多层螺旋CT对老年复杂骨关节骨折的显像效果及分型诊断研究

目的分析16层螺旋CT(MSCT)对老年复杂骨关节骨折的显像效果及分型诊断价值。方法以我院2013年5月-2015年1月收治的70例复杂骨关节骨折患者为研究对象,均行数字X线(DR)检查及16-MSCT检查,其中MSCT扫描后行多平面(MPR)、三维表面(SSD)及容积(VR)重建,比较不同图像骨折线显示及骨折分型诊断。结果70例患者共215处骨折线,DR检出率77.2%,显著低于MSCT轴位图像、MPR、VR的97.7%、100.0%、90.7%,差异有统计学意义(P0.01)。骨折分型上DR误诊(包括漏诊)16例,其中胫骨平台骨折6例,脊柱骨折3例,髋臼骨折5例,踝关节骨折2例。结论相比DR,16-MSCT及其多种重建技术对老年复杂骨关节骨折的显像效果及分型诊断有明显优势。     

Volume-dependent compliance in ARDS: proposal of a new diagnostic concept

Objective: Adaptation of ventilator settings to the individual's respiratory system mechanics requires information about the pressure-volume relationship and the change of compliance which is dependent on inflated volume. Unfortunately, established methods of obtaining this information are invasive and time-consuming, and, therefore, not well suited for clinical routine. We propose a new standardized diagnostic concept based on the recently developed slice method. This multiple linear regression method (MLR) determines volume-dependent respiratory system compliance (C_SLICE) within the tidal volume (V_T) during ongoing mechanical ventilation. The impact of a ventilator strategy, recommended by a consensus conference, on the course of compliance within V_T was investigated in patients with the acute respiratory distress syndrome (ARDS) or acute lung injury (ALI).¶Design: Prospective observational study.¶Setting: Intensive care unit of a university hospital.¶Patients: 14 ARDS patients, 2 patients with ALI.¶Interventions: None.¶Measurements and results: After measurement of flow and airway pressure and calculation of tracheal pressure, C_SLICE was determined. The resulting course of C_SLICE within V_T was estimated using a mathematical algorithm. C_SLICE data were compared to those obtained by standard MLR. We found decreasing C_SLICE mainly in the upper part of V_T in all patients. In 7 patients, we found an additional increasing C_SLICE mainly in the lower part of V_T.¶Conclusions: C_SLICE was not constant in patients with ARDS/ALI whose lungs were ventilated according to consensus conference recommendations. The proposed diagnostic concept may serve as a new tool to obtain a standardized estimation of respiratory system compliance within V_T non-invasively without interfering with ongoing mechanical ventilation.     

Alterations of Glial Cell Function in Temporal Lobe Epilepsy

Summary: Purpose : Comparison of extracellular K⁺ regulation in sclerotic and nonsclerotic epileptic hippocampus.
Methods : Measurements of K⁺ signals with double-barreled K⁺-selective reference microelectrodes in area CA1 of slices from human and rat hippocampus, induction of increases in extracellular potassium concentration by repetitive alvear stimulation or iontophoresis, and block of inward-rectifying and background K⁺ channels in astrocytes by barium.
Results : In the CA1 pyramidal layer from normal rat hippocampus, barium augmented extracellular K⁺ accumulation induced by iontophoresis or antidromic stimulation in a dose-dependent manner. Similarly, barium augmented stimulusinduced K⁺ signals from nonsclerotic hippocampi (human mesial temporal lobe epilepsy). In contrast, barium failed to do so in sclerotic hippocampi (human mesial temporal lobe epilepsy, rat pilocarpine model).
Conclusions : Our findings suggest that in areas of reduced neuronal density (hippocampal sclerosis), glial cells adapt to permit rather large increases in extracellular potassium accumulation. Such increases might be involved in the transmission of activity through the sclerotic area.     

