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21.
Yong-Kyu Kim Cheolkyu Jung Se Joon Woo Kyu Hyung Park 《Journal of Korean medical science》2015,30(12):1847-1855
Cosmetic facial filler-related ophthalmic artery occlusion is rare but is a devastating complication, while the exact pathophysiology is still elusive. Cerebral angiography provides more detailed information on blood flow of ophthalmic artery as well as surrounding orbital area which cannot be covered by fundus fluorescein angiography. This study aimed to evaluate cerebral angiographic features of cosmetic facial filler-related ophthalmic artery occlusion patients. We retrospectively reviewed cerebral angiography of 7 patients (4 hyaluronic acid [HA] and 3 autologous fat-injected cases) showing ophthalmic artery and its branches occlusion after cosmetic facial filler injections, and underwent intra-arterial thrombolysis. On selective ophthalmic artery angiograms, all fat-injected patients showed a large filling defect on the proximal ophthalmic artery, whereas the HA-injected patients showed occlusion of the distal branches of the ophthalmic artery. Three HA-injected patients revealed diminished distal runoff of the internal maxillary and facial arteries, which clinically corresponded with skin necrosis. However, all fat-injected patients and one HA-injected patient who were immediately treated with subcutaneous hyaluronidase injection showed preserved distal runoff of the internal maxillary and facial arteries and mild skin problems. The size difference between injected materials seems to be associated with different angiographic findings. Autologous fat is more prone to obstruct proximal part of ophthalmic artery, whereas HA obstructs distal branches. In addition, hydrophilic and volume-expansion property of HA might exacerbate blood flow on injected area, which is also related to skin necrosis. Intra-arterial thrombolysis has a limited role in reconstituting blood flow or regaining vision in cosmetic facial filler-associated ophthalmic artery occlusions. 相似文献
22.
目的 检测中国汉族健康人群的肝脏脂肪分数及肝储铁水平,并评价脂肪分数及肝储铁水平相关性。方法 应用GE Discovery MR750W测定45名受检者的肝脏脂肪分数和R2*值。采用IdealIQ序列进行上腹部扫描,应用AW VolumeShare 5工作站软件,通过在肝脏上选择ROI的方法直接获得R2*值及肝脂肪分数。采用t检验的方法分别检验不同性别、年龄组间脂肪分数、R2*值均数的差异,应用Spearman分析的方法分析R2*值及脂肪分数的相关性。结果 45名健康人肝脏脂肪分数为1.15%~10.26%,R2*值为46.45~89.30 Hz。男性与女性、青年人与中年人的肝脏FF、R2*值差异均无统计学意义(P均> 0.05)。脂肪分数与R2*值呈线性正相关(r=0.432,P=0.003)。结论 运用3.0T MRI IdealIQ序列能够同时测定肝脏脂肪含量及铁浓度,肝脏脂肪含量与肝铁浓度具有显著的相关性。 相似文献
23.
目的 探讨腰椎骨质密度(BMD)与年龄、性别、体质参数及腹部皮下脂肪(SAT)、内脏脂肪(VAT)的关系。方法 纳入健康志愿者或慢性腰腿痛患者111人(男56人,女55人),测量受检者身高、体质量及腰围,计算体质指数(BMI);采用定量CT(QCT)行腹部扫描,测量L3的BMD及相应层面腹部SAT与VAT含量。将男性与女性分别分为骨质疏松组、骨量减少组和骨量正常组,分别比较3组间年龄、性别、身高、体质量、BMI、腰围、SAT和VAT的差异,对BMD与存在显著性差异的指标进行相关性分析。结果 3组男性间除年龄的差异有统计学意义(P<0.05)外,身高、体质量、BMI、腰围、SAT及VAT的差异均无统计学意义(P均>0.05);男性BMD与年龄呈负相关(r=-0.680,P<0.05)。3组女性年龄、腰围及VAT的差异有统计学意义(P均<0.05),身高、体质量、BMI、SAT差异均无统计学意义(P均>0.05);女性BMD与年龄、腰围、VAT均呈负相关(r= -0.849、-0.412、-0.501,P均<0.05)。结论 男、女性腰椎BMD与年龄均呈明显负相关,与身高、体质量、BMI无明显相关性;男性腰椎BMD与腰围、SAT与VAT均无明显相关性,但女性腰椎BMD与腰围及VAT关系密切。 相似文献
24.
