A Research On The Ultrasonic Anatomy Specimen Making And Digitalized3D Rebuilding Of Fetal Heart

BackgroundIt is reported that0.8%to1.2%of newborn babies in China have congenital heartdisease, which means there are120,000-200,000congenital heart disease patients amongchildren each year. Among those, the rate of complicated cases, difficult-to-treat or earlydeath after birth with congenital heart disease is about20%, which means that it is one ofthe main causes of death for newborn babies and child. The ultrasound examination isalmost the only choice for prenatal imaging diagnosis of fetal cardiac malformations. Theobtaining and understanding of the normal standard section is the most essential conditionfor abnormal fetal heart diagnosis. In order to detect abnormal process, the sonographermust strictly conform to the cardiac ultrasound examination protocols and be familiar to thestandard section. Now there is no systematic report about the fetal cardiac anatomy teachingspecimens which is consistent with ultrasonic standard section. With the rapid developmentof digital medicine, digitized visible human organs plays an important role in thereconstruction of three-dimensional image, navigation of surgical and interventionalprocedures, preoperative virtual simulation and the telemedicine. The preparation anddigital three-dimensional reconstruction of fetal cardiac anatomy specimens will be ofbenefit to comprehensively understanding the complex fetal cardiac malformation from theinternal structure to the vascular malformation, consolidating the anatomical basis of thefetal heart, improving the integrity, fasting and accuracy of prenatal cardiac ultrasoundexamination. This study will promote the rapid, accurate and personalized development offetal echocardiography.ObjectiveIn view of the above-said issues, we have made both normal and complicatedcongenital malformed heart anatomy teaching specimens, which is in consistent with theultrasound standard section of the fetal, and completed the first complex cardiac fetal malformation body structure data collecting and digital three-dimensional reconstruction inChina. By collecting fetal heart ultrasound image data from some cases, we not onlyestablished a teaching resource combining theoretical and clinical teaching library, but alsoapplied it in teaching multi-level medical imaging professional students. All of these areaimed to help ultrasound professional beginners master the structure of normal orcomplicate deformities of the fetal heart, understand the characteristics of ultrasoundimaging, and improve the quality of fetal cardiac diagnosis.MethodA:Preparation of fetal cardiac ultrasonic teaching specimens:1. Establishing standard section of fetal echocardiography and collect the fetalechocardiography image files.2. Establishing standard section of fetales with complex congenital heart disease andcollect the fetal echocardiography image files.3. Collect the foramen ovale, atrium, main artery and speed of blood flow about20⁺⁰³9⁺⁶ weeks of robust fetal hear ultraphonic data.4. Preliminary processing and production of the specimen:10%formalin-fixed,opening the chest, freely remove the heart and record the blood vessel diameter and the sizeof the chamber, cut the hear with ultrasonic standard section according to the characteristicsof each of the specimens, keep image from different angle of the specimen, and put it incustomized plexiglass cylinder for archive retention.B: Digital three-dimensional reconstruction of a fetal heart and collection of fault dataset of continuous thin layer of a fetal heart:Specimen1with congenital heart malformations, fixed it with10%Formaldehyde,opening the chest, freely remove the heart, after that, fixe, dehydrate and paraffin-embedthe fetal heart and four human forearm veins, which have less branches and are straighter.Fixed the paraffin blocks on the slicer, thickness of10μm, HE staining, after pasting labelsand Shooting with Canon high-definition digital camera, collect the fetal heart imaging data.Sample2has been labored after been diagnosed with severe coarctation in one singleventricle, atrioventricular valve and the aorta by prenatal ultrasonography, weighting2650g.After being fixed in10%of formalin and went through64lines of CT scanning, it has beenembedded in5%of green gelatin and put into the-30℃icehouse for a week. Cut it from top to bottom layer by layer with a digital milling machine TK-6350in-25℃laboratory.Take pictures of the fetal layer by layer with a Canon high definition digital camera,obtaining its body model data and structural database. Fix and reconstruct the3D image ofthe anatomic structure of its heart, using a software named Amira.Results1. Preparation of a set of systemic ultrasound anatomic teaching sample of the fetalheart with consistent echocardiography sectionWe obtained standard incisal sections of6heart samples. The fetal cardiac anatomyteaching specimens are in consistent with ultrasonography section. With complete structure,no impairment of inner heart microstructure and the same structure and shape as in vivo,they’re able to meet the needs of theoretical and clinical practice teaching of fetal heart. Wereceived20fetal cardiac complex malformation teaching specimens, together with theirultrasonographic images. With1single ventricle,3double outlet right ventricles,3hypoplastic left hearts with aortic coarctation and interventricular septum deficiency,5oftetralogy of Fallot,1complete transposition of the great arteries,1hypoplastic right heartand1tricuspid valve with ventricular septal defect. The before labored ultrasonographicimages of these complex malformation fetal hearts, dissectional faulting profiles andcorresponding bulking teaching specimens were obtained at the same time.2. Fetal cardiac continuous lamina faulting dataset collection and digitalthree-dimensional reconstructionSample1: Obtain a set of continuous whole tissue sections of fetal hearts. Thestructure looks fine and complete. The color is fresh and bright after HE staining with nosign of breaking. Fetal hearts’ continuous slides are up to490sheets,10μm each. the imagefile for each layer size is about3.35MB, resolution2362×2362Pixel, totally1.641GBdatabase for the whole heart.Sample2: Fetal echocardiography image files and family informed consent donationpaper were selected before labored. CT and MRT tomoscan and fetal cardiac;reconstruction files were obtained from head to feet. Mill the fetal specimen continuously,0.2mm for each cross section,1495sections for the whole body. Digital photograph’sresolution is10989056pixels （4064×2704）. The image file sizes31.4MB each section and46.943GB for the whole data set, Together with the splitting images and gray level images of hearts and large vessels processed with Photoshop afterwards. Three-dimensional visibledataset for fetal hearts and large vessels were successfully reconstructed.Conclusion1. The parturition of the fetal heart in standard section anatomical specimens willallow beginners to master all parts of the anatomical structure of the fetal heart, tounderstand the characteristics of ultrasound imaging, to ensure that different checkers getsame check results, to reduce misdiagnosis, and to make the remote consultation,pathological teaching and understanding of abnormal anatomical structure more convenient.2. We have made abnormal heart anatomy teaching specimens, them can provide theanatomy basis in order the congenital heart disease being over cures way decision-makingbefore the diagnose and the surgery skill; Study of the iconography, anatomy andpathologic teaching provide resource to.3. The reconstruction of visible three-dimensional physiological fetal cardiac structurewill expand echocardiography teaching model and methods. Fetal cardiac three dimensionalvisible model can offer2D and3D anatomy comparison for echocardiogram, which alsohave a better man-machine interaction. It will help medical students identify obliquesectional anatomic structure of hearts and solve the problems faced by doctors: theechocardiogram oblique section cannot sharply match the slice dissection.