代谢综合征患者腹内脂肪与心血管损害的关系

目的分析代谢综合征(MS)患者腹部脂肪分布及与心血管损害的关系。方法108例住院患者分为MS组(70例),高血压组(EH,22例),2型糖尿病组(T2DM,16例),计算三组腹内脂肪面积(VA)、腹壁脂肪面积(SA)及VA/SA,并分析它们与左室重量(LVM)、左室重量指数(LVMI)、颈动脉内膜中层厚度(IMT)、心肌缺血的关系。结果MS组患者较EH组和T2DM组VA显著增高(115·69±48·72cm2vs69·96±25·41cm2、55·96±29·75cm2,P均<0·01),VA≥80cm2组较VA<80cm2组LVM、LVMI均明显升高(186±70gvs155±44g,51±17g/m2vs44±13g/m2,P均<0·05),VA/SA≥0·75组较VA/SA<0·75组左、右侧IMT均明显增厚(0·90±0·41mmvs0·75±0·21mm,0·89±0·32mmvs0·77±0·21mm,P均<0·05),VA≥100cm2组心肌缺血率和缺血程度明显高于VA<100cm2组(P<0·05)。收缩压、舒张压、VA导致IMT增厚的OR值有显著意义。结论代谢综合征时腹内脂肪明显堆积,其堆积的程度与心血管损害的程度密切相关,且腹内脂肪是心血管损害的独立影响因素。     

DSCT测量心外膜脂肪体积与代谢综合征组分的相关性研究

目的:探讨使用双源CT(DSCT)测量心外膜脂肪(EAT)体积与代谢综合征(MS)各组分指标的相关性.方法:根据国际糖尿病联盟(IDF)标准,将171例住院患者分为非MS组和MS组,记录患者的临床相关指标,包括性别、年龄、体质量指数(BMI)、腰围、血压、血糖和血脂指标(甘油三酯、总胆固醇、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇).所有患者使用DSCT行冠状动脉钙化积分(CACS)扫描,在CACS图像上测量EAT的体积,对EAT体积与MS组份指标的相关性进行统计学分析.结果:男性受试者中MS组的EAT体积[(147.10±45.22)cm3]明显高于非MS组[(100.37±83.42)cm3],差异有统计学意义(P＜0.001);而女性受试者中,MS组与非MS组间EAT体积的差异无统计学意义(P=0.089).Spearman等级相关分析显示,男性组EAT体积与MS组分指标的数目呈等级相关(r=0.399,P＜0.001);而女性组EAT体积与MS组分指标的数目无相关性(P=0.870).结论:EAT体积与男性MS发生关系密切,男性EAT体积反映了MS组分的聚类效应,可作为评估MS的一个非创伤性重要指标.     

尿酸代谢与腹型肥胖及代谢综合征的相关性研究

目的 探讨心血管疾病的高危患者尿酸(UA)水平的变化与腹型肥胖及代谢综合征(MS)的相关关系.方法 选取2002年1月-2006年12月第三军医大学大坪医院住院的1 553例UA正常的心血管疾病高危患者,其中男性782例,女性771例,年龄56.20±12.85(20～80)岁.所有患者均测量收缩压(SBP)、舒张压(DBP)、腰围(WC),并检测空腹血糖(FPG)、血浆总胆固醇(TC)、甘油三酯(T℃)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)及UA水平.部分患者在空腹状态下行腹部CT扫描,测量腹内脂肪面积(VA)和皮下脂肪面积(SA).根据检测结果分析UA水平与腹型肥胖及MS的相关关系.结果 MS检出率为51. 38%(798/1 553),MS组与非MS组UA水平无显著差异(P>0.05).腹型肥胖检出率为50.23%(780/1 553),肥胖组UA水平明显高于非肥胖组(P<0.01).随着WC的增加,UA水平随之升高(P<0.01).随着UA水平增加,MS及腹型肥胖检出率增加,肥胖的相关参数中腹内脂肪面积(VA)值也随之增加(P<0.01).Logistic回归分析显示,UA是MS和腹型肥胖的独立危险因素.结论 心血管疾病的高危患者中,腹型肥胖者的UA水平高于非肥胖者.UA是心血管疾病的高危患者合并MS及腹型肥胖的独立危险因素,随着UA水平的升高,其发生MS及腹型肥胖的风险均显著增加.     

