeficiency virus infection and facial lipoatrophy (p = .001). The intrinsic characteristics of the injected filler and the immune status of the patient play important roles in the diversity of time of onset and type of delayed-onset adverse events observed. It seems that invasive facial or oral procedures in the vicinity of filler depots can provoke such complications. We propose a strategy for treating these complications and advise great caution when using permanent filling agents. © 2013 by the American Society for Dermatologic Surgery, Inc. Published by Wiley Periodicals, Inc.

  19. Probability distribution of dose rates in the body tissue as a function of the rhytm of Sr90 administration and the age of animals

    International Nuclear Information System (INIS)

    Rasin, I.M.; Sarapul'tsev, I.A.

    1975-01-01

    The probability distribution of tissue radiation doses in the skeleton were studied in experiments on swines and dogs. When introducing Sr-90 into the organism from the day of birth till 90 days dose rate probability distribution is characterized by one, or, for adult animals, by two independent aggregates. Each of these aggregates correspond to the normal distribution law

  20. Normal tissue complications after radiation therapy Las complicaciones de la radioterapia en los tejidos sanos

    Directory of Open Access Journals (Sweden)

    Jolyon H. Hendry

    2006-09-01

    Full Text Available This paper describes the biological mechanisms of normal tissue reactions after radiation therapy, with reference to conventional treatments, new treatments, and treatments in developing countries. It also describes biological reasons for the latency period before tissue complications arise, the relationship of dose to incidence, the effect of increasing the size of the irradiated volume, early and late tissue reactions, effects of changes in dose fractionation and dose rate, and combined chemotherapy and radiotherapy responses. Examples are given of increases in knowledge of clinical radiobiology from trials of new protocols. Potential modification to treatments include the use of biological response modifiers. The introduction of "response prediction" modifications to treatments might also be available in the near future. Finally, the paper points out that in some radiotherapy centers, the biologically-effective doses prescribed for combined brachytherapy and teletherapy treatment of cervix cancer are lower than those prescribed in other centers. This issue needs to be addressed further. The wealth of preclinical and clinical data has led to a much greater understanding of the biological basis to radiotherapy. This understanding has underpinned a variety of new approaches in radiotherapy, including both physical and biological strategies. There is also the important issue of treatment of a large number of cancers in developing countries, for which efficacious resource-sparing protocols are being continuously developed. A unified scoring system should be widely accepted as the new standard in reporting the adverse effects of radiation therapy. Likewise, late toxicity should be reported on an actuarial basis as a mandatory endpoint.En este artículo se describen los mecanismos biológicos que intervienen en las reacciones provocadas por la radioterapia, tanto con tratamientos convencionales como con los más nuevos, y los aplicados en países en

  1. Therapeutic options and postoperative wound complications after extremity soft tissue sarcoma resection and postoperative external beam radiotherapy.

    Science.gov (United States)

    Abouarab, Mohamed H; Salem, Iman L; Degheidy, Magdy M; Henn, Dominic; Hirche, Christoph; Eweida, Ahmad; Uhl, Matthias; Kneser, Ulrich; Kremer, Thomas

    2018-02-01

    Soft tissue sarcomas occur most commonly in the lower and upper extremities. The standard treatment is limb salvage surgery combined with radiotherapy. Postoperative radiotherapy is associated with wound complications. This systematic review aims to summarise the available evidence and review the literature of the last 10 years regarding postoperative wound complications in patients who had limb salvage surgical excision followed by direct closure vs flap coverage together with postoperative radiotherapy and to define the optimal timeframe for adjuvant radiotherapy after soft tissue sarcomas resection and flap reconstruction. A literature search was performed using PubMed. The following keywords were searched: limb salvage, limb-sparing, flaps, radiation therapy, radiation, irradiation, adjuvant radiotherapy, postoperative radiotherapy, radiation effects, wound healing, surgical wound infection, surgical wound dehiscence, wound healing, soft tissue sarcoma and neoplasms. In total, 1045 papers were retrieved. Thirty-seven articles were finally selected after screening of abstracts and applying dates and language filters and inclusion and exclusion criteria. Plastic surgery provides a vast number of reconstructive flap procedures that are directly linked to decreasing wound complications, especially with the expectant postoperative radiotherapy. This adjuvant radiotherapy is better administered in the first 3-6 weeks after reconstruction to allow timely wound healing and avoid local recurrence. © 2017 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

  2. Safety and Efficacy of Intrapleural Tissue Plasminogen Activator and DNase during Extended Use in Complicated Pleural Space Infections

    Directory of Open Access Journals (Sweden)

    Jason R. McClune

    2016-01-01

    Full Text Available The use of intrapleural therapy with tissue plasminogen activator and DNase improves outcomes in patients with complicated pleural space infections. However, little data exists for the use of combination intrapleural therapy after the initial dosing period of six doses. We sought to describe the safety profile and outcomes of intrapleural therapy beyond this standard dosing. A retrospective review of patients receiving intrapleural therapy with tissue plasminogen activator and DNase was performed at two institutions. We identified 101 patients from January 2013 to August 2015 receiving intrapleural therapy for complicated pleural space infection. The extended use of intrapleural tissue plasminogen activator and DNase therapy beyond six doses was utilized in 20% (20/101 of patients. The mean number of doses in those undergoing extended dosing was 9.8 (range of 7–16. Within the population studied there appears to be no statistically significant increased risk of complications, need for surgical referral, or outcome differences when comparing those receiving standard or extended dosing intrapleural therapy. Future prospective study of intrapleural therapy as an alternative option for patients who fail initial pleural drainage and are unable to tolerate/accept a surgical intervention appears a potential area of study.

  3. Three-dimensional radiotherapy planning system for esophageal tumors: comparison of treatment techniques and analysis of probability of complications; Planejamento tridimensional para radioterapia de tumores de esofago: comparacao de tecnicas de tratamento e analise de probabilidade de complicacoes

    Energy Technology Data Exchange (ETDEWEB)

    Justino, Pitagoras Baskara; Carvalho, Heloisa de Andrade; Ferauche, Debora; Ros, Renato [Sao Paulo Uni., SP (Brazil). Hospital das Clinicas. Instituto de Radioterapia (InRad)]. E-mail: pitagorasb@hotmail.com

    2003-06-01

    Radiotherapy techniques for esophageal cancer were compared using a three-dimensional planning system. We studied the following treatment techniques used for a patient with squamous cell carcinoma of the middle third of the esophagus: two antero-posterior and two latero-lateral parallel opposed fields, three fields ('Y' and 'T'), and four fields ('X'). Dose-volume histograms were obtained considering spinal cord and lungs as organs at risk. Analysis was performed comparing doses in these organs as recommended by the Normal Tissue Complication Probability (NTCP) and Tumor Control Probability (TCP). When only the lungs were considered the best technique was two antero-posterior parallel opposed fields. The spinal cord was best protected using latero-lateral fields. We suggest the combination of at least two treatment techniques: antero-posterior fields with 'Y' or 'T' techniques, or latero-lateral fields in order to balance the doses in the lungs and the spinal cord. Another option may be the use of any of the three-field techniques during the whole treatment. (author)

  4. Connective Tissue Disorders and Cardiovascular Complications: The indomitable role of Transforming Growth Factor-beta signaling

    Science.gov (United States)

    Wheeler, Jason B.; Ikonomidis, John S.; Jones, Jeffrey A.

    2015-01-01

    Marfan Syndrome (MFS) and Loeys-Dietz Syndrome (LDS) represent heritable connective tissue disorders that cosegregate with a similar pattern of cardiovascular defects (thoracic aortic aneurysm, mitral valve prolapse/regurgitation, and aortic dilatation with regurgitation). This pattern of cardiovascular defects appears to be expressed along a spectrum of severity in many heritable connective tissue disorders and raises suspicion of a relationship between the normal development of connective tissues and the cardiovascular system. Given the evidence of increased transforming growth factor-beta (TGF-β) signaling in MFS and LDS, this signaling pathway may represent the common link in this relationship. To further explore this hypothetical link, this chapter will review the TGF-β signaling pathway, heritable connective tissue syndromes related to TGF-β receptor (TGFBR) mutations, and discuss the pathogenic contribution of TGF-β to these syndromes with a primary focus on the cardiovascular system. PMID:24443024

  5. Adipose tissue mitochondrial dysfunction triggers a lipodystrophic syndrome with insulin resistance, hepatosteatosis, and cardiovascular complications

    OpenAIRE

    Vernochet, Cecile; Damilano, Federico; Mourier, Arnaud; Bezy, Olivier; Mori, Marcelo A.; Smyth, Graham; Rosenzweig, Anthony; Larsson, Nils-Göran; Kahn, C. Ronald

    2014-01-01

    Mitochondrial dysfunction in adipose tissue occurs in obesity, type 2 diabetes, and some forms of lipodystrophy, but whether this dysfunction contributes to or is the result of these disorders is unknown. To investigate the physiological consequences of severe mitochondrial impairment in adipose tissue, we generated mice deficient in mitochondrial transcription factor A (TFAM) in adipocytes by using mice carrying adiponectin-Cre and TFAM floxed alleles. These adiponectin TFAM-knockout (adipo-...

  6. Radiotherapy and breast reconstruction: complications and cosmesis with TRAM versus tissue expander/implant

    International Nuclear Information System (INIS)

    Chawla, Ashish K.; Kachnic, Lisa A.; Taghian, Alphonse G.; Niemierko, Andrzej; Zapton, Daniel T.; Powell, Simon N.

    2002-01-01

    Purpose: Radiotherapy (RT) has an important role in breast cancer treatment after modified radical mastectomy. Many of these patients also undergo breast reconstruction. We reviewed our institutions' experience to determine the outcome of patients treated with breast reconstruction and RT. Methods and Materials: Between 1981 and 1999, 48 breast cancer patients underwent modified radical mastectomy, breast reconstruction, and ipsilateral breast RT during their treatment course. Reconstruction either preceded or followed RT. Autologous reconstruction with a transverse rectus abdominus myocutaneous (TRAM) flap was performed in 30 patients, and 18 underwent expander and implant (E/I) reconstruction. The primary endpoint was the quality of the reconstructed, irradiated breast, as measured by analyzing the actuarial incidence of complications. The cosmetic outcome was also assessed by multidisciplinary review of the follow-up visits. Results: The median follow-up from reconstruction was 32 months. The actuarial 2-year complication rate was 53% for patients receiving E/I vs. 12% for those receiving TRAM reconstruction (p<0.01). No other patient or treatment-related factors had a significant impact on complications. The cosmetic outcome was also significantly better in the TRAM subgroup than in the E/I subgroup. Conclusion: The tolerance and cosmetic outcome of breast reconstruction for breast cancer patients in irradiated sites depends significantly on the type of reconstruction used

  7. Complicated acute appendicitis presenting as a rapidly progressive soft tissue infection of the abdominal wall: a case report.

    Science.gov (United States)

    Beerle, Corinne; Gelpke, Hans; Breitenstein, Stefan; Staerkle, Ralph F

    2016-12-01

    We report a case of a rare complication of acute appendicitis with perforation through the abdominal wall. The case points out that an intraabdominal origin should be considered in patients presenting with rapidly spreading soft tissue infections of the trunk. A 58-year-old European woman presented to our hospital with a 1-week history of severe abdominal pain accompanied by rapidly spreading erythema and emphysema of the lower abdomen. On admission, the patient was in septic shock with leukocytosis and elevation of C-reactive protein. Among other diagnoses, necrotizing fasciitis was suspected. Computed tomography showed a large soft tissue infection with air-fluid levels spreading through the lower abdominal wall. During the operation, we found a perforated appendicitis breaking through the fascia and causing a rapidly progressive soft tissue infection of the abdominal wall. Appendicitis was the origin of the soft tissue infection. The abdominal wall was only secondarily involved. Even though perforated appendicitis as an etiology of a rapidly progressive soft tissue infection of the abdominal wall is very rare, it should be considered in the differential diagnosis of abdominal wall cellulitis. The distinction between rapidly spreading subcutaneous infection with abscess formation and early onset of necrotizing fasciitis is often difficult and can be confirmed only by surgical intervention.

  8. Pulmonary infiltration with eosinophilia complicated with mucosa-associated lymphoid tissue lymphoma: A case report.

    Science.gov (United States)

    Liu, Yin; Tangsun, Yinyan; Xiao, Yonglong; Zhang, Deping; Cao, Min

    2016-09-01

    Tissue eosinophilia is rarely observed in cases of non-Hodgkin's lymphoma of B cell origin. The present study describes a rare case of mucosa-associated lymphoid tissue (MALT) lymphoma, which was initially misdiagnosed as eosinophilic pneumonia. The initial diagnosis was formed based on the results of chest radiography, peripheral eosinophilia tests and bronchoalveolar lavage, and the clinical course of the patient. Following administration of methylprednisolone (40 mg/day) for 4 days and oral administration of prednisolone (30 mg/day), the clinical course rapidly improved and the eosinophil count immediately decreased a to normal level. However, abnormal shadows observed on computed tomography (CT) scans of the chest did not diminish. At 6 months after the initiation of treatment, CT-guided percutaneous lung biopsy was performed, and a final diagnosis of primary pulmonary mucosa-associated lymphoid tissue lymphoma was made based on immunohistochemical examination. Primary lung MALT lymphoma remains a rare entity, with an indolent course and a reasonably favorable prognosis, whose diagnosis may be challenging.

  9. Risk Probabilities

    DEFF Research Database (Denmark)

    Rojas-Nandayapa, Leonardo

    Tail probabilities of sums of heavy-tailed random variables are of a major importance in various branches of Applied Probability, such as Risk Theory, Queueing Theory, Financial Management, and are subject to intense research nowadays. To understand their relevance one just needs to think...... analytic expression for the distribution function of a sum of random variables. The presence of heavy-tailed random variables complicates the problem even more. The objective of this dissertation is to provide better approximations by means of sharp asymptotic expressions and Monte Carlo estimators...

  10. Three-dimensional multislice spiral computed tomographic angiography: a potentially useful tool for safer free tissue transfer to complicated regions

    DEFF Research Database (Denmark)

    Demirtas, Yener; Cifci, Mehmet; Kelahmetoglu, Osman

    2009-01-01

    Three-dimensional multislice spiral computed tomographic angiography (3D-MSCTA) is a minimally invasive method of vascular mapping. The aim of this study was to evaluate the clinical usefulness of this imaging technique in delineating the recipient vessels for safer free tissue transfer to compli......Three-dimensional multislice spiral computed tomographic angiography (3D-MSCTA) is a minimally invasive method of vascular mapping. The aim of this study was to evaluate the clinical usefulness of this imaging technique in delineating the recipient vessels for safer free tissue transfer...... be kept in mind, especially inthe patients with peripheral vascular disease. 3D-MSCTA has the potential to replace digital subtraction angiography for planning of microvascular reconstructions and newer devices with higher resolutions will probably increase the reliability of this technique. (c) 2009...

  11. Expression of von Willebrand factor and caldesmon in the placental tissues of pregnancies complicated with intrauterine growth restriction.

    Science.gov (United States)

    Göksever Çelik, Hale; Uhri, Mehmet; Yildirim, Gökhan

    2017-11-02

    The decreased placental perfusion is the underlying reason for intrauterine growth restriction that in turn leads to reduced placental perfusion and ischemia. However, there are several issues to be understood in the pathophysiology of intrauterine growth restriction. We aimed to study whether any compensatory response in placental vascular bed occur in pregnancies complicated with intrauterine growth restriction by the immunohistochemical staining of von Willebrand factor and caldesmon in placental tissues. A total of 103 pregnant women was enrolled in the study including 50 patients who were complicated with IUGR and 50 uncomplicated control patients. The study was designed in a prospective manner. All placentas were also stained with von Willebrand factor and caldesmon monoclonal kits. The immunohistochemical staining of von Willebrand factor and caldesmon expressions in placental tissues were different between normal and intrauterine growth restriction group. The percentages of 2+ and 3+ von Willebrand factor expression were higher in the intrauterine growth restriction group comparing with the normal group, although the difference was not statistically significant. The intensity of caldesmon expression was significantly lower in the intrauterine growth restriction group in comparison with the normal group (p intrauterine growth restriction which is a hypoxic condition. But newly formed vessels are immature and not strong enough. Our study is important to clarify the pathophysiology and placental compensatory responses in intrauterine growth restriction.

  12. Cerebral gray matter volume losses in essential tremor: A case-control study using high resolution tissue probability maps.

    Science.gov (United States)

    Cameron, Eric; Dyke, Jonathan P; Hernandez, Nora; Louis, Elan D; Dydak, Ulrike

    2018-03-10

    Essential tremor (ET) is increasingly recognized as a multi-dimensional disorder with both motor and non-motor features. For this reason, imaging studies are more broadly examining regions outside the cerebellar motor loop. Reliable detection of cerebral gray matter (GM) atrophy requires optimized processing, adapted to high-resolution magnetic resonance imaging (MRI). We investigated cerebral GM volume loss in ET cases using automated segmentation of MRI T1-weighted images. MRI was acquired on 47 ET cases and 36 controls. Automated segmentation and voxel-wise comparisons of volume were performed using Statistical Parametric Mapping (SPM) software. To improve upon standard protocols, the high-resolution International Consortium for Brain Mapping (ICBM) 2009a atlas and tissue probability maps were used to process each subject image. Group comparisons were performed: all ET vs. Controls, ET with head tremor (ETH) vs. Controls, and severe ET vs. An analysis of variance (ANOVA) was performed between ET with and without head tremor and controls. Age, sex, and Montreal Cognitive Assessment (MoCA) score were regressed out from each comparison. We were able to consistently identify regions of cerebral GM volume loss in ET and in ET subgroups in the posterior insula, superior temporal gyri, cingulate cortex, inferior frontal gyri and other occipital and parietal regions. There were no significant increases in GM volume in ET in any comparisons with controls. This study, which uses improved methodologies, provides evidence that GM volume loss in ET is present beyond the cerebellum, and in fact, is widespread throughout the cerebrum as well. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. Identification of complications in mastectomy with immediate reconstruction using tissue expanders and permanent implants for breast cancer patients.

    Science.gov (United States)

    Ota, Daisuke; Fukuuchi, Atsushi; Iwahira, Yoshiko; Kato, Takao; Takeuchi, Masashi; Okamoto, Joji; Nishi, Tsunehiro

    2016-05-01

    Since complications of postmastectomy breast reconstruction may reduce patient satisfaction, we investigated complications of reconstruction with tissue expanders (TEs), particularly surgical site infections requiring TE/permanent implant (PI) removal. A retrospective review was performed of 234 primary breast cancer patients undergoing 239 postmastectomy breast reconstructions with TEs/PIs from 1997 to 2009. Clinicopathological findings and postoperative complications, particularly infections, were analyzed. Data were analyzed by the Chi-square test and a multivariate logistic regression model. TE infection risk factors considered for model inclusion were excisional biopsy, (neo) adjuvant chemotherapy, lymph node resection, body mass index (BMI), simultaneous bilateral reconstructions, and seroma aspiration. Removal of TEs/PIs was observed in 15.5% (37/239) of reconstructions, and 18/37 underwent re-reconstructions. Of the 19/37 reconstructions that were not achieved completely, the most frequent reason was TE infection (11 reconstructions). The completion rate was 92% (220/239 reconstructions) and it was significantly higher in reconstructions without TE infection than with infection (96 vs. 54%, p breast reconstruction, prevention of TE infection plays a key role. We should reduce unnecessary seroma aspirations and delay elevation/exercise of the ipsilateral arm.

  14. Probability theory

    CERN Document Server

    Dorogovtsev, A Ya; Skorokhod, A V; Silvestrov, D S; Skorokhod, A V

    1997-01-01

    This book of problems is intended for students in pure and applied mathematics. There are problems in traditional areas of probability theory and problems in the theory of stochastic processes, which has wide applications in the theory of automatic control, queuing and reliability theories, and in many other modern science and engineering fields. Answers to most of the problems are given, and the book provides hints and solutions for more complicated problems.

  15. Sjogren syndrome complicated by mucosa-associated lymphoid tissue lymphoma and lymphocytic interstitial pneumonia

    Directory of Open Access Journals (Sweden)

    Fatma eAhmed

    2015-08-01

    Full Text Available Sjogren Syndrome (SS is an autoimmune disease with exocrine glands dysfunction and multiorgan involvement. It is associated with increased risk of lymphoproliferative disorders, especially B-cell marginal zone lymphoma. While the role of F-18 Flurodoxyglucose position emission tomography/CT (F-18 FDG PET/CT for evaluation of lymphoma has been established, its use in patients with a chronic history of SS to evaluate for possible lymphoproliferative disorders or multiorgan involvement is limited. We present a case of chronic SS in which F-18 FDG PET/CT demonstrated FDG avid intraparotid and cervical lymph nodes pathologically proven to be Mucosa-associated lymphoid tissue (MALT lymphoma. In addition, the patient had bibasilar cystic changes consistent with lymphocytic interstitial pneumonia (LIP.

  16. The Effect of Radiation on Complication Rates and Patient Satisfaction in Breast Reconstruction using Temporary Tissue Expanders and Permanent Implants.

    Science.gov (United States)

    Anker, Christopher J; Hymas, Richard V; Ahluwalia, Ravinder; Kokeny, Kristine E; Avizonis, Vilija; Boucher, Kenneth M; Neumayer, Leigh A; Agarwal, Jayant P

    2015-01-01

    The optimal method of reconstruction following mastectomy for breast cancer patients receiving radiation therapy (RT) is controversial. This study evaluated patient satisfaction and complication rates among patients who received implant-based breast reconstruction. The specific treatment algorithm analyzed included patients receiving mastectomy and immediate temporary tissue expander (TE), followed by placement of a permanent breast implant (PI). If indicated, RT was delivered to the fully expanded TE. Records of 218 consecutive patients with 222 invasive (85%) or in situ (15%) breast lesions from the Salt Lake City region treated between 1998 and 2009 were retrospectively reviewed, 28% of whom received RT. Median RT dose was 50.4 Gy, and 41% received a scar boost at a median dose of 10 Gy. Kaplan-Meier analyses were performed to evaluate the cumulative incidence of surgical complications, including permanent PI removal. Risk factors associated with surgical events were analyzed. To evaluate cosmetic results and patient satisfaction, an anonymous survey was administered. Mean follow-up was 44 months (range 6-144). Actuarial 5-year PI removal rates for non-RT and RT patients were 4% and 22%, respectively. On multivariate analysis (MVA), the only factor associated with PI removal was RT (p = 0.009). Surveys were returned describing the outcomes of 149 breasts. For the non-RT and RT groups, those who rated their breast appearance as good or better were 63% versus 62%, respectively. Under 1/3 of each group was dissatisfied with their reconstruction. RT did not significantly affect patient satisfaction scores, but on MVA RT was the only factor associated with increased PI removal. This reconstruction technique may be considered an acceptable option even if RT is needed, but the increased complication risk with RT must be recognized. © 2015 Wiley Periodicals, Inc.

  17. Distribution and probable physiological role of esterases in reproductive, digestive, and fat-body tissues of the adult cotton boll weevil, Anthonomus grandis Boh.

    Science.gov (United States)

    Jones, B R; Bancroft, H R

    1986-06-01

    Polyacrylamide gel electrophoresis was used to examine gut, Malpighian tube, fat-body, testes, and ovarioles tissues of the adult cotton boll weevil, Anthonomus grandis Boh. Esterases for which the inheritance has been reported previously by Terranova using whole-body homogenates were detected in dissected tissues and the probable physiological function of each allozyme is suggested. EST-1 occurs most frequently in ovarioles and female fat bodies. EST-2 is most often found in fat bodies and may be important in lipid turnover. No sex difference was observed. EST-3S is found in fat bodies and reproductive tissue, while EST-3F is always located in gut tissues, indicating that EST-3 is not controlled by a single autosomal locus with two codominant alleles as previously reported. EST-4, the most abundant esterase, can be detected in gut tissue at any age and is probably involved in digestion. EST-5 contains four allozymes which appear most frequently in testes and may be important during reproduction.

  18. Safety and Efficacy of Tissue Plasminogen Activator and DNase for Complicated Pleural Effusions Secondary to Abdominal Pathology.

    Science.gov (United States)

    Majid, Adnan; Ochoa, Sebastian; Chatterji, Sumit; Fernandez-Bussy, Sebastian; Kheir, Fayez; Rivera, Estefania; Cheng, George; Folch, Erik

    2017-03-01

    Exudative pleural effusions may arise secondary to inflammation of intra-abdominal structures. Pleural space loculations can complicate these effusions, preventing adequate chest tube drainage and leading to consideration of surgical intervention. Previous studies have demonstrated that intrapleural administration of tissue plasminogen activator (tPA) combined with human recombinant DNase can improve fluid drainage and reduce surgery for patients with loculated parapneumonic effusions; however, the efficacy of this treatment has not been evaluated for complicated pleural effusions attributed to intra-abdominal inflammation. We assessed the safety and efficacy of tPA/DNase for 17 pleural effusions associated with nonmalignant intra-abdominal pathology that did not drain adequately after placement of one or more chest tubes. Efficacy was measured by comparing post- to pretreatment fluid drainage rates, volumetric assessment of pleural fluid on radiographic images before and after treatment, and clinical improvement, including the need for surgical intervention. Symptomatic relief was assessed using the Borg scale for breathlessness. After a median of two doses of tPA/DNase, 23.5% of patients had chest pain and none had pleural bleeding. The volume of pleural fluid drained increased from a median of 325 ml to 890 ml per 24 hours after therapy (P = 0.018). The area of pleural space opacity on chest radiographs decreased from a median of 42.8-17.8% of the hemithorax (P = 0.001). tPA/DNase reduced the pleural fluid volume on chest computed tomographic imaging from a median of 294.4 ml to 116.1 ml. Borg scores improved from a median of 3 (interquartile range = 1-6) to 0 (interquartile range = 0-2) after therapy (P = 0.001). The median duration of chest tube placement and hospital stay were 4 and 11 days, respectively. Two patients required surgical intervention for lung entrapment. Overall, treatment was considered successful for 88.2% of patients

  19. Localized pulmonary crystal-storing histiocytosis complicating pulmonary mucosa-associated lymphoid tissue lymphoma presenting with multiple mass lesions.

    Science.gov (United States)

    Kokuho, Nariaki; Terasaki, Yasuhiro; Kunugi, Shinobu; Onda, Naomi; Urushiyama, Hirokazu; Terasaki, Mika; Hino, Mitsunori; Gemma, Akihiko; Hatori, Tsutomu; Shimizu, Akira

    2017-07-01

    Crystal-storing histiocytosis (CSH) is an uncommon finding in lymphoplasmacytic disorders that presents histiocytes with abnormal intralysosomal accumulations of immunoglobulin light chains as crystals of unknown etiology. A 38-year-old woman with antiphospholipid syndrome had a surgical lung biopsy because of multiple lung mass lesions. In a right middle lobe lesion, lymphoplasmacytic cells had a monocytoid appearance, destructive lymphoepithelial lesions, and positive immunoglobulin heavy chain (IGH) gene rearrangements. A right upper lobe lesion manifested proliferating rounded histiocytes with abundant, deeply eosinophilic cytoplasm and negative IGH gene rearrangements. Electron microscopy and mass spectrometry revealed a case of pulmonary CSH: abnormal proliferation of the immunoglobulin κ chain of a variable region that may be crystallized within plasma cells and histiocytes. We report a rare case of localized pulmonary CSH complicating pulmonary mucosa-associated lymphoid tissue lymphoma with multiple mass lesions. We demonstrate advances in the understanding of the pathogenesis of CSH by various analyses of these lesions. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Epidemiology and Outcomes of Complicated Skin and Soft Tissue Infections among Inpatients in Southern China from 2008 to 2013.

    Directory of Open Access Journals (Sweden)

    Xiaoyan Li

    Full Text Available Complicated skin and soft tissue infections (cSSTI are some of the most commonly treated infections in hospitals, and place heavy economic burdens on patients and society. Here we report the findings from an analysis of cSSTI based on a retrospective study which was conducted within the Chinese inpatient population. We focused our research on the analysis of the patient population, antibiotic treatment, clinical outcome and economic burden. The study population comprised 527 selected patients hospitalized between 2008 and 2013. Among the hospitalizations with microbiological diagnoses, 61.41% (n = 113 were diagnosed as infected with Gram-positive bacteria, while 46.20% (n = 85 were infected with Gram-negative bacteria. The most commonly found Gram-positive bacteria was Staphylococcus aureus (40.76%, n = 75, and the most common Gram-negative bacteria was Escherichia coli (14.13%, n = 26. About 20% of the Staphylococcus aureus were methicillin-resistant. The resistance rate of isolated Staphylococcus aureus or Escherichia coli to penicillin was around 90%; in contrast, the resistance rate to vancomycin, linezolid or imipenem was low (<20%. A large percentage of patients were treated with cephalosporins and fluoroquinolones, while vancomycin and imipenem were also included to treat drug-resistant pathogens. Over half of the hospitalizations (58.43%, n = 336 experienced treatment modifications. The cost to patients with antibiotic modifications was relatively higher than to those without. In conclusion, our study offers an analysis of the disease characteristics, microbiological diagnoses, treatment patterns and clinical outcomes of cSSTI in four hospitals in Guangdong Province, and sheds lights on the current clinical management of cSSTI in China.

  1. Soft-tissue Necrosis Complicating Bone-cement Filling in a Patient with Proximal Tibia Giant cell Tumour and Co-morbid Depressive Illness

    Directory of Open Access Journals (Sweden)

    Sagar Narang

    2013-12-01

    Full Text Available Giant-cell tumors are common around the knee. Proximal tibia is a challenging location for limb-salvage due to paucity of soft-tissue cover. Bone cement has been used in treatment of giant-cell tumors after curettage. Tissue irritant properties of its monomer and exothermic reaction involved in polymerization may compromise surgical outcome to varying degrees. Preoperative planning and intra-operative positioning during cementing process are of importance to avoid complications. Co-occurrence of psychiatric illness in tumor patients should be managed by psychiatric counselling and drug therapy. This case has been presented to suggest measures for preventing soft-tissue complications during cement filling in proximal tibia, and for dealing with concomitant psychiatric problems for a holistic improvement in tumor patients.

  2. Preoperative Radiotherapy and Wide Resection for Soft Tissue Sarcomas: Achieving a Low Rate of Major Wound Complications with the Use of Flaps. Results of a Single Surgical Team.

    Science.gov (United States)

    Chan, Lester Wai Mon; Imanishi, Jungo; Grinsell, Damien Glen; Choong, Peter

    2017-01-01

    Surgery in combination with radiotherapy (RT) has become the standard of care for most soft tissue sarcomas. The choice between pre- and postoperative RT is controversial. Preoperative RT is associated with a 32-35% rate of major wound complications (MWC) and 16-25% rate of reoperation. The role of vascularized soft tissue "flaps" in reducing complications is unclear. We report the outcomes of patients treated with preoperative RT, resection, and flap reconstruction. 122 treatment episodes involving 117 patients were retrospectively reviewed. All patients were treated with 50.4 Gy of external beam radiation. Surgery was performed at 4-8 weeks after completion of RT by the same combination of orthopedic oncology and plastic reconstructive surgeon. Defects were reconstructed with 64 free and 59 pedicled/local flaps. 30 (25%) patients experienced a MWC and 17 (14%) required further surgery. 20% of complications were exclusively related to the donor site. There was complete or partial loss of three flaps. There was no difference in the rate of MWC or reoperation for complications with respect to age, sex, tumor site, previous unplanned excision, tumor grade, depth, and type of flap. Tumor size ≥8 cm was associated with a higher rate of reoperation (11/44 vs 6/78; P  = 0.008) but the rate of MWC was not significant (16/44 vs 14/78; P  = 0.066). The use of soft tissue flaps is associated with a low rate of MWC and reoperation. Our results suggest that a high rate of flap usage may be required to observe a reduction in complication rates.

  3. Preoperative Radiotherapy and Wide Resection for Soft Tissue Sarcomas: Achieving a Low Rate of Major Wound Complications with the Use of Flaps. Results of a Single Surgical Team

    Directory of Open Access Journals (Sweden)

    Lester Wai Mon Chan

    2018-01-01

    Full Text Available BackgroundSurgery in combination with radiotherapy (RT has become the standard of care for most soft tissue sarcomas. The choice between pre- and postoperative RT is controversial. Preoperative RT is associated with a 32–35% rate of major wound complications (MWC and 16–25% rate of reoperation. The role of vascularized soft tissue “flaps” in reducing complications is unclear. We report the outcomes of patients treated with preoperative RT, resection, and flap reconstruction.Patients and methods122 treatment episodes involving 117 patients were retrospectively reviewed. All patients were treated with 50.4 Gy of external beam radiation. Surgery was performed at 4–8 weeks after completion of RT by the same combination of orthopedic oncology and plastic reconstructive surgeon. Defects were reconstructed with 64 free and 59 pedicled/local flaps.Results30 (25% patients experienced a MWC and 17 (14% required further surgery. 20% of complications were exclusively related to the donor site. There was complete or partial loss of three flaps. There was no difference in the rate of MWC or reoperation for complications with respect to age, sex, tumor site, previous unplanned excision, tumor grade, depth, and type of flap. Tumor size ≥8 cm was associated with a higher rate of reoperation (11/44 vs 6/78; P = 0.008 but the rate of MWC was not significant (16/44 vs 14/78; P = 0.066.ConclusionThe use of soft tissue flaps is associated with a low rate of MWC and reoperation. Our results suggest that a high rate of flap usage may be required to observe a reduction in complication rates.

  4. Antibacterial Treatment of Meticillin-Resistant Staphylococcus Aureus Complicated Skin and Soft Tissue Infections: a Cost and Budget Impact Analysis in Greek Hospitals

    OpenAIRE

    Athanasakis, Kostas; Petrakis, Ioannis; Ollandezos, Mark; Tsoulas, Christos; Patel, Dipen A.; Karampli, Eleftheria; Kyriopoulos, John

    2014-01-01

    Introduction Meticillin-resistant staphylococcus aureus (MRSA) is an important cause of antimicrobial-resistant infections worldwide. Its prevalence remains high in the Greek hospital setting. Complicated skin and soft tissue infections (cSSTIs) due to MRSA are associated with prolonged hospitalization, additional healthcare costs and significant morbidity. The purpose of this study was to conduct a cost analysis and a budget impact analysis relative to different management scenarios for MRSA...

  5. [Morphological characteristics of kidneys connective tissue of mature fetuses and newborns from mothers, whose pregnancy was complicated by preeclampsia of varying degrees of severity].

    Science.gov (United States)

    Sorokina, Iryna V; Myroshnychenko, Mykhailo S; Kapustnyk, Nataliia V; Khramova, Tetyana O; Dehtiarova, Oksana V; Danylchenko, Svitlana I

    2018-01-01

    Introduction: The kidneys connective tissue condition in the antenatal period affects the formation of tissues and it changes with the development of various general pathological processes in this organ. The aim of the study was to identify the morphological features of kidneys connective tissue of fetuses and newborns from mothers whose pregnancy was complicated by preeclampsia of varying degrees of severity. Materials and methods: The material of the study was the tissue of kidneys of mature fetuses and newborns from mothers with physiological pregnancy (28 cases), as well as from mothers whose pregnancy was complicated by preeclampsia of varying degrees of severity (78 cases). Immunohistochemical study was performed by an indirect Coons method according to M. Brosman's technique using monoclonal antibodies to collagen type I, III and IV. Results: The kidneys connective tissue of fetuses and newborns developing under the maternal preeclampsia conditions is characterized by the qualitative and quantitative changes that indicate the development of sclerotic processes in this organ, the severity of which increase with the age and with the increase of the maternal preeclampsia severity. Qualitative changes are characterized by an increase of the fibrous component, thickening of the bundles of connective tissue fibers, and a decrease in the distance between them. Quantitative changes are characterized by a pronounced predominance of collagen fibers over elastic fibers, almost total absence in some field of view elastic fibers and the violation of the content of collagen type I, III and IV. Conclusion: Maternal preeclampsia underlies the development of qualitative and quantitative changes in kidneys connective tissue of fetuses and newborns, which as a result will lead to disruption of the functions of these organs in such children.

  6. Normal tissue complication models for clinically relevant acute esophagitis (≥ grade 2) in patients treated with dose differentiated accelerated radiotherapy (DART-bid)

    International Nuclear Information System (INIS)

    Zehentmayr, Franz; Söhn, Matthias; Exeli, Ann-Katrin; Wurstbauer, Karl; Tröller, Almut; Deutschmann, Heinz; Fastner, Gerd; Fussl, Christoph; Steininger, Philipp; Kranzinger, Manfred; Belka, Claus; Studnicka, Michael; Sedlmayer, Felix

    2015-01-01

    One of the primary dose-limiting toxicities during thoracic irradiation is acute esophagitis (AE). The aim of this study is to investigate dosimetric and clinical predictors for AE grade ≥ 2 in patients treated with accelerated radiotherapy for locally advanced non-small cell lung cancer (NSCLC). 66 NSCLC patients were included in the present analysis: 4 stage II, 44 stage IIIA and 18 stage IIIB. All patients received induction chemotherapy followed by dose differentiated accelerated radiotherapy (DART-bid). Depending on size (mean of three perpendicular diameters) tumors were binned in four dose groups: <2.5 cm 73.8 Gy, 2.5–4.5 cm 79.2 Gy, 4.5–6 cm 84.6 Gy, >6 cm 90 Gy. Patients were treated in 3D target splitting technique. In order to estimate the normal tissue complication probability (NTCP), two Lyman models and the cutoff-logistic regression model were fitted to the data with AE ≥ grade 2 as statistical endpoint. Inter-model comparison was performed with the corrected Akaike information criterion (AIC c ), which calculates the model’s quality of fit (likelihood value) in relation to its complexity (i.e. number of variables in the model) corrected by the number of patients in the dataset. Toxicity was documented prospectively according to RTOG. The median follow up was 686 days (range 84–2921 days), 23/66 patients (35 %) experienced AE ≥ grade 2. The actuarial local control rates were 72.6 % and 59.4 % at 2 and 3 years, regional control was 91 % at both time points. The Lyman-MED model (D50 = 32.8 Gy, m = 0.48) and the cutoff dose model (D c = 38 Gy) provide the most efficient fit to the current dataset. On multivariate analysis V38 (volume of the esophagus that receives 38 Gy or above, 95 %-CI 28.2–57.3) was the most significant predictor of AE ≥ grade 2 (HR = 1.05, CI 1.01–1.09, p = 0.007). Following high-dose accelerated radiotherapy the rate of AE ≥ grade 2 is slightly lower than reported for concomitant radio-chemotherapy with the

  7. Use of a gentamicin-impregnated collagen sheet (Collatamp(®)) in the management of major soft tissue complications in pediatric cochlear implants.

    Science.gov (United States)

    Benito-González, Fernando; Benito, Jose; Sánchez, Luis Alberto Guardado; Estevez Alonso, Santiago; Muñoz Herrera, Angel; Batuecas-Caletrio, Angel

    2014-09-01

    The objective was to report the effectiveness of salvage treatment in soft tissue infection around cochlear implants with an absorbable gentamicin collagen sheet and a periosteum and skin rotation flaps. Three patients with cochlear implant and persistent surrounding soft tissue infection are included. All of them underwent antibiotic treatment prior to surgery without any response. In this study preoperative and postoperative audiograms were practiced. Surgical excision of infectious skin and a periosteum and skin rotation flaps were performed. The cochlear implant was refixed in the temporal bone and a gentamicin-impregnated collagen sheet was located covering the cochlear implant. headings In all patients with soft tissue infection around the cochlear implant, infection was completely resolved. It was not necessary to remove the device in any case. The use of an absorbable gentamicin-impregnated collagen sheet is not described for the management of soft tissue complications in pediatric cochlear implant patients. The local application of high concentrations of antibiotic administered by this sheet may be effective against resistant bacteria and, in conjunction with surgery, may resolve this type of complications.

  8. Planejamento tridimensional para radioterapia de tumores de esôfago: comparação de técnicas de tratamento e análise de probabilidade de complicações Three-dimensional radiotherapy planning system for esophageal tumors: comparison of treatment techniques and analysis of probability of complications

    Directory of Open Access Journals (Sweden)

    Pitágoras Báskara Justino

    2003-06-01

    Full Text Available Para comparar diversas técnicas de irradiação para o câncer de esôfago, foi utilizado sistema de planejamento tridimensional. Em um paciente com carcinoma espinocelular de esôfago médio, foram estudadas as seguintes técnicas de tratamento: dois campos ântero-posteriores e dois campos látero-laterais paralelos e opostos, três campos em "Y" e em "T" e quatro campos em "X". Foram obtidos os histogramas dose-volume, considerando como órgãos de risco medula espinhal e pulmões. Os resultados foram analisados de acordo com as recomendações da Normal Tissue Complication Probability (NTCP e Tumor Control Probability (TCP. Quanto às doses de irradiação em pulmão, a melhor opção foi a técnica em dois campos ântero-posteriores paralelos e opostos. A medula foi mais poupada quando se utilizaram campos látero-laterais. Sugerimos a combinação de pelo menos duas técnicas de tratamento: ântero-posterior e as técnicas com campos em "Y", "T" ou látero-laterais, para o balanceamento das doses em pulmões e medula espinhal. Ou, ainda, a utilização de técnicas de três campos durante todo o tratamento.Radiotherapy techniques for esophageal cancer were compared using a three-dimensional planning system. We studied the following treatment techniques used for a patient with squamous cell carcinoma of the middle third of the esophagus: two antero-posterior and two latero-lateral parallel opposed fields, three fields ("Y" and "T", and four fields ("X". Dose-volume histograms were obtained considering spinal cord and lungs as organs at risk. Analysis was performed comparing doses in these organs as recommended by the Normal Tissue Complication Probability (NTCP and Tumor Control Probability (TCP. When only the lungs were considered the best technique was two antero-posterior parallel opposed fields. The spinal cord was best protected using latero-lateral fields. We suggest the combination of at least two treatment techniques: antero

  9. Postmastectomy Chest Wall Radiation to a Temporary Tissue Expander or Permanent Breast Implant-Is There a Difference in Complication Rates?

    International Nuclear Information System (INIS)

    Anderson, Penny R.; Freedman, Gary; Nicolaou, Nicos; Sharma, Navesh; Li Tianyu; Topham, Neal; Morrow, Monica

    2009-01-01

    Purpose: The purpose of this study was to evaluate the likelihood of complications and cosmetic results among breast cancer patients who underwent modified radical mastectomy (MRM) and breast reconstruction followed by radiation therapy (RT) to either a temporary tissue expander (TTE) or permanent breast implant (PI). Methods and Materials: Records were reviewed of 74 patients with breast cancer who underwent MRM followed by breast reconstruction and RT. Reconstruction consisted of a TTE usually followed by exchange to a PI. RT was delivered to the TTE in 62 patients and to the PI in 12 patients. Dose to the reconstructed chest wall was 50 Gy. Median follow-up was 48 months. The primary end point was the incidence of complications involving the reconstruction. Results: There was no significant difference in the rate of major complications in the PI group (0%) vs. 4.8% in the TTE group. No patients lost the reconstruction in the PI group. Three patients lost the reconstruction in the TTE group. There were excellent/good cosmetic scores in 90% of the TTE group and 80% of the PI group (p = 0.22). On multivariate regression models, the type of reconstruction irradiated had no statistically significant impact on complication rates. Conclusions: Patients treated with breast reconstruction and RT can experience low rates of major complications. We demonstrate no significant difference in the overall rate of major or minor complications between the TTE and PI groups. Postmastectomy RT to either the TTE or the PI should be considered as acceptable treatment options in all eligible patients.

  10. The theoretical benefit of beam fringe compensation and field size reduction for iso-normal tissue complication probability dose escalation in radiotherapy of lung cancer

    NARCIS (Netherlands)

    Engelsman, Martijn; Remeijer, Peter; van Herk, Marcel; Mijnheer, Ben; Damen, Eugène

    2003-01-01

    To assess the benefit of beam fringe (50%-90% dose level) sharpening for lung tumors, we performed a numerical simulation in which all geometrical errors (breathing motion, random and systematic errors) are included. A 50 mm diameter lung tumor, located centrally in a lung-equivalent phantom was

  11. Variation of normal tissue complication probability (NTCP) estimates of radiation-induced hypothyroidism in relation to changes in delineation of the thyroid gland

    DEFF Research Database (Denmark)

    Rønjom, Marianne Feen; Brink, Carsten; Laugaard Lorenzen, Ebbe

    2015-01-01

    volume, Dmean and estimated risk of HT. Bland-Altman plots were used for assessment of the systematic (mean) and random [standard deviation (SD)] variability of the three parameters, and a method for displaying the spatial variation in delineation differences was developed. Results. Intra......-observer variability resulted in a mean difference in thyroid volume and Dmean of 0.4 cm(3) (SD ± 1.6) and -0.5 Gy (SD ± 1.0), respectively, and 0.3 cm(3) (SD ± 1.8) and 0.0 Gy (SD ± 1.3) for inter-observer variability. The corresponding mean differences of NTCP values for radiation-induced HT due to intra- and inter...

  12. The effect of the overall treatment time of fractionated irradiation on the tumor control probability of a human soft tissue sarcoma xenograft in nude mice

    International Nuclear Information System (INIS)

    Allam, Ayman; Perez, Luis A.; Huang, Peigen; Taghian, Alphonse; Azinovic, Ignacio; Freeman, Jill; Duffy, Michael; Efird, Jimmy; Suit, Herman D.

