MRI study of normally developing fetal eyeball development in the second and third trimesters
10.3969/j.issn.1672-8467.2024.06.008
- VernacularTitle:孕中晚期正常发育胎儿眼球的MRI研究
- Author:
Li-Min XU
1
;
Guo-Fu ZHANG
;
Min-Hua SHEN
Author Information
1. 丽水市人民医院超声科 丽水 323050
- Keywords:
prenatal MRI;
foetus;
eye development;
the second and third trimester;
gestational age
- From:
Fudan University Journal of Medical Sciences
2024;51(6):931-938
- CountryChina
- Language:Chinese
-
Abstract:
Objective To analyze the correlation of eyeball diameters of normal fetuses with fetal gender and gestational age(GA)in the second and third trimesters,as well as the MRI morphological features of fetal eyeball,for providing reference for prenatal MRI diagnosis.Methods MRI data of fetuses who underwent prenatal MRI in Department of Radiology,Obstetrics and Gynecology Hospital,Fudan University from Mar 2014 to Jun 2020 were retrospectively analyzed.All fetuses had no abnormal findings in MRI and the subsequent ultrasound follow-up before birth.The left and right maximum transverse diameter of the eyeball(TDE),the upper-lower diameter of the eyeball(ULDE),and the anterior-posterior diameter of the eyeball(APDE)were measured in the transverse and sagittal T2-HASTE images(the maximum distance between the outer edges of the eye-rings),respectively.The correlation between the diameters and fetal gender was analyzed,as well as between the diameters and GA.Regression analyses were performed on the diameters and fetal age.MRI morphological features of fetal eyeballs in different GA in the second and third trimesters were observed,and the changing trends in TDE/APDE,TDE/ULDE and APDE/ULDE with the increasing GA were quantitatively analyzed.Results There were no significant differences between the left and right TDE,APDE and ULDE in normal fetuses in the second and third trimesters(t=0.198,-0.963,0.774,respectively),and none of them was related to fetal gender(r=-0.047,-0.040,-0.030,-0.022,-0.026 and-0.026,respectively).The left and right TDE,APDE and ULDE showed a highly linear increase with GA in the second and third trimesters(r=0.964,0.962,0.966,0.966,0.972,0.972,0.972,respectively,all P<0.001).The linear regression equations were as follows:left TDE(cm)=0.044×GA(wk)+0.368(R2=0.930),right TDE(cm)=0.045×GA(wk)+0.359(R2=0.926),left APDE(cm)=0.049×GA(wk)+0.078(R2=0.934),right APDE(cm)=0.049×GA(wk)+0.0073(R2=0.933),left ULDE(cm)=0.044×GA(wk)+0.242(R2=0.946),right ULDE(cm)=0.045×GA(wk)+0.237(R2=0.945).The fetal eyeballs transitioned from a conoidal shape in about the 20th week towards a more spherical geometry in about the 38th week.The TDE/APDE and TDE/ULDE decreased while APDE/ULDE increased with increasing GA.All of them gradually approached 1.0 in the third trimester,but the TDE was always the largest throughout the second and third trimesters.Conclusion The normal fetal eyeball development in the second and third trimesters demonstrates a symmetrical pattern and is gender-neutral.The TDE,APDE and ULDE linearly increased with GA and morphologically transitioned from a conoidal shape towards a more spherical geometry.