冠状动脉周围脂肪密度指数与代谢综合征组分及斑块参数关系分析

目的 探讨冠状动脉斑块周围脂肪密度指数(FAI)与代谢综合征(MS)相关组分及斑块参数间的关系。方法 回顾性搜集2020年1月至12月连云港市第一人民医院147例因胸痛或胸部不适行冠状动脉CT造影(CCTA)患者的资料，其中男100例，女47例，年龄27～88岁，平均(62.08±10.78)岁，所有患者均接受CCTA及一个月内的冠状动脉数字减影血管造影(DSA)检查。定量资料测量包括斑块周围FAI、钙化积分、心外膜脂肪组织(ECAT)密度及体积，定性资料测量包括斑块类型、血管分布、狭窄程度等。根据MS诊断指南搜集患者相关临床指标(如血糖、血脂、身高、体重等)。以斑块周围FAI值是否≥-70 HU,将患者和斑块分为FAI阳性组(52例)与FAI阴性组(95例),分析比较两组间年龄、性别、斑块性质、血管分布、狭窄程度、MS相关组分等指标之间的关系。结果 FAI阴性组在MS组分个数之间无统计学差异(F值=1.354,P值=0.256),FAI阳性组在MS组分个数间有统计学差异(F值=5.049,P值=0.002)。FAI阳性组及FAI阴性组在斑块类型有统计学差异(χ²...     

代谢综合征与脑白质病变关系研究

目的：探讨代谢综合征及其各组分与脑白质病变的关系。方法：收集整理本院门诊相关资料完整的中老年患者290例,分别记录其高血压、糖尿病或高脂血症病史,并进行腹围测量;入选病例均复习头颅CT和（或）MRI片。结果：符合代谢综合征诊断者147例,占50.7%,其中检出脑白质病变111例,占75.5%;高血压、血脂异常、糖尿病及腹围超标与脑白质病变均显著相关。结论：代谢综合征与脑白质病变发生显著相关,各组分均为脑白质病变的独立影响因素。     

中老年高尿酸血症与代谢综合征关系的研究

目的探讨中老年人群高尿酸血症(uric acid UA)相关因素,及高UA血症与代谢综合征(metabolic syndrome MS)之间的关系及其临床测定意义。方法选取2008年5月—2009年5月在本院干部病房门诊体检与治疗的患者,筛选出225例高UA血症及216例正常UA组,比较两组一般临床资料、生化特点及MS组分分布情况,分析高UA组的相关危险因素。结果高UA组与MS中的血压、血糖、血脂等呈正相关(P<0.05),高UA组的MS患病率明显高于对照组。结论高UA血症与MS中的诸多因素相关,提示发生心脑血管病的危险性增加。     

老年男性代谢综合征特点及与代谢相关疾病的关系

目的 探讨老年代谢综合征（MS）的特点及与代谢相关疾病关系.方法 回顾性分析我院住院及体检的军队离退休干部健康资料4601例,根据有无MS分为MS组（1656例）和对照组（2945例）,对两组MS指标及疾病进行比较.结果 本组MS的患病率为35.99%;与对照组比较,MS组体重指数、收缩压、空腹血糖、LDH-C、TG明显升高;MS组肥胖症、高血压病、糖尿病、冠心病等发病率较对照组明显升高;MS组前列腺增生患者的下尿路症状更重,上述差异都有统计学意义（P＜0.05）.结论 MS是老年人常见合并症之一,是促进老年代谢相关疾病发生、发展的原因之一.认识和管理好MS,对提高老年人生活质量有重要意义.     