    1995-01-01

    Purpose: To study the impact of the overall treatment time of fractionated irradiation on the tumor control probability (TCP) of a human soft tissue sarcoma xenograft growing in nude mice, as well as to compare the pretreatment potential doubling time (T pot ) of this tumor to the effective doubling time (T eff ) derived from three different schedules of irradiation using the same total number of fractions with different overall treatment times. Methods and Materials: The TCP was assessed using the TCD 50 value (the 50% tumor control dose) as an end point. A total of 240 male nude mice, 7-8 weeks old were used in three experimental groups that received the same total number of fractions (30 fractions) with different overall treatment times. In group 1, the animals received three equal fractions/day for 10 consecutive days, in group 2 they received two equal fractions/day for 15 consecutive days, and in group 3 one fraction/day for 30 consecutive days. All irradiations were given under normal blood flow conditions to air breathing animals. The mean tumor diameter at the start of irradiation was 7-8 mm. The mean interfraction intervals were from 8-24 h. The T pot was measured using Iododeoxyuridine (IudR) labeling and flow cytometry and was compared to T eff . Results: The TCD 50 values of the three different treatment schedules were 58.8 Gy, 63.2 Gy, and 75.6 Gy for groups 1, 2, and 3, respectively. This difference in TCD 50 values was significant (p pot (2.4 days) was longer than the calculated T eff in groups 2 and 3 (1.35 days). Conclusion: Our data show a significant loss in TCP with prolongation of the overall treatment time. This is most probably due to an accelerated repopulation of tumor clonogens. The pretreatment T pot of this tumor model does not reflect the actual doubling of the clonogens in a protracted regimen

  13. SU-E-T-630: Predictive Modeling of Mortality, Tumor Control, and Normal Tissue Complications After Stereotactic Body Radiotherapy for Stage I Non-Small Cell Lung Cancer

    International Nuclear Information System (INIS)

    Lindsay, WD; Berlind, CG; Gee, JC; Simone, CB

    2015-01-01

    Purpose: While rates of local control have been well characterized after stereotactic body radiotherapy (SBRT) for stage I non-small cell lung cancer (NSCLC), less data are available characterizing survival and normal tissue toxicities, and no validated models exist assessing these parameters after SBRT. We evaluate the reliability of various machine learning techniques when applied to radiation oncology datasets to create predictive models of mortality, tumor control, and normal tissue complications. Methods: A dataset of 204 consecutive patients with stage I non-small cell lung cancer (NSCLC) treated with stereotactic body radiotherapy (SBRT) at the University of Pennsylvania between 2009 and 2013 was used to create predictive models of tumor control, normal tissue complications, and mortality in this IRB-approved study. Nearly 200 data fields of detailed patient- and tumor-specific information, radiotherapy dosimetric measurements, and clinical outcomes data were collected. Predictive models were created for local tumor control, 1- and 3-year overall survival, and nodal failure using 60% of the data (leaving the remainder as a test set). After applying feature selection and dimensionality reduction, nonlinear support vector classification was applied to the resulting features. Models were evaluated for accuracy and area under ROC curve on the 81-patient test set. Results: Models for common events in the dataset (such as mortality at one year) had the highest predictive power (AUC = .67, p < 0.05). For rare occurrences such as radiation pneumonitis and local failure (each occurring in less than 10% of patients), too few events were present to create reliable models. Conclusion: Although this study demonstrates the validity of predictive analytics using information extracted from patient medical records and can most reliably predict for survival after SBRT, larger sample sizes are needed to develop predictive models for normal tissue toxicities and more advanced

  14. SU-E-T-630: Predictive Modeling of Mortality, Tumor Control, and Normal Tissue Complications After Stereotactic Body Radiotherapy for Stage I Non-Small Cell Lung Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Lindsay, WD [University of Pennsylvania, Philadelphia, PA (United States); Oncora Medical, LLC, Philadelphia, PA (United States); Berlind, CG [Georgia Institute of Technology, Atlanta, GA (Georgia); Oncora Medical, LLC, Philadelphia, PA (United States); Gee, JC; Simone, CB [University of Pennsylvania, Philadelphia, PA (United States)

    2015-06-15

    Purpose: While rates of local control have been well characterized after stereotactic body radiotherapy (SBRT) for stage I non-small cell lung cancer (NSCLC), less data are available characterizing survival and normal tissue toxicities, and no validated models exist assessing these parameters after SBRT. We evaluate the reliability of various machine learning techniques when applied to radiation oncology datasets to create predictive models of mortality, tumor control, and normal tissue complications. Methods: A dataset of 204 consecutive patients with stage I non-small cell lung cancer (NSCLC) treated with stereotactic body radiotherapy (SBRT) at the University of Pennsylvania between 2009 and 2013 was used to create predictive models of tumor control, normal tissue complications, and mortality in this IRB-approved study. Nearly 200 data fields of detailed patient- and tumor-specific information, radiotherapy dosimetric measurements, and clinical outcomes data were collected. Predictive models were created for local tumor control, 1- and 3-year overall survival, and nodal failure using 60% of the data (leaving the remainder as a test set). After applying feature selection and dimensionality reduction, nonlinear support vector classification was applied to the resulting features. Models were evaluated for accuracy and area under ROC curve on the 81-patient test set. Results: Models for common events in the dataset (such as mortality at one year) had the highest predictive power (AUC = .67, p < 0.05). For rare occurrences such as radiation pneumonitis and local failure (each occurring in less than 10% of patients), too few events were present to create reliable models. Conclusion: Although this study demonstrates the validity of predictive analytics using information extracted from patient medical records and can most reliably predict for survival after SBRT, larger sample sizes are needed to develop predictive models for normal tissue toxicities and more advanced

  15. Comparison of vancomycin and linezolid in patients with peripheral vascular disease and/or diabetes in an observational European study of complicated skin and soft-tissue infections due to methicillin-resistant Staphylococcus aureus.

    Science.gov (United States)

    Eckmann, C; Nathwani, D; Lawson, W; Corman, S; Solem, C; Stephens, J; Macahilig, C; Li, J; Charbonneau, C; Baillon-Plot, N; Haider, S

    2015-09-01

    Suboptimal antibiotic penetration into soft tissues can occur in patients with poor circulation due to peripheral vascular disease (PVD) or diabetes. We conducted a real-world analysis of antibiotic treatment, hospital resource use and clinical outcomes in patients with PVD and/or diabetes receiving linezolid or vancomycin for the treatment of methicillin-resistant Staphylococcus aureus complicated skin and soft-tissue infections (MRSA cSSTIs) across Europe. This subgroup analysis evaluated data obtained from a retrospective, observational medical chart review study that captured patient data from 12 European countries. Data were obtained from the medical records of patients ≥ 18 years of age, hospitalized with an MRSA cSSTI between 1 July 2010 and 30 June 2011 and discharged alive by 31 July 2011. Hospital length of stay and length of treatment were compared between the treatment groups using inverse probability of treatment weights to adjust for clinical and demographic differences. A total of 485 patients had PVD or diabetes and received treatment with either vancomycin (n = 258) or linezolid (n = 227). After adjustment, patients treated with linezolid compared with vancomycin respectively had significantly shorter hospital stays (17.9 ± 13.6 vs. 22.6 ± 13.6 days; p linezolid and vancomycin groups, respectively (p linezolid compared with vancomycin. Copyright © 2015. Published by Elsevier Ltd.

  16. The effect of the overall treatment time of fractionated irradiation on the tumor control probability of a human soft tissue sarcoma xenograft in nude mice

    Energy Technology Data Exchange (ETDEWEB)

    Allam, Ayman; Perez, Luis A; Huang, Peigen; Taghian, Alphonse; Azinovic, Ignacio; Freeman, Jill; Duffy, Michael; Efird, Jimmy; Suit, Herman D

    1995-04-30

    Purpose: To study the impact of the overall treatment time of fractionated irradiation on the tumor control probability (TCP) of a human soft tissue sarcoma xenograft growing in nude mice, as well as to compare the pretreatment potential doubling time (T{sub pot}) of this tumor to the effective doubling time (T{sub eff}) derived from three different schedules of irradiation using the same total number of fractions with different overall treatment times. Methods and Materials: The TCP was assessed using the TCD{sub 50} value (the 50% tumor control dose) as an end point. A total of 240 male nude mice, 7-8 weeks old were used in three experimental groups that received the same total number of fractions (30 fractions) with different overall treatment times. In group 1, the animals received three equal fractions/day for 10 consecutive days, in group 2 they received two equal fractions/day for 15 consecutive days, and in group 3 one fraction/day for 30 consecutive days. All irradiations were given under normal blood flow conditions to air breathing animals. The mean tumor diameter at the start of irradiation was 7-8 mm. The mean interfraction intervals were from 8-24 h. The T{sub pot} was measured using Iododeoxyuridine (IudR) labeling and flow cytometry and was compared to T{sub eff}. Results: The TCD{sub 50} values of the three different treatment schedules were 58.8 Gy, 63.2 Gy, and 75.6 Gy for groups 1, 2, and 3, respectively. This difference in TCD{sub 50} values was significant (p < 0.05) between groups 1 and 2 (30 fractions/10 days and 30 fractions/15 days) vs. group 3 (30 fractions/30 days). The loss in TCP due to the prolongation of the overall treatment time from 10 days to 30 days was found to be 1.35-1.4 Gy/day. The pretreatment T{sub pot} (2.4 days) was longer than the calculated T{sub eff} in groups 2 and 3 (1.35 days). Conclusion: Our data show a significant loss in TCP with prolongation of the overall treatment time. This is most probably due to an

  17. Ruin probabilities

    DEFF Research Database (Denmark)

    Asmussen, Søren; Albrecher, Hansjörg

    The book gives a comprehensive treatment of the classical and modern ruin probability theory. Some of the topics are Lundberg's inequality, the Cramér-Lundberg approximation, exact solutions, other approximations (e.g., for heavy-tailed claim size distributions), finite horizon ruin probabilities......, extensions of the classical compound Poisson model to allow for reserve-dependent premiums, Markov-modulation, periodicity, change of measure techniques, phase-type distributions as a computational vehicle and the connection to other applied probability areas, like queueing theory. In this substantially...... updated and extended second version, new topics include stochastic control, fluctuation theory for Levy processes, Gerber–Shiu functions and dependence....

  18. Comparison of Dose Response Models for Predicting Normal Tissue Complications from Cancer Radiotherapy: Application in Rat Spinal Cord

    Energy Technology Data Exchange (ETDEWEB)

    Adamus-Górka, Magdalena; Mavroidis, Panayiotis, E-mail: panayiotis.mavroidis@ki.se; Lind, Bengt K.; Brahme, Anders [Department of Medical Radiation Physics, Karolinska Institutet and Stockholm University, Stockholm S-17176 (Sweden)

    2011-05-18

    Seven different radiobiological dose-response models have been compared with regard to their ability to describe experimental data. The first four models, namely the critical volume, the relative seriality, the inverse tumor and the critical element models are mainly based on cell survival biology. The other three models: the Lyman (Gaussian distribution), the parallel architecture and the Weibull distribution models are semi-empirical and rather based on statistical distributions. The maximum likelihood estimation was used to fit the models to experimental data and the χ{sup 2}-distribution, AIC criterion and F-test were applied to compare the goodness-of-fit of the models. The comparison was performed using experimental data for rat spinal cord injury. Both the shape of the dose-response curve and the ability of handling the volume dependence were separately compared for each model. All the models were found to be acceptable in describing the present experimental dataset (p > 0.05). For the white matter necrosis dataset, the Weibull and Lyman models were clearly superior to the other models, whereas for the vascular damage case, the Relative Seriality model seems to have the best performance although the Critical volume, Inverse tumor, Critical element and Parallel architecture models gave similar results. Although the differences between many of the investigated models are rather small, they still may be of importance in indicating the advantages and limitations of each particular model. It appears that most of the models have favorable properties for describing dose-response data, which indicates that they may be suitable to be used in biologically optimized intensity modulated radiation therapy planning, provided a proper estimation of their radiobiological parameters had been performed for every tissue and clinical endpoint.

  19. Comparison of Dose Response Models for Predicting Normal Tissue Complications from Cancer Radiotherapy: Application in Rat Spinal Cord

    International Nuclear Information System (INIS)

    Adamus-Górka, Magdalena; Mavroidis, Panayiotis; Lind, Bengt K.; Brahme, Anders

    2011-01-01

    Seven different radiobiological dose-response models have been compared with regard to their ability to describe experimental data. The first four models, namely the critical volume, the relative seriality, the inverse tumor and the critical element models are mainly based on cell survival biology. The other three models: the Lyman (Gaussian distribution), the parallel architecture and the Weibull distribution models are semi-empirical and rather based on statistical distributions. The maximum likelihood estimation was used to fit the models to experimental data and the χ 2 -distribution, AIC criterion and F-test were applied to compare the goodness-of-fit of the models. The comparison was performed using experimental data for rat spinal cord injury. Both the shape of the dose-response curve and the ability of handling the volume dependence were separately compared for each model. All the models were found to be acceptable in describing the present experimental dataset (p > 0.05). For the white matter necrosis dataset, the Weibull and Lyman models were clearly superior to the other models, whereas for the vascular damage case, the Relative Seriality model seems to have the best performance although the Critical volume, Inverse tumor, Critical element and Parallel architecture models gave similar results. Although the differences between many of the investigated models are rather small, they still may be of importance in indicating the advantages and limitations of each particular model. It appears that most of the models have favorable properties for describing dose-response data, which indicates that they may be suitable to be used in biologically optimized intensity modulated radiation therapy planning, provided a proper estimation of their radiobiological parameters had been performed for every tissue and clinical endpoint

  20. High-density lipoprotein-based therapy reduces the hemorrhagic complications associated with tissue plasminogen activator treatment in experimental stroke.

    Science.gov (United States)

    Lapergue, Bertrand; Dang, Bao Quoc; Desilles, Jean-Philippe; Ortiz-Munoz, Guadalupe; Delbosc, Sandrine; Loyau, Stéphane; Louedec, Liliane; Couraud, Pierre-Olivier; Mazighi, Mikael; Michel, Jean-Baptiste; Meilhac, Olivier; Amarenco, Pierre

    2013-03-01

    We have previously reported that intravenous injection of high-density lipoproteins (HDLs) was neuroprotective in an embolic stroke model. We hypothesized that HDL vasculoprotective actions on the blood-brain barrier (BBB) may decrease hemorrhagic transformation-associated with tissue plasminogen activator (tPA) administration in acute stroke. We used tPA alone or in combination with HDLs in vivo in 2 models of focal middle cerebral artery occlusion (MCAO) (embolic and 4-hour monofilament MCAO) and in vitro in a model of BBB. Sprague-Dawley rats were submitted to MCAO, n=12 per group. The rats were then randomly injected with tPA (10 mg/kg) or saline with or without human plasma purified-HDL (10 mg/kg). The therapeutic effects of HDL and BBB integrity were assessed blindly 24 hours later. The integrity of the BBB was also tested using an in vitro model of human cerebral endothelial cells under oxygen-glucose deprivation. tPA-treated groups had significantly higher mortality and rate of hemorrhagic transformation at 24 hours in both MCAO models. Cotreatment with HDL significantly reduced stroke-induced mortality versus tPA alone (by 42% in filament MCAO, P=0.009; by 73% in embolic MCAO, P=0.05) and tPA-induced intracerebral parenchymal hematoma (by 92% in filament MCAO, by 100% in embolic MCAO; Phemorrhagic transformation in rat models of MCAO. Both in vivo and in vitro results support the vasculoprotective action of HDLs on BBB under ischemic conditions.

  1. Generalized Probability-Probability Plots

    NARCIS (Netherlands)

    Mushkudiani, N.A.; Einmahl, J.H.J.

    2004-01-01

    We introduce generalized Probability-Probability (P-P) plots in order to study the one-sample goodness-of-fit problem and the two-sample problem, for real valued data.These plots, that are constructed by indexing with the class of closed intervals, globally preserve the properties of classical P-P

  2. Probability-1

    CERN Document Server

    Shiryaev, Albert N

    2016-01-01

    This book contains a systematic treatment of probability from the ground up, starting with intuitive ideas and gradually developing more sophisticated subjects, such as random walks, martingales, Markov chains, the measure-theoretic foundations of probability theory, weak convergence of probability measures, and the central limit theorem. Many examples are discussed in detail, and there are a large number of exercises. The book is accessible to advanced undergraduates and can be used as a text for independent study. To accommodate the greatly expanded material in the third edition of Probability, the book is now divided into two volumes. This first volume contains updated references and substantial revisions of the first three chapters of the second edition. In particular, new material has been added on generating functions, the inclusion-exclusion principle, theorems on monotonic classes (relying on a detailed treatment of “π-λ” systems), and the fundamental theorems of mathematical statistics.

  3. Ignition Probability

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — USFS, State Forestry, BLM, and DOI fire occurrence point locations from 1987 to 2008 were combined and converted into a fire occurrence probability or density grid...

  4. Tissue

    Directory of Open Access Journals (Sweden)

    David Morrissey

    2012-01-01

    Full Text Available Purpose. In vivo gene therapy directed at tissues of mesenchymal origin could potentially augment healing. We aimed to assess the duration and magnitude of transene expression in vivo in mice and ex vivo in human tissues. Methods. Using bioluminescence imaging, plasmid and adenoviral vector-based transgene expression in murine quadriceps in vivo was examined. Temporal control was assessed using a doxycycline-inducible system. An ex vivo model was developed and optimised using murine tissue, and applied in ex vivo human tissue. Results. In vivo plasmid-based transgene expression did not silence in murine muscle, unlike in liver. Although maximum luciferase expression was higher in muscle with adenoviral delivery compared with plasmid, expression reduced over time. The inducible promoter cassette successfully regulated gene expression with maximum levels a factor of 11 greater than baseline. Expression was re-induced to a similar level on a temporal basis. Luciferase expression was readily detected ex vivo in human muscle and tendon. Conclusions. Plasmid constructs resulted in long-term in vivo gene expression in skeletal muscle, in a controllable fashion utilising an inducible promoter in combination with oral agents. Successful plasmid gene transfection in human ex vivo mesenchymal tissue was demonstrated for the first time.

  5. Tigecycline Susceptibility Trends Among Pathogens Isolated from Complicated Skin and Soft-Tissue Infections in North and Latin America: 2012–2016

    Science.gov (United States)

    Hoban, Daryl; Renteria, Martha; Leister-Tebbe, Heidi; Sahm, Dan

    2017-01-01

    Abstract Background The Tigecycline Evaluation Surveillance Trial (TEST) monitors the activity of tigecycline and other antimicrobials against clinically-relevant pathogens collected globally. This study reports the activity of tigecycline (TGC) against Gram-positive and Gram-negative isolates collected in North and Latin America from patients with complicated skin and soft-tissue infections (CSSTI). Methods Hospital sites from North America (NA) and Latin America (LA) collected non-duplicate clinical Gram-positive and -negative isolates from various complicated skin and skin structure infection sources during 2012–2016. Organism identification and antibiotic susceptibility (S) testing was performed by the local laboratories. Susceptibility testing was determined using the broth microdilution method according to CLSI guidelines and categorical interpretation of results was done using CLSI or FDA (tigecycline) breakpoint criteria where appropriate. Cefoxitin disk testing was performed for all S. aureus to determine methicillin susceptibility (i.e., MRSA and MSSA). Results The table provides %S and MIC90 data for TGC against CSSTI isolates Region, n, %S, MIC 90 (µg/ml) North America Latin America Organism n %S MIC 90 n %S MIC 90 S. aureus 2270 100 0.12 310 100 0.25 Enterobacter spp. 925 96.4 1 159 92.5 2 P. aeruginosa 758 na* > 8 165 na > 8 E. coli 716 99.9 0.25 241 100 0.25 Enterococcus spp. 691 99.3 0.12 135 100 0.12 S. agalactiae 503 100 0.12 58 100 0.06 K. pneumoniae 471 94.9 2 152 91.5 2 S. marcescens 347 96.8 2 67 97.0 2 A. baumannii 310 na* 2 97 na 1 K. oxytoca 204 99.0 0.5 15 100 1 *na = not applicable or no breakpoints available for this species. Conclusion Based on %S and MIC90 data TGC exhibited potent activity against isolates of all organism groups from complicated skin and soft-tissue infections, regardless of the geographic region. However, given the potential many of these organisms have for developing resistance, continued and careful

  6. Study on the plasma leptin level and leptin mRNA expression in cancerous breast tissue in patients with breast carcinoma complicated with obesity

    International Nuclear Information System (INIS)

    Li Chunrui; Liu Wenli; Sun Hanying; Zhou Jianfeng

    2006-01-01

    Objective: To study the plasma leptin level and leptin mRNA expression in cancerous breast tissue in patients with breast cancer complicated with obesity. Methods: Plasma leptin levels were measured with RIA in 48 breast cancer patients with obesity, 36 patients with various benign breast disorders and obesity and 40 controls (with simple obesity only). The leptin mRNA expression in the surgical specimens from the 84 patients with breast disease was also examined with RT-PCR, Results: The plasma leptin levels in the breast cancer patients (12.02 ± 1.23 μg/L) were significantly higher than those in patients with benign breast disorders (9.84 ± 0.98 μg/L) and controls (9.79 ± 1.16 μg/L) (both P<0.05). The expression levels of leptin mRNA in specimens from malignant breast disease (0.71 ± 0.32), were significantly higher than those in specimens from benign breast diseases (0.41 ± 0.26) (P<0.05), The plasma leptin levels and the tissue leptin mRNA expression levels were mutually positively correlated (r=0.4220 ,P 0.0180). These levels were not correlated with the presence of axillary metastasis, TMN stage, menstrual status, pathological classification and other parameters. Conclusion: Leptin might be a promotive factor in the development of breast cancer. (authors)

  7. Quantum Probabilities as Behavioral Probabilities

    Directory of Open Access Journals (Sweden)

    Vyacheslav I. Yukalov

    2017-03-01

    Full Text Available We demonstrate that behavioral probabilities of human decision makers share many common features with quantum probabilities. This does not imply that humans are some quantum objects, but just shows that the mathematics of quantum theory is applicable to the description of human decision making. The applicability of quantum rules for describing decision making is connected with the nontrivial process of making decisions in the case of composite prospects under uncertainty. Such a process involves deliberations of a decision maker when making a choice. In addition to the evaluation of the utilities of considered prospects, real decision makers also appreciate their respective attractiveness. Therefore, human choice is not based solely on the utility of prospects, but includes the necessity of resolving the utility-attraction duality. In order to justify that human consciousness really functions similarly to the rules of quantum theory, we develop an approach defining human behavioral probabilities as the probabilities determined by quantum rules. We show that quantum behavioral probabilities of humans do not merely explain qualitatively how human decisions are made, but they predict quantitative values of the behavioral probabilities. Analyzing a large set of empirical data, we find good quantitative agreement between theoretical predictions and observed experimental data.

  8. Probability tales

    CERN Document Server

    Grinstead, Charles M; Snell, J Laurie

    2011-01-01

    This book explores four real-world topics through the lens of probability theory. It can be used to supplement a standard text in probability or statistics. Most elementary textbooks present the basic theory and then illustrate the ideas with some neatly packaged examples. Here the authors assume that the reader has seen, or is learning, the basic theory from another book and concentrate in some depth on the following topics: streaks, the stock market, lotteries, and fingerprints. This extended format allows the authors to present multiple approaches to problems and to pursue promising side discussions in ways that would not be possible in a book constrained to cover a fixed set of topics. To keep the main narrative accessible, the authors have placed the more technical mathematical details in appendices. The appendices can be understood by someone who has taken one or two semesters of calculus.

  9. A prospective, multicenter, observational study of complicated skin and soft tissue infections in hospitalized patients: clinical characteristics, medical treatment, and outcomes

    Directory of Open Access Journals (Sweden)

    Lipsky Benjamin A

    2012-09-01

    Full Text Available Abstract Background Complicated skin and soft tissue infections (cSSTIs occur frequently, but limited data do not allow any consensus on an optimal treatment strategy. We designed this prospective, multicenter, observational study to to explore the current epidemiology, treatment, and resulting clinical outcomes of cSSTIs to help develop strategies to potentially improve outcomes. Methods From June 2008 to December 2009 we enrolled a pre-specified number of adults treated in 56 U.S. hospitals with intravenous antibiotic(s for any of the following cSSTIs: diabetic foot infection (DFI; surgical site infection (SSI; deep soft tissue abscess (DSTA; or, cellulitis. Investigators treated all patients per their usual practice during the study and collected data on a standardized form. Results We enrolled 1,033 patients (DFI 27%; SSI 32%; DSTA 14%; cellulitis 27%; mean age 54 years; 54% male, of which 74% had healthcare-associated risk factors. At presentation, 89% of patients received initial empiric therapy with intravenous antibiotics; ~20% of these patients had this empiric regimen changed or discontinued based on culture and sensitivity results. Vancomycin was the most frequently used initial intravenous antibiotic, ordered in 61% of cases. During their stay 44% of patients underwent a surgical procedure related to the study infection, usually incision and drainage or debridement. The mean length of stay was 7.1 days, ranging from 5.8 (DSTA to 8.1 (SSI. Conclusion Our findings from this large prospective observational study that characterized patients with cSSTIs from diverse US inpatient populations provide useful information on the current epidemiology, clinical management practices and outcomes of this common infection.

  10. Interstitial brachytherapy for stage I and II squamous cell carcinoma of the oral tongue: factors influencing local control and soft tissue complications

    International Nuclear Information System (INIS)

    Fujita, Minoru; Hirokawa, Yutaka; Kashiwado, Kouzo; Akagi, Yukio; Kashimoto, Kazuki; Kiriu, Hiroshi; Matsuura, Kanji; Ito, Katsuhide

    1999-01-01

    Purpose: Our aim was to study the treatment parameters that influence local control and soft tissue complications (STC) in a series of 207 Stage I and II squamous cell carcinomas of the oral tongue treated by interstitial brachytherapy (BRT) alone (127 patients), or by a combination using external beam irradiation (EBI) (80 patients) between 1980 and 1993. Methods and Materials: The patient distribution was 93 T1, 72 T2a, and 42 T2b. The prescribed BRT dose at the plane 5 mm from the plane of the radioactive sources was 65-70 Gy in BRT alone, and 50-60 Gy in the combined treatment using EBI. Generally, an EBI dose of 30 Gy was used. No prophylactic neck treatment was performed. Results: The 5-year local recurrence-free rate for T1, T2a, and T2b was 92.9%, 81.9%, and 71.8%, respectively (p 85 Gy (p = 0.01), BRT dose > 55 Gy (p = 0.04), and a dose rate = 0.6 Gy/h was significantly related to more STC in BRT alone (p = 0.03), and that a dose rate > = 0.55 Gy/h (p 70 Gy (p 100 Gy (p 85 Gy and 55 Gy and < = 70 Gy, and < 0.55 Gy/h, respectively. We also recommend longer follow-up periods; more than 5 years might be necessary for late local recurrences and for secondary cancers

  11. Safety and tolerability of tigecycline for the treatment of complicated skin and soft-tissue and intra-abdominal infections: an analysis based on five European observational studies.

    Science.gov (United States)

    Guirao, Xavier; Sánchez García, Miguel; Bassetti, Matteo; Bodmann, Klaus Friedrich; Dupont, Hervé; Montravers, Philippe; Heizmann, Wolfgang R; Capparella, Maria Rita; Simoneau, Damien; Eckmann, Christian

    2013-07-01

    Tigecycline is approved for the treatment of complicated skin and soft-tissue infections (cSSTIs) and complicated intra-abdominal infections (cIAIs) in adults. In this analysis the safety and tolerability profile of tigecycline (used alone or in combination) for the treatment of patients with approved indications of cSSTI and cIAI were examined under real-life clinical conditions. Individual patient-level data were pooled from five European observational studies (July 2006 to October 2011). A total of 254 cSSTI and 785 cIAI patients were included. The mean age was 63 years; 34.4% and 56.6% were in intensive care units, 90.9% and 88.1% had at least one comorbidity and mean Acute Physiology and Chronic Health Evaluation (APACHE) II scores at the beginning of treatment were 15.0 ± 7.9 and 16.9 ± 7.6, respectively. Data on adverse events (AEs) were available for 198 cSSTI and 590 cIAI patients in three studies. Nausea and vomiting were reported in ≤ 2% of patients. The most common serious AEs were multi-organ failure (4.0% and 10.0% in cSSTI and cIAI patients, respectively) and sepsis (4.0% and 6.1%, respectively). Death was recorded for 24/254 (9.4%) cSSTI and 147/785 (18.7%) cIAI patients. Mortality rates were higher in the group with a baseline APACHE II score of >15 compared with those with a score of ≤ 15 (18.7% versus 3.5% for cSSTI patients and 23.8% versus 16.0% for cIAI patients). A similar trend was seen when cIAI patients were stratified by Sequential Organ Failure Assessment (SOFA) score. The safety and tolerability of tigecycline, alone and in combination, are consistent with the level of critical illness among patients in these real-life studies.

  12. Four patients with Sillence type I osteogenesis imperfecta and mild bone fragility, complicated by left ventricular cardiac valvular disease and cardiac tissue fragility caused by type I collagen mutations

    DEFF Research Database (Denmark)

    Vandersteen, Anthony M; Lund, Allan M; Ferguson, David J P

    2014-01-01

    Osteogenesis imperfecta (OI) type I is a hereditary disorder of connective tissue (HDCT) characterized by blue or gray sclerae, variable short stature, dentinogenesis imperfecta, hearing loss, and recurrent fractures from infancy. We present four examples of OI type I complicated by valvular heart...

  13. Converting dose distributions into tumour control probability

    International Nuclear Information System (INIS)

    Nahum, A.E.

    1996-01-01

    The endpoints in radiotherapy that are truly of relevance are not dose distributions but the probability of local control, sometimes known as the Tumour Control Probability (TCP) and the Probability of Normal Tissue Complications (NTCP). A model for the estimation of TCP based on simple radiobiological considerations is described. It is shown that incorporation of inter-patient heterogeneity into the radiosensitivity parameter a through s a can result in a clinically realistic slope for the dose-response curve. The model is applied to inhomogeneous target dose distributions in order to demonstrate the relationship between dose uniformity and s a . The consequences of varying clonogenic density are also explored. Finally the model is applied to the target-volume DVHs for patients in a clinical trial of conformal pelvic radiotherapy; the effect of dose inhomogeneities on distributions of TCP are shown as well as the potential benefits of customizing the target dose according to normal-tissue DVHs. (author). 37 refs, 9 figs

  14. Converting dose distributions into tumour control probability

    Energy Technology Data Exchange (ETDEWEB)

    Nahum, A E [The Royal Marsden Hospital, London (United Kingdom). Joint Dept. of Physics

    1996-08-01

    The endpoints in radiotherapy that are truly of relevance are not dose distributions but the probability of local control, sometimes known as the Tumour Control Probability (TCP) and the Probability of Normal Tissue Complications (NTCP). A model for the estimation of TCP based on simple radiobiological considerations is described. It is shown that incorporation of inter-patient heterogeneity into the radiosensitivity parameter a through s{sub a} can result in a clinically realistic slope for the dose-response curve. The model is applied to inhomogeneous target dose distributions in order to demonstrate the relationship between dose uniformity and s{sub a}. The consequences of varying clonogenic density are also explored. Finally the model is applied to the target-volume DVHs for patients in a clinical trial of conformal pelvic radiotherapy; the effect of dose inhomogeneities on distributions of TCP are shown as well as the potential benefits of customizing the target dose according to normal-tissue DVHs. (author). 37 refs, 9 figs.

  15. Antibacterial Treatment of Meticillin-Resistant Staphylococcus Aureus Complicated Skin and Soft Tissue Infections: a Cost and Budget Impact Analysis in Greek Hospitals.

    Science.gov (United States)

    Athanasakis, Kostas; Petrakis, Ioannis; Ollandezos, Mark; Tsoulas, Christos; Patel, Dipen A; Karampli, Eleftheria; Kyriopoulos, John

    2014-12-01

    Meticillin-resistant staphylococcus aureus (MRSA) is an important cause of antimicrobial-resistant infections worldwide. Its prevalence remains high in the Greek hospital setting. Complicated skin and soft tissue infections (cSSTIs) due to MRSA are associated with prolonged hospitalization, additional healthcare costs and significant morbidity. The purpose of this study was to conduct a cost analysis and a budget impact analysis relative to different management scenarios for MRSA-cSSTIs from a hospital perspective. Equal efficacy was assumed for the pharmacotherapies under evaluation and resource use was elicited via an expert panel of seven local infectious disease specialists. The model was based on a previously published economic model that was adapted for the Greek hospital setting and included a decision tree for the management of hospitalized patients with MRSA-cSSTIs, which simulated costs and outcomes for the duration of hospitalization according to the therapeutic scenario. Inpatient costs consisted of hospitalization, diagnostic/laboratory testing, physician visits and antibiotic treatment. Current economic impact of MRSA-cSSTIs for the inpatient setting in Greek hospitals was estimated at €29,196,218. Total per patient cost according to first-line agent was €2,457, €2,762, €2,850, €3,494 and €3,094 and mean length of stay was 9.2, 12.5, 10.3, 13.0 and 14.0 days for linezolid, vancomycin, daptomycin, tigecycline, and teicoplanin, respectively. An estimated 10,287 MRSA-cSSTI patients are treated annually in Greek hospitals. Thus, increasing the use of linezolid by 11% over a 3-year period (current use 19%; 3 year projection 30%), for the management of MRSA-cSSTIs, could result in 3-year savings of €896,065. Management of MRSA-cSSTI requires intensive resource use; overall healthcare costs differ according to the chosen first-line treatment. In light of considerable budget constraints, development of hospital strategies which facilitate

  16. Mesh complications and failure rates after transvaginal mesh repair compared with abdominal or laparoscopic sacrocolpopexy and to native tissue repair in treating apical prolapse.

    Science.gov (United States)

    Dandolu, Vani; Akiyama, Megumi; Allenback, Gayle; Pathak, Prathamesh

    2017-02-01

    Our objective was to quantitate the extent of complications and failure rate for apical prolapse repair with transvaginal mesh (TVM) use versus sacrocolpopexy over a minimum of 2 years of follow-up. Truven CCAE and Medicare Supplemental databases 2008-2013 were used for analysis. Patients with apical prolapse repair via transvaginal mesh (TVMR), abdominal sacrocolpopexy (ASCP), laparoscopic sacrocolpopexy (LSCP), or native tissue repair (NTR) and continuously enrolled for years were in the study cohort. Surgical failures were identified by reoperation for any prolapse or subsequent use of pessary. SAS® 9.3 was used for analysis. Mesh removal/revision was reported highest in TVMR (5.1 %), followed by LSCP (1.7 %) and ASCP (1.2 %). In those with concomitant sling, combined rates for mesh/sling revision were high, at 9.0 % in TVMR + sling, 5.6 % in ASCP + sling, and 4.5 % LSCP + sling. Sling-alone cases reported a 3.5 % revision rate. Pelvic pain (16.4-22.7 %) and dyspareunia (5.6-7.5 %) were high in all three approaches for apical prolapse repairs. Reoperation for apical prolapse was more common for TVMR (2.9 %) compared with NTR (2.3 %) [odds ratio (OR) 1.27; confidence interval (CI) 1.1-1.47; p 0.002]. Both ASCP and LSCP were superior to NTR (ASCP 1.5 %, OR 0.63, CI 0.46-0.86; p 0.003) and LSCP 1.8 % (OR 0.79, CI 0.62-1.01; p 0.07). Overall prolapse recurrence, as indicated by any compartment surgery for prolapse and/or pessary use, was also noted highest in TVMR (5.9 % OR 1.23, CI 1.11-1.36; p mesh is used for repair, mesh revision is highest with TVMR and lowest with ASCP.

  17. Incidence of delayed complications following percutaneous CT-guided biopsy of bone and soft tissue lesions of the spine and extremities: A 2-year prospective study and analysis of risk factors

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Ambrose J.; Rosenthal, Daniel I. [Massachusetts General Hospital, Boston, MA (United States); Halpern, Elkan F. [Massachusetts General Hospital, Institute of Technology Assessment, Boston, MA (United States)

    2013-01-15

    To prospectively evaluate the incidence of delayed complications (bleeding, pain, infection) following CT-guided biopsies of bone or soft tissue lesions and to identify risk factors that predispose to their occurrence. All adults presenting for CT-guided biopsy of a bone or soft tissue lesion were eligible for the study. Risk factors considered included patient gender and age, bone versus soft tissue, lesion location, lesion depth, anticoagulation, conscious sedation, coaxial biopsy technique, bleeding during the biopsy, dressing type and duration of placement, final diagnosis, needle gauge, number of passes, and number of days to follow-up. Outcomes measured included fever, pain, bruising/hematoma formation, and swelling and were collected by a follow-up phone call within 14 days of the biopsy. Fisher's exact test, the Wald Chi-square test, and univariate, multivariate, and stepwise logistic regression were performed to evaluate the influence of the risk factors on the outcomes. A total of 386 patients participated in the study. The rates of post-biopsy fever, pain, bruising, and swelling were 1.0, 16.1, 15.6, and 9.6 %, respectively. Anticoagulants were identified as a risk factor for fever. Increasing patient age was identified as a risk factor for pain. Female gender and lesion location were identified as risk factors for bruising. Increasing patient age and lesion location were identified as risk factors for swelling. Patient age, female gender, and lesion location are risk factors for delayed minor complications following CT-guided biopsy of a bone or soft tissue lesion. There were no major complications. None of the complications in this series altered patient management. (orig.)

  18. Incidence of delayed complications following percutaneous CT-guided biopsy of bone and soft tissue lesions of the spine and extremities: A 2-year prospective study and analysis of risk factors

    International Nuclear Information System (INIS)

    Huang, Ambrose J.; Rosenthal, Daniel I.; Halpern, Elkan F.

    2013-01-01

    To prospectively evaluate the incidence of delayed complications (bleeding, pain, infection) following CT-guided biopsies of bone or soft tissue lesions and to identify risk factors that predispose to their occurrence. All adults presenting for CT-guided biopsy of a bone or soft tissue lesion were eligible for the study. Risk factors considered included patient gender and age, bone versus soft tissue, lesion location, lesion depth, anticoagulation, conscious sedation, coaxial biopsy technique, bleeding during the biopsy, dressing type and duration of placement, final diagnosis, needle gauge, number of passes, and number of days to follow-up. Outcomes measured included fever, pain, bruising/hematoma formation, and swelling and were collected by a follow-up phone call within 14 days of the biopsy. Fisher's exact test, the Wald Chi-square test, and univariate, multivariate, and stepwise logistic regression were performed to evaluate the influence of the risk factors on the outcomes. A total of 386 patients participated in the study. The rates of post-biopsy fever, pain, bruising, and swelling were 1.0, 16.1, 15.6, and 9.6 %, respectively. Anticoagulants were identified as a risk factor for fever. Increasing patient age was identified as a risk factor for pain. Female gender and lesion location were identified as risk factors for bruising. Increasing patient age and lesion location were identified as risk factors for swelling. Patient age, female gender, and lesion location are risk factors for delayed minor complications following CT-guided biopsy of a bone or soft tissue lesion. There were no major complications. None of the complications in this series altered patient management. (orig.)

  19. Treatment patterns, resource utilization, and outcomes among hospitalized patients with methicillin-resistant Staphylococcus aureus complicated skin and soft tissue infections in Lebanon and Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Matar MJ

    2017-02-01

    Full Text Available Madonna J Matar,1 Rima Moghnieh,2 Adel F Alothman,3 Abdulhakeem O Althaqafi,4 Thamer H Alenazi,3 Fayssal M Farahat,4 Shelby Corman,5 Caitlyn T Solem,5 Nirvana Raghubir,6 Cynthia Macahilig,7 Seema Haider,8 Jennifer M Stephens5 1Department of Infectious Diseases, Notre Dame des Secours University Hospital, Jbeil, Lebanon; 2Department of Internal Medicine, Makassed General Hospital, Beirut, Lebanon; 3College of Medicine, King Saud bin Abdulaziz University for Health Sciences, King Abdullah International Medical Research Center, Riyadh, Saudi Arabia; 4King Abdullah International Medical Research Center, Infection Prevention and Control, King AbdulAziz Medical City, King Saud bin AbdulAziz University for Health Sciences, Jeddah, Saudi Arabia; 5Pharmerit International, Real-World Evidence/Data Analytics, Bethesda, MD, 6Pfizer, New York, NY, 7Medical Data Analytics, Parsippany, NJ, 8Pfizer, Groton, CT, USA Objectives: To describe treatment patterns and medical resource use for methicillin-resistant Staphylococcus aureus (MRSA complicated skin and soft tissue infections (cSSTI in Saudi Arabia and Lebanon in terms of drug selection against the infecting pathogen as well as hospital resource utilization and clinical outcomes among patients with these infections. Methods: This retrospective chart review study evaluated 2011–2012 data from five hospitals in Saudi Arabia and Lebanon. Patients were included if they had been discharged with a diagnosis of MRSA cSSTI, which was culture-proven or suspected based on clinical criteria. Hospital data were abstracted for a random sample of patients with each infection type to capture demographics, treatment patterns, hospital resource utilization, and clinical outcomes. Statistical analysis was descriptive. Results: Data were abstracted from medical records of 87 patients with MRSA cSSTI; mean age 52.4±25.9 years and 61% male. Only 64% of patients received an MRSA active initial therapy, with 56% of first

  20. Probability Aggregates in Probability Answer Set Programming

    OpenAIRE

    Saad, Emad

    2013-01-01

    Probability answer set programming is a declarative programming that has been shown effective for representing and reasoning about a variety of probability reasoning tasks. However, the lack of probability aggregates, e.g. {\\em expected values}, in the language of disjunctive hybrid probability logic programs (DHPP) disallows the natural and concise representation of many interesting problems. In this paper, we extend DHPP to allow arbitrary probability aggregates. We introduce two types of p...

  1. Extraintestinal Complications: Kidney Disorders

    Science.gov (United States)

    ... the ureters, bladder, and urethra for the passage, storage, and voiding of urine. Serious kidney complications associated with IBD are rare, ... Proteinuria, an elevated level of protein in the urine, is one sign of amyloidosis. A biopsy (tissue sample) of the kidney can confirm the diagnosis. Various ...

  2. Complications in ankle arthroscopy

    NARCIS (Netherlands)

    Zengerink, Maartje; van Dijk, C. Niek

    2012-01-01

    To determine the complication rate for ankle arthroscopy. A review of a consecutive series of patients undergoing ankle arthroscopy in our hospital between 1987 and 2006 was undertaken. Anterior ankle arthroscopy was performed by means of a 2-portal dorsiflexion method with intermittent soft tissue

  3. An integrated logistic formula for prediction of complications from radiosurgery

    International Nuclear Information System (INIS)

    Flickinger, J.C.

    1989-01-01

    An integrated logistic model for predicting the probability of complications when small volumes of tissue receive an inhomogeneous radiation dose is described. This model can be used with either an exponential or linear quadratic correction for dose per fraction and time. Both the exponential and linear quadratic versions of this integrated logistic formula provide reasonable estimates of the tolerance of brain to radiosurgical dose distributions where there are small volumes of brain receiving high radiation doses and larger volumes receiving lower doses. This makes it possible to predict the probability of complications from stereotactic radiosurgery, as well as combinations of fractionated large volume irradiation with a radiosurgical boost. Complication probabilities predicted for single fraction radiosurgery with the Leksell Gamma Unit using 4, 8, 14, and 18 mm diameter collimators as well as for whole brain irradiation combined with a radiosurgical boost are presented. The exponential and linear quadratic versions of the integrated logistic formula provide useful methods of calculating the probability of complications from radiosurgical treatment

  4. Postpartum complications

    International Nuclear Information System (INIS)

    Kronthal, A.J.; Kuhlman, J.E.; Fishman, E.K.

    1990-01-01

    This paper reports the CT findings of major postpartum complications and determine what role CT plays in their evaluation. The CT scans of nine patients with major postpartum complications were retrospectively reviewed. Patients had been referred to CT for evaluation of postpartum fever, abdominal pain, and elevated results of liver function tests. Complications identified at CT included hepatic infarctions (n = 2), endometritis (n = 2), postoperative wound abscess (n = 1), massive abdominal hemorrhage (n = 1), septic thrombophlebitis (n = 1), and renal vein thrombosis (n = 1). CT findings of hepatic infarction included wedge-shaped areas of decreased enhancement conforming to a vascular distribution

  5. Comparison of incidences of normal tissue complications with tumor response in a phase III trial comparing heat plus radiation to radiation alone

    International Nuclear Information System (INIS)

    Dewhirst, M.W.; Sim, D.A.; Grochowski, K.J.

