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21.
目的 利用MRI技术连续采集头颈部肿瘤患者吞咽时图像,观察并测量软腭、舌、喉的运动规律及最大活动度。方法 随机选取2018年7月-10月在中国医学科学院肿瘤医院接受调强放疗的原发头颈部恶性肿瘤20例患者,其中男17例、女3例,中位年龄58.5岁(28~78岁)。20例患者中鼻咽癌7例,口腔癌3例,口咽癌5例,下咽癌3例,鼻腔鼻旁窦2例。根据AJCC第八版分期Ⅰ-Ⅱ期患者2例,Ⅲ期8例,Ⅳ期10例。结果 吞咽时软腭向上移动移动距离为(1.06±0.31) cm且服从正态分布,向后移动距离为(0.83±0.24) cm且近似正态分布。舌体向后移动距离为(0.77±0.22) cm,且服从正态分布。含压舌板行图像采集患者舌上移位移为0,无压舌板患者舌体中位上移距离为1.23 cm (0.59~1.41 cm)。喉向上移动距离为(1.14±0.22) cm且服从正态分布,向前移动的中位距离为0.4 cm (0.27~0.90 cm)。结论 吞咽运动有可能发生于头颈部肿瘤患者放疗过程中,并引起大体肿瘤体积(GTV)及周围正常组织移动;因此在制定放疗计划时应注意GTV至PGTV的个体化外放距离,以保证肿瘤处方剂量。  相似文献   
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Contrast‐enhanced spectral mammography (CESM) has a number of uses including the work‐up of inconclusive findings on mammography, assessment of breast symptoms, cancer staging, evaluation of response to neoadjuvant chemotherapy and recently as an alternative to magnetic resonance imaging (MRI) in high‐risk screening. CESM can be swiftly incorporated into the workflow of busy breast clinics. We share our experiences with CESM at a large breast assessment centre in Western Australia.  相似文献   
25.
Objective: To evaluate the long-term clinical effect of high-intensity focussed ultrasound (HIFU) as a non-invasive modality for ablation of abdominal wall endometriosis (AWE) foci.

Methods: All women who were diagnosed with cutaneous endometriosis and underwent HIFU ablation and 4-year follow-up were included. Patient symptoms, imaging performed, HIFU ablation, recurrence, lesion location, size and number were collected and analyzed.

Results: A total of 51 women with 57 painful abdominal wall masses with a median volume of 4.00?cm3 and a mean age of 30.5±2.12 years were treated with HIFU. The main symptoms were a palpable painful abdominal mass (93%), protrusion of the skin (28.1%, 16) or lack of protrusion of the skin (71.9%, 41). Ultrasound was initially performed in 100% (51) of women, whereas 6% (3) required MRI examinations to distinguish the features and range of the masses. Ablation was performed with a median 300?s of sonication time, 40?min treatment time, 150?W of power and 41800?J of total energy to treat lesions that were a median volume of 3.83?cm3. No severe complications occurred, except in one patient with a first-degree skin burn, during the 48-month follow-up period. The pooled recurrence of cutaneous endometriosis occurred in 3.9% (2) of women.

Conclusion: The diagnosis of AWE should be confirmed with imaging of the lesion number, location, size and features before HIFU ablation. HIFU should be the first choice for the treatment of AWE as it is a non-invasive method, with high efficiency and safety and rapid postoperative recovery.  相似文献   

