锥形束CT在鼻泪管阻塞性疾病辅助诊断中的应用价值

目的 探讨锥形束CT(CBCT)在鼻泪管阻塞性疾病辅助诊断中的应用价值.方法 选取2018年1月至2020年8月在中国人民解放军总医院眼科门诊就诊的鼻泪管阻塞性疾病患者104例,按随机数字表法分为观察组及对照组,各52例,观察组患者采用CBCT检查鼻泪管,对照组采用CT泪道造影检查鼻泪管.观察并比较两组患者鼻泪管的影像...     

Phloroglucinol (PG) purified from Ecklonia cava attenuates radiation-induced apoptosis in blood lymphocytes and splenocytes

Phloroglucinol (PG), a polyphenol compound of Eckloniacava known as brown algae abundant in Jeju island, has been proposed to exert the antioxidative and cytoprotective effects against oxidative stress. In this study, we confirmed that PG protected mice from damages caused by ionizing radiation and investigated its protection mechanism in detail. The result showed that PG increased the viability of splenocytes without cytotoxicity. Also, PG significantly enhanced the proliferation of splenocytes by limiting the increment of sub-G₁ DNA contents via the inhibition of reactive oxygen species production in 2 Gy-irradiated splenocytes. In addition, PG significantly decreased DNA damage and the number of apoptotic fragments in lymphocytes against oxidative stress. Also, PG increased the counts of endogenous spleen CFUs, compared with only ionizing radiation-irradiated mice. These results demonstrate the multi-faceted protection mechanisms of PG in mice against oxidative stress caused by ionizing radiation, providing the benefit of inhibiting apoptosis and strengthening hematopoiesis.     

烧伤小鼠血清对离体培养的骨髓基质细胞的影响

目的　研究小鼠烧伤血清对离体培养的骨髓基质细胞的影响。方法　利用流式细胞仪、HE染色等技术观察小鼠烧伤后不同时间的血清对小鼠骨髓基质细胞 (BMSC)贴壁率和基质祖细胞 (CFU F)集落形成的作用及对不同剂量的6 0 Coγ射线体外照射后的BMSC的影响。结果　小鼠烧伤后 1～ 11d的血清对基质细胞贴壁率和CFU F的形成主要表现为抑制作用 ,13～ 15d的血清主要表现为刺激作用。小鼠烧伤后 15d的血清可明显减少 5 0、70Gy照射后BMSC的凋亡和坏死。 结论　小鼠烧伤后不同时间的血清对BMSC的作用不同 ,可能与血清内细胞因子的变化有关。     

乳腺癌术后放疗放射性肺损伤的CT诊断

目的:探讨乳腺癌术后放疗放射性肺损伤的CT表现及诊断价值。方法:分析36例乳腺癌术后放疗发生放射性肺损伤患者的CT表现。结果:36例中急性放射性肺炎8例,表现为照射野范围内斑片状、片状密度增高灶或毛玻璃样改变;中间期15例,表现介于急性期与纤维化期之间,可同时见毛玻璃样改变、斑片状实变灶及纤维条索灶;纤维化期13例,表现为照射野范围内的纤维条索灶。结论:CT检查能清晰显示乳腺癌放疗后放射性肺损伤不同时期的特征表现,具有较高的临床价值。     

Quelle place pour la radiothérapie dans la prise en charge des cancers du pancréas localisés ?

At diagnosis, about 15% of patients with pancreatic cancer present with a resectable tumour, 50% have a metastatic tumour, and 25% a locally advanced tumor (non-metastatic but unresectable due to vascular invasion) or borderline resectable. Despite the technical progress made in the field of radiation therapy and the improvement of the efficacy of chemotherapy, the prognosis of these patients remains very poor. Recently, the role of radiation therapy in the management of pancreatic cancer has been much debated. This review aims to evaluate the role of radiation therapy for these patients.     

A change in treatment process with a modern record and verify system

Purpose: With the introduction of new treatment devices, such as a multileaf collimator (MLC) and dynamic wedge (DW), therapists have an increased responsibility to ensure correct treatment. Simultaneously, three-dimensional treatment planning (3DTP) has led to an increased number of portals and table movements. To counteract this challenge and maintain efficiency, a comprehensive record and verify (R&V) system is mandatory. We evaluated a commercial system (Varis) for reliability, ease of use, efficiency, and integration with our planning systems.

Methods and Materials: Some key elements of the Varis system are: integration of MLC and DW; auto setup for MLC, jaw, collimator, gantry, and limited table parameters; direct download of simulation beam data; and a regimented field scheduling system that prescribes all beam data for particular fractions. Evaluation of the system was driven by treatment time analysis, error rates, and an increased workload. These issues were governed by how we disseminated duties and how the system accommodated or changed our processes.