Behavioral deficits and cellular damage following developmental ethanol exposure in rats are attenuated by CP-101,606, an NMDAR antagonist with unique NR2B specificity

NMDAR-mediated excitotoxicity has been implicated in some of the impairments following fetal ethanol exposure. Previous studies suggest that both neuronal cell death and some of the behavioral deficits can be reduced by NMDAR antagonism during withdrawal, including antagonism of a subpopulation of receptors containing NR2B subunits. To further investigate NR2B involvement, we selected a compound, CP-101,606 (CP) which binds selectively to NR2B/2B stoichiometries, for both in vitro and in vivo analyses. For the in vitro study, hippocampal explants were exposed to ethanol for 10 days and then 24 h following removal of ethanol, cellular damage was quantified via propidium iodide fluorescence. In vitro ethanol withdrawal-associated neurotoxicity was prevented by CP (10 and 25 nM). In vivo ethanol exposure was administered on PNDs 1-7 with CP administered 21 h following cessation. Activity (PNDs 20-21), motor skills (PNDs 31-33), and maze navigation (PNDs 43-44) were all susceptible to ethanol insult; treatment with CP (15 mg/kg) rescued these deficits. Our findings show that CP-101,606, a drug that blocks the NR2B/2B receptor, can reduce some of the damaging effects of “3rd trimester” alcohol exposure in our rodent model. Further work is clearly warranted on the neuroprotective potential of this drug in the developing brain.     

Adeno-associated viral vector-mediated gene transduction in mesencephalic slice culture

Adeno-associated viral (AAV) vector is a non-pathogenic vehicle that is suitable for the delivery of foreign genes into non-dividing neuronal cells. This vector has been utilized for in vivo neurological research and in clinical trials of gene therapy for neurodegenerative disorders. Viral vector-mediated gene delivery has the limitation that progressive changes in cellular phenotype cannot be monitored in living animals. To visualize living neurons transduced with foreign genes in vitro, we used cultured mesencephalic tissue harboring living dopaminergic (DA) neurons and examined cellular tropism of serotype-1 and serotype-2 AAV vectors in a culture system. The viability of DA neurons was evaluated using transgenic mice carrying enhanced green fluorescent protein under the control of the rat tyrosine hydroxylase (TH) promoter, which enables the visualization of living DA cells in the substantia nigra. Apoptosis of a subset of neuronal cells was noted within one day of culture. After 7 days, the serotype-1 AAV vector had successfully delivered the foreign gene into neurons and astrocytes, and serotype-2 AAV vector was able to transduce TH-positive DA neurons efficiently. Our method should be useful for in vitro investigations of pathological changes in DA neurons following transduction with foreign genes.     

重建参数对CT肺结节容积测量的影响

背景与目的已有的研究证明:CT肺结节容积测量能够敏感反映结节容积的微小变化,在未定性肺结节的随访观察及良恶性鉴别方面具有重要应用前景。本研究旨在评估不同重建算法和层厚对CT肺结节容积测量的影响。方法对2009年12月-2011年8月在天津医科大学总医院行未定性肺结节CT随访研究的30例患者的CT图像进行后处理分析。共获取52个肺结节,应用3种不同的算法(骨密度算法、标准算法及肺算法)及层厚(0.625 mm、1.25 mm、2.5 mm)进行9次重建。由一位放射科医师应用肺结节容积分析软件进行容积测量。应用重复测量多元方差分析、相关分析及Bland-Altman法评价结节直径、算法、层厚对容积测量的影响。结果不同重建算法(F=13.6,P<0.001)、层厚(F=4.4,P=0.02)条件下测量所得的结节容积之间具有统计学差异。肺结节9次测量所得容积的变异系数和结节直径之间呈负相关(r=-0.814,P<0.001)。应用2.5mm层厚时,结节容积比1.25mm及0.625 mm层厚的一致性差,1.25 mm和0.625 mm层厚在采用骨算法时一致性最好。结论不同重建算法及层厚对肺结节容积测量有影响,尤其是直径较小的结节。在未定性肺结节尤其是肺小结节的随访过程中建议应用相同的重建参数。     

The influence of slice thickness on assessment of clavicle ossification in forensic age diagnostics

Computed tomography scans originally obtained to assess the ossification status of the medial clavicular epiphyses of 40 live subjects for forensic age estimation purposes were analysed. From the data acquired we reconstructed images with slice thicknesses of 1, 3, 5 and 7 mm, and based on the classification of stages by Schmeling et al. (Int J Legal Med 118:5–8, 2004), we determined the ossification stage for each reconstructed slice thickness, separately for both sides. Of the 80 clavicular epiphysial plates examined, seven displayed slice-thickness-dependent differences at certain ossification stages. In one case a slice thickness of 1 mm led to a different diagnosis of the ossification stage than a slice thickness of 3 mm, in three cases the diagnoses differed between the slice thicknesses of 3 and of 5 mm, and in another three cases, between 5 and 7 mm. We therefore conclude that for age estimation purposes, the slice thickness should be 1 mm to ensure maximum accuracy and diagnostic reliability.     

