肺通气氧功能成像对区域性肺通气信息的实验观察

目的探讨应用肺通气联合肺灌注磁共振功能成像对犬肺栓塞的诊断作用. 方法选择 4只犬于数字减影血管造影( digital substraction angiography, DSA)下经导管将吸收性明胶海绵条注入左下肺动脉后复制肺栓塞动物模型.犬于栓塞前分别吸入室内空气( 21% O2)和高浓度氧( 99.5% O2)及栓塞后再次吸入高浓度氧行肺通气 MRI扫描,分别测出左下肺信号强度,观察反映肺通气的信号强度的变化.犬于栓塞前和栓塞后分别行肺灌注 MRI扫描观察左下肺的灌注情况. 结果肺通气 MRI扫描时,左下肺栓塞前吸入 99.5% O2后较吸入室内空气时的肺实质信号强度明显增加,栓塞后吸入 99.5% O2肺实质信号强度亦明显增加,同未栓塞的右下肺相同步骤时的信号强度增加值相比无显著性差异 (t=3.685, P >0.05),说明左下肺栓塞后肺通气未受影响.肺灌注 MRI扫描时注入造影剂后,右下肺未栓塞区的信号强度迅速上升,于第 6.8秒达灌注峰值期,而左下肺栓塞区的时间信号强度曲线低平,始终未出现明显的灌注峰值期. 结论 MRI肺通气氧功能成像联合灌注成像为肺栓塞的诊断提供了一种新的诊断手段,对肺栓塞的诊断是可行的也是有益的.     

俯卧位通气加肺复张对急性呼吸窘迫综合征的作用

目的 评价俯卧位通气(PPV)联合肺复张(RM)对急性呼吸窘迫综合征(ARDS)犬的肺保护作用及机制.方法 经股静脉快速注入油酸建立犬ARDS模型,容积控制通气,在小潮气量(VT,10 ml/kg)+高呼气末正压(PEEP,16 cm H2O,1 cm H2O=0.098 kPa)通气基础上,按随机数字表法分为仰卧位组、俯卧位组、仰卧+RM组、俯卧+RM组,每组6只.测定通气后0.5、2和4 h血清细胞因子.4 h后经股动脉放血处死动物,开胸取肺;取左肺组织制备匀浆,测定细胞因子;取右肺测定湿/干重(W/D)比值及制备病理切片,行病理评分.结果 ①通气4 h时仰卧+RM组血清白细胞介素-8(IL-8)浓度明显高于其他3组(P均<0.05),且仰卧+RM组血清肿瘤坏死因子-α(TNF-α)浓度明显高于俯卧位组及俯卧+RM组(P均<0.05).②俯卧位组及俯卧+RM组背侧肺组织匀浆中IL-8浓度明显低于仰卧位组(P均<0.05),TNF-α浓度明显低于仰卧+RM组(P均<0.05).③俯卧位组、俯卧+RM组右肺W/D比值明显低于仰卧位组及仰卧+RM组(P均<0.05).④俯卧位组及俯卧+RM组背侧病理评分显著低于仰卧位组及仰卧+RM组(P均<0.05).结论 在犬ARDS模型中,予以小VT+PEEP的肺保护性通气时,在俯卧位实施RM可以减轻肺损伤.     

急性呼吸窘迫综合征在肺灌洗后行俯卧位通气的疗效观察

目的观察急性呼吸窘迫综合征患者在肺灌洗后行俯卧位通气治疗对氧合、肺力学的影响及作用。方法20例急性呼吸窘迫综合征患者在肺灌洗后行俯卧位通气治疗,分别监测治疗前、治疗后的氧分压、气道峰压、炎症介质的变化,观察治疗前后患者胸部CT影像学的变化。结果经过肺灌洗和俯卧位通气2 h后氧分压明显升高、气道峰压显著下降,俯卧位通气1 d后胸部CT检查显示肺实变区部分消失,炎症介质检验显示明显下降。结论肺灌洗后行俯卧位通气可改善早期急性呼吸窘迫综合征患者的氧合,有效改善肺部炎症。     

