低管电压扫描技术用于CT引导下冷冻消融治疗肝癌的可行性

目的观察低管电压扫描技术用于CT引导下冷冻消融治疗肝癌的可行性。方法以21例接受常规CT扫描(管电压120 kV)引导下冷冻消融的肝癌患者(A组),前瞻性对23例肝癌患者行低管电压(100 kV)CT引导下冷冻消融(B组)。对2组均于消融治疗前、后以自动管电流模式(50~450 mA)行CT扫描,并以自适应统计迭代重建(ASIR)算法(重建百分比均为40%)重建图像;对比2组治疗前、后CT图像质量主、客观评价结果,以及疗效和患者辐射剂量[容积CT剂量指数(CTDIvol)]。结果组间CT图像质量主、客观评价结果及疗效差异均无统计学意义(P均>0.05)。治疗前、后A组患者CTDIvol均显著高于B组(P均<0.001)。结论低管电压扫描技术可用于CT引导下冷冻消融治疗肝癌;联合ASIR算法可在保证图像质量和不影响评估冷冻消融效果的同时降低辐射剂量。

基于功能核磁共振成像技术对NAION患者脑功能变化的研究

目的探讨非动脉炎性前部缺血性视神经病变(NAION)患者功能核磁共振成像(BOLD-fMRI)的变化特征。方法纳入2018年1月—2019年1月就诊于北京中医药大学东方医院眼科的NAION患者20例作为观察组。同时纳入20例性别、年龄相匹配的同医院同时期体检的健康人作为对照组。所有对象入组后,均进行BOLD-fMRI检查,选用静息态的数据处理软件进行数据处理及分析,获得BOLD-fMRI大脑低频振幅(ALFF),用峰值T表示,总结NAION患者BOLD-fMRI的变化特征。结果与对照组比较,观察组初级视觉皮层(即布罗德曼17区)、右脑岛、额中回区域的峰值T均为负值,表明ALFF降低;观察组脑桥、舌状回、楔前叶、中央旁小叶区域的峰值T均为正值,表明ALFF增加。结论NAION患者部分脑区功能活动异常,默认网络(DMN)功能障碍,这可能利于NAION的早期诊断。

葡萄糖转运蛋白1型在脑肿瘤中的表达及意义

目的探讨葡萄糖转运蛋白1型(Glucose transporter-1,GLUT1)在脑肿瘤中的表达及其意义。方法收集55例颅脑手术标本,包括46例脑肿瘤患者和9例正常脑组织,采用单克隆抗体的GLUT1免疫组织化学SP法进行染色。结果7例低度恶性胶质瘤中的3例和全部13例高度恶性胶质瘤不同程度的表达GLUT1;10例良性脑膜瘤中的3例和全部5例恶性脑膜瘤为阳性表达;6例垂体瘤中的3例和5例表皮样囊肿也异常表达;所有正常脑组织均未见表达。结论四种脑肿瘤均可不同程度表达GLUT1,尤其在恶性肿瘤为明显,其与脑肿瘤的恶性程度相关。

能谱CT单能量结合ASiR技术对腹部静脉成像质量的优化研究

目的:比较不同水平的自适应迭代重建算法(ASiR)在腹部静脉血管最佳单能量成像中的图像质量,优化腹部静脉血管的成像参数。方法:回顾性分析上腹部能谱增强扫描检查患者30例。通过后处理工作站测量出最佳单能量值,分别用30%ASiR、40%ASiR及50%ASiR算法进行重建,分析比较三组图像及混合能量组图像中各静脉的CT值、图像噪声SDn、CNR及SNR。由放射科两名资深诊断医师采用双盲法对四组数据进行主观评估并记录评分。结果:混合能量组与其他三组在CT值、SDn、CNR及SNR均具有统计学差异(P <0.01)。30%ASiR组、40%ASiR组及50%ASiR组图像在CT值方面均无统计学差异(P> 0.05)。在门静脉主干、肠系膜上静脉及脾静脉30%ASiR组与50%ASiR组之间的SDn、CNR、SNR均有统计学差异(P <0.05),30%ASiR组与40%ASiR组,40%ASiR组与50%ASiR组之间的SDn、CNR、SNR均无统计学差异(P> 0.05);在下腔静脉主干、左肾静脉、右肾静脉、肝左静脉、肝中静脉和肝右静脉30%ASiR组与50%ASiR组之间的SDn、CNR均有统计学差异(P <0.05),30%ASiR组与40%ASiR组,40%ASiR组与50%ASiR组之间的SDn、CNR均无统计学差异(P> 0.05),三组图像之间的SNR均有统计学差异(P <0.05)。结论:最佳单能量(65 keV)+40%ASiR在腹部静脉血管的成像质量较其他三组有所提高,可以在临床腹部静脉血管成像方面广泛应用。

