• 【孤立的半裂二尖瓣严重反流,导致从心血管磁共振成像诊断出左下肺静脉曲张。】 复制标题 收藏 收藏
    DOI:10.1007/s00246-012-0573-4 复制DOI
    作者列表:Teo LL,Hia CP,Ling LH,Quek SC
    BACKGROUND & AIMS: :Isolated cleft mitral valve (ICMV) is a rare entity not known to be related to pulmonary atresia with ventricular septal defect (PA-VSD). This report describes the use of cardiovascular magnetic resonance (CMR) imaging to diagnose ICMV in a patient with repaired PA-VSD who presented with incidental severe mitral regurgitation (MR) on follow-up echocardiography. An associated pulmonary varix secondary to the severe MR also was shown by CMR.
    背景与目标: :孤立的二尖瓣裂开(ICMV)是一种罕见病,未知与室间隔缺损的肺动脉闭锁(PA-VSD)相关。本报告介绍了在后续超声心动图检查中出现偶发性严重二尖瓣关闭不全(MR)的PA-VSD修复患者中,使用心血管磁共振(CMR)成像诊断ICMV的情况。 CMR还显示了继发于严重MR的相关肺静脉曲张。
  • 【用显微镜对蝴蝶翼秤进行光学散射成像。】 复制标题 收藏 收藏
    DOI:10.1098/rsfs.2017.0016 复制DOI
    作者列表:Fu J,Yoon BJ,Park JO,Srinivasarao M
    BACKGROUND & AIMS: :A new optical method is proposed to investigate the reflectance of structurally coloured objects, such as Morpho butterfly wing scales and cholesteric liquid crystals. Using a reflected-light microscope and a digital single-lens reflex (DSLR) camera, we have successfully measured the two-dimensional reflection pattern of individual wing scales of Morpho butterflies. We demonstrate that this method enables us to measure the bidirectional reflectance distribution function (BRDF). The scattering image observed in the back focal plane of the objective is projected onto the camera sensor by inserting a Bertrand lens in the optical path of the microscope. With monochromatic light illumination, we quantify the angle-dependent reflectance spectra from the wing scales of Morpho rhetenor by retrieving the raw signal from the digital camera sensor. We also demonstrate that the polarization-dependent reflection of individual wing scales is readily observed using this method, using the individual wing scales of Morpho cypris. In an effort to show the generality of the method, we used a chiral nematic fluid to illustrate the angle-dependent reflectance as seen by this method.
    背景与目标: :提出了一种新的光学方法来研究结构上有色物体的反射率,例如Morpho蝴蝶翼鳞和胆甾型液晶。使用反射光显微镜和数字单镜反光(DSLR)相机,我们已经成功地测量了Morpho蝴蝶单个机翼尺度的二维反射图案。我们证明了这种方法使我们能够测量双向反射率分布函数(BRDF)。在物镜的后焦平面上观察到的散射图像通过在显微镜的光路中插入一个Bertrand透镜而投射到相机传感器上。利用单色光照明,我们通过从数码相机传感器中检索原始信号,从Morpho rhetenor的机翼尺度上量化了与角度相关的反射光谱。我们还证明,使用这种方法,使用蓝蝶的单个机翼鳞片,很容易观察到单个机翼鳞片的偏振依赖性反射。为了说明该方法的一般性,我们使用手性向列液来说明该方法所见的角度依赖性反射率。
  • 【双膦酸盐诱发的颌骨坏死:对比增强MR成像,[18F]氟化物PET / CT和锥束CT成像对疾病范围的比较。】 复制标题 收藏 收藏
    DOI:10.3174/ajnr.A3355 复制DOI
    作者列表:Guggenberger R,Fischer DR,Metzler P,Andreisek G,Nanz D,Jacobsen C,Schmid DT
    BACKGROUND & AIMS: BACKGROUND AND PURPOSE:Imaging of bisphosphonate-induced osteonecrosis of the jaw is essential for surgical planning. We compared the extent of BONJ on contrast-enhanced MR imaging, [(18)F] fluoride PET/CT, and panoramic views derived from standard conebeam CT with clinical pre- and intraoperative examinations. MATERIALS AND METHODS:Between February 2011 and January 2012, ten subjects with written informed consent (9 women; mean, 69.6 years; range, 53-88 years) were included in this prospective ethics-board-approved study. Patients underwent CEMR imaging, [(18)F] fluoride PET/CT, and CBCT and were clinically examined pre- and intraoperatively. Surgery was performed, and BONJ was histologically confirmed in 9 patients. Location and extent of BONJ on different modalities/examinations were graphically compared (0 = no pathologic finding, 1 = smallest, 5 = largest extent of BONJ). Rank tests were used to assess overall and paired differences of ratings in 9 patients. A P value <.05 was considered statistically significant. RESULTS:Significant differences in BONJ extent among different modalities and examinations were found (P < .001). The highest median rank was seen in PET/CT (4 ± 1.12) and CEMR imaging (4 ± 1.01), followed by intraoperative examinations (3 ± 0.71), CBCT (2 ± 0.33), and preoperative examinations (1 ± 0). No significant differences were found between PET/CT and CEMR imaging (P = .23), except when comparing PET/CT to either CBCT, pre- and intraoperative examinations (all P < .05). Preoperative examinations showed significantly less extensive disease than all other modalities/examinations (all P < .05). CONCLUSIONS:[(18)F] fluoride PET/CT and CEMR imaging revealed more extensive involvement of BONJ compared with panoramic views from CBCT and clinical examinations.
