非高密度脂蛋白胆固醇水平与冠心病患者冠状动脉病变Gensini评分的相关性研究

目的 探讨非高密度脂蛋白胆固醇水平(non-HDL-C)与冠心病(CHD)患者冠状动脉病变Gensini评分的关系及临床意义。方法 对225例疑诊或既往临床诊断CHD患者予以冠状动脉造影(CAG),将造影阴性的39例作为对照组(HC组),造影阳性的186例患者诊断为CHD,结合临床特点分为心绞痛组(AP组)122例和心肌梗死组(AMI组)64例。采用Gensini评分对冠状动脉病变程度评分,测定患者全套血脂水平,探讨non-HDL-C及相关脂质成分与冠状动脉病变程度Gensini评分的相关性;同时对他汀类药物强化降脂达标,低密度脂蛋白胆固醇(LDL-C)<1.80 mmol/L的AP组患者进行non-HDL-C与冠状动脉病变程度Gensini评分的亚组分析。结果 AMI组non-HDL-C水平高于AP组及HC组,AP组non-HDL-C水平高于HC组,差异均有统计学意义(P<0.05);CHD患者non-HDL-C水平与Gensini评分呈正相关(r=0.562,P<0.05);LDL-C控制达标的AP组患者,高non-HDL-C组(≥2.60 mmol/L)比低non-HDL-C组(<2.60 mmol/L)Gensini评分明显升高,差异均有统计学意义(P<0.05)。结论 non-HDL-C与冠状动脉病变程度密切相关,non-HDL-C在评估LDL-C控制达标患者的冠状动脉病变程度及再发心血管事件风险上有一定价值,可作为LDL-C达标后心血管残余风险新的观察指标。     

不同影像检查在乳腺结构扭曲中的研究进展

我国乳腺癌的发病率占女性恶性肿瘤疾病的首位,结构扭曲病变(architectural distortion,AD)作为触诊阴性乳腺癌的第三最常见影像学表现,也是乳腺癌最早出现的征象,具有重要的临床价值。AD具有较高的漏诊率及假阳性率。本文通过查阅文献,针对超声、乳腺X线摄影、乳腺数字三维断层摄影技术及核磁共振成像技术在乳腺结构扭曲病变中的研究进展及优缺点进行分析,进一步指导科学研究及临床工作。     

Free Water Loss–induced Heterogeneous Residual Strain and Reduced Fatigue Resistance in Root Dentin: A 3-dimensional Digital Image Correlation Analysis

IntroductionThis study evaluated free water loss–induced residual strain with and without axial compressive loading and assessed the mechanical effect of cyclic loading in fully hydrated and partially dehydrated root dentin.MethodsRoot dentin sections prepared from freshly extracted human premolars were used. Customized 3-dimensional digital image correlation was used to qualitatively and quantitatively analyze the residual strain induced by 2 hours of free water loss in different regions of root dentin. Residual strain in partially dehydrated root dentin during axial compressive loading was also analyzed using 3-dimensional digital image correlation. The effect of cyclic loading on load to fracture in fully hydrated and partially dehydrated dentin and their fractography were analyzed using micro–computed tomographic imaging.ResultsFree water loss resulted in a heterogeneous distribution of residual strain and an overall formation of residual compressive strain with areas of tensile strain localized to the root canal and outer dentin. More residual compressive strain was observed in the apical dentin compared with the cervical dentin (P < .05), and more residual shear strain was observed in outer dentin compared with inner dentin (P < .05). Axial loading resulted in an increase in the load-induced compressive strain in the direction perpendicular to dentinal tubules (P < .05). Fully hydrated roots displayed a higher mean (P < .05) and median (P < .05) number of cycles to fracture with microcracks characteristic of toughness.ConclusionsAfter free water loss, root dentin displayed an increased formation of heterogenous residual strain, which resulted in increased axial compressive load-induced strain and a decreased resistance to fatigue failure. The effect of free water loss in the loss of mechanical integrity of root-filled teeth needs further investigation.     

