孕中晚期胎儿脑室与后颅窝池的生长发育随孕周变化的规律:磁共振成像定量研究

Fetal ventricles and posterior cranial fossa development in second and third trimesters and their variations with gestational age: a quantitative MRI study

目的:采用MRI成像定量分析孕中晚期脑室与后颅窝池生长发育随孕周的变化规律。方法:本研究为回顾性研究。研究对象为2016年1月至2020年1月在广州医科大学附属第三医院行产前MRI检查的孕妇675例,MRI检查时平均孕周为(29.0±8.5)周。获取这些研究对象的MRI资料,分析左侧脑室三角区宽度(left lateral ventricle trigonometric width,LLVTW)、右侧脑室三角区宽度(right lateral ventricle trigonometric width,RLVTW)、第三脑室宽度(third ventricle width,TVW)、第四脑室宽度(fourth ventricle width,FVW)、第四脑室前后径(anterior posterior diameter of the fourth ventricle,APDFV)、透明隔间腔宽度(cavum septum pellucidum width,CSPW)和小脑延髓池宽度(cisterna magna width,CMW)等数据。采用t检验、Spearman相关性分析和Pearson相关性分析等方法对数据进行统计学分析。结果:(1)共675例胎儿纳入本研究,不同性别胎儿的检查孕周差异无统计学意义。(2)女性胎儿(392例)的TVW、CMW明显低于男性胎儿(283例)[(0.60±0.05)与(0.63±0.04)cm,t=-5.059;(0.57±0.14)与(0.67±0.15)cm,t=-7.445;P值均<0.001]。TVW、CMW与胎儿性别呈明显负相关(r值分别为-0.179和-0.312,P值均<0.001)。(3)LLVTW、RLVTW、TVW、FVW、APDFV、CSPW和CMW均与胎龄呈正相关(r值分别为0.310、0.267、0.205、0.801、0.829、0.216和0.284,P值均<0.05),其中FVW、APDFV与胎龄呈显著线性相关(r值分别为0.801和0.829,P值均<0.001)。(4)LLVTW、RLVTW在孕中期变化不明显,在孕晚期轻微增长;在孕中晚期TVW分布较离散,在孕26~<28周前随胎龄增加略有增长;FVW、APDFV在孕中晚期随胎龄增加呈线性增长;CSPW在孕中晚期随胎龄增加缓慢增长;CMW在孕中期随胎龄增加略有增长,孕晚期变化较小。结论:孕中晚期胎儿脑室及后颅窝池生长发育随着胎龄的增加呈现不同程度的增长趋势,其中TVW、CMW与胎儿性别呈明显负相关。

Objective To investigate the normal range of fetal ventricles and posterior cranial fossa development in the second and third trimesters and their variations with gestational age using quantitative MRI analysis.Methods This retrospective study enrolled 675 pregnant women who underwent prenatal MRI examination with an average gestational week of 29.0±8.5 in the Third Affiliated Hospital of Guangzhou Medical University from January 2016 to January 2020.MRI data of all the subjects were collected and analyzed,including left lateral ventricle trigonometric width(LLVTW)and right lateral ventricle trigonometric width(RLVTW),third ventricle width(TVW),fourth ventricle width(FVW),the anterior-posterior diameter of the fourth ventricle(APDFV),cavum septum pellucidum width(CSPW),cisterna magna width(CMW),etc.Spearman,Pearson correlation analysis,and t-test were used for the statistical analysis.Results(1)Totally 675 fetuses were recruited,including 392 female and 283 male fetuses.No statistical difference of gestational weeks at MRI was found between male and female fetuses.(2)The mean value of TVW and CMW of the female fetuses were significantly higher than those of male fetuses[(0.60±0.05)vs(0.63±0.04)cm,t=-5.059;(0.57±0.14)vs(0.67±0.15)cm,t=-7.445;both P<0.001].Spearman correlation analysis showed that TVW and CMW were negatively correlated with fetal gender(r=-0.179 and-0.312,both P<0.001).(3)Pearson correlation analysis showed that LLVTW,RLVTW,TVW,FVW,APDFV,CSPW,and CMW were all positively correlated with gestational weeks(r=0.310,0.267,0.205,0.801,0.829,0.216 and 0.284,all P<0.001).FVW and APDFV were significantly linearly correlated with gestational weeks(r=0.801 and 0.829,both P<0.001).(4)There was no significant change in LLVTW and RLVTW in the second trimester,but a slight increase was found in the third trimester.TVW showed a scattered distribution in the second and third trimesters and increased slightly with the gestational week at 26 to 27+6 gestational weeks.FVW and APDFV increased linearly while.CSPW increased slowly with gestational weeks in the second and third trimesters.CMW increased slightly with gestational weeks in the second and third trimesters but showed little change in the third trimester.Conclusions The development of fetal ventricles and posterior cranial fossa in the second and third trimesters show a growth trend of varying degrees with the increase of gestational weeks.TVW and CMW are significantly negatively correlated with the fetal gender.