飞行人员代谢综合征与动脉粥样硬化危险因素研究

目的 调查飞行人员代谢综合征(MS)患病率,探讨其发病机制并提出防治策略要点.方法 606例飞行人员为调查对象做断面研究,测量体质指数(BMI)、收缩压(SBP)、舒张压(DBP)、胸围、腰围和臀围.空腹采集静脉血测定甘油三酯(TG)、总胆同醇(TC)、高密度脂蛋白-胆固醇(HDL-C)、空腹血糖(FBG)、血尿酸(PUA)、碱性磷酸酶(ALP)、γ-转肽酶(GGT)和丙氨酸转氨酶(ALT).MS诊断标准:BMI≥25或腰围≥85 cm为肥胖;SBP≥130 mm Hg或(和)DBP≥85 mm Hg为高血压;FBG≥6.10 mmol/L为空腹血糖受损(IFG);TG≥1.70 mmol/L为高TG血症;HDL-C<0.91 mmol/L为低HDL-C血症.上述5项中有任意3项或3项以上者诊断为MS.结果 飞行人员MS检出率为3.80%.MS有3个组分者20例(86.96%);有4个组分者3例(13.04%),以3个组分异常多见.MS组分中:肥胖23例(100%);高TG血症22例(95.65%);低HDL-C血症11例(47.83%);高DBP 9例(31.13%),高SBP 5例(21.74%);IFG 6例(26.09%).MS与非MS两组间比较:BMI、腰围、SBP、DBP、FBG、HDL-C和TG均值水平差异有显著性意义(P<0.01);TC水平、胸围、臀围、吸烟年限及每口吸烟景,均值差异有显著性意义(P<0.01);总飞行时间和年龄,牛化参数GGT、ALP、PUA、ALT均值水平差异有显著性意义(P<0.05或P<0.01).多元逐步回归分析显示烟龄、ALT、PUA 3个变量进入回归方程(P<0.01或P<0.05),烟龄、ALT、PUA水平与MS独立相关. 结论 我军飞行人员MS检出率较低.肥胖和高TG血症是我军飞行人员MS的主要特点.提高对MS的知晓率、控制体重、合理膳食是首要防治策略.     

代谢综合征与脑卒中

代谢综合征是一组人体代谢异常的集合体,根据美国国家胆固醇教育计划成人治疗组（NCEP-ATPⅢ）的定义,代谢综合征应至少具有以下异常中的3种,即中心性肥胖、糖代谢异常、脂代谢异常及血压升高等。现代医学证明,代谢综合征是遗传和环境因素共同作用的结果,胰岛素抵抗是代谢综合征发病的中心环节,肥胖特别是中心性肥胖是胰岛素抵抗的重要危险因素。脑卒中是脑血管病的统称,包括脑出血、脑梗死、短暂性脑缺血发作及蛛网膜下隙出血等,病因包括颅内动脉硬化、动静脉畸形、动静脉瘘、动脉瘤及脑肿瘤等。目前,脑卒中不仅是死亡的首要原因,也是致残的主要原因。     

Comparison of visceral adipose tissue quantification on water suppressed and nonwater-suppressed MRI at 3.0 Tesla

Purpose:

To systematically evaluate and compare the performance of water‐saturated and nonwater‐saturated T1‐weighted 3.0 T magnetic resonance imaging (MRI) in the application of visceral adipose tissue (VAT) quantification.

Materials and Methods:

Forty‐five patients underwent abdomen MRI using two different sequences at 3.0 T: 1) a traditional T1‐weighted gradient echo sequence, and 2) the same sequence with water presaturation to enhance fat and nonfat contrast. VAT amounts from both water‐saturated and nonwater‐saturated images were quantified with a manual thresholding technique and an automated segmentation method to study quantification variability and consistency of the two imaging techniques.

