The Growth Of The Fourth Cervical Vertebrae And C4-5 Intervertebral Disc In Fetus:Assessment By Postmortem MRI

Part I The Growth Pattern of C4 Vertebrae and Its Three Ossification Centers of Human fetus in Postmortem MRIObjectiveDetailed knowledge on the growth of normal fetal spine plays an important role in the prenatal diagnosis of congenital defects.This study focused on the age-specific parameters of vertebra C4 and its three ossification centers of normal fetuses ranged from 20 to 37 gestational ages(GA)using postmortem Magnetic Resonance Imaging(MRI).Materials and methodsWith the use of postmortem 3.0T MRI examinations,parameters' measurement and statistical analysis,the growth of each parameter of C4 vertebra and its three ossification centers were achieved in 41 normal human fetuses(21 males,20 females).ResultsThere was no significant difference in the gender or laterality.The height,cross-section area and volume of C4 vertebral body increased linearly as:y=0.099×GA+0.583(R2=0.852),y=2.994×GA-41.009(R2=0.959),y=14.894×GA-266.356(R2=0.96),respectively.The height,cross-section area and volume of the ossification center of the C4 vertebral body increased linearly as:y=0.079 X GA-0.137(R2=0.822),y=1.265×GA-16.342(R2=0.869),y=4.251×GA-76.965(R2=0.93),respectively.The cross-section area,length and height of the left neural ossification center increased linearly as:y=0.028×GA-0.476(R2=0.949),y=0.026×GA-0.079(R2=0.857),y=0.007×GA-0.043(R2=0.744);The cross-section area,length and height of the right neural ossification center increased linearly as:y=0.029×GA-0.497(R2=0.945);y=0.029×GA-0.146(R2=0.827),y=0.007×GA-0.047(R2=0.798);The ossification center-to-vertebral body volume ratio increased with gestational age between 20 and 30 GA,and declined gradually with gestational age after 30 GA.ConclusionThe morphometric parameters of vertebra C4 and its three ossification centers,being typical mid-cervical ones,show no gender or laterality difference.All the parameters grow linearly with GA.The age-specific reference intervals of vertebra C4 and its three ossification centers are very important in the prenatal diagnosis of congenital deformations of spine.Part ? The Growth Pattern of C4-5 Intervertebral Disc in Postmortem MRI and Histological Contrast of Human FetusObjectiveDetailed knowledge on the growth of normal fetal spine plays an important role in the prenatal diagnosis of congenital defects..This study focused on the age-specific parameters of the C4-5 intervertebral disc of normal fetuses ranged from 20 to 37 GA using postmortem Magnetic Resonance Imaging(MRI)as well as histological contrast.Materials and methodsWith the use of postmortem 3.0T MRI examinations,parameters' measurement and statistical analysis,the normal growth of each parameter of C4-5 intervertebral disc were achieved in 41 normal human fetuses(21 males,20 females).After being dissected,sliced and stained,histological images of C4-5 intervertebral disc were compared with MRI signals in relative section.ResultsThere was no significant difference in the gender of the fetuses.The height,cress-section area,length,width and volume of the C4-5 intervertebral disc increased linearly with GA as:y=0.039×GA-0.214(R2=0.544),y=1.929×GA-26.622(R2=0.813),y=0.248×GA-0.656(R2=0.793),y=0.153×GA-0.074(R2=0.686),y=2.776×GA-52.554(R2=0.762).During 20-35 gestational age,the disc height-to-vertebral height ratio increased with gestational age,and declined gradually with GA after 35 weeks.The histological appearance of C4-5 intervertebral disc was in correlation with MRI signal.ConclusionThe morphometric parameters of the C4-5 intervertebral disc,being typical mid-cervical one,show no gender difference.All the parameters grow linearly with gestational age.The age-specific reference intervals of the C4-5 intervertebral disc are very important in the prenatal diagnosis of congenital deformations of spine.The histological appearance of C4-5 intervertebral disc can be well-reflected in post-mortem MRI.