The Research Of 3D-Reconstruction In Kidneys Of Mice With High-Frequency Micro-Ultrasound

B ultrasound is widely used in clinical examination, with the advantage of non-invasive, wide application, easy and flexible, secure and low cost,especially in the department of urology, which can help doctors in the diagnosis of kidney,urinary,bladder or prostate disease and even becomes the first selection of examination in urology.However,regular B ultrasound examination has much clinical limitation.For example,it can't reflect the three-dimention shape of organs directly. Although three-dimention ultrasound examinations have advented,but for many reasons,they don't applicate in clinic. And there is very little research of the three dimentional reconstruction of B ultrasound.This research will study from the establishment of technical process of three-dimentional reconstruction of high-frequency micro-ultrasound in mice to follow ing up the growth of kidney and ureter in mice for wondering w.hether the high-frequency micro-ultrasound can examinate,reconstruct and measure the normal or hydro kidney,laying the foundation of the further study.Part I The establishment of technical process for imaging the kidney of mice with high-frequency micro-ultrasoundObjective:Establish the technical process of imaging the kidney of mice with the Vevo 770 UBM ultrasound scanning system through the preliminary experiment and to be familiar with how to anesthesia the mice safely in the process of examination.Method:Five normal newborn C57BL/6 mice are used in our preliminary experiment. We scan the bilateral kidney of each mouse in the first day after the birthday,one-week old,two-week old,three week old and six-to-eight-week old with Vevo 770 UBM ultrasound system. And then we compare the volume of reconstructed kidney with the volume of mice's kidney measured by micro CT in using of SPSS 15.0 for indepent t test for two indenpent samples.Our purpose is to realize the accuracy and compare the advantage and disadvantage of the high-frequency micro-ultrasound reconstructing method with classical micro CT method and overflow method,which could tell us the prospective application in clinic of our method.Results:None of the five mice is dead from anesthesia accidents or improper operation from its birthday to the end of examination in 8-week old. And each time after the experiment,the mouse can be accepted by its mother to get fed without any related complications.There are 10 reconstructed kidneys in five mice in the preliminary experiment.The volume of them is listed in Table 1.Its average volume is 183.18±30.90mm3.We compare the average that we reconstructed with the average,which is looked up in the paper using the method of micro CT,by SPSS 15.0 for indepent t test for two indenpent samples(p=0.817>0.05).Conclusion:1.There is no significant statistical difference showed in the method of high-frequency micro-ultrasound 3D reconstruction and micro CT 3D reconstruction.The accuracy of our method is good.2.The method of high-frequency micro-ultrasound shows the advantages of high safety and repeatability,low dosage of radiation,accuracy,non-invasion,convenience,low cost,rapid availability and impersonality.It also shows the disadvantages including high requirement of technical staff,unsharpness in the upper and lower pole of the kidney,interference in the examination process easy fatigue in technical staff and so on.But overall,compared to micro CT and overflow method,the advantage of high-frequency micro-ultrasound method is obviously.And we also believe that we will conquer the disadvantage with the progress of technique.Part II Follow up the development of kidneys of mice by using high-frequency micro-ultrasound reconstructionObjective:We follow up the development of kidneys in newborn mouse model of CAKUT(congenital anomalies of kidney and urinary tract) using the technical process we establish in the Part I.Our purpose is to consummate the technique in the scanning of hydro-kidney and lay the foundation of further study to the relationship between function and volume of renal parenchyma simultaneously.Method:We have selected four pairs of C57BL/6 mice which are knocked out the ROBO 2 gene and let them generate newborn mice seperately to establish the normal and hydro mouse model. And follow up the development of kidneys of newborn mice using the technical process in the Part I.We enroll the mice which are older than two-week old and cut their tail to sequence their type of ROBO 2 gene to study the relationship between genotype with phenotype.Simultaneously we use SPSS 15.0 software to compare the normal kidneys and pelvis with them of hydro-mice by independent t test for two independent samples and depict the box map of development of kidneys and pelvis in two groups to realize the rules and characteristics of their development. We will show the 3D pictures of kidneys and pelvis in the development of mice.Results:Finally,a total of three hydro-mice and eight normal mice survived for more than 3-week old.The data of their volume of kidney and pelvis is listed in the Table 2. The genotype and phenotype of the mice are consistent with that in theory.There are significant statistical differences in volume of kidney between the normal mice and hydro-mice except that when they are two-week old.Otherwise,the volume of pelvis is significant statistically difference in them on each time of the examination. We also show the 3D pictures and saggital image of the developing process of the normal kidney and pelvis of mice in this part.Coclusion:1.In the process of 3D reconstruction,there is no obvious differences in the technique between normal kidney and hydro-kidney,except the image display in the B-ultrasonography.2. About the reason of differences in the volume of kidneys bitween normal mice and hydro-mice,we think it could be relative with less amount of the samples,otherwise,all of the severe hydro-mice are dead before the time of two-week-old,so the enrolled mice's diseases are mild or moderate.3.From the box map of the development of mice's kidneys,we can realize that the average volume of pelvis in two-week-old normal mice is larger than that of three-week-old normal mice.But the difference is not obvious.We think it is also caused by the less amount of samples and the inevitable error. And no matter they are normal mice or hydro-mice,their volume of pelvis' development are a little slower in two to three weeks age.