26.
日间手术在国外已有上百年的发展历史,现已成为欧美国家重要手术模式。我国于20世纪初开始开展日间手术,但目前尚未普及,发展不平衡问题比较突出,存在认识不清、开展不规范、与医保支付对接不畅等问题。日间手术是一种使国家、医院和病人三方均受益的新型手术模式。近年来,国家相关管理部门积极引导,开展日间手术的医院明显增多,可以预见,我国日间手术即将进入快速发展的新阶段。因此,有条件的医院可以从简单、易操作的病种开始,落实临床路径,积累经验,再逐步稳妥展开。在保证质量的前提下,不断拓展日间手术范围,提高三、四级手术比例。同时,积极与医保支付政策对接,采取灵活的方式,获得医保的支持,更好地促进我国日间手术的快速发展。  相似文献   
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目的 采用Meta分析对比四维子宫输卵管超声造影(4D-HyCoSy)与子宫输卵管造影(HSG)评估输卵管通畅性的效能。方法 系统搜索PubMed、Cochrane Library、Embase、Web of Science、中国生物医学文献数据库、中国知网、万方医学网及维普数据库中建库至今有关4D-HyCoSy和/或HSG评估输卵管通畅性的文献。由2名研究人员依据纳入标准和排除标准筛选文献并提取信息;分别计算4D-HyCoSy和HSG评估输卵管通畅性的合并敏感度(SEN)、特异度(SPE)及诊断比值比(DOR),绘制综合受试者工作特征(SROC)曲线,获得曲线下面积(AUC),并以Medcalc 19.1.1统计软件比较AUC。结果 最终纳入19篇文献、1 358例疑似输卵管因素导致不孕患者,其中4篇同时采用4D-HyCoSy及HSG评估输卵管通畅性,10篇仅以4D-HyCoSy评估,5篇仅以HSG评估。Meta分析结果显示,4D-HyCoSy评估输卵管通畅性的合并SEN、SPE及DOR分别为0.92[95%CI(0.91,0.94)]、0.91[95%CI(0.89,0.93)]及115.06[95%CI(54.23,224.10)];HSG评估输卵管通畅性的合并SEN、SPE及DOR分别为0.84[95%CI(0.81,0.87)]、0.80[95%CI(0.76,0.83)]及28.64[95%CI(10.08,81.35)]。4D-HyCoSy评估输卵管通畅性的AUC为0.98[95%CI(0.96,0.99)],HSG为0.93[95%CI(0.90,0.95)],差异有统计学意义(Z=6.97,P<0.01)。结论 4D-HyCoSy评估输卵管通畅性的效能高于HSG。  相似文献   
28.
BackgroundIn patients with melanoma, sentinel lymph node (SLN) status is pivotal for treatment decisions. Current routine for SLN detection combines Technetium99m (Tc99) lymphoscintigraphy and blue dye (BD). The primary aim of this study was to examine the feasibility of using a low dose of superparamagnetic iron oxide (SPIO) injected intracutaneously to detect and identify the SLN, and the secondary aim was to investigate if a low dose of SPIO would enable a preoperative MRI-evaluation of SLN status.MethodsPatients with melanoma of the extremities were eligible. Before surgery, a baseline MRI of the nodal basin was followed by an injection of a low dose (0.02–0.5 mL) of SPIO and then a second MRI (SPIO-MRI). Tc99 and BD was used in parallel and all nodes with a superparamagnetic and/or radioactive signal were harvested and analyzed.ResultsFifteen patients were included and the SLNB procedure was successful in all patients (27 SLNs removed). All superparamagnetic SLNs were visualized by MRI corresponding to the same nodes on scintigraphy. Micrometastatic deposits were identified in four SLNs taken from three patients, and SPIO-MRI correctly predicted two of the metastases. There was an association between MRI artefacts in the lymph node and the dose SPIO given.DiscussionIt is feasible to detect SLN in patients with melanoma using a low dose of SPIO injected intracutaneously compared with the standard dual technique. A low dose of SPIO reduces the lymph node MRI artefacts, opening up for a non-invasive assessment of SLN status in patients with cancer.  相似文献   
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Dynamic contrast-enhanced ultrasound (DCE-US) has been proposed as a powerful tool for cancer diagnosis by estimation of perfusion and dispersion parameters reflecting angiogenic vascular changes. This work was aimed at identifying which vascular features are reflected by the estimated perfusion and dispersion parameters through comparison with acoustic angiography (AA). AA is a high-resolution technique that allows quantification of vascular morphology. Three-dimensional AA and 2-D DCE-US bolus acquisitions were used to monitor the growth of fibrosarcoma tumors in nine rats. AA-derived vascular properties were analyzed along with DCE-US perfusion and dispersion to investigate the differences between tumor and control and their evolution in time. AA-derived microvascular density and DCE-US perfusion exhibited good agreement, confirmed by their spatial distributions. No vascular feature was correlated with dispersion. Yet, dispersion provided better cancer classification than perfusion. We therefore hypothesize that dispersion characterizes vessels that are smaller than those visible with AA.  相似文献   
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