    1984-01-01

    The success of hyperthermia (/sup Δ/) as an adjuvant to radiation (XRT) will depend on whether the increase in tumor control is greater than that for normal tissue reactions. One hundred and thirty dogs and cats were stratified by histology and randomized to receive XRT (460 rads per fraction, two fractions per week, for eight fractions) or /sup Δ/ + XRT (30 min. at 44 +-2 0 C; one fraction per week, four fractions; immediately prior to XRT). Heat induced changes in tumor and normal tissue responses were made by comparing ratios of incidence for /sup Δ/ + XRT and XRT alone (TRR; Thermal Relative Risk). Change in tumor response duration was calculated from statistical analysis of response duration curves (RRR; Relative Relapse Rate). Heat increased early normal tissue reactions (moist desquamation and mucositis by a factor of 1.08. Tumor complete response, by comparison, was significantly improved (TRR = 2.12, p < .001). Late skin fibrosis was also increased (TRR = 1.51), but the prolongation in tumor response was greater (RRR 1.85). The degree of thermal enhancement for all tissues was dependent on the minimum temperature achieved on the first treatment, but the values for tumor were consistently greater than those achieved for normal tissues

  6. Prognosis of complicated clinical course of varicose veins of lower extremities on the basis of analysis of phenotypic characteristics of connective tissue dysplasia

    Directory of Open Access Journals (Sweden)

    Tsarev О.А.

    2015-12-01

    Full Text Available Aim: to identify the phenotypic characteristics of indeterminate connective tissue dysplasia, which help to predict the progression of varicose veins of lower extremities and disease recurrence after surgery. Material and Methods. The long-term results of surgical treatment of 60 patients with varicose veins of lower extremities in a 5-year period after phlebectomy were analyzed. The phenotypic characteristics of indeterminate connective tissue dysplasia were researched. 24 patients had recurrence of varicose veins of lower extremities associated with disease progression; 36 patients did not have recurrence of varicose veins of lower extremities. Results. All the patients demonstrated the signs of indeterminate connective tissue dysplasia, whereas their frequency was different. There were specified nine phenotypic characteristics of indeterminate connective tissue dysplasia, which were significantly more frequent for patients with recurrence of varicose vein disease of lower extremities: 1 postural abnormality, 2 flat foot, 3 skin pallor, 4 hyperextension of skin, 5 positive "wrist test", 6 positive "pollex test", 7 diastasis recti abdominis, 8 myopia, 9 hematomas which form quickly. Conclusion. The determined sum of phenotypic characters of indeterminate connective tissue dysplasia allows to predict progression of varicose vein disease of lower extremities, and offers new opportunities for improving the results of surgical treatment via developing special therapeutic measures aimed at improving lifestyle and dysplasia treatment.

  7. Skin Complications

    Science.gov (United States)

    ... Text Size: A A A Listen En Español Skin Complications Diabetes can affect every part of the ... lipoidica diabeticorum, diabetic blisters, and eruptive xanthomatosis. General Skin Conditions Bacterial Infections Several kinds of bacterial infections ...

  8. Diphtheria Complications

    Science.gov (United States)

    ... Search Form Controls Cancel Submit Search The CDC Diphtheria Note: Javascript is disabled or is not supported ... message, please visit this page: About CDC.gov . Diphtheria Home About Diphtheria Causes and Transmission Symptoms Complications ...

  9. Scaling Qualitative Probability

    OpenAIRE

    Burgin, Mark

    2017-01-01

    There are different approaches to qualitative probability, which includes subjective probability. We developed a representation of qualitative probability based on relational systems, which allows modeling uncertainty by probability structures and is more coherent than existing approaches. This setting makes it possible proving that any comparative probability is induced by some probability structure (Theorem 2.1), that classical probability is a probability structure (Theorem 2.2) and that i...

  10. Tissue expander complications in plastic surgery: a 10-year experience Complicações de expansores teciduais em cirurgia plástica: dez anos de experiência

    Directory of Open Access Journals (Sweden)

    Marcelo Sacramento Cunha

    2002-06-01

    Full Text Available INTRODUCTION: Tissue expanders have been of great value in plastic surgery. Tissue expansion was developed for a specific indication; however, within a very short time, the concept of tissue expansion found wide applicability. From 1990 to 1999, 315 expanders in 164 patients were utilized. A retrospective analysis of complications and prognostic factors for complications were done. METHODS: The indications for tissue expansion were burns (50%, trauma (32%, and sequelae of previous surgery (8.8%. The expanders were inserted most frequently in the scalp, trunk and neck. RESULTS: There were 22.2% of complications and the most common were expander exposure (50%, infection (24% and bad function of the expander (12.8%. The present study revealed an increased rate of minor complications in the group of 0 to 10 years of age and an increased rate of major complications for face and neck expansions compared to trunk expansion. There were no increased complication rates for the other age and anatomic site groups, previous expansion, concomitant expansion and type of expander used. CONCLUSIONS: The outcomes from tissue expansion procedures done in our hospital are similar to those reported in the literature. Tissue expansion is a good and safe technique.INTRODUÇÃO: A utilização de expansores teciduais tem sido de grande importância para a Cirurgia Plástica. Inicialmente descritos para correção de uma deformidade específica, logo tiveram sua utilização ampliada para deformidades congênitas e adquiridas. Foram utilizados 315 expansores em 164 pacientes no período de Janeiro de 1990 a Dezembro de 1999. Uma análise retrospectiva das complicações e fatores prognósticos para complicações foi realizada. MÉTODO: As deformidades tratadas mais freqüentes foram seqüelas de queimaduras (50%, seqüelas de traumas (32% e seqüelas de cirurgias prévias (8,8%. Os sítios anatômicos em que mais freqüentemente foram utilizados compreenderam face e

  11. SU-E-T-214: Comparison of Treatment Techniques for Dupuytren’s Contracture and Risk Assessment of Normal Tissue Complications

    International Nuclear Information System (INIS)

    Arentsen, L; Lopater, Z; Dusenbery, K; Gerbi, B

    2015-01-01

    Purpose: Duputren’s contracture (DC) is a benign disease characterized by abnormal thickening of the fascial surfaces of the hands or feet causing curling of the surface, functional impairment, weakness, and pain. The purpose of the investigation is to describe the radiation treatment approaches, compare these techniques, and discuss the potential side effects and complications of these techniques. Methods: Early stage DC has been treated with 120 kVp X rays but also with high-energy electrons or photons. High-energy electrons have been the radiation of choice but severe contracture of the hand makes it difficult to produce a plan with acceptable dose uniformity. High-energy photons can overcome this difficulty either by directing a beam onto the palmer or back of the surface of the hand, including bolus to maximize the surface dose. We calculated the dose to the bone for the 120 kVp treatment using published %DD data and mass energy absorption coefficients for bone and muscle. Results: The dose to underlying bone from megavoltage photons and electrons is essentially the same, but dose to the bone for using 120 kVp can be 4–5 times greater due to the photoelectric effect. For the 30 Gy dose deliver using this technique, the dose to the bone could be 84–105 Gy after taking the penetration of the beam into account. After radiotherapy, there is often decreased osteoblastic activity and vascular fibrosis that leads to osteitis, atrophy, and decreased metabolic bone activity. Incidence of fractures occurs routinely above 60 Gy with higher doses potentially leading to higher incidences of bone complications. Conclusion: Radiation therapy for DC using low-energy X rays can deliver a prohibitively high dose to the underlying bone potentially leading to severe bone complications

  12. Neuromuscular complications of thyrotoxicosis.

    Science.gov (United States)

    Kung, Annie W C

    2007-11-01

    Thyroid hormones exert multiple effects on the neuromuscular system and the brain, with the most important being their role in stimulating the development and differentiation of the neuromuscular system and brain in foetal and neonatal life. In the presence of hyperthyroidism, muscular and neurological symptoms may be the presenting clinical features of the disease. The frequency and severity of neuromuscular complications vary considerably and are probably related to the degree of hyperthyroidism, although in some patients the neuromuscular dysfunction is caused by associated disorders rather than by hyperthyroidism per se. This update focuses on the most common neurological and muscular disorders that occur in patients with thyrotoxicosis. It is beyond the scope of this paper to discuss thyroid eye disease and cardiac complications, in themselves separate complications of specific myocytes.

  13. On Probability Leakage

    OpenAIRE

    Briggs, William M.

    2012-01-01

    The probability leakage of model M with respect to evidence E is defined. Probability leakage is a kind of model error. It occurs when M implies that events $y$, which are impossible given E, have positive probability. Leakage does not imply model falsification. Models with probability leakage cannot be calibrated empirically. Regression models, which are ubiquitous in statistical practice, often evince probability leakage.

  14. The maximum entropy method of moments and Bayesian probability theory

    Science.gov (United States)

    Bretthorst, G. Larry

    2013-08-01

    The problem of density estimation occurs in many disciplines. For example, in MRI it is often necessary to classify the types of tissues in an image. To perform this classification one must first identify the characteristics of the tissues to be classified. These characteristics might be the intensity of a T1 weighted image and in MRI many other types of characteristic weightings (classifiers) may be generated. In a given tissue type there is no single intensity that characterizes the tissue, rather there is a distribution of intensities. Often this distributions can be characterized by a Gaussian, but just as often it is much more complicated. Either way, estimating the distribution of intensities is an inference problem. In the case of a Gaussian distribution, one must estimate the mean and standard deviation. However, in the Non-Gaussian case the shape of the density function itself must be inferred. Three common techniques for estimating density functions are binned histograms [1, 2], kernel density estimation [3, 4], and the maximum entropy method of moments [5, 6]. In the introduction, the maximum entropy method of moments will be reviewed. Some of its problems and conditions under which it fails will be discussed. Then in later sections, the functional form of the maximum entropy method of moments probability distribution will be incorporated into Bayesian probability theory. It will be shown that Bayesian probability theory solves all of the problems with the maximum entropy method of moments. One gets posterior probabilities for the Lagrange multipliers, and, finally, one can put error bars on the resulting estimated density function.

  15. Probability 1/e

    Science.gov (United States)

    Koo, Reginald; Jones, Martin L.

    2011-01-01

    Quite a number of interesting problems in probability feature an event with probability equal to 1/e. This article discusses three such problems and attempts to explain why this probability occurs with such frequency.

  16. Probability an introduction

    CERN Document Server

    Goldberg, Samuel

    1960-01-01

    Excellent basic text covers set theory, probability theory for finite sample spaces, binomial theorem, probability distributions, means, standard deviations, probability function of binomial distribution, more. Includes 360 problems with answers for half.

  17. Analysis of IRS-1-mediated phosphatidylinositol 3-kinase activation in the adipose tissue of polycystic ovary syndrome patients complicated with insulin resistance

    Energy Technology Data Exchange (ETDEWEB)

    Yongli, Chu [Yantai Yuhuangding Hospital, Yantai (China). Dept. of Obstetrics and Gynecology; Hongyu, Qiu; Yongyu, Sun; Min, Li; Hongfa, Li

    2004-04-01

    Objective: To investigate the insulin receptor substance-1 (IRS-1)-mediated phosphatidylinositol-3 (PI-3) kinase activity in adipose tissue of polycystic ovary syndrome (PCOS) patients, and to explore molecular mechanisms of insulin resistance of PCOS. Methods: Blood and adipose tissue samples from patients with PCOS with insulin resistance (n=19), PCOS without insulin resistance (n=10) and controls (n=15) were collected. Serum luteinizing hormone (LH), follicle stimulating hormone (FSH), testosterone (T) were measured by chemiluminescence assay. Fasting insulin (FIN) was measured by radioimmunoassay. Fasting plasma glucose (FPG) was measured by oxidase assay. Insulin resistance index (IR) was calculated using homeostasis model assessment (HOMA) to analyze the relationship between these markers and insulin resistance. The tyrosine phosphorylation of IRS-1 was measured by immunoprecipitation and enhanced chemiluminescent immunoblotting technique. PI-3 kinase activity was detected by immunoprecipitation, thin-layer chromatography and gamma scintillation counting. The results were analyzed by statistical methods. Results: 1) The levels of serum LH, LH/FSH, T, FIN and HOMA-IR in PCOS without insulin resistance were significantly higher than those of control group (all P<0.05); the levels of serum LH, LH/FSH, T, FIN and HOMA-IR in PCOS with insulin resistance were significantly higher than those of PCOS without insulin resistance (all P<0.05). 2) The tyrosine phosphorylation analysis of IRS-1 showed that IRS-1 tyrosine phosphorylation was significantly decreased in PCOS with insulin resistance compared to that of PCOS without insulin resistance and control groups (P<0.01). 3) PI-3 kinase activity was significantly decreased (P<0.01) and negatively correlated with HOMA-IR. Conclusion: In consequence of the weaker signal caused by the change of upper stream signal molecule IRS-1 tyrosine phosphorylation, PI-3 kinase activity decreased, it affects the insulin signal

  18. Analysis of IRS-1-mediated phosphatidylinositol 3-kinase activation in the adipose tissue of polycystic ovary syndrome patients complicated with insulin resistance

    International Nuclear Information System (INIS)

    Chu Yongli; Qiu Hongyu; Sun Yongyu; Li Min; Li Hongfa

    2004-01-01

    Objective: To investigate the insulin receptor substance-1 (IRS-1)-mediated phosphatidylinositol-3 (PI-3) kinase activity in adipose tissue of polycystic ovary syndrome (PCOS) patients, and to explore molecular mechanisms of insulin resistance of PCOS. Methods: Blood and adipose tissue samples from patients with PCOS with insulin resistance (n=19), PCOS without insulin resistance (n=10) and controls (n=15) were collected. Serum luteinizing hormone (LH), follicle stimulating hormone (FSH), testosterone (T) were measured by chemiluminescence assay. Fasting insulin (FIN) was measured by radioimmunoassay. Fasting plasma glucose (FPG) was measured by oxidase assay. Insulin resistance index (IR) was calculated using homeostasis model assessment (HOMA) to analyze the relationship between these markers and insulin resistance. The tyrosine phosphorylation of IRS-1 was measured by immunoprecipitation and enhanced chemiluminescent immunoblotting technique. PI-3 kinase activity was detected by immunoprecipitation, thin-layer chromatography and gamma scintillation counting. The results were analyzed by statistical methods. Results: 1) The levels of serum LH, LH/FSH, T, FIN and HOMA-IR in PCOS without insulin resistance were significantly higher than those of control group (all P<0.05); the levels of serum LH, LH/FSH, T, FIN and HOMA-IR in PCOS with insulin resistance were significantly higher than those of PCOS without insulin resistance (all P<0.05). 2) The tyrosine phosphorylation analysis of IRS-1 showed that IRS-1 tyrosine phosphorylation was significantly decreased in PCOS with insulin resistance compared to that of PCOS without insulin resistance and control groups (P<0.01). 3) PI-3 kinase activity was significantly decreased (P<0.01) and negatively correlated with HOMA-IR. Conclusion: In consequence of the weaker signal caused by the change of upper stream signal molecule IRS-1 tyrosine phosphorylation, PI-3 kinase activity decreased, it affects the insulin signal

  19. Quantum probability measures and tomographic probability densities

    NARCIS (Netherlands)

    Amosov, GG; Man'ko, [No Value

    2004-01-01

    Using a simple relation of the Dirac delta-function to generalized the theta-function, the relationship between the tomographic probability approach and the quantum probability measure approach with the description of quantum states is discussed. The quantum state tomogram expressed in terms of the

  20. Complications of shoulder arthroscopy.

    Science.gov (United States)

    Moen, Todd C; Rudolph, Glen H; Caswell, Kyle; Espinoza, Christopher; Burkhead, Wayne Z; Krishnan, Sumant G

    2014-07-01

    Over the past 20 to 30 years, arthroscopic shoulder techniques have become increasingly popular. Although these techniques have several advantages over open surgery, surgical complications are no less prevalent or devastating than those associated with open techniques. Some of the complications associated with arthroscopic shoulder surgery include recurrent instability, soft-tissue injury, and neurapraxia. These complications can be minimized with thoughtful consideration of the surgical indications, careful patient selection and positioning, and a thorough knowledge of the shoulder anatomy. Deep infection following arthroscopic shoulder surgery is rare; however, the shoulder is particularly susceptible to Propionibacterium acnes infection, which is mildly virulent and has a benign presentation. The surgeon must maintain a high index of suspicion for this infection. Thromboemoblic complications associated with arthroscopic shoulder techniques are also rare, and studies have shown that pharmacologic prophylaxis has minimal efficacy in preventing these complications. Because high-quality studies on the subject are lacking, minimal evidence is available to suggest strategies for prevention. Copyright 2014 by the American Academy of Orthopaedic Surgeons.

  1. Toward a generalized probability theory: conditional probabilities

    International Nuclear Information System (INIS)

    Cassinelli, G.

    1979-01-01

    The main mathematical object of interest in the quantum logic approach to the foundations of quantum mechanics is the orthomodular lattice and a set of probability measures, or states, defined by the lattice. This mathematical structure is studied per se, independently from the intuitive or physical motivation of its definition, as a generalized probability theory. It is thought that the building-up of such a probability theory could eventually throw light on the mathematical structure of Hilbert-space quantum mechanics as a particular concrete model of the generalized theory. (Auth.)

  2. Philosophical theories of probability

    CERN Document Server

    Gillies, Donald

    2000-01-01

    The Twentieth Century has seen a dramatic rise in the use of probability and statistics in almost all fields of research. This has stimulated many new philosophical ideas on probability. Philosophical Theories of Probability is the first book to present a clear, comprehensive and systematic account of these various theories and to explain how they relate to one another. Gillies also offers a distinctive version of the propensity theory of probability, and the intersubjective interpretation, which develops the subjective theory.

  3. Non-Archimedean Probability

    NARCIS (Netherlands)

    Benci, Vieri; Horsten, Leon; Wenmackers, Sylvia

    We propose an alternative approach to probability theory closely related to the framework of numerosity theory: non-Archimedean probability (NAP). In our approach, unlike in classical probability theory, all subsets of an infinite sample space are measurable and only the empty set gets assigned

  4. Interpretations of probability

    CERN Document Server

    Khrennikov, Andrei

    2009-01-01

    This is the first fundamental book devoted to non-Kolmogorov probability models. It provides a mathematical theory of negative probabilities, with numerous applications to quantum physics, information theory, complexity, biology and psychology. The book also presents an interesting model of cognitive information reality with flows of information probabilities, describing the process of thinking, social, and psychological phenomena.

  5. Complications of lower limb phlebography

    Energy Technology Data Exchange (ETDEWEB)

    Zeitler, E; Milbert, L; Richter, E I; Ringelmann, W; Strohm, C

    1983-06-01

    Some rare, but serious, complications during leg and pelvic phlebography are described. One fatal pulmonary embolus and six cases of necrosis of the dorsum of the foot due to phlebography were encountered. The causes, pathogenetic factors and other possible complications are discussed. Extravasation of contrast due to puncture on the lateral side of the foot, or near the ankle joint, leads to the formation of a contrast bleb which may proceed to tissue necrosis.

  6. Complications of cancer therapy

    International Nuclear Information System (INIS)

    Moskowitz, P.S.; Parker, B.R.

    1985-01-01

    The purpose of this chapter is to review systematically the toxicity of contemporary chemotherapy and irradiation on normal tissues of growing children. Whenever possible, the separate toxicity of chemotherapy, irradiation, and combination therapy is addressed. However, it is not always possible to quantitate specifically such reactions in the face of multiple drug therapy, which may enhance radiation injury or reactivate prior radiation injury. Prior detailed reviews have provided important sources of information concerning radiation injury for this more general discussion. The information provided will assist both the clinician and the radiologist in the recognition of early and late complications of therapy in pediatric oncology

  7. Complications of Macular Peeling

    Science.gov (United States)

    Asencio-Duran, Mónica; Manzano-Muñoz, Beatriz; Vallejo-García, José Luis; García-Martínez, Jesús

    2015-01-01

    Macular peeling refers to the surgical technique for the removal of preretinal tissue or the internal limiting membrane (ILM) in the macula for several retinal disorders, ranging from epiretinal membranes (primary or secondary to diabetic retinopathy, retinal detachment…) to full-thickness macular holes, macular edema, foveal retinoschisis, and others. The technique has evolved in the last two decades, and the different instrumentations and adjuncts have progressively advanced turning into a safer, easier, and more useful tool for the vitreoretinal surgeon. Here, we describe the main milestones of macular peeling, drawing attention to its associated complications. PMID:26425351

  8. Probability of obliteration and management risk following gamma knife surgery for cerebral AVM

    International Nuclear Information System (INIS)

    Karlsson, B.; Lax, I.

    1998-01-01

    In order to define the optimal treatment for an AVM patient, the probability of cure and the management risk following the treatment must be estimated before the treatment. Here, Gamma Knife surgery has an advantage over microsurgery and embolization with it's reproducibility within the variability of the individual radiation sensitivity. Based on more than 2000 treatments, we have developed models to predict the probability for obliteration, the risk for radioinduced complications and the probability for a post treatment hemorrhage within the first two years following a Gamma Knife treatment. The factors determining the overall outcome are the absorbed dose in the target and the brain, the AVM volume and location and the age and clinical history of the patient. The probability for obliteration equals 35,69 * ln(D min )-39,66 and is AVM volume independent. The risk for radioinduced complications relates to the average dose in the 20 cm 3 tissue receiving the most radiation, and it is also related to the clinical history of the patient and the AVM location. Finally, the risk for post treatment hemorrhage increases with the age of the patient, and is higher for larger AVM. It decreases with increasing amount of radiation given, and it is independent of the clinical history of the patient. For retreatments, the model for prediction of obliteration is valid, but the risk for radioinduced complications is higher and the risk for post treatment hemorrhage lower as compared to following the first treatment. (author)

  9. Postanesthetic ulceration of palate: A rare complication

    OpenAIRE

    Gupta, Ramesh; Garg, Meenu; Pawah, Salil; Gupta, Ajay

    2016-01-01

    The routine dental practice involves various dental procedures which needs the application of local anesthetics. Generally, there are very few complications associated with these procedures. Complications such as tissue necrosis can occur following the rapid injection of local anesthetic solutions. Palate is a favorable site for soft tissue lesions, various factors such as direct effects of the drug, blanching of the tissues during injection, a relatively poor blood supply, and reactivation o...

  10. High burden of complicated skin and soft tissue infections in the Indigenous population of Central Australia due to dominant Panton Valentine leucocidin clones ST93-MRSA and CC121-MSSA.

    Science.gov (United States)

    Harch, Susan A J; MacMorran, Eleanor; Tong, Steven Y C; Holt, Deborah C; Wilson, Judith; Athan, Eugene; Hewagama, Saliya

    2017-06-07

    Superficial skin and soft tissue infections (SSTIs) are common among the Indigenous population of the desert regions of Central Australia. However, the overall burden of disease and molecular epidemiology of Staphylococcus aureus complicated SSTIs has yet to be described in this unique population. Alice Springs Hospital (ASH) admission data was interrogated to establish the population incidence of SSTIs. A prospective observational study was conducted on a subset of S. aureus complicated SSTIs (carbuncles and furuncles requiring surgical intervention) presenting during a one month period to further characterize the clinical and molecular epidemiology. High resolution melting analysis was used for clonal complex discrimination. Real-time polymerase chain reaction identifying the lukF component of the Panton Valentine leucocidin (pvl) gene determined pvl status. Clinical and outcome data was obtained from the ASH medical and Northern Territory shared electronic health records. SSTIs represented 2.1% of ASH admissions during 2014. 82.6% occurred in Indigenous patients (n = 382) with an estimated incidence of 18.9 per 1, 000 people years compared to the non-Indigenous population of 2.9 per 1000, with an incident rate ratio of 6.6 (95% confidence interval 5.1-8.5). Clinical and molecular analysis was performed on 50 isolates from 47 patients. Community-associated methicillin-resistant S. aureus (CA-MRSA) predominated (57% of isolates). The high burden of SSTIs is partly explained by the prevalence of pvl positive strains of S. aureus (90% isolates) for both CA-MRSA and methicillin-susceptible S. aureus (MSSA). ST93-MRSA and CC121-MSSA were the most prevalent clones. SSTIs due to ST93-MRSA were more likely to require further debridement (p = 0.039), however they also more frequently received inactive antimicrobial therapy (p population when antimicrobial therapy is indicated. Prompt surgical intervention remains the cornerstone of treatment.

  11. Foundations of probability

    International Nuclear Information System (INIS)

    Fraassen, B.C. van

    1979-01-01

    The interpretation of probabilities in physical theories are considered, whether quantum or classical. The following points are discussed 1) the functions P(μ, Q) in terms of which states and propositions can be represented, are classical (Kolmogoroff) probabilities, formally speaking, 2) these probabilities are generally interpreted as themselves conditional, and the conditions are mutually incompatible where the observables are maximal and 3) testing of the theory typically takes the form of confronting the expectation values of observable Q calculated with probability measures P(μ, Q) for states μ; hence, of comparing the probabilities P(μ, Q)(E) with the frequencies of occurrence of the corresponding events. It seems that even the interpretation of quantum mechanics, in so far as it concerns what the theory says about the empirical (i.e. actual, observable) phenomena, deals with the confrontation of classical probability measures with observable frequencies. This confrontation is studied. (Auth./C.F.)

  12. The quantum probability calculus

    International Nuclear Information System (INIS)

    Jauch, J.M.

    1976-01-01

    The Wigner anomaly (1932) for the joint distribution of noncompatible observables is an indication that the classical probability calculus is not applicable for quantum probabilities. It should, therefore, be replaced by another, more general calculus, which is specifically adapted to quantal systems. In this article this calculus is exhibited and its mathematical axioms and the definitions of the basic concepts such as probability field, random variable, and expectation values are given. (B.R.H)

  13. Choice Probability Generating Functions

    DEFF Research Database (Denmark)

    Fosgerau, Mogens; McFadden, Daniel L; Bierlaire, Michel

    This paper considers discrete choice, with choice probabilities coming from maximization of preferences from a random utility field perturbed by additive location shifters (ARUM). Any ARUM can be characterized by a choice-probability generating function (CPGF) whose gradient gives the choice...... probabilities, and every CPGF is consistent with an ARUM. We relate CPGF to multivariate extreme value distributions, and review and extend methods for constructing CPGF for applications....

  14. Probability of satellite collision

    Science.gov (United States)

    Mccarter, J. W.

    1972-01-01

    A method is presented for computing the probability of a collision between a particular artificial earth satellite and any one of the total population of earth satellites. The collision hazard incurred by the proposed modular Space Station is assessed using the technique presented. The results of a parametric study to determine what type of satellite orbits produce the greatest contribution to the total collision probability are presented. Collision probability for the Space Station is given as a function of Space Station altitude and inclination. Collision probability was also parameterized over miss distance and mission duration.

  15. Choice probability generating functions

    DEFF Research Database (Denmark)

    Fosgerau, Mogens; McFadden, Daniel; Bierlaire, Michel

    2013-01-01

    This paper considers discrete choice, with choice probabilities coming from maximization of preferences from a random utility field perturbed by additive location shifters (ARUM). Any ARUM can be characterized by a choice-probability generating function (CPGF) whose gradient gives the choice...... probabilities, and every CPGF is consistent with an ARUM. We relate CPGF to multivariate extreme value distributions, and review and extend methods for constructing CPGF for applications. The choice probabilities of any ARUM may be approximated by a cross-nested logit model. The results for ARUM are extended...

  16. Handbook of probability

    CERN Document Server

    Florescu, Ionut

    2013-01-01

    THE COMPLETE COLLECTION NECESSARY FOR A CONCRETE UNDERSTANDING OF PROBABILITY Written in a clear, accessible, and comprehensive manner, the Handbook of Probability presents the fundamentals of probability with an emphasis on the balance of theory, application, and methodology. Utilizing basic examples throughout, the handbook expertly transitions between concepts and practice to allow readers an inclusive introduction to the field of probability. The book provides a useful format with self-contained chapters, allowing the reader easy and quick reference. Each chapter includes an introductio

  17. Real analysis and probability

    CERN Document Server

    Ash, Robert B; Lukacs, E

    1972-01-01

    Real Analysis and Probability provides the background in real analysis needed for the study of probability. Topics covered range from measure and integration theory to functional analysis and basic concepts of probability. The interplay between measure theory and topology is also discussed, along with conditional probability and expectation, the central limit theorem, and strong laws of large numbers with respect to martingale theory.Comprised of eight chapters, this volume begins with an overview of the basic concepts of the theory of measure and integration, followed by a presentation of var

  18. Renal posttransplant's vascular complications

    Directory of Open Access Journals (Sweden)

    Bašić Dragoslav

    2003-01-01

    Full Text Available INTRODUCTION Despite high graft and recipient survival figures worldwide today, a variety of technical complications can threaten the transplant in the postoperative period. Vascular complications are commonly related to technical problems in establishing vascular continuity or to damage that occurs during donor nephrectomy or preservation [13]. AIM The aim of the presenting study is to evaluate counts and rates of vascular complications after renal transplantation and to compare the outcome by donor type. MATERIAL AND METHODS A total of 463 kidneys (319 from living related donor LD and 144 from cadaveric donor - CD were transplanted during the period between June 1975 and December 1998 at the Urology & Nephrology Institute of Clinical Centre of Serbia in Belgrade. Average recipients' age was 33.7 years (15-54 in LD group and 39.8 (19-62 in CD group. Retrospectively, we analyzed medical records of all recipients. Statistical analysis is estimated using Hi-squared test and Fischer's test of exact probability. RESULTS Major vascular complications including vascular anastomosis thrombosis, internal iliac artery stenosis, internal iliac artery rupture obliterant vasculitis and external iliac vein rupture were analyzed. In 25 recipients (5.4% some of major vascular complications were detected. Among these cases, 22 of them were from CD group vs. three from LD group. Relative rate of these complications was higher in CD group vs. LD group (p<0.0001. Among these complications dominant one was vascular anastomosis thrombosis which occurred in 18 recipients (17 from CD vs. one from LD. Of these recipients 16 from CD lost the graft, while the rest of two (one from each group had lethal outcome. DISCUSSION Thrombosis of renal allograft vascular anastomosis site is the most severe complication following renal transplantation. In the literature, renal allograft thrombosis is reported with different incidence rates, from 0.5-4% [14, 15, 16]. Data from the

  19. Introduction to probability

    CERN Document Server

    Freund, John E

    1993-01-01

    Thorough, lucid coverage of permutations and factorials, probabilities and odds, frequency interpretation, mathematical expectation, decision making, postulates of probability, rule of elimination, binomial distribution, geometric distribution, standard deviation, law of large numbers, and much more. Exercises with some solutions. Summary. Bibliography. Includes 42 black-and-white illustrations. 1973 edition.

  20. Probability, Nondeterminism and Concurrency

    DEFF Research Database (Denmark)

    Varacca, Daniele

    Nondeterminism is modelled in domain theory by the notion of a powerdomain, while probability is modelled by that of the probabilistic powerdomain. Some problems arise when we want to combine them in order to model computation in which both nondeterminism and probability are present. In particula...

  1. Janus-faced probability

    CERN Document Server

    Rocchi, Paolo

    2014-01-01

    The problem of probability interpretation was long overlooked before exploding in the 20th century, when the frequentist and subjectivist schools formalized two conflicting conceptions of probability. Beyond the radical followers of the two schools, a circle of pluralist thinkers tends to reconcile the opposing concepts. The author uses two theorems in order to prove that the various interpretations of probability do not come into opposition and can be used in different contexts. The goal here is to clarify the multifold nature of probability by means of a purely mathematical approach and to show how philosophical arguments can only serve to deepen actual intellectual contrasts. The book can be considered as one of the most important contributions in the analysis of probability interpretation in the last 10-15 years.

  2. Probability and Measure

    CERN Document Server

    Billingsley, Patrick

    2012-01-01

    Praise for the Third Edition "It is, as far as I'm concerned, among the best books in math ever written....if you are a mathematician and want to have the top reference in probability, this is it." (Amazon.com, January 2006) A complete and comprehensive classic in probability and measure theory Probability and Measure, Anniversary Edition by Patrick Billingsley celebrates the achievements and advancements that have made this book a classic in its field for the past 35 years. Now re-issued in a new style and format, but with the reliable content that the third edition was revered for, this

  3. The concept of probability

    International Nuclear Information System (INIS)

    Bitsakis, E.I.; Nicolaides, C.A.

    1989-01-01

    The concept of probability is now, and always has been, central to the debate on the interpretation of quantum mechanics. Furthermore, probability permeates all of science, as well as our every day life. The papers included in this volume, written by leading proponents of the ideas expressed, embrace a broad spectrum of thought and results: mathematical, physical epistemological, and experimental, both specific and general. The contributions are arranged in parts under the following headings: Following Schroedinger's thoughts; Probability and quantum mechanics; Aspects of the arguments on nonlocality; Bell's theorem and EPR correlations; Real or Gedanken experiments and their interpretation; Questions about irreversibility and stochasticity; and Epistemology, interpretation and culture. (author). refs.; figs.; tabs

  4. Probability for statisticians

    CERN Document Server

    Shorack, Galen R

    2017-01-01

    This 2nd edition textbook offers a rigorous introduction to measure theoretic probability with particular attention to topics of interest to mathematical statisticians—a textbook for courses in probability for students in mathematical statistics. It is recommended to anyone interested in the probability underlying modern statistics, providing a solid grounding in the probabilistic tools and techniques necessary to do theoretical research in statistics. For the teaching of probability theory to post graduate statistics students, this is one of the most attractive books available. Of particular interest is a presentation of the major central limit theorems via Stein's method either prior to or alternative to a characteristic function presentation. Additionally, there is considerable emphasis placed on the quantile function as well as the distribution function. The bootstrap and trimming are both presented. Martingale coverage includes coverage of censored data martingales. The text includes measure theoretic...

  5. Concepts of probability theory

    CERN Document Server

    Pfeiffer, Paul E

    1979-01-01

    Using the Kolmogorov model, this intermediate-level text discusses random variables, probability distributions, mathematical expectation, random processes, more. For advanced undergraduates students of science, engineering, or math. Includes problems with answers and six appendixes. 1965 edition.

  6. Probability and Bayesian statistics

    CERN Document Server

    1987-01-01

    This book contains selected and refereed contributions to the "Inter­ national Symposium on Probability and Bayesian Statistics" which was orga­ nized to celebrate the 80th birthday of Professor Bruno de Finetti at his birthplace Innsbruck in Austria. Since Professor de Finetti died in 1985 the symposium was dedicated to the memory of Bruno de Finetti and took place at Igls near Innsbruck from 23 to 26 September 1986. Some of the pa­ pers are published especially by the relationship to Bruno de Finetti's scientific work. The evolution of stochastics shows growing importance of probability as coherent assessment of numerical values as degrees of believe in certain events. This is the basis for Bayesian inference in the sense of modern statistics. The contributions in this volume cover a broad spectrum ranging from foundations of probability across psychological aspects of formulating sub­ jective probability statements, abstract measure theoretical considerations, contributions to theoretical statistics an...

  7. Probability and Statistical Inference

    OpenAIRE

    Prosper, Harrison B.

    2006-01-01

    These lectures introduce key concepts in probability and statistical inference at a level suitable for graduate students in particle physics. Our goal is to paint as vivid a picture as possible of the concepts covered.

  8. Probabilities in physics

    CERN Document Server

    Hartmann, Stephan

    2011-01-01

    Many results of modern physics--those of quantum mechanics, for instance--come in a probabilistic guise. But what do probabilistic statements in physics mean? Are probabilities matters of objective fact and part of the furniture of the world, as objectivists think? Or do they only express ignorance or belief, as Bayesians suggest? And how are probabilistic hypotheses justified and supported by empirical evidence? Finally, what does the probabilistic nature of physics imply for our understanding of the world? This volume is the first to provide a philosophical appraisal of probabilities in all of physics. Its main aim is to make sense of probabilistic statements as they occur in the various physical theories and models and to provide a plausible epistemology and metaphysics of probabilities. The essays collected here consider statistical physics, probabilistic modelling, and quantum mechanics, and critically assess the merits and disadvantages of objectivist and subjectivist views of probabilities in these fie...

  9. Probability an introduction

    CERN Document Server

    Grimmett, Geoffrey

    2014-01-01

    Probability is an area of mathematics of tremendous contemporary importance across all aspects of human endeavour. This book is a compact account of the basic features of probability and random processes at the level of first and second year mathematics undergraduates and Masters' students in cognate fields. It is suitable for a first course in probability, plus a follow-up course in random processes including Markov chains. A special feature is the authors' attention to rigorous mathematics: not everything is rigorous, but the need for rigour is explained at difficult junctures. The text is enriched by simple exercises, together with problems (with very brief hints) many of which are taken from final examinations at Cambridge and Oxford. The first eight chapters form a course in basic probability, being an account of events, random variables, and distributions - discrete and continuous random variables are treated separately - together with simple versions of the law of large numbers and the central limit th...

  10. Probability in physics

    CERN Document Server

    Hemmo, Meir

    2012-01-01

    What is the role and meaning of probability in physical theory, in particular in two of the most successful theories of our age, quantum physics and statistical mechanics? Laws once conceived as universal and deterministic, such as Newton‘s laws of motion, or the second law of thermodynamics, are replaced in these theories by inherently probabilistic laws. This collection of essays by some of the world‘s foremost experts presents an in-depth analysis of the meaning of probability in contemporary physics. Among the questions addressed are: How are probabilities defined? Are they objective or subjective? What is their  explanatory value? What are the differences between quantum and classical probabilities? The result is an informative and thought-provoking book for the scientifically inquisitive. 

  11. Probability in quantum mechanics

    Directory of Open Access Journals (Sweden)

    J. G. Gilson

    1982-01-01

    Full Text Available By using a fluid theory which is an alternative to quantum theory but from which the latter can be deduced exactly, the long-standing problem of how quantum mechanics is related to stochastic processes is studied. It can be seen how the Schrödinger probability density has a relationship to time spent on small sections of an orbit, just as the probability density has in some classical contexts.

  12. Quantum computing and probability.

    Science.gov (United States)

    Ferry, David K

    2009-11-25

    Over the past two decades, quantum computing has become a popular and promising approach to trying to solve computationally difficult problems. Missing in many descriptions of quantum computing is just how probability enters into the process. Here, we discuss some simple examples of how uncertainty and probability enter, and how this and the ideas of quantum computing challenge our interpretations of quantum mechanics. It is found that this uncertainty can lead to intrinsic decoherence, and this raises challenges for error correction.

  13. Quantum computing and probability

    International Nuclear Information System (INIS)

    Ferry, David K

    2009-01-01

    Over the past two decades, quantum computing has become a popular and promising approach to trying to solve computationally difficult problems. Missing in many descriptions of quantum computing is just how probability enters into the process. Here, we discuss some simple examples of how uncertainty and probability enter, and how this and the ideas of quantum computing challenge our interpretations of quantum mechanics. It is found that this uncertainty can lead to intrinsic decoherence, and this raises challenges for error correction. (viewpoint)

  14. Analysis of clinical complication data for radiation hepatitis using a parallel architecture model

    International Nuclear Information System (INIS)

    Jackson, A.; Haken, R.K. ten; Robertson, J.M.; Kessler, M.L.; Kutcher, G.J.; Lawrence, T.S.

    1995-01-01

    Purpose: The detailed knowledge of dose volume distributions available from the three-dimensional (3D) conformal radiation treatment of tumors in the liver (reported elsewhere) offers new opportunities to quantify the effect of volume on the probability of producing radiation hepatitis. We aim to test a new parallel architecture model of normal tissue complication probability (NTCP) with these data. Methods and Materials: Complication data and dose volume histograms from a total of 93 patients with normal liver function, treated on a prospective protocol with 3D conformal radiation therapy and intraarterial hepatic fluorodeoxyuridine, were analyzed with a new parallel architecture model. Patient treatment fell into six categories differing in doses delivered and volumes irradiated. By modeling the radiosensitivity of liver subunits, we are able to use dose volume histograms to calculate the fraction of the liver damaged in each patient. A complication results if this fraction exceeds the patient's functional reserve. To determine the patient distribution of functional reserves and the subunit radiosensitivity, the maximum likelihood method was used to fit the observed complication data. Results: The parallel model fit the complication data well, although uncertainties on the functional reserve distribution and subunit radiosensitivy are highly correlated. Conclusion: The observed radiation hepatitis complications show a threshold effect that can be described well with a parallel architecture model. However, additional independent studies are required to better determine the parameters defining the functional reserve distribution and subunit radiosensitivity

  15. Postanesthetic ulceration of palate: A rare complication.

    Science.gov (United States)

    Gupta, Ramesh; Garg, Meenu; Pawah, Salil; Gupta, Ajay

    2016-01-01

    The routine dental practice involves various dental procedures which needs the application of local anesthetics. Generally, there are very few complications associated with these procedures. Complications such as tissue necrosis can occur following the rapid injection of local anesthetic solutions. Palate is a favorable site for soft tissue lesions, various factors such as direct effects of the drug, blanching of the tissues during injection, a relatively poor blood supply, and reactivation of the latent forms of herpes can all promote to tissue ischemia and a lesion in the palate.

  16. Hip complications following chemoradiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Jenkins, P.J.; Sebag Montefiore, D.J.; Arnott, S.J. [Saint Bartholomew`s Hospital, London (United Kingdom)

    1995-12-01

    Chemoradiotherapy protocols are a recent development in the management of tumours where preservation of organ function is important. It is now recognized that such combined treatment may produce adverse effects below the accepted dose thresholds for either modality. This enhancement of toxicity is generally thought to reflect depletion of stem cells within the tissue concerned. We report four patients who have developed avascular necrosis or fractures of the hip following chemoradiotherapy for carcinoma of the vulva or anus. These complications developed after a radiation dose of 4500 cGy in 20 fractions. The possible role of cytotoxic agents in sensitizing bone to radiation damage is discussed, and a novel mechanism is proposed to account for this phenomenon. (author).

  17. Hip complications following chemoradiotherapy

    International Nuclear Information System (INIS)

    Jenkins, P.J.; Sebag Montefiore, D.J.; Arnott, S.J.

    1995-01-01

    Chemoradiotherapy protocols are a recent development in the management of tumours where preservation of organ function is important. It is now recognized that such combined treatment may produce adverse effects below the accepted dose thresholds for either modality. This enhancement of toxicity is generally thought to reflect depletion of stem cells within the tissue concerned. We report four patients who have developed avascular necrosis or fractures of the hip following chemoradiotherapy for carcinoma of the vulva or anus. These complications developed after a radiation dose of 4500 cGy in 20 fractions. The possible role of cytotoxic agents in sensitizing bone to radiation damage is discussed, and a novel mechanism is proposed to account for this phenomenon. (author)

  18. The perception of probability.

    Science.gov (United States)

    Gallistel, C R; Krishan, Monika; Liu, Ye; Miller, Reilly; Latham, Peter E

    2014-01-01

    We present a computational model to explain the results from experiments in which subjects estimate the hidden probability parameter of a stepwise nonstationary Bernoulli process outcome by outcome. The model captures the following results qualitatively and quantitatively, with only 2 free parameters: (a) Subjects do not update their estimate after each outcome; they step from one estimate to another at irregular intervals. (b) The joint distribution of step widths and heights cannot be explained on the assumption that a threshold amount of change must be exceeded in order for them to indicate a change in their perception. (c) The mapping of observed probability to the median perceived probability is the identity function over the full range of probabilities. (d) Precision (how close estimates are to the best possible estimate) is good and constant over the full range. (e) Subjects quickly detect substantial changes in the hidden probability parameter. (f) The perceived probability sometimes changes dramatically from one observation to the next. (g) Subjects sometimes have second thoughts about a previous change perception, after observing further outcomes. (h) The frequency with which they perceive changes moves in the direction of the true frequency over sessions. (Explaining this finding requires 2 additional parametric assumptions.) The model treats the perception of the current probability as a by-product of the construction of a compact encoding of the experienced sequence in terms of its change points. It illustrates the why and the how of intermittent Bayesian belief updating and retrospective revision in simple perception. It suggests a reinterpretation of findings in the recent literature on the neurobiology of decision making. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

  19. Smoking, Labor, & Delivery: It's Complicated

    Science.gov (United States)

    You probably have mixed feelings about going into labor. On one hand, bringing a new life into the world is really exciting. On the other, it can be really scary to have a baby, especially if this is your first child. Unfortunately, it can be even scarier if you smoke. Research shows that smoking during pregnancy can lead to serious complications for you and your baby during labor and delivery.

  20. Irreversibility and conditional probability

    International Nuclear Information System (INIS)

    Stuart, C.I.J.M.

    1989-01-01

    The mathematical entropy - unlike physical entropy - is simply a measure of uniformity for probability distributions in general. So understood, conditional entropies have the same logical structure as conditional probabilities. If, as is sometimes supposed, conditional probabilities are time-reversible, then so are conditional entropies and, paradoxically, both then share this symmetry with physical equations of motion. The paradox is, of course that probabilities yield a direction to time both in statistical mechanics and quantum mechanics, while the equations of motion do not. The supposed time-reversibility of both conditionals seems also to involve a form of retrocausality that is related to, but possibly not the same as, that described by Costa de Beaurgard. The retrocausality is paradoxically at odds with the generally presumed irreversibility of the quantum mechanical measurement process. Further paradox emerges if the supposed time-reversibility of the conditionals is linked with the idea that the thermodynamic entropy is the same thing as 'missing information' since this confounds the thermodynamic and mathematical entropies. However, it is shown that irreversibility is a formal consequence of conditional entropies and, hence, of conditional probabilities also. 8 refs. (Author)

  1. The pleasures of probability

    CERN Document Server

    Isaac, Richard

    1995-01-01

    The ideas of probability are all around us. Lotteries, casino gambling, the al­ most non-stop polling which seems to mold public policy more and more­ these are a few of the areas where principles of probability impinge in a direct way on the lives and fortunes of the general public. At a more re­ moved level there is modern science which uses probability and its offshoots like statistics and the theory of random processes to build mathematical descriptions of the real world. In fact, twentieth-century physics, in embrac­ ing quantum mechanics, has a world view that is at its core probabilistic in nature, contrary to the deterministic one of classical physics. In addition to all this muscular evidence of the importance of probability ideas it should also be said that probability can be lots of fun. It is a subject where you can start thinking about amusing, interesting, and often difficult problems with very little mathematical background. In this book, I wanted to introduce a reader with at least a fairl...

