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31.
目的 应用锥形束CT(cone beam CT,CBCT)测量种植区牙槽骨质量并结合Lekholm和Zarb分类法对骨质量分类方法进行改良,以期为提高牙槽骨质量分类的准确性提供指导。方法 选择2015年10月至2017年10月在呼和浩特市口腔医院种植科进行种植修复的196例患者术前CBCT影像资料,应用 Invivo5诊断设计软件测量306个种植位点的牙槽骨皮质骨厚度和松质骨密度(皮质骨与松质骨的CT值差值),以Lekholm和Zarb分类法为基础结合测量数据对骨质量进行改良后的量化分类。结果 牙槽骨皮质骨厚度为0.18 ~ 2.89 mm,中位数为0.92 mm。皮质骨与松质骨的CT值差值为88.5 ~ 667.8 HU,应用百分位数法找到33.3%和66.6%对应的数值分别为297.8 HU和356.1 HU。依据此数据结合Lekholm和Zarb分类法将196例患者的306个种植位点骨质量分为4类,其中Ⅰ类骨种植位点46个(占15.0%),Ⅱ类骨104个(占34.0%),Ⅲ类骨114个(占37.3%),Ⅳ类骨42个(占13.7%)。结论 结合Lekholm和Zarb分类法,应用CBCT测量种植区牙槽骨质量并进行分类方法的改良,可为临床医生术前评估牙槽骨质量提供一定参考。 相似文献
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目的采用Meta分析方法评价18F-脱氧葡萄糖正电子发射计算机体层摄影(18F-FDG PET/CT)和增强CT(CECT)诊断经导管肝动脉化疗栓塞术(TACE)术后存活或复发病灶的临床价值。方法根据PRISMA报告规范开展Meta分析。检索PubMed、Embase、Cochrane Library、Web of Science、中国知网、万方和维普数据库中18F-FDG PET/CT和CECT诊断TACE术后存活或复发病灶的临床研究,时间至2019-04。由2位研究人员独立筛选文献、提取资料,根据诊断准确性研究质量评价工具-2(QUADAS-2)评价纳入研究的偏倚风险后,采用Stata 12.0软件进行Meta分析,计算其汇总敏感度(Sen)和特异度(Spe),绘制受试者工作特征曲线(SROC)并计算曲线下面积(AUC)。结果共纳入10篇18F-FDG PET/CT及13篇CECT诊断TACE术后存活或复发病灶的原始研究,分别包括322例患者的467个病灶和748例患者的943个病灶。Meta分析显示,18F-FDG PET/CT诊断TACE术后存活或复发病灶的Sen=0.92(95%CI为0.87~0.94)、Spe=0.95(95%CI为0.82~0.99)、AUC=0.97(95%CI为0.93~0.99);CECT诊断TACE术后存活或复发病灶的Sen=0.72(95%CI为0.66~0.78)、Spe=0.99(95%CI为0.93~1.00)、AUC=0.87(95%CI为0.83~0.89)。此外,CECT诊断TACE术后存活或复发Sen(Z=2.34,P=0.02)和AUC(Z=2.21,P=0.03)值低于18F-FDG PET/CT,差异有统计学意义。结论相比于CECT,18F-FDG PET/CT对TACE术后存活或复发病灶具有较高诊断效能,可视为TACE术后存活或复发病灶有效的影像学诊断方法。 相似文献
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AimTo compare the accuracy of the inverted greyscale CT versus the conventional CT in the assessment of post-operative spinal orthopaedic implants and osseous fusion.Methods50 patients who had CT as part of their routine spinal implant follow up were evaluated for the presence of fusion, fracture and loosening with conventional CT and with greyscale inverted CT images. 3 independent observers assessed the images 2 months apart. Diagnostic performance (sensitivity and specificity) of the conventional and greyscale inversion images relative to the reference standard were calculated. Agreement with the reference standard was assessed using Cohen's kappa for conventional and greyscale inversion images.ResultsCorrect classifications increased when using the greyscale inverted CT images for each reader compared to conventional CT images (40–46, 39 to 42 and 41 to 44 (out of 50)). Inverted images demonstrated better agreement with the reference standard than conventional grayscale images for assessment of fusion (kappa of 0.588 for inverted CT versus 0.484 for conventional CT) and loosening (kappa 0.386 for inverted versus 0.293 for conventional). Sensitivity was increased for assessment of fusion and loosening. McNemar's test performed for assessment of sensitivity differences showed statistical significance (p = 0.038 for fusion and p = 0.0313 for loosening).ConclusionGreyscale inversion CT is a useful adjunct which has advantages (improved sensitivity and better agreement) over conventional CT imaging in cases of fusion and loosening of metallic implants following spinal instrumentation. We recommend the use of both the greyscale inversion CT images and conventional CT imaging when assessing post-operative spinal orthopaedic implants. 相似文献
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IntroductionDespite advancements in surgical techniques complications like implant failure is very common after the fixation of intertrochanteric fractures. Classifying these complex fractures based on plain radiographs underestimates the complexity of these fractures which in turn leads to complications. We propose a comprehensive classification of the intertrochanteric fractures based on 3D Non Contrast Computed Tomography (3D NCCT) scan.Material and methodsA total of 102 patients (51 males and 51 females) with intertrochanteric fractures were included in this study conducted over a time period of 22 months in a Tertiary care center in North India. NCCT proximal femur of