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目的:探讨中期正电子发射型计算机断层显像(positron emission tomography-computed tomography,PET-CT)Deauville五分法(Deauville five-point scale,5-PS)与最大标准摄取值缩减率(maximum standard uptake value variation,△SUVmax)两种图像判读法在弥漫性大B细胞淋巴瘤(diffuse large B-cell lymphoma,DLBCL)患者预后评估中的应用价值。方法:回顾性分析2012年10月至2018年6月重庆医科大学附属第一医院收治的94例DLBCL患者资料。采用Kaplan-Meier法及Cox比例风险回归模型进行生存资料分析,计算并采用χ2检验比较5-PS和△SUVmax对DLBCL患者预后预测的能力。结果:5-PS和△SUVmax分别以4分、86%进行分组。5-PS<4分组、△SUVmax≥86%组的患者无进展生存期(progression free survival,PFS)和总生存期(overall survival,OS)均优于5-PS≥4分组、△SUVmax<86%组的患者(P<0.05)。△SUVmax与5-PS对患者PFS和OS均有影响,较高的阴性预测值(89.4%,93.6%;76.1%,85.9%),较低的阳性预测值(48.9%,31.9%;47.8%,34.8%),并且△SUVmax对于患者的敏感性优于5-PS(82.1%,83.3%vs.39.3%,44.4%)。单因素分析中国际预后指数(international prognostic index,IPI)(P=0.007)、△SUVmax(P<0.001)、5-PS(P=0.014)及基线全身肿瘤代谢体积(total metabolic tumor volume,TMTV)(P=0.001)与PFS相关,△SUVmax(P=0.014)、5-PS(P=0.033)、TMTV(P=0.004)与OS相关;多因素分析显示TMTV是OS的独立预测因子(P=0.005),△SUVmax和TMTV是PFS的独立预测因子(P=0.002,P=0.020),并且△SUVmax<86%且高水平TMTV患者较低TMTV患者的PFS明显缩短(P=0.001)。结论:5-PS和△SUVmax均能初步评估DLBCL患者预后,但△SUVmax具有更高的预测价值,并且联合基线TMTV可以对DLBCL患者进行再次危险度分层。  相似文献   
33.
BackgroundData on left ventricular (LV) deformation imaging using CT angiography (CTA) are scarce and the feasibility of atrial deformation analysis by CT has not been addressed. We aimed to compare 2D echocardiographic and CT derived LV and left atrial (LA) global longitudinal strain (GLS) obtained by using a novel feature tracking algorithm in patients following transcatheter aortic valve implantation.MethodsTwenty-eight patients were included who underwent retrospectively-gated 256-slice CTA and speckle-tracking echocardiography (STE) on the same day. CT datasets in 10% increments were reconstructed throughout the cardiac cycle. LV GLS and LA global peak reservoir strain (LA GS) was measured.ResultsMedian absolute values for LV GLS were 19.9 [14.8–22.4] vs. 19.9 [16.8–24.7], as measured by CT vs STE, respectively (p = 0.017). We found good inter-modality correlation for LV GLS (ρ = 0.78, p < 0.05) with a mean bias of −1.6. Regarding atrial measurements, the median LA GS was 19.0 [13.5–27.3] for CT vs. 28.0 [17.5–32.6] for STE (p < 0.001) with a mean bias of −5.6 between CT and STE and a correlation coefficient of ρ = 0.87, p < 0.001. CT measurements were highly reproducible: intra-observer intra-class correlation coefficient was 0.96 for LV GLS and 0.95 for LA GS.ConclusionWe detected good correlation between CTA and echocardiography-based LV and LA longitudinal strain parameters. CTA provides accurate strain measurements with high reproducibility. Feature tracking-based deformation analysis could provide a clinically important addition to CT examinations by complementing anatomical information with functional data.  相似文献   
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ObjectiveTo compare the lumen parameters measured by the location-adaptive threshold method (LATM), in which the inter- and intra-scan attenuation variabilities of coronary computed tomographic angiography (CCTA) were corrected, and the scan-adaptive threshold method (SATM), in which only the inter-scan variability was corrected, with the reference standard measurement by intravascular ultrasonography (IVUS).Materials and MethodsThe Hounsfield unit (HU) values of whole voxels and the centerline in each of the cross-sections of the 22 target coronary artery segments were obtained from 15 patients between March 2009 and June 2010, in addition to the corresponding voxel size. Lumen volume was calculated mathematically as the voxel volume multiplied by the number of voxels with HU within a given range, defined as the lumen for each method, and compared with the IVUS-derived reference standard. Subgroup analysis of the lumen area was performed to investigate the effect of lumen size on the studied methods. Bland-Altman plots were used to evaluate the agreement between the measurements.ResultsLumen volumes measured by SATM was significantly smaller than that measured by IVUS (mean difference, 14.6 mm3; 95% confidence interval [CI], 4.9–24.3 mm3); the lumen volumes measured by LATM and IVUS were not significantly different (mean difference, −0.7 mm3; 95% CI, −9.1–7.7 mm3). The lumen area measured by SATM was significantly smaller than that measured by LATM in the smaller lumen area group (mean of difference, 1.07 mm2; 95% CI, 0.89–1.25 mm2) but not in the larger lumen area group (mean of difference, −0.07 mm2; 95% CI, −0.22–0.08 mm2). In the smaller lumen group, the mean difference was lower in the Bland-Altman plot of IVUS and LATM (0.46 mm2; 95% CI, 0.27–0.65 mm2) than in that of IVUS and SATM (1.53 mm2; 95% CI, 1.27–1.79 mm2).ConclusionSATM underestimated the lumen parameters for computed lumen segmentation in CCTA, and this may be overcome by using LATM.  相似文献   
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Diabetic macular ischaemia (DMI) is traditionally defined and graded based on the angiographic evidence of an enlarged and irregular foveal avascular zone. However, these anatomical changes are not surrogate markers for visual impairment. We postulate that there are vascular phenotypes of DMI based on the relative perfusion deficits of various retinal capillary plexuses and choriocapillaris. This review highlights several mechanistic pathways, including the role of hypoxia and the complex relation between neurons, glia, and microvasculature. The current animal models are reviewed, with shortcomings noted. Therefore, utilising the advancing technology of optical coherence tomography angiography (OCTA) to identify the reversible DMI phenotypes may be the key to successful therapeutic interventions for DMI. However, there is a need to standardise the nomenclature of OCTA perfusion status. Visual acuity is not an ideal endpoint for DMI clinical trials. New trial endpoints that represent disease progression need to be developed before irreversible vision loss in patients with DMI. Natural history studies are required to determine the course of each vascular and neuronal parameter to define the DMI phenotypes. These DMI phenotypes may also partly explain the development and recurrence of diabetic macular oedema. It is also currently unclear where and how DMI fits into the diabetic retinopathy severity scales, further highlighting the need to better define the progression of diabetic retinopathy and DMI based on both multimodal imaging and visual function. Finally, we discuss a complete set of proposed therapeutic pathways for DMI, including cell-based therapies that may provide restorative potential.  相似文献   
38.

