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11.
目的:探讨MRI在浸润性小叶癌(ILC)术前诊断中的应用价值,并评估乳腺密度对其影响。方法:选取75例术前30天内行MRI检查的I-Ⅲ期ILC患者列入本项研究,根据腺体含量评估乳腺密度,在MRI下测量肿瘤大小,并对比其与病理大小的一致性。结果:75例入组患者中26例(34.7%)患者经MRI评估发现新的可疑病灶,20例(26.7%)患者改变了手术方式。高密度乳腺型患者额外病灶检出率明显高于低密度乳腺型患者(51.6% vs 22.7%,P=0.010)。MRI评估肿瘤大小在低密度乳腺型患者中容易被低估(36.4% vs 12.9%,P=0.024),在高密度乳腺型患者中容易被高估(6.8% vs 29.0%,P=0.010),但两组患者与病理大小一致性的比例无明显差异。结论:ILC患者术前乳腺MRI检查能够提高额外恶性肿瘤的检出率,而乳腺密度是影响MRI评估的重要因素。 相似文献
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《Journal of the American College of Radiology》2020,17(3):384-390
PurposeEffective written communication directly affects health care outcomes. Since 2016, the complex language of state-mandated breast density notifications (BDNs) has been challenged, because it is perceived to be beyond the comprehension of most patients. The aim of this study was to assess whether a revised BDN written at a lower reading grade level improves understanding compared with the current state-mandated BDN.MethodsA revised notification with similar content to the current state-mandated BDN was developed. Both notifications were presented to patients for direct comparison, using a paper survey asking questions that evaluated patients’ perceptions and convictions associated with breast density. Surveys were distributed at four outpatient imaging centers to screening mammography patients.ResultsThe current BDN’s mean readability metric was 13.4, and that of the revised BDN was 6.6. Five hundred surveys were analyzed. Survey data demonstrated that 56.6% of all women perceived that dense breast tissue results indicated a “high” associated lifetime breast cancer risk from the current state-mandated BDN compared with only 2.2% with the revised notification (P < .001). Nearly all women were more likely to initiate discussions with their providers regarding their breast tissue density after reading the revised notification (96.0%) as opposed to the current state-mandated BDN (32.8%; P < .001).ConclusionsA significant portion of women misinterpret the intended messages of the current state-mandated BDN. Thus, a revised notification at a lower reading grade level may improve understanding of breast density, leading to improved individualized breast cancer screening for women with dense breasts. 相似文献
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《Diagnostic and interventional imaging》2020,101(9):555-564
PurposeThe purpose of this study was to determine whether computed tomography (CT)-based machine learning of radiomics features could help distinguish autoimmune pancreatitis (AIP) from pancreatic ductal adenocarcinoma (PDAC).Materials and MethodsEighty-nine patients with AIP (65 men, 24 women; mean age, 59.7 ± 13.9 [SD] years; range: 21–83 years) and 93 patients with PDAC (68 men, 25 women; mean age, 60.1 ± 12.3 [SD] years; range: 36–86 years) were retrospectively included. All patients had dedicated dual-phase pancreatic protocol CT between 2004 and 2018. Thin-slice images (0.75/0.5 mm thickness/increment) were compared with thick-slices images (3 or 5 mm thickness/increment). Pancreatic regions involved by PDAC or AIP (areas of enlargement, altered enhancement, effacement of pancreatic duct) as well as uninvolved parenchyma were segmented as three-dimensional volumes. Four hundred and thirty-one radiomics features were extracted and a random forest was used to distinguish AIP from PDAC. CT data of 60 AIP and 60 PDAC patients were used for training and those of 29 AIP and 33 PDAC independent patients were used for testing.ResultsThe pancreas was diffusely involved in 37 (37/89; 41.6%) patients with AIP and not diffusely in 52 (52/89; 58.4%) patients. Using machine learning, 95.2% (59/62; 95% confidence interval [CI]: 89.8–100%), 83.9% (52:67; 95% CI: 74.7–93.0%) and 77.4% (48/62; 95% CI: 67.0–87.8%) of the 62 test patients were correctly classified as either having PDAC or AIP with thin-slice venous phase, thin-slice arterial phase, and thick-slice venous phase CT, respectively. Three of the 29 patients with AIP (3/29; 10.3%) were incorrectly classified as having PDAC but all 33 patients with PDAC (33/33; 100%) were correctly classified with thin-slice venous phase with 89.7% sensitivity (26/29; 95% CI: 78.6–100%) and 100% specificity (33/33; 95% CI: 93–100%) for the diagnosis of AIP, 95.2% accuracy (59/62; 95% CI: 89.8–100%) and area under the curve of 0.975 (95% CI: 0.936–1.0).ConclusionsRadiomic features help differentiate AIP from PDAC with an overall accuracy of 95.2%. 相似文献
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Monika Scheer Christian Vokuhl Iris Veit‐Friedrich Marc Münter Thekla von Kalle Michael Greulich Steffan Loff Sabine Stegmaier Monika Sparber‐Sauer Felix Niggli Ruth Ladenstein Bernarda Kazanowska Gustaf Ljungman Kirsi Jahnukainen Jrg Fuchs Stefan S. Bielack Ewa Koscielniak Thomas Klingebiel 《Pediatric blood & cancer》2020,67(2)
18.
