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81.
PurposeThis study recruited 2 centers with expertise in treating pediatric brain tumors with robotic radiation delivery system photon therapy and proton therapy, respectively, to study the plan quality and dose deposition characteristics of robotic radiation delivery system photon therapy and intensity modulated proton therapy (IMPT) plans.Methods and MaterialsA total of 18 patients clinically treated with the robotic radiation delivery system were planned with IMPT. Cases were planned per the standard of care of each institution but respected the same planning objectives. The comparison included 3 aspects: plan quality, dose fall-off characteristics around the target volume, and the volume of the high-, intermediate-, and low-dose baths.ResultsAll robotic radiation delivery system and IMPT plans met the planning objectives. However, IMPT significantly reduced the maximum dose to organs at risk away from the planning target volume (PTV), such as the cochlea and eye (P < .05), and the mean dose to the normal brain (P < .05). No statistically significant difference was observed in the maximum dose to the optical pathway and brain stem. Robotic radiation delivery system plans demonstrated a sharper dose fall-off within 5 mm around the PTV (P < .05), whereas IMPT significantly lowered the dose to the normal tissue beyond 10 mm from the PTV (P < .05). The robotic radiation delivery system offers a smaller high-dose bath whereas IMPT offers a smaller low-dose bath (P < .05). However, the difference in intermediate dose is not statistically significant.ConclusionsIn general, robotic radiation delivery system plans exhibit reduced high-dose exposure to normal tissue, and IMPT plans have considerably smaller volumes of low-dose exposure with differences in medium-range dose baths increasingly favoring protons as tumor size increases.  相似文献   
82.
This study seeks to understand whether people substitute between recreational cannabis and conventional over-the-counter (OTC) sleep medications. UPC-level grocery store scanner data in a multivariable panel regression design were used to compare the change in the monthly market share of sleep aids with varying dispensary-based recreational cannabis access (existence, sales, and count) in Colorado counties between 12/2013 and 12/2014. We measured annually-differenced market shares for sleep aids as a portion of the overall OTC medication market, thus accounting for store-level demand shifts in OTC medication markets and seasonality, and used the monthly changes in stores’ sleep aid market share to control for short-term trends. Relative to the overall OTC medication market, sleep aid market shares were growing prior to recreational cannabis availability. The trend reverses (a 236% decrease) with dispensary entry (−0.33 percentage points, 95% CI −0.43 to −0.24, p < 0.01) from a mean market share growth of 0.14 ± 0.97. The magnitude of the market share decline increases as more dispensaries enter a county and with higher county-level cannabis sales. The negative associations are driven by diphenhydramine- and doxylamine-based sleep aids rather than herbal sleep aids and melatonin. These findings support survey evidence that many individuals use cannabis to treat insomnia, although sleep disturbances are not a specific qualifying condition under any U.S. state-level medical cannabis law. Investigations designed to measure the relative effectiveness and side effect profiles of conventional OTC sleep aids and cannabis-based products are urgently needed to improve treatment of sleep disturbances while minimizing potentially serious negative side effects.  相似文献   
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BackgroundWe compared the short-term oncologic and functional outcomes of salvage focal cryotherapy (SFC) with those of salvage total cryotherapy (STC) for radiotherapy (RT)-persistent/recurrent prostate cancer.Materials and MethodsWe queried the Cryo On-Line Database registry for men who had undergone SFC and STC of the prostate for RT-persistent or recurrent disease. Propensity score weighting was used to match age at treatment, presalvage therapy prostate-specific antigen level, Gleason sum, and presalvage cryotherapy androgen deprivation therapy status. The primary outcome was progression-free survival.ResultsA total of 385 men with biopsy-proven persistent or recurrent prostate cancer after primary RT were included in the present study. The median follow-up, age, prostate-specific antigen, and Gleason sum before salvage cryotherapy was 24.4 months (first and third quartile, 9.8 and 60.3), 70 years (first and third quartile, 66 and 74 years), 4 ng/dL (first and third quartile, 2.7 and 5.6 ng/dL), and 7 (first and third quartile, 6 and 8), respectively. After propensity score weighting, the difference in progression-free survival was not statistically significant between the patients who had undergone STC and those who had undergone SFC (79.8% vs. 76.98%; P = .11 on weighted log-rank test). SFC was associated with a lower probability of post-treatment transient urinary retention (5.6% vs. 22.4%; P < .001). No significant differences were found in the incidence of rectal fistula (1.4% vs. 3.8; P = .30), new-onset urinary incontinence within 12 months (9.3% vs. 15.1%; P = .19), or new-onset erectile dysfunction within 12 months (52.6% vs. 59.6%; P = .47) between the SFC and STC groups, respectively.ConclusionsSTC resulted in similar 2-year oncologic outcomes compared with SFC in the RT-persistent/recurrent disease population. However, the patients who had undergone SFC had a lower urinary retention rate compared with those who had undergone STC.  相似文献   
86.