  2. Experimental Probability in Elementary School

    Science.gov (United States)

    Andrew, Lane

    2009-01-01

    Concepts in probability can be more readily understood if students are first exposed to probability via experiment. Performing probability experiments encourages students to develop understandings of probability grounded in real events, as opposed to merely computing answers based on formulae.

  3. [Gastroplasty: complications and their prevention].

    Science.gov (United States)

    Schlienger, J L; Meyer, L; Rohr, S; Pradignac, A; Perrin, A E; Meyer, C; Simon, C

    2003-02-01

    Bariatric surgery is now frequently proposed for the treatment of morbid or complicated obesity since the introduction of minimally invasive laparoscopic anti-obesity operations such as the adjustable silicone gastric binding gastroplasty. However this reversible procedure in not always as safe as presumed and the results in weight loss may be sometimes disappointing. Side effects are common and early or late complications occured in more than 20% out of the patients. They are favoured by post operative eating disorders. Nutritional consequences are probably underestimated and are not limited to uncomfortable digestive symptoms. Some deficiencies in micronutriments have been described. The worsening of previous eating disorders or psychosocial abnormalities are not seldom. Gastroplasty is not an harmless procedure. A good selection in patients, a regular follow up, nutritional advices and psychosocial management by a multidisciplinar team are required to reduce complications after gastroplasty.

  4. Improving Ranking Using Quantum Probability

    OpenAIRE

    Melucci, Massimo

    2011-01-01

    The paper shows that ranking information units by quantum probability differs from ranking them by classical probability provided the same data used for parameter estimation. As probability of detection (also known as recall or power) and probability of false alarm (also known as fallout or size) measure the quality of ranking, we point out and show that ranking by quantum probability yields higher probability of detection than ranking by classical probability provided a given probability of ...

  5. Choice probability generating functions

    DEFF Research Database (Denmark)

    Fosgerau, Mogens; McFadden, Daniel; Bierlaire, Michel

    2010-01-01

    This paper establishes that every random utility discrete choice model (RUM) has a representation that can be characterized by a choice-probability generating function (CPGF) with specific properties, and that every function with these specific properties is consistent with a RUM. The choice...... probabilities from the RUM are obtained from the gradient of the CPGF. Mixtures of RUM are characterized by logarithmic mixtures of their associated CPGF. The paper relates CPGF to multivariate extreme value distributions, and reviews and extends methods for constructing generating functions for applications....... The choice probabilities of any ARUM may be approximated by a cross-nested logit model. The results for ARUM are extended to competing risk survival models....

  6. Probability and stochastic modeling

    CERN Document Server

    Rotar, Vladimir I

    2012-01-01

    Basic NotionsSample Space and EventsProbabilitiesCounting TechniquesIndependence and Conditional ProbabilityIndependenceConditioningThe Borel-Cantelli TheoremDiscrete Random VariablesRandom Variables and VectorsExpected ValueVariance and Other Moments. Inequalities for DeviationsSome Basic DistributionsConvergence of Random Variables. The Law of Large NumbersConditional ExpectationGenerating Functions. Branching Processes. Random Walk RevisitedBranching Processes Generating Functions Branching Processes Revisited More on Random WalkMarkov ChainsDefinitions and Examples. Probability Distributions of Markov ChainsThe First Step Analysis. Passage TimesVariables Defined on a Markov ChainErgodicity and Stationary DistributionsA Classification of States and ErgodicityContinuous Random VariablesContinuous DistributionsSome Basic Distributions Continuous Multivariate Distributions Sums of Independent Random Variables Conditional Distributions and ExpectationsDistributions in the General Case. SimulationDistribution F...

  7. Collision Probability Analysis

    DEFF Research Database (Denmark)

    Hansen, Peter Friis; Pedersen, Preben Terndrup

    1998-01-01

    It is the purpose of this report to apply a rational model for prediction of ship-ship collision probabilities as function of the ship and the crew characteristics and the navigational environment for MS Dextra sailing on a route between Cadiz and the Canary Islands.The most important ship and crew...... characteristics are: ship speed, ship manoeuvrability, the layout of the navigational bridge, the radar system, the number and the training of navigators, the presence of a look out etc. The main parameters affecting the navigational environment are ship traffic density, probability distributions of wind speeds...... probability, i.e. a study of the navigator's role in resolving critical situations, a causation factor is derived as a second step.The report documents the first step in a probabilistic collision damage analysis. Future work will inlcude calculation of energy released for crushing of structures giving...

  8. Estimating Subjective Probabilities

    DEFF Research Database (Denmark)

    Andersen, Steffen; Fountain, John; Harrison, Glenn W.

    2014-01-01

    either construct elicitation mechanisms that control for risk aversion, or construct elicitation mechanisms which undertake 'calibrating adjustments' to elicited reports. We illustrate how the joint estimation of risk attitudes and subjective probabilities can provide the calibration adjustments...... that theory calls for. We illustrate this approach using data from a controlled experiment with real monetary consequences to the subjects. This allows the observer to make inferences about the latent subjective probability, under virtually any well-specified model of choice under subjective risk, while still...

  9. Introduction to imprecise probabilities

    CERN Document Server

    Augustin, Thomas; de Cooman, Gert; Troffaes, Matthias C M

    2014-01-01

    In recent years, the theory has become widely accepted and has been further developed, but a detailed introduction is needed in order to make the material available and accessible to a wide audience. This will be the first book providing such an introduction, covering core theory and recent developments which can be applied to many application areas. All authors of individual chapters are leading researchers on the specific topics, assuring high quality and up-to-date contents. An Introduction to Imprecise Probabilities provides a comprehensive introduction to imprecise probabilities, includin

  10. Classic Problems of Probability

    CERN Document Server

    Gorroochurn, Prakash

    2012-01-01

    "A great book, one that I will certainly add to my personal library."—Paul J. Nahin, Professor Emeritus of Electrical Engineering, University of New Hampshire Classic Problems of Probability presents a lively account of the most intriguing aspects of statistics. The book features a large collection of more than thirty classic probability problems which have been carefully selected for their interesting history, the way they have shaped the field, and their counterintuitive nature. From Cardano's 1564 Games of Chance to Jacob Bernoulli's 1713 Golden Theorem to Parrondo's 1996 Perplexin

  11. Counterexamples in probability

    CERN Document Server

    Stoyanov, Jordan M

    2013-01-01

    While most mathematical examples illustrate the truth of a statement, counterexamples demonstrate a statement's falsity. Enjoyable topics of study, counterexamples are valuable tools for teaching and learning. The definitive book on the subject in regards to probability, this third edition features the author's revisions and corrections plus a substantial new appendix.

  12. Epistemology and Probability

    CERN Document Server

    Plotnitsky, Arkady

    2010-01-01

    Offers an exploration of the relationships between epistemology and probability in the work of Niels Bohr, Werner Heisenberg, and Erwin Schrodinger; in quantum mechanics; and in modern physics. This book considers the implications of these relationships and of quantum theory for our understanding of the nature of thinking and knowledge in general

  13. Transition probabilities for atoms

    International Nuclear Information System (INIS)

    Kim, Y.K.

    1980-01-01

    Current status of advanced theoretical methods for transition probabilities for atoms and ions is discussed. An experiment on the f values of the resonance transitions of the Kr and Xe isoelectronic sequences is suggested as a test for the theoretical methods

  14. Negative probability in the framework of combined probability

    OpenAIRE

    Burgin, Mark

    2013-01-01

    Negative probability has found diverse applications in theoretical physics. Thus, construction of sound and rigorous mathematical foundations for negative probability is important for physics. There are different axiomatizations of conventional probability. So, it is natural that negative probability also has different axiomatic frameworks. In the previous publications (Burgin, 2009; 2010), negative probability was mathematically formalized and rigorously interpreted in the context of extende...

  15. Contributions to quantum probability

    International Nuclear Information System (INIS)

    Fritz, Tobias

    2010-01-01

    Chapter 1: On the existence of quantum representations for two dichotomic measurements. Under which conditions do outcome probabilities of measurements possess a quantum-mechanical model? This kind of problem is solved here for the case of two dichotomic von Neumann measurements which can be applied repeatedly to a quantum system with trivial dynamics. The solution uses methods from the theory of operator algebras and the theory of moment problems. The ensuing conditions reveal surprisingly simple relations between certain quantum-mechanical probabilities. It also shown that generally, none of these relations holds in general probabilistic models. This result might facilitate further experimental discrimination between quantum mechanics and other general probabilistic theories. Chapter 2: Possibilistic Physics. I try to outline a framework for fundamental physics where the concept of probability gets replaced by the concept of possibility. Whereas a probabilistic theory assigns a state-dependent probability value to each outcome of each measurement, a possibilistic theory merely assigns one of the state-dependent labels ''possible to occur'' or ''impossible to occur'' to each outcome of each measurement. It is argued that Spekkens' combinatorial toy theory of quantum mechanics is inconsistent in a probabilistic framework, but can be regarded as possibilistic. Then, I introduce the concept of possibilistic local hidden variable models and derive a class of possibilistic Bell inequalities which are violated for the possibilistic Popescu-Rohrlich boxes. The chapter ends with a philosophical discussion on possibilistic vs. probabilistic. It can be argued that, due to better falsifiability properties, a possibilistic theory has higher predictive power than a probabilistic one. Chapter 3: The quantum region for von Neumann measurements with postselection. It is determined under which conditions a probability distribution on a finite set can occur as the outcome

  16. Bayesian Probability Theory

    Science.gov (United States)

    von der Linden, Wolfgang; Dose, Volker; von Toussaint, Udo

    2014-06-01

    Preface; Part I. Introduction: 1. The meaning of probability; 2. Basic definitions; 3. Bayesian inference; 4. Combinatrics; 5. Random walks; 6. Limit theorems; 7. Continuous distributions; 8. The central limit theorem; 9. Poisson processes and waiting times; Part II. Assigning Probabilities: 10. Transformation invariance; 11. Maximum entropy; 12. Qualified maximum entropy; 13. Global smoothness; Part III. Parameter Estimation: 14. Bayesian parameter estimation; 15. Frequentist parameter estimation; 16. The Cramer-Rao inequality; Part IV. Testing Hypotheses: 17. The Bayesian way; 18. The frequentist way; 19. Sampling distributions; 20. Bayesian vs frequentist hypothesis tests; Part V. Real World Applications: 21. Regression; 22. Inconsistent data; 23. Unrecognized signal contributions; 24. Change point problems; 25. Function estimation; 26. Integral equations; 27. Model selection; 28. Bayesian experimental design; Part VI. Probabilistic Numerical Techniques: 29. Numerical integration; 30. Monte Carlo methods; 31. Nested sampling; Appendixes; References; Index.

  17. Contributions to quantum probability

    Energy Technology Data Exchange (ETDEWEB)

    Fritz, Tobias

    2010-06-25

    Chapter 1: On the existence of quantum representations for two dichotomic measurements. Under which conditions do outcome probabilities of measurements possess a quantum-mechanical model? This kind of problem is solved here for the case of two dichotomic von Neumann measurements which can be applied repeatedly to a quantum system with trivial dynamics. The solution uses methods from the theory of operator algebras and the theory of moment problems. The ensuing conditions reveal surprisingly simple relations between certain quantum-mechanical probabilities. It also shown that generally, none of these relations holds in general probabilistic models. This result might facilitate further experimental discrimination between quantum mechanics and other general probabilistic theories. Chapter 2: Possibilistic Physics. I try to outline a framework for fundamental physics where the concept of probability gets replaced by the concept of possibility. Whereas a probabilistic theory assigns a state-dependent probability value to each outcome of each measurement, a possibilistic theory merely assigns one of the state-dependent labels ''possible to occur'' or ''impossible to occur'' to each outcome of each measurement. It is argued that Spekkens' combinatorial toy theory of quantum mechanics is inconsistent in a probabilistic framework, but can be regarded as possibilistic. Then, I introduce the concept of possibilistic local hidden variable models and derive a class of possibilistic Bell inequalities which are violated for the possibilistic Popescu-Rohrlich boxes. The chapter ends with a philosophical discussion on possibilistic vs. probabilistic. It can be argued that, due to better falsifiability properties, a possibilistic theory has higher predictive power than a probabilistic one. Chapter 3: The quantum region for von Neumann measurements with postselection. It is determined under which conditions a probability distribution on a

  18. Waste Package Misload Probability

    International Nuclear Information System (INIS)

    Knudsen, J.K.

    2001-01-01

    The objective of this calculation is to calculate the probability of occurrence for fuel assembly (FA) misloads (i.e., Fa placed in the wrong location) and FA damage during FA movements. The scope of this calculation is provided by the information obtained from the Framatome ANP 2001a report. The first step in this calculation is to categorize each fuel-handling events that occurred at nuclear power plants. The different categories are based on FAs being damaged or misloaded. The next step is to determine the total number of FAs involved in the event. Using the information, a probability of occurrence will be calculated for FA misload and FA damage events. This calculation is an expansion of preliminary work performed by Framatome ANP 2001a

  19. Probability theory and applications

    CERN Document Server

    Hsu, Elton P

    1999-01-01

    This volume, with contributions by leading experts in the field, is a collection of lecture notes of the six minicourses given at the IAS/Park City Summer Mathematics Institute. It introduces advanced graduates and researchers in probability theory to several of the currently active research areas in the field. Each course is self-contained with references and contains basic materials and recent results. Topics include interacting particle systems, percolation theory, analysis on path and loop spaces, and mathematical finance. The volume gives a balanced overview of the current status of probability theory. An extensive bibliography for further study and research is included. This unique collection presents several important areas of current research and a valuable survey reflecting the diversity of the field.

  20. Paradoxes in probability theory

    CERN Document Server

    Eckhardt, William

    2013-01-01

    Paradoxes provide a vehicle for exposing misinterpretations and misapplications of accepted principles. This book discusses seven paradoxes surrounding probability theory.  Some remain the focus of controversy; others have allegedly been solved, however the accepted solutions are demonstrably incorrect. Each paradox is shown to rest on one or more fallacies.  Instead of the esoteric, idiosyncratic, and untested methods that have been brought to bear on these problems, the book invokes uncontroversial probability principles, acceptable both to frequentists and subjectivists. The philosophical disputation inspired by these paradoxes is shown to be misguided and unnecessary; for instance, startling claims concerning human destiny and the nature of reality are directly related to fallacious reasoning in a betting paradox, and a problem analyzed in philosophy journals is resolved by means of a computer program.

  1. Measurement uncertainty and probability

    CERN Document Server

    Willink, Robin

    2013-01-01

    A measurement result is incomplete without a statement of its 'uncertainty' or 'margin of error'. But what does this statement actually tell us? By examining the practical meaning of probability, this book discusses what is meant by a '95 percent interval of measurement uncertainty', and how such an interval can be calculated. The book argues that the concept of an unknown 'target value' is essential if probability is to be used as a tool for evaluating measurement uncertainty. It uses statistical concepts, such as a conditional confidence interval, to present 'extended' classical methods for evaluating measurement uncertainty. The use of the Monte Carlo principle for the simulation of experiments is described. Useful for researchers and graduate students, the book also discusses other philosophies relating to the evaluation of measurement uncertainty. It employs clear notation and language to avoid the confusion that exists in this controversial field of science.

  2. Model uncertainty and probability

    International Nuclear Information System (INIS)

    Parry, G.W.

    1994-01-01

    This paper discusses the issue of model uncertainty. The use of probability as a measure of an analyst's uncertainty as well as a means of describing random processes has caused some confusion, even though the two uses are representing different types of uncertainty with respect to modeling a system. The importance of maintaining the distinction between the two types is illustrated with a simple example

  3. Retrocausality and conditional probability

    International Nuclear Information System (INIS)

    Stuart, C.I.J.M.

    1989-01-01

    Costa de Beauregard has proposed that physical causality be identified with conditional probability. The proposal is shown to be vulnerable on two accounts. The first, though mathematically trivial, seems to be decisive so far as the current formulation of the proposal is concerned. The second lies in a physical inconsistency which seems to have its source in a Copenhagenlike disavowal of realism in quantum mechanics. 6 refs. (Author)

  4. Probability via expectation

    CERN Document Server

    Whittle, Peter

    1992-01-01

    This book is a complete revision of the earlier work Probability which ap­ peared in 1970. While revised so radically and incorporating so much new material as to amount to a new text, it preserves both the aim and the approach of the original. That aim was stated as the provision of a 'first text in probability, de­ manding a reasonable but not extensive knowledge of mathematics, and taking the reader to what one might describe as a good intermediate level'. In doing so it attempted to break away from stereotyped applications, and consider applications of a more novel and significant character. The particular novelty of the approach was that expectation was taken as the prime concept, and the concept of expectation axiomatized rather than that of a probability measure. In the preface to the original text of 1970 (reproduced below, together with that to the Russian edition of 1982) I listed what I saw as the advantages of the approach in as unlaboured a fashion as I could. I also took the view that the text...

  5. Probability mapping of contaminants

    Energy Technology Data Exchange (ETDEWEB)

    Rautman, C.A.; Kaplan, P.G. [Sandia National Labs., Albuquerque, NM (United States); McGraw, M.A. [Univ. of California, Berkeley, CA (United States); Istok, J.D. [Oregon State Univ., Corvallis, OR (United States); Sigda, J.M. [New Mexico Inst. of Mining and Technology, Socorro, NM (United States)

    1994-04-01

    Exhaustive characterization of a contaminated site is a physical and practical impossibility. Descriptions of the nature, extent, and level of contamination, as well as decisions regarding proposed remediation activities, must be made in a state of uncertainty based upon limited physical sampling. The probability mapping approach illustrated in this paper appears to offer site operators a reasonable, quantitative methodology for many environmental remediation decisions and allows evaluation of the risk associated with those decisions. For example, output from this approach can be used in quantitative, cost-based decision models for evaluating possible site characterization and/or remediation plans, resulting in selection of the risk-adjusted, least-cost alternative. The methodology is completely general, and the techniques are applicable to a wide variety of environmental restoration projects. The probability-mapping approach is illustrated by application to a contaminated site at the former DOE Feed Materials Production Center near Fernald, Ohio. Soil geochemical data, collected as part of the Uranium-in-Soils Integrated Demonstration Project, have been used to construct a number of geostatistical simulations of potential contamination for parcels approximately the size of a selective remediation unit (the 3-m width of a bulldozer blade). Each such simulation accurately reflects the actual measured sample values, and reproduces the univariate statistics and spatial character of the extant data. Post-processing of a large number of these equally likely statistically similar images produces maps directly showing the probability of exceeding specified levels of contamination (potential clean-up or personnel-hazard thresholds).

  6. Probability mapping of contaminants

    International Nuclear Information System (INIS)

    Rautman, C.A.; Kaplan, P.G.; McGraw, M.A.; Istok, J.D.; Sigda, J.M.

    1994-01-01

    Exhaustive characterization of a contaminated site is a physical and practical impossibility. Descriptions of the nature, extent, and level of contamination, as well as decisions regarding proposed remediation activities, must be made in a state of uncertainty based upon limited physical sampling. The probability mapping approach illustrated in this paper appears to offer site operators a reasonable, quantitative methodology for many environmental remediation decisions and allows evaluation of the risk associated with those decisions. For example, output from this approach can be used in quantitative, cost-based decision models for evaluating possible site characterization and/or remediation plans, resulting in selection of the risk-adjusted, least-cost alternative. The methodology is completely general, and the techniques are applicable to a wide variety of environmental restoration projects. The probability-mapping approach is illustrated by application to a contaminated site at the former DOE Feed Materials Production Center near Fernald, Ohio. Soil geochemical data, collected as part of the Uranium-in-Soils Integrated Demonstration Project, have been used to construct a number of geostatistical simulations of potential contamination for parcels approximately the size of a selective remediation unit (the 3-m width of a bulldozer blade). Each such simulation accurately reflects the actual measured sample values, and reproduces the univariate statistics and spatial character of the extant data. Post-processing of a large number of these equally likely statistically similar images produces maps directly showing the probability of exceeding specified levels of contamination (potential clean-up or personnel-hazard thresholds)

  7. Probability of causation approach

    International Nuclear Information System (INIS)

    Jose, D.E.

    1988-01-01

    Probability of causation (PC) is sometimes viewed as a great improvement by those persons who are not happy with the present rulings of courts in radiation cases. The author does not share that hope and expects that PC will not play a significant role in these issues for at least the next decade. If it is ever adopted in a legislative compensation scheme, it will be used in a way that is unlikely to please most scientists. Consequently, PC is a false hope for radiation scientists, and its best contribution may well lie in some of the spin-off effects, such as an influence on medical practice

  8. Generalized Probability Functions

    Directory of Open Access Journals (Sweden)

    Alexandre Souto Martinez

    2009-01-01

    Full Text Available From the integration of nonsymmetrical hyperboles, a one-parameter generalization of the logarithmic function is obtained. Inverting this function, one obtains the generalized exponential function. Motivated by the mathematical curiosity, we show that these generalized functions are suitable to generalize some probability density functions (pdfs. A very reliable rank distribution can be conveniently described by the generalized exponential function. Finally, we turn the attention to the generalization of one- and two-tail stretched exponential functions. We obtain, as particular cases, the generalized error function, the Zipf-Mandelbrot pdf, the generalized Gaussian and Laplace pdf. Their cumulative functions and moments were also obtained analytically.

  9. Probability in High Dimension

    Science.gov (United States)

    2014-06-30

    precisely the content of the following result. The price we pay is that the assumption that A is a packing in (F, k ·k1) is too weak to make this happen...Regularité des trajectoires des fonctions aléatoires gaussiennes. In: École d’Été de Probabilités de Saint- Flour , IV-1974, pp. 1–96. Lecture Notes in...Lectures on probability theory and statistics (Saint- Flour , 1994), Lecture Notes in Math., vol. 1648, pp. 165–294. Springer, Berlin (1996) 50. Ledoux

  10. Flu Symptoms & Complications

    Science.gov (United States)

    ... Influenza Types Seasonal Avian Swine Variant Pandemic Other Flu Symptoms & Complications Language: English (US) Español Recommend on ... not everyone with flu will have a fever. Flu Complications Most people who get influenza will recover ...

  11. Pregnancy Complications: Shoulder Dystocia

    Science.gov (United States)

    ... Home > Complications & Loss > Pregnancy complications > Shoulder dystocia Shoulder dystocia Now playing: E-mail to a friend Please ... women more likely than others to have shoulder dystocia? A pregnant woman may be at risk for ...

  12. Complications and Deaths - State

    Data.gov (United States)

    U.S. Department of Health & Human Services — Complications and deaths - state data. This data set includes state-level data for the hip/knee complication measure, the Agency for Healthcare Research and Quality...

  13. Complications and Deaths - State

    Data.gov (United States)

    U.S. Department of Health & Human Services — Complications and deaths - state data. This data set includes state-level data for the hip/knee complication measure, the CMS Patient Safety Indicators, and 30-day...

  14. Skin Complications of IBD

    Science.gov (United States)

    ... Home > Resources > Skin Complications of IBD Go Back Skin Complications of IBD Email Print + Share After arthritis, ... about 5% of people with inflammatory bowel disease. SKIN DISORDERS COMMONLY SEEN IN IBD ERHTHEMA NODOSUM The ...

  15. Pregnancy Complications: Preeclampsia

    Science.gov (United States)

    ... online community Home > Complications & Loss > Pregnancy complications > Preeclampsia Preeclampsia E-mail to a friend Please fill in ... even if you’re feeling fine. What is preeclampsia? Preeclampsia is a serious blood pressure condition that ...

  16. Pregnancy Complications: Anemia

    Science.gov (United States)

    ... online community Home > Complications & Loss > Pregnancy complications > Anemia Anemia E-mail to a friend Please fill in ... anemia at a prenatal care visit . What causes anemia? Usually, a woman becomes anemic (has anemia) because ...

  17. Complications and Deaths - Hospital

    Data.gov (United States)

    U.S. Department of Health & Human Services — Complications and deaths - provider data. This data set includes provider data for the hip/knee complication measure, CMS Patient Safety Indicators of serious...

  18. Complications and Deaths - National

    Data.gov (United States)

    U.S. Department of Health & Human Services — Complications and deaths - national data. This data set includes national-level data for the hip/knee complication measure, the CMS Patient Safety Indicators, and...

  19. Probable maximum flood control

    International Nuclear Information System (INIS)

    DeGabriele, C.E.; Wu, C.L.

    1991-11-01

    This study proposes preliminary design concepts to protect the waste-handling facilities and all shaft and ramp entries to the underground from the probable maximum flood (PMF) in the current design configuration for the proposed Nevada Nuclear Waste Storage Investigation (NNWSI) repository protection provisions were furnished by the United States Bureau of Reclamation (USSR) or developed from USSR data. Proposed flood protection provisions include site grading, drainage channels, and diversion dikes. Figures are provided to show these proposed flood protection provisions at each area investigated. These areas are the central surface facilities (including the waste-handling building and waste treatment building), tuff ramp portal, waste ramp portal, men-and-materials shaft, emplacement exhaust shaft, and exploratory shafts facility

  20. Complicated Horseshoe Kidney

    Energy Technology Data Exchange (ETDEWEB)

    Kim, K. S.; Kim, S. R.; Cha, K. S.; Park, S. S. [Chung Ang University College of Medicine, Seoul (Korea, Republic of)

    2010-05-15

    Horseshoe kidney is an important urological anomaly when it is complicated or accompanied by other diseases. Recently we have experienced four cases of horseshoe kidney which were complicated with hydronephrosis, renal stone and adrenal pheochromocytoma. With review of literatures, we emphasize the importance of detection of these complications.

  1. Complicated Horseshoe Kidney

    International Nuclear Information System (INIS)

    Kim, K. S.; Kim, S. R.; Cha, K. S.; Park, S. S.

    2010-01-01

    Horseshoe kidney is an important urological anomaly when it is complicated or accompanied by other diseases. Recently we have experienced four cases of horseshoe kidney which were complicated with hydronephrosis, renal stone and adrenal pheochromocytoma. With review of literatures, we emphasize the importance of detection of these complications.

  2. A method of analyzing rectal surface area irradiated and rectal complications in prostate conformal radiotherapy

    International Nuclear Information System (INIS)

    Lu Yong; Song, Paul Y.; Li Shidong; Spelbring, Danny R.; Vijayakumar, Srinivasan; Haraf, Daniel J.; Chen, George T.Y.

    1995-01-01

    Purpose: To develop a method of analyzing rectal surface area irradiated and rectal complications in prostate conformal radiotherapy. Methods and Materials: Dose-surface histograms of the rectum, which state the rectal surface area irradiated to any given dose, were calculated for a group of 27 patients treated with a four-field box technique to a total (tumor minimum) dose ranging from 68 to 70 Gy. Occurrences of rectal toxicities as defined by the Radiation Therapy Oncology Group (RTOG) were recorded and examined in terms of dose and rectal surface area irradiated. For a specified end point of rectal complication, the complication probability was analyzed as a function of dose irradiated to a fixed rectal area, and as a function of area receiving a fixed dose. Lyman's model of normal tissue complication probability (NTCP) was used to fit the data. Results: The observed occurrences of rectal complications appear to depend on the rectal surface area irradiated to a given dose level. The patient distribution of each toxicity grade exhibits a maximum as a function of percentage surface area irradiated, and the maximum moves to higher values of percentage surface area as the toxicity grade increases. The dependence of the NTCP for the specified end point on dose and percentage surface area irradiated was fitted to Lyman's NTCP model with a set of parameters. The curvature of the NTCP as a function of the surface area suggests that the rectum is a parallel structured organ. Conclusions: The described method of analyzing rectal surface area irradiated yields interesting insight into understanding rectal complications in prostate conformal radiotherapy. Application of the method to a larger patient data set has the potential to facilitate the construction of a full dose-surface-complication relationship, which would be most useful in guiding clinical practice

  3. The profile of potential organ and tissue donors El perfil de probables donadores de órganos y tejidos O perfil de potenciais doadores de órgãos e tecidos

    Directory of Open Access Journals (Sweden)

    Edvaldo Leal de Moraes

    2009-10-01

    Full Text Available This study aimed to characterize donors according to gender, age group, cause of brain death; quantify donors with hypernatremia, hyperpotassemia and hypopotassemia; and get to know which organs were the most used in transplantations. This quantitative, descriptive, exploratory and retrospective study was performed at the Organ Procurement Organization of the University of São Paulo Medical School Hospital das Clínicas. Data from the medical records of 187 potential donors were analyzed. Cerebrovascular accidents represented 53.48% of all brain death causes, sodium and potassium disorders occurred in 82.36% of cases and 45.46% of the potential donors were between 41 and 60 years old. The results evidenced that natural death causes exceeded traumatic deaths, and that most donors presented sodium and potassium alterations, likely associated to inappropriate maintenance.Se tuvo como objetivos determinar las características de los donadores según el sexo, el intervalo de edad, y, las causas por muerte encefálica; determinar el número donadores que presentaban hipernatremia, hiperpotasemia y hipopotasemia; conocer los órganos que fueron más utilizados para el trasplante. Es un estudio de tipo cuantitativo, descriptivo, exploratorio y retrospectivo. La investigación fue realizada en una Institución de donación de Órganos perteneciente al Hospital de las Clínicas de Sao Paulo. Fueron analizados los datos de 187 probables donadores. Entre las causas de muerte encefálica el 53,48% fueron por accidente cerebro vascular, en 82,36% de los casos se produjeron alteraciones en los valores de sodio y potasio y los donadores se encontraban entre 41 y 60 años de edad. Los resultados muestran que las causas naturales de muerte superaron a las muertes por traumatismo. La mayoría de los donadores tuvo alteraciones en los niveles de sodio y potasio, estando posiblemente relacionadas a medidas de conservación inadecuadas.Objetivou-se caracterizar os

  4. Metabolic complications in oncology

    International Nuclear Information System (INIS)

    Sycova-Mila, Z.

    2012-01-01

    Currently, a lot of space and time is devoted to the therapy of oncologic diseases itself. To reach the good therapy results, complex care of the oncologic patient is needed. Management of complications linked with the disease itself and management of complications emerged after administration of chemotherapy, radiotherapy or targeted therapy, plays a significant role. In addition to infectious, hematological, neurological, cardiac or other complications, metabolic complications are relatively extensive and serious. One of the most frequent metabolic complications in oncology is tumor lysis syndrome, hyperuricemia, hypercalcaemia and syndrome of inappropriate secretion of antidiuretic hormone. (author)

  5. Complications of wrist arthroscopy.

    Science.gov (United States)

    Ahsan, Zahab S; Yao, Jeffrey

    2012-06-01

    The purpose of this systematic review was to address the incidence of complications associated with wrist arthroscopy. Given the paucity of information published on this topic, an all-inclusive review of published wrist arthroscopy complications was sought. Two independent reviewers performed a literature search using PubMed, Google Scholar, EBSCO, and Academic Megasearch using the terms "wrist arthroscopy complications," "complications of wrist arthroscopy," "wrist arthroscopy injury," and "wrist arthroscopy." Inclusion criteria were (1) Levels I to V evidence, (2) "complication" defined as an adverse outcome directly related to the operative procedure, and (3) explicit description of operative complications in the study. Eleven multiple-patient studies addressing complications of wrist arthroscopy from 1994 to 2010 were identified, with 42 complications reported from 895 wrist arthroscopy procedures, a 4.7% complication rate. Four case reports were also found, identifying injury to the dorsal sensory branch of the ulnar nerve, injury to the posterior interosseous nerve, and extensor tendon sheath fistula formation. This systematic review suggests that the previously documented rate of wrist arthroscopy complications may be underestimating the true incidence. The report of various complications provides insight to surgeons for improving future surgical techniques. Level IV, systematic review of Levels I-V studies. Copyright © 2012 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  6. Dose-volume complication analysis for visual pathway structures of patients with advanced paranasal sinus tumors

    International Nuclear Information System (INIS)

    Martel, Mary Kaye; Sandler, Howard M.; Cornblath, Wayne T.; Marsh, Lon H.; Hazuka, Mark B.; Roa, Wilson H.; Fraass, Benedict A.; Lichter, Allen S.

    1997-01-01

    Purpose: The purpose of the present work was to relate dose and volume information to complication data for visual pathway structures in patients with advanced paranasal sinus tumors. Methods and Materials: Three-dimensional (3D) dose distributions for chiasm, optic nerve, and retina were calculated and analyzed for 20 patients with advanced paranasal sinus malignant tumors. 3D treatment planning with beam's eye view capability was used to design beam and block arrangements, striving to spare the contralateral orbit (to lessen the chance of unilateral blindness) and frequently the ipsilateral orbit (to help prevent bilateral blindness). Point doses, dose-volume histogram analysis, and normal tissue complication probability (NTCP) calculations were performed. Published tolerance doses that indicate significant risk of complications were used as guidelines for analysis of the 3D dose distributions. Results: Point doses, percent volume exceeding a specified published tolerance dose, and NTCP calculations are given in detail for patients with complications versus patients without complications. Two optic nerves receiving maximum doses below the published tolerance dose sustained damage (mild vision loss). Three patients (of 13) without optic nerve sparing and/or chiasm sparing had moderate or severe vision loss. Complication data, including individual patient analysis to estimate overall risk for loss of vision, are given. Conclusion: 3D treatment planning techniques were used successfully to provide bilateral sparing of the globe for most patients. It was more difficult to spare the optic nerves, especially on the ipsilateral side, when prescription dose exceeded the normal tissue tolerance doses. NTCP calculations may be useful in assessing complication risk better than point dose tolerance criteria for the chiasm, optic nerve, and retina. It is important to assess the overall risk of blindness for the patient in addition to the risk for individual visual pathway

  7. Probability and rational choice

    Directory of Open Access Journals (Sweden)

    David Botting

    2014-05-01

    Full Text Available http://dx.doi.org/10.5007/1808-1711.2014v18n1p1 In this paper I will discuss the rationality of reasoning about the future. There are two things that we might like to know about the future: which hypotheses are true and what will happen next. To put it in philosophical language, I aim to show that there are methods by which inferring to a generalization (selecting a hypothesis and inferring to the next instance (singular predictive inference can be shown to be normative and the method itself shown to be rational, where this is due in part to being based on evidence (although not in the same way and in part on a prior rational choice. I will also argue that these two inferences have been confused, being distinct not only conceptually (as nobody disputes but also in their results (the value given to the probability of the hypothesis being not in general that given to the next instance and that methods that are adequate for one are not by themselves adequate for the other. A number of debates over method founder on this confusion and do not show what the debaters think they show.

  8. COVAL, Compound Probability Distribution for Function of Probability Distribution

    International Nuclear Information System (INIS)

    Astolfi, M.; Elbaz, J.

    1979-01-01

    1 - Nature of the physical problem solved: Computation of the probability distribution of a function of variables, given the probability distribution of the variables themselves. 'COVAL' has been applied to reliability analysis of a structure subject to random loads. 2 - Method of solution: Numerical transformation of probability distributions

  9. Thoracic complications of rheumatoid disease

    International Nuclear Information System (INIS)

    Massey, H.; Darby, M.; Edey, A.

    2013-01-01

    Rheumatoid arthritis is a relatively common multisystem disease associated with significant mortality and morbidity. Thoracic disease, both pleural and pulmonary, is a frequent extra-articular manifestation of rheumatoid arthritis and responsible for approximately 20% of rheumatoid-associated mortality. Rheumatoid disease and its associated therapies can affect all compartments of the lung inciting a range of stereotyped pathological responses and it is not infrequent for multiple disease entities to co-exist. In some instances, development of pulmonary complications may precede typical rheumatological presentation of the disease and be the first indication of an underlying connective tissue disease. The spectrum of thoracic disease related to rheumatoid arthritis is reviewed

  10. Complications of surgery for radiotherapy skin damage

    International Nuclear Information System (INIS)

    Rudolph, R.

    1982-01-01

    Complications of modern surgery for radiotherapy skin damage reviewed in 28 patients who had 42 operations. Thin split-thickness skin grafts for ulcer treatment had a 100 percent complication rate, defined as the need for further surgery. Local flaps, whether delayed or not, also had a high rate of complications. Myocutaneous flaps for ulcers had a 43 percent complication rate, with viable flaps lifting off radiated wound beds. Only myocutaneous flaps for breast reconstruction and omental flaps with skin grafts and Marlex mesh had no complications. The deeper tissue penetration of modern radiotherapy techniques may make skin grafts and flaps less useful. In reconstruction of radiation ulcers, omental flaps and myocutaneous flaps are especially useful, particularly if the radiation damage can be fully excised. The pull of gravity appears detrimental to myocutaneous flap healing and, if possible, should be avoided by flap design

  11. A Tale of Two Probabilities

    Science.gov (United States)

    Falk, Ruma; Kendig, Keith

    2013-01-01

    Two contestants debate the notorious probability problem of the sex of the second child. The conclusions boil down to explication of the underlying scenarios and assumptions. Basic principles of probability theory are highlighted.

  12. Introduction to probability with R

    CERN Document Server

    Baclawski, Kenneth

    2008-01-01

    FOREWORD PREFACE Sets, Events, and Probability The Algebra of Sets The Bernoulli Sample Space The Algebra of Multisets The Concept of Probability Properties of Probability Measures Independent Events The Bernoulli Process The R Language Finite Processes The Basic Models Counting Rules Computing Factorials The Second Rule of Counting Computing Probabilities Discrete Random Variables The Bernoulli Process: Tossing a Coin The Bernoulli Process: Random Walk Independence and Joint Distributions Expectations The Inclusion-Exclusion Principle General Random Variable

  13. Cardiovascular complications of cirrhosis

    DEFF Research Database (Denmark)

    Møller, S; Henriksen, Jens Henrik Sahl

    2008-01-01

    Cardiovascular complications of cirrhosis include cardiac dysfunction and abnormalities in the central, splanchnic and peripheral circulation, and haemodynamic changes caused by humoral and nervous dysregulation. Cirrhotic cardiomyopathy implies systolic and diastolic dysfunction and electrophysi......Cardiovascular complications of cirrhosis include cardiac dysfunction and abnormalities in the central, splanchnic and peripheral circulation, and haemodynamic changes caused by humoral and nervous dysregulation. Cirrhotic cardiomyopathy implies systolic and diastolic dysfunction....... The clinical significance of cardiovascular complications and cirrhotic cardiomyopathy is an important topic for future research, and the initiation of new randomised studies of potential treatments for these complications is needed....

  14. Complications of mechanical ventilation

    Directory of Open Access Journals (Sweden)

    Drašković Biljana

    2011-01-01

    Full Text Available Mechanical ventilation of the lungs, as an important therapeutic measure, cannot be avoided in critically ill patients. However, when machines take over some of vital functions there is always a risk of complications and accidents. Complications associated with mechanical ventilation can be divided into: 1 airway-associated complications; 2 complications in the response of patients to mechanical ventilation; and 3 complications related to the patient’s response to the device for mechanical ventilation. Complications of artificial airway may be related to intubation and extubation or the endotracheal tube. Complications of mechanical ventilation, which arise because of the patient’s response to mechanical ventilation, may primarily cause significant side effects to the lungs. During the last two decades it was concluded that mechanical ventilation can worsen or cause acute lung injury. Mechanical ventilation may increase the alveolar/capillary permeability by overdistension of the lungs (volutrauma, it can exacerbate lung damage due to the recruitment/derecruitment of collapsed alveoli (atelectrauma and may cause subtle damages due to the activation of inflammatory processes (biotrauma. Complications caused by mechanical ventilation, beside those involving the lungs, can also have significant effects on other organs and organic systems, and can be a significant factor contributing to the increase of morbidity and mortality in critically ill of mechanically ventilated patients. Complications are fortunately rare and do not occur in every patient, but due to their seriousness and severity they require extensive knowledge, experience and responsibility by health-care workers.

  15. A first course in probability

    CERN Document Server

    Ross, Sheldon

    2014-01-01

    A First Course in Probability, Ninth Edition, features clear and intuitive explanations of the mathematics of probability theory, outstanding problem sets, and a variety of diverse examples and applications. This book is ideal for an upper-level undergraduate or graduate level introduction to probability for math, science, engineering and business students. It assumes a background in elementary calculus.

  16. Dosimetric precision requirements and quantities for characterizing the response of tumors and normal tissues

    Energy Technology Data Exchange (ETDEWEB)

    Brahme, A [Karolinska Inst., Stockholm (Sweden). Dept. of Radiation Physics

    1996-08-01

    Based on simple radiobiological models the effect of the distribution of absorbed dose in therapy beams on the radiation response of tumor and normal tissue volumes are investigated. Under the assumption that the dose variation in the treated volume is small it is shown that the response of the tissue to radiation is determined mainly by the mean dose to the tumor or normal tissue volume in question. Quantitative expressions are also given for the increased probability of normal tissue complications and the decreased probability of tumor control as a function of increasing dose variations around the mean dose level to these tissues. When the dose variations are large the minimum tumor dose (to cm{sup 3} size volumes) will generally be better related to tumor control and the highest dose to significant portions of normal tissue correlates best to complications. In order not to lose more than one out of 20 curable patients (95% of highest possible treatment outcome) the required accuracy in the dose distribution delivered to the target volume should be 2.5% (1{sigma}) for a mean dose response gradient {gamma} in the range 2 - 3. For more steeply responding tumors and normal tissues even stricter requirements may be desirable. (author). 15 refs, 6 figs.

  17. A brief introduction to probability.

    Science.gov (United States)

    Di Paola, Gioacchino; Bertani, Alessandro; De Monte, Lavinia; Tuzzolino, Fabio

    2018-02-01

    The theory of probability has been debated for centuries: back in 1600, French mathematics used the rules of probability to place and win bets. Subsequently, the knowledge of probability has significantly evolved and is now an essential tool for statistics. In this paper, the basic theoretical principles of probability will be reviewed, with the aim of facilitating the comprehension of statistical inference. After a brief general introduction on probability, we will review the concept of the "probability distribution" that is a function providing the probabilities of occurrence of different possible outcomes of a categorical or continuous variable. Specific attention will be focused on normal distribution that is the most relevant distribution applied to statistical analysis.

  18. Probable functions of calcium oxalate crystals in different tissues of ...

    African Journals Online (AJOL)

    Representatives of seven major edible aroid accessions were screened for calcium oxalate using standard histochemical methods. All the accessions were noted to contain calcium oxalate in the forms of raphide bundles and intra-amylar crystals. The crystals were widely present in all parts of the plants including spongy ...

  19. Sinogenic intracranial complications

    DEFF Research Database (Denmark)

    Kofoed, Mikkel Seremet; Fisker, Niels; Christensen, Anne Estmann

    2018-01-01

    We present two 11-year-old girls with chronic recurrent multifocal osteomyelitis, treated with adalimumab. Both developed severe intracranial complications to sinusitis. Patient 1 had been treated with adalimumab for 15 months when she developed acute sinusitis complicated by an orbital abscess, ...

  20. [Complications in pediatric anesthesia].

    Science.gov (United States)

    Becke, K

    2014-07-01

    As in adult anesthesia, morbidity and mortality could be significantly reduced in pediatric anesthesia in recent decades. This fact cannot conceal the fact that the incidence of anesthetic complications in children is still much more common than in adults and sometimes with a severe outcome. Newborns and infants in particular but also children with emergency interventions and severe comorbidities are at increased risk of potential complications. Typical complications in pediatric anesthesia are respiratory problems, medication errors, difficulties with the intravenous puncture and pulmonal aspiration. In the postoperative setting, nausea and vomiting, pain, and emergence delirium can be mentioned as typical complications. In addition to the systematic prevention of complications in pediatric anesthesia, it is important to quickly recognize disturbances of homeostasis and treat them promptly and appropriately. In addition to the expertise of the performing anesthesia team, the institutional structure in particular can improve quality and safety in pediatric anesthesia.

  1. Oral piercings: immediate and late complications.

    Science.gov (United States)

    Vieira, Elma P; Ribeiro, Andre Luis Ribeiro; Pinheiro, João de Jesus V; Alves, Sérgio de M

    2011-12-01

    Oral piercings have a long history as part of religious, cultural, or sexual symbolism in many traditional tribes; currently, these ornaments have wide acceptance among young people. Several oral and systemic complications may be associated with this practice; however, limited data related to these complications can be obtained in the literature. This study includes 42 cases of oral piercings in 39 young adults, who were using or had used oral piercings, and the complications associated with their use. Immediate complications occurred in 29 cases, including excessive bleeding (69%) and pain (52.3%) as the most representative. Two cases of syncope were found. Late complications related to the piercing insertion site were observed in 97.6% of cases, with pain and swelling being present in 92.9% and 61.9% of cases, respectively. Dental pain and lacerations on the tongue represented the most prevalent complications associated with the surrounding tissues, accounting for 33.3% and 31% of cases. The use of oral piercings is related to a series of mainly local complications, and individuals who decide to use piercings should be aware of such complications. Individuals wishing to get a part of their body pierced should do so with qualified professionals and should regularly visit the dentist so that a regular control is achieved, thus ensuring the early detection of the adverse effects associated with this practice. Copyright © 2011 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  2. Microdebrider complications in laryngologic and airway surgery.