the intertrochanteric fracture patients was done to formulate a new CT classification system and classify all fractures. Intra and inter-observer reliability was tested using kappa variance.ResultsNew classification system was proposed which included 3 main and a total of 6 groups. All the fractures were classifiable into the new system. Kappa variance of the study showed a good intra and interobserver reliability (0.95 and 0.90) proving clinical agreement of the classification.ConclusionThis new 3D-CT based classification has the advantages of being easy, comprehensible with high intra and inter-observer reliability. This 3DCT based classification can prove to be useful to detect occult intertrochanteric fractures undetectable in plain radiographs as well as choosing the optimum treatment plan. 相似文献
36.
Stress Testing Versus CT Angiography in Patients With Diabetes and Suspected Coronary Artery Disease
Abhinav Sharma Adrian Coles Nishant K. Sekaran Neha J. Pagidipati Michael T. Lu Daniel B. Mark Kerry L. Lee Hussein R. Al-Khalidi Udo Hoffmann Pamela S. Douglas 《Journal of the American College of Cardiology》2019,73(8):893-902
Background
The optimal noninvasive test (NIT) for patients with diabetes and stable symptoms of coronary artery disease (CAD) is unknown.Objectives
The purpose of this study was to assess whether a diagnostic strategy based on coronary computed tomographic angiography (CTA) is superior to functional stress testing in reducing adverse cardiovascular (CV) outcomes (CV death or myocardial infarction [MI]) among symptomatic patients with diabetes.Methods
PROMISE (Prospective Multicenter Imaging Study for Evaluation of Chest Pain) was a randomized trial evaluating an initial strategy of CTA versus functional testing in stable outpatients with symptoms suggestive of CAD. The study compared CV outcomes in patients with diabetes (n = 1,908 [21%]) and without diabetes (n = 7,058 [79%]) based on their randomization to CTA or functional testing.Results
Patients with diabetes (vs. without) were similar in age (median 61 years vs. 60 years) and sex (female 54% vs. 52%) but had a greater burden of CV comorbidities. Patients with diabetes who underwent CTA had a lower risk of CV death/MI compared with functional stress testing (CTA: 1.1% [10 of 936] vs. stress testing: 2.6% [25 of 972]; adjusted hazard ratio: 0.38; 95% confidence interval: 0.18 to 0.79; p = 0.01). There was no significant difference in nondiabetic patients (CTA: 1.4% [50 of 3,564] vs. stress testing: 1.3% [45 of 3,494]; adjusted hazard ratio: 1.03; 95% confidence interval: 0.69 to 1.54; p = 0.887; interaction term for diabetes p value = 0.02).Conclusions
In diabetic patients presenting with stable chest pain, a CTA strategy resulted in fewer adverse CV outcomes than a functional testing strategy. CTA may be considered as the initial diagnostic strategy in this subgroup. (PROspective Multicenter Imaging Study for Evaluation of Chest Pain [PROMISE]; NCT01174550) 相似文献37.
《Journal of Cardiovascular Computed Tomography》2019,13(5):254-260
Invasive coronary plaque imaging such as intravascular ultrasound and optical coherence tomography has been widely used to observe culprit or non-culprit coronary atherosclerosis, as well as optimize stent sizing, apposition and deployment. Coronary computed tomographic angiography (CTA) is non-invasively available to assess coronary artery disease (CAD) and has become an appropriate strategy to evaluate patients with suspected CAD. Given recent technologies, semi-automated plaque software is available to identify coronary plaque stenosis, volume and characteristics and potentially allows to be used for the assessment of more details of plaque information, progression and future risk as a surrogate tool of the invasive imaging modalities. This review article aims to focus on various evidence in coronary plaque imaging by coronary CTA and describes how accurate coronary CTA can classify coronary atherosclerosis. 相似文献
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