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91.
目的 研究三维可视化(3DV)、吲哚菁绿荧光融合影像(FIGFI)、虚拟现实(VR)技术等多模影像技术在解剖性肝切除手术导航的应用价值。方法 选择2016年1月至2018年6月间南方医科大学珠江医院肝胆外科64例肝脏肿瘤病人临床资料。采用MI-3DVS对薄层CT图像数据进行个体化的肝脏、肝内脉管和肿瘤三维重建,并将三维重建模型导入VR开发引擎中转化为VR模型,指导术前规划和决策;术中使用荧光成像仪对肝脏、肿瘤进行侦测,并联合3DV和VR技术导航肝切除手术。结果 MI-3DVS三维重建的64例病人肝脏、肿瘤及肝内脉管等结构清晰;通过头戴式显示器及安装了捕捉手和手指运动的传感器的操纵手柄融入一个 3D-VR环境,更立体直观地显示前期3DV模型的沉浸感、空间感和立体感;FIGFI可进行肿瘤边界界定、肝切缘的界定、微小肝癌和肝切缘残留病灶的侦测。64例病人中,肝左外叶切除4例,肝左叶切除16例,肝右前叶切除5例,肝右后叶切除5例,肝右叶切除17例,肝中叶切除术5例,肝段切除11例(5段3例、6段6例、7段1例、8段1例),尾状叶切除1例。实际手术过程与术前手术规划一致。术后均未出现腹腔出血、胆漏、肝功能衰竭等严重并发症,围手术期无死亡病例。结论 多模影像技术在术前精确影像评估和术中导航解剖性、功能性、根治性肝切除手术具有重要应用价值。 相似文献
92.
Early diffusion-weighted imaging and outcome prediction of comatose survivors after suicidal hanging
Dong Won Choi Suk Woo Lee Seong-Hae Jeong Jung Soo Park Hoon Kim 《The American journal of emergency medicine》2019,37(1):5-11
Purpose
Early outcome prediction after suicidal hanging is challenging in comatose survivors. We analysed the early patterns of brain diffusion-weighted magnetic resonance imaging (DWI) abnormalities in comatose survivors after suicidal hanging.Methods
After suicidal hanging, 18 comatose survivors were prospectively evaluated from January 2013 to December 2016. DWI was performed within 3?h after hanging in comatose survivors. We evaluated Utstein style variables and analysed abnormal spatial profile of signal intensity on DWI, brain apparent diffusion coefficient (ADC) values, and qualitative DWI scores to predict neurological outcomes.Results
All hanging associated cardiac arrest (CA) patients demonstrated bad neurological outcomes; 80% of non-CA comatose patients experienced good neurological outcomes. In hanging survivors with CA, cortical grey matter structures and deep grey nuclei exhibited profound ADC reductions and high DWI scores within 3?h after hanging, which was associated with diffuse anoxic brain damage with poor cerebral performance categories scores. CA comatose survivors had significantly lower ADC values and higher DWI scores compared to non-CA comatose survivors in the cortex and deep grey nuclei.Conclusion
Although the presence of CA is the most important clinical prognosticator in hanging-associated comatose survivors, HSI abnormalities and low ADC values in the cortex and deep grey nuclei on DWI performed within 3?h after hanging are well-correlated with unfavourable outcomes regardless of therapeutic hypothermia. Therefore, early DWI may increase the sensitivity of poor outcome prediction and may be an effective combinatorial screening method when available prognostic variables are not reliable or conclusive. 相似文献93.
