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981.
PurposeTo evaluate the clinical outcome after CT-guided interstitial high-dose-rate (HDR) brachytherapy for dose escalation in the radiotherapy treatment of inoperable locally advanced non–small-cell lung cancer (NSCLC).Methods and MaterialsFrom 2005 to 2015, 16 patients with unresectable NSCLC were treated. Median age was 65.7 years (range, 52–86). The median tumor volume was 95.3 cm3 (range, 20.0–2000.0). The median prescribed HDR was 15.0 Gy (range, 7.0–32.0) delivered in twice-daily fractions of 6.0–8.0 Gy in 4 patients and in once-daily fractions of 7.0–15.0 Gy in 12 patients, respectively.ResultsAfter a median followup of 12.5 months, median overall survival and local control was 12.9 and 24.9 months, respectively. The corresponding median overall survival and local control rates at 1, 2, and 3 years were 56.2%, 37.5%, and 12.5% as well as 68.9%, 57.4%, and 43%, respectively. Apart from one Grade 1 cough episode persisting for 1 week and one patient developing a minor hemopneumothorax requiring no postprocedural drainage, no other adverse events were recorded.ConclusionsCT-guided interstitial HDR brachytherapy is a safe modality for radiation dose escalation which may play a role in the definitive radiotherapy treatment of locally advanced NSCLC.  相似文献   
982.
ObjectiveHigh-value care guidelines from multiple medical societies recommend against imaging for the initial evaluation of low back pain in the absence of red flag symptoms. We aimed to determine the current temporal and geographic landscape of imaging ordering patterns for this indication among US primary care providers.MethodsUsing a national commercial insurance claims database, we identified patients between 18 and 64 years old who presented to a primary care provider for an initial evaluation of low back pain between 2011 and 2016. Patients were identified via International Classification of Diseases codes, and the use of diagnostic imaging was identified by Current Procedural Terminology codes. Geographic regions were based on the location of patient residence.ResultsOverall, 627,118 encounters met inclusion criteria. Imaging acquisitions increased over time, from 14% of encounters in 2011 to 16% in 2016 (P < .01). Radiographs represented 96% of ordered imaging, CT 2%, and MRI 3%. The likelihood of having any imaging for low back pain varied significantly by US census region and by US state (P < .01). The greatest use of imaging was in the Midwest (13.9%) and the South (18.5%), and lowest in the Northeast and West (6.2% and 13.6%).DiscussionImaging utilization for the initial evaluation of low back pain by primary care providers has increased on a national level from 2011 to 2016, largely represented by radiographs. Significant regional variation also exists. Encouragingly, the use of advanced imaging has remained at a low level in the primary care setting (<1.0%).  相似文献   
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ObjectiveTo describe imaging utilization, outcomes, and cost in the management of intussusception between 2010 and 2017 in pediatric hospitals in the United States.MethodsAll children (under 18 years of age) with a primary diagnosis of intussusception in a large administrative database were identified. Demographics, imaging, and costs were described.ResultsThere were 17,032 children (63.3% boys, 36.7% girls, mean age: 3.2 years) that had 20,655 hospital encounters for intussusception, and 88.5% were <5 years of age. The average length of stay was 2.8 days (median: 1 day), with rates of intensive care unit admission, 3.7%; 90-day readmission, 10.5%; and mortality, 0.2%. The surgical rate was 19.6%, and 93.5% (n = 19,301) of patients underwent imaging: 87.2% (n = 16,822) received ultrasound, 69.1% (n = 13,329) had fluoroscopy, 59% (n = 11,380) had abdominal radiographs, and 8.8% (n = 1,696) had CT. The reduction success rate for fluoroscopy was 77.9%. Surgery was more common in rural patients (26.8% versus 18.7% in urban patients, P < .001). Median encounter costs were $2,675 (interquartile range: $1,637-$5,465). Imaging cost represented a quarter (median $680, interquartile range: $372-1,069) of all costs. Higher costs (median) were associated with longer length of stay (<3 days: $858 versus >3 days: $5,342; use of CT ($4,168 versus $943 in patients without a CT), and surgery ($4,434 versus $860 without surgery).ConclusionThe management of intussusception is mainly nonsurgical, most frequently involving imaging with ultrasound and fluoroscopy, and resulting in excellent outcomes in the great majority of the cases. Despite playing a central role for diagnosis and management, imaging only represents a fraction of total cost.  相似文献   
984.