    背景与目标: 背景与目的:双膦酸盐诱发的颌骨骨坏死的成像对于手术计划至关重要。我们将BONJ在对比增强MR成像,[(18)F]氟化物PET / CT和标准锥束CT的全景图与临床术前和术中检查之间进行了比较。
    材料与方法:在2011年2月至2012年1月之间,该前瞻性伦理委员会批准的研究包括十名获得书面知情同意的受试者(9名女性;平均69.6岁;范围53-88岁)。患者接受了CEMR成像,[(18)F]氟化物PET / CT和CBCT,并在术前和术中接受了临床检查。进行了手术,并在组织学上证实了9例患者的BONJ。以图形方式比较了BONJ在不同模态/检查中的位置和程度(0 =无病理发现,1 =最小,5 =最大程度的BONJ)。等级检验用于评估9位患者的总体和配对等级差异。 P值<.05被认为具有统计学意义。
    结果:在不同的方式和检查之间,BONJ范围存在显着差异(P <.001)。 PET / CT(4±1.12)和CEMR成像(4±1.01),手术中检查(3±0.71),CBCT(2±0.33)和术前检查(1±0)最高。除了将PET / CT与CBCT,术前和术中检查进行比较(所有P <.05)之外,PET / CT和CEMR成像之间没有发现显着差异(P = 0.23)。术前检查显示,与所有其他方式/检查相比,病灶明显更少(所有P <.05)。
    结论:[(18)F]氟化物PET / CT和CEMR成像显示,与CBCT和临床检查的全景图相比,BONJ的介入程度更大。
  • 【痴呆症磁共振成像中的认知和白质变化。】 复制标题 收藏 收藏
    DOI:10.1001/archneur.1990.00530040029015 复制DOI
    作者列表:Kertesz A,Polk M,Carr T
    BACKGROUND & AIMS: :In a prospective magnetic resonance imaging and cognitive study of 38 demented patients and 15 control subjects, 11 of 27 patients with Alzheimer's disease and 8 of 11 patients with vascular dementia had significant periventricular hyperintensities. Memory and language testing in the early investigation of dementia is useful to distinguish patients with or without periventricular hyperintensities on magnetic resonance imaging. Patients without periventricular hyperintensities are worse on memory and conceptualization tests than patients with periventricular hyperintensities, who tend to be worse on comprehension and attention tests. These differences in cognitive pattern are present between patients with different pathogenesis who are otherwise matched for dementia severity. Language and some nonverbal cognitive deficits correlate with the extent of cortical and ventricular atrophy in Alzheimer's disease.