    Science.gov (United States)

    Howell, Rebecca J; Solowski, Nancy L; Belafsky, Peter C; Courey, Mark C; Merati, Albert L; Rosen, Clark A; Weinberger, Paul M; Postma, Gregory N

    2014-11-01

    There is a paucity of experience in the published literature documenting complications of powered surgical instruments in laryngologic surgery. Our objective was to ascertain the nature of these complications from expert opinion and review of the literature, and to recommend strategies to decrease major complications. Review of the literature and an e-mail survey. A literature review of microdebrider complications in laryngologic surgery was conducted using PubMed and Ovid (1985 to 2013), along with an analysis of a confidential e-mail survey of various surgeons in selected high-volume laryngologic centers. Powered instrumentation is frequently used in the operating room for larynx and airway surgery. The microdebrider can improve efficiency, lower costs, and shorten operative times. However, use of the microdebrider has the potential for serious complications in the larynx and airway. Great care must be taken when utilizing the microdebrider in laryngologic surgery. Significant complications including major vocal fold scar, airway compromise, severe hemorrhage, and unintentional tissue loss have occurred. The microdebrider is a popular and valuable tool for the otolaryngologist. A thorough knowledge of the instrument and its potential complications will improve surgical outcomes and may prevent complications. Awareness of the risks and surgeon experience with use of the microdebrider will allow the surgeon to successfully utilize this device in a safe and effective manner. 5. © 2014 The American Laryngological, Rhinological and Otological Society, Inc.

  3. Propensity, Probability, and Quantum Theory

    Science.gov (United States)

    Ballentine, Leslie E.

    2016-08-01

    Quantum mechanics and probability theory share one peculiarity. Both have well established mathematical formalisms, yet both are subject to controversy about the meaning and interpretation of their basic concepts. Since probability plays a fundamental role in QM, the conceptual problems of one theory can affect the other. We first classify the interpretations of probability into three major classes: (a) inferential probability, (b) ensemble probability, and (c) propensity. Class (a) is the basis of inductive logic; (b) deals with the frequencies of events in repeatable experiments; (c) describes a form of causality that is weaker than determinism. An important, but neglected, paper by P. Humphreys demonstrated that propensity must differ mathematically, as well as conceptually, from probability, but he did not develop a theory of propensity. Such a theory is developed in this paper. Propensity theory shares many, but not all, of the axioms of probability theory. As a consequence, propensity supports the Law of Large Numbers from probability theory, but does not support Bayes theorem. Although there are particular problems within QM to which any of the classes of probability may be applied, it is argued that the intrinsic quantum probabilities (calculated from a state vector or density matrix) are most naturally interpreted as quantum propensities. This does not alter the familiar statistical interpretation of QM. But the interpretation of quantum states as representing knowledge is untenable. Examples show that a density matrix fails to represent knowledge.

  4. [Surgical complications of colostomies].

    Science.gov (United States)

    Ben Ameur, Hazem; Affes, Nejmeddine; Rejab, Haitham; Abid, Bassem; Boujelbene, Salah; Mzali, Rafik; Beyrouti, Mohamed Issam

    2014-07-01

    The colostomy may be terminal or lateral, temporary or permanent. It may have psychological, medical or surgical complications. reporting the incidence of surgical complications of colostomies, their therapeutic management and trying to identify risk factors for their occurrence. A retrospective study for a period of 5 years in general surgery department, Habib Bourguiba hospital, Sfax, including all patients operated with confection of a colostomy. Were then studied patients reoperated for stoma complication. Among the 268 patients who have had a colostomy, 19 patients (7%) developed surgical stoma complications. They had a mean age of 59 years, a sex ratio of 5.3 and a 1-ASA score in 42% of cases. It was a prolapse in 9 cases (reconfection of the colostomy: 6 cases, restoration of digestive continuity: 3 cases), a necrosis in 5 cases (reconfection of the colostomy), a plicature in 2 cases (reconfection of the colostomy) a peristomal abscess in 2 cases (reconfection of the colostomy: 1 case, restoration of digestive continuity: 1 case) and a strangulated parastomal hernia in 1 case (herniorrhaphy). The elective incision and the perineal disease were risk factors for the occurrence of prolapse stomial. Surgical complications of colostomies remain a rare event. Prolapse is the most common complication, and it is mainly related to elective approach. Reoperation is often required especially in cases of early complications, with usually uneventful postoperative course.

  5. Prediction and probability in sciences

    International Nuclear Information System (INIS)

    Klein, E.; Sacquin, Y.

    1998-01-01

    This book reports the 7 presentations made at the third meeting 'physics and fundamental questions' whose theme was probability and prediction. The concept of probability that was invented to apprehend random phenomena has become an important branch of mathematics and its application range spreads from radioactivity to species evolution via cosmology or the management of very weak risks. The notion of probability is the basis of quantum mechanics and then is bound to the very nature of matter. The 7 topics are: - radioactivity and probability, - statistical and quantum fluctuations, - quantum mechanics as a generalized probability theory, - probability and the irrational efficiency of mathematics, - can we foresee the future of the universe?, - chance, eventuality and necessity in biology, - how to manage weak risks? (A.C.)

  6. Applied probability and stochastic processes

    CERN Document Server

    Sumita, Ushio

    1999-01-01

    Applied Probability and Stochastic Processes is an edited work written in honor of Julien Keilson. This volume has attracted a host of scholars in applied probability, who have made major contributions to the field, and have written survey and state-of-the-art papers on a variety of applied probability topics, including, but not limited to: perturbation method, time reversible Markov chains, Poisson processes, Brownian techniques, Bayesian probability, optimal quality control, Markov decision processes, random matrices, queueing theory and a variety of applications of stochastic processes. The book has a mixture of theoretical, algorithmic, and application chapters providing examples of the cutting-edge work that Professor Keilson has done or influenced over the course of his highly-productive and energetic career in applied probability and stochastic processes. The book will be of interest to academic researchers, students, and industrial practitioners who seek to use the mathematics of applied probability i...

  7. Imaging of osteochondroma complications

    International Nuclear Information System (INIS)

    Gomes, Fernando Santos Emerich; Lewin, Fabio; Mariotti, Guilherme Cayres; Capasso Filho, Mauro; Yamaguchi, Claudia Kazue; Cruz, Rafael O.; Baptista, Pedro Pericles Ribeiro; Yonamine, Eduardo Sadao; Prospero, Jose Donato

    2007-01-01

    Osteochondroma is the most common entity beyond all the known osseous tumors. It is a lesion with a high enlargement capacity and a continuous growing in some cases, and it may determine complications, mainly due to mass effect. It may be present in a solitary or multiple forms, and the last one is related with a higher tendency to sarcomatous transformation, which is the most frightening complication. The purpose of the present study is to demonstrate, through an iconographic assay, the most common complications caused by the osteochondromas, making the correlation of its clinical and radiological aspects. (author)

  8. Poisson Processes in Free Probability

    OpenAIRE

    An, Guimei; Gao, Mingchu

    2015-01-01

    We prove a multidimensional Poisson limit theorem in free probability, and define joint free Poisson distributions in a non-commutative probability space. We define (compound) free Poisson process explicitly, similar to the definitions of (compound) Poisson processes in classical probability. We proved that the sum of finitely many freely independent compound free Poisson processes is a compound free Poisson processes. We give a step by step procedure for constructing a (compound) free Poisso...

  9. PROBABILITY SURVEYS , CONDITIONAL PROBABILITIES AND ECOLOGICAL RISK ASSESSMENT

    Science.gov (United States)

    We show that probability-based environmental resource monitoring programs, such as the U.S. Environmental Protection Agency's (U.S. EPA) Environmental Monitoring and Assessment Program, and conditional probability analysis can serve as a basis for estimating ecological risk over ...

  10. Correlates of time to microvascular complications among diabetes ...

    African Journals Online (AJOL)

    Socio-demographic and clinical factors have been known to affect the time to microvascular complications and survival probabilities of diabetes mellitus patients. The objective of this study was to identify risk factors and estimate average survival times for the time to the development of microvascular complications of ...

  11. ORO dental complications of radiotherapy

    International Nuclear Information System (INIS)

    Kaumuri, Sunil

    2014-01-01

    Radiation and radioactivity were discovered more than 100 years ago. Since then, radiation has become important in cancer treatment. Approximately one million people will develop invasive cancer each year. Of these, 40% will receive curative benefit from surgery, radiation, chemotherapy, or a combination modality. Normal body tissues vary in their response to radiation. As with tumors, normal tissues in which cells are quickly dividing may be affected. This causes some of the side effects of radiation treatment. Since radiation is a local treatment, side effects depend on the area of the body being treated. The early effects of radiation may be seen a few days or weeks after treatments have started and may go on for several weeks after treatments have ended. Other effects may not show up until months, or even years, later. As radiotherapy is a viable treatment modality for head and neck cancer, however a wide range of potentially debilitating dental complications may accompany this treatment. The orofacial tissues of dental significance that may be affected by head and neck radiotherapy are the salivary glands, mucous membranes, taste buds, bone and teeth. (author)

  12. Postoperative rectal anastomotic complications

    Czech Academy of Sciences Publication Activity Database

    Polanecký, O.; Adámek, S.; Šedý, Jiří; Skořepa, J.; Hladík, P.; Šmejkal, M.; Pafko, P.; Lischke, R.

    2014-01-01

    Roč. 115, č. 12 (2014), s. 781-785 ISSN 0006-9248 Institutional support: RVO:67985823 Keywords : human * complication * anastomosis * rectum Subject RIV: FJ - Surgery incl. Transplants Impact factor: 0.439, year: 2014

  13. Complications of Circumcision

    Directory of Open Access Journals (Sweden)

    Aaron J. Krill

    2011-01-01

    Full Text Available In the United States, circumcision is a commonly performed procedure. It is a relatively safe procedure with a low overall complication rate. Most complications are minor and can be managed easily. Though uncommon, complications of circumcision do represent a significant percentage of cases seen by pediatric urologists. Often they require surgical correction that results in a significant cost to the health care system. Severe complications are quite rare, but death has been reported as a result in some cases. A thorough and complete preoperative evaluation, focusing on bleeding history and birth history, is imperative. Proper selection of patients based on age and anatomic considerations as well as proper sterile surgical technique are critical to prevent future circumcision-related adverse events.

  14. Complications of shoulder dystocia.

    Science.gov (United States)

    Dajani, Nafisa K; Magann, Everett F

    2014-06-01

    Complications of shoulder dystocia are divided into fetal and maternal. Fetal brachial plexus injury (BPI) is the most common fetal complication occurring in 4-40% of cases. BPI has also been reported in abdominal deliveries and in deliveries not complicated by shoulder dystocia. Fractures of the fetal humerus and clavicle occur in about 10.6% of cases of shoulder dystocia and usually heal with no sequel. Hypoxic ischemic brain injury is reported in 0.5-23% of cases of shoulder dystocia. The risk correlates with the duration of head-to-body delivery and is especially increased when the duration is >5 min. Fetal death is rare and is reported in 0.4% of cases. Maternal complications of shoulder dystocia include post-partum hemorrhage, vaginal lacerations, anal tears, and uterine rupture. The psychological stress impact of shoulder dystocia is under-recognized and deserves counseling prior to home discharge. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Pertussis (Whooping Cough) Complications

    Science.gov (United States)

    ... of Search Controls Search Form Controls Cancel Submit Pertussis (Whooping Cough) Note: Javascript is disabled or is not supported ... message, please visit this page: About CDC.gov . Pertussis Home About Pertussis Causes & Transmission Signs & Symptoms Complications ...

  16. The collision probability modules of WIMS-E

    International Nuclear Information System (INIS)

    Roth, M.J.

    1985-04-01

    This report describes how flat source first flight collision probabilities are calculated and used in the WIMS-E modular program. It includes a description of the input to the modules W-FLU, W-THES, W-PIP, W-PERS and W-MERGE. Input to other collision probability modules are described in separate reports. WIMS-E is capable of calculating collision probabilities in a wide variety of geometries, some of them quite complicated. It can also use them for a variety of purposes. (author)

  17. Management of complications of mesh surgery.

    Science.gov (United States)

    Lee, Dominic; Zimmern, Philippe E

    2015-07-01

    Transvaginal placements of synthetic mid-urethral slings and vaginal meshes have largely superseded traditional tissue repairs in the current era because of presumed efficacy and ease of implant with device 'kits'. The use of synthetic material has generated novel complications including mesh extrusion, pelvic and vaginal pain and mesh contraction. In this review, our aim is to discuss the management, surgical techniques and outcomes associated with mesh removal. Recent publications have seen an increase in presentation of these mesh-related complications, and reports from multiple tertiary centers have suggested that not all patients benefit from surgical intervention. Although the true incidence of mesh complications is unknown, recent publications can serve to guide physicians and inform patients of the surgical outcomes from mesh-related complications. In addition, the literature highlights the growing need for a registry to account for a more accurate reporting of these events and to counsel patients on the risk and benefits before proceeding with mesh surgeries.

  18. Neurologic complications in oncology

    Directory of Open Access Journals (Sweden)

    Andrea Pace

    2010-06-01

    Full Text Available Neurologic side effects related to cancer therapy are a common problem in oncology practice. These complications can negatively affect the management of the patient, because they can inhibit treatment and diminish quality of life. Therefore specific skills are required to recognise symptoms and clinical manifestations. This review focuses on the most common neurologic complications to improve physician’s familiarity in determining the aetiology of these symptoms.

  19. Neurologic complications of vaccinations.

    Science.gov (United States)

    Miravalle, Augusto A; Schreiner, Teri

    2014-01-01

    This chapter reviews the most common neurologic disorders associated with common vaccines, evaluates the data linking the disorder with the vaccine, and discusses the potential mechanism of disease. A literature search was conducted in PubMed using a combination of the following terms: vaccines, vaccination, immunization, and neurologic complications. Data were also gathered from publications of the American Academy of Pediatrics Committee on Infectious Diseases, the World Health Organization, the US Centers for Disease Control and Prevention, and the Vaccine Adverse Event Reporting System. Neurologic complications of vaccination are rare. Many associations have been asserted without objective data to support a causal relationship. Rarely, patients with a neurologic complication will have a poor outcome. However, most patients recover fully from the neurologic complication. Vaccinations have altered the landscape of infectious disease. However, perception of risk associated with vaccinations has limited the success of disease eradication measures. Neurologic complications can be severe, and can provoke fear in potential vaccines. Evaluating whether there is causal link between neurologic disorders and vaccinations, not just temporal association, is critical to addressing public misperception of risk of vaccination. Among the vaccines available today, the cost-benefit analysis of vaccinations and complications strongly argues in favor of vaccination. © 2014 Elsevier B.V. All rights reserved.

  20. Complications in Hip Arthroscopy

    Science.gov (United States)

    Nakano, Naoki; Khanduja, Vikas

    2016-01-01

    Summary Background Recent developments in hip arthroscopic techniques and technology have made it possible in many cases to avoid open surgical dislocation for treating a variety of pathology in the hip. Although early reports suggest favourable results’ using hip arthroscopy and it has been shown to be a relatively safe procedure, complications do exist and can sometimes lead to significant morbidity. Methods This is a review article. The aim of this manuscript is to present the most frequent and/or serious complications that could occur at or following hip arthroscopy and some guidelines to avoid these complications. Conclusion Most complications of hip arthroscopy are minor or transient but serious complications can occur as well. A lot of complication e.g. acetabular labral puncture go unreported. Appropriate education and training, precise and meticulous surgical technique with correct instrumentation, the right indication in the right patient and adherence to advice from mentors and experienced colleagues are all essential factors for a successful outcome. Level of evidence: V. PMID:28066747

  1. On complicity theory.

    Science.gov (United States)

    Kline, A David

    2006-04-01

    The received account of whistleblowing, developed over the last quarter century, is identified with the work of Norman Bowie and Richard DeGeorge. Michael Davis has detailed three anomalies for the received view: the paradoxes of burden, missing harm and failure. In addition, he has proposed an alternative account of whistleblowing, viz., the Complicity Theory. This paper examines the Complicity Theory. The supposed anomalies rest on misunderstandings of the received view or misreadings of model cases of whistleblowing, for example, the Challenger disaster and the Ford Pinto. Nevertheless, the Complicity Theory is important for as in science the contrast with alternative competing accounts often helps us better understand the received view. Several aspects of the received view are reviewed and strengthened through comparison with Complicity Theory, including why whistleblowing needs moral justification. Complicity Theory is also critiqued. The fundamental failure of Complicity Theory is its failure to explain why government and the public encourage and protect whistleblowers despite the possibility of considerable harm to the relevant company in reputation, lost jobs, and lost shareholder value.

  2. Probability inequalities for decomposition integrals

    Czech Academy of Sciences Publication Activity Database

    Agahi, H.; Mesiar, Radko

    2017-01-01

    Roč. 315, č. 1 (2017), s. 240-248 ISSN 0377-0427 Institutional support: RVO:67985556 Keywords : Decomposition integral * Superdecomposition integral * Probability inequalities Subject RIV: BA - General Mathematics OBOR OECD: Statistics and probability Impact factor: 1.357, year: 2016 http://library.utia.cas.cz/separaty/2017/E/mesiar-0470959.pdf

  3. Expected utility with lower probabilities

    DEFF Research Database (Denmark)

    Hendon, Ebbe; Jacobsen, Hans Jørgen; Sloth, Birgitte

    1994-01-01

    An uncertain and not just risky situation may be modeled using so-called belief functions assigning lower probabilities to subsets of outcomes. In this article we extend the von Neumann-Morgenstern expected utility theory from probability measures to belief functions. We use this theory...

  4. Invariant probabilities of transition functions

    CERN Document Server

    Zaharopol, Radu

    2014-01-01

    The structure of the set of all the invariant probabilities and the structure of various types of individual invariant probabilities of a transition function are two topics of significant interest in the theory of transition functions, and are studied in this book. The results obtained are useful in ergodic theory and the theory of dynamical systems, which, in turn, can be applied in various other areas (like number theory). They are illustrated using transition functions defined by flows, semiflows, and one-parameter convolution semigroups of probability measures. In this book, all results on transition probabilities that have been published by the author between 2004 and 2008 are extended to transition functions. The proofs of the results obtained are new. For transition functions that satisfy very general conditions the book describes an ergodic decomposition that provides relevant information on the structure of the corresponding set of invariant probabilities. Ergodic decomposition means a splitting of t...

  5. Introduction to probability with Mathematica

    CERN Document Server

    Hastings, Kevin J

    2009-01-01

    Discrete ProbabilityThe Cast of Characters Properties of Probability Simulation Random SamplingConditional ProbabilityIndependenceDiscrete DistributionsDiscrete Random Variables, Distributions, and ExpectationsBernoulli and Binomial Random VariablesGeometric and Negative Binomial Random Variables Poisson DistributionJoint, Marginal, and Conditional Distributions More on ExpectationContinuous ProbabilityFrom the Finite to the (Very) Infinite Continuous Random Variables and DistributionsContinuous ExpectationContinuous DistributionsThe Normal Distribution Bivariate Normal DistributionNew Random Variables from OldOrder Statistics Gamma DistributionsChi-Square, Student's t, and F-DistributionsTransformations of Normal Random VariablesAsymptotic TheoryStrong and Weak Laws of Large Numbers Central Limit TheoremStochastic Processes and ApplicationsMarkov ChainsPoisson Processes QueuesBrownian MotionFinancial MathematicsAppendixIntroduction to Mathematica Glossary of Mathematica Commands for Probability Short Answers...

  6. Local stem cell depletion model for normal tissue damage

    International Nuclear Information System (INIS)

    Yaes, R.J.; Keland, A.

    1987-01-01

    The hypothesis that radiation causes normal tissue damage by completely depleting local regions of tissue of viable stem cells leads to a simple mathematical model for such damage. In organs like skin and spinal cord where destruction of a small volume of tissue leads to a clinically apparent complication, the complication probability is expressed as a function of dose, volume and stem cell number by a simple triple negative exponential function analogous to the double exponential function of Munro and Gilbert for tumor control. The steep dose response curves for radiation myelitis that are obtained with our model are compared with the experimental data for radiation myelitis in laboratory rats. The model can be generalized to include other types or organs, high LET radiation, fractionated courses of radiation, and cases where an organ with a heterogeneous stem cell population receives an inhomogeneous dose of radiation. In principle it would thus be possible to determine the probability of tumor control and of damage to any organ within the radiation field if the dose distribution in three dimensional space within a patient is known

  7. Linear positivity and virtual probability

    International Nuclear Information System (INIS)

    Hartle, James B.

    2004-01-01

    We investigate the quantum theory of closed systems based on the linear positivity decoherence condition of Goldstein and Page. The objective of any quantum theory of a closed system, most generally the universe, is the prediction of probabilities for the individual members of sets of alternative coarse-grained histories of the system. Quantum interference between members of a set of alternative histories is an obstacle to assigning probabilities that are consistent with the rules of probability theory. A quantum theory of closed systems therefore requires two elements: (1) a condition specifying which sets of histories may be assigned probabilities and (2) a rule for those probabilities. The linear positivity condition of Goldstein and Page is the weakest of the general conditions proposed so far. Its general properties relating to exact probability sum rules, time neutrality, and conservation laws are explored. Its inconsistency with the usual notion of independent subsystems in quantum mechanics is reviewed. Its relation to the stronger condition of medium decoherence necessary for classicality is discussed. The linear positivity of histories in a number of simple model systems is investigated with the aim of exhibiting linearly positive sets of histories that are not decoherent. The utility of extending the notion of probability to include values outside the range of 0-1 is described. Alternatives with such virtual probabilities cannot be measured or recorded, but can be used in the intermediate steps of calculations of real probabilities. Extended probabilities give a simple and general way of formulating quantum theory. The various decoherence conditions are compared in terms of their utility for characterizing classicality and the role they might play in further generalizations of quantum mechanics

  8. Measles and its Complications

    African Journals Online (AJOL)

    1974-05-15

    May 15, 1974 ... a combination of hilar adenopathy and blood-vessel congestion, and pleural ... carditis. is sometimes accompanied by an enlarged heart shadow on ... probably due to lymphadenopathy and surrounding lung infection.

  9. The probability and severity of decompression sickness

    Science.gov (United States)

    Hada, Ethan A.; Vann, Richard D.; Denoble, Petar J.

    2017-01-01

    Decompression sickness (DCS), which is caused by inert gas bubbles in tissues, is an injury of concern for scuba divers, compressed air workers, astronauts, and aviators. Case reports for 3322 air and N2-O2 dives, resulting in 190 DCS events, were retrospectively analyzed and the outcomes were scored as (1) serious neurological, (2) cardiopulmonary, (3) mild neurological, (4) pain, (5) lymphatic or skin, and (6) constitutional or nonspecific manifestations. Following standard U.S. Navy medical definitions, the data were grouped into mild—Type I (manifestations 4–6)–and serious–Type II (manifestations 1–3). Additionally, we considered an alternative grouping of mild–Type A (manifestations 3–6)–and serious–Type B (manifestations 1 and 2). The current U.S. Navy guidance allows for a 2% probability of mild DCS and a 0.1% probability of serious DCS. We developed a hierarchical trinomial (3-state) probabilistic DCS model that simultaneously predicts the probability of mild and serious DCS given a dive exposure. Both the Type I/II and Type A/B discriminations of mild and serious DCS resulted in a highly significant (p probability of ‘mild’ DCS resulted in a longer allowable bottom time for the same 2% limit. However, for the 0.1% serious DCS limit, we found a vastly decreased allowable bottom dive time for all dive depths. If the Type A/B scoring was assigned to outcome severity, the no decompression limits (NDL) for air dives were still controlled by the acceptable serious DCS risk limit rather than the acceptable mild DCS risk limit. However, in this case, longer NDL limits were allowed than with the Type I/II scoring. The trinomial model mild and serious probabilities agree reasonably well with the current air NDL only with the Type A/B scoring and when 0.2% risk of serious DCS is allowed. PMID:28296928

  10. Probability Machines: Consistent Probability Estimation Using Nonparametric Learning Machines

    Science.gov (United States)

    Malley, J. D.; Kruppa, J.; Dasgupta, A.; Malley, K. G.; Ziegler, A.

    2011-01-01

    Summary Background Most machine learning approaches only provide a classification for binary responses. However, probabilities are required for risk estimation using individual patient characteristics. It has been shown recently that every statistical learning machine known to be consistent for a nonparametric regression problem is a probability machine that is provably consistent for this estimation problem. Objectives The aim of this paper is to show how random forests and nearest neighbors can be used for consistent estimation of individual probabilities. Methods Two random forest algorithms and two nearest neighbor algorithms are described in detail for estimation of individual probabilities. We discuss the consistency of random forests, nearest neighbors and other learning machines in detail. We conduct a simulation study to illustrate the validity of the methods. We exemplify the algorithms by analyzing two well-known data sets on the diagnosis of appendicitis and the diagnosis of diabetes in Pima Indians. Results Simulations demonstrate the validity of the method. With the real data application, we show the accuracy and practicality of this approach. We provide sample code from R packages in which the probability estimation is already available. This means that all calculations can be performed using existing software. Conclusions Random forest algorithms as well as nearest neighbor approaches are valid machine learning methods for estimating individual probabilities for binary responses. Freely available implementations are available in R and may be used for applications. PMID:21915433

  11. Probable Inference and Quantum Mechanics

    International Nuclear Information System (INIS)

    Grandy, W. T. Jr.

    2009-01-01

    In its current very successful interpretation the quantum theory is fundamentally statistical in nature. Although commonly viewed as a probability amplitude whose (complex) square is a probability, the wavefunction or state vector continues to defy consensus as to its exact meaning, primarily because it is not a physical observable. Rather than approach this problem directly, it is suggested that it is first necessary to clarify the precise role of probability theory in quantum mechanics, either as applied to, or as an intrinsic part of the quantum theory. When all is said and done the unsurprising conclusion is that quantum mechanics does not constitute a logic and probability unto itself, but adheres to the long-established rules of classical probability theory while providing a means within itself for calculating the relevant probabilities. In addition, the wavefunction is seen to be a description of the quantum state assigned by an observer based on definite information, such that the same state must be assigned by any other observer based on the same information, in much the same way that probabilities are assigned.

  12. Thrombophilia in complicated pregnancies

    Directory of Open Access Journals (Sweden)

    Ayşe Şahin

    2013-12-01

    Full Text Available Objective: To investigate the incidence and etiology of pregnancy complications associated with thrombophilic factors. Methods: Fifty-four patients with complicated pregnancy and 40 healthy pregnant subjects were included the study. Factor V Leiden (FVL mutation, protein S, protein C, anti-thrombin deficiency levels were investigated. Results: Of the 54 patients with complicated pregnancy, 29 had preeclampsia, 18 had intra uterine growth retardation, and 7 had intrauterine fetal loss. The most common defect was FVL mutation. FVL mutations in patient group and the control group were 27.2% and 10%, respectively, which were statistically significant. The protein S, protein C, and anti-thrombin deficiencies were found higher in the patient group compared to control (p>0.05 for each. Conclusion: FVL mutation was found higher in patient group compared to the control group, Protein C deficiency and anti-thrombin deficiency were related to preeclampsia but not other pregnancy complications. Clinicians should take into account the thrombophilia in complicated pregnancy, especially preeclampsia. J Clin Exp Invest 2013; 4 (4: 497-502

  13. Failure probability under parameter uncertainty.

    Science.gov (United States)

    Gerrard, R; Tsanakas, A

    2011-05-01

    In many problems of risk analysis, failure is equivalent to the event of a random risk factor exceeding a given threshold. Failure probabilities can be controlled if a decisionmaker is able to set the threshold at an appropriate level. This abstract situation applies, for example, to environmental risks with infrastructure controls; to supply chain risks with inventory controls; and to insurance solvency risks with capital controls. However, uncertainty around the distribution of the risk factor implies that parameter error will be present and the measures taken to control failure probabilities may not be effective. We show that parameter uncertainty increases the probability (understood as expected frequency) of failures. For a large class of loss distributions, arising from increasing transformations of location-scale families (including the log-normal, Weibull, and Pareto distributions), the article shows that failure probabilities can be exactly calculated, as they are independent of the true (but unknown) parameters. Hence it is possible to obtain an explicit measure of the effect of parameter uncertainty on failure probability. Failure probability can be controlled in two different ways: (1) by reducing the nominal required failure probability, depending on the size of the available data set, and (2) by modifying of the distribution itself that is used to calculate the risk control. Approach (1) corresponds to a frequentist/regulatory view of probability, while approach (2) is consistent with a Bayesian/personalistic view. We furthermore show that the two approaches are consistent in achieving the required failure probability. Finally, we briefly discuss the effects of data pooling and its systemic risk implications. © 2010 Society for Risk Analysis.

  14. PATTERNS OF SEVEN AND COMPLICATED MALARIA IN CHILDREN

    African Journals Online (AJOL)

    GB

    challenging disease for physicians due to the variability in its ... venous blood and erythema due to reactive hyperemia ... severe and may lead to digital ulcers, tissue necrosis and ... resultant complications relating to gangrene or systemic ...

  15. Probability with applications and R

    CERN Document Server

    Dobrow, Robert P

    2013-01-01

    An introduction to probability at the undergraduate level Chance and randomness are encountered on a daily basis. Authored by a highly qualified professor in the field, Probability: With Applications and R delves into the theories and applications essential to obtaining a thorough understanding of probability. With real-life examples and thoughtful exercises from fields as diverse as biology, computer science, cryptology, ecology, public health, and sports, the book is accessible for a variety of readers. The book's emphasis on simulation through the use of the popular R software language c

  16. A philosophical essay on probabilities

    CERN Document Server

    Laplace, Marquis de

    1996-01-01

    A classic of science, this famous essay by ""the Newton of France"" introduces lay readers to the concepts and uses of probability theory. It is of especial interest today as an application of mathematical techniques to problems in social and biological sciences.Generally recognized as the founder of the modern phase of probability theory, Laplace here applies the principles and general results of his theory ""to the most important questions of life, which are, in effect, for the most part, problems in probability."" Thus, without the use of higher mathematics, he demonstrates the application

  17. Oral complications of radiation therapy

    International Nuclear Information System (INIS)

    Lockhart, P.B.

    1986-01-01

    Approximately 24,000 patients are diagnosed each year with malignant tumors of the head and neck. Many of these patients will be treated with radiotherapy, surgery, or chemotherapy, either singly or in combination. Certain predictable sequelae of radiotherapy exist that may be considered consequences of treatment rather than complications; these may be unavoidable consequences of curative radiotherapy to the head and neck. There are, however, additional problems that occur as a result of radiotherapy that are preventable in both incidence and severity, and are therefore avoidable complications. Cell kinetic factors, radiosensitivity of normal tissues, radiotherapeutic doses necessary for tumor control, and the complex anatomy of the maxillofacial region often predispose patients serious treatment morbidity. The potential for pain, infection, and long-term functional disability with decreased quality of life dictate conscientious management before, during, and after radiotherapy. This chapter discusses common problems that can arise, as well as current methods utilized both to improve patient tolerance to treatment and to decrease the risk of preventable and potentially dose-limiting morbidity

  18. Post dengue neurological complication

    Directory of Open Access Journals (Sweden)

    Hizlinda Tohid

    2015-12-01

    Full Text Available Dengue infection is highly endemic in many tropical countries including Malaysia. However, neurological complications arising from dengue infection is not common; Gullain–Barre syndrome (GBS is one of these infrequent complications. In this paper, we have reported a case in which a 39-year-old woman presented with a neurological complication of dengue infection without typical symptoms and signs of dengue fever. She had a history of acute gastroenteritis (AGE followed by an upper respiratory tract infection (URTI weeks prior to her presentation rendering GBS secondary to the post viral URTI and AGE as the most likely diagnosis. Presence of thrombocytopenia was the only clue for dengue in this case.

  19. Imaging of postpartum complications

    International Nuclear Information System (INIS)

    Rooholamini, S.A.; Au, A.H.; Hansen, G.C.; Kioumehr, F.; Yaghmai, I.

    1991-01-01

    The purpose of this paper is to evaluate the efficacy of various imaging modalities in the detection of postpartum complications. Nineteen cases of postpartum complications, studied radiologically, form the basis of this exhibit. Plain abdominal radiography, US, CT, and MR imaging were performed alone or in combination. The abnormalities detected included uterine rupture, intramural uterine hematoma, hematomas of the broad ligaments and the abdominal rectus muscles, ovarian vein thrombosis, HELLP syndrome, pyometrium, retained placenta and blood clots, periappendiceal abscess, superior sagittal sinus thrombosis, and cerebral edema. Representative cases will be illustrated; and the effective value of each technique will be stressed

  20. Complications of cosmetic tattoos.

    Science.gov (United States)

    De Cuyper, Christa

    2015-01-01

    Cosmetic tattoos, which are better known as permanent make-up, have become popular in the last decades. This same procedure can be used to camouflage pathological skin conditions, to mask scars and to complete the aesthetic results of plastic and reconstructive surgeries. The risks and complications of tattooing procedures include infections and allergic reactions. Scarring can occur. Fanning and fading of the colorants and dissatisfaction with colour and shape are not unusual. Different lasers can offer solutions for the removal of unwanted cosmetic tattoos, but complications due to the laser treatment, such as paradoxical darkening and scarring, can arise. © 2015 S. Karger AG, Basel.

  1. Logic, probability, and human reasoning.

    Science.gov (United States)

    Johnson-Laird, P N; Khemlani, Sangeet S; Goodwin, Geoffrey P

    2015-04-01

    This review addresses the long-standing puzzle of how logic and probability fit together in human reasoning. Many cognitive scientists argue that conventional logic cannot underlie deductions, because it never requires valid conclusions to be withdrawn - not even if they are false; it treats conditional assertions implausibly; and it yields many vapid, although valid, conclusions. A new paradigm of probability logic allows conclusions to be withdrawn and treats conditionals more plausibly, although it does not address the problem of vapidity. The theory of mental models solves all of these problems. It explains how people reason about probabilities and postulates that the machinery for reasoning is itself probabilistic. Recent investigations accordingly suggest a way to integrate probability and deduction. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Free probability and random matrices

    CERN Document Server

    Mingo, James A

    2017-01-01

    This volume opens the world of free probability to a wide variety of readers. From its roots in the theory of operator algebras, free probability has intertwined with non-crossing partitions, random matrices, applications in wireless communications, representation theory of large groups, quantum groups, the invariant subspace problem, large deviations, subfactors, and beyond. This book puts a special emphasis on the relation of free probability to random matrices, but also touches upon the operator algebraic, combinatorial, and analytic aspects of the theory. The book serves as a combination textbook/research monograph, with self-contained chapters, exercises scattered throughout the text, and coverage of important ongoing progress of the theory. It will appeal to graduate students and all mathematicians interested in random matrices and free probability from the point of view of operator algebras, combinatorics, analytic functions, or applications in engineering and statistical physics.

  3. Introduction to probability and measure

    CERN Document Server

    Parthasarathy, K R

    2005-01-01

    According to a remark attributed to Mark Kac 'Probability Theory is a measure theory with a soul'. This book with its choice of proofs, remarks, examples and exercises has been prepared taking both these aesthetic and practical aspects into account.

  4. Joint probabilities and quantum cognition

    International Nuclear Information System (INIS)

    Acacio de Barros, J.

    2012-01-01

    In this paper we discuss the existence of joint probability distributions for quantumlike response computations in the brain. We do so by focusing on a contextual neural-oscillator model shown to reproduce the main features of behavioral stimulus-response theory. We then exhibit a simple example of contextual random variables not having a joint probability distribution, and describe how such variables can be obtained from neural oscillators, but not from a quantum observable algebra.

  5. Joint probabilities and quantum cognition

    Energy Technology Data Exchange (ETDEWEB)

    Acacio de Barros, J. [Liberal Studies, 1600 Holloway Ave., San Francisco State University, San Francisco, CA 94132 (United States)

    2012-12-18

    In this paper we discuss the existence of joint probability distributions for quantumlike response computations in the brain. We do so by focusing on a contextual neural-oscillator model shown to reproduce the main features of behavioral stimulus-response theory. We then exhibit a simple example of contextual random variables not having a joint probability distribution, and describe how such variables can be obtained from neural oscillators, but not from a quantum observable algebra.

  6. Default probabilities and default correlations

    OpenAIRE

    Erlenmaier, Ulrich; Gersbach, Hans

    2001-01-01

    Starting from the Merton framework for firm defaults, we provide the analytics and robustness of the relationship between default correlations. We show that loans with higher default probabilities will not only have higher variances but also higher correlations between loans. As a consequence, portfolio standard deviation can increase substantially when loan default probabilities rise. This result has two important implications. First, relative prices of loans with different default probabili...

  7. The Probabilities of Unique Events

    Science.gov (United States)

    2012-08-30

    Washington, DC USA Max Lotstein and Phil Johnson-Laird Department of Psychology Princeton University Princeton, NJ USA August 30th 2012...social justice and also participated in antinuclear demonstrations. The participants ranked the probability that Linda is a feminist bank teller as...retorted that such a flagrant violation of the probability calculus was a result of a psychological experiment that obscured the rationality of the

  8. Probability Matching, Fast and Slow

    OpenAIRE

    Koehler, Derek J.; James, Greta

    2014-01-01

    A prominent point of contention among researchers regarding the interpretation of probability-matching behavior is whether it represents a cognitively sophisticated, adaptive response to the inherent uncertainty of the tasks or settings in which it is observed, or whether instead it represents a fundamental shortcoming in the heuristics that support and guide human decision making. Put crudely, researchers disagree on whether probability matching is "smart" or "dumb." Here, we consider eviden...

  9. Complications 15 years after breast augmentation with polyacrylamide

    Directory of Open Access Journals (Sweden)

    Habib M. Ghasemi

    2015-06-01

    Full Text Available Polyacrylamide hydrogel (PAAG has been used as an injectable, permanent filler for soft-tissue augmentation for more than two decades. Several complications have been reported worldwide. In this case report, we present a woman with long-term complications 15 years after bilateral breast augmentation with PAAG injections.

  10. Complications 15 years after breast augmentation with polyacrylamide

    DEFF Research Database (Denmark)

    Ghasemi, Habib; Damsgaard, Tine Engberg; Stolle, Lars Bjørn

    2015-01-01

    Polyacrylamide hydrogel (PAAG) has been used as an injectable, permanent filler for soft-tissue augmentation for more than two decades. Several complications have been reported worldwide. In this case report, we present a woman with long-term complications 15 years after bilateral breast augmenta...

  11. Complication with intraosseous access

    DEFF Research Database (Denmark)

    Hallas, Peter; Brabrand, Mikkel; Folkestad, Lars

    2013-01-01

    with aspiration of bone marrow (12.3%), and bended/broken needle (4.0%). When using an established IO access the reported complications were difficulties with injection fluid and drugs after IO insertion (7.4%), slow infusion (despite use of pressure bag) (8.8%), displacement after insertion (8...

  12. Anticoagulation in pregnancy complications

    NARCIS (Netherlands)

    Middeldorp, Saskia

    2014-01-01

    Women with acquired and inherited thrombophilia are thought to be at increased risk for pregnancy complications, including recurrent pregnancy loss and, depending on the type of thrombophilia, severe preeclampsia. This review discusses the associations between the types of thrombophilia and types of

  13. Cardiovascular Complications of Pregnancy

    Science.gov (United States)

    Gongora, Maria Carolina; Wenger, Nanette K.

    2015-01-01

    Pregnancy causes significant metabolic and hemodynamic changes in a woman’s physiology to allow for fetal growth. The inability to adapt to these changes might result in the development of hypertensive disorders of pregnancy (hypertension, preeclampsia or eclampsia), gestational diabetes and preterm birth. Contrary to previous beliefs these complications are not limited to the pregnancy period and may leave permanent vascular and metabolic damage. There is in addition, a direct association between these disorders and increased risk of future cardiovascular disease (CVD, including hypertension, ischemic heart disease, heart failure and stroke) and diabetes mellitus. Despite abundant evidence of this association, women who present with these complications of pregnancy do not receive adequate postpartum follow up and counseling regarding their increased risk of future CVD. The postpartum period in these women represents a unique opportunity to intervene with lifestyle modifications designed to reduce the development of premature cardiovascular complications. In some cases it allows early diagnosis and treatment of chronic hypertension or diabetes mellitus. The awareness of this relationship is growing in the medical community, especially among obstetricians and primary care physicians, who play a pivotal role in detecting these complications and assuring appropriate follow up. PMID:26473833

  14. Atrial Fibrillation: Complications

    Science.gov (United States)

    ... of this page please turn JavaScript on. Feature: Atrial Fibrillation Atrial Fibrillation: Complications Past Issues / Winter 2015 Table of Contents ... has two major complications—stroke and heart failure. Atrial Fibrillation and Stroke Click to enlarge image This illustration ...

  15. Complicating Methodological Transparency

    Science.gov (United States)

    Bridges-Rhoads, Sarah; Van Cleave, Jessica; Hughes, Hilary E.

    2016-01-01

    A historical indicator of the quality, validity, and rigor of qualitative research has been the documentation and disclosure of the behind-the-scenes work of the researcher. In this paper, we use what we call "methodological data" as a tool to complicate the possibility and desirability of such transparency. Specifically, we draw on our…

  16. Cardiovascular Complications of Pregnancy

    Directory of Open Access Journals (Sweden)

    Maria Carolina Gongora

    2015-10-01

    Full Text Available Pregnancy causes significant metabolic and hemodynamic changes in a woman’s physiology to allow for fetal growth. The inability to adapt to these changes might result in the development of hypertensive disorders of pregnancy (hypertension, preeclampsia or eclampsia, gestational diabetes and preterm birth. Contrary to previous beliefs these complications are not limited to the pregnancy period and may leave permanent vascular and metabolic damage. There is in addition, a direct association between these disorders and increased risk of future cardiovascular disease (CVD, including hypertension, ischemic heart disease, heart failure and stroke and diabetes mellitus. Despite abundant evidence of this association, women who present with these complications of pregnancy do not receive adequate postpartum follow up and counseling regarding their increased risk of future CVD. The postpartum period in these women represents a unique opportunity to intervene with lifestyle modifications designed to reduce the development of premature cardiovascular complications. In some cases it allows early diagnosis and treatment of chronic hypertension or diabetes mellitus. The awareness of this relationship is growing in the medical community, especially among obstetricians and primary care physicians, who play a pivotal role in detecting these complications and assuring appropriate follow up.

  17. Medical complications following splenectomy.

    Science.gov (United States)

    Buzelé, R; Barbier, L; Sauvanet, A; Fantin, B

    2016-08-01

    Splenectomy is attended by medical complications, principally infectious and thromboembolic; the frequency of complications varies with the conditions that led to splenectomy (hematologic splenectomy, trauma, presence of portal hypertension). Most infectious complications are caused by encapsulated bacteria (Meningococcus, Pneumococcus, Hemophilus). These occur mainly in children and somewhat less commonly in adults within the first two years following splenectomy. Post-splenectomy infections are potentially severe with overwhelming post-splenectomy infection (OPSI) and this justifies preventive measures (prophylactic antibiotics, appropriate immunizations, patient education) and demands prompt antibiotic management with third-generation cephalosporins for any post-splenectomy fever. Thromboembolic complications can involve both the caval system (deep-vein thrombophlebitis, pulmonary embolism) and the portal system. Portal vein thrombosis occurs more commonly in patients with myeloproliferative disease and cirrhosis. No thromboembolic prophylaxis is recommended apart from perioperative low molecular weight heparin. However, some authors choose to prescribe a short course of anti-platelet medication if the post-splenectomy patient develops significant thrombocytosis. Thrombosis of the portal or caval venous system requires prolonged warfarin anticoagulation for 3 to 6 months. Finally, some studies have suggested an increase in the long-term incidence of cancer in splenectomized patients. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  18. Pregnancy Complications: Placental Abruption

    Science.gov (United States)

    ... at risk? Zika virus and pregnancy Folic acid Medicine safety and pregnancy Birth defects prevention Learn how to help reduce ... high blood pressure, not smoking or using street drugs, and always wearing a seatbelt when riding in a car. ... complications Preterm labor & premature birth The newborn intensive ...

  19. Treatment of complicated grief

    Directory of Open Access Journals (Sweden)

    Rita Rosner

    2011-11-01

    Full Text Available Following the death of a loved one, a small group of grievers develop an abnormal grieving style, termed complicated or prolonged grief. In the effort to establish complicated grief as a disorder in DSM and ICD, several attempts have been made over the past two decades to establish symptom criteria for this form of grieving. Complicated grief is different from depression and PTSD yet often comorbid with other psychological disorders. Meta-analyses of grief interventions show small to medium effect sizes, with only few studies yielding large effect sizes. In this article, an integrative cognitive behavioral treatment manual for complicated grief disorder (CG-CBT of 25 individual sessions is described. Three treatment phases, each entailing several treatment strategies, allow patients to stabilize, explore, and confront the most painful aspects of the loss, and finally to integrate and transform their grief. Core aspects are cognitive restructuring and confrontation. Special attention is given to practical exercises. This article includes the case report of a woman whose daughter committed suicide.

  20. Optimization of the dose level for a given treatment plan to maximize the complication-free tumor cure

    International Nuclear Information System (INIS)

    Lind, B.K.; Mavroidis, P.; Hyoedynmaa, S.; Kappas, C.