PurposeTo assess temporal trends and utilization patterns of diagnostic imaging performed for substance use disorder (SUD)-related indications in an academic radiology emergency department (ED).MethodsRetrospective analyses of ED imaging examinations acquired from 2005 to 2015 were performed. Imaging examinations performed for suspected SUD-related indications, based on the order history, were compared with those without a SUD-related indication. Unadjusted analyses comparing demographic and imaging characteristics between SUD-related versus non-SUD-related indications used Wilcoxon and Pearson’s χ2 tests. Multivariable logistic regression models, within each imaging modality subgroup and combined, were employed to examine the odds of imaging examinations having an SUD-related indication as a function of demographic and imaging characteristics.ResultsAmong 938,245 examinations, 0.17% had an SUD-related indication. Patients with SUD-related indications were younger (mean 37.2 ± 11.1 versus 53.5 ± 22.4, P < .001) and more commonly male (65% versus 52%, P < .001). The proportions of MR (17%), spine (17%), and extremities (33%) studies performed for SUD-related indications were larger among SUD than non-SUD indications (6%, 8%, 26%, respectively, all P < .001). Regression analysis demonstrated the odds of acquiring an ED imaging examination with an SUD-related indication significantly increased over time (P < .001, adjusted odds ratio [aOR] = 1.06), which was most pronounced among MR (P < .001, aOR = 1.23). For all regression models, younger age, male gender, and body part being imaged were identified as independent predictors of an SUD-related indication for ED imaging.ConclusionImaging performed for an SUD-related indication represented a small but increasing subset of overall ED imaging. Utilization of MR for SUD-related indications significantly outpaced growth of MR without SUD-related indications.  相似文献   
985.
ObjectiveThe objective of this study was to assess the computed tomography (CT) findings of gastric schwannoma (GS) and identify the difference between large (> 5 cm) and small (≤ 5 cm) GS.Materials and MethodsCT findings of 38 pathologically proven cases of GSs were retrospectively reviewed. The CT evaluation of GS included categorical variables (location, contour, growth pattern, enhancement pattern, necrosis, ulceration, calcification, and lymph nodes) and continuous variables (size, CT value of 3 phases, and enhancement degree). The lesion was divided into 2 groups (large [> 5 cm] and small [≤ 5 cm] GS) according to the tumor size. The Fisher exact test was used for categorical variables and the Student t or Mann-Whitney U test for continuous variables.ResultsOf the 38 patients, there were 32 women and 6 men. The median age was 54.5 years (range 39–79). Most of patients (65.8%, [25 of 38]) had nonspecific gastrointestinal symptoms such as abdominal or gastric pain, fullness and discomfort, bleeding, and melena. The tumors were mainly located in the stomach body (71.1% [27 of 38]), and the mean diameter was 3.7 cm (range 1.5 cm-10.3 cm), of which included large (> 5 cm) (n = 8) and small (≤ 5 cm) (n = 30). All of the GSs were benign, 9 of whom had palpable perigastric lymph nodes, which confirmed by pathology for the reactive inflammatory hyperplasia. Growth pattern, pattern of enhancement, necrosis, calcification, surface ulceration, and lymph node in the CT images were found to be significant variables for differentiating large (> 5 cm) and small (≤ 5 cm) GS (P < .05).ConclusionGSs were predominantly located at the gastric body and occurred most frequently in women between the ages of 40–70 years, and showed gradual enhancement after contrast enhancement. Palpable perigastric lymph nodes could not be considered as malignant factor of GS. There 7 computed CT criteria are significant difference between large (> 5 cm) and small (≤ 5 cm) GS.  相似文献   
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