Peer review is an essential tool for institutions and providers to meet the modern goals of safety and quality in health care. It is a mechanism that leads to a just culture within a health care institution whereby errors and complications are considered products of the system rather than isolated actions by an individual. The benefits and potential drawbacks of peer review are outlined in this review with a special emphasis on the interface between peer review and principles of medical ethics. It is argued that peer review, in the ideal setting, is founded upon the principles of beneficence and justice, and to varying levels on non-maleficence and autonomy.  相似文献   
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88.
《Radiography》2020,26(4):e195-e200
IntroductionAdverse events in radiology are quite rare, but they do occur. Radiation safety regulations and the law obligate organizations to report certain adverse events, harm and near misses, especially events related to patients' health and safety. The aim of this study was to describe and analyse incidents related to radiation safety issues reported in Finland.MethodsThe data were collected from incident reports documented by radiology personnel concerning notifications of abnormal events in medical imaging made to the Radiation and Nuclear Safety Authority between 2010 and 2017. During these eight years, 312 reports were submitted. Only events reported from radiology departments were included; nuclear medicine, radiotherapy and animal radiology cases were excluded. The final number of reports was 293 (94%).ResultsThe majority of the 293 approved reports were related to computed tomography (CT, 68.3%) and to X-ray examinations (27.6%). Altogether 82.9% of those irradiated were adults, most of whom were exposed to unnecessary radiation through CT (86.5%), 5.5% were children, and 4.4% pregnant women. The most common effective dose of unnecessary radiation was 1 mSv or less (89.7% of all examinations). The highest effective doses were reported in CT (from under 1 mSv–20 mSv and above). The reasons for the adverse events were incorrect identification (32%), incorrect procedure, site or side (30%); and human errors or errors of knowledge (20%).ConclusionAdverse events occurred especially in CT examinations. It is important to collect and analyse incident data, assess the harmful events, learn from them and aim to reduce adverse events.Implications for practiceThis study emphasizes the need for radiological personnel to obtain evidence-based information on adverse events and focus on training to improve patient safety.  相似文献   
89.
Background and aimPatient decision aids for oncological treatment options, provide information on the effect on recurrence rates and/or survival benefit, and on side-effects and/or burden of different treatment options. However, often uncertainty exists around the probability estimates for recurrence/survival and side-effects which is too relevant to be ignored. Evidence is lacking on the best way to communicate these uncertainties. The aim of this study is to develop a method to incorporate uncertainties in a patient decision aid for breast cancer patients to support their decision on radiotherapy.MethodsFirstly, qualitative interviews were held with patients and health care professionals. Secondly, in the development phase, thinking aloud sessions were organized with four patients and 12 health care professionals, individual and group-wise.ResultsConsensus was reached on a pictograph illustrating the whole range of uncertainty for local recurrence risks, in combination with textual explanation that a more exact personalized risk would be given by their own physician. The pictograph consisted of 100 female icons in a 10 x 10 array. Icons with a stepwise gradient color indicated the uncertainty margin. The prevalence and severity of possible side-effects were explained using verbal labels.ConclusionsWe developed a novel way of visualizing uncertainties in recurrence rates in a patient decision aid. The effect of this way of communicating risk uncertainty is currently being tested in the BRASA study (NCT03375801).  相似文献   
90.
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