Re-canalized stenostic rabbit nasolacrimal duct by the ^(125)I radioactive probing:Affecting Bcl-2 and Bax protein expression

To evaluate the ^(125)I radioactive probing re-canalizing stenostic nasolacrimal duct,the nasolacrimal duct stenosis models in epithelium and connective tissues are experimentally structured by inbred white rabbits(New Zealand),including the nasolacrimal duct stenosis,the mechanical probing with outer layer of thermoplastic tube,and the ^(125)I radioactive probing with the ^(125)I seeds sealing into the thermoplastic tube.After re-canalized for four weeks, tissue specimens from bilateral nasolacrimal ducts are obtained,and the Bcl-2 and Bax protein expression levels are evaluated by immunohistochemical staining analysis.Comparing with the blank control,the expression levels of the Bcl-2 and Bax in the nasolacrimal duct stenosis and the mechanical probing are significantly up-/down-regulated(p<0.05),but in the ^(125)I radioactive probing are down-/up-regulated(p<0.05) and can be used to re-canalize the stenostic lacrimal passage.The results show that the ^(125)I radioactive probing is a therapeutical mechanism for radioactive probing strategy for treating nasolacrimal duct stenosis to induce cell apoptosis.

MR扩散张量成像评估非动脉炎性前部缺血性视神经病变进展程度的价值

目的探讨MR扩散张量成像（DTI）定量参数评估非动脉炎性前部缺血性视神经病变（NAION）进展程度的价值。方法收集2015年6月至2017年8月，确诊为NAION的38例患者的56只眼作为NAION组，根据发病时间分为急性期17只眼、进展期16只眼、慢性期23只眼；按照年龄、性别匹配原则，纳入38名健康志愿者的56只眼作为对照组。所有受试者均行MR及DTI检查，对原始图像后处理后获得平均扩散率（MD）、平行扩散率（λ//）、垂直扩散率（λ┴）、部分各向异性（FA）、纤维束长度（Length）值。采用独立样本t检验比较NAION组与对照组间各参数值的差异；采用单因素方差分析比较NAION组不同时期患者间各参数值的差异。 结果NAION组的FA、Length值分别为0.20±0.11、（5.85±0.92）mm，较对照组[0.31±0.12、（65.11±6.89）mm]降低，差异均有统计学意义（t=－4.28、－5.25，P〈0.05）；NAION组MD、λ┴值分别为（0.16±0.04）×10-3、（0.16±0.05）×10-3 mm2/s，较对照组[（0.10±0.04）×10-3、（0.09±0.03）×10-3 mm2/s]升高，差异均有统计学意义（t=6.83、7.10，P〈0.05）。NAION组急性期、进展期和慢性期患者分别与相应的对照组相比，各期的FA、Length值降低，MD、λ┴值升高，差异均有统计学意义（P〈0.05）。NAION组急性期、进展期及慢性期患者间FA值的差异有统计学意义（F=10.88，P〈0.05），MD、λ//、λ┴及Length值的差异无统计学意义（F值分别为0.23、0.64、0.33、1.38；P值分别为0.79、0.54、0.72和0.27）。NAION组急性期与慢性期、进展期与慢性期之间FA值的差异均有统计学意义（P〈0.05）。结论DTI定量参数可用于评估NAION患者不同进展阶段的视神经损害程度。