俯卧位通气联合肺保护性通气策略对急性呼吸窘迫综合征病人病死率影响的累积Meta分析

目的:应用累积Meta分析的方法评价俯卧位通气(prone positioning ventilation, PPV)联合肺保护性通气策略对急性呼吸窘迫综合征(ARDS)病人病死率的影响。方法:计算机检索PubMed、Web ofScience、the Cochrane Library、中国知网、维普数据库、万方数据库所有公开发表的关于PPV联合肺保护性通气策略应用于ARDS病人的随机对照试验,检索时限为建库至2022年7月31日。通过纳入文献的参考文献进行引证检索。采用StataSE 12.0软件对不同时间段纳入文献中病人的病死率进行累积Meta分析,采用试验序贯分析法估算累积Meta分析样本量评价研究结果的真实性,采用Beggs法对纳入研究进行发表偏倚检验。结果:共纳入4篇英文文献,涉及病人984例,其中试验组502例,对照组482例。累积Meta分析结果显示,PPV联合肺保护性通气策略能降低ARDS病人病死率,差异有统计学意义[OR=0.60,95%CI(0.46,0.78),P<0.001]。试验序贯分析结果显示,累积Meta分析样本量虽未达到估算样本量,但已获得较肯定结...     

不同自主呼吸训练方法对区域性肺通气影响的对比研究

摘要目的：利用生物电阻抗成像（EIT）技术探究不同自主呼吸训练方法对区域性肺通气的影响, 以期为慢性阻塞性肺疾病（COPD）患者在训练标准及方法选取上提供行之有效的康复指导方案。方法：共纳入28名健康志愿者,取舒适站立位并进行：①平静呼吸;②腹式呼吸;③缩唇呼吸;④腹式缩唇呼吸,每位被试的四种呼吸方式随机决定,整个过程中连续记录胸部EIT;分别对比四种呼吸方式期间的潮气量（TV）、呼气末肺阻抗（EELI）、通气中心（center of ventilation, CoV）、不均一指数（GI）、区域通气延迟（RVD）。结果：较平静呼吸,腹式呼吸、缩唇呼吸及腹式缩唇呼吸三种呼吸训练方法期间的TV明显增大（P＜0.05）; EELI明显降低（P＜0.05）;CoV明显减小（P＜0.05,腹侧通气增多）;腹式呼吸和腹式缩唇呼吸的GI明显减小（P＜0.05,通气更均匀）;缩唇呼吸和腹式缩唇呼吸RVD明显增加（P＜0.05）。结论：腹式呼吸、缩唇呼吸、腹式缩唇呼三种呼吸训练方法均能有效增加肺通气量,减少肺功能残气量,但三种呼吸训练方法对肺通气的影响各不相同：缩唇呼吸通气向腹侧移动更显著（COV更小）,区域通气延迟更显著（RVD更大）,而腹式呼吸可改善通气均匀性（GI更小）。因此,从区域性肺通气的角度,建议COPD患者在进行呼吸训练时应腹式呼吸与缩唇呼吸独立交替进行,以达到更好的呼吸训练效果。     

基于灰度的二维/三维图像配准方法及其在骨科导航手术中的实现

目的随着基于医学图像导航的手术对三维信息需求的加强,建立二维/三维的医学图像配准算法,在二维规划的基础上引入三维信息。方法首先,将获取的骨盆图像体数据集通过投影得到DRR图像,将获取的X线图像进行校正;然后,利用灰度相似性测度配准DRR图像和无失真X线图像。结果在初始位置相对坐标位移<20mm,角度<5°时配准精度小于1.47%,取得良好的配准结果。结论本文提出的基于灰度计算的配准技术能够实现术中二维医学图像与术前三维医学图像的配准,实现术中二维/三维手术规划相结合。     

