Measurement of vessel wall strain using cine phase contrast MRI

PURPOSE: To determine the feasibility of using magnetic resonance imaging (MRI) to non-invasively measure strain in the aortic wall. MATERIALS AND METHODS: Cine phase contrast MRI was used to measure the velocity of the aortic wall and calculate changes in circumferential strain over the cardiac cycle. A deformable vessel phantom was used for initial testing and in vitro validation. Ultrasonic sonomicrometer crystals were attached to the vessel wall and used as a gold standard. RESULTS: In the in vitro validation, MRI-calculated wall displacements were within 0.02 mm of the sonomicrometer measurements when maximal displacement was 0.28 mm. The measured maximum strain in vitro was 0.02. The in vivo results were on the same order as prior results using ultrasound echo-tracking. CONCLUSION: Results of in vivo studies and measurement of cyclic strain in human thoracic and abdominal aortas demonstrate the feasibility of the technique.     

西地那非对狗股骨头血流量的影响

目的　探索西地那非选择性增加股骨头血流量的可能性。方法　 a)狗 16只 ,随机分为 A、B两组 ,A组 10只用于经静脉用西地那非实验 ;B组 6只用于经髋关节外周动脉用西地那非实验。b)氢廓清技术用于定量测定股骨头血流量。结果　 a) A组 :高剂量组血流量从 (0 .16 89± 0 .0 2 80 ) m L· min- 1 · m L- 1 增加到 (0 .2 0 39± 0 .0 90 7) m L·min- 1 · m L- 1 ,差异不显著 ;中剂量组血流量从 (0 .15 4 1± 0 .0 4 2 1) m L· min- 1 · m L- 1 增加到 (0 .1783± 0 .0 84 7)m L·min- 1 ·m L- 1 ,无显著差异。b) B组 :低、中、高剂量用药后股骨头血流量增加 ,但仅高剂量用药后血流量 (0 .2 2 92± 0 .0 84 7) m L· min- 1· m L- 1与用药前的 (0 .1330± 0 .0 6 6 1) m L· min- 1· m L- 1比较有显著差异 ;血流量与药物剂量间存在回归关系 ,其回归方程为 :Y=4 .184 X 12 .933。结论　西地那非能增加狗股骨头血流量 ,为其治疗股骨头缺血性坏死疾病临床前评估提供了理论依据。     

Systematic and differential myelination of axon collaterals in the mammalian auditory brainstem

A brainstem circuit for encoding the spatial location of sounds involves neurons in the cochlear nucleus that project to medial superior olivary (MSO) neurons on both sides of the brain via a single bifurcating axon. Neurons in MSO act as coincidence detectors, responding optimally when signals from the two ears arrive within a few microseconds. To achieve this, transmission of signals along the contralateral collateral must be faster than transmission of the same signals along the ipsilateral collateral. We demonstrate that this is achieved by differential regulation of myelination and axon caliber along the ipsilateral and contralateral branches of single axons; ipsilateral axon branches have shorter internode lengths and smaller caliber than contralateral branches. The myelination difference is established prior to the onset of hearing. We conclude that this differential myelination and axon caliber requires local interactions between axon collaterals and surrounding oligodendrocytes on the two sides of the brainstem. GLIA 2016;64:487–494     

Nontarget Radiopaque Embolic Deposition during Prostatic Artery Embolization

This study evaluated detectable nontarget embolization (NTE) during prostatic artery embolization (PAE) and the safety and efficacy of using radiopaque particles in PAE. Ten patients aged >40 years with prostate glands of >50 mL and refractory lower urinary tract symptoms were analyzed. Unenhanced computed tomography scans at baseline and at 3 months after PAE, using 40–90-μm radiopaque spherical embolic beads, were compared to assess the NTE. Growth models evaluated changes from baseline to 3, 6, and 12 months in International Prostate Symptom Score (IPSS), peak urine flow rate (Qmax), quality of life (QoL), International Index of Erectile Function (IIEF), and postvoid residual (PVR). The IPSS, QoL, and Qmax improved at all time points (P < .05), with no trend in PVR or IIEF. Adverse events that occurred were minor. Radiographic NTE was seen in all patients, correlating at times with postprocedural symptoms (eg, rectal pain). Symptoms were not correlated with the NTE in some patients, whereas other patients remained asymptomatic despite NTE.     