Results:

Nonwater‐saturated MRI had significantly larger coefficient of variation than water‐saturated MRI in the imaging reproducibility study based on 112 slices from seven subjects (11.4% vs. 2.5%, P < 0.0001). VAT volumes measured from the nonwater‐saturation MRI sequence had significantly higher variability than those from water‐saturation images even when using a manual quantification method based on images from 38 subjects (1.76% vs. 1.08%, P < 0.001). In addition, the VAT volume amounts from nonwater‐saturation images and water‐saturated images quantified with the automatic and manual quantification methods were statistically consistent.

Conclusion:

Water‐saturated MRI sequences at 3.0 T for VAT quantification improve reproducibility and decrease variability compared with nonwater saturated sequences, especially with the use of automatic quantification methods. J. Magn. Reson. Imaging 2012;35:1445–1452. © 2012 Wiley Periodicals, Inc.     

Impact of partial volume effects on visceral adipose tissue quantification using MRI

Purpose:

To quantitatively estimate the impact of partial volume effects on visceral adipose tissue (VAT) quantification using typical resolution magnetic resonance imaging (MRI).

Materials and Methods:

Nine normal or overweight subjects were scanned at central abdomen levels with a water‐saturated, balanced steady‐state free precession (b‐SSFP) sequence. The water‐saturation effectiveness was evaluated with region‐of‐interest analysis on fat, muscle, bowel, and noise areas. The number of full‐volume (FV) and partial‐volume (PV) fat pixels was estimated based on a gray‐level histogram model of water‐saturated images. Both FV and PV fat amounts were quantified.

Results:

High‐quality, fat‐only images were generated with the b‐SSFP imaging method. Fat SNR was 77.7 ± 25.6 and water‐saturation was effective, with the average fat‐to‐water signal intensity ratio = 20.7 ± 3.8. The average ratio of partial‐ to full‐volume fat amounts was 104.0%. The ratio was higher with lower body mass index (BMI) and PV fat amount only increased slightly when BMI increased.

Conclusion:

PV fat contributes a significant amount of fat to fat measurements on typical spatial resolution MRI on normal and overweight subjects. The relative PV fat contribution is markedly higher in slimmer patients. Inclusion of this portion of the adipose tissue will increase overall accuracy and decrease variability of VAT quantification using MRI. J. Magn. Reson. Imaging 2011;. © 2011 Wiley Periodicals, Inc.     

Automated method for accurate abdominal fat quantification on water-saturated magnetic resonance images

PURPOSE: To introduce and evaluate the performance of an automated fat quantification method for water-saturated magnetic resonance images. MATERIALS AND METHODS: A fat distribution model is proposed for fat quantification on water saturated magnetic resonance images. Fat from both full- and partial-volume voxels are accounted for in this model based on image intensity histogram analysis. An automated threshold method is therefore proposed to accurately quantify total fat. This method is compared to a traditional full-volume-fat-only method in phantom and human studies. In the phantom study, fat quantification was performed on MR images obtained from a human abdomen oil phantom and was compared with the true oil volumes. In the human study, results of the two fat quantification methods of six subjects were compared on abdominal images with different spatial resolutions. RESULTS: In the phantom study, the proposed method provided significantly more accurate estimations of true oil volumes compared to the reference method (P < 0.0001). In human studies, fat quantification using the proposed method gave much more consistent results on images with different spatial resolutions, and on regions with different degrees of partial volume averaging. CONCLUSION: The proposed automated method is simple, rapid, and accurate for fat quantification on water-saturated MR images.     

Compensation of RF field and receiver coil induced inhomogeneity effects in abdominal MR images by a priori knowledge on the human adipose tissue distribution

Purpose:

To reliably compensate bias field effects in abdominal areas to accurately quantify visceral adipose tissue using standard T1‐weighted sequences on MR scanners with up to 3 Tesla (T) field strength.