Background

There were few studies assessed the postoperative sarcopenia in patients with cancers. The objective of present study was to assess whether postoperative development of sarcopenia could predict a poor prognosis in patients with adenocarcinoma of esophagogastric junction, (AEG) and upper gastric cancer (UGC).

Methods

Patients with AEG and UGC who were judged as non-sarcopenic before surgery were reassessed the presence of postoperative development of sarcopenia 6 months after surgery. Patients were divided into the development group or non-development group, and clinicopathological factors and prognosis between these two groups were analyzed.

Results

The 5-year overall survival rates were significantly poorer in the development group than non-development group (68.0% vs. 92.6%, P?=?0.0118). Multivariate analyses showed that postoperative development of sarcopenia was an independent prognostic factor for poor overall survival (P?=?0.0237).

Conclusions

Postoperative development of sarcopenia was associated with a poor prognosis in patients with AEG and UGC.  相似文献   
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BackgroundIn patients with melanoma, sentinel lymph node (SLN) status is pivotal for treatment decisions. Current routine for SLN detection combines Technetium99m (Tc99) lymphoscintigraphy and blue dye (BD). The primary aim of this study was to examine the feasibility of using a low dose of superparamagnetic iron oxide (SPIO) injected intracutaneously to detect and identify the SLN, and the secondary aim was to investigate if a low dose of SPIO would enable a preoperative MRI-evaluation of SLN status.MethodsPatients with melanoma of the extremities were eligible. Before surgery, a baseline MRI of the nodal basin was followed by an injection of a low dose (0.02–0.5 mL) of SPIO and then a second MRI (SPIO-MRI). Tc99 and BD was used in parallel and all nodes with a superparamagnetic and/or radioactive signal were harvested and analyzed.ResultsFifteen patients were included and the SLNB procedure was successful in all patients (27 SLNs removed). All superparamagnetic SLNs were visualized by MRI corresponding to the same nodes on scintigraphy. Micrometastatic deposits were identified in four SLNs taken from three patients, and SPIO-MRI correctly predicted two of the metastases. There was an association between MRI artefacts in the lymph node and the dose SPIO given.DiscussionIt is feasible to detect SLN in patients with melanoma using a low dose of SPIO injected intracutaneously compared with the standard dual technique. A low dose of SPIO reduces the lymph node MRI artefacts, opening up for a non-invasive assessment of SLN status in patients with cancer.  相似文献   
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