Results: Most data entry is performed by our dosimetry staff. Data can be downloaded from the simulator, but more patients now move from CT simulation and/or 3DTP to the treatment machine. Varis does not link to these systems. The physics staff confirms all entries to correct data entry errors. The workload for dosimetrists increased by an average of 8 minutes/patient entry; physics time increased by 7 minutes/patient entry; the weekly electronic chart check takes approximately 3 minutes/patient. Therapists who used Varis efficiently showed a slight decrease in treatment times, attributed to MLC integration and auto-setup. Some therapists experienced a decrease in efficiency, because of unfamiliarity and excess intervention. On a positive note, notable events have decreased by a factor of 10 since full initiation. Unfortunately, the remaining errors are often the result of a therapist relying on incorrect electronic information.

Conclusion: The Varis R&V system has had an impact on our clinic’s process and efficiency. Checking of all beam data and related field scheduling have helped reduce errors and misconceptions. We feel a dual-energy machine can be operated with two experienced therapists and an up-to-date R&V system more accurately and efficiently than with three therapists working without an integrated R&V. We anticipate future Varis releases will further promote efficiency and accuracy.     

鼻咽癌患者放疗后张口困难及其影响因素

目的：观察鼻咽癌患者放疗后张口困难的情况,探讨影响放射颞颌关节损务伤的有关因素。方法：选择352例常规分割放疗结束后≥6个月的鼻咽癌病例,所有病例颞颌关节受照总剂量为51．90－78．89Gy,总疗程35－141天。以门齿距为观察张口困难的指标,组间差异采用卡方检验,张口困难发生率与颞颌关节受照剂量关系采用二元曲线拟合,多变量分析采用Logistic回归。结果：全组张口困难发生率58．5％,重度张口困难发生率7．1％;颞颌关节受照剂量为51．90－60．00Gy、＞60．00－70．00Gy、＞70．00－78．89Gy的病人张口困难发生率分别为46．4％、53．5％和62．3％（P＝0．050）;放疗后坚持张口锻炼和未锻炼者发生率分别为51．6％和61．7％（P＝0．028）;年龄≤42岁组和＞42岁组发生率分别为54．1％和62．7％（P＝0．040）;颌关节受照剂量、张口锻炼与否和年龄大小是放射性颞颌关节损伤的独立影响因素。结论：鼻咽癌病人放疗后张口困难的发生率较高,颞颌关节受照剂量、张口锻炼和病人年龄是主要的影响因素。鼻咽靶区全部剂量都从两颞侧给予的照射方法应设法予以改进,放疗后应嘱咐病人坚持张口锻炼。     

低管电压结合AIDR技术在优化婴幼儿胸部CT扫描方案中的价值

目的 探讨低管电压结合自适应迭代剂量降低算法重建技术（AIDR）在优化婴幼儿胸部CT扫描方案中的应用价值.方法 回顾性分析笔者医院2013年1～5月间,从拟行胸部CT检查显示正常的,无贫血及其他疾病的0～1岁婴幼儿中随机选取40例,平均分成A与B两组,A组扫描时管电压为80kV,使用适应迭代剂量降低算法重建技术（AIDR）;B组为100kV,使用常规滤波反投影（FBP）重建技术.比较两组间气管分杈层面降主动脉的CT值与标准差（SD）、信噪比（SNR）、对比信噪比（CNR）、CT剂量指数（CTDI）及剂量长度乘积（DLP）.结果 两组的图像质量评分分别为4.56±0.48、4.61±0.45,差异无统计学意义（P＞0.05）.两组CT值、SD分别为50.36±5.74HU、12.57±4.48和45.31±4.71HU、10.61±3.48,A组高于B组,差异均无统计学意义（P＞0.05）.两组SNR和CNR分别为3.31±1.02、2.68±1.21和4.31±1.32、2.74±0.92,B组均高于A组,两组相比无统计学差异（P＞0.05）.两组的有效辐射剂量分别为1.79±0.316、5.04±0.19mSv,A组较B组辐射剂量明显降低,平均减少了65％.结论 320层CT在小儿胸部扫描采用80kV管电压扫描加ADIR重建,图像质量能达到诊断要求,且辐射剂量可显著降低.     

256层iCT联合iDose~4迭代重建在胸部低剂量CT中的应用价值

目的评价256层i CT联合i Dose4迭代重建技术在胸部低剂量CT扫描中的应用价值。方法将150名健康体检者随机分为常规剂量组(100m As)、低剂量50m As组和低剂量25m As组,分别采用100、50、25m As进行胸部CT扫描,100m As采用FBP重建作为常规对照组,两组低剂量扫描组均采用FBP及i Dose4对图像进行重建。比较不同毫安秒和重建算法的辐射剂量、CT图像噪声(MSD)、对比信噪比(CNR)、信噪比(SNR)以及主观图像质量。结果低剂量采用i Dose4组与常规对照组主观图像质量比较差异无统计学意义。50m As采用i Dose4重建图像的MSD、CNR及SNR与常规对照组差异有统计学意义(P0.05);25m As采用i Dose4与对照组比较差异无统计学意义。50m As组较常规对照组辐射剂量降低约53.3%,25m As相比对照组剂量降低76.4%。结论与常规剂量FBP重建相比,50和25 m As采用i Dose4重建能有效降低辐射剂量,同时不影响图像质量。