Peter Kellman W Patricia Bandettini Christine Mancini Sophia Hammer-Hansen Michael S Hansen Andrew E Arai 《Journal of cardiovascular magnetic resonance》2015,17(1)
Background
Quantitative measurement of T1 in the myocardium may be used to detect both focal and diffuse disease processes such as interstitial fibrosis or edema. A partial volume problem exists when a voxel in the myocardium also contains fat. Partial volume with fat occurs at tissue boundaries or within the myocardium in the case of lipomatous metaplasia of replacement fibrosis, which is commonly seen in chronic myocardial infarction. The presence of fat leads to a bias in T1 measurement. The mechanism for this artifact for widely used T1 mapping protocols using balanced steady state free precession readout and the dependence on off-resonance frequency are described in this paper.Methods
Simulations were performed to illustrate the behavior of mono-exponential fitting to bi-exponential mixtures of myocardium and fat with varying fat fractions. Both inversion recovery and saturation recovery imaging protocols using balanced steady state free precession are considered. In-vivo imaging with T1-mapping, water/fat separated imaging, and late enhancement imaging was performed on subjects with chronic myocardial infarction.Results
In n = 17 subjects with chronic myocardial infarction, lipomatous metaplasia is evident in 8 patients (47%). Fat fractions as low as 5% caused approximately 6% T1 elevation for the out-of-phase condition, and approximately 5% reduction of T1 for the in-phase condition. T1 bias in excess of 1000 ms was observed in lipomatous metaplasia with fat fraction of 38% in close agreement with simulation of the specific imaging protocols.Conclusions
Measurement of the myocardial T1 by widely used balanced steady state free precession mapping methods is subject to bias when there is a mixture of water and fat in the myocardium. Intramyocardial fat is frequently present in myocardial scar tissue due lipomatous metaplasia, a process affecting myocardial infarction and some non-ischemic cardiomyopathies. In cases of lipomatous metaplasia, the T1 biases will be additive or subtractive depending on whether the center frequency corresponds to the myocardium and fat being in-phase or out-of-phase, respectively. It is important to understand this mechanism, which may otherwise lead to erroneous interpretation. 相似文献25.
Aims/hypothesis The aim of this study was to explore whether fat cell size in human subcutaneous and omental adipose tissue is independently
related to insulin action and adipokine levels.
Materials and methods Fat cells were prepared from abdominal subcutaneous biopsies obtained from 49 type 2 diabetic and 83 non-diabetic subjects
and from omental biopsies obtained from 37 non-diabetic subjects. Cell size and insulin action on glucose uptake capacity
in vitro were assessed in isolated fat cells. Insulin sensitivity in vivo was assessed with euglycaemic-hyperinsulinaemic
clamps. Fasting blood samples were collected and adipokines and NEFA were measured.
Results Negative correlations were found between subcutaneous fat cell size and insulin sensitivity assessed as M-value during clamp and as insulin action on glucose uptake in fat cells in vitro. This was seen in non-diabetic subjects
after including age, sex and BMI in the analyses. No such relationship was found in type 2 diabetic subjects. In both groups,
subcutaneous fat cell size correlated positively and independently with plasma levels of leptin but not to any of the other
assessed adipokines. In non-diabetic subjects, omental fat cell size was independently and negatively correlated with insulin
action in subcutaneous, but not omental, fat cells in vitro.
Conclusions/interpretation Fat cell enlargement is associated with insulin resistance in non-diabetic individuals independently of BMI. This was not
seen in type 2 diabetic subjects, suggesting that after development of type 2 diabetes other factors, not related to fat cell
size, become more important for the modulation of insulin resistance. 相似文献
26.
目的:尝试建立基层医院肠外营养(PN)临床合理应用评价方法。方法:收集脂肪乳氨基酸(17)葡萄糖(11%)注射液的使用病例进行调查,统计分析病例资料的完整性,评价配伍用药情况,计算基础代谢值(BMR)并作相关评估。结果:营养风险评估基本参数不全的病例占66.7%,各病例疗程差异显著但用量无差别,脂肪乳氨基酸(17)葡萄糖(11%)注射液非蛋白热卡占个体BMR比例,平均值为72.1%(S=8.9)。脂肪乳氨基酸(17)葡萄糖(11%)注射液配伍用药中加入氯化钾注射液的病例占63.0%,其中70.6%超推荐剂量;加入丙氨酰谷氨酰胺的病例为62.9%,用量全部超推荐剂量。结论:本院PN应用中营养风险评估基本缺失,合理的个体化方案制订水平与指南要求有较大差距,建议医院临床药师在PN应用方面加大相关监测评价等工作力度。 相似文献
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30.
《Clinics in plastic surgery》2015,42(1):115-121