年龄与颈动脉重塑：血管结构的三维超声定量研究

Age and carotid remodeling： a quantitative study of vascular structure with three dimensional ultrasound

目的应用三维容积超声成像技术定量分析不同年龄正常成年人颈动脉结构的变化，旨在探讨年龄对颈动脉血管重塑的影响规律。方法入选125例正常成年志愿者，依据年龄分为5组：A组，20～29岁，25例；B组，30～39岁，27例；C组，40～49岁，28例；D组，50～59岁，23例；E组，≥60岁，22例。应用超声三维容积探头获取双侧颈总动脉分叉处近心端长度为20mm的平直段血管容积数据，由血管斑块定量分析软件（vesselplaquequantificationsoftware，VPQ）进行脱机分析并自动获取内膜中层厚度（IMT）、血管总面积（VTA）、血管管壁面积（VwA）、血管管腔面积（VLA）及标化管壁指数（NWI），分析比较各年龄组间血管参数的差异。结果IMT、VTA、VwA、VLA和NWI与年龄显著正相关，相关系数r分别为0．79、0．48、0．77、0．27、0．67（P=0．00）。IMT、VTA和VwA随着年龄增加逐渐增大，各年龄组间差异有统计学意义（P〈0．01）；VLA只在E组显著增大，而NwI在D组与E组间差异无统计学意义。男性的VTA和VwA在A、B、c组显著大于女性，VLA在A、B组显著大于女性，三者在其他组别性别间差异无统计学意义，IMT和NWI在各组性别间差异均无统计学意义。结论年龄是颈动脉血管结构重塑的重要影响因素。随着年龄的增加，血管壁外向扩张和管壁增厚并存，导致血管总面积和管壁面积增大，但管腔面积在60岁以前却保持相对恒定。NwI在50岁以上各年龄组趋于稳定，且不受性别的影响，可作为评价50岁以上中老年人群血管负荷的定量参数。

Objective To investigate the vessel structure changes of carotid artery with age in normal adults with a newly-developed 3-dimensional ultrasound imaging modality. Methods One hundred and twenty-five normal adult volunteers were divided into five groups： group A, 20- 29 years old, 25 cases; group B,30 - 39 years old, 27 cases; group C, 40 - 49 years old, 28 cases; group D, 50 - 59 years old, 23 cases;group E, older than 60 years old, 22 cases. The straight sections of common carotid arteries were scanned by full-volume three-dimensional ultrasound probe. With a vessel plaque quantification software （VPQ）, the following parameters were obtained ： intima-media thickness （IMT）, vessel total area （VTA）, vessel lumen area （VLA）, vessel wall area （VWA）, and normalized wall index （NWI）. Results IMT, VTA,VWA,VLA and NWI were all positively correlated with age （r = 0.79,0.48,0.77,0.27 and 0.67 respectively, P = 0.00）,and there was significant difference among age groups （P 〈0.01）. IMT,VTA, VWA increased with age gradually whereas VLA increased only in group E and NWI showed no significant difference between group E and D. VWA and VTA of males were significantly greater than those of females in group A,B and C,and VLA of males was significantly greater than females in group A and B. There was no significant difference in IMT and NWI between gender groups. Conclusions Age is an important factor to carotid remodeling,and IMT,VTA and VWA increase with age,but VLA keeps constant in people under 60-year-old while NWI becomes stable in people over 50-year-old. It is essential to consider the physiological changes of carotid with age when pathophysiological process of atherosclerosis is involved.