双源螺旋CT诊断冠脉易损斑块的应用价值

目的分析6 4层双源螺旋CT(DSCT)与冠脉造影(CAG)在冠脉易损斑块中的诊断价值。方法选取2013年7月-2015年7月因典型症状于我院就诊的63例冠心病患者作为研究对象,分别作64层双源螺旋CT检查与冠脉造影检查,评估64层双源螺旋CT在冠脉易损斑块中的诊断价值。结果 DSCT检出冠脉狭窄病变141处,CAG检出156处,两者检出冠脉病变节段数对比差异无统计学意义(P0.05),以CAG作为标准,DSCT检测敏感度为93.6%,特异性为94.3%,阴性预测值为97.0%,阳性预测值为84.6%;DSCT检出稳定性心绞痛患者软斑块、纤维斑块、硬斑块分别占16.7%、26.7%、56.7%,其中软斑块所占比例显著低于不稳定型心绞痛组,硬斑块比例则显著高于不稳定型心绞痛组(P0.05);DSCT共检出156处冠脉斑块病变,与CAG检出率无差异,其中轻度、中度、重度狭窄分别为21处、66处与57处,轻度、中度狭窄均以软斑块为主,重度狭窄以硬斑块为主,重度组硬斑块所占比例显著高于轻中度狭窄组(P0.05)。结论DSCT对冠心病患者冠脉狭窄程度、斑块性质的诊断均有较高的准确性,与CAG有较高的符合度,对指导冠心病相关心血管并发症的防治有积极的价值。     

不同心率对于640层螺旋CT冠状动脉成像质量及相关辐射剂量的影响

目的探讨不同心率在640层螺旋CT冠状动脉CTCA中对血管图像质量的影响以及辐射剂量变化。方法选取91例患者,男性51例,女性40例,平均年龄58岁。分成三组,A组30例,心率≤65次/分;B组30例,65次/分心率≤80次/分;C组31例,心率80次/分。扫描完成后选取最佳时相进行容积再现(VR)、最大密度投影(MIP)、多平面重建(MPR)及曲面重建(CPR)进行血管重建,根据4分法对血管图像质量分级并进行统计学分析,记录各组的辐射剂量程度乘积(DLP)。结果三组的血管图像质量在可评价比例及优良率无统计学意义,心率与血管图像质量等级呈负相关。A组DLP为(3.37±2.12)m Gy.cm,B组为(4.78±1.92)m Gy.cm,C组为(6.11±2.79)m Gy.cm,三组的辐射剂量有差异,经检验,有统计学意义,心率与辐射剂量呈正相关。结论 640层螺旋CT冠状动脉CTCA在高心率患者能较好的显示图像,同时辐射剂量也增加,应该在情况允许的条件下尽可能降低心率至65次/分以下,在获得优良血管图像质量的同时降低辐射剂量,有利于冠状动脉CTCA的可持续发展,以便让更多患者从中获益。     

64排CT在创伤性颅脑损伤诊断中的临床价值分析

目的研究64排CT在创伤性颅脑损伤的诊断价值、预后判断方面的意义。方法回顾性分析200例颅脑损伤患者,入院时行CT检查,如果结果为阴性,则在1d内复查CT,再次阴性者第2-3d内第三次检查,总结患者CT影像特点,根据CT影像特点计分并分为轻、中、重三型,分析不同损伤分型对预后的影响。结果颅脑损伤CT影像表现多种多样,存在硬膜外和硬膜下出血、颅骨骨折、蛛网膜下腔出血等,轻、中、重三型的死亡、重残、中残人数差异较大,具有统计学意义,P0.05;经三次检查共有198例患者阳性,特异度均达100%,刚入院时灵敏度为69.5%(139/200),1d内73.9%(51/69),2-3d为100%(18/18)。结论 CT对诊断颅脑损伤优势明显,灵敏度和特异度均较高,CT结果与患者预后紧密相关,可指导临床治疗,因此颅脑损伤首选CT。