Zafar Iqbal Ambreen Iqbal Zaman Ashraf Muhammad Latif Mubashir Hassan Humaira Nadeem 《Drug development research》2019,80(5):646-654
A series of N-(5-(alkylthio)-1,3,4-oxadiazol-2-yl)methyl)benzamides 6a–i were synthesized as alkaline phosphatase inhibitors. The intermediate 5-substituted 1,3,4-oxadiazole-2-thione 4 was synthesized starting with hippuric acid. Hippuric acid in the first step was converted into corresponding methyl ester 2 which upon reaction with hydrazine hydrate furnished the formation of hydrazide 3 . The hippuric acid hydrazide was then cyclized into 5-substituted 1,3,4-oxadiazole-2-thione 4 . The intermediate 4 was then reacted with alkyl or aryl halides 5a–5i to afford the title compounds N-(5-(methylthio)-1,3,4-oxadiazol-2-yl)methyl)benzamides 6a–i . The bioassay results showed that compounds 6a–i exhibited good to excellent alkaline phosphatase inhibitory activity. The most potent activity was exhibited by the compound 6i having IC50 value 0.420 μM, whereas IC50 value of standard (KH2PO4) was 2.80 μM. Molecular docking studies was performed against alkaline phosphatase enzyme (PDBID 1EW2) to check binding affinity of the synthesized compounds 6a–i against target protein. The docking results showed that three compounds 6c , 6e , and 6i have maximum binding interactions with binding energy values of −8 kcal/mol. The compound 6i displayed the interactions of oxadiazole ring nitrogen with amino acid His265 having a binding distance 2.13 Ǻ. It was concluded from our results that synthesized compounds, especially compound 6i may serve as lead structure to design more potent inhibitors of human alkaline phosphatase. 相似文献
94.
Shih-Chuan Chou Justine M. Nagurney Scott G. Weiner Arthur S. Hong J. Frank Wharam 《The American journal of emergency medicine》2019,37(6):1037-1043
ObjectivesTo describe recent trends in advanced imaging and hospitalization of emergency department (ED) syncope patients, both considered “low-value”, and examine trend changes before and after the publication of American College Emergency Physician (ACEP) syncope guidelines in 2007, compared to conditions that had no changes in guideline recommendations.MethodsWe analyzed 2002–2015 National Hospital Ambulatory Medical Care Survey data using an interrupted-time series with comparison series design. The primary outcomes were advanced imaging among ED visits with principal diagnosis of syncope and headache and hospitalization for ED visits with principal diagnosis of syncope, chest pain, dysrhythmia, and pneumonia. We adjusted annual imaging and hospitalization rates using survey-weighted multivariable logistic regression, controlling for demographic and visit characteristics. Using adjusted outcomes as datapoints, we compared linear trends and trend changes of annual imaging and hospitalization rates before and after 2007 with aggregate-level multivariable linear regression.ResultsFrom 2002 to 2007, advanced imaging rates for syncope increased from 27.2% to 42.1% but had no significant trend after 2007 (trend change: ?3.1%; 95%CI ?4.7, ?1.6). Hospitalization rates remained at approximately 37% from 2002 to 2007 but declined to 25.7% by 2015 (trend change: ?2.2%; 95%CI ?3.0, ?1.4). Similar trend changes occurred among control conditions versus syncope, including advanced imaging for headache (difference in trend change: ?0.6%; 95%CI ?2.8, 1.6) and hospitalizations for chest pain, dysrhythmia, and pneumonia (differences in trend changes: 0.1% [95%CI ?1.9, 2.0]; ?0.9% [95%CI ?3.1, 1.3]; and ?1.2% [95%CI ?5.3, 2.9], respectively).ConclusionsBefore and after the release of 2007 ACEP syncope guidelines, trends in advanced imaging and hospitalization for ED syncope visits had similar changes compared to control conditions. Changes in syncope care may, therefore, reflect broader practice shifts rather than a direct association with the 2007 ACEP guideline. Moreover, utilization of advanced imaging remains prevalent. To reduce low-value care, policymakers should augment society guidelines with additional policy changes such as reportable quality measures. 相似文献
95.