密闭式吸痰联合肺复张在急性呼吸窘迫综合征俯卧位机械通气患者的应用观察

目的观察密闭气管内吸痰后联合肺复张技术在急性呼吸窘迫综合征(ARDS)俯卧位机械通气患者的应用效果。方法选取我院2017年1月-2019年12月RICU收治的各种原因导致ARDS行俯卧机械通气患者64例,将2017年1月-2018年6月的32例患者设为对照组,2018年7月-2019年12月的32例患者设为观察组,两组患者都采用间断俯卧位机械通气,观察组每次密闭气管内吸痰后立即进行一次小潮气量和高呼吸末正压肺复张,对照组常规进行密闭吸痰,观察两组患者密闭吸痰和密闭气管内吸痰后联合肺复张前、后氧合指数P(O 2)/FiO 2和氧分压P(O 2)的变化情况,血流动力学指标的变化和不良事件的发生情况。结果两组患者在吸痰前P(O 2)/FiO 2和PaO 2相比较,差异无统计学意义(P>0.05),观察组在执行密闭吸痰后联合肺复张操作后第3天、第6天P(O 2)/FiO 2和P(O 2)均高于对照组,差异有统计学意义(P<0.05)。两组患者在血流动力学指标(HR、CVP、MAP)比较无统计学意义(P>0.05),且无并发症发生。结论密闭吸痰后应用肺复张技术,明显改善了ARDS俯卧机械通气患者的氧合状态,且血流动力学指标稳定,无并发症发生,密闭吸痰联合肺复张技术在ARDS俯卧机械通气的患者应用中安全有效。     

基于4E模式的ICU早期康复方案在机械通气患者中的应用

目的:分析基于4E模式的ICU早期康复方案在机械通气患者中的应用效果。方法:采用便利抽样法,选取某医院2个ICU病区收治的74例患者为研究对象,ICU一区患者为实验组(n=38),ICU二区患者为对照组(n=36)。对照组接受常规康复护理,实验组接受基于4E模式的ICU早期康复方案。结果:两组患者在ICU谵妄发生率、谵妄持续时间、医学研究理事会肌力评分、ICU获得性衰弱(ICU-AW)发生率、机械通气时间、ICU住院时间、总住院时间等方面差异均有统计学意义(P<0.05)。在实施过程中,实验组患者未发生早期康复相关的严重不良事件。结论:对机械通气患者实施基于4E模式的ICU早期康复方案安全可行且有效,可改善患者肌力,降低ICU-AW及ICU谵妄发生率,缩短ICU谵妄持续时间、机械通气时间、ICU住院时间与总住院时间。     

俯卧位通气对高海拔地区肺复张治疗无效急性呼吸窘迫综合征患者氧合的影响

目的 探讨俯卧位通气对高海拔地区肺复张术(RM)治疗无效急性呼吸窘迫综合征(ARDS)患者的治疗作用.方法 从海拔2260m的地区医院筛选RM治疗无效的41例ARDS患者[平均氧合指数( PaO2/FiO2)较RM前升高＜20％视为RM无效],依不同病因分为肺内源性ARDS组(ARDSp组)和肺外源性ARDS组(ARDSexp组),每组再按信封法随机分为俯卧位组和仰卧位组,即ARDSp俯卧位组(11例)、ARDSp仰卧位组(9例)、ARDSexp俯卧位组(10例)、ARDSexp仰卧位组(11例).在通气前及通气1、2、3、4h监测动脉血氧分压( PaO2)、PaO2/FiO2、静态顺应性(Cst)、气道阻力(Raw)的变化.结果 通气lh时,ARDSexp俯卧位组PaO2/FiO2( mm Hg,l mm Hg=0.133 kPa)即较通气前显著升高(157.4±40.6比129.3±48.7,P＜0.05),并随通气时间延长呈持续增高趋势,4h达峰值(219.1 ±41.1);且ARDSexp俯卧位组通气3h内PaO2/FiO2较其他3组显著增高,另3组间则差异无统计学意义.ARDSp俯卧位组、ARDSexp俯卧位组通气4h时PaO2/FiO2均较相应仰卧位组显著增高(208.8±39.7比127.4±47.1,219.1±41.1比124.9±50.8,均P＜0.05).4组通气前后Cst无显著改变,各组间差异也无统计学意义.ARDSp俯卧位组通气4h时Raw(cmH2O·L-1·s-1)较通气前显著降低(6.8±1.7比10.7±1.8,P＜0.05),且明显低于其他3组;其他3组各时间点Raw组内及组间比较差异均无统计学意义.结论 俯卧位通气作为ARDS机械通气重要策略之一,可以改善RM无效高原ARDS患者的氧合,为抢救患者赢得宝贵的时间.     