    背景与目标: :在一项针对38名痴呆患者和15名对照受试者的前瞻性磁共振成像和认知研究中,27名阿尔茨海默氏病患者中的11名和11名血管性痴呆患者中的8名出现了明显的脑室高信号。痴呆症早期调查中的记忆和语言测试有助于区分磁共振成像中是否伴有脑室高信号的患者。没有脑室高信号的患者在记忆力和概念化测试方面比脑室高信号的患者在理解和注意力测试方面更差。这些认知模式上的差异存在于具有不同发病机制的患者之间,这些患者在其他方面因痴呆症的严重程度而匹配。语言和一些非语言认知缺陷与阿尔茨海默氏病的皮质和心室萎缩程度有关。
  • 【进行乳腺癌手术的妇女使用高级成像技术的趋势。】 复制标题 收藏 收藏
    DOI:10.1002/cncr.27838 复制DOI
    作者列表:Breslin TM,Banerjee M,Gust C,Birkmeyer NJ
    BACKGROUND & AIMS: BACKGROUND:Evidence-based guidelines recommend limited perioperative diagnostic imaging for new breast cancer diagnoses. For patients aged >65 years, conventional imaging use (mammography, plain radiographs, and ultrasound) has remained stable, whereas advanced imaging (computed tomography [CT], nuclear medicine scans [positron emission tomography/bone scans], and magnetic resonance imaging [MRI]) use has increased. In this study, the authors evaluated traditional and advanced imaging use among younger patients (aged ≤ 65 years) undergoing breast cancer surgery. METHODS:The MarketScan Commercial Claims and Encounters Research Database from 2005 through 2008 was analyzed to evaluate the use of conventional and advanced diagnostic imaging associated with surgery for ductal carcinoma in situ (DCIS) or stage I through III invasive breast cancer. RESULTS:The study cohort included 52,202 women (13% with DCIS and 87% with stage I-III breast cancer). The proportion of patients undergoing conventional imaging remained stable, whereas the average number of conventional imaging tests per patient increased from 4.21 tests in 2005 to 4.79 tests per patient in 2008 (P < .0001). For advanced imaging, the proportion of women who underwent imaging increased from 48.8% in 2005 to 68.8% in 2008 (P < .0001), as did the number of tests per patient (from 1.53 tests in 2005 to 1.98 tests in 2008; P < .0001). MRI examinations accounted for nearly all of the increase in advanced imaging. Patients who underwent MRI examinations received significantly more traditional imaging tests compared with to those who did not, indicating that these tests are additive and are not replacing traditional imaging. CONCLUSIONS:The current results demonstrate that the use of perioperative breast MRI has increased among women aged <65 years. Further study is indicated to determine whether the benefits of this procedure justify increased use.
    背景与目标: 背景:基于证据的指南建议对新的乳腺癌诊断进行有限的围手术期诊断成像。对于65岁以上的患者,传统的影像学检查(乳房X线照片,X线平片和超声检查)保持稳定,而高级影像学(计算机断层扫描[CT],核医学扫描[正电子发射断层扫描/骨扫描]和磁共振成像[ MRI])的使用有所增加。在这项研究中,作者评估了接受乳腺癌手术的年轻患者(≤65岁)的传统和高级成像使用情况。
    方法:对2005年至2008年的MarketScan商业索赔和遭遇研究数据库进行了分析,以评估与导管原位癌(DCIS)或I至III期浸润性乳腺癌手术相关的常规和高级诊断成像的使用。
    结果:该研究队列包括52,202名妇女(13%的DCIS患者和87%的I-III期乳腺癌患者)。接受常规影像学检查的患者比例保持稳定,而每名患者的常规影像学检查的平均次数从2005年的4.21次检查增加到2008年的4.79次检查(P <.0001)。对于高级影像学,接受影像学检查的女性比例从2005年的48.8%增加到2008年的68.8%(P <.0001),每位患者的检查次数也从2005年的1.53次增加到2008年的1.98次; P <.0001)。 MRI检查几乎占了高级影像学增长的全部。与未接受MRI检查的患者相比,接受过MRI检查的患者接受的传统成像检查要多得多,这表明这些检查是相加的,并且不能替代传统成像。
    结论:目前的结果表明,<65岁的女性围手术期乳房MRI的使用有所增加。指示需要进一步研究以确定该程序的益处是否可证明增加使用量是合理的。
  • 【通过荧光寿命成像显微镜观察细菌的代谢指纹图谱。】 复制标题 收藏 收藏
    DOI:10.1038/s41598-017-04032-w 复制DOI
    作者列表:Bhattacharjee A,Datta R,Gratton E,Hochbaum AI
    BACKGROUND & AIMS: :Bacterial populations exhibit a range of metabolic states influenced by their environment, intra- and interspecies interactions. The identification of bacterial metabolic states and transitions between them in their native environment promises to elucidate community behavior and stochastic processes, such as antibiotic resistance acquisition. In this work, we employ two-photon fluorescence lifetime imaging microscopy (FLIM) to create a metabolic fingerprint of individual bacteria and populations. FLIM of autofluorescent reduced nicotinamide adenine dinucleotide (phosphate), NAD(P)H, has been previously exploited for label-free metabolic imaging of mammalian cells. However, NAD(P)H FLIM has not been established as a metabolic proxy in bacteria. Applying the phasor approach, we create FLIM-phasor maps of Escherichia coli, Salmonella enterica serovar Typhimurium, Pseudomonas aeruginosa, Bacillus subtilis, and Staphylococcus epidermidis at the single cell and population levels. The bacterial phasor is sensitive to environmental conditions such as antibiotic exposure and growth phase, suggesting that observed shifts in the phasor are representative of metabolic changes within the cells. The FLIM-phasor approach represents a powerful, non-invasive imaging technique to study bacterial metabolism in situ and could provide unique insights into bacterial community behavior, pathology and antibiotic resistance with sub-cellular resolution.