Materials and Methods:

Compensation is achieved in two steps: The bias field is first estimated by picking and fitting sampling points from the subcutaneous adipose tissue, using active contours and a thin plate fitting spline. Then, additional sampling points from visceral adipose tissue compartments are detected by thresholding and the bias field estimation is refined. It was compared with an established method using a simulated abdominal image and real 3T data.

Results:

At low bias field amplitudes (40–50%), the simulation study showed a good reduction of the mean coefficients of variance (CV) for both approaches (>80%). At higher amplitudes, the CV reduction was significantly higher for our approach (83.6%), compared with LEMS (54.3%). In the real data study, our approach showed reliable reduction of the inhomogeneities, while the LEMS algorithm sometimes even amplified the inhomogeneities.

Conclusion:

The proposed method enables accurate and reliable segmentation of abdominal adipose tissue using simple thresholding techniques, even in severely corrupted images slices, obtained when using high field strengths and/or phased‐array coils. J. Magn. Reson. Imaging 2011;. © 2011 Wiley‐Liss, Inc.     

Automatic segmentation of intra‐abdominal and subcutaneous adipose tissue in 3D whole mouse MRI

Purpose

To fully automate intra‐abdominal (IAT) and total adipose tissue (TAT) segmentation in mice to replace tedious and subjective manual segmentation.

Materials and Methods

A novel transform codes each voxel with the radius of the narrowest passage on the widest possible three‐dimensional (3D) path to any voxel in the target object to select appropriate IAT seed points. Then competitive region growing is performed on a distance transform of the fat mask such that competing classes meet at narrow passages effectively segmenting the IAT and subcutaneous adipose compartments. Fully automatic segmentations were conducted on 32 3D mouse images independent to those used for algorithm development.

Results

Automatic processing worked on all 32 images and took 28 s on a 3.6 GHz Pentium computer with 2.0 GB RAM. Manual segmentation by an experienced operator typically took 1 h per 3D image. The correlation coefficients between manual and automated segmentation of TAT and IAT were 0.97 and 0.94, respectively.

Conclusion

The fully automatic method correlates well with manual segmentation and dramatically speeds up segmentation allowing MRI to be used in the anti‐obesity drug discovery pipeline. J. Magn. Reson. Imaging 2009;30:554–560. © 2009 Wiley‐Liss, Inc.     

Novel segmentation method for abdominal fat quantification by MRI

Purpose:

To introduce and describe the feasibility of a novel method for abdominal fat segmentation on both water‐saturated and non–water‐saturated MR images with improved absolute fat tissue quantification.

Materials and Methods:

A general fat distribution model which fits both water‐saturated (WS) and non–water‐saturated (NWS) MR images based on image gray‐level histogram is first proposed. Next, a novel fuzzy c‐means clustering step followed by a simple thresholding is proposed to achieve automated and accurate abdominal quantification taking into consideration the partial‐volume effects (PVE) in abdominal MR images. Eleven subjects were scanned at central abdomen levels with both WS and NWS MRI techniques. Synthesized “noisy” NWS (nNWS) images were also generated to study the impact of reduced SNR on fat quantification using the novel approach. The visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) amounts of the WS MR images were quantified with a traditional intensity thresholding method as a reference to evaluate the performance of the novel method on WS, NWS, and nNWS MR images.

Results:

The novel approach resulted in consistent SAT and VAT amounts for WS, NWS, and nNWS images. Automatic segmentation and incorporation of spatial information during segmentation improved speed and accuracy. These results were in good agreement with those from the WS images quantified with a traditional intensity thresholding method and accounted for PVE contributions.

Conclusion:

The proposed method using a novel fuzzy c‐means clustering method followed by thresholding can achieve consistent quantitative results on both WS and NWS abdominal MR images while accounting for PVE contributing inaccuracies. J. Magn. Reson. Imaging 2011;. © 2011 Wiley‐Liss, Inc.