1,721,223 research outputs found
Treatment of idiopathic hemifacial spasm with radiosurgery or hypofractionated stereotactic radiotherapy: preliminary results.
No full textAbstract
INTRODUCTION: Microvascular decompression in the posterior cranial fossa is the first treatment option for hemifacial spasm. For patients not suitable for surgery because of advanced age, poor general conditions or patients who refuse surgery, radiotherapeutic treatment could be an alternative. Only one case of resolution of hemifacial spasm in a patient undergoing radiosurgery for an intracanalicular vestibular schwannoma has been described in the literature. In this article we present three patients affected by idiopathic hemifacial spasm, refractory to medical therapy and botulinum toxin injections, who were treated by radiosurgery in one case and hypofractionated stereotactic radiotherapy in the other two.
METHODS: Radiosurgery, with a single dose of 8 Gy, was used in the first patient affected by idiopathic hemifacial spasm and autoimmune polyneuropathy with severe hypoacusia; hypofractionated stereotactic radiotherapy, with 15 Gy in 5 fractions of 3 Gy each, was preferred in the other 2 cases. In all patients, the target consisted of the vestibulocochlear-facial bundle immediately before its entry into the internal acoustic foramen.
RESULTS: A marked improvement of symptoms was observed in 2 patients, and almost complete disappearance in the other case, with no complications, particularly, auditory.
CONCLUSION: The mean follow-up time of 24 months reported here could be judged too short, and our series too small, but the good results observed so far lead us to underline that, as in trigeminal neuralgia, radiosurgery or hypofractionated stereotactic radiotherapy could represent a therapeutic alternative to microvascular decompression for idiopathic hemifacial spasm for patients not suitable for surgery
Response to: comment on “Impact of tumor site on the prognosis of small bowel adenocarcinoma”
No full textTo test the validity of the model and answer the second question by Wang et al.,2 considering the small sample of the population, we implemented the analysis including the cross-validation with bootstrapping. To quantify the discrimination performance of the model, Harrell’s C-index was measured. The model was subjected to bootstrapping validation (1000 bootstrap resamples) to calculate the optimistic corrected estimate of C-index. The C-index for OS models was 0.70 while the corrected C-index was 0.67. Despite the small sample, the conclusions of our model seem to be robust. The potential for significant bias has already been mentioned in our report1 and the results must be considered cautiously. Large-scale studies are warranted
Astroparticle experiments to Improve the biological risk assessment of exposure to Ionizing radiation in the exploratory space missions:. The research topic initiative
No full textThe actual and next decade will be characterized by an exponential increase in the Beyond Low Earth Orbit space
exploration. In this context, a detailed space radiation field characterization will be crucial to optimize radioprotection
strategies, assess the risk of the health hazard related to human space exploration, and reduce the damages potentially
induced to astronauts from galactic cosmic radiation. Since the beginning of the century, many astroparticle experiments
investigating the unknown universe components (e.g., dark matter, antimatter, dark energy) have collected enormous
amounts of data regarding the cosmic ray (CR) components of the radiation in space. Such experiments are CR
observatories, and the collected CR events contain valuable information that can enhance the space radiation field
characterization. This paper will briefly present the status of the art of this research topic, and a research initiative
titled ”Astroparticle Experiments to Improve the Biological Risk Assessment of Exposure to Ionizing Radiation in the
Exploratory Space Missions” will be introduced
Calibration of an environmental monitoring system for a radiometabolic therapy ward using Lu-177
No full textRadiopharmaceuticals based on Lu-177 are finding increasing use in radiometabolic therapy. The ordinary practice requires radiation monitoring of the patient. To this end, detectors need to be calibrated in the geometry used and for the radioisotope used. This work presents an experimental investigation coupled with Monte Carlo calculations. This procedure yielded a calibration factor of practical use in everyday clinical practice
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Quantitative analysis of basal and interim PET/CT images for predicting tumor recurrence in patients with Hodgkin's lymphoma
No full textObjectivesThe qualitative analysis of interim PET has been reported to be useful for predicting the outcome of Hodgkin's lymphoma (HL) after chemotherapy. As the next step, our study aims to present a quantitative analysis on the basis of both a basal (PET/CT0) and an interim (PET/CT2) scan to improve the prognostic value of imaging in HL patients.Patients and methodsA cohort of 68 patients undergoing a basal and an interim scan with F-18-fluorodeoxyglucose after two cycles of chemotherapy consisting of adriamycin, bleomycin, vinblastine, and dacarbazine were examined. Two subsets of patients with a positive and a negative interim scan were selected.ResultsIn patients with a negative scan, a total of 108 lymph node lesions showing a good response to chemotherapy were contoured, whereas in the remaining patients with positive scans, six responder and 12 relapsing lymph node lesions were contoured. Standardized uptake value (SUV) and Hounsfield unit (HU) values were included in the volumes contoured on coregistered basal and interim scans and included in a database. A linear regression model was used to identify the predictor of relapse at the lesion level. The support vector machine analysis and bootstrap approach were used to determine the model capability. The predictive models were presented as nomograms on the basis of basal or both basal and interim studies. SUV at the basal/interim study and basal HU values were predictors of a poor prognosis. In particular, the higher points were associated with lower values of SUV and HU at baseline and the higher values of SUV at the interim study. Using the bootstrap and support vector machine approach, the cut-off of the model increased up to 89%.ConclusionThe novel tool enables estimation of the risk of tumor relapse after chemotherapy in HL patients on the basis of basal and interim PET/CT scans including SUV and densitometric information
- …