    背景与目标: :细菌种群表现出一系列受其环境,种内和种间相互作用影响的代谢状态。细菌代谢状态及其在自然环境中之间的过渡的鉴定有望阐明社区行为和随机过程,例如获得抗生素抗药性。在这项工作中,我们采用双光子荧光寿命成像显微镜(FLIM)来创建单个细菌和种群的代谢指纹。自发荧光还原烟酰胺腺嘌呤二核苷酸(磷酸)的FLIM NAD(P)H先前已被用于哺乳动物细胞的无标记代谢成像。但是,NAD(P)H FLIM尚未被确定为细菌中的代谢替代物。应用相量方法,我们在单个细胞和群体水平上创建了大肠杆菌,肠炎沙门氏菌血清型鼠伤寒杆菌,铜绿假单胞菌,枯草芽孢杆菌和表皮葡萄球菌的FLIM相量图。细菌相量对环境条件敏感,例如抗生素暴露和生长期,这表明所观察到的相量变化代表细胞内代谢变化。 FLIM相量方法代表了一种强大的,非侵入性的成像技术,可用于原位研究细菌代谢,并且可以通过亚细胞分辨率为细菌群落行为,病理学和抗生素耐药性提供独特的见解。
  • 【脑扩散和T(2):持续高海拔缺氧期间急性高山病的MRI预测因子。】 复制标题 收藏 收藏
    DOI:10.1038/jcbfm.2012.184 复制DOI
    作者列表:Hunt JS Jr,Theilmann RJ,Smith ZM,Scadeng M,Dubowitz DJ
    BACKGROUND & AIMS: :Diffusion magnetic resonance imaging (MRI) provides a sensitive indicator of cerebral hypoxia. We investigated if apparent diffusion coefficient (ADC) and transverse relaxation (T(2)) predict symptoms of acute mountain sickness (AMS), or merely indicate the AMS phenotype irrespective of symptoms. Fourteen normal subjects were studied in two groups; unambiguous AMS and no-AMS at 3,800 m altitude (intermediate AMS scores were excluded). T(2) relaxation was estimated from a T(2) index of T(2)-weighted signal normalized by cerebrospinal fluid signal. Measurements were made in normoxia and repeated after 2 days sustained hypoxia (AMS group symptomatic and no-AMS group asymptomatic) and after 7 days hypoxia (both groups asymptomatic). Decreased ADC directly predicted AMS symptoms (P<0.05). Apparent diffusion coefficient increased in asymptomatic subjects, or as symptoms abated with acclimatization. This pattern was similar in basal ganglia, white matter, and gray matter. Corpus callosum behaved differently; restricted diffusion was absent (or rapidly reversed) in the splenium, and was sustained in the genu. In symptomatic subjects, T(2,index) decreased after 2 days hypoxia and further decreased after 7 days. In asymptomatic subjects, T(2,index) initially increased after 2 days, but decreased after 7 days. T(2,index) changes were not predictive of AMS symptoms. These findings indicate that restricted diffusion, an indicator of diminished cerebral energy status, directly predicts symptoms of AMS in humans at altitude.