冠状动脉心肌桥的临床特点与治疗

目的探讨冠状动脉心肌桥的冠脉造影特点、临床意义及治疗方法。方法回顾性分析293例冠状动脉造影中检出的8例心肌桥患者的临床资料。结果共检出心肌桥8例,均位于前降支,心肌桥发生率为2.7%,心肌桥长度8～25mm,平均14.5mm。依据Nobel分级法,Ⅰ级3例,Ⅱ级4例,Ⅲ级1例。1例Ⅲ级患者同时并发冠脉粥样硬化,病变位于回旋支中段,狭窄<50%。8例患者应用β受体阻滞剂或钙拮抗剂治疗后症状均明显缓解。结论选择性冠脉造影可用于心肌桥的诊断,心肌桥可能引起心肌缺血表现,应用β受体阻滞剂或钙拮抗剂等药物治疗有效。     

Robust rigid registration of retinal angiograms through optimization

Retinal fundus photographs are employed as standard diagnostic tools in ophthalmology. Serial photographs of the flow of fluorescein and indocyanine green (ICG) dye are used to determine the areas of the retinal lesions. For objective measurements of features, the registration of the images is a necessity. In this paper, we employ optimization techniques for registration with the help of 2-parameter translational motion model of retinal angiograms, based on non-linear pre-processing (Wiener filtering and morphological gradient) and computation of the similarity criteria for the alignment of the two gradient images for any given rigid transformation. The optimization methods are effectively employed to minimize the similarity criterion.

The presence of noise, the variations in the background and the temporal variation of the fluorescence level pose serious problems in obtaining a robust registration of the retinal images. Moreover, local search strategies are not robust in the case of ICG angiograms, even if one uses a multiresolution approach.

The present work makes a systematic comparison of different optimization techniques, namely the minimization method derived from the optical flow formulation, the Nelder-Mead local search and the HCIAC ant colony metaheuristic, each optimizing a similarity criterion for the gradient images. The impact of the resolution and median filtering of gradient image is studied and the robustness of the approaches is tested through experimental studies, performed on macular fluorescein and ICG angiographies.

Our proposed optimization techniques have shown interesting results especially for high resolution difficult registration problems. Moreover, this approach seems promising for affine (6-parameter motion model) or elastical registrations.     

64层螺旋CT在糖尿病下肢动脉硬化闭塞症中的诊断价值

目的评价64层螺旋CT下肢动脉成像在诊断糖尿病下肢动脉硬化闭塞症中的临床价值。方法对90例可疑下肢血管病变的Ⅱ型糖尿病患者进行64层螺旋CT血管造影检查,对所有扫描原始数据行容积再现(VR),最大密度投影(M IP),冠状、矢状面多平面重组(MPR)以及曲面重建(CPR)。结果64层螺旋CT下肢血管造影检查可以清晰显示自髂总至足背整个动脉系统病变的准确部位、范围及侧枝血管。90例患者中67例(77%)患者血管呈不同程度粥样硬化表现。其中轻或中度狭窄49例(56.3%),重度狭窄18例(20.7%),7例(8%)完全闭塞患者可见侧枝循环血管形成。结论64层螺旋CT下肢血管造影,对糖尿病下肢动脉硬化闭塞症的诊断和治疗具有重要价值。     

脊椎转移瘤增强减影MR成像

目的评估增强减影在脊椎转移瘤MR I中的应用价值。方法50例脊椎转移瘤病人进行MR I增强扫描,对比剂采用Gd-DTPA(0.1 mmol/kg),然后用T1W I增强后的图像与增强前的图像进行减影。通过对比噪声比(CNR)、信噪比(SNR)以及肿瘤边界清晰程度的比较,对MR I减影与否进行评估。结果MR I对比增强减影图像比传统的T1W I增强图像显示更清晰、更直观。所有脊椎转移瘤图像MR I减影的CNR和SNR比常规T1W I增强图像的CNR和SNR高。MR I减影CNR为155.05±24.73(x±SD),常规T1W I增强图像的CNR为11.11±14.26(t=35.65,Ρ<0.001)。MR I减影SNR为192.82±32.89(x±SD),常规T1W I增强图像的SNR为46.03±28.22(t=23.95,Ρ<0.001))。MR I对比增强减影图像比传统的T1W I增强图像能更好地显示脊椎转移瘤的边界和侵犯情况(2χ=29.34,Ρ<0.005)。结论MR I增强减影为探查和评估脊椎转移瘤提供了一个新的诊断方法。     

数字减影脑血管造影对原发性脑室出血的病因诊断价值

目的探讨DSA在原发性脑室出血(PIVH)原发病因检出中的应用价值。方法回顾性分析25例原发性脑室出血患者的DSA检查结果。结果25例患者中检出AVM8例,MoyaMoya病3例,颅内动脉瘤3例,海绵状血管瘤1例,造影阴性10例。结论DSA检查对甄别原发性脑室出血的病因具有重要的诊断意义,对有条件的PIVH病例均应行DSA检查以明确病因,作进一步病因治疗。