Detection of severe pulmonary hypertension based on computed tomography pulmonary angiography

The International Journal of Cardiovascular Imaging - Pulmonary hypertension (PH) is often diagnosed late in the disease course. As many patients may undergo computed tomography pulmonary...     

Never say never: Identification of acute pulmonary embolism on non-contrast computed tomography imaging

Acute undifferentiated illness remains a critical challenge for the emergency physician. The diagnostic evaluation and treatment decisions on such severely ill patients often needs to be made in an expedited fashion. Situations occur wherein the ideal or recommended workup is not always feasible due to time or patient specific factors. We present two cases of patients with undifferentiated acute illness who had undergone non-contrast CT (computed tomography) scanning and subsequently had central pulmonary embolism identified upon careful review of their CT studies.     

Noninvasive cardiac imaging with computed tomography

Despite major improvements in the treatment of heart disease, it remains a major source of morbidity and mortality on a global scale. Currently, invasive coronary angiography remains the gold standard for identification of obstructive coronary artery disease. However, recent advances in computerized tomographic (CT) techniques of the heart allow for accurate, noninvasive characterization of atherosclerotic coronary disease and other cardiac abnormalities. The calculation of coronary artery calcium scores with electron beam CT has largely been supplanted by high-resolution CT angiography using multislice detectors (MSCT) which can provide detailed multidimensional visualization of cardiac structures. Although evaluation of obstructive coronary disease is the primary use of MSCT, its use in identifying congenital defects, planning thoracic procedures and characterizing cardiac function continues to grow. Accordingly, appropriate incorporation of MSCT/CT angiography into clinical practice continues to be defined. Several limitations to MSCT remain which reduce its accuracy, such as in patients with arrhythmia and in patients with either coronary stents or heavily calcified coronaries. Despite its current limitations, MSCT remains a rapidly advancing field and an increasingly valuable tool for the noninvasive evaluation of cardiac pathology.     

Quantitative analysis of metacarpophalangeal joints during active flexion using four-dimensional computed tomography

BackgroundThe metacarpophalangeal joint has a unique morphology with a high degree of freedom. However, few studies have analyzed the kinematics of fingers owing to the rapid movement of the small bones involved. The in-vivo kinematics of metacarpophalangeal joints were analyzed by four-dimensional computed tomography (4DCT) and associated with its morphology.MethodsThe flexion motion of the fingers of bilateral hands in 10 volunteers were examined using 4DCT. Iterative surfaces were registered to trace the surface of the proximal phalanges with respect to metacarpals. Rotation angles were calculated using Euler/Cardan angles.FindingsIn the index finger, the proximal phalange supinated to a maximum flexion of 40° and then pronated, and its range of rotation was larger than the previous reports. In the other fingers, the proximal phalanges continued to supinate during flexion. The helical axis of the proximal phalange passed a point extremely close to the center point of bilateral condyles, and it moved toward the proximal and palmar directions until the middle stage of flexion and toward the proximal and dorsal directions during the late stage of flexion. The translation of the rotation axis was larger in the ring and little fingers.InterpretationThe rotation in the index finger was larger than previously reported. The helical axes moved in the dorsal direction and proximally during the latter phase of the flexion. These results can be employed to better understand the causes of implant failure of the metacarpophalangeal joints.     