Imaging and histopathological findings of lacrimal sac lymphoma

Background Lymphoma of the lacrimal sac is rare,often misdiagnosed clinically.This study aimed to investigate the imaging features of these tumors and provide suggestions to aid the diagnosis.Methods In this retrospective study,five cases were assessed according to magnetic resonance imaging （MRI）,computed tomography （CT）,and pathological findings.All five patients underwent MRI and contrast-enhanced T1-weighted imaging （CE-T1WI）,of which four patients underwent dynamic contrast-enhanced （DCE） MRI and three patients underwent CT.Results Four cases and one case had a lymphoma in left and right medial canthus,respectively.Soft tissue surrounding the eyelids,subcutaneous tissue in the nasal dorsum,and involvement of the entire nasolacrimal canal were demonstrated in all five lesions.In two cases,the mass invaded the extraconal space.In one case,the mass invaded the adjacent medial rectus muscle and nasal area.Well-defined margins were observed in three cases and ill-defined margins in two cases.All cases showed homogeneous isointense lesions on T1Wl.Four cases showed homogeneous isointensity and one case demonstrated heterogeneous isointensity on T2Wl.After contrast injection,the lesion showed slight homogeneous isointensity and moderate enhancement in four cases and heterogeneous isointensity and moderate enhancement in one case.In the four patients who underwent DCE-MRI,a plateau pattern was revealed in three cases and washout pattern in one case.In the three cases who underwent CT,two cases had isointense and one case had hyperintense lesions.The lacrimal duct was remodeled and the surrounding bone compressed.Conclusions Tumors of the lacrimal sac showed homogeneous and isointense patterns on T1WI and T2WI with mildto-moderate enhancement and a plateau pattern on DCE-MRI.CT showed remodeling of the lacrimal duct with bone compression.

Study of MR diffusion tensor imaging to monitor the damage degree of optic nerve in non-arteritic anterior ischemic optic neuropathy

Objective To study the feasibility and value of magnetic resonance diffusion tensor imaging(DTI)to monitor non-arteritic anterior ischemic optic neuropathy(NAION).Methods Thirty eight NAION patients(56 eyes)were divided into acute period in 17 eyes,progressive period in 16 eyes and chronic period in 23 eyes at the base of onset time.According to matching principle,56 eyes in 38 normal controls(NCs)were enrolled.All the patients and NCs underwent MR and DTI scan.The raw data were processed by two experienced radiologists,mean diffusivity(MD),axial diffusivities(λ∥),radial diffusivities(λ⊥),fractional anisotropy(FA)and Length value were got.The independent sample t test was used for the parameter values between the NAION group and the NCs group.A single factor variance analysis was used to compare the parameters among different stages of NAION group.Results Compared to the NCs group,the values of FA and Length in NAION group were reduced [0.20±0.11 vs 0.31±0.12,(5.85±0.92)vs(65.11±6.89)mm ],and the differences were statistically significant(t=-4.28,-5.25;P<0.05).The values of MD and λ⊥were increased [(0.16±0.04)×10^-3 vs(0.10±0.04)×10^-3mm^2/s,(0.16±0.05)×10^-3 vs(0.09±0.03)×10^-3mm^2/s] in NAION group and the differences were statistically significant(t=6.83,7.10;P<0.05).The value of FA and Length in acute period,progressive period and chronic period of the NAION group decreased differently compared to the NCs group.At the same time,the value of MD value and λ⊥in the three periods of the NAION group increased compared to the NCs group and the differences were statistically significant(P<0.05).The values of FA between the acute period,the progressive period,and the chronic period of NAION group were statistically significant(F=10.88,P<0.05).However,no significant differences were found in the values of MD,λ⊥and Length of the NAION group(F=0.23,0.64,0.33,1.38;P=0.79,0.54,0.72,0.27).Conclusion The parameters of DTI can be used to monitor the damage of optic nerve and development in NAION.