    背景与目标: :扩散磁共振成像(MRI)提供了脑缺氧的敏感指标。我们调查了表观扩散系数(ADC)和横向弛豫(T(2))是否可预测急性高山病(AMS)的症状,还是仅指示AMS表型,而与症状无关。 14个正常受试者分为两组进行研究;在3,800 m的高度进行明确的AMS和无AMS(不包括中级AMS分数)。根据脑脊髓液信号归一化的T(2)加权信号的T(2)指数估算T(2)弛豫。在常氧状态下进行测量,并在持续缺氧2天(AMS组有症状和无AMS组无症状)和缺氧7天(两组无症状)后重复进行。 ADC降低直接预测AMS症状(P <0.05)。无症状受试者的表观弥散系数增加,或者随着适应环境的减轻症状逐渐减轻。这种模式在基底神经节,白质和灰质中相似。 call体表现不同。脾中不存在(或迅速逆转)受限制的扩散,并且在脾中持续存在。在有症状的受试者中,缺氧2天后T(2,index)下降,而在7天后T(2,index)进一步下降。在无症状受试者中,T(2,index)最初在2天后升高,但在7天后降低。 T(2,index)的变化不能预测AMS症状。这些发现表明,限制扩散是大脑能量状态减弱的指标,可直接预测高海拔地区人类的AMS症状。
  • 【评估用于荧光分子成像的辐射传递方程和扩散近似混合正解器。】 复制标题 收藏 收藏
    DOI:10.1117/1.JBO.17.12.126010 复制DOI
    作者列表:Gorpas D,Andersson-Engels S
    BACKGROUND & AIMS: :The solution of the forward problem in fluorescence molecular imaging strongly influences the successful convergence of the fluorophore reconstruction. The most common approach to meeting this problem has been to apply the diffusion approximation. However, this model is a first-order angular approximation of the radiative transfer equation, and thus is subject to some well-known limitations. This manuscript proposes a methodology that confronts these limitations by applying the radiative transfer equation in spatial regions in which the diffusion approximation gives decreased accuracy. The explicit integro differential equations that formulate this model were solved by applying the Galerkin finite element approximation. The required spatial discretization of the investigated domain was implemented through the Delaunay triangulation, while the azimuthal discretization scheme was used for the angular space. This model has been evaluated on two simulation geometries and the results were compared with results from an independent Monte Carlo method and the radiative transfer equation by calculating the absolute values of the relative errors between these models. The results show that the proposed forward solver can approximate the radiative transfer equation and the Monte Carlo method with better than 95% accuracy, while the accuracy of the diffusion approximation is approximately 10% lower.
    背景与目标: :荧光分子成像中前向问题的解决方案强烈影响荧光团重建的成功收敛。解决此问题的最常用方法是应用扩散近似。但是,该模型是辐射传递方程的一阶角近似,因此受到一些众所周知的限制。该手稿提出了一种通过在空间区域应用辐射传递方程来解决这些局限性的方法,其中扩散近似会降低精度。通过应用Galerkin有限元逼近法解决了表达该模型的显式积分微分方程。通过Delaunay三角剖分实现了所研究域的所需空间离散化,而方位角离散化方案则用于角空间。该模型已在两种模拟几何条件下进行了评估,并通过计算这些模型之间相对误差的绝对值,将结果与独立的蒙特卡洛方法和辐射传递方程的结果进行了比较。结果表明,所提出的前向求解器可以近似于95%的精度近似辐射传递方程和蒙特卡罗方法,而扩散近似的精度则低约10%。
  • 9 New horizons in breast imaging. 复制标题 收藏 收藏

    【乳房成像的新视野。】 复制标题 收藏 收藏
    DOI:10.1016/j.clon.2012.10.002 复制DOI
    作者列表:Kilburn-Toppin F,Barter SJ
    BACKGROUND & AIMS: :The imaging of breast cancer has undergone significant progression in recent years. A multimodality approach is often required, with ongoing developments in mammography, ultrasound, magnetic resonance and nuclear medicine all contributing to breast cancer imaging. Here we review the literature to assess how advances in well-established technologies, such as mammography, have brought added benefits both in terms of diagnostic and practical benefits, as well as allowing the application of derived technologies, such as tomosynthesis and contrast-enhanced mammography. We consider how these newer technologies may fit into clinical practice, both in terms of general population screening as well as use as problem solving tools in specific patient groups, and where the limitations for these may lie. We aim to highlight some of the promising advances in imaging that are still in earlier stages, such as magnetic resonance elastography, as well as reviewing techniques that are already becoming incorporated into clinical practice.