RT-3DE定量评价心梗患者PCI术前后左室功能的变化

为探讨实时三维超声心动图(RT-3DE)定量评估心梗患者经皮冠状动脉介入治疗(PCI)术前后左室收缩功能及同步性参数的变化,选取100例接受PCI治疗的心肌梗死患者和100例正常对照组,应用RT-3DE技术对正常对照组和心梗患者PCI术前及术后1个月测量左心室收缩功能及同步性参数并进行比较。心梗患者PCI术前组左心室各功能参数值均劣于正常对照组,而术后1个月左心室各参数值均较术前明显改善。PCI术前、术后应用RT-3DE能够准确定位、定量反映左心室收缩功能及运动同步性,对心肌梗死的临床诊断及疗效评估具有重要价值。     

PSA三联疗法对缺血性脑卒中患者颈动脉结构及血流动力学的影响

目的 探讨普罗布考、阿托伐他汀、阿司匹林(PSA)三联疗法对缺血性脑卒中患者颈动脉结构及血流动力学的影响。方法 选择2016年1月至2017年3月收治的180例缺血性脑卒中患者为研究对象,采用随机数字表法分为PSA组、SA组、A组各60例,PSA组给予普罗布考、阿托伐他汀、阿司匹林联合治疗,SA组给予阿托伐他汀、阿司匹林治疗,A组给予阿司匹林治疗,随访6个月,比较两组血脂代谢、颈动脉结构与血流动力学指标。结果 PSA组、SA组总胆固醇(TC)、甘油三脂(TG)、低密度脂蛋白胆固醇(LDL-C)均明显低于A组,高密度脂蛋白胆固醇(HDL-C)明显高于A组(P＜0.05),PSA组TG、TC、LDL-C均明显低于SA组,HDL-C明显高于SA组(P＜0.05);PSA组、SA组颈动脉内-中膜厚度(IMT)、斑块面积明显小于A组,管腔直径明显大于A组(P＜0.05),PSA组IMT、斑块面积明显小于SA组,管腔直径明显大于SA组(P＜0.05);PSA组、SA组收缩期峰值血流速度(SV)、舒张期峰值血流速度(DV)均明显高于A组,阻力指数(RI)明显低于A组(P＜0.05),PSA组SV、DV明显低于PSA组,RI明显高于PSA组(P＜0.05)。结论 PSA三联疗法有助于调节缺血性脑卒中患者血脂代谢,改善颈动脉结构,提高颈动脉血流速度。     

原发性高血压患者脉搏波传导速度相关影响因素

【摘要】 目的 探讨原发性高血压患者脉搏波传导速度相关影响因素。方法 选取成都市晋阳社区卫生服务中心原发性高血压患者274例,其中男性125例,女性149例,年龄（6668±723）岁。采用日本全自动动脉硬化测定仪测量肱踝脉搏波传导速度（baPWV）。结果 在男性患者,baPWV与年龄（r=0331,P＜0001）、收缩压（r=0387, P＜0001）、空腹血糖（r=0188, P=0036）和中心动脉收缩压（r=0310, P＜0001）呈正相关;在女性患者中,baPWV与年龄（r=0416, P＜0001）、收缩压（r=0558, P＜0001）、舒张压（r=0184,P=0025）、空腹血糖（r=0201, P=0014）和中心动脉收缩压（r=0465, P＜0001）呈正相关。多元线性回归显示,年龄、收缩压、中心动脉收缩压、增强指数、踝臂指数是baPWV的独立影响因素。结论 在原发性高血压患者年龄、收缩压、中心动脉收缩压、增强指数和踝臂指数与baPWV密切相关。     

脉搏波传导速度及其在中医脉诊研究中的应用

论述脉搏波传导速度(PWV)的临床应用及在中医脉诊研究中的应用进展。PWV是脉搏波传导距离与传导时间的比值,作为评价动脉硬化的指标,当前临床应用以臂踝脉搏波传导速度(ba-PWV)和颈股脉搏波传导速度(cf-PWV)为主,主要用于心血管疾病、糖尿病、肾脏疾病等的诊断和风险评估,可较好地反映血管损伤程度、预测发病率及病死率。在中医脉诊研究中,PWV和脉图指标密切相关,两者联合可应用于中医脉象分类,亦有助于临床诊断和预防。     

HIFU消融不同T2WI信号子宫肌瘤疗效差异的组织声学性质

目的探讨HIFU消融T2WI低、等、高信号子宫肌瘤组织声衰减和声速的差异。方法收集经手术切除的子宫肌瘤标本45个。对患者术前行MR检查,根据T2WI信号强度将肌瘤分为低信号、等信号、高信号3种类型。采用插入取代式脉冲传输法测量肌瘤标本的声速和声衰减。结果 45个子宫肌瘤标本中,T2WI低信号肌瘤7个,等信号肌瘤9个,高信号肌瘤29个,其组织声速分别为(1 597.86±15.17)m/s、(1 586.70±10.83)m/s、(1 576.57±10.06)m/s,低、等信号肌瘤组织与高信号肌瘤组织比较差异均有统计学意义(P均0.05);声衰减分别为(4.03±1.34)dB/cm、(2.54±1.17)dB/cm、(1.04±0.66)dB/cm,低和等信号肌瘤组织与高信号肌瘤组织、低信号肌瘤组织与等信号肌瘤组织比较差异均有统计学意义(P均0.05)。结论 T2WI低、等、高信号子宫肌瘤组织声速、声衰减的差异可能是导致HIFU消融子宫肌瘤疗效差异的重要原因。