CT体脂分布与颈动脉斑块特征的相关性研究

Correlation of Adipose Tissue Distribution Evaluated by CT and Characteristics of Carotid Plaque

目的分析CT体脂分布与颈动脉粥样硬化斑块负荷、斑块稳定性的关系。方法回顾性分析122例患者的临床及影像学资料,所有患者均于2周内行腹部CT和头颈CTA检查。将腹部CT原始数据上传至GE AW 4.7工作站,分别在后处理工作站上测量平脐水平腹部内脏脂肪面积(VFA)、皮下脂肪面积(SFA),计算内脏脂肪面积/皮下脂肪面积比值(VFA/SFA)。基于头颈部CT血管成像评估颈动脉斑块类型和狭窄程度。依据颈动脉斑块类型将患者分为稳定斑块组、不稳定斑块组;依据颈动脉狭窄程度将患者分为无/轻度狭窄组、中/重度狭窄组。分别比较临床实验室指标、腹部脂肪定量参数在两组间的差异。采用SPSS 21.0统计学软件进行数据处理。符合正态分布的计量资料,两组间比较采用t检验;非正态分布的计量资料,两组间比较采用Mann-Whitney U检验。计数资料采用χ^(2)检验。以P<0.05为差异有统计学意义。结果VFA/SFA比值在不稳定斑块组高于稳定斑块组,两组间差异具有统计学意义(P=0.039);VFA、SFA在两组间差异无统计学意义(P=0.116、0.695);总胆固醇在不稳定斑块组低于稳定斑块组,差异具有统计学意义(P=0.041)。中/重度狭窄组患者冠心病发病率高于无/轻度狭窄组患者,两组间差异具有统计学意义(P=0.026);CT体脂分布定量参数(VFA、SFA、VFA/SFA比值)在无/轻度狭窄组、中/重度狭窄组间差异均无统计学意义(P值均>0.05)。结论腹部脂肪定量参数VFA/SFA比值与颈动脉斑块稳定性密切相关,VFA/SFA比值越高,斑块稳定性越差。

Objective To investigate the relationship between adipose tissue distribution evaluated by CT and burden or composition of carotid atherosclerotic plaque.Methods The clinical and imaging data of 122 patients were retrospectively evaluated.All patients underwent abdominal CT and head neck computer tomography angiography(CTA),and the time interval of two examinations was less than two weeks.All images of original abdominal CT were uploaded to GE AW4.7 workstation.Visceral fat area(VFA)and subcutaneous fat area(SFA)were measured at umbilical level on workstation by one radiologist.The ratio of visceral to subcutaneous fat area(VFA/SFA)was calculated according to the results of VFA and SFA.Carotid plaque type and artery stenosis were evaluated using CTA.According to the carotid plaque type,the patients were divided into two groups including stable plaque group and vulnerable plaque group.According to the carotid artery stenosis,the patients were also divided into non/mild stenosis group and moderate/severe group.The differences of clinical characteristics and quantitative parameters of abdominal adipose tissue were separately compared between the two different groups.SPSS 21.0 version was used for statistical analysis.The t-test was used for comparison of measurement data following the normal distribution,while Mann-Whitney U test was used for measurement data not following the normal distribution.Chi-square test was used to compare the count data.Probability(P)value<0.05 was considered statistically significant.Results VFA/SFA of vulnerable plaque group was higher than that of stable plaque group(P=0.039).Nevertheless,there was no significant difference between VFA and SFA(P=0.116、0.695).Compared to the stable plaque group,lower total cholesterol was observed in the vulnerable plaque group(P=0.041).Patients in the moderate/severe group showed higher incidence of coronary heart disease compared to the non/mild stenosis group(P=0.026).The CT quantitative parameters of adipose tissue(VFA,SFA and VFA/SFA)had no significant differences between non/mild stenosis group and moderate/severe group(P>0.05).Conclusion The CT quantitative parameters of abdominal adipose tissue(VFA/SFA)were closely related to the stability of carotid plaque.The higher the VFA/SFA ratio,the worse the stability of carotid plaque.