    背景与目标: :近年来,乳腺癌的影像学经历了重大进展。通常需要一种多模态方法,随着乳房X线照片,超声,磁共振和核医学的不断发展,所有这些都有助于乳腺癌的成像。在这里,我们回顾文献以评估诸如乳房X线照相术等成熟技术的进步如何在诊断和实际获益方面带来了额外的好处,以及如何允许诸如断层合成和对比增强的X线照相术等衍生技术的应用。我们从总体人群筛查以及在特定患者群体中用作问题解决工具的角度考虑这些更新技术如何适合临床实践,以及这些方法可能存在的局限性。我们的目标是突出显示仍处于早期阶段的一些有希望的成像进展,例如磁共振弹性成像以及已经纳入临床实践的检查技术。
  • 【非再灌注心肌梗死大鼠模型中的长期左心室重构:使用3T临床扫描仪进行的连续MR成像。】 复制标题 收藏 收藏
    DOI:10.1155/2012/504037 复制DOI
    作者列表:Saleh MG,Sharp SK,Alhamud A,Spottiswoode BS,van der Kouwe AJ,Davies NH,Franz T,Meintjes EM
    BACKGROUND & AIMS: :Purpose. To evaluate whether 3T clinical MRI with a small-animal coil and gradient-echo (GE) sequence could be used to characterize long-term left ventricular remodelling (LVR) following nonreperfused myocardial infarction (MI) using semi-automatic segmentation software (SASS) in a rat model. Materials and Methods. 5 healthy rats were used to validate left ventricular mass (LVM) measured by MRI with postmortem values. 5 sham and 7 infarcted rats were scanned at 2 and 4 weeks after surgery to allow for functional and structural analysis of the heart. Measurements included ejection fraction (EF), end-diastolic volume (EDV), end-systolic volume (ESV), and LVM. Changes in different regions of the heart were quantified using wall thickness analyses. Results. LVM validation in healthy rats demonstrated high correlation between MR and postmortem values. Functional assessment at 4 weeks after MI revealed considerable reduction in EF, increases in ESV, EDV, and LVM, and contractile dysfunction in infarcted and noninfarcted regions. Conclusion. Clinical 3T MRI with a small animal coil and GE sequence generated images in a rat heart with adequate signal-to-noise ratio (SNR) for successful semiautomatic segmentation to accurately and rapidly evaluate long-term LVR after MI.
    背景与目标: :目的。使用半自动分割软件(SASS)评估具有小动物线圈和梯度回波(GE)序列的3T临床MRI是否可用于表征非再灌注心肌梗死(MI)后的长期左心室重构(LVR)在大鼠模型中。材料和方法。使用5只健康大鼠通过验尸值验证通过MRI测量的左心室质量(LVM)。在手术后第2和第4周对5只假大鼠和7只梗塞的大鼠进行了扫描,以便对心脏进行功能和结构分析。测量包括射血分数(EF),舒张末期容积(EDV),收缩末期容积(ESV)和LVM。使用壁厚分析对心脏不同区域的变化进行定量。结果。在健康大鼠中的LVM验证表明MR和验尸值之间存在高度相关性。 MI后4周的功能评估显示,梗塞区和非梗塞区的EF明显降低,ESV,EDV和LVM升高,以及收缩功能障碍。结论。具有小动物线圈和GE序列的临床3T MRI在大鼠心脏中生成具有足够信噪比(SNR)的图像,可成功进行半自动分割,从而准确快速地评估MI后的长期LVR。
  • 【EPIC-Norfolk眼研究的正常参与者中水流出结构的光谱域光学相干断层扫描成像。】 复制标题 收藏 收藏
    DOI:10.1136/bjophthalmol-2012-302147 复制DOI
    作者列表:Day AC,Garway-Heath DF,Broadway DC,Jiang Y,Hayat S,Dalzell N,Khaw KT,Foster PJ
    BACKGROUND & AIMS: PURPOSE:To measure the dimensions of aqueous outflow structures and to investigate associations with intraocular pressure (IOP) and ocular biometry parameters in an older British population. METHOD:Fifty-two participants from the European Prospective Investigation of Cancer-Norfolk eye study underwent imaging using the Heidelberg Spectralis optical coherence tomographer with an anterior segment module. Pseudophakic participants and those known or suspected to have glaucoma were excluded, leaving 46 participants for analysis. Schwalbe's line (SL), scleral spur (SS), Schlemm's canal (SC) diameter and the trabecular meshwork cross-sectional area (TM cross-sectional area (CSA)) were identified and traced using ImageJ software. IOP was measured using the Ocular Response Analyser. Ocular biometry was measured by partial coherence interferometry. RESULTS:The mean (SD) subject age was 65.7 years (5.6). The SL and SS were identifiable in all nasal and temporal scans. The mean SL-SS distance was 800 μm (104) nasally and 808 μm (102) temporally. Repeatability of SS-SL, SS-SC, SC and TM CSA was good to excellent, and reproducibility fair to good. Nasal SL-SS distance was inversely associated with anterior chamber depth (ACD) (p=0.007, -116 μm per mm ACD, R(2)=0.18). Multiple linear regression showed nasal TM CSA was significantly associated with age and IOP (age: p=0.025, 0.007 mm(2) per decade of age; IOP: p=0.029, -0.0012 mm(2) per mm Hg, R(2)=0.23). CONCLUSIONS:Aqueous outflow structures can be measured by optical coherence tomography, and their dimensions vary significantly with ocular biometric characteristics and IOP. Further investigation is required to determine associations between outflow structure sizes in different populations and pathologies, including ocular hypertension and glaucoma.
