The MRI Study Of Changes Of Fetal Specimans Brain Volume And Signal Stength Befor And After Fixed

ObjectiveUsing a1.5T magnetic resonance imaging (MRI) to explore the fetal brain volume changes of samples of the signal strength after fixed, and the development of the fetal brain volume was analyzed to obtain the volume of fetal brain development law.Provide the basis for the study of fetal specimens of high-field MRI.Materials and MethodsCollected in October2012to April2014period, Shandong Province, East County People’s Hospital for a variety of reasons outside abortion fetal brain specimens of26cases of pregnancy gestational age of16weeks-39weeks, the mean gestational age26.19±6.89weeks.The first MR scans performed within12hours.And then use a10%formalin solution for specimens soaked. Respectively,24hours after the specimens fixed,72hours after the specimens fixed,7days after the specimens fixed,2weeks after the specimens fixed,4weeks after the specimens fixed go to brain MRI scan. The MR machines use Achieve1.5T superconducting scanner which made in Philips company in the Dutch.The scan sequence are DWI and T2WI, which DWI using echo planar sequence, b=0and1000s/mm2, diffusion direction is3, T2WI using TSE sequence scanning. DWI sequence slice thickness is3mm, the layer spacing is2mm, T2WI scans thickness is1mm, the interlayer spacing is0.5mm.After the image scanned,a professional post-processing software were used to measure the following data.1.Measuring the volume of each specimen fixed front and rear fixed at different times of the brain. 2.Measured for each specimen fixed at different times before and bilateral frontal white matter, basal ganglia, thalamus and apparent diffusion coefficient bilateral occipital white matter after bilateral fixed (ADC) values.Using professional statistical methods to analyze the results of measurements of the following aspects:1.A different variation of the fetus during pregnancy brain volumes.2.The variation of the fetal brain specimens fixed at different times before and after the volume.3. The variation of different gestation period of fetal brain apparent diffusion coefficient (ADC) values.4.A different variation of the diffusion coefficient concept timetable fixed fetal specimens before and after (ADC) values5.With or without statistical difference between the value of apparent diffusion coefficient (ADC) of the different parts of the fetal brain.6.With or without statistical difference between the value of apparent diffusion coefficient (ADC) of bilateral region of the fetal brain before fixed.Results1.There is a strong correlation between fetal brain volume and gestational age. There are17weeks gestational age16when thoughtful increased slightly from17to24weeks is relatively stable, rising from25to28weeks straight, significantly increase leveled off after30weeks.2.After the specimens fixed using10%formalin, the brain volume did not change. However, with the extension of the fixed time, the specimen showed sulci gradually become unclear.3.Before the specimens were fixed, left frontal and right frontal, ADC value difference left basal ganglia and right basal ganglia, thalamus and the left and right thalamus, left occipital lobe and right occipital lobe was not significant between statistical significance, P>0.05.4.Before the specimens were fixed, left frontal and left occipital lobe, ACD value differences left basal ganglia and left thalamus was no significant statistical significance, left frontal and left basal ganglia, left frontal and left thalamus, left occipital lobe and left basal ganglia differences left occipital lobe and the left thalamus was significant statistically significant.5. The ADC value of the left frontal white matter does not have obvious correlation with the gestational age.The ADC value of the left basal ganglia, left thalamus, left occipital lobe white matter have obviously negative correlation with pregnant weeks.In other words,with the gestational age increased, the ADC values decreased.6.The use of formalin-fixed specimens after three days after fixation of the left frontal lobe ADC values decreased slightly, then straight up, increase significantly; ADC value is fixed on the left after1week significantly increased basal ganglia, followed by a rapid decline; ADC values in the left thalamus fixed after no special laws; fixed three days after the ADC values of the left occipital slight decline, then straight up, increase significantly.ConclusionThe results of this study show that:1.5T magnetic resonance imaging (MRI) can be a good indication of specimens anatomical information, be able to evaluate the clinical diagnosis and treatment of diseases related to abnormal fetal brain development to provide morphological basis. In order to obtain a better, consistent with the fetal development of image information, MRI scans should be performed as soon as possible after the fetus specimens obtained.