    1999-01-01

    During the past decade, tumor and normal tissue reactions after radiotherapy have been increasingly quantified in radiobiological terms. For this purpose, response models describing the dependence of tumor and normal tissue reactions on the irradiated volume, heterogeneity of the delivered dose distribution and cell sensitivity variations can be taken into account. The probability of achieving a good treatment outcome can be increased by using an objective function such as P + , the probability of complication-free tumor control. A new procedure is presented, which quantifies P + from the dose delivery on 2D surfaces and 3D volumes and helps the user of any treatment planning system (TPS) to select the best beam orientations, the best beam modalities and the most suitable beam energies. The final step of selecting the prescribed dose level is made by a renormalization of the entire dose plan until the value of P + is maximized. The index P + makes use of clinically established dose-response parameters, for tumors and normal tissues of interest, in order to improve its clinical relevance. The results, using P + , are compared against the assessments of experienced medical physicists and radiation oncologists for two clinical cases. It is observed that when the absorbed dose level for a given treatment plan is increased, the treatment outcome first improves rapidly. As the dose approaches the tolerance of normal tissues the complication-free curve begins to drop. The optimal dose level is often just below this point and it depends on the geometry of each patient and target volume. Furthermore, a more conformal dose delivery to the target results in a higher control rate for the same complication level. This effect can be quantified by the increased value of the P + parameter. (orig.)

  1. Probably not future prediction using probability and statistical inference

    CERN Document Server

    Dworsky, Lawrence N

    2008-01-01

    An engaging, entertaining, and informative introduction to probability and prediction in our everyday lives Although Probably Not deals with probability and statistics, it is not heavily mathematical and is not filled with complex derivations, proofs, and theoretical problem sets. This book unveils the world of statistics through questions such as what is known based upon the information at hand and what can be expected to happen. While learning essential concepts including "the confidence factor" and "random walks," readers will be entertained and intrigued as they move from chapter to chapter. Moreover, the author provides a foundation of basic principles to guide decision making in almost all facets of life including playing games, developing winning business strategies, and managing personal finances. Much of the book is organized around easy-to-follow examples that address common, everyday issues such as: How travel time is affected by congestion, driving speed, and traffic lights Why different gambling ...

  2. Normal probability plots with confidence.

    Science.gov (United States)

    Chantarangsi, Wanpen; Liu, Wei; Bretz, Frank; Kiatsupaibul, Seksan; Hayter, Anthony J; Wan, Fang

    2015-01-01

    Normal probability plots are widely used as a statistical tool for assessing whether an observed simple random sample is drawn from a normally distributed population. The users, however, have to judge subjectively, if no objective rule is provided, whether the plotted points fall close to a straight line. In this paper, we focus on how a normal probability plot can be augmented by intervals for all the points so that, if the population distribution is normal, then all the points should fall into the corresponding intervals simultaneously with probability 1-α. These simultaneous 1-α probability intervals provide therefore an objective mean to judge whether the plotted points fall close to the straight line: the plotted points fall close to the straight line if and only if all the points fall into the corresponding intervals. The powers of several normal probability plot based (graphical) tests and the most popular nongraphical Anderson-Darling and Shapiro-Wilk tests are compared by simulation. Based on this comparison, recommendations are given in Section 3 on which graphical tests should be used in what circumstances. An example is provided to illustrate the methods. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Probability theory a foundational course

    CERN Document Server

    Pakshirajan, R P

    2013-01-01

    This book shares the dictum of J. L. Doob in treating Probability Theory as a branch of Measure Theory and establishes this relation early. Probability measures in product spaces are introduced right at the start by way of laying the ground work to later claim the existence of stochastic processes with prescribed finite dimensional distributions. Other topics analysed in the book include supports of probability measures, zero-one laws in product measure spaces, Erdos-Kac invariance principle, functional central limit theorem and functional law of the iterated logarithm for independent variables, Skorohod embedding, and the use of analytic functions of a complex variable in the study of geometric ergodicity in Markov chains. This book is offered as a text book for students pursuing graduate programs in Mathematics and or Statistics. The book aims to help the teacher present the theory with ease, and to help the student sustain his interest and joy in learning the subject.

  4. VIBRATION ISOLATION SYSTEM PROBABILITY ANALYSIS

    Directory of Open Access Journals (Sweden)

    Smirnov Vladimir Alexandrovich

    2012-10-01

    Full Text Available The article deals with the probability analysis for a vibration isolation system of high-precision equipment, which is extremely sensitive to low-frequency oscillations even of submicron amplitude. The external sources of low-frequency vibrations may include the natural city background or internal low-frequency sources inside buildings (pedestrian activity, HVAC. Taking Gauss distribution into account, the author estimates the probability of the relative displacement of the isolated mass being still lower than the vibration criteria. This problem is being solved in the three dimensional space, evolved by the system parameters, including damping and natural frequency. According to this probability distribution, the chance of exceeding the vibration criteria for a vibration isolation system is evaluated. Optimal system parameters - damping and natural frequency - are being developed, thus the possibility of exceeding vibration criteria VC-E and VC-D is assumed to be less than 0.04.

  5. Approximation methods in probability theory

    CERN Document Server

    Čekanavičius, Vydas

    2016-01-01

    This book presents a wide range of well-known and less common methods used for estimating the accuracy of probabilistic approximations, including the Esseen type inversion formulas, the Stein method as well as the methods of convolutions and triangle function. Emphasising the correct usage of the methods presented, each step required for the proofs is examined in detail. As a result, this textbook provides valuable tools for proving approximation theorems. While Approximation Methods in Probability Theory will appeal to everyone interested in limit theorems of probability theory, the book is particularly aimed at graduate students who have completed a standard intermediate course in probability theory. Furthermore, experienced researchers wanting to enlarge their toolkit will also find this book useful.

  6. Nocardia brasiliensis Infection Complicating Cryptogenic Organizing Pneumonia.

    Science.gov (United States)

    Fernandes, Alison M; Sluzevich, Jason C; Mira-Avendano, Isabel

    2017-01-01

    Pulmonary nocardiosis is a severe and uncommon opportunistic infection caused by Nocardia species. We present a patient with cryptogenic organizing pneumonia who was receiving long-term immunosuppressive therapy, whose treatment course was complicated by cutaneous and pulmonary nocardiosis. Tissue cultures confirmed Nocardia brasiliensis . Nocardiosis should be a diagnostic consideration for patients treated with long-term immunosuppression who have worsening pulmonary symptoms and relapsing pustular skin lesions.

  7. Nocardia brasiliensis Infection Complicating Cryptogenic Organizing Pneumonia

    OpenAIRE

    Fernandes, Alison M.; Sluzevich, Jason C.; Mira-Avendano, Isabel

    2017-01-01

    Pulmonary nocardiosis is a severe and uncommon opportunistic infection caused by Nocardia species. We present a patient with cryptogenic organizing pneumonia who was receiving long-term immunosuppressive therapy, whose treatment course was complicated by cutaneous and pulmonary nocardiosis. Tissue cultures confirmed Nocardia brasiliensis. Nocardiosis should be a diagnostic consideration for patients treated with long-term immunosuppression who have worsening pulmonary symptoms and relapsing p...

  8. Nocardia brasiliensis Infection Complicating Cryptogenic Organizing Pneumonia

    Directory of Open Access Journals (Sweden)

    Alison M. Fernandes

    2017-01-01

    Full Text Available Pulmonary nocardiosis is a severe and uncommon opportunistic infection caused by Nocardia species. We present a patient with cryptogenic organizing pneumonia who was receiving long-term immunosuppressive therapy, whose treatment course was complicated by cutaneous and pulmonary nocardiosis. Tissue cultures confirmed Nocardia brasiliensis. Nocardiosis should be a diagnostic consideration for patients treated with long-term immunosuppression who have worsening pulmonary symptoms and relapsing pustular skin lesions.

  9. Neurological complications of alcoholism

    Directory of Open Access Journals (Sweden)

    I. I. Nikiforov

    2017-01-01

    Full Text Available Nervous system lesions associated with chronic alcohol intoxication are common in clinical practice. They lead to aggravated alcoholic disease, its more frequent recurrences, and intensified pathological craving for alcohol. Neurological pathology in turn occurs with frequent exacerbations. The interaction of diseases, age, and medical  pathomorphism modifies the clinical presentation and course of the  major pathology, as well as comorbidity, the nature and severity of  complications, worsens quality of life in a patient, and makes the  diagnostic and treatment process difficult. The paper discusses the  classification, clinical variants, biochemical and molecular biological  aspects of various complications of alcoholic disease. It considers its  most common form, in particular alcoholic polyneuropathy, as well as its rarer variants, such as hemorrhagic encephalopathy with a subacute course (Gayet–Wernicke encephalopathy.

  10. Gastrointestinal Complications of Obesity

    Science.gov (United States)

    Camilleri, Michael; Malhi, Harmeet; Acosta, Andres

    2017-01-01

    Obesity usually is associated with morbidity related to diabetes mellitus and cardiovascular diseases. However, there are many gastrointestinal and hepatic diseases for which obesity is the direct cause (eg, nonalcoholic fatty liver disease) or is a significant risk factor, such as reflux esophagitis and gallstones. When obesity is a risk factor, it may interact with other mechanisms and result in earlier presentation or complicated diseases. There are increased odds ratios or relative risks of several gastrointestinal complications of obesity: gastroesophageal reflux disease, erosive esophagitis, Barrett’s esophagus, esophageal adenocarcinoma, erosive gastritis, gastric cancer, diarrhea, colonic diverticular disease, polyps, cancer, liver disease including nonalcoholic fatty liver disease, cirrhosis, hepatocellular carcinoma, gallstones, acute pancreatitis, and pancreatic cancer. Gastroenterologists are uniquely poised to participate in the multidisciplinary management of obesity as physicians caring for people with obesity-related diseases, in addition to their expertise in nutrition and endoscopic interventions. PMID:28192107

  11. Model uncertainty: Probabilities for models?

    International Nuclear Information System (INIS)

    Winkler, R.L.

    1994-01-01

    Like any other type of uncertainty, model uncertainty should be treated in terms of probabilities. The question is how to do this. The most commonly-used approach has a drawback related to the interpretation of the probabilities assigned to the models. If we step back and look at the big picture, asking what the appropriate focus of the model uncertainty question should be in the context of risk and decision analysis, we see that a different probabilistic approach makes more sense, although it raise some implementation questions. Current work that is underway to address these questions looks very promising

  12. Knowledge typology for imprecise probabilities.

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, G. D. (Gregory D.); Zucker, L. J. (Lauren J.)

    2002-01-01

    When characterizing the reliability of a complex system there are often gaps in the data available for specific subsystems or other factors influencing total system reliability. At Los Alamos National Laboratory we employ ethnographic methods to elicit expert knowledge when traditional data is scarce. Typically, we elicit expert knowledge in probabilistic terms. This paper will explore how we might approach elicitation if methods other than probability (i.e., Dempster-Shafer, or fuzzy sets) prove more useful for quantifying certain types of expert knowledge. Specifically, we will consider if experts have different types of knowledge that may be better characterized in ways other than standard probability theory.

  13. Probability, Statistics, and Stochastic Processes

    CERN Document Server

    Olofsson, Peter

    2011-01-01

    A mathematical and intuitive approach to probability, statistics, and stochastic processes This textbook provides a unique, balanced approach to probability, statistics, and stochastic processes. Readers gain a solid foundation in all three fields that serves as a stepping stone to more advanced investigations into each area. This text combines a rigorous, calculus-based development of theory with a more intuitive approach that appeals to readers' sense of reason and logic, an approach developed through the author's many years of classroom experience. The text begins with three chapters that d

  14. Statistical probability tables CALENDF program

    International Nuclear Information System (INIS)

    Ribon, P.

    1989-01-01

    The purpose of the probability tables is: - to obtain dense data representation - to calculate integrals by quadratures. They are mainly used in the USA for calculations by Monte Carlo and in the USSR and Europe for self-shielding calculations by the sub-group method. The moment probability tables, in addition to providing a more substantial mathematical basis and calculation methods, are adapted for condensation and mixture calculations, which are the crucial operations for reactor physics specialists. However, their extension is limited by the statistical hypothesis they imply. Efforts are being made to remove this obstacle, at the cost, it must be said, of greater complexity

  15. Probability, statistics, and queueing theory

    CERN Document Server

    Allen, Arnold O

    1990-01-01

    This is a textbook on applied probability and statistics with computer science applications for students at the upper undergraduate level. It may also be used as a self study book for the practicing computer science professional. The successful first edition of this book proved extremely useful to students who need to use probability, statistics and queueing theory to solve problems in other fields, such as engineering, physics, operations research, and management science. The book has also been successfully used for courses in queueing theory for operations research students. This second edit

  16. Probability and Statistics: 5 Questions

    DEFF Research Database (Denmark)

    Probability and Statistics: 5 Questions is a collection of short interviews based on 5 questions presented to some of the most influential and prominent scholars in probability and statistics. We hear their views on the fields, aims, scopes, the future direction of research and how their work fits...... in these respects. Interviews with Nick Bingham, Luc Bovens, Terrence L. Fine, Haim Gaifman, Donald Gillies, James Hawthorne, Carl Hoefer, James M. Joyce, Joseph B. Kadane Isaac Levi, D.H. Mellor, Patrick Suppes, Jan von Plato, Carl Wagner, Sandy Zabell...

  17. Thrombophilia and Pregnancy Complications

    Directory of Open Access Journals (Sweden)

    Louise E. Simcox

    2015-11-01

    Full Text Available There is a paucity of strong evidence associated with adverse pregnancy outcomes and thrombophilia in pregnancy. These problems include both early (recurrent miscarriage and late placental vascular-mediated problems (fetal loss, pre-eclampsia, placental abruption and intra-uterine growth restriction. Due to poor quality case-control and cohort study designs, there is often an increase in the relative risk of these complications associated with thrombophilia, particularly recurrent early pregnancy loss, late fetal loss and pre-eclampsia, but the absolute risk remains very small. It appears that low-molecular weight heparin has other benefits on the placental vascular system besides its anticoagulant properties. Its use is in the context of antiphospholipid syndrome and recurrent pregnancy loss and also in women with implantation failure to improve live birth rates. There is currently no role for low-molecular weight heparin to prevent late placental-mediated complications in patients with inherited thrombophilia and this may be due to small patient numbers in the studies involved in summarising the evidence. There is potential for low-molecular weight heparin to improve pregnancy outcomes in women with prior severe vascular complications of pregnancy such as early-onset intra-uterine growth restriction and pre-eclampsia but further high quality randomised controlled trials are required to answer this question.

  18. Normal tissue dose-effect models in biological dose optimisation

    International Nuclear Information System (INIS)

    Alber, M.

    2008-01-01

    Sophisticated radiotherapy techniques like intensity modulated radiotherapy with photons and protons rely on numerical dose optimisation. The evaluation of normal tissue dose distributions that deviate significantly from the common clinical routine and also the mathematical expression of desirable properties of a dose distribution is difficult. In essence, a dose evaluation model for normal tissues has to express the tissue specific volume effect. A formalism of local dose effect measures is presented, which can be applied to serial and parallel responding tissues as well as target volumes and physical dose penalties. These models allow a transparent description of the volume effect and an efficient control over the optimum dose distribution. They can be linked to normal tissue complication probability models and the equivalent uniform dose concept. In clinical applications, they provide a means to standardize normal tissue doses in the face of inevitable anatomical differences between patients and a vastly increased freedom to shape the dose, without being overly limiting like sets of dose-volume constraints. (orig.)

  19. Elements of probability and statistics an introduction to probability with De Finetti’s approach and to Bayesian statistics

    CERN Document Server

    Biagini, Francesca

    2016-01-01

    This book provides an introduction to elementary probability and to Bayesian statistics using de Finetti's subjectivist approach. One of the features of this approach is that it does not require the introduction of sample space – a non-intrinsic concept that makes the treatment of elementary probability unnecessarily complicate – but introduces as fundamental the concept of random numbers directly related to their interpretation in applications. Events become a particular case of random numbers and probability a particular case of expectation when it is applied to events. The subjective evaluation of expectation and of conditional expectation is based on an economic choice of an acceptable bet or penalty. The properties of expectation and conditional expectation are derived by applying a coherence criterion that the evaluation has to follow. The book is suitable for all introductory courses in probability and statistics for students in Mathematics, Informatics, Engineering, and Physics.

  20. Quantification of late complications after radiation therapy

    International Nuclear Information System (INIS)

    Jung, Horst; Beck-Bornholdt, Hans-Peter; Svoboda, Vladimir; Alberti, Winfried; Herrmann, Thomas

    2001-01-01

    Background: An increasing number of patients survive cancer after having received radiation therapy. Therefore, the occurrence of late normal tissue complications among long-term survivors is of particular concern. Methods: Sixty-three patients treated by radical surgery and irradiation for rectal carcinoma were subjected to an unconventional sandwich therapy. Preoperative irradiation was given in four fractions of 5 Gy each applied within 2 or 3 days; postoperative irradiation consisted mostly of 15x2 Gy (range, 20-40 Gy). A considerable proportion of these patients developed severe late complications (Radiother Oncol 53 (1999) 177). The data allowed a detailed analysis of complication kinetics, leading to a new model which was tested using data from the literature. Results: Data on late complications were obtained for eight different organs with a follow-up of up to 10 years. For the various organs, the percentage of patients being free from late complications, plotted as a function of time after start of radiation therapy, was adequately described by exponential regression. From the fit, the parameter p a was obtained, which is the percentage of patients at risk in a given year of developing a complication in a given organ during that year. The rate p a remained about constant with time. Following sandwich therapy, the annual incidence of complications in the bladder, ileum, lymphatic and soft tissue, and ureters was about the same (p a =10-14%/year), whereas complications in bone or dermis occurred at lower rates (4.7 or 7.5%/year, respectively). Discussion: Numerous data sets collected from published reports were analyzed in the same way. Many of the data sets studied were from patients in a series where there was a high incidence of late effects. Three types of kinetics for the occurrence of late effects after radiotherapy were identified: Type 1, purely exponential kinetics; Type 2, exponential kinetics, the slope of which decreased exponentially with time

  1. Dynamic SEP event probability forecasts

    Science.gov (United States)

    Kahler, S. W.; Ling, A.

    2015-10-01

    The forecasting of solar energetic particle (SEP) event probabilities at Earth has been based primarily on the estimates of magnetic free energy in active regions and on the observations of peak fluxes and fluences of large (≥ M2) solar X-ray flares. These forecasts are typically issued for the next 24 h or with no definite expiration time, which can be deficient for time-critical operations when no SEP event appears following a large X-ray flare. It is therefore important to decrease the event probability forecast with time as a SEP event fails to appear. We use the NOAA listing of major (≥10 pfu) SEP events from 1976 to 2014 to plot the delay times from X-ray peaks to SEP threshold onsets as a function of solar source longitude. An algorithm is derived to decrease the SEP event probabilities with time when no event is observed to reach the 10 pfu threshold. In addition, we use known SEP event size distributions to modify probability forecasts when SEP intensity increases occur below the 10 pfu event threshold. An algorithm to provide a dynamic SEP event forecast, Pd, for both situations of SEP intensities following a large flare is derived.

  2. Conditional Independence in Applied Probability.

    Science.gov (United States)

    Pfeiffer, Paul E.

    This material assumes the user has the background provided by a good undergraduate course in applied probability. It is felt that introductory courses in calculus, linear algebra, and perhaps some differential equations should provide the requisite experience and proficiency with mathematical concepts, notation, and argument. The document is…

  3. Stretching Probability Explorations with Geoboards

    Science.gov (United States)

    Wheeler, Ann; Champion, Joe

    2016-01-01

    Students are faced with many transitions in their middle school mathematics classes. To build knowledge, skills, and confidence in the key areas of algebra and geometry, students often need to practice using numbers and polygons in a variety of contexts. Teachers also want students to explore ideas from probability and statistics. Teachers know…

  4. GPS: Geometry, Probability, and Statistics

    Science.gov (United States)

    Field, Mike

    2012-01-01

    It might be said that for most occupations there is now less of a need for mathematics than there was say fifty years ago. But, the author argues, geometry, probability, and statistics constitute essential knowledge for everyone. Maybe not the geometry of Euclid, but certainly geometrical ways of thinking that might enable us to describe the world…

  5. Swedish earthquakes and acceleration probabilities

    International Nuclear Information System (INIS)

    Slunga, R.

    1979-03-01

    A method to assign probabilities to ground accelerations for Swedish sites is described. As hardly any nearfield instrumental data is available we are left with the problem of interpreting macroseismic data in terms of acceleration. By theoretical wave propagation computations the relation between seismic strength of the earthquake, focal depth, distance and ground accelerations are calculated. We found that most Swedish earthquake of the area, the 1904 earthquake 100 km south of Oslo, is an exception and probably had a focal depth exceeding 25 km. For the nuclear power plant sites an annual probability of 10 -5 has been proposed as interesting. This probability gives ground accelerations in the range 5-20 % for the sites. This acceleration is for a free bedrock site. For consistency all acceleration results in this study are given for bedrock sites. When applicating our model to the 1904 earthquake and assuming the focal zone to be in the lower crust we get the epicentral acceleration of this earthquake to be 5-15 % g. The results above are based on an analyses of macrosismic data as relevant instrumental data is lacking. However, the macroseismic acceleration model deduced in this study gives epicentral ground acceleration of small Swedish earthquakes in agreement with existent distant instrumental data. (author)

  6. DECOFF Probabilities of Failed Operations

    DEFF Research Database (Denmark)

    Gintautas, Tomas

    2015-01-01

    A statistical procedure of estimation of Probabilities of Failed Operations is described and exemplified using ECMWF weather forecasts and SIMO output from Rotor Lift test case models. Also safety factor influence is investigated. DECOFF statistical method is benchmarked against standard Alpha-factor...

  7. Risk estimation using probability machines

    Science.gov (United States)

    2014-01-01

    Background Logistic regression has been the de facto, and often the only, model used in the description and analysis of relationships between a binary outcome and observed features. It is widely used to obtain the conditional probabilities of the outcome given predictors, as well as predictor effect size estimates using conditional odds ratios. Results We show how statistical learning machines for binary outcomes, provably consistent for the nonparametric regression problem, can be used to provide both consistent conditional probability estimation and conditional effect size estimates. Effect size estimates from learning machines leverage our understanding of counterfactual arguments central to the interpretation of such estimates. We show that, if the data generating model is logistic, we can recover accurate probability predictions and effect size estimates with nearly the same efficiency as a correct logistic model, both for main effects and interactions. We also propose a method using learning machines to scan for possible interaction effects quickly and efficiently. Simulations using random forest probability machines are presented. Conclusions The models we propose make no assumptions about the data structure, and capture the patterns in the data by just specifying the predictors involved and not any particular model structure. So they do not run the same risks of model mis-specification and the resultant estimation biases as a logistic model. This methodology, which we call a “risk machine”, will share properties from the statistical machine that it is derived from. PMID:24581306

  8. Probability and statistics: A reminder

    International Nuclear Information System (INIS)

    Clement, B.

    2013-01-01

    The main purpose of these lectures is to provide the reader with the tools needed to data analysis in the framework of physics experiments. Basic concepts are introduced together with examples of application in experimental physics. The lecture is divided into two parts: probability and statistics. It is build on the introduction from 'data analysis in experimental sciences' given in [1]. (authors)

  9. Nash equilibrium with lower probabilities

    DEFF Research Database (Denmark)

    Groes, Ebbe; Jacobsen, Hans Jørgen; Sloth, Birgitte

    1998-01-01

    We generalize the concept of Nash equilibrium in mixed strategies for strategic form games to allow for ambiguity in the players' expectations. In contrast to other contributions, we model ambiguity by means of so-called lower probability measures or belief functions, which makes it possible...

  10. On probability-possibility transformations

    Science.gov (United States)

    Klir, George J.; Parviz, Behzad

    1992-01-01

    Several probability-possibility transformations are compared in terms of the closeness of preserving second-order properties. The comparison is based on experimental results obtained by computer simulation. Two second-order properties are involved in this study: noninteraction of two distributions and projections of a joint distribution.

  11. Digital dice computational solutions to practical probability problems

    CERN Document Server

    Nahin, Paul J

    2013-01-01

    Some probability problems are so difficult that they stump the smartest mathematicians. But even the hardest of these problems can often be solved with a computer and a Monte Carlo simulation, in which a random-number generator simulates a physical process, such as a million rolls of a pair of dice. This is what Digital Dice is all about: how to get numerical answers to difficult probability problems without having to solve complicated mathematical equations. Popular-math writer Paul Nahin challenges readers to solve twenty-one difficult but fun problems, from determining the

  12. Hyperfractionation in carcinoma of the cervix: tumor control and late bowel complications

    International Nuclear Information System (INIS)

    Viswanathan, Faith Rangad; Varghese, Cherian; Peedicayil, Abraham; Lakshmanan, Jeyaseelan; Narayan, Viswanathan Perungulam

    1999-01-01

    Purpose: Hyperfractionation has been advocated to improve local tumor control by increasing radiation dose without increasing late normal tissue complications. The aim of this study was to determine if hyperfractionation decreased late bowel complications. Methods and Materials: Thirty patients with Stage II and III cervical cancer were randomized to receive either hyperfractionation or conventional fractionation. Patients were followed for 5 years and monitored for tumor control, recurrence, and bowel complications. The relative risks of tumor control and bowel complications were computed at 1 year and 5 years of follow-up. Kaplan-Meier survival curves were plotted to determine probabilities of being tumor-free and bowel complication-free. Results: There were 15 patients in each group. At 1 year of follow-up, 2 patients in the hyperfractionation group (13%) and 7 patients in the conventional treatment group (45%) had tumor (relative risk [RR] 0.3; 95% confidence interval [CI] 0.1, 1.1; p = 0.054). Delayed bowel complications were seen in 8 patients in the hyperfractionation group and 1 patient in the conventional treatment group (RR 7.5; 95% CI 1.1, 52; p = 0.014). At 5 years, 2 patients in the hyperfractionation group and 8 patients in the conventional treatment group had tumor (RR 0.3; 95% CI 0.1, 1.1; p = 0.04). Delayed bowel complications (Grades 2 and 3) occurred in 9 women in the hyperfractionation group and 2 patients in the conventional group (RR 5.4; 95% CI 1.5, 19.5; p 0.0006). Kaplan-Meier analysis showed that the hyperfractionation group had significantly more bowel complications over the 5 years of follow-up (p 0.024). Conclusion: Hyperfractionation may result in better tumor control both at 1 year and at 5 years following treatment of cervical cancer. However, hyperfractionation could lead to increased late bowel complications and must be used judiciously in the treatment of cervical cancer

  13. Simulation of intersection of complicated information signals in air traffic control systems

    Directory of Open Access Journals (Sweden)

    Е. В. Коба

    2000-12-01

    Full Text Available Considered is the problem of complicated system simulation with customers incoming flows. Developed is an algorithm accelerated of finding probability of the superposition of complicated customers. Derived are the top and bottom estimates of damage-factor which are connected with complical customers superposition. Noticed is connection with simulation problem of air traffic control system

  14. Neurological complications of Zika virus infection.

    Science.gov (United States)

    Carod-Artal, Francisco Javier

    2018-04-26

    Zika virus (ZIKV) disease is a vector-borne infectious disease transmitted by Aedes mosquitoes. Recently, ZIKV has caused outbreaks in most American countries. Areas covered: Publications about neurological complications of ZIKV infection retrieved from pubmed searchers were reviewed, and reference lists and relevant articles from review articles were also examined. Vertical/intrauterine transmission leads to congenital infection and causes microcephaly and congenital ZIKV syndrome. ZIKV preferentially infects human neural progenitor cells and triggers cell apoptosis. ZIKV RNA has been identified in foetal brain tissue and brains of microcephalic infants who died; amniotic fluid and placentas of pregnant mothers; and umbilical cord, cerebro-spinal fluid and meninges of newborns. The increase in the number of Guillain-Barre syndrome (GBS) cases during the ZIKV outbreak in the Americas provides epidemiological evidence for the link between ZIKV infection and GBS. Less frequently reported ZIKV neurological complications include encephalitis/meningoencephalitis, acute disseminated encephalomyelitis, myelitis, cerebrovascular complications (ischemic infarction; vasculopathy), seizures and encephalopathy, sensory polyneuropathy and sensory neuronopathy. Analysis of GBS incidence could serve as an epidemiological 'marker' or sentinel for ZIKV disease and other neurological complications associated to ZIKV. Expert commentary: An expanding spectrum of neurological complications associated with ZIKV infection is being recognised.

  15. Complications of decorative tattoo.

    Science.gov (United States)

    Shinohara, Michi M

    2016-01-01

    Decorative tattoo is a popular practice that is generally safe when performed in the professional setting but can be associated with a variety of inflammatory, infectious, and neoplastic complications, risks that may be increased with current trends in home tattooing. Modern tattoo inks contain azo dyes and are often of unknown composition and not currently regulated for content or purity. Biopsy of most (if not all) tattoo reactions presenting to the dermatologist is recommended, given recent clusters of nontuberculous mycobacterial infections occurring within tattoo, as well as associations between tattoo reactions and systemic diseases such as sarcoidosis. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Lemierre's Syndrome Complicating Pregnancy

    Directory of Open Access Journals (Sweden)

    M. Thompson

    2007-01-01

    Full Text Available Lemierre's syndrome is an anaerobic suppurative thrombophlebitis involving the internal jugular vein secondary to oropharyngeal infection. There is only one previous case report in pregnancy which was complicated by premature delivery of an infant that suffered significant neurological damage. We present an atypical case diagnosed in the second trimester with a live birth at term. By reporting this case, we hope to increase the awareness of obstetricians to the possibility of Lemierre's syndrome when patients present with signs of unabating oropharyngeal infection and pulmonary symptoms.

  17. [Complications of hemorrhoids].

    Science.gov (United States)

    Slauf, P; Antoš, F; Marx, J

    2014-04-01

    The most common and serious complications of haemorrhoids include perianal thrombosis and incarcerated prolapsed internal haemorrhoids with subsequent thrombosis. They are characterised by severe pain in the perianal region possibly with bleeding. In a short history of the perianal thrombosis, acute surgical incision or excision is indicated, which can result in rapid relief of the painful symptoms. In incarcerated prolapsed internal haemorrhoids, emergency haemorrhoidectomy may also be indicated. Segmental haemorrhoidectomy in the most affected quadrants followed by further elective surgery for haemorrhoids in the next stage is preferred.

  18. Large deviations and idempotent probability

    CERN Document Server

    Puhalskii, Anatolii

    2001-01-01

    In the view of many probabilists, author Anatolii Puhalskii''s research results stand among the most significant achievements in the modern theory of large deviations. In fact, his work marked a turning point in the depth of our understanding of the connections between the large deviation principle (LDP) and well-known methods for establishing weak convergence results.Large Deviations and Idempotent Probability expounds upon the recent methodology of building large deviation theory along the lines of weak convergence theory. The author develops an idempotent (or maxitive) probability theory, introduces idempotent analogues of martingales (maxingales), Wiener and Poisson processes, and Ito differential equations, and studies their properties. The large deviation principle for stochastic processes is formulated as a certain type of convergence of stochastic processes to idempotent processes. The author calls this large deviation convergence.The approach to establishing large deviation convergence uses novel com...

  19. Probability biases as Bayesian inference

    Directory of Open Access Journals (Sweden)

    Andre; C. R. Martins

    2006-11-01

    Full Text Available In this article, I will show how several observed biases in human probabilistic reasoning can be partially explained as good heuristics for making inferences in an environment where probabilities have uncertainties associated to them. Previous results show that the weight functions and the observed violations of coalescing and stochastic dominance can be understood from a Bayesian point of view. We will review those results and see that Bayesian methods should also be used as part of the explanation behind other known biases. That means that, although the observed errors are still errors under the be understood as adaptations to the solution of real life problems. Heuristics that allow fast evaluations and mimic a Bayesian inference would be an evolutionary advantage, since they would give us an efficient way of making decisions. %XX In that sense, it should be no surprise that humans reason with % probability as it has been observed.

  20. Probability matching and strategy availability.

    Science.gov (United States)

    Koehler, Derek J; James, Greta

    2010-09-01

    Findings from two experiments indicate that probability matching in sequential choice arises from an asymmetry in strategy availability: The matching strategy comes readily to mind, whereas a superior alternative strategy, maximizing, does not. First, compared with the minority who spontaneously engage in maximizing, the majority of participants endorse maximizing as superior to matching in a direct comparison when both strategies are described. Second, when the maximizing strategy is brought to their attention, more participants subsequently engage in maximizing. Third, matchers are more likely than maximizers to base decisions in other tasks on their initial intuitions, suggesting that they are more inclined to use a choice strategy that comes to mind quickly. These results indicate that a substantial subset of probability matchers are victims of "underthinking" rather than "overthinking": They fail to engage in sufficient deliberation to generate a superior alternative to the matching strategy that comes so readily to mind.

  1. Probability as a Physical Motive

    Directory of Open Access Journals (Sweden)

    Peter Martin

    2007-04-01

    Full Text Available Recent theoretical progress in nonequilibrium thermodynamics, linking thephysical principle of Maximum Entropy Production (“MEP” to the information-theoretical“MaxEnt” principle of scientific inference, together with conjectures from theoreticalphysics that there may be no fundamental causal laws but only probabilities for physicalprocesses, and from evolutionary theory that biological systems expand “the adjacentpossible” as rapidly as possible, all lend credence to the proposition that probability shouldbe recognized as a fundamental physical motive. It is further proposed that spatial order andtemporal order are two aspects of the same thing, and that this is the essence of the secondlaw of thermodynamics.

  2. Complications associated with orthognathic surgery

    Science.gov (United States)

    2017-01-01

    While most patients undergo orthognathic surgery for aesthetic purposes, aesthetic improvements are most often followed by postoperative functional complications. Therefore, patients must carefully decide whether their purpose of undergoing orthognathic surgery lies on the aesthetic side or the functional side. There is a wide variety of complications associated with orthognathic surgery. There should be a clear distinction between malpractice and complications. Complications can be resolved without any serious problems if the cause is detected early and adequate treatment provided. Oral and maxillofacial surgeons must have a full understanding of the types, causes, and treatment of complications, and should deliver this information to patients who develop these complications. PMID:28280704

  3. Logic, Probability, and Human Reasoning

    Science.gov (United States)

    2015-01-01

    accordingly suggest a way to integrate probability and deduction. The nature of deductive reasoning To be rational is to be able to make deductions...3–6] and they underlie mathematics, science, and tech- nology [7–10]. Plato claimed that emotions upset reason- ing. However, individuals in the grip...fundamental to human rationality . So, if counterexamples to its principal predictions occur, the theory will at least explain its own refutation

  4. Probability Measures on Groups IX

    CERN Document Server

    1989-01-01

    The latest in this series of Oberwolfach conferences focussed on the interplay between structural probability theory and various other areas of pure and applied mathematics such as Tauberian theory, infinite-dimensional rotation groups, central limit theorems, harmonizable processes, and spherical data. Thus it was attended by mathematicians whose research interests range from number theory to quantum physics in conjunction with structural properties of probabilistic phenomena. This volume contains 5 survey articles submitted on special invitation and 25 original research papers.

  5. Probability matching and strategy availability

    OpenAIRE

    J. Koehler, Derek; Koehler, Derek J.; James, Greta

    2010-01-01

    Findings from two experiments indicate that probability matching in sequential choice arises from an asymmetry in strategy availability: The matching strategy comes readily to mind, whereas a superior alternative strategy, maximizing, does not. First, compared with the minority who spontaneously engage in maximizing, the majority of participants endorse maximizing as superior to matching in a direct comparison when both strategies are described. Second, when the maximizing strategy is brought...

  6. CT findings of acute cholecystitis and its complications.

    Science.gov (United States)

    Shakespear, Jonathan S; Shaaban, Akram M; Rezvani, Maryam

    2010-06-01

    The purpose of this article is to describe and illustrate the CT findings of acute cholecystitis and its complications. CT findings suggesting acute cholecystitis should be interpreted with caution and should probably serve as justification for further investigation with abdominal ultrasound. CT has a relatively high negative predictive value, and acute cholecystitis is unlikely in the setting of a negative CT. Complications of acute cholecystitis have a characteristic CT appearance and include necrosis, perforation, abscess formation, intraluminal hemorrhage, and wall emphysema.

  7. Complications of cranioplasty after decompressive craniectomy

    Directory of Open Access Journals (Sweden)

    Maša Glišović

    2015-04-01

    Full Text Available Cranioplasty is a surgical repair of a defect or deformity of a skull with the use of autologous bone or synthetic materials.[4] It usually follows decompressive craniectomy, which is a commonly practiced neurosurgical intervention in patients with raised intracranial pressure unresponsive to other forms of treatment.[1] There are many conditions that may lead to intracranial hypertension, and the goal is to avoid brain necrosis caused by compartment pressure syndrome.[2] Consequently, the extensive use of decompressive craniectomy directly results in more cranioplasties, which sometimes present with unwanted complications.[5] Generally, the occurence of cranioplasty complications is between 16% and 34%.[3] Because of the many indications for craniectomy based on clinical data that speak in its favour, if will probably remain a relatively common neurosurgical intervention also in the future. The frequency of decompressive craniectomy and consequently of cranioplasty requires awareness of the many potential postoperative complications and understanding of its evolution. This article is a review of pathophysiological mechanisms after decompressive craniectomy and cranioplasty, of its complications and factors that potentially contribute to their occurence.

  8. Complications of acromegaly: thyroid and colon.

    Science.gov (United States)

    Tirosh, Amit; Shimon, Ilan

    2017-02-01

    In acromegaly the long-term exposure to high growth hormone (GH) and insulin-like growth factor-1 (IGF-1) levels may result in specific complications in different human organs, including the thyroid gland and the colon. We will review here the evidence available regarding the characteristic thyroid and colon complications in acromegaly. This review summarizes the published data observing noncancerous structural abnormalities (thyroid nodules, colonic polyps) and thyroid and colon cancer in patients diagnosed with acromegaly. Thyroid micro-carcinomas are probably over-diagnosed among acromegalic patients. In regard to colon cancer, there is no sufficient data to suggest that colon cancer risk is higher in acromegaly compared to the general population.

  9. Arterial complications of vascular Ehlers-Danlos syndrome.

    Science.gov (United States)

    Eagleton, Matthew J

    2016-12-01

    Vascular Ehlers-Danlos syndrome (EDS) is a relatively rare genetic syndrome that occurs owing to disorders in the metabolism of fibrillary collagen. These defects affect the soft connective tissues resulting in abnormalities in the skin, joints, hollow organs, and blood vessels. Patients with these defects frequently present at a young age with spontaneous arterial complications involving the medium-sized arteries. Complications involving the hollow organs, such as spontaneous colonic perforation, are observed as well. Given the fragility of the soft tissue, open and endovascular intervention on patients with vascular EDS is fraught with high complication rates. A PubMed search was performed to identify manuscripts published related to vascular EDS. This search included more than 747 articles. These findings were cross-referenced using key terms, including endovascular, embolization, surgery, genetics, pathophysiology, connective tissue disorders, vascular complications, systematic review, type III collagen, and COL3A1. The references in key articles and review articles were evaluated for additional resources not identified in the PubMed search. Care must be taken to balance the risk of intervention vs the risk of continued observation. Life-threatening hemorrhage, however, mandates intervention. With careful, altered approaches to tissue handling, endovascular approaches may provide a safer option for managing the arterial complications observed in patients with vascular EDS. Additional hope may also be found in the use of pharmacologic agents that reduce the incidence and severity of the arterial complications. Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

  10. Two-slit experiment: quantum and classical probabilities

    International Nuclear Information System (INIS)

    Khrennikov, Andrei

    2015-01-01

    Inter-relation between quantum and classical probability models is one of the most fundamental problems of quantum foundations. Nowadays this problem also plays an important role in quantum technologies, in quantum cryptography and the theory of quantum random generators. In this letter, we compare the viewpoint of Richard Feynman that the behavior of quantum particles cannot be described by classical probability theory with the viewpoint that quantum–classical inter-relation is more complicated (cf, in particular, with the tomographic model of quantum mechanics developed in detail by Vladimir Man'ko). As a basic example, we consider the two-slit experiment, which played a crucial role in quantum foundational debates at the beginning of quantum mechanics (QM). In particular, its analysis led Niels Bohr to the formulation of the principle of complementarity. First, we demonstrate that in complete accordance with Feynman's viewpoint, the probabilities for the two-slit experiment have the non-Kolmogorovian structure, since they violate one of basic laws of classical probability theory, the law of total probability (the heart of the Bayesian analysis). However, then we show that these probabilities can be embedded in a natural way into the classical (Kolmogorov, 1933) probability model. To do this, one has to take into account the randomness of selection of different experimental contexts, the joint consideration of which led Feynman to a conclusion about the non-classicality of quantum probability. We compare this embedding of non-Kolmogorovian quantum probabilities into the Kolmogorov model with well-known embeddings of non-Euclidean geometries into Euclidean space (e.g., the Poincaré disk model for the Lobachvesky plane). (paper)

  11. Complications of minimally invasive cosmetic procedures: Prevention and management

    Directory of Open Access Journals (Sweden)

    Lauren L Levy

    2012-01-01

    Full Text Available Over the past decade, facial rejuvenation procedures to circumvent traditional surgery have become increasingly popular. Office-based, minimally invasive procedures can promote a youthful appearance with minimal downtime and low risk of complications. Injectable botulinum toxin (BoNT, soft-tissue fillers, and chemical peels are among the most popular non-invasive rejuvenation procedures, and each has unique applications for improving facial aesthetics. Despite the simplicity and reliability of office-based procedures, complications can occur even with an astute and experienced injector. The goal of any procedure is to perform it properly and safely; thus, early recognition of complications when they do occur is paramount in dictating prevention of long-term sequelae. The most common complications from BoNT and soft-tissue filler injection are bruising, erythema and pain. With chemical peels, it is not uncommon to have erythema, irritation and burning. Fortunately, these side effects are normally transient and have simple remedies. More serious complications include muscle paralysis from BoNT, granuloma formation from soft-tissue filler placement and scarring from chemical peels. Thankfully, these complications are rare and can be avoided with excellent procedure technique, knowledge of facial anatomy, proper patient selection, and appropriate pre- and post-skin care. This article reviews complications of office-based, minimally invasive procedures, with emphasis on prevention and management. Practitioners providing these treatments should be well versed in this subject matter in order to deliver the highest quality care.

  12. Radiobiology in clinical radiation therapy - Part III: Normal tissue damage

    International Nuclear Information System (INIS)

    Travis, Elizabeth L.

    1996-01-01

    relationship of tissue architecture to radiation-induced damage and the available clinical and experimental data which demonstrate volume effects as well as those factors which complicate efforts to estimate normal tissue complication probabilities

  13. Long term complications of diabetes

    Science.gov (United States)

    ... medlineplus.gov/ency/patientinstructions/000327.htm Long-term complications of diabetes To use the sharing features on this page, ... other tests. All these may help you keep complications of diabetes away. You will need to check your blood ...

  14. Ligament Tissue Engineering

    OpenAIRE

    Khan, Wasim Sardar

    2016-01-01

    Ligaments are commonly injured in the knee joint, and have a poor capacity for healing due to their relative avascularity. Ligament reconstruction is well established for injuries such as anterior cruciate ligament rupture, however the use of autografts and allografts for ligament reconstruction are associated with complications, and outcomes are variable. Ligament tissue engineering using stem cells, growth factors and scaffolds is a novel technique that has the potential to provide an unlim...

  15. Complication of radiation therapy

    International Nuclear Information System (INIS)

    Imajo, Yoshinari; Suematsu, Toru; Narabayashi, Isamu; Gose, Kyuhei; Takimoto, Saeko

    1984-01-01

    The radiation pneumonitis is a major complication for patients recieving thoracic irradiation. This report describe the radiographic recognition, pathological change and imapired pulmonary functions of radiation pneumonitis. The 57 patients with lung cancer treated with radiation are analyzed on the pneumonitis by chest X-P. Among these, 50 patients (88%) develop radiation pneumonitis. Repeated CT scans give more detailed information than conventional radiograms as to exdative changes. The pathological analysis are made on the 35 patients of which affected lungs are resected after pre-operative irradiation. Three phases are recognized in the evolution of pneumonitis, the ongestive, the degenerative, and the fibrotic. Adding to the morphorogical damage, pulmonary functions also detrieorate both in ventilation and perfusion scans. (author)

  16. Tattoo complaints and complications

    DEFF Research Database (Denmark)

    Serup, Jørgen; Carlsen, Katrina Hutton; Sepehri, Mitra

    2015-01-01

    Tattoos cause a broad range of clinical problems. Mild complaints, especially sensitivity to sun, are very common and seen in 1/5 of cases. Medical complications are dominated by allergy to tattoo pigment haptens or haptens generated in the skin, especially in red tattoos but also in blue and green...... tattoos. Symptoms are major and can be compared to cumbersome pruritic skin diseases. Tattoo allergies and local reactions show distinct clinical manifestations, with plaque-like, excessive hyperkeratotic, ulcero-necrotic, lymphopathic, neuro-sensory, and scar patterns. Reactions in black tattoos......) transferred by tattooing remain a significant risk needing active prevention. It is noteworthy that cancer arising in tattoos, in regional lymph nodes, and in other organs due to tattoo pigments and ingredients has not been detected or noted as a significant clinical problem hitherto, despite millions...