    背景与目标: 目的:测量英国老年人口中房水流出结构的尺寸,并调查其与眼内压(IOP)和眼生物测定参数之间的关系。
    方法:来自欧洲-诺福克癌症前瞻性研究的52名参与者使用了带有前段模块的Heidelberg Spectralis光学相干断层扫描仪进行了成像。假晶状体参与者和已知或怀疑患有青光眼的参与者被排除在外,剩下46名参与者需要进行分析。使用ImageJ软件识别和追踪Schwalbe线(SL),巩膜骨刺(SS),Schlemm根管(SC)直径和小梁网截面积(TM截面积(CSA))。使用眼响应分析仪测量IOP。眼部生物测定法是通过部分相干干涉法测量的。
    结果:受试者的平均年龄为65.7岁(5.6)。在所有鼻腔和颞叶扫描中都可以识别出SL和SS。 SL-SS的平均距离鼻侧为800μm(104),颞侧为808μm(102)。 SS-SL,SS-SC,SC和TM CSA的可重复性从优到优,而重现性也不错。鼻SL-SS距离与前房深度(ACD)成反比(p = 0.007,-116μm/ mm ACD,R(2)= 0.18)。多元线性回归分析显示,鼻腔TM CSA与年龄和眼压显着相关(年龄:p = 0.025,每十岁年龄组0.007 mm(2); IOP:p = 0.029,-0.0012 mm(2)每毫米汞柱,R(2) )= 0.23)。
    结论:水流出结构可通过光学相干断层摄影术测量,其尺寸随眼生物特征和眼压而显着变化。需要进一步调查以确定不同人群和病理(包括高眼压和青光眼)的流出结构大小之间的关联。
  • 【后肢缺血的PET / SPECT成像:着重于血管生成和血流。】 复制标题 收藏 收藏
    DOI:10.1007/s10456-012-9319-4 复制DOI
    作者列表:Orbay H,Hong H,Zhang Y,Cai W
    BACKGROUND & AIMS: :Peripheral artery disease (PAD) is a result of the atherosclerotic narrowing of blood vessels to the extremities, and the subsequent tissue ischemia can lead to the up-regulation of angiogenic growth factors and formation of new vessels as a recovery mechanism. Such formation of new vessels can be evaluated with various non-invasive molecular imaging techniques, where serial images from the same subjects can be obtained to allow the documentation of disease progression and therapeutic response. The most commonly used animal model for preclinical studies of PAD is the murine hindlimb ischemia model, and a number of radiotracers have been investigated for positron emission tomography (PET) and single photon emission computed tomography (SPECT) imaging of PAD. In this review article, we summarize the PET/SPECT tracers that have been tested in the murine hindlimb ischemia model as well as those used clinically to assess the extremity blood flow.
    背景与目标: :周围动脉疾病(PAD)是动脉粥样硬化狭窄至四肢的结果,随后的组织缺血可导致血管生成生长因子的上调并形成新血管作为恢复机制。可以使用各种非侵入性分子成像技术来评估这种新血管的形成,其中可以获得来自相同受试者的系列图像,从而可以记录疾病的进展和治疗反应。用于PAD临床前研究的最常用动物模型是鼠后肢缺血模型,并且已经对PAD的正电子发射断层扫描(PET)和单光子发射计算机断层扫描(SPECT)成像研究了许多放射性示踪剂。在这篇综述文章中,我们总结了已经在鼠后肢缺血模型中测试过的PET / SPECT示踪剂,以及在临床上用于评估肢体血流的示踪剂。
  • 【在二氧化钒纳米束中通过表面配位效应稳定的金属样单斜晶相的成像。】 复制标题 收藏 收藏
    DOI:10.1038/ncomms15561 复制DOI
    作者列表:Li Z,Wu J,Hu Z,Lin Y,Chen Q,Guo Y,Liu Y,Zhao Y,Peng J,Chu W,Wu C,Xie Y
    BACKGROUND & AIMS: :In correlated systems, intermediate states usually appear transiently across phase transitions even at the femtosecond scale. It therefore remains an open question how to determine these intermediate states-a critical issue for understanding the origin of their correlated behaviour. Here we report a surface coordination route to successfully stabilize and directly image an intermediate state in the metal-insulator transition of vanadium dioxide. As a prototype metal-insulator transition material, we capture an unusual metal-like monoclinic phase at room temperature that has long been predicted. Coordinate bonding of L-ascorbic acid molecules with vanadium dioxide nanobeams induces charge-carrier density reorganization and stabilizes metallic monoclinic vanadium dioxide, unravelling orbital-selective Mott correlation for gap opening of the vanadium dioxide metal-insulator transition. Our study contributes to completing phase-evolution pathways in the metal-insulator transition process, and we anticipate that coordination chemistry may be a powerful tool for engineering properties of low-dimensional correlated solids.