目的观察叶酸和维生素B12对绝经后骨质疏松症妇女的骨代谢及同型半胱氨酸水平的影响。方法 80例绝经后骨质疏松症妇女参加研究。所有参与者随机接受叶酸和维生素B12(n=40)或安慰剂(n=40)治疗。在干预前的基线及干预后3个月和6个月,测量两组患者血清同型半胱氨酸、维生素B12和骨代谢标志物的水平。结果治疗前,两组患者血清同型半胱氨酸、维生素B12和骨代谢标志物水平比较差异无统计学意义(P0.05)。治疗后,两组患者同型半胱氨酸均下降,但比较差异无统计学意义(P0.05)。6个月后各组间血清维生素B12、骨钙素、CTX的变化均有显著改变且差异有统计学意义(P0.05)。结论绝经后骨质疏松症妇女补充叶酸和维生素B12可以一定程度改善同型半胱氨酸及骨代谢指标水平。 相似文献
19.
目的探究卡马西平与左乙拉西坦治疗成人癫痫的效果及对认知功能、骨密度的影响。方法92例成人癫痫患者作为研究对象,随机分为左乙拉西坦组与卡马西平组,各46例。左乙拉西坦组采用左乙拉西坦治疗,卡马西平组采用卡马西平治疗。比较两组患者治疗前及治疗6个月后认知功能[语言智商(VIQ)、操作智商(PIQ)、总智商(FIQ)]评分、骨密度(腰椎、股骨大转子、股骨颈)变化情况。结果治疗6个月后,两组患者VIQ、PIQ、FIQ评分均较治疗前显著提升,且左乙拉西坦组患者VIQ评分(101.2±3.1)分、PIQ评分(108.1±2.3)分、FIQ评分(105.2±1.8)分均明显高于卡马西平组的(95.1±2.8)、(94.1±2.0)、(93.5±1.6)分,差异有统计学意义(P<0.05)。治疗6个月后,卡马西平组患者腰椎、股骨大转子、股骨颈骨密度均较治疗前显著下降,且明显低于卡马西平组,差异有统计学意义(P<0.05);左乙拉西坦组治疗6个月后腰椎、股骨大转子、股骨颈骨密度与治疗前比较差异无统计学意义(P>0.05)。结论左乙拉西坦与卡马西平治疗成人癫痫,左乙拉西坦更能明显提升患者认知功能,且对患者骨密度无影响。 相似文献
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《The ocular surface》2020,18(4):926-935
PurposeTo visualize and quantify vascular networks in individuals with ocular surface squamous neoplasia (OSSN) through optical coherence tomography angiography (OCTA).MethodCross-sectional study of OSSN patients. Vascular networks were measured by OCTA in the epithelium and sub-epithelial space in the tumors, adjacent tissue, and in the contralateral eye. Vessel area density (VAD, percent of blood vessels within 2.14 mm2), was calculated for each location. Total tumor density (TTD, percent of blood vessels within the entire tumor) was calculated. VAD was assessed separately for corneal and conjunctival locations and compared.ResultsFifteen patients with OSSN were included. The mean age was 61 ± 12 years and the majority were male (80%). The mean tumor area, volume, depth, and TTD were 28.0 ± 9.0 mm2 (range, 10.9–39.7), 9.1 ± 4.1 mm3 (range, 3.4–18.8), 334 ± 125 μm (range, 177–571), and 33.2% ± 11.0% (range, 18.7–58.8), respectively. The VAD was highest within the tumor (28.9% ± 8.7%) followed by the adjacent sub-epithelial tissue and the tissue underneath the conjunctival component of tumor. These densities were higher than the VAD in the tissues of the non-involved eye (all P < 0.05). The VAD within conjunctival component of tumor was significantly higher than those with corneal component (29.8% ± 9.5% vs. 21.1% ± 5.5%, p = 0.006). The VAD under conjunctival tumor was also significantly higher than under corneal component (24.1% ± 7.8% vs. 17.0% ± 6.1%, p = 0.024).ConclusionsOCTA imaging allowed for visualization and quantification of vessel structure and density within, under, and surrounding OSSN. 相似文献