  17. Neurologic Complications of Transplantation.

    Science.gov (United States)

    Dhar, Rajat

    2018-02-01

    Neurologic disturbances including encephalopathy, seizures, and focal deficits complicate the course 10-30% of patients undergoing organ or stem cell transplantation. While much or this morbidity is multifactorial and often associated with extra-cerebral dysfunction (e.g., graft dysfunction, metabolic derangements), immunosuppressive drugs also contribute significantly. This can either be through direct toxicity (e.g., posterior reversible encephalopathy syndrome from calcineurin inhibitors such as tacrolimus in the acute postoperative period) or by facilitating opportunistic infections in the months after transplantation. Other neurologic syndromes such as akinetic mutism and osmotic demyelination may also occur. While much of this neurologic dysfunction may be reversible if related to metabolic factors or drug toxicity (and the etiology is recognized and reversed), cases of multifocal cerebral infarction, hemorrhage, or infection may have poor outcomes. As transplant patients survive longer, delayed infections (such as progressive multifocal leukoencephalopathy) and post-transplant malignancies are increasingly reported.

  18. [Biometric bases: basic concepts of probability calculation].

    Science.gov (United States)

    Dinya, E

    1998-04-26

    The author gives or outline of the basic concepts of probability theory. The bases of the event algebra, definition of the probability, the classical probability model and the random variable are presented.

  19. Microvascular complications associated with injection of cosmetic facelift dermal fillers

    Science.gov (United States)

    Yousefi, Siavash; Prendes, Mark; Chang, Shu-Hong; Wang, Ruikang K.

    2015-02-01

    Minimally-invasive cosmetic surgeries such as injection of subdermal fillers have become very popular in the past decade. Although rare, some complications may follow injections such as tissue necrosis and even blindness. There exist two hypothesis regarding source of these complications both of which include microvasculature. The first hypothesis is that fillers in between the tissue structures and compress microvasculature that causes blockage of tissue neutrition and oxygen exchange in the tissue. In another theory, it is hypothesized that fillers move inside major arteries and block the arteries/veins. In this paper, we study these hypotheses using optical coherence tomography and optical microangiography technologies with different hyaluronic-acid fillers in a mouse ear model. Based on our observations, the fillers eventually block arteries/veins if injected directly into them that eventually causes tissue necrosis.

  20. Probability for Weather and Climate

    Science.gov (United States)

    Smith, L. A.

    2013-12-01

    Over the last 60 years, the availability of large-scale electronic computers has stimulated rapid and significant advances both in meteorology and in our understanding of the Earth System as a whole. The speed of these advances was due, in large part, to the sudden ability to explore nonlinear systems of equations. The computer allows the meteorologist to carry a physical argument to its conclusion; the time scales of weather phenomena then allow the refinement of physical theory, numerical approximation or both in light of new observations. Prior to this extension, as Charney noted, the practicing meteorologist could ignore the results of theory with good conscience. Today, neither the practicing meteorologist nor the practicing climatologist can do so, but to what extent, and in what contexts, should they place the insights of theory above quantitative simulation? And in what circumstances can one confidently estimate the probability of events in the world from model-based simulations? Despite solid advances of theory and insight made possible by the computer, the fidelity of our models of climate differs in kind from the fidelity of models of weather. While all prediction is extrapolation in time, weather resembles interpolation in state space, while climate change is fundamentally an extrapolation. The trichotomy of simulation, observation and theory which has proven essential in meteorology will remain incomplete in climate science. Operationally, the roles of probability, indeed the kinds of probability one has access too, are different in operational weather forecasting and climate services. Significant barriers to forming probability forecasts (which can be used rationally as probabilities) are identified. Monte Carlo ensembles can explore sensitivity, diversity, and (sometimes) the likely impact of measurement uncertainty and structural model error. The aims of different ensemble strategies, and fundamental differences in ensemble design to support of

  1. Probability, Statistics, and Stochastic Processes

    CERN Document Server

    Olofsson, Peter

    2012-01-01

    This book provides a unique and balanced approach to probability, statistics, and stochastic processes.   Readers gain a solid foundation in all three fields that serves as a stepping stone to more advanced investigations into each area.  The Second Edition features new coverage of analysis of variance (ANOVA), consistency and efficiency of estimators, asymptotic theory for maximum likelihood estimators, empirical distribution function and the Kolmogorov-Smirnov test, general linear models, multiple comparisons, Markov chain Monte Carlo (MCMC), Brownian motion, martingales, and

  2. Probability, statistics, and computational science.

    Science.gov (United States)

    Beerenwinkel, Niko; Siebourg, Juliane

    2012-01-01

    In this chapter, we review basic concepts from probability theory and computational statistics that are fundamental to evolutionary genomics. We provide a very basic introduction to statistical modeling and discuss general principles, including maximum likelihood and Bayesian inference. Markov chains, hidden Markov models, and Bayesian network models are introduced in more detail as they occur frequently and in many variations in genomics applications. In particular, we discuss efficient inference algorithms and methods for learning these models from partially observed data. Several simple examples are given throughout the text, some of which point to models that are discussed in more detail in subsequent chapters.

  3. Sensitivity analysis using probability bounding

    International Nuclear Information System (INIS)

    Ferson, Scott; Troy Tucker, W.

    2006-01-01

    Probability bounds analysis (PBA) provides analysts a convenient means to characterize the neighborhood of possible results that would be obtained from plausible alternative inputs in probabilistic calculations. We show the relationship between PBA and the methods of interval analysis and probabilistic uncertainty analysis from which it is jointly derived, and indicate how the method can be used to assess the quality of probabilistic models such as those developed in Monte Carlo simulations for risk analyses. We also illustrate how a sensitivity analysis can be conducted within a PBA by pinching inputs to precise distributions or real values

  4. Lectures on probability and statistics

    International Nuclear Information System (INIS)

    Yost, G.P.

    1984-09-01

    These notes are based on a set of statistics lectures delivered at Imperial College to the first-year postgraduate students in High Energy Physics. They are designed for the professional experimental scientist. We begin with the fundamentals of probability theory, in which one makes statements about the set of possible outcomes of an experiment, based upon a complete a priori understanding of the experiment. For example, in a roll of a set of (fair) dice, one understands a priori that any given side of each die is equally likely to turn up. From that, we can calculate the probability of any specified outcome. We finish with the inverse problem, statistics. Here, one begins with a set of actual data (e.g., the outcomes of a number of rolls of the dice), and attempts to make inferences about the state of nature which gave those data (e.g., the likelihood of seeing any given side of any given die turn up). This is a much more difficult problem, of course, and one's solutions often turn out to be unsatisfactory in one respect or another

  5. Intraoperative and early postoperative complications of manual sutureless cataract extraction.

    Science.gov (United States)

    Iqbal, Yasir; Zia, Sohail; Baig Mirza, Aneeq Ullah

    2014-04-01

    To determine the intraoperative and early postoperative complications of manual sutureless cataract extraction. Case series. Redo Eye Hospital, Rawalpindi, Pakistan, from January 2009 to December 2010. Three hundred patients of cataract through purposive non-probability sampling were selected. The patients underwent manual sutureless cataract surgery (MSCS) by single experienced surgeon and intraoperative complications were documented. The surgical technique was modified to deal with any intraoperative complications accordingly. Patients were examined on the first postoperative day and on the first postoperative week for any postoperative complications. The data was entered in Statistical Package for Social Sciences (SPSS) version 13.0 and the results were calculated in frequencies. Among the 300 cases, 81.3% surgeries went uneventful whereas 18.6% had some complication. The common intraoperative complications were superior button-hole formation in 5%; posterior capsular rent in 5% and premature entry with iris prolapse in 3% cases. Postoperatively, the commonly encountered complications were striate keratopathy in 9.6% and hyphema 9%. At first week follow-up, 4% had striate keratopathy and 0.6% had hyphema. Striate keratopathy resolved with topical medication on subsequent follow-up. A total of 9 cases (3%) underwent second surgery: 2 cases for lens matter wash, 2 cases for hyphema and 5 cases needed suturing of wound for shallow anterior chamber due to wound leak. Superior button-hole formation, posterior capsular rent and premature entry were the common intraoperative complications of MSCS whereas the common early postoperative complications were striate keratopathy and hyphema.

  6. On the Inclusion of Short-distance Bystander Effects into a Logistic Tumor Control Probability Model.

    Science.gov (United States)

    Tempel, David G; Brodin, N Patrik; Tomé, Wolfgang A

    2018-01-01

    Currently, interactions between voxels are neglected in the tumor control probability (TCP) models used in biologically-driven intensity-modulated radiotherapy treatment planning. However, experimental data suggests that this may not always be justified when bystander effects are important. We propose a model inspired by the Ising model, a short-range interaction model, to investigate if and when it is important to include voxel to voxel interactions in biologically-driven treatment planning. This Ising-like model for TCP is derived by first showing that the logistic model of tumor control is mathematically equivalent to a non-interacting Ising model. Using this correspondence, the parameters of the logistic model are mapped to the parameters of an Ising-like model and bystander interactions are introduced as a short-range interaction as is the case for the Ising model. As an example, we apply the model to study the effect of bystander interactions in the case of radiation therapy for prostate cancer. The model shows that it is adequate to neglect bystander interactions for dose distributions that completely cover the treatment target and yield TCP estimates that lie in the shoulder of the dose response curve. However, for dose distributions that yield TCP estimates that lie on the steep part of the dose response curve or for inhomogeneous dose distributions having significant hot and/or cold regions, bystander effects may be important. Furthermore, the proposed model highlights a previously unexplored and potentially fruitful connection between the fields of statistical mechanics and tumor control probability/normal tissue complication probability modeling.

  7. Complications of acucise endopyelotomy.

    Science.gov (United States)

    Kim, F J; Herrell, S D; Jahoda, A E; Albala, D M

    1998-10-01

    Endoscopic management of ureteropelvic junction (UPJ) obstruction has a success rate of 80% to 86%. We have been performing a ureteral cutting balloon procedure under fluoroscopic control (Acucise endopyelotomy) for UPJ obstruction at Loyola University Medical Center since 1991. The overall success rate in 77 patients was 78%. All patients had a preoperative intravenous urogram or a retrograde pyelogram, but none had vascular imaging studies. Acucise endopyelotomy consisted of a posterolateral incision of the UPJ and placement of an endopyelotomy or double-J stent. Foley catheter placement at the end of the procedure demonstrated significant gross hematuria in three patients (4%). All three remained hemodynamically stable but with significant drops in postprocedure hemoglobin levels, which necessitated blood transfusion. Aggressive management included angiographic studies and embolization of lower-pole branching arteries in two patients (3%). One patient stopped bleeding after being given two units of blood. None of the patients required an open exploratory procedure. Although the risk of vascular injury is low with Acucise endopyelotomy, prolonged postoperative gross hematuria does mandate investigation and observation. Angiographic embolization appears to be the therapeutic modality of choice for patients with hemorrhagic complications after an Acucise endopyelotomy.

  8. Renal complications of anaesthesia.

    Science.gov (United States)

    McKinlay, J; Tyson, E; Forni, L G

    2018-01-01

    Peri-operative acute kidney injury is common, accounting for 30-40% of all in-hospital cases of acute kidney injury. It is associated with clinically significant morbidity and mortality even with what was hitherto regarded as relatively trivial increases in serum creatinine, and carries over a 12-fold relative risk of death following major abdominal surgery. Comorbid conditions such as diabetes, hypertension, liver disease and particularly pre-existing chronic kidney disease, as well as the type and urgency of surgery, are major risk factors for the development of postoperative acute kidney injury. As yet, there are no specific treatment options for the injured kidney, although there are several modifiable risk factors of which the anaesthetist should be aware. As well as the avoidance of potential nephrotoxins and appropriate volume balance, optimal anaesthetic management should aim to reduce the risk of postoperative renal complications. This may include careful ventilatory management and blood pressure control, as well as appropriate analgesic strategies. The choice of anaesthetic agent may also influence renal outcomes. Rather than concentrate on the classical management of acute kidney injury, this review focuses on the potential development of acute kidney injury peri-operatively, and the means by which this may be ameliorated. © 2018 The Association of Anaesthetists of Great Britain and Ireland.

  9. Probability theory a comprehensive course

    CERN Document Server

    Klenke, Achim

    2014-01-01

    This second edition of the popular textbook contains a comprehensive course in modern probability theory. Overall, probabilistic concepts play an increasingly important role in mathematics, physics, biology, financial engineering and computer science. They help us in understanding magnetism, amorphous media, genetic diversity and the perils of random developments at financial markets, and they guide us in constructing more efficient algorithms.   To address these concepts, the title covers a wide variety of topics, many of which are not usually found in introductory textbooks, such as:   • limit theorems for sums of random variables • martingales • percolation • Markov chains and electrical networks • construction of stochastic processes • Poisson point process and infinite divisibility • large deviation principles and statistical physics • Brownian motion • stochastic integral and stochastic differential equations. The theory is developed rigorously and in a self-contained way, with the c...

  10. Early bowel complications following radiotherapy of uterine cervix carcinoma

    International Nuclear Information System (INIS)

    Kim, Won Dong

    1999-01-01

    This study evaluated early bowel complications in cervix cancer patients, following external radiotherapy (ERT) and high dose rate intracavitary radiation (HDR ICR). Factors affecting the risk of developing early bowel complications and its incidence are analyzed and discussed. The study is the retrospective review of 66 patients who received radiotherapy at Chungbuk National University Hospital from April 1994 to December 1998. The patients underwent 41.4 or 50.4 Gy ERT according to FIGO stage and tumor size, then A point dose was boosted to 71.4 or 74.4 Gy using a remotely controlled after loading Buchler HDR ICR. The EORTC/RTOG morbidity criteria were used to grade early bowel complications, which are valid from day 1, the commencement of therapy, through day 90. The actuarial incidence, severity of complications were investigated and clinical pretreatment factors relevant to complications were found through univariate (Wilcoxon) and multivariate (Cox proportional hazard model) analysis. Of the 66 patients, 30 patients (46%) developed early bowel complications; 25 patients (38%) with grade 1 or 2, 4 patients (6%) with grade 3 and 1 patient (2%) with grade 4. The complications usually began to occur 3 weeks after the commencement of radiotherapy. The actuarial incidence of early bowel complications was 41% at 10 weeks. The early bowel complications were associated significantly with an old age and a history of previous abdomino-pelvic surgery. All three patients who had a protracted overall treatment time (about 2 weeks) due to severe bowel complication, suffered from pelvic recurrences. Forty six percent of patients experienced early bowel complications, most of which were grade 1 or 2 and relieved spontaneously or by medication. The patients with an old age or a previous surgery have a high probability of early complications and they may be less compliant with planned radiotherapy. So more careful precaution is necessary for these patients

  11. Chest complication after abdominal surgery

    International Nuclear Information System (INIS)

    Koh, B. H.; Choi, J. Y.; Hahm, C. K.; Kang, S. R.

    1981-01-01

    In spite of many advances in medicine, anesthetic technique and surgical managements, pulmonary problems are the most frequent postoperative complications, particularly after abdominal surgery. As postoperative pulmonary complications, atelectasis, pleural effusion, pneumonia, chronic bronchitis and lung abscess can be occurred. This study include evaluation of chest films of 2006 patients (927 male, 1079 female), who had been operated abdominal surgery from Jan. 1979 to June, 1980 in the Hanyang university hospital. The results were as follows: 1. 70 cases out of total 2006 cases (3.5%) developed postoperative chest complications, 51 cases (5.5%) in male, 19 cases (1.8%) in female. 2. The complication rate was increased according to the increase of age. The incidence of the postoperative complications over 40 years of age was higher than the overall average complications rate. 3. The most common postoperative pulmonary complication was pleural effusion, next pneumonia, atelectasis and pulmonary edema respectively. 4. The complication rate of the group of upper abdominal surgery is much higher than the group of lower abdominal surgery. 5. Complication rate was increased according to increase of the duration of operation. 6. There were significant correlations between the operation site and side of the complicated hemithorax

  12. Excluding joint probabilities from quantum theory

    Science.gov (United States)

    Allahverdyan, Armen E.; Danageozian, Arshag

    2018-03-01

    Quantum theory does not provide a unique definition for the joint probability of two noncommuting observables, which is the next important question after the Born's probability for a single observable. Instead, various definitions were suggested, e.g., via quasiprobabilities or via hidden-variable theories. After reviewing open issues of the joint probability, we relate it to quantum imprecise probabilities, which are noncontextual and are consistent with all constraints expected from a quantum probability. We study two noncommuting observables in a two-dimensional Hilbert space and show that there is no precise joint probability that applies for any quantum state and is consistent with imprecise probabilities. This contrasts with theorems by Bell and Kochen-Specker that exclude joint probabilities for more than two noncommuting observables, in Hilbert space with dimension larger than two. If measurement contexts are included into the definition, joint probabilities are not excluded anymore, but they are still constrained by imprecise probabilities.

  13. Probability theory and mathematical statistics for engineers

    CERN Document Server

    Pugachev, V S

    1984-01-01

    Probability Theory and Mathematical Statistics for Engineers focuses on the concepts of probability theory and mathematical statistics for finite-dimensional random variables.The publication first underscores the probabilities of events, random variables, and numerical characteristics of random variables. Discussions focus on canonical expansions of random vectors, second-order moments of random vectors, generalization of the density concept, entropy of a distribution, direct evaluation of probabilities, and conditional probabilities. The text then examines projections of random vector

  14. Introduction to probability theory with contemporary applications

    CERN Document Server

    Helms, Lester L

    2010-01-01

    This introduction to probability theory transforms a highly abstract subject into a series of coherent concepts. Its extensive discussions and clear examples, written in plain language, expose students to the rules and methods of probability. Suitable for an introductory probability course, this volume requires abstract and conceptual thinking skills and a background in calculus.Topics include classical probability, set theory, axioms, probability functions, random and independent random variables, expected values, and covariance and correlations. Additional subjects include stochastic process

  15. Tissue engineering

    CERN Document Server

    Fisher, John P; Bronzino, Joseph D

    2007-01-01

    Increasingly viewed as the future of medicine, the field of tissue engineering is still in its infancy. As evidenced in both the scientific and popular press, there exists considerable excitement surrounding the strategy of regenerative medicine. To achieve its highest potential, a series of technological advances must be made. Putting the numerous breakthroughs made in this field into a broad context, Tissue Engineering disseminates current thinking on the development of engineered tissues. Divided into three sections, the book covers the fundamentals of tissue engineering, enabling technologies, and tissue engineering applications. It examines the properties of stem cells, primary cells, growth factors, and extracellular matrix as well as their impact on the development of tissue engineered devices. Contributions focus on those strategies typically incorporated into tissue engineered devices or utilized in their development, including scaffolds, nanocomposites, bioreactors, drug delivery systems, and gene t...

  16. Complications in ankle fracture surgery

    OpenAIRE

    Ovaska, Mikko

    2015-01-01

    Mikko Ovaska. Complications in Ankle Fracture Surgery. Helsinki Bone and Joint Research Group, Department of Orthopaedic Surgery and Traumatology, Faculty of Medicine, University of Helsinki, Finland. Helsinki 2014. Ankle fractures are among the most frequently encountered surgically treated fractures. The operative treatment of this fracture may be associated with several complications. The most frequently encountered complications are related wound healing, and deep infection may have d...

  17. Minimizing complications of ultrasound-assisted lipoplasty: an initial experience with no related complications.

    Science.gov (United States)

    Tebbetts, J B

    1998-10-01

    Numerous complications and increased operating times were reported with ultrasonically assisted lipoplasty in the first several months after introduction of the technology in the United States. The purpose of this study was to review early reported complications and management regimens, evaluate possible causes of problems, and apply indications and techniques to attempt to minimize complications during an initial experience with this technique beginning in January of 1997. Seven specific indications and modifications of existing techniques were developed and applied to an initial clinical series of 70 consecutive patients who underwent ultrasound-assisted suction lipoplasty between January 10, 1997, and August 1, 1997. Follow-up ranged from 1 to 7 months. No perioperative or postoperative complication occurred in any patient in this series. In this series of ultrasound-assisted lipoplasty cases, application of the following criteria resulted in a series of 70 patients with 1 to 7-month follow-up without complications: (1) selecting patients with well localized fat deposits who were no more than 20 percent above their ideal body weight; (2) infusing a solution of Ringer's Lactate containing 1 cc of 1:1000 epinephrine per 1000 cc into the area of fat removal, stopping infusion when the tissues first become firm, not infusing to marked tissue turgor or skin induration; (3) restricting the level of energy application to a minimum of 1 cm from the undersurface of the dermis; (4) limiting ultrasonic energy application in each area to approximately 1 minute per estimated 100 cc of total aspirate in a wet to superwet environment; (5) not performing ultrasound-assisted lipoplasty in the same area as another procedure that could potentially compromise tissue vascularity; (6) using a Lysonix 2000 generator and 5-mm golf tee tip probe at a power setting of 8 to apply ultrasonic energy to the area of fat removal, ceasing energy application when tissue resistance to the passage

  18. K-forbidden transition probabilities

    International Nuclear Information System (INIS)

    Saitoh, T.R.; Sletten, G.; Bark, R.A.; Hagemann, G.B.; Herskind, B.; Saitoh-Hashimoto, N.; Tsukuba Univ., Ibaraki

    2000-01-01

    Reduced hindrance factors of K-forbidden transitions are compiled for nuclei with A∝180 where γ-vibrational states are observed. Correlations between these reduced hindrance factors and Coriolis forces, statistical level mixing and γ-softness have been studied. It is demonstrated that the K-forbidden transition probabilities are related to γ-softness. The decay of the high-K bandheads has been studied by means of the two-state mixing, which would be induced by the γ-softness, with the use of a number of K-forbidden transitions compiled in the present work, where high-K bandheads are depopulated by both E2 and ΔI=1 transitions. The validity of the two-state mixing scheme has been examined by using the proposed identity of the B(M1)/B(E2) ratios of transitions depopulating high-K bandheads and levels of low-K bands. A break down of the identity might indicate that other levels would mediate transitions between high- and low-K states. (orig.)

  19. Direct probability mapping of contaminants

    International Nuclear Information System (INIS)

    Rautman, C.A.

    1993-01-01

    Exhaustive characterization of a contaminated site is a physical and practical impossibility. Descriptions of the nature, extent, and level of contamination, as well as decisions regarding proposed remediation activities, must be made in a state of uncertainty based upon limited physical sampling. Geostatistical simulation provides powerful tools for investigating contaminant levels, and in particular, for identifying and using the spatial interrelationships among a set of isolated sample values. This additional information can be used to assess the likelihood of encountering contamination at unsampled locations and to evaluate the risk associated with decisions to remediate or not to remediate specific regions within a site. Past operation of the DOE Feed Materials Production Center has contaminated a site near Fernald, Ohio, with natural uranium. Soil geochemical data have been collected as part of the Uranium-in-Soils Integrated Demonstration Project. These data have been used to construct a number of stochastic images of potential contamination for parcels approximately the size of a selective remediation unit. Each such image accurately reflects the actual measured sample values, and reproduces the univariate statistics and spatial character of the extant data. Post-processing of a large number of these equally likely, statistically similar images produces maps directly showing the probability of exceeding specified levels of contamination. Evaluation of the geostatistical simulations can yield maps representing the expected magnitude of the contamination for various regions and other information that may be important in determining a suitable remediation process or in sizing equipment to accomplish the restoration

  20. Psychophysics of the probability weighting function

    Science.gov (United States)

    Takahashi, Taiki

    2011-03-01

    A probability weighting function w(p) for an objective probability p in decision under risk plays a pivotal role in Kahneman-Tversky prospect theory. Although recent studies in econophysics and neuroeconomics widely utilized probability weighting functions, psychophysical foundations of the probability weighting functions have been unknown. Notably, a behavioral economist Prelec (1998) [4] axiomatically derived the probability weighting function w(p)=exp(-() (01e)=1e,w(1)=1), which has extensively been studied in behavioral neuroeconomics. The present study utilizes psychophysical theory to derive Prelec's probability weighting function from psychophysical laws of perceived waiting time in probabilistic choices. Also, the relations between the parameters in the probability weighting function and the probability discounting function in behavioral psychology are derived. Future directions in the application of the psychophysical theory of the probability weighting function in econophysics and neuroeconomics are discussed.

  1. Incidence Probability of Delayed Health Consequences of the Chernobyl Accident

    International Nuclear Information System (INIS)

    Abdel-Ghani, A.H.; El-Naggar, A.M.; El-Kadi, A.A.

    2000-01-01

    During the first international Conference on the long -term consequences of the Chernobyl disaster in 1995 at Kiev, and also during the 1996 International Conference at Vienna, Summing up the consequences of the Chernobyl accident, the data regarding the delayed health consequences were mainly related to thyroid cancer, hereditary disorders, general morbidity, mortality and psychological disturbances. Contrary to expectations, the incidences of Leukemia and Soft Tissue tumors were similar to the spontaneous incident. The expected delayed effects, however, among the accident survivors, the liquidators and populations resident in contaminated areas would show higher incidence probability to Leukemia. These population groups have been continuously exposed to low level radiation both externally and internally. Application of the new ICRP concept of radiation-induced Detriment, and the Nominal Probability Coefficient for Cancer and hereditary effects for both workers and populations are used as the rationale to calculate the incidence probability of occurrence of delayed health effects of the Chernobyl accidents

  2. Embolis cutis medicamentosa, a rare preventable iatrogenic complication

    Directory of Open Access Journals (Sweden)

    Manjunath Kavya,

    2015-07-01

    Full Text Available Embolis cutis medicamentosa is an uncommon iatrogenic complication characterised by variable degree of skin and tissue necrosis, likely to follow intramuscular injection. Intense pain and purplish discoloration of overlying skin, with or without reticulate pattern subsequently followed by tissue necrosis and scarring is highly specific for this syndrome. It has also been reported following intravenous, intra-articular and subcutaneous injections. Herein we are reporting two cases of this rare preventable entity.

  3. THE BLACK HOLE FORMATION PROBABILITY

    Energy Technology Data Exchange (ETDEWEB)

    Clausen, Drew; Piro, Anthony L.; Ott, Christian D., E-mail: dclausen@tapir.caltech.edu [TAPIR, Walter Burke Institute for Theoretical Physics, California Institute of Technology, Mailcode 350-17, Pasadena, CA 91125 (United States)

    2015-02-01

    A longstanding question in stellar evolution is which massive stars produce black holes (BHs) rather than neutron stars (NSs) upon death. It has been common practice to assume that a given zero-age main sequence (ZAMS) mass star (and perhaps a given metallicity) simply produces either an NS or a BH, but this fails to account for a myriad of other variables that may effect this outcome, such as spin, binarity, or even stochastic differences in the stellar structure near core collapse. We argue that instead a probabilistic description of NS versus BH formation may be better suited to account for the current uncertainties in understanding how massive stars die. We present an initial exploration of the probability that a star will make a BH as a function of its ZAMS mass, P {sub BH}(M {sub ZAMS}). Although we find that it is difficult to derive a unique P {sub BH}(M {sub ZAMS}) using current measurements of both the BH mass distribution and the degree of chemical enrichment by massive stars, we demonstrate how P {sub BH}(M {sub ZAMS}) changes with these various observational and theoretical uncertainties. We anticipate that future studies of Galactic BHs and theoretical studies of core collapse will refine P {sub BH}(M {sub ZAMS}) and argue that this framework is an important new step toward better understanding BH formation. A probabilistic description of BH formation will be useful as input for future population synthesis studies that are interested in the formation of X-ray binaries, the nature and event rate of gravitational wave sources, and answering questions about chemical enrichment.

  4. THE BLACK HOLE FORMATION PROBABILITY

    International Nuclear Information System (INIS)

    Clausen, Drew; Piro, Anthony L.; Ott, Christian D.

    2015-01-01

    A longstanding question in stellar evolution is which massive stars produce black holes (BHs) rather than neutron stars (NSs) upon death. It has been common practice to assume that a given zero-age main sequence (ZAMS) mass star (and perhaps a given metallicity) simply produces either an NS or a BH, but this fails to account for a myriad of other variables that may effect this outcome, such as spin, binarity, or even stochastic differences in the stellar structure near core collapse. We argue that instead a probabilistic description of NS versus BH formation may be better suited to account for the current uncertainties in understanding how massive stars die. We present an initial exploration of the probability that a star will make a BH as a function of its ZAMS mass, P BH (M ZAMS ). Although we find that it is difficult to derive a unique P BH (M ZAMS ) using current measurements of both the BH mass distribution and the degree of chemical enrichment by massive stars, we demonstrate how P BH (M ZAMS ) changes with these various observational and theoretical uncertainties. We anticipate that future studies of Galactic BHs and theoretical studies of core collapse will refine P BH (M ZAMS ) and argue that this framework is an important new step toward better understanding BH formation. A probabilistic description of BH formation will be useful as input for future population synthesis studies that are interested in the formation of X-ray binaries, the nature and event rate of gravitational wave sources, and answering questions about chemical enrichment

  5. The Black Hole Formation Probability

    Science.gov (United States)

    Clausen, Drew; Piro, Anthony L.; Ott, Christian D.

    2015-02-01

    A longstanding question in stellar evolution is which massive stars produce black holes (BHs) rather than neutron stars (NSs) upon death. It has been common practice to assume that a given zero-age main sequence (ZAMS) mass star (and perhaps a given metallicity) simply produces either an NS or a BH, but this fails to account for a myriad of other variables that may effect this outcome, such as spin, binarity, or even stochastic differences in the stellar structure near core collapse. We argue that instead a probabilistic description of NS versus BH formation may be better suited to account for the current uncertainties in understanding how massive stars die. We present an initial exploration of the probability that a star will make a BH as a function of its ZAMS mass, P BH(M ZAMS). Although we find that it is difficult to derive a unique P BH(M ZAMS) using current measurements of both the BH mass distribution and the degree of chemical enrichment by massive stars, we demonstrate how P BH(M ZAMS) changes with these various observational and theoretical uncertainties. We anticipate that future studies of Galactic BHs and theoretical studies of core collapse will refine P BH(M ZAMS) and argue that this framework is an important new step toward better understanding BH formation. A probabilistic description of BH formation will be useful as input for future population synthesis studies that are interested in the formation of X-ray binaries, the nature and event rate of gravitational wave sources, and answering questions about chemical enrichment.

  6. Tissue types (image)

    Science.gov (United States)

    ... are 4 basic types of tissue: connective tissue, epithelial tissue, muscle tissue, and nervous tissue. Connective tissue supports ... binds them together (bone, blood, and lymph tissues). Epithelial tissue provides a covering (skin, the linings of the ...

  7. Coloseminal fistula complicating sigmoid diverticulitis.

    Science.gov (United States)

    Barret, Maximilien; Cuenod, Charles-André; Jian, Raymond; Cellier, Christophe; Berger, Anne

    2014-01-01

    We report on a 32-year-old man with a history of chronic lower abdominal pain and urogenital symptoms, leading to the diagnosis of coloseminal fistula complicating diverticular disease. We reviewed the literature on this rare clinical entity and would like to stress the role of pelvic imaging with rectal contrast to investigate complicated forms of diverticular disease. 2014 S. Karger AG, Basel.

  8. Pulmonary complications in neurosurgical patients

    Directory of Open Access Journals (Sweden)

    Randeep Guleria

    2012-01-01

    Full Text Available Pulmonary complications are a major cause of morbidity and mortality in neurosurgical patients. The common pulmonary complications in neurosurgical patients include pneumonia, postoperative atelectasis, respiratory failure, pulmonary embolism, and neurogenic pulmonary edema. Postoperative lung expansion strategies have been shown to be useful in prevention of the postoperative complications in surgical patients. Low tidal volume ventilation should be used in patients who develop acute respiratory distress syndrome. An antibiotic use policy should be put in practice depending on the local patterns of antimicrobial resistance in the hospital. Thromboprophylactic strategies should be used in nonambulatory patients. Meticulous attention should be paid to infection control with a special emphasis on hand-washing practices. Prevention and timely management of these complications can help to decrease the morbidity and mortality associated with pulmonary complications.

  9. Foundations of the theory of probability

    CERN Document Server

    Kolmogorov, AN

    2018-01-01

    This famous little book remains a foundational text for the understanding of probability theory, important both to students beginning a serious study of probability and to historians of modern mathematics. 1956 second edition.

  10. The Probability Distribution for a Biased Spinner

    Science.gov (United States)

    Foster, Colin

    2012-01-01

    This article advocates biased spinners as an engaging context for statistics students. Calculating the probability of a biased spinner landing on a particular side makes valuable connections between probability and other areas of mathematics. (Contains 2 figures and 1 table.)

  11. Conditional Probability Modulates Visual Search Efficiency

    Directory of Open Access Journals (Sweden)

    Bryan eCort

    2013-10-01

    Full Text Available We investigated the effects of probability on visual search. Previous work has shown that people can utilize spatial and sequential probability information to improve target detection. We hypothesized that performance improvements from probability information would extend to the efficiency of visual search. Our task was a simple visual search in which the target was always present among a field of distractors, and could take one of two colors. The absolute probability of the target being either color was 0.5; however, the conditional probability – the likelihood of a particular color given a particular combination of two cues – varied from 0.1 to 0.9. We found that participants searched more efficiently for high conditional probability targets and less efficiently for low conditional probability targets, but only when they were explicitly informed of the probability relationship between cues and target color.

  12. Analytic Neutrino Oscillation Probabilities in Matter: Revisited

    Energy Technology Data Exchange (ETDEWEB)

    Parke, Stephen J. [Fermilab; Denton, Peter B. [Copenhagen U.; Minakata, Hisakazu [Madrid, IFT

    2018-01-02

    We summarize our recent paper on neutrino oscillation probabilities in matter, explaining the importance, relevance and need for simple, highly accurate approximations to the neutrino oscillation probabilities in matter.

  13. Void probability scaling in hadron nucleus interactions

    International Nuclear Information System (INIS)

    Ghosh, Dipak; Deb, Argha; Bhattacharyya, Swarnapratim; Ghosh, Jayita; Bandyopadhyay, Prabhat; Das, Rupa; Mukherjee, Sima

    2002-01-01

    Heygi while investigating with the rapidity gap probability (that measures the chance of finding no particle in the pseudo-rapidity interval Δη) found that a scaling behavior in the rapidity gap probability has a close correspondence with the scaling of a void probability in galaxy correlation study. The main aim in this paper is to study the scaling behavior of the rapidity gap probability

  14. Pre-Service Teachers' Conceptions of Probability

    Science.gov (United States)

    Odafe, Victor U.

    2011-01-01

    Probability knowledge and skills are needed in science and in making daily decisions that are sometimes made under uncertain conditions. Hence, there is the need to ensure that the pre-service teachers of our children are well prepared to teach probability. Pre-service teachers' conceptions of probability are identified, and ways of helping them…

  15. Using Playing Cards to Differentiate Probability Interpretations

    Science.gov (United States)

    López Puga, Jorge

    2014-01-01

    The aprioristic (classical, naïve and symmetric) and frequentist interpretations of probability are commonly known. Bayesian or subjective interpretation of probability is receiving increasing attention. This paper describes an activity to help students differentiate between the three types of probability interpretations.

  16. Isolated Unilateral Pulmonary Artery Agenesis complicated by Symptomatic Aspergilloma

    LENUS (Irish Health Repository)

    Daly, A

    2017-11-01

    Isolated unilateral pulmonary artery agenesis is a rare diagnosis. Poor blood flow to the lung parenchyma renders the tissue susceptible to opportunistic infections. We present the unusual case of isolated unilateral pulmonary artery agenesis complicated by aspergilloma. Management options and considerations are discussed.

  17. Complications of pneumoconiosis: Radiologic overview

    International Nuclear Information System (INIS)

    Jun, Jae Sup; Jung, Jung Im; Kim, Hyo Rim; Ahn, Myeong Im; Han, Dae Hee; Ko, Jeong Min; Park, Seog Hee; Lee, Hae Giu; Arakawa, Hiroaki; Koo, Jung-Wan

    2013-01-01

    A wide spectrum of pulmonary complications occurs in patients with pneumoconiosis. Those complications include chronic obstructive pulmonary disease, hemoptysis, pneumothorax, pleural disease, tuberculosis, autoimmune disease, anthracofibrosis, chronic interstitial pneumonia, and malignancy. Generally, imaging workup starts with plain chest radiography. However, sometimes, plain radiography has limited role in the diagnosis of pulmonary complications of pneumoconiosis because of overlapping pneumoconiotic infiltration. Computed tomography (CT), ultrasonography (US), and magnetic resonance imaging (MRI) are potentially helpful for the detection of pulmonary complications in patients with pneumoconiosis. CT, with its excellent contrast resolution, is more sensitive and specific method than plain radiograph in the evaluation of pulmonary abnormalities. CT is useful in detecting lung parenchymal abnormalities caused by infection, anthracofibrosis, and chronic interstitial pneumonia. Also, CT is valuable in distinguishing localized pneumothorax from bullae and aiding the identification of multiloculated effusions. US can be used in detection of complicated pleural effusions and guidance of the thoracentesis procedure. MRI is useful for differentiating between progressive massive fibrosis and lung cancer. Radiologists need to be familiar with the radiologic and clinical manifestations of, as well as diagnostic approaches to, complications associated with pneumoconiosis. Knowledge of the various imaging features of pulmonary complications of pneumoconiosis can enhance early diagnosis and improve the chance to cure

  18. Complications of pneumoconiosis: Radiologic overview

    Energy Technology Data Exchange (ETDEWEB)

    Jun, Jae Sup [Department of Radiology, Seoul St. Mary' s Hospital, College of Medicine, The Catholic University of Korea (Korea, Republic of); Jung, Jung Im, E-mail: jijung@catholic.ac.kr [Department of Radiology, Seoul St. Mary' s Hospital, College of Medicine, The Catholic University of Korea (Korea, Republic of); Kim, Hyo Rim [Department of Radiology, Yeouido St. Mary' s Hospital, College of Medicine, The Catholic University of Korea (Korea, Republic of); Ahn, Myeong Im; Han, Dae Hee [Department of Radiology, Seoul St. Mary' s Hospital, College of Medicine, The Catholic University of Korea (Korea, Republic of); Ko, Jeong Min [Department of Radiology, St. Vincent Hospital, College of Medicine, The Catholic University of Korea (Korea, Republic of); Park, Seog Hee; Lee, Hae Giu [Department of Radiology, Seoul St. Mary' s Hospital, College of Medicine, The Catholic University of Korea (Korea, Republic of); Arakawa, Hiroaki [Department of Radiology, Dokkyo University School of Medicine (Japan); Koo, Jung-Wan [Department of Occupational and Environmental Medicine, Seoul St. Mary' s Hospital, The Catholic University of Korea (Korea, Republic of)

    2013-10-01

    A wide spectrum of pulmonary complications occurs in patients with pneumoconiosis. Those complications include chronic obstructive pulmonary disease, hemoptysis, pneumothorax, pleural disease, tuberculosis, autoimmune disease, anthracofibrosis, chronic interstitial pneumonia, and malignancy. Generally, imaging workup starts with plain chest radiography. However, sometimes, plain radiography has limited role in the diagnosis of pulmonary complications of pneumoconiosis because of overlapping pneumoconiotic infiltration. Computed tomography (CT), ultrasonography (US), and magnetic resonance imaging (MRI) are potentially helpful for the detection of pulmonary complications in patients with pneumoconiosis. CT, with its excellent contrast resolution, is more sensitive and specific method than plain radiograph in the evaluation of pulmonary abnormalities. CT is useful in detecting lung parenchymal abnormalities caused by infection, anthracofibrosis, and chronic interstitial pneumonia. Also, CT is valuable in distinguishing localized pneumothorax from bullae and aiding the identification of multiloculated effusions. US can be used in detection of complicated pleural effusions and guidance of the thoracentesis procedure. MRI is useful for differentiating between progressive massive fibrosis and lung cancer. Radiologists need to be familiar with the radiologic and clinical manifestations of, as well as diagnostic approaches to, complications associated with pneumoconiosis. Knowledge of the various imaging features of pulmonary complications of pneumoconiosis can enhance early diagnosis and improve the chance to cure.

  19. The extinction probability in systems randomly varying in time

    Directory of Open Access Journals (Sweden)

    Imre Pázsit

    2017-09-01

    Full Text Available The extinction probability of a branching process (a neutron chain in a multiplying medium is calculated for a system randomly varying in time. The evolution of the first two moments of such a process was calculated previously by the authors in a system randomly shifting between two states of different multiplication properties. The same model is used here for the investigation of the extinction probability. It is seen that the determination of the extinction probability is significantly more complicated than that of the moments, and it can only be achieved by pure numerical methods. The numerical results indicate that for systems fluctuating between two subcritical or two supercritical states, the extinction probability behaves as expected, but for systems fluctuating between a supercritical and a subcritical state, there is a crucial and unexpected deviation from the predicted behaviour. The results bear some significance not only for neutron chains in a multiplying medium, but also for the evolution of biological populations in a time-varying environment.

  20. Dependent Human Error Probability Assessment

    International Nuclear Information System (INIS)

    Simic, Z.; Mikulicic, V.; Vukovic, I.

    2006-01-01

    This paper presents an assessment of the dependence between dynamic operator actions modeled in a Nuclear Power Plant (NPP) PRA and estimate the associated impact on Core damage frequency (CDF). This assessment was done improve HEP dependencies implementation inside existing PRA. All of the dynamic operator actions modeled in the NPP PRA are included in this assessment. Determining the level of HEP dependence and the associated influence on CDF are the major steps of this assessment. A decision on how to apply the results, i.e., should permanent HEP model changes be made, is based on the resulting relative CDF increase. Some CDF increase was selected as a threshold based on the NPP base CDF value and acceptance guidelines from the Regulatory Guide 1.174. HEP dependence resulting in a CDF increase of > 5E-07 would be considered potential candidates for specific incorporation into the baseline model. The approach used to judge the level of dependence between operator actions is based on dependency level categories and conditional probabilities developed in the Handbook of Human Reliability Analysis with Emphasis on Nuclear Power Plant Applications NUREG/CR-1278. To simplify the process, NUREG/CR-1278 identifies five levels of dependence: ZD (zero dependence), LD (low dependence), MD (moderate dependence), HD (high dependence), and CD (complete dependence). NUREG/CR-1278 also identifies several qualitative factors that could be involved in determining the level of dependence. Based on the NUREG/CR-1278 information, Time, Function, and Spatial attributes were judged to be the most important considerations when determining the level of dependence between operator actions within an accident sequence. These attributes were used to develop qualitative criteria (rules) that were used to judge the level of dependence (CD, HD, MD, LD, ZD) between the operator actions. After the level of dependence between the various HEPs is judged, quantitative values associated with the

  1. PEG tubes: dealing with complications.

    Science.gov (United States)

    Malhi, Hardip; Thompson, Rosie

    A percutaneous endoscopic gastronomy tube can be used to deliver nutrition, hydration and medicines directly into the patient's stomach. Patients will require a tube if they are unable to swallow safely, putting them at risk of aspiration of food, drink and medicines into their lungs. It is vital that nurses are aware of the complications that may arise when caring for a patient with a PEG tube. It is equally important that nurses know how to deal with these complications or from where tc seek advice. This article provides a quick troubleshooting guide to help nurses deal with complications that can arise with PEG feeding.

  2. Pulmonary complications of cystic fibrosis

    International Nuclear Information System (INIS)

    Ng, M.Y.; Flight, W.; Smith, E.

    2014-01-01

    The life expectancy of patients with cystic fibrosis (CF) has steadily increased over recent decades with a corresponding increase in the frequency of complications of the disease. Radiologists are increasingly involved with managing and identifying the pulmonary complications of CF. This article reviews the common manifestations of CF lung disease as well as updating radiologists with a number of less well-known complications of the condition. Early and accurate detection of the pulmonary effects of CF are increasingly important to prevent irreversible lung damage and give patients the greatest possibility of benefiting from the new therapies becoming available, which correct the underlying defect causing CF

  3. Ocular complications of diabetes mellitus

    Institute of Scientific and Technical Information of China (English)

    Nihat Sayin; Necip Kara; Gokhan Pekel

    2015-01-01

    Diabetes mellitus (DM) is a important health problemthat induces ernestful complications and it causessignificant morbidity owing to specific microvascularcomplications such as, retinopathy, nephropathy andneuropathy, and macrovascular complications such as,ischaemic heart disease, and peripheral vasculopathy.It can affect children, young people and adults and isbecoming more common. Ocular complications associatedwith DM are progressive and rapidly becoming theworld's most significant cause of morbidity and arepreventable with early detection and timely treatment.This review provides an overview of five main ocularcomplications associated with DM, diabetic retinopathyand papillopathy, cataract, glaucoma, and ocular surfacediseases.

  4. Fundamentals of applied probability and random processes

    CERN Document Server

    Ibe, Oliver

    2014-01-01

    The long-awaited revision of Fundamentals of Applied Probability and Random Processes expands on the central components that made the first edition a classic. The title is based on the premise that engineers use probability as a modeling tool, and that probability can be applied to the solution of engineering problems. Engineers and students studying probability and random processes also need to analyze data, and thus need some knowledge of statistics. This book is designed to provide students with a thorough grounding in probability and stochastic processes, demonstrate their applicability t

  5. Probability of Failure in Random Vibration

    DEFF Research Database (Denmark)

    Nielsen, Søren R.K.; Sørensen, John Dalsgaard

    1988-01-01

    Close approximations to the first-passage probability of failure in random vibration can be obtained by integral equation methods. A simple relation exists between the first-passage probability density function and the distribution function for the time interval spent below a barrier before out......-crossing. An integral equation for the probability density function of the time interval is formulated, and adequate approximations for the kernel are suggested. The kernel approximation results in approximate solutions for the probability density function of the time interval and thus for the first-passage probability...