    背景与目标: :在相关系统中,即使在飞秒级,中间状态通常也会在相变之间短暂出现。因此,如何确定这些中间状态仍然是一个悬而未决的问题,这是理解它们相关行为起源的关键问题。在这里,我们报告了一种表面配位路径,该路径可以成功稳定并直接成像二氧化钒的金属-绝缘体过渡过程中的中间状态。作为原型金属-绝缘体过渡材料,我们在室温下捕获了一种不寻常的类似金属的单斜晶相,该相已被长期预测。 L-抗坏血酸分子与二氧化钒纳米束的配位键诱导电荷载流子密度重组,并稳定金属单斜二氧化钒,从而消除了轨道选择性Mott相关性,从而消除了二氧化钒金属-绝缘子过渡带的缝隙。我们的研究有助于完成金属-绝缘体过渡过程中的相演化路径,并且我们预期配位化学可能是用于低维相关固体工程性质的有力工具。
  • 【使用第三谐波生成显微镜对骨骼多尺度孔隙度和界面进行无标记成像。】 复制标题 收藏 收藏
    DOI:10.1038/s41598-017-03548-5 复制DOI
    作者列表:Genthial R,Beaurepaire E,Schanne-Klein MC,Peyrin F,Farlay D,Olivier C,Bala Y,Boivin G,Vial JC,Débarre D,Gourrier A
    BACKGROUND & AIMS: :Interfaces provide the structural basis of essential bone functions. In the hierarchical structure of bone tissue, heterogeneities such as porosity or boundaries are found at scales ranging from nanometers to millimeters, all of which contributing to macroscopic properties. To date, however, the complexity or limitations of currently used imaging methods restrict our understanding of this functional integration. Here we address this issue using label-free third-harmonic generation (THG) microscopy. We find that the porous lacuno-canalicular network (LCN), revealing the geometry of osteocytes in the bone matrix, can be directly visualized in 3D with submicron precision over millimetric fields of view compatible with histology. THG also reveals interfaces delineating volumes formed at successive remodeling stages. Finally, we show that the structure of the LCN can be analyzed in relation with that of the extracellular matrix and larger-scale structures by simultaneously recording THG and second-harmonic generation (SHG) signals relating to the collagen organization.
    背景与目标: :接口提供基本的骨骼功能的结构基础。在骨组织的分层结构中,发现异质性(例如孔隙度或边界)的范围从纳米到毫米,所有这些都有助于宏观特性。然而,迄今为止,当前使用的成像方法的复杂性或局限性限制了我们对这种功能集成的理解。在这里,我们使用无标记的三次谐波(THG)显微镜来解决此问题。我们发现,多孔的腔管网络(LCN)揭示了骨基质中骨细胞的几何形状,可以在与组织学兼容的毫米视野中以亚微米精度直接以3D可视化。 THG还揭示了描述在连续重塑阶段形成的体积的界面。最后,我们表明,通过同时记录与胶原组织有关的THG和第二谐波产生(SHG)信号,可以分析LCN的结构与细胞外基质的结构和更大尺度的结构。
  • 【植物发育的实时成像:最新方法。】 复制标题 收藏 收藏
    DOI:10.1016/j.pbi.2012.10.006 复制DOI
    作者列表:Sappl PG,Heisler MG
    BACKGROUND & AIMS: :Development is a dynamic process occurring at the microscopic scale. The ability to see how it unfolds in detail is invaluable not only for helping us appreciate its full complexity but also to experimentally dissect its mechanisms. The sophistication of experimental approaches and imaging technologies has increased over the past decade at an astounding pace. In this review we highlight and discuss several studies that illustrate the latest advances in the application of live-imaging to dissect plant development.
    背景与目标: :发展是发生在微观尺度上的一个动态过程。了解它如何详细展现的能力非常宝贵,不仅有助于我们了解它的全部复杂性,而且还可以通过实验来剖析其机制。在过去的十年中,实验方法和成像技术的复杂性以惊人的速度增长。在这篇综述中,我们重点介绍并讨论了一些研究,这些研究说明了将实时成像技术应用于解剖植物发育的最新进展。

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