A Research On Application Of Three Dimensional Simulation Entity Skull Model In Cranioplasty In Children With Macrocephaly

【research background】The technology of computer image processing is fleetly developingand widely applied in clinical medicine. In the respect ofcomputer-assisted operation, its technology mainly includes bothcyber-virtual model and cyber three dimensional simulation entity model,two respects. The technology of cyber-virtual model and actual modelcan be mutual complementation in surgical planning and application. Thevisualisation of virtual model has become a necessary tool for dailyimaging diagnosis. Imagine can directly and exactly provide diagnosticmessage, which also becomes important evidence and guidance. In recentyears, three dimensional emulational entity model is applied tocraniomaxillofacial surgery, spine surgery, cardiovascular surgery,interventional therapy, and such complicated fields. And also, it rendersits considerable superiority in the aspects of acquiring more detailedinformation of anatomia, of increasing the confidence and proficiencywhen doctors operate, of shortening the time of operation, etc. What isespecially worth concerning is that the three dimensional emulationalentity model has an irreplaceable role in some craniofacial abnormalities surgeries. When reviewing existing literature, it is hardly to find anyreport on the application of three dimensional emulational entity model insurgeries of children’s macrocephaly. Moreover, since the surgeries ofchildren’s macrocephaly have specifieness of reconstructing the craniumand skull base, and protecting head, the preparation of navigationalmodel and related application of operative navigation by pinpointing canhighly increase the rate of success and safety of surgeries.By means of comparing the respective application in cyber-virtualmodel and actual model, this research will define the fact that actualmodel technology has advantage of increasing precision and enhancingsecurity when operating surgeries of children’s macrocephaly, and quiteessential significance as well.【Objective】On the basis of computer simulation surgeries, by making entitymodel and practicing, measuring each related experimental parameters ofmodel and analysing respective results, this research aims at defining thefact that the computer emulational entity model technology has advantagein increasing the degree of satisfaction, shortening time and strengtheningsafety in the surgeries of children’s macrocephaly; and also, on this basis,making operative navigation model can increase related precision. Inshort words, this research aims at defining emulation entity model technology has availability and security in surgeries of children’smacrocephaly.【Methods】1. Collecting7series of clinical data of macrocephaly image, andmaking7emulational entity models of three dimensional technology incomputer, by rapid prototyping technology. And then separately copying5actual entity models according to1:1proportion in order to practiceoperations on them.2. Before practicing the operations, the virtual plan for surgeriesneeds to be completed in computer. Setting the models formed frompractices as a standard, recording each technical parameter fromcompleted virtual models and also setting them as reference standard. Atlast, setting acceptance criterion for completed entity models.3. Comparing each series of completion time of the first and the fifthentity models, which are completed and meets the acceptance criterion,on the rate of coincidence between them and the virtual models so thatthe degree of proficiency and satisfaction can be revealed.4. Using the final and best qualified model as a template, to makeoperative navigation model.5. Recording related parameters and calculating, to gain researchresults. 【Results】1. In the7series of objects, there are2series of models having theproblem that the first entity model has a failed result model after practice.They need to be operated again, planning the cyber-virtual surgery andmaking virtual models.2. After calculation, the average rates of error between sagittalbone bridge length and standard model length are,3.8%，3.3%，2.2%，3.0%，2.6%，2.8%，2.1%. In general, in these7series of models, theaverage length error rate of all first qualified final models is5.0%, andthe error rate of all fifth final models is1.2%. Such a distinctdifferentiation illustrates that, comparing with the first one, the error rateof final practice decreases while the degree of satisfaction increases.3. As to the results from operation time, the first qualified finalmodel from each series needs4.3h,3.3h,3.6h,2.7h,3.4h,3.0h,3.8h，separately. The fifth final model from each series needs2.7h,2.4h,2.5h,1.9h,3.0h,2.5h，2.5h, separately. The rates of saved time separately are37%，27%，31%，30%，12%，17%，34%; the differentiation is obvious.The degree of proficiency increases and the time is saved12%to37%.【Conclusions】1. The surgery of children’s macrocephaly has its complexity andspecifieness. The necessary anatomic information for surgeries can beacquired only from emulational entity models. So the surgery plan which comes from cyber-virtual model only might be incomplete and it is hardto complete surgery based on it. The plan needs modify and it is better tore-plan in computer to get emulational entity model which is more closeto the actual situation.2. By means of practicing repeatedly on entity models, improvingthe surgery method and perfect the surgery plan, doctors can reduce theerror in surgery so that the degree of satisfaction in surgery will increase.3. Making use of computer emotional entity models to practicerepeatedly, doctors can enhance their confidence and proficiency insurgery; can shorten the surgery time greatly; and also, can strengthen thesafety of surgery indirectly.4. The surgery of children’s macrocephaly has its specifieness ofreconstructing cranial cavity and protecting head, so the pinpoint insurgery is highly and seriously required. Acquiring the best surgery planfrom entity model practice and using operative navigation model from it,can increase the precision of surgery and enhance its safety. Thesignificance of applying operative navigation model to surgery ofchildren’s macrocephaly is mathematical.