X-ray luminescence computed tomography imaging based on X-ray distribution model and adaptively split Bregman method

X-ray luminescence computed tomography (XLCT) has become a promising imaging technology for biological application based on phosphor nanoparticles. There are mainly three kinds of XLCT imaging systems: pencil beam XLCT, narrow beam XLCT and cone beam XLCT. Narrow beam XLCT can be regarded as a balance between the pencil beam mode and the cone-beam mode in terms of imaging efficiency and image quality. The collimated X-ray beams are assumed to be parallel ones in the traditional narrow beam XLCT. However, we observe that the cone beam X-rays are collimated into X-ray beams with fan-shaped broadening instead of parallel ones in our prototype narrow beam XLCT. Hence we incorporate the distribution of the X-ray beams in the physical model and collected the optical data from only two perpendicular directions to further speed up the scanning time. Meanwhile we propose a depth related adaptive regularized split Bregman (DARSB) method in reconstruction. The simulation experiments show that the proposed physical model and method can achieve better results in the location error, dice coefficient, mean square error and the intensity error than the traditional split Bregman method and validate the feasibility of method. The phantom experiment can obtain the location error less than 1.1 mm and validate that the incorporation of fan-shaped X-ray beams in our model can achieve better results than the parallel X-rays.OCIS codes: (110.3010) Image reconstruction techniques, (340.7440) X-ray imaging     

Multidetector-row computed tomography for noninvasive coronary imaging

Computed tomography (CT) permits cross-sectional imaging of the heart. Temporal and spatial resolutions of the technique have been insufficient to cover the heart without motion artefacts until the recent advent of multidetector systems with more than 16 detector rows. The modality is now suited for noninvasive imaging of the coronary arteries, producing detailed morphologic images of the entire coronary tree with upto 0.4 mm of spatial resolution, within a single short breath-hold duration. CT imaging goes beyond the delineation of the coronary lumen as provided by selective invasive angiography; the plaque burden of the coronary artery wall can be visualized directly, utilizing soft-tissue contrast and a high sensitivity even for the small calcifications that are present in hard plaque formations. Therefore, CT combines elements of catheterization angiography for lumen imaging and of intravascular ultrasound imaging for coronary wall imaging. However current CT technology is not yet able to compete with the temporal or spatial resolution of catheterization angiography nor does it provide the detailed spatial or contrast resolution of intravascular ultrasound imaging. At present, its use is therefore restricted to complementing the invasive modalities in appropriate indications. Although CT entails significantly less risk than the invasive procedures, the risks of radiation dose exposure and contrast agent application are not negligible. In the foreseeable future, if the current rate of technological advancement continues, CT may replace the invasive modalities in routine care for diagnostic purposes.     

Three-dimensional cerebral vasculature of the CBA mouse brain: a magnetic resonance imaging and micro computed tomography study

Studies of mouse cerebral vasculature to date have focused on the circle of Willis without examining the morphological distribution of blood vessels through the rest of the brain. Since mouse models are frequently used in brain-related studies, there is a need for a comprehensive cerebral vasculature atlas for the mouse with an emphasis on the location of vessels with respect to neuroanatomical structures, the watershed regions associated with specific arteries, as well as a consistent nomenclature of the cerebral vessels. This article describes such an atlas, based on a combination of magnetic resonance and computed tomography technology to yield high-resolution volumetric and vasculature data on CBA mouse. This three-dimensional vasculature dataset provides an anatomical resource for future mouse studies.     

多层CT显示肺结节细分叶征及其对孤立性肺结节的诊断价值

目的:使用多层CT(MDCT)显示肺结节的细分叶征并探讨其在孤立性肺结节(SPN)诊断中的价值。方法:本组共收集CT横断面SPN最大直径≤30mm的病例62例,其中周围型肺癌32例,良性SPN30例,采用四层CT扫描仪对每个病例均完成容积显示(VR)处理并使用自主调节的模式进行显示。结果:肺癌的分叶征出现率为93.8%(30/32),明显高于非肺癌结节(良性SPN)[46.7%(14/30)],(χ2=16.660,P=0.001)。7例(21.9%)肺癌结节出现典型的细分叶征,其中肺泡癌4例,腺癌3例。无一例良性SPN出现细分叶征。典型的细分叶征表现为VR上肺结节表面有5个以上的微小半球形突起(直径不超过5mm),常规CT横断面不能显示该特征。结论:MDCT的VR图像可以很好地显示肺癌结节的细分叶征,该征可能是周围型肺癌的定性诊断特征。