目的 探索单能量成像结合自适应统计迭代重建(adaptive statistical iterative reconstruction,ASIR)及自动能谱协议选择(automatic spectral imaging mode selection,ASIS)技术在个体化降低患者门静脉造影辐射剂量、对比剂剂量中的应用价值。方法 回顾性收集华中科技大学同济医学院附属协和医院2017年1月至2017年4月120例临床需进行上腹部增强检查的受检者资料(男80例,女40例),按扫描方案分为3组,每组各40例。A组采用常规120 kVp扫描,噪声指数(NI)=10,对比剂用量为450 mgI/kg,图像采用50% ASIR重建;B、C两组采用能谱成像模式,NI=10(B组),NI=13(C组),对比剂用量均为300 mgI/kg,图像采用60 keV+50% ASIR重建。采用单因素方差分析比较3组图像中门静脉、肝实质的平均CT值及其差值、图像噪声、信噪比(SNR)及对比噪声比(CNR)。由两位高年资放射科医师对3组图像进行主观图像质量评分。记录患者的容积CT剂量指数(CTDIvol)、剂量长度乘积(DLP)并计算有效剂量(E)。结果 B、C两组对比剂用量较A组降低了约30%。A、B、C组图像的门静脉CT值分别为168.22±17.82、209.06±20.07、211.03±25.60,B、C组与A比较,差异有统计学意义(t=-9.625、-8.680,P<0.05)。A、B、C 3组门静脉与肝实质CT差值分别为60.01±17.01、106.63±25.83、107.72±25.39,B、C组与A组比较,差异有统计学意义(t=-9.536、-9.857,P<0.05)。SNR分别为8.48±1.41、12.64±2.94、10.77±1.94,CNR分别为5.16±1.80、8.13±2.54、7.32±1.84,图像质量评分分别为(3.53±0.68)、(4.75±0.54)和(4.53±0.64)分,B、C组的SNR、CNR和图像质量评分与A组比较,差异有统计学意义(t=-8.082、-6.064、-6.050、-5.308、-8.912、-6.779,P<0.05)。A、B、C组CTDIvol分别为(12.15±5.02)、(12.34±4.18)、(10.03±3.13)mGy,DLP分别为(348.62±155.99)、(355.56±131.07)、(287.10±92.25)mGy·cm,E分别为(5.23±2.34)、(5.33±1.97)、(4.31±1.38)mSv,相对于A、B两组,C组的CTDIvol、DLP和E差异均有统计学意义(t=2.274、2.147、2.147、2.812、2.702、2.702,P<0.05),分别降低了19%。结论 CT门静脉成像时,选择NI=13,60 keV结合50%ASIR重建及ASIS技术可以个体化降低患者的对比剂剂量和辐射剂量,并提供满足诊断要求的图像。 相似文献
96.
Azusa Ikeda Yoshihiro Watanabe Hikari Kaba Kimihiko Kaneko Toshiyuki Takahashi Saoko Takeshita 《Brain & development》2019,41(4):367-372
Background
Myelin oligodendrocyte glycoprotein antibodies (MOG Abs) are frequently detected in pediatric acquired demyelinating syndrome (ADS), and MOG-Ab-positive ADS differs from multiple sclerosis (MS) and aquaporin-4 (AQP4)-Ab-positive neuromyelitis optica spectrum disorder (NMOSD) in terms of age distribution, therapeutic response, and prognosis.Methods
Based on medical records, we retrospectively evaluated patients with MOG-Ab-positive NMOSD treated in the acute phase who were followed up in the chronic phase at our hospital from January 2011 to December 2017.Results
The patients comprised two boys and two girls aged 3–12 (median, 8) years. Peak MOG-Ab titers were 1:2048 to 1:32768 (median, 1:10240), and the relapse rate ranged from 0 to 1.25 times/year (median, 0.59 times/year); no sequelae were observed in any cases. Lesions other than those of optic neuritis were distributed at the cortex in one patient, subcortical white matter in four, deep white matter in three, and brainstem in one, all of which were disseminated lesions. No lesions were found in the corpus callosum, periventricular white matter, diencephalon, and regions adjacent to the third and fourth ventricles. The lesions tended to be asymptomatic, and two patients aged >5?years had well-demarcated lesions.Conclusion
All the patients showed disseminated lesions in the subcortical region to deep white matter, which were different from those found in MS and AQP4-Ab-positive NMOSD and were consistent with the characteristics of brain lesions in MOG-Ab-positive ADS, including other disease types. 相似文献97.
98.
99.
射血分数保留的心力衰竭发病率在逐年上升。准确测量左室舒张功能有利于对该病的临床评价。目前可采用超声心动图、心脏MRI(CMRI)及其他多种检查方法评价左室舒张功能,并对舒张功能的病生理机制、舒张功能障碍分级有提示作用。其中CMRI技术的作用日益突出,包括舒张期容积-时间曲线、二尖瓣血流与肺静脉血流成像、心肌标记及其他CMRI技术。 相似文献
100.
David M. Glassman Erik Magnusson Julie Agel Carlo Bellabarba Richard J. Bransford 《The spine journal》2019,19(4):687-694