  6. An Objective Theory of Probability (Routledge Revivals)

    CERN Document Server

    Gillies, Donald

    2012-01-01

    This reissue of D. A. Gillies highly influential work, first published in 1973, is a philosophical theory of probability which seeks to develop von Mises' views on the subject. In agreement with von Mises, the author regards probability theory as a mathematical science like mechanics or electrodynamics, and probability as an objective, measurable concept like force, mass or charge. On the other hand, Dr Gillies rejects von Mises' definition of probability in terms of limiting frequency and claims that probability should be taken as a primitive or undefined term in accordance with modern axioma

  7. Paraconsistent Probabilities: Consistency, Contradictions and Bayes’ Theorem

    Directory of Open Access Journals (Sweden)

    Juliana Bueno-Soler

    2016-09-01

    Full Text Available This paper represents the first steps towards constructing a paraconsistent theory of probability based on the Logics of Formal Inconsistency (LFIs. We show that LFIs encode very naturally an extension of the notion of probability able to express sophisticated probabilistic reasoning under contradictions employing appropriate notions of conditional probability and paraconsistent updating, via a version of Bayes’ theorem for conditionalization. We argue that the dissimilarity between the notions of inconsistency and contradiction, one of the pillars of LFIs, plays a central role in our extended notion of probability. Some critical historical and conceptual points about probability theory are also reviewed.

  8. Tissue Classification

    DEFF Research Database (Denmark)

    Van Leemput, Koen; Puonti, Oula

    2015-01-01

    Computational methods for automatically segmenting magnetic resonance images of the brain have seen tremendous advances in recent years. So-called tissue classification techniques, aimed at extracting the three main brain tissue classes (white matter, gray matter, and cerebrospinal fluid), are now...... well established. In their simplest form, these methods classify voxels independently based on their intensity alone, although much more sophisticated models are typically used in practice. This article aims to give an overview of often-used computational techniques for brain tissue classification...

  9. Normal tissue tolerance to external beam radiation therapy: Peripheral nerves

    International Nuclear Information System (INIS)

    Henriques de Figueiredo, B.; Dejean, C.; Sargos, P.; Kantor, G.; Huchet, A.; Mamou, N.; Loiseau, H.

    2010-01-01

    Plexopathies and peripheral neuropathies appear progressively and with several years delay after radiotherapy. These lesions are observed principally after three clinical situations: supraclavicular and axillar irradiations for breast cancer, pelvic irradiations for various pathologies and limb irradiations for soft tissue sarcomas. Peripheral nerves and plexus (brachial and lumbosacral) are described as serial structures and are supposed to receive less than a given maximum dose linked to the occurrence of late injury. Literature data, mostly ancient, define the maximum tolerable dose to a threshold of 60 Gy and highlight also a great influence of fractionation and high fraction doses. For peripheral nerves, most frequent late effects are pain with significant differences of occurrence between 50 and 60 Gy. At last, associated pathologies (diabetes, vascular pathology, neuropathy) and associated treatments have probably to be taken into account as additional factors, which may increase the risk of these late radiation complications. (authors)

  10. A COMPLICATED GRIEF INTERVENTION MODEL

    African Journals Online (AJOL)

    2010-07-29

    Jul 29, 2010 ... of complicated grief as a contributing factor to impaired social functioning. This can ... includes a diagnosis of bereavement-related major depression if symptoms ..... networking, Social Sciences Citation Index, Social Sciences.

  11. Medical complications of bulimia nervosa.

    Science.gov (United States)

    Mehler, Philip S; O'Melia, Anne; Brown, Carrie; Gibson, Dennis; Hollis, Jeff; Westmoreland, Patricia

    2017-12-02

    Bulimia nervosa is a psychiatric disorder with many different medical sequelae. This article reviews the principal medical complications associated with bulimia nervosa, and emphasizes the importance of a timely approach to diagnosis and management.

  12. A very complicated pleural effusion

    Directory of Open Access Journals (Sweden)

    J.P. Gilbert*

    2013-12-01

    Discussion: Re-expansion pulmonary oedema is a recognised complication of large pleural effusion drainage. The mechanism remains unclear, although reduced left ventricular function, in this case from a possible pericardial effusion, may be a precipitant. To prevent this phenomenon the British Thoracic Society recommends draining a maximum of 1.5 litres of fluid. This case was further complicated by a pneumothorax; again a recognised complication, especially if there is underlying poor compliance of the lung parenchyma. Re-expansion pulmonary oedema has an incidence of <1% and pneumothorax <5%. Their occurrence has not previously been reported simultaneously. Large pleural effusions are commonly encountered in clinical practice in South Africa. The existence of multiple co-morbidities including tuberculosis, HIV and impaired cardiac function may complicate their management. This case highlights the need for close monitoring and controlled drainage of pleural effusions in emergency practice.

  13. A COMPLICATED GRIEF INTERVENTION MODEL

    African Journals Online (AJOL)

    2010-07-29

    Jul 29, 2010 ... work approach to therapy) in an attempt to develop a model for complicated grief intervention ..... way feels right for them, thus making them equal partners with .... This question points out the benefits of success and affords the.

  14. Liver Transplant: Complications/Medications

    Science.gov (United States)

    ... Transplant: Complications/Medications Viral Hepatitis Menu Menu Viral Hepatitis Viral Hepatitis Home For Veterans and the Public Veterans and the Public Home Hepatitis A Hepatitis B Hepatitis C Hepatitis C Home Getting ...

  15. Unusual Complications of Quinalphos Poisoning

    Directory of Open Access Journals (Sweden)

    Stalin Viswanathan

    2013-01-01

    Full Text Available This 40-year-old man was treated for suicidal quinalphos 25%EC consumption. He developed intermediate syndrome with normal response to repetitive nerve stimulation, pancreatitis with high enzyme elevations, and normal computed tomography and excreted black, brown, and orange urine sequentially over the first nine days of hospitalization. The last complication has not been previously reported with any organophosphate compound. He finally succumbed to complication of ventilator associated pneumonia related septic shock and ventricular tachycardia.

  16. Metabolic disorders in adipocytokine imbalance and gestational complications

    Directory of Open Access Journals (Sweden)

    Natalya B. Chabanova

    2017-06-01

    Full Text Available Adipose tissue as an endocrine organ synthesizes a large number of biologically active substances, adipocytokines, which have both local and systemic effects influencing the vascular wall, tissue sensitivity to insulin, glucose metabolism, and systemic inflammation. The data obtained from clinical and experimental studies demonstrate the close relationship between the imbalance of adipocytokines and pregnancy complications such as insulin resistance, gestational diabetes, and preeclampsia. In this connection, close attention of obstetrician-gynecologists and endocrinologists is focused on etiopathogenic aspects of the formation of gestational complications with metabolic disorders caused by an imbalance of adipocytokines with maternal obesity and to the search for markers of these disorders. The review presents the current literature data on adipose tissue hormones and their influence on the course of a gestational process.

  17. Palatal Perforation: A Rare Complication of Postanesthetic Necrosis

    Science.gov (United States)

    Gargi, Vidisha; Mohan, Ravi Prakash Sasankoti; Kamarthi, Nagaraju; Gupta, Swati

    2017-01-01

    The everyday practice of dentistry relies heavily on achieving adequate local anesthesia. Even though the safety record of local anesthetic agents is high, complications do occur. Palate is a favorable site for soft-tissue lesions. Various factors such as direct effects of the drug, blanching of the tissues during injection, relatively poor blood supply, and reactivation of the latent forms of herpes can all promote to tissue ischemia and a lesion in the palate. Among various complications, anesthetic necrotic ulcer is a rare and uncommon condition occurring mostly in the hard palate possibly after a local anesthetic infiltration. The ulceration is often deep and shows spontaneous but delayed healing. If proper treatment is not instituted on time, the necrosis can reach deep into the bone causing sequestrum formation and ultimately leading to palatal perforation. Here, we report a case of palatal perforation in a male patient followed by surgical interventions and follow-up. PMID:29042744

  18. Surgical anatomy of the retroperitoneal spaces, Part V: Surgical applications and complications.

    Science.gov (United States)

    Mirilas, Petros; Skandalakis, John E

    2010-04-01

    Knowledge of the surgical anatomy of the retroperitoneum is crucial for surgery of the retroperitoneal organs. Surgery is essential for treatment of retroperitoneal pathologies. The list of these diseases is extensive and comprises acute and chronic inflammatory processes (abscess, injury, hematoma, idiopathic fibrosis), metastatic neoplasms, and primary neoplasms from fibroadipose tissue, connective tissue, smooth and striated muscle, vascular tissue, somatic and sympathetic nervous tissue, extraadrenal chromaffin tissue, and lymphatic tissue. The retroperitoneum can be approached and explored by several routes, including the transperitoneal route and the extraperitoneal route. The retroperitoneal approach to the iliac fossa is used for ectopic renal transplantation. Safe and reliable primary retroperitoneal access can be performed for laparoscopic exploration. The anatomic complications of retroperitoneal surgery are the complications of the organs located in several compartments of the retroperitoneal space. Complications may arise from incisions to the somatic wall, somatic nerves, blood and lymphatic vessels, lymph nodes, visceral autonomous plexuses, and neighboring splanchna.

  19. Probability mapping of scarred myocardium using texture and intensity features in CMR images

    Science.gov (United States)

    2013-01-01

    Background The myocardium exhibits heterogeneous nature due to scarring after Myocardial Infarction (MI). In Cardiac Magnetic Resonance (CMR) imaging, Late Gadolinium (LG) contrast agent enhances the intensity of scarred area in the myocardium. Methods In this paper, we propose a probability mapping technique using Texture and Intensity features to describe heterogeneous nature of the scarred myocardium in Cardiac Magnetic Resonance (CMR) images after Myocardial Infarction (MI). Scarred tissue and non-scarred tissue are represented with high and low probabilities, respectively. Intermediate values possibly indicate areas where the scarred and healthy tissues are interwoven. The probability map of scarred myocardium is calculated by using a probability function based on Bayes rule. Any set of features can be used in the probability function. Results In the present study, we demonstrate the use of two different types of features. One is based on the mean intensity of pixel and the other on underlying texture information of the scarred and non-scarred myocardium. Examples of probability maps computed using the mean intensity of pixel and the underlying texture information are presented. We hypothesize that the probability mapping of myocardium offers alternate visualization, possibly showing the details with physiological significance difficult to detect visually in the original CMR image. Conclusion The probability mapping obtained from the two features provides a way to define different cardiac segments which offer a way to identify areas in the myocardium of diagnostic importance (like core and border areas in scarred myocardium). PMID:24053280

  20. JAW CYSTS AND GUIDED BONE REGENERATION (a late complication after enucleation

    Directory of Open Access Journals (Sweden)

    Hristina Lalabonova

    2013-10-01

    Full Text Available Maxillary jaw bone possesses a high regenerative capacity. Yet sometimes the defects enucleation of jaw cysts leaves may regenerate only partially or not at all. For this reason some researchers advise treatment of the residual cavities after cystectomy using bone regeneration stimulation methods. We report a case of an atypical complication after enucleation of a maxillary cyst manifesting itself eight years after the initial treatment. The symptoms the patient reported were at first periodic sweating on the left sides of face and head. This was followed by a piercing pain in the left palpebral fissure radiating to the middle of the palate and felt in the left cheekbone, left eye and left supraorbital ridge. The patient has a history of maxillary cysts recurring three times and of three operations she had 20, 12 and 8 years previously. The multiple recurrences of the cysts after their enucleation indicates poor regenerative capacity of the body which resulted in the formation of cicatricial tissue. It is most probably this tissue that was responsible for the disruption of the nerve conduction capacity which can account for the reported symptoms. We filled the cavity with bone graft material which boosted the bone structure regeneration. Although maxillary jaws possess high regenerative capacity we advise the use of guided bone regeneration in cases of large bone defects that usually occur after enucleation of jaw cysts.

  1. Probability concepts in quality risk management.

    Science.gov (United States)

    Claycamp, H Gregg

    2012-01-01

    Essentially any concept of risk is built on fundamental concepts of chance, likelihood, or probability. Although risk is generally a probability of loss of something of value, given that a risk-generating event will occur or has occurred, it is ironic that the quality risk management literature and guidelines on quality risk management tools are relatively silent on the meaning and uses of "probability." The probability concept is typically applied by risk managers as a combination of frequency-based calculation and a "degree of belief" meaning of probability. Probability as a concept that is crucial for understanding and managing risk is discussed through examples from the most general, scenario-defining and ranking tools that use probability implicitly to more specific probabilistic tools in risk management. A rich history of probability in risk management applied to other fields suggests that high-quality risk management decisions benefit from the implementation of more thoughtful probability concepts in both risk modeling and risk management. Essentially any concept of risk is built on fundamental concepts of chance, likelihood, or probability. Although "risk" generally describes a probability of loss of something of value, given that a risk-generating event will occur or has occurred, it is ironic that the quality risk management literature and guidelines on quality risk management methodologies and respective tools focus on managing severity but are relatively silent on the in-depth meaning and uses of "probability." Pharmaceutical manufacturers are expanding their use of quality risk management to identify and manage risks to the patient that might occur in phases of the pharmaceutical life cycle from drug development to manufacture, marketing to product discontinuation. A probability concept is typically applied by risk managers as a combination of data-based measures of probability and a subjective "degree of belief" meaning of probability. Probability as

  2. Intraoperative and Early Postoperative Complications of Manual Sutureless Cataract Extraction

    International Nuclear Information System (INIS)

    Iqbal, Y.; Zia, S.; Mirza, A. B.

    2014-01-01

    Objective: To determine the intraoperative and early postoperative complications of manual sutureless cataract extraction. Study Design: Case series. Place and Duration of Study: Redo Eye Hospital, Rawalpindi, Pakistan, from January 2009 to December 2010. Methodology: Three hundred patients of cataract through purposive non-probability sampling were selected. The patients underwent manual sutureless cataract surgery (MSCS) by single experienced surgeon and intraoperative complications were documented. The surgical technique was modified to deal with any intraoperative complications accordingly. Patients were examined on the first postoperative day and on the first postoperative week for any postoperative complications. The data was entered in Statistical Package for Social Sciences (SPSS) version 13.0 and the results were calculated in frequencies. Results: Among the 300 cases, 81.3% surgeries went uneventful whereas 18.6% had some complication. The common intraoperative complications were superior button-hole formation in 5%; posterior capsular rent in 5% and premature entry with iris prolapse in 3% cases. Postoperatively, the commonly encountered complications were striate keratopathy in 9.6% and hyphema 9%. At first week follow-up, 4% had striate keratopathy and 0.6% had hyphema. Striate keratopathy resolved with topical medication on subsequent follow-up. A total of 9 cases (3%) underwent second surgery: 2 cases for lens matter wash, 2 cases for hyphema and 5 cases needed suturing of wound for shallow anterior chamber due to wound leak. Conclusion: Superior button-hole formation, posterior capsular rent and premature entry were the common intraoperative complications of MSCS whereas the common early postoperative complications were striate keratopathy and hyphema. (author)

  3. Transition probability spaces in loop quantum gravity

    Science.gov (United States)

    Guo, Xiao-Kan

    2018-03-01

    We study the (generalized) transition probability spaces, in the sense of Mielnik and Cantoni, for spacetime quantum states in loop quantum gravity. First, we show that loop quantum gravity admits the structures of transition probability spaces. This is exemplified by first checking such structures in covariant quantum mechanics and then identifying the transition probability spaces in spin foam models via a simplified version of general boundary formulation. The transition probability space thus defined gives a simple way to reconstruct the discrete analog of the Hilbert space of the canonical theory and the relevant quantum logical structures. Second, we show that the transition probability space and in particular the spin foam model are 2-categories. Then we discuss how to realize in spin foam models two proposals by Crane about the mathematical structures of quantum gravity, namely, the quantum topos and causal sites. We conclude that transition probability spaces provide us with an alternative framework to understand various foundational questions of loop quantum gravity.

  4. Towards a Categorical Account of Conditional Probability

    Directory of Open Access Journals (Sweden)

    Robert Furber

    2015-11-01

    Full Text Available This paper presents a categorical account of conditional probability, covering both the classical and the quantum case. Classical conditional probabilities are expressed as a certain "triangle-fill-in" condition, connecting marginal and joint probabilities, in the Kleisli category of the distribution monad. The conditional probabilities are induced by a map together with a predicate (the condition. The latter is a predicate in the logic of effect modules on this Kleisli category. This same approach can be transferred to the category of C*-algebras (with positive unital maps, whose predicate logic is also expressed in terms of effect modules. Conditional probabilities can again be expressed via a triangle-fill-in property. In the literature, there are several proposals for what quantum conditional probability should be, and also there are extra difficulties not present in the classical case. At this stage, we only describe quantum systems with classical parametrization.

  5. UT Biomedical Informatics Lab (BMIL) probability wheel

    Science.gov (United States)

    Huang, Sheng-Cheng; Lee, Sara; Wang, Allen; Cantor, Scott B.; Sun, Clement; Fan, Kaili; Reece, Gregory P.; Kim, Min Soon; Markey, Mia K.

    A probability wheel app is intended to facilitate communication between two people, an "investigator" and a "participant", about uncertainties inherent in decision-making. Traditionally, a probability wheel is a mechanical prop with two colored slices. A user adjusts the sizes of the slices to indicate the relative value of the probabilities assigned to them. A probability wheel can improve the adjustment process and attenuate the effect of anchoring bias when it is used to estimate or communicate probabilities of outcomes. The goal of this work was to develop a mobile application of the probability wheel that is portable, easily available, and more versatile. We provide a motivating example from medical decision-making, but the tool is widely applicable for researchers in the decision sciences.

  6. A probability space for quantum models

    Science.gov (United States)

    Lemmens, L. F.

    2017-06-01

    A probability space contains a set of outcomes, a collection of events formed by subsets of the set of outcomes and probabilities defined for all events. A reformulation in terms of propositions allows to use the maximum entropy method to assign the probabilities taking some constraints into account. The construction of a probability space for quantum models is determined by the choice of propositions, choosing the constraints and making the probability assignment by the maximum entropy method. This approach shows, how typical quantum distributions such as Maxwell-Boltzmann, Fermi-Dirac and Bose-Einstein are partly related with well-known classical distributions. The relation between the conditional probability density, given some averages as constraints and the appropriate ensemble is elucidated.

  7. Fundamentals of applied probability and random processes

    CERN Document Server

    Ibe, Oliver

    2005-01-01

    This book is based on the premise that engineers use probability as a modeling tool, and that probability can be applied to the solution of engineering problems. Engineers and students studying probability and random processes also need to analyze data, and thus need some knowledge of statistics. This book is designed to provide students with a thorough grounding in probability and stochastic processes, demonstrate their applicability to real-world problems, and introduce the basics of statistics. The book''s clear writing style and homework problems make it ideal for the classroom or for self-study.* Good and solid introduction to probability theory and stochastic processes * Logically organized; writing is presented in a clear manner * Choice of topics is comprehensive within the area of probability * Ample homework problems are organized into chapter sections

  8. Striatal activity is modulated by target probability.

    Science.gov (United States)

    Hon, Nicholas

    2017-06-14

    Target probability has well-known neural effects. In the brain, target probability is known to affect frontal activity, with lower probability targets producing more prefrontal activation than those that occur with higher probability. Although the effect of target probability on cortical activity is well specified, its effect on subcortical structures such as the striatum is less well understood. Here, I examined this issue and found that the striatum was highly responsive to target probability. This is consistent with its hypothesized role in the gating of salient information into higher-order task representations. The current data are interpreted in light of that fact that different components of the striatum are sensitive to different types of task-relevant information.

  9. Defining Probability in Sex Offender Risk Assessment.

    Science.gov (United States)

    Elwood, Richard W

    2016-12-01

    There is ongoing debate and confusion over using actuarial scales to predict individuals' risk of sexual recidivism. Much of the debate comes from not distinguishing Frequentist from Bayesian definitions of probability. Much of the confusion comes from applying Frequentist probability to individuals' risk. By definition, only Bayesian probability can be applied to the single case. The Bayesian concept of probability resolves most of the confusion and much of the debate in sex offender risk assessment. Although Bayesian probability is well accepted in risk assessment generally, it has not been widely used to assess the risk of sex offenders. I review the two concepts of probability and show how the Bayesian view alone provides a coherent scheme to conceptualize individuals' risk of sexual recidivism.

  10. Spatial probability aids visual stimulus discrimination

    Directory of Open Access Journals (Sweden)

    Michael Druker

    2010-08-01

    Full Text Available We investigated whether the statistical predictability of a target's location would influence how quickly and accurately it was classified. Recent results have suggested that spatial probability can be a cue for the allocation of attention in visual search. One explanation for probability cuing is spatial repetition priming. In our two experiments we used probability distributions that were continuous across the display rather than relying on a few arbitrary screen locations. This produced fewer spatial repeats and allowed us to dissociate the effect of a high probability location from that of short-term spatial repetition. The task required participants to quickly judge the color of a single dot presented on a computer screen. In Experiment 1, targets were more probable in an off-center hotspot of high probability that gradually declined to a background rate. Targets garnered faster responses if they were near earlier target locations (priming and if they were near the high probability hotspot (probability cuing. In Experiment 2, target locations were chosen on three concentric circles around fixation. One circle contained 80% of targets. The value of this ring distribution is that it allowed for a spatially restricted high probability zone in which sequentially repeated trials were not likely to be physically close. Participant performance was sensitive to the high-probability circle in addition to the expected effects of eccentricity and the distance to recent targets. These two experiments suggest that inhomogeneities in spatial probability can be learned and used by participants on-line and without prompting as an aid for visual stimulus discrimination and that spatial repetition priming is not a sufficient explanation for this effect. Future models of attention should consider explicitly incorporating the probabilities of targets locations and features.

  11. Is probability of frequency too narrow?

    International Nuclear Information System (INIS)

    Martz, H.F.

    1993-01-01

    Modern methods of statistical data analysis, such as empirical and hierarchical Bayesian methods, should find increasing use in future Probabilistic Risk Assessment (PRA) applications. In addition, there will be a more formalized use of expert judgment in future PRAs. These methods require an extension of the probabilistic framework of PRA, in particular, the popular notion of probability of frequency, to consideration of frequency of frequency, frequency of probability, and probability of probability. The genesis, interpretation, and examples of these three extended notions are discussed

  12. Complications

    Science.gov (United States)

    ... Rights Employment Discrimination Health Care Professionals Law Enforcement Driver's License For Lawyers Food & Fitness Home Food MyFoodAdvisor ... Fit Types of Activity Weight Loss Assess Your Lifestyle Getting Started Food Choices In My Community Home ...

  13. Pulmonary complications in renal transplantation

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jung Bin; Choi, Yo Won; Jeon, Seok Chol; Park, Choong Ki; Lee, Seung Rho; Hahm, Chang Kok; Joo, Kyung Bin [Hanyang University College of Medicine, Seoul (Korea, Republic of)

    2003-04-01

    To evaluate the radiographic and CT findings of pulmonary complications other than pulmonary edema arising from renal transplantation. Among 393 patients who had undergone renal transplantation at our hospital during a previous ten-year period, 23 with pulmonary complications other than pulmonary edema were included in this study. The complications involved were infection caused by CMV (n=6), bacteria (n=4), fungus (n=4), tuberculosis (n=2), varicella (n=1) or chlamydia (n=1), and malignancy involving lung cancer (n=4) or Kaposi's sarcoma (n=1). Two chest radiologists reviewed all images. The complications manifesting mainly as pulmonary nodules were lung cancer (4/4), tuberculosis (1/2), and Kaposi's sarcoma (1/1). Pulmonary consolidation was a main feature in bacterial infection (4/4), fungal infection (3/4), tuberculosis (1/2), chlamydial infection (1/1), and varicellar pneumonia (1/1). Ground-glass attenuation was a main CT feature in CMV pneumonia (4/6), and increased interstitial making was a predominant radiographic feature in CMV pneumonia (2/6). The main radiologic features described above can be helpful for differential diagnosis of the pulmonary complications of renal transplantation.

  14. Can avoidance of complications lead to biased healthcare decisions?

    Directory of Open Access Journals (Sweden)

    Jennifer Amsterlaw

    2006-07-01

    : colostomy, chronic diarrhea, wound infection, or an %intermittent bowel obstruction. The complicated surgery dominates the %uncomplicated surgery as long as life with complications is preferred %over death. However, people's aversion to these %complications might make them choose the uncomplicated surgery, the %dominated alternative. %Methods: We presented the above scenario to a general population sample %recruited from the cafeteria of a university medical center. %Information about the probability of treatment outcomes was presented %both in text and in a summary table. Participants were then asked to %select which surgery they would choose. We varied the presentation %format in a series of follow-up surveys to examine effects on choice. %Results: In our first survey, 51\\% of the sample (N=87, M age= 39 yrs., %65\\% female selected the dominated alternative, the uncomplicated %surgery. Participants justified this choice by saying that the death %risks for the two surgeries were essentially the same, and the %uncomplicated surgery avoided the risk of complications. In the %follow-up surveys, preference for the uncomplicated surgery remained %relatively consistent (39\\%--51\\% despite (a presenting the risks in %frequencies rather than percents, (b grouping the 4 complications into %a single category, or (c giving the uncomplicated surgery a small %chance of complications as well. Even when a pre-decision %``focusing exercise'' required people to %state directly their preferences between life with each complication %versus death (92\\% preferred life with any of the complications listed %over death, 49\\% of participants (N=77, M age= 39 yrs., 67\\% female %still chose the uncomplicated surgery. %Conclusions: People's fear of complications leads them %to ignore important differences between treatments. This tendency %appears remarkably resistant to debiasing approaches and likely leads %patients to make healthcare decisions that are inconsistent with their %own

  15. Skin autofluorescence : A tool to identify type 2 diabetic patients at risk for developing microvascular complications

    NARCIS (Netherlands)

    Gerrits, E.sther G.; Lutgers, Helen L.; Kleefstra, Nanne; Graaff, R.; Groenier, Klaas H.; Smit, Andries J.; Gans, Reinold; Bilo, Henk J.

    OBJECTIVE - Skin auto fluorescence is a noninvasive measure of the level of tissue accumulation of advanced glycation end products, representing cumulative glycemic and oxidative stress. Recent studies have already shown a relationship between skin autofluorescence and diabetes complications, as

  16. Ingestion of caustic substances and its complications

    Directory of Open Access Journals (Sweden)

    Rui Celso Martins Mamede

    2001-01-01

    Full Text Available CONTEXT: Caustic substances cause tissue destruction through liquefaction or coagulation reactions and the intensity of destruction depends on the type, concentration, time of contact and amount of the substance ingested. OBJECTIVES: To analyze the complications in patients who ingested caustic substances and correlate them with the amount of caustic soda ingested. DESIGN: Retrospective study. SETTING: University hospital, a referral center. PARTICIPANTS: A total of 239 patients who ingested caustic soda. MAIN MEASUREMENTS: The amount of granulated caustic substance ingested was measured as tablespoonfuls and the following complications were analyzed: esophagitis, esophageal stenosis and progression to cancer, fistulas, perforations, stomach lesions, brain abscesses, and death. Stenosis was classified as mild, moderate or severe according to the radiological findings. RESULTS: We observed an 89.3% incidence of esophagitis; 72.6% of the cases involved progression to stenosis and 1% died during the acute phase. Stenosis was mild in 17.6% of cases, moderate in 59.3% and severe in 23%. The incidence of stenosis was 80.8% in women and 62.5% in men. The incidence of stenosis was 46.9% in the group that ingested "fragments" and 93.6% in the group that ingested one or more tablespoonfuls of caustic substances. Among subjects who ingested one or more tablespoonfuls, 32.2% developed lesions of the stomach-duodenum, whereas the ingestion of "fragments" was not sufficient to induce these lesions. There was no correlation between the intensity of lesions of the esophagus and of the stomach. Progression to cancer of the esophagus occurred in 1.8% of cases, death during the chronic phase in 1.4%, perforations in 4.6%, fistulas in 0.9%, and brain abscesses in 1.4%. CONCLUSIONS: The complications were related to the amount of caustic soda ingested. Small amounts caused esophagitis or stenosis and large amounts increased the risk of fistulas, perforations and

  17. Metabolomics window into diabetic complications.

    Science.gov (United States)

    Wu, Tao; Qiao, Shuxuan; Shi, Chenze; Wang, Shuya; Ji, Guang

    2018-03-01

    Diabetes has become a major global health problem. The elucidation of characteristic metabolic alterations during the diabetic progression is critical for better understanding its pathogenesis, and identifying potential biomarkers and drug targets. Metabolomics is a promising tool to reveal the metabolic changes and the underlying mechanism involved in the pathogenesis of diabetic complications. The present review provides an update on the application of metabolomics in diabetic complications, including diabetic coronary artery disease, diabetic nephropathy, diabetic retinopathy and diabetic neuropathy, and this review provides notes on the prevention and prediction of diabetic complications. © 2017 The Authors. Journal of Diabetes Investigation published by Asian Association for the Study of Diabetes (AASD) and John Wiley & Sons Australia, Ltd.

  18. Avoiding Complications with MPFL Reconstruction.

    Science.gov (United States)

    Smith, Marvin K; Werner, Brian C; Diduch, David R

    2018-05-12

    To discuss the potentially significant complications associated with medial patellofemoral ligament (MPFL) reconstruction. Additionally, to review the most current and relevant literature with an emphasis on avoiding these potential complications. Multiple cadaveric studies have characterized the anatomy of the MPFL and the related morphologic abnormalities that contribute to recurrent lateral patellar instability. Such abnormalities include patella alta, excessive tibial tubercle to trochlear grove (TT-TG) distance, trochlear dysplasia, and malalignment. Recent studies have evaluated the clinical outcomes associated with the treatment of concomitant pathology in combination with MPFL reconstruction, which is critical in avoiding recurrent instability and complications. Although there remains a lack of consensus regarding various critical aspects of MPFL reconstruction, certain concepts remain imperative. Our preferred methods and rationales for surgical techniques are described. These include appropriate work up, a combination of procedures to address abnormal morphology, anatomical femoral insertion, safe and secure patellar fixation, appropriate graft length fixation, and thoughtful knee flexion during fixation.

  19. Neurological complications following bariatric surgery

    Directory of Open Access Journals (Sweden)

    Yara Dadalti Fragoso

    2012-09-01

    Full Text Available OBJECTIVE: It was to report on Brazilian cases of neurological complications from bariatric surgery. The literature on the subject is scarce. METHOD: Cases attended by neurologists in eight different Brazilian cities were collected and described in the present study. RESULTS: Twenty-six cases were collected in this study. Axonal polyneuropathy was the most frequent neurological complication, but cases of central demyelination, Wernicke syndrome, optical neuritis, radiculits, meralgia paresthetica and compressive neuropathies were also identified. Twenty-one patients (80% had partial or no recovery from the neurological signs and symptoms. CONCLUSION: Bariatric surgery, a procedure that is continuously increasing in popularity, is not free of potential neurological complications that should be clearly presented to the individual undergoing this type of surgery. Although a clear cause-effect relation cannot be established for the present cases, the cumulative literature on the subject makes it important to warn the patient of the potential risks of this procedure.

  20. Neurological complications of infective endocarditis

    International Nuclear Information System (INIS)

    Khan, Sonia A.A.; Yaqub, Basim A.; Al-Deeb, Saleh M.

    1996-01-01

    We reviewed the files of 80 successive patients with native and prosthetic valve endocarditis admitted to Riyadh Armed Forces Hospital. Neurolological complications (NC) occurred in 28 (35%) patients. The valves involved were mitral in 12 (43%), aortic in eight (29%), combined mitral and aortic lesions in six (21%) and others in two (7%). The common causative organisms were Streptococci in 12 (43%), Staphylococcus aureus and Staphylococcus epidermides, both occurring in four (14%). Compared to the 52 infective endocarditis patients with no neurological complications (NNC), the NC occurred more frequently in male patients, those with aortic valve lesion, those with atrial fibrillation, those with delayed therapy and those with causative organisms being Streptococci or Staphylococci. Eleven patients died (39%), 12 (43%) recovered with motor sequelae, six (21%) had seizure disorder and five (18%) had full recovery. The frequency of neurological complications and mortality is comparable to those reported in the literature: however, the frequency was higher in our patients. (author)

  1. Venous thromboembolism and arterial complications.

    Science.gov (United States)

    Prandoni, Paolo; Piovella, Chiara; Pesavento, Raffaele

    2012-04-01

    An increasing body of evidence suggests the likelihood of a link between venous and arterial thrombosis. The two vascular complications share several risk factors, such as age, obesity, smoking, diabetes mellitus, blood hypertension, hypertriglyceridemia, and metabolic syndrome. Moreover, there are many examples of conditions accounting for both venous and arterial thrombosis, such as the antiphospholipid antibody syndrome, hyperhomocysteinemia, malignancies, infections, and the use of hormonal treatment. Finally, several recent studies have consistently shown that patients with venous thromboembolism are at a higher risk of arterial thrombotic complications than matched control individuals. We, therefore, speculate the two vascular complications are simultaneously triggered by biological stimuli responsible for activating coagulation and inflammatory pathways in both the arterial and the venous system. Future studies are needed to clarify the nature of this association, to assess its extent, and to evaluate its implications for clinical practice. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  2. The method of modular characteristic direction probabilities in MPACT

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Z. [School of Nuclear Science and Technology, Xi' an Jiaotong University, No. 28 Xianning west road, Xi' an, Shaanxi 710049 (China); Kochunas, B.; Collins, B.; Downar, T. [Department of Nuclear Engineering and Radiological Sciences, University of Michigan, 2200 Bonisteel, Ann Arbor, MI 48109 (United States); Wu, H. [School of Nuclear Science and Technology, Xi' an Jiaotong University, No. 28 Xianning west road, Xi' an, Shaanxi 710049 (China)

    2013-07-01

    The method of characteristic direction probabilities (CDP) is based on a modular ray tracing technique which combines the benefits of the collision probability method (CPM) and the method of characteristics (MOC). This past year CDP was implemented in the transport code MPACT for 2-D and 3-D transport calculations. By only coupling the fine mesh regions passed by the characteristic rays in the particular direction, the scale of the probabilities matrix is much smaller compared to the CPM. At the same time, the CDP has the same capacity of dealing with the complicated geometries with the MOC, because the same modular ray tracing techniques are used. Results from the C5G7 benchmark problems are given for different cases to show the accuracy and efficiency of the CDP compared to MOC. For the cases examined, the CDP and MOC methods were seen to differ in k{sub eff} by about 1-20 pcm, and the computational efficiency of the CDP appears to be better than the MOC for some problems. However, in other problems, particularly when the CDP matrices have to be recomputed from changing cross sections, the CDP does not perform as well. This indicates an area of future work. (authors)

  3. Stem cell research: licit or complicit? Is a medical breakthrough based on embryonic and fetal tissue compatible with Catholic teaching?

    Science.gov (United States)

    Branick, V; Lysaught, M T

    1999-01-01

    In November 1998 biologists announced that they had discovered a way to isolate and preserve human stem cells. Since stem cells are capable of developing into any kind of human tissue or organ, this was a great scientific coup. Researchers envision using the cells to replace damaged organs and to restore tissue destroyed by, for example, Parkinson's disease, diabetes, or even Alzheimer's. But, since stem cells are taken from aborted embryonic and fetal tissue or "leftover" in vitro embryos, their use raises large ethical issues. The National Institutes of Health (NIH) recently decided to fund research employing, not stem cells, but "cell lines" derived from them. The NIH has essentially made an ethical determination, finding sufficient "distance" between cell lines and abortion. Can Catholic universities sponsoring biological research agree with this finding? Probably not. In Catholic teaching, the concept of "complicity" would likely preclude such research. However, Catholic teaching would probably allow research done with stem cells obtained from postpartum placental tissue and from adult bone marrow and tissue. These cells, which lack the pluripotency of embryonic and fetal stem cells, are nevertheless scientifically promising and do not involve the destruction of human life.

  4. Complications After Cosmetic Surgery Tourism.

    Science.gov (United States)

    Klein, Holger J; Simic, Dario; Fuchs, Nina; Schweizer, Riccardo; Mehra, Tarun; Giovanoli, Pietro; Plock, Jan A

    2017-04-01

    Cosmetic surgery tourism characterizes a phenomenon of people traveling abroad for aesthetic surgery treatment. Problems arise when patients return with complications or need of follow-up care. To investigate the complications of cosmetic surgery tourism treated at our hospital as well as to analyze arising costs for the health system. Between 2010 and 2014, we retrospectively included all patients presenting with complications arising from cosmetic surgery abroad. We reviewed medical records for patients' characteristics including performed operations, complications, and treatment. Associated cost expenditure and Diagnose Related Groups (DRG)-related reimbursement were analyzed. In total 109 patients were identified. All patients were female with a mean age of 38.5 ± 11.3 years. Most procedures were performed in South America (43%) and Southeast (29.4%) or central Europe (24.8%), respectively. Favored procedures were breast augmentation (39.4%), abdominoplasty (11%), and breast reduction (7.3%). Median time between the initial procedure abroad and presentation was 15 days (interquartile range [IQR], 9) for early, 81.5 days (IQR, 69.5) for midterm, and 4.9 years (IQR, 9.4) for late complications. Main complications were infections (25.7%), wound breakdown (19.3%), and pain/discomfort (14.7%). The majority of patients (63.3%) were treated conservatively; 34.8% became inpatients with a mean hospital stay of 5.2 ± 3.8 days. Overall DRG-related reimbursement premiums approximately covered the total costs. Despite warnings regarding associated risks, cosmetic surgery tourism has become increasingly popular. Efficient patients' referral to secondary/tertiary care centers with standardized evaluation and treatment can limit arising costs without imposing a too large burden on the social healthcare system. 4. © 2016 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com

  5. Intracraneal complications after raquis surgery.

    Science.gov (United States)

    Sierra, J J; Malillos, M

    Intracraneal bleeding is a rare complication after raquis surgery. It is believed to occur as a drop in the intracraneal pressure after a loss of CSF secondary to an iatrogenic dural tear. We report a patient who after surgery for lumbar stenosis presented a subarachnoid haemorrhage, an intraparenchymal haematoma, and a subdural haematoma. To our knowledge, this is the first report in the literature with such complications after this type of surgery. Copyright © 2017 SECOT. Publicado por Elsevier España, S.L.U. All rights reserved.

  6. LVAD pannus complicating destination therapy

    Directory of Open Access Journals (Sweden)

    Maya Ignaszewski

    2017-11-01

    Full Text Available Despite advances in technology, ventricular assist devices still experience a number of complications limiting their long-term use. We present a 73-year-old woman implanted with a left ventricular assist device (LVAD five years prior due to end-stage dilated cardiomyopathy, who died several weeks after admission to the hospital. Post-mortem examination revealed a large obstructing pannus in the LVAD inflow. As a result of increased LVAD use, complications such as infection, device thrombosis and pannus must be promptly recognized and managed appropriately to ensure the greatest chance of patient survival.

  7. Sigmoid Volvulus Complicating Postpartum Period

    Directory of Open Access Journals (Sweden)

    Kelsey E. Ward

    2017-01-01

    Full Text Available Background. Sigmoid volvulus is a rare complication of pregnancy and the puerperium. Case. A 19-year-old patient, gravida 1 para 0 at 41 0/7 weeks of gestation, admitted for late-term induction of labor underwent an uncomplicated primary low transverse cesarean delivery for arrest of descent. Her postoperative period was complicated by sudden onset of abdominal pain and the ultimate diagnosis of sigmoid volvulus. Conclusion. Prompt surgical evaluation of an acute abdomen in the postpartum period is essential; delayed diagnosis and treatment can lead to significant maternal morbidity and mortality.

  8. Probability of Grounding and Collision Events

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup

    1996-01-01

    To quantify the risks involved in ship traffic, rational criteria for collision and grounding accidents are developed. This implies that probabilities as well as inherent consequences can be analysed and assessed. The presnt paper outlines a method for evaluation of the probability of ship...

  9. Probability of Grounding and Collision Events

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup

    1996-01-01

    To quantify the risks involved in ship traffic, rational criteria for collision and grounding accidents have to be developed. This implies that probabilities as well as inherent consequences have to be analyzed and assessed.The present notes outline a method for evaluation of the probability...

  10. Introducing Disjoint and Independent Events in Probability.

    Science.gov (United States)

    Kelly, I. W.; Zwiers, F. W.

    Two central concepts in probability theory are those of independence and mutually exclusive events. This document is intended to provide suggestions to teachers that can be used to equip students with an intuitive, comprehensive understanding of these basic concepts in probability. The first section of the paper delineates mutually exclusive and…

  11. Selected papers on probability and statistics

    CERN Document Server

    2009-01-01

    This volume contains translations of papers that originally appeared in the Japanese journal Sūgaku. The papers range over a variety of topics in probability theory, statistics, and applications. This volume is suitable for graduate students and research mathematicians interested in probability and statistics.

  12. Collective probabilities algorithm for surface hopping calculations

    International Nuclear Information System (INIS)

    Bastida, Adolfo; Cruz, Carlos; Zuniga, Jose; Requena, Alberto

    2003-01-01

    General equations that transition probabilities of the hopping algorithms in surface hopping calculations must obey to assure the equality between the average quantum and classical populations are derived. These equations are solved for two particular cases. In the first it is assumed that probabilities are the same for all trajectories and that the number of hops is kept to a minimum. These assumptions specify the collective probabilities (CP) algorithm, for which the transition probabilities depend on the average populations for all trajectories. In the second case, the probabilities for each trajectory are supposed to be completely independent of the results from the other trajectories. There is, then, a unique solution of the general equations assuring that the transition probabilities are equal to the quantum population of the target state, which is referred to as the independent probabilities (IP) algorithm. The fewest switches (FS) algorithm developed by Tully is accordingly understood as an approximate hopping algorithm which takes elements from the accurate CP and IP solutions. A numerical test of all these hopping algorithms is carried out for a one-dimensional two-state problem with two avoiding crossings which shows the accuracy and computational efficiency of the collective probabilities algorithm proposed, the limitations of the FS algorithm and the similarity between the results offered by the IP algorithm and those obtained with the Ehrenfest method

  13. Examples of Neutrosophic Probability in Physics

    Directory of Open Access Journals (Sweden)

    Fu Yuhua

    2015-01-01

    Full Text Available This paper re-discusses the problems of the so-called “law of nonconservation of parity” and “accelerating expansion of the universe”, and presents the examples of determining Neutrosophic Probability of the experiment of Chien-Shiung Wu et al in 1957, and determining Neutrosophic Probability of accelerating expansion of the partial universe.

  14. Eliciting Subjective Probabilities with Binary Lotteries

    DEFF Research Database (Denmark)

    Harrison, Glenn W.; Martínez-Correa, Jimmy; Swarthout, J. Todd

    objective probabilities. Drawing a sample from the same subject population, we find evidence that the binary lottery procedure induces linear utility in a subjective probability elicitation task using the Quadratic Scoring Rule. We also show that the binary lottery procedure can induce direct revelation...

  15. Probability Issues in without Replacement Sampling

    Science.gov (United States)

    Joarder, A. H.; Al-Sabah, W. S.

    2007-01-01

    Sampling without replacement is an important aspect in teaching conditional probabilities in elementary statistics courses. Different methods proposed in different texts for calculating probabilities of events in this context are reviewed and their relative merits and limitations in applications are pinpointed. An alternative representation of…

  16. Some open problems in noncommutative probability

    International Nuclear Information System (INIS)

    Kruszynski, P.

    1981-01-01

    A generalization of probability measures to non-Boolean structures is discussed. The starting point of the theory is the Gleason theorem about the form of measures on closed subspaces of a Hilbert space. The problems are formulated in terms of probability on lattices of projections in arbitrary von Neumann algebras. (Auth.)

  17. Probability: A Matter of Life and Death

    Science.gov (United States)

    Hassani, Mehdi; Kippen, Rebecca; Mills, Terence

    2016-01-01

    Life tables are mathematical tables that document probabilities of dying and life expectancies at different ages in a society. Thus, the life table contains some essential features of the health of a population. Probability is often regarded as a difficult branch of mathematics. Life tables provide an interesting approach to introducing concepts…

  18. Teaching Probability: A Socio-Constructivist Perspective

    Science.gov (United States)

    Sharma, Sashi

    2015-01-01

    There is a considerable and rich literature on students' misconceptions in probability. However, less attention has been paid to the development of students' probabilistic thinking in the classroom. This paper offers a sequence, grounded in socio-constructivist perspective for teaching probability.

  19. Stimulus Probability Effects in Absolute Identification

    Science.gov (United States)

    Kent, Christopher; Lamberts, Koen

    2016-01-01

    This study investigated the effect of stimulus presentation probability on accuracy and response times in an absolute identification task. Three schedules of presentation were used to investigate the interaction between presentation probability and stimulus position within the set. Data from individual participants indicated strong effects of…

  20. 47 CFR 1.1623 - Probability calculation.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Probability calculation. 1.1623 Section 1.1623 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRACTICE AND PROCEDURE Random Selection Procedures for Mass Media Services General Procedures § 1.1623 Probability calculation. (a) All calculations shall be...