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41.
PurposeTo evaluate the volume reduction rate (VRR) of thyroid nodules over a long period of time after radiofrequency (RF) ablation treatment in both solid and mixed nodules; to determine ablation parameters; and to evaluate complications and success rates and safety of RF ablation.Material and MethodsIn this prospective study, 24 patients (83% females and 17% males; age 50.17 ± 13.6 years) underwent ultrasound-guided percutaneous RF ablation of benign thyroid nodules with radiologic follow-up at 1, 3, 6, 12, 24, and 36 months after treatment. All patients presented with compressive or cosmetic complaints and with Thyroid Imaging Reporting and Data System 1 or 2 nodules under ultrasound and were confirmed to be Bethesda Category II after 2 fine-needle aspirations.ResultsA total of 24 nodules (54.2% solid, 37.5% solid predominance, and 8.3% cystic predominance) were included in this study. Significant results in VRR (%) were found at 24 months and 36 months of 69.92 ± 19.23 and 76.84 ± 15.92, respectively. Furthermore, a logarithmic relationship was found when VRR was plotted over time, in both solid and mixed nodules. No correlations were found with any of the ablation parameters. The success rate reached 72.22% at 12 months, and the total complication rate was 16.67% (12.5% minor complications and 4.2% major complications—1 laryngeal nerve palsy), reaching an 83.3% safety.ConclusionsRF ablation can be an alternative treatment modality in the management of benign symptomatic thyroid nodules. The results show that it is a safe and effective treatment if trans-isthmic approach and moving-shot techniques are correctly followed.  相似文献   
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PurposeTo evaluate efficacy and safety of radiofrequency (RF) ablation for parotid Warthin tumor.Materials and MethodsFrom September 2016 to August 2017, 7 consecutive patients with biopsy-proven parotid Warthin tumors who did not undergo surgery presented with symptoms or cosmetic concerns and underwent US-guided percutaneous RF ablation treatment. RF ablation procedures were performed using the moving shot technique. US, contrast-enhanced CT, or MR imaging was performed 6–12 months after each procedure. Complications and cosmetic scale improvement after RF ablation were also evaluated.ResultsThere was a significant reduction in mean tumor volume from 14.6 cm3 ± 13.1 (range, 1.9–35.5 cm3) to 0.8 cm3 ± 0.5 (range, 0.2–1.54 cm3) and a mean cosmetic scale improvement (from 4 to 1) on imaging studies 6–12 months after RF ablation compared with before RF ablation (P < .05). Volume reduction ratios at 1–2 months, 5–6 months, and 10–12 months after RF ablation were 51.2% ± 18.1%, 87.8% ± 10.6%, and 94.3% ± 2.0%. There was no facial nerve injury. One patient with parotitis and hematoma recovered in 1 week.ConclusionsRF ablation using the moving shot technique could be an effective and safe alternative treatment for parotid tail Warthin tumors in patients unsuitable for or unwilling to undergo surgical resection.  相似文献   
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医用磁共振系统是由磁体构造、波谱分析和计算机成像等多种技术融为一体的医疗成像设备。该文通过对磁共振射频系统与其体部线圈的相互作用进行分析,进一步探讨造成同一平板线圈连续烧毁的原因,并给出相应的维护措施,以此保证设备的正常工作。  相似文献   
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Lee HL  Ryu JH  Wittmer MH  Hartman TE  Lymp JF  Tazelaar HD  Limper AH 《Chest》2005,127(6):2034-2041
STUDY OBJECTIVES: Familial idiopathic pulmonary fibrosis (FIPF) has been defined as idiopathic pulmonary fibrosis (IPF) occurring in two or more members of a family. The clinical course of FIPF has not been fully defined. Accordingly, the current study was undertaken to establish clinical, radiologic, and histologic features, and survival in a consecutive series of patients with FIPF. DESIGN: Retrospective analysis of clinical, radiologic, and pathologic data from a consecutive series of patients with FIPF who were seen at Mayo Medical Center. Survival in patients with FIPF was contrasted to that of previously characterized patients with nonfamilial IPF who were evaluated at our institution. SETTING: Tertiary referral medical center. PATIENTS: We screened 47 patients and family members with FIPF from 15 families who were identified between the years 1992 and 2002. We further analyzed the subgroup of FIPF patients that was composed of 27 patients from 15 families in whom the complete clinical course was monitored at our institution. MEASUREMENTS: All patients exhibited clinical features that were compatible with IPF and either compatible high-resolution CT (HRCT) scan findings or histologic evidence of usual interstitial pneumonia. Clinical data, including symptoms, physical findings, HRCT scan findings, lung function test results, biopsy results, and survival were abstracted from the clinical records. RESULTS: Compared to patients with nonfamilial IPF, patients with FIPF did not demonstrate any notable differences in clinical, radiologic, or pathologic features. We observed that the total number of affected members in a family with FIPF was a significant risk factor for earlier mortality (p = 0.0157; hazard ratio, 1.434). Overall, however, patients with FIPF had a statistically similar outcome to those patients with nonfamilial IPF. CONCLUSIONS: Although uncommon, FIPF represents a distinct syndrome, which has clinical features and patient survival rates that are similar to those of nonfamilial IPF.  相似文献   
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The objective of this study was to investigate the effects of the combined RF radiation (837 MHz CDMA plus 1950 MHz WCDMA) signal on levels of intracellular reactive oxygen species (ROS) in neuronal cells. Exposure of the combined RF signal was conducted at specific absorption rate values of 2 W/kg of CDMA plus 2 W/kg of WCDMA for 2 h. Co-exposure to combined RF radiation with either H2O2 or menadione was also performed. The experimental exposure groups were incubator control, sham-exposed, combined RF radiation-exposed with or without either H2O2 or menadione groups. The intracellular ROS level was measured by flow cytometry using the fluorescent probe dichlorofluorescein diacetate. Intracellular ROS levels were not consistently affected by combined RF radiation exposure alone in a time-dependent manner in U87, PC12 or SH-SY5Y cells. In neuronal cells exposed to combined RF radiation with either H2O2 or menadione, intracellular ROS levels showed no statically significant alteration compared with exposure to menadione or H2O2 alone. These findings indicate that neither combined RF radiation alone nor combined RF radiation with menadione or H2O2 influences the intracellular ROS level in neuronal cells such as U87, PC12 or